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60 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Tobias Waldekranz
|
f7a70d650b |
net: bridge: switchdev: Ensure deferred event delivery on unoffload
When unoffloading a device, it is important to ensure that all
relevant deferred events are delivered to it before it disassociates
itself from the bridge.
Before this change, this was true for the normal case when a device
maps 1:1 to a net_bridge_port, i.e.
br0
/
swp0
When swp0 leaves br0, the call to switchdev_deferred_process() in
del_nbp() makes sure to process any outstanding events while the
device is still associated with the bridge.
In the case when the association is indirect though, i.e. when the
device is attached to the bridge via an intermediate device, like a
LAG...
br0
/
lag0
/
swp0
...then detaching swp0 from lag0 does not cause any net_bridge_port to
be deleted, so there was no guarantee that all events had been
processed before the device disassociated itself from the bridge.
Fix this by always synchronously processing all deferred events before
signaling completion of unoffloading back to the driver.
Fixes:
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|
Tobias Waldekranz
|
dc489f8625 |
net: bridge: switchdev: Skip MDB replays of deferred events on offload
Before this change, generation of the list of MDB events to replay
would race against the creation of new group memberships, either from
the IGMP/MLD snooping logic or from user configuration.
While new memberships are immediately visible to walkers of
br->mdb_list, the notification of their existence to switchdev event
subscribers is deferred until a later point in time. So if a replay
list was generated during a time that overlapped with such a window,
it would also contain a replay of the not-yet-delivered event.
The driver would thus receive two copies of what the bridge internally
considered to be one single event. On destruction of the bridge, only
a single membership deletion event was therefore sent. As a
consequence of this, drivers which reference count memberships (at
least DSA), would be left with orphan groups in their hardware
database when the bridge was destroyed.
This is only an issue when replaying additions. While deletion events
may still be pending on the deferred queue, they will already have
been removed from br->mdb_list, so no duplicates can be generated in
that scenario.
To a user this meant that old group memberships, from a bridge in
which a port was previously attached, could be reanimated (in
hardware) when the port joined a new bridge, without the new bridge's
knowledge.
For example, on an mv88e6xxx system, create a snooping bridge and
immediately add a port to it:
root@infix-06-0b-00:~$ ip link add dev br0 up type bridge mcast_snooping 1 && \
> ip link set dev x3 up master br0
And then destroy the bridge:
root@infix-06-0b-00:~$ ip link del dev br0
root@infix-06-0b-00:~$ mvls atu
ADDRESS FID STATE Q F 0 1 2 3 4 5 6 7 8 9 a
DEV:0 Marvell 88E6393X
33:33:00:00:00:6a 1 static - - 0 . . . . . . . . . .
33:33:ff:87:e4:3f 1 static - - 0 . . . . . . . . . .
ff:ff:ff:ff:ff:ff 1 static - - 0 1 2 3 4 5 6 7 8 9 a
root@infix-06-0b-00:~$
The two IPv6 groups remain in the hardware database because the
port (x3) is notified of the host's membership twice: once via the
original event and once via a replay. Since only a single delete
notification is sent, the count remains at 1 when the bridge is
destroyed.
Then add the same port (or another port belonging to the same hardware
domain) to a new bridge, this time with snooping disabled:
root@infix-06-0b-00:~$ ip link add dev br1 up type bridge mcast_snooping 0 && \
> ip link set dev x3 up master br1
All multicast, including the two IPv6 groups from br0, should now be
flooded, according to the policy of br1. But instead the old
memberships are still active in the hardware database, causing the
switch to only forward traffic to those groups towards the CPU (port
0).
Eliminate the race in two steps:
1. Grab the write-side lock of the MDB while generating the replay
list.
This prevents new memberships from showing up while we are generating
the replay list. But it leaves the scenario in which a deferred event
was already generated, but not delivered, before we grabbed the
lock. Therefore:
2. Make sure that no deferred version of a replay event is already
enqueued to the switchdev deferred queue, before adding it to the
replay list, when replaying additions.
Fixes:
|
||
Petr Machata
|
f2e2857b35 |
net: switchdev: Add a helper to replay objects on a bridge port
When a front panel joins a bridge via another netdevice (typically a LAG), the driver needs to learn about the objects configured on the bridge port. When the bridge port is offloaded by the driver for the first time, this can be achieved by passing a notifier to switchdev_bridge_port_offload(). The notifier is then invoked for the individual objects (such as VLANs) configured on the bridge, and can look for the interesting ones. Calling switchdev_bridge_port_offload() when the second port joins the bridge lower is unnecessary, but the replay is still needed. To that end, add a new function, switchdev_bridge_port_replay(), which does only the replay part of the _offload() function in exactly the same way as that function. Cc: Jiri Pirko <jiri@resnulli.us> Cc: Ivan Vecera <ivecera@redhat.com> Cc: Roopa Prabhu <roopa@nvidia.com> Cc: Nikolay Aleksandrov <razor@blackwall.org> Cc: bridge@lists.linux-foundation.org Signed-off-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Danielle Ratson <danieller@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
||
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Petr Machata
|
989280d6ea |
net: bridge: br_switchdev: Tolerate -EOPNOTSUPP when replaying MDB
There are two kinds of MDB entries to be replayed: port MDB entries, and host MDB entries. They are both replayed by br_switchdev_mdb_replay(). If the driver supports one kind, but lacks the other, the first -EOPNOTSUPP returned terminates the whole replay, including any further still-supported objects in the list. For this to cause issues, there must be MDB entries for both the host and the port being replayed. In that case, if the driver bails out from handling the host entry, the port entries are never replayed. However, the replay is currently only done when a switchdev port joins a bridge. There would be no port memberships at that point. Thus despite being erroneous, the code does not cause observable bugs. This is not an issue with other object kinds either, because there, each function replays one object kind. If a driver does not support that kind, it makes sense to bail out early. -EOPNOTSUPP is then ignored in nbp_switchdev_sync_objs(). For MDB, suppress the -EOPNOTSUPP error code in br_switchdev_mdb_replay() already, so that the whole list gets replayed. The reason we need this patch is that a future patch will introduce a replay that should be used when a front-panel port netdevice is enslaved to a bridge lower, in particular a LAG. The LAG netdevice can already have both host and port MDB entries. The port entries need to be replayed so that they are offloaded on the port that joins the LAG. Cc: Jiri Pirko <jiri@resnulli.us> Cc: Ivan Vecera <ivecera@redhat.com> Cc: Roopa Prabhu <roopa@nvidia.com> Cc: Nikolay Aleksandrov <razor@blackwall.org> Cc: bridge@lists.linux-foundation.org Signed-off-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Danielle Ratson <danieller@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
||
Vladimir Oltean
|
927cdea5d2 |
net: bridge: switchdev: don't notify FDB entries with "master dynamic"
There is a structural problem in switchdev, where the flag bits in
struct switchdev_notifier_fdb_info (added_by_user, is_local etc) only
represent a simplified / denatured view of what's in struct
net_bridge_fdb_entry :: flags (BR_FDB_ADDED_BY_USER, BR_FDB_LOCAL etc).
Each time we want to pass more information about struct
net_bridge_fdb_entry :: flags to struct switchdev_notifier_fdb_info
(here, BR_FDB_STATIC), we find that FDB entries were already notified to
switchdev with no regard to this flag, and thus, switchdev drivers had
no indication whether the notified entries were static or not.
For example, this command:
ip link add br0 type bridge && ip link set swp0 master br0
bridge fdb add dev swp0 00:01:02:03:04:05 master dynamic
has never worked as intended with switchdev. It causes a struct
net_bridge_fdb_entry to be passed to br_switchdev_fdb_notify() which has
a single flag set: BR_FDB_ADDED_BY_USER.
This is further passed to the switchdev notifier chain, where interested
drivers have no choice but to assume this is a static (does not age) and
sticky (does not migrate) FDB entry. So currently, all drivers offload
it to hardware as such, as can be seen below ("offload" is set).
bridge fdb get 00:01:02:03:04:05 dev swp0 master
00:01:02:03:04:05 dev swp0 offload master br0
The software FDB entry expires $ageing_time centiseconds after the
kernel last sees a packet with this MAC SA, and the bridge notifies its
deletion as well, so it eventually disappears from hardware too.
This is a problem, because it is actually desirable to start offloading
"master dynamic" FDB entries correctly - they should expire $ageing_time
centiseconds after the *hardware* port last sees a packet with this
MAC SA - and this is how the current incorrect behavior was discovered.
With an offloaded data plane, it can be expected that software only sees
exception path packets, so an otherwise active dynamic FDB entry would
be aged out by software sooner than it should.
With the change in place, these FDB entries are no longer offloaded:
bridge fdb get 00:01:02:03:04:05 dev swp0 master
00:01:02:03:04:05 dev swp0 master br0
and this also constitutes a better way (assuming a backport to stable
kernels) for user space to determine whether the kernel has the
capability of doing something sane with these or not.
As opposed to "master dynamic" FDB entries, on the current behavior of
which no one currently depends on (which can be deduced from the lack of
kselftests), Ido Schimmel explains that entries with the "extern_learn"
flag (BR_FDB_ADDED_BY_EXT_LEARN) should still be notified to switchdev,
since the spectrum driver listens to them (and this is kind of okay,
because although they are treated identically to "static", they are
expected to not age, and to roam).
Fixes:
|
||
Leon Romanovsky
|
028fb19c6b |
netlink: provide an ability to set default extack message
In netdev common pattern, extack pointer is forwarded to the drivers to be filled with error message. However, the caller can easily overwrite the filled message. Instead of adding multiple "if (!extack->_msg)" checks before any NL_SET_ERR_MSG() call, which appears after call to the driver, let's add new macro to common code. [1] https://lore.kernel.org/all/Y9Irgrgf3uxOjwUm@unreal Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Link: https://lore.kernel.org/r/6993fac557a40a1973dfa0095107c3d03d40bec1.1675171790.git.leon@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
Ido Schimmel
|
9c0ca02bac |
bridge: switchdev: Reflect MAB bridge port flag to device drivers
Reflect the 'BR_PORT_MAB' flag to device drivers so that: * Drivers that support MAB could act upon the flag being toggled. * Drivers that do not support MAB will prevent MAB from being enabled. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
Hans J. Schultz
|
27fabd02ab |
bridge: switchdev: Allow device drivers to install locked FDB entries
When the bridge is offloaded to hardware, FDB entries are learned and aged-out by the hardware. Some device drivers synchronize the hardware and software FDBs by generating switchdev events towards the bridge. When a port is locked, the hardware must not learn autonomously, as otherwise any host will blindly gain authorization. Instead, the hardware should generate events regarding hosts that are trying to gain authorization and their MAC addresses should be notified by the device driver as locked FDB entries towards the bridge driver. Allow device drivers to notify the bridge driver about such entries by extending the 'switchdev_notifier_fdb_info' structure with the 'locked' bit. The bit can only be set by device drivers and not by the bridge driver. Prevent a locked entry from being installed if MAB is not enabled on the bridge port. If an entry already exists in the bridge driver, reject the locked entry if the current entry does not have the "locked" flag set or if it points to a different port. The same semantics are implemented in the software data path. Signed-off-by: Hans J. Schultz <netdev@kapio-technology.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
Jakub Kicinski
|
0e55546b18 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/linux/netdevice.h net/core/dev.c |
||
Clément Léger
|
7f40ea2145 |
net: bridge: switchdev: check br_vlan_group() return value
br_vlan_group() can return NULL and thus return value must be checked
to avoid dereferencing a NULL pointer.
Fixes:
|
||
Arınç ÜNAL
|
c3976a3f84 |
net: bridge: offload BR_HAIRPIN_MODE, BR_ISOLATED, BR_MULTICAST_TO_UNICAST
Add BR_HAIRPIN_MODE, BR_ISOLATED and BR_MULTICAST_TO_UNICAST port flags to BR_PORT_FLAGS_HW_OFFLOAD so that switchdev drivers which have an offloaded data plane have a chance to reject these bridge port flags if they don't support them yet. It makes the code path go through the SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS driver handlers, which return -EINVAL for everything they don't recognize. For drivers that don't catch SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS at all, switchdev will return -EOPNOTSUPP for those which is then ignored, but those are in the minority. Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Link: https://lore.kernel.org/r/20220410134227.18810-1-arinc.unal@arinc9.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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|
Tobias Waldekranz
|
6284c723d9 |
net: bridge: mst: Notify switchdev drivers of VLAN MSTI migrations
Whenever a VLAN moves to a new MSTI, send a switchdev notification so that switchdevs can track a bridge's VID to MSTI mappings. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
Hans Schultz
|
fa1c833429 |
net: bridge: Add support for offloading of locked port flag
Various switchcores support setting ports in locked mode, so that clients behind locked ports cannot send traffic through the port unless a fdb entry is added with the clients MAC address. Signed-off-by: Hans Schultz <schultz.hans+netdev@gmail.com> Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
|
b28d580e29 |
net: bridge: switchdev: replay all VLAN groups
The major user of replayed switchdev objects is DSA, and so far it
hasn't needed information about anything other than bridge port VLANs,
so this is all that br_switchdev_vlan_replay() knows to handle.
DSA has managed to get by through replicating every VLAN addition on a
user port such that the same VLAN is also added on all DSA and CPU
ports, but there is a corner case where this does not work.
The mv88e6xxx DSA driver currently prints this error message as soon as
the first port of a switch joins a bridge:
mv88e6085 0x0000000008b96000:00: port 0 failed to add a6:ef:77:c8:5f:3d vid 1 to fdb: -95
where a6:ef:77:c8:5f:3d vid 1 is a local FDB entry corresponding to the
bridge MAC address in the default_pvid.
The -EOPNOTSUPP is returned by mv88e6xxx_port_db_load_purge() because it
tries to map VID 1 to a FID (the ATU is indexed by FID not VID), but
fails to do so. This is because ->port_fdb_add() is called before
->port_vlan_add() for VID 1.
The abridged timeline of the calls is:
br_add_if
-> netdev_master_upper_dev_link
-> dsa_port_bridge_join
-> switchdev_bridge_port_offload
-> br_switchdev_vlan_replay (*)
-> br_switchdev_fdb_replay
-> mv88e6xxx_port_fdb_add
-> nbp_vlan_init
-> nbp_vlan_add
-> mv88e6xxx_port_vlan_add
and the issue is that at the time of (*), the bridge port isn't in VID 1
(nbp_vlan_init hasn't been called), therefore br_switchdev_vlan_replay()
won't have anything to replay, therefore VID 1 won't be in the VTU by
the time mv88e6xxx_port_fdb_add() is called.
This happens only when the first port of a switch joins. For further
ports, the initial mv88e6xxx_port_vlan_add() is sufficient for VID 1 to
be loaded in the VTU (which is switch-wide, not per port).
The problem is somewhat unique to mv88e6xxx by chance, because most
other drivers offload an FDB entry by VID, so FDBs and VLANs can be
added asynchronously with respect to each other, but addressing the
issue at the bridge layer makes sense, since what mv88e6xxx requires
isn't absurd.
To fix this problem, we need to recognize that it isn't the VLAN group
of the port that we're interested in, but the VLAN group of the bridge
itself (so it isn't a timing issue, but rather insufficient information
being passed from switchdev to drivers).
As mentioned, currently nbp_switchdev_sync_objs() only calls
br_switchdev_vlan_replay() for VLANs corresponding to the port, but the
VLANs corresponding to the bridge itself, for local termination, also
need to be replayed. In this case, VID 1 is not (yet) present in the
port's VLAN group but is present in the bridge's VLAN group.
So to fix this bug, DSA is now obligated to explicitly handle VLANs
pointing towards the bridge in order to "close this race" (which isn't
really a race). As Tobias Waldekranz notices, this also implies that it
must explicitly handle port VLANs on foreign interfaces, something that
worked implicitly before:
https://patchwork.kernel.org/project/netdevbpf/patch/20220209213044.2353153-6-vladimir.oltean@nxp.com/#24735260
So in the end, br_switchdev_vlan_replay() must replay all VLANs from all
VLAN groups: all the ports, and the bridge itself.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Vladimir Oltean
|
263029ae31 |
net: bridge: make nbp_switchdev_unsync_objs() follow reverse order of sync()
There may be switchdev drivers that can add/remove a FDB or MDB entry only as long as the VLAN it's in has been notified and offloaded first. The nbp_switchdev_sync_objs() method satisfies this requirement on addition, but nbp_switchdev_unsync_objs() first deletes VLANs, then deletes MDBs and FDBs. Reverse the order of the function calls to cater to this requirement. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
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8d23a54f5b |
net: bridge: switchdev: differentiate new VLANs from changed ones
br_switchdev_port_vlan_add() currently emits a SWITCHDEV_PORT_OBJ_ADD event with a SWITCHDEV_OBJ_ID_PORT_VLAN for 2 distinct cases: - a struct net_bridge_vlan got created - an existing struct net_bridge_vlan was modified This makes it impossible for switchdev drivers to properly balance PORT_OBJ_ADD with PORT_OBJ_DEL events, so if we want to allow that to happen, we must provide a way for drivers to distinguish between a VLAN with changed flags and a new one. Annotate struct switchdev_obj_port_vlan with a "bool changed" that distinguishes the 2 cases above. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
|
326b212e9c |
net: bridge: switchdev: consistent function naming
Rename all recently imported functions in br_switchdev.c to start with a br_switchdev_* prefix. br_fdb_replay_one() -> br_switchdev_fdb_replay_one() br_fdb_replay() -> br_switchdev_fdb_replay() br_vlan_replay_one() -> br_switchdev_vlan_replay_one() br_vlan_replay() -> br_switchdev_vlan_replay() struct br_mdb_complete_info -> struct br_switchdev_mdb_complete_info br_mdb_complete() -> br_switchdev_mdb_complete() br_mdb_switchdev_host_port() -> br_switchdev_host_mdb_one() br_mdb_switchdev_host() -> br_switchdev_host_mdb() br_mdb_replay_one() -> br_switchdev_mdb_replay_one() br_mdb_replay() -> br_switchdev_mdb_replay() br_mdb_queue_one() -> br_switchdev_mdb_queue_one() Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Vladimir Oltean
|
9776457c78 |
net: bridge: mdb: move all switchdev logic to br_switchdev.c
The following functions: br_mdb_complete br_switchdev_mdb_populate br_mdb_replay_one br_mdb_queue_one br_mdb_replay br_mdb_switchdev_host_port br_mdb_switchdev_host br_switchdev_mdb_notify are only accessible from code paths where CONFIG_NET_SWITCHDEV is enabled. So move them to br_switchdev.c, in order for that code to be compiled out if that config option is disabled. Note that br_switchdev.c gets build regardless of whether CONFIG_BRIDGE_IGMP_SNOOPING is enabled or not, whereas br_mdb.c only got built when CONFIG_BRIDGE_IGMP_SNOOPING was enabled. So to preserve correct compilation with CONFIG_BRIDGE_IGMP_SNOOPING being disabled, we must now place an #ifdef around these functions in br_switchdev.c. The offending bridge data structures that need this are br->multicast_lock and br->mdb_list, these are also compiled out of struct net_bridge when CONFIG_BRIDGE_IGMP_SNOOPING is turned off. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Vladimir Oltean
|
4a6849e461 |
net: bridge: move br_vlan_replay to br_switchdev.c
br_vlan_replay() is relevant only if CONFIG_NET_SWITCHDEV is enabled, so move it to br_switchdev.c. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Vladimir Oltean
|
fab9eca884 |
net: bridge: create a common function for populating switchdev FDB entries
There are two places where a switchdev FDB entry is constructed, one is br_switchdev_fdb_notify() and the other is br_fdb_replay(). One uses a struct initializer, and the other declares the structure as uninitialized and populates the elements one by one. One problem when introducing new members of struct switchdev_notifier_fdb_info is that there is a risk for one of these functions to run with an uninitialized value. So centralize the logic of populating such structure into a dedicated function. Being the primary location where these structures are created, using an uninitialized variable and populating the members one by one should be fine, since this one function is supposed to assign values to all its members. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
|
5cda5272a4 |
net: bridge: move br_fdb_replay inside br_switchdev.c
br_fdb_replay is only called from switchdev code paths, so it makes sense to be disabled if switchdev is not enabled in the first place. As opposed to br_mdb_replay and br_vlan_replay which might be turned off depending on bridge support for multicast and VLANs, FDB support is always on. So moving br_mdb_replay and br_vlan_replay inside br_switchdev.c would mean adding some #ifdef's in br_switchdev.c, so we keep those where they are. The reason for the movement is that in future changes there will be some code reuse between br_switchdev_fdb_notify and br_fdb_replay. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
|
957e2235e5 |
net: make switchdev_bridge_port_{,unoffload} loosely coupled with the bridge
With the introduction of explicit offloading API in switchdev in commit |
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Vladimir Oltean
|
2e19bb35ce |
net: bridge: switchdev: fix incorrect use of FDB flags when picking the dst device
Nikolay points out that it is incorrect to assume that it is impossible
to have an fdb entry with fdb->dst == NULL and the BR_FDB_LOCAL bit in
fdb->flags not set. This is because there are reader-side places that
test_bit(BR_FDB_LOCAL, &fdb->flags) without the br->hash_lock, and if
the updating of the FDB entry happens on another CPU, there are no
memory barriers at writer or reader side which would ensure that the
reader sees the updates to both fdb->flags and fdb->dst in the same
order, i.e. the reader will not see an inconsistent FDB entry.
So we must be prepared to deal with FDB entries where fdb->dst and
fdb->flags are in a potentially inconsistent state, and that means that
fdb->dst == NULL should remain a condition to pick the net_device that
we report to switchdev as being the bridge device, which is what the
code did prior to the blamed patch.
Fixes:
|
||
|
Vladimir Oltean
|
52e4bec155 |
net: bridge: switchdev: treat local FDBs the same as entries towards the bridge
Currently the following script: 1. ip link add br0 type bridge vlan_filtering 1 && ip link set br0 up 2. ip link set swp2 up && ip link set swp2 master br0 3. ip link set swp3 up && ip link set swp3 master br0 4. ip link set swp4 up && ip link set swp4 master br0 5. bridge vlan del dev swp2 vid 1 6. bridge vlan del dev swp3 vid 1 7. ip link set swp4 nomaster 8. ip link set swp3 nomaster produces the following output: [ 641.010738] sja1105 spi0.1: port 2 failed to delete 00:1f:7b:63:02:48 vid 1 from fdb: -2 [ swp2, swp3 and br0 all have the same MAC address, the one listed above ] In short, this happens because the number of FDB entry additions notified to switchdev is unbalanced with the number of deletions. At step 1, the bridge has a random MAC address. At step 2, the br_fdb_replay of swp2 receives this initial MAC address. Then the bridge inherits the MAC address of swp2 via br_fdb_change_mac_address(), and it notifies switchdev (only swp2 at this point) of the deletion of the random MAC address and the addition of 00:1f:7b:63:02:48 as a local FDB entry with fdb->dst == swp2, in VLANs 0 and the default_pvid (1). During step 7: del_nbp -> br_fdb_delete_by_port(br, p, vid=0, do_all=1); -> fdb_delete_local(br, p, f); br_fdb_delete_by_port() deletes all entries towards the ports, regardless of vid, because do_all is 1. fdb_delete_local() has logic to migrate local FDB entries deleted from one port to another port which shares the same MAC address and is in the same VLAN, or to the bridge device itself. This migration happens without notifying switchdev of the deletion on the old port and the addition on the new one, just fdb->dst is changed and the added_by_user flag is cleared. In the example above, the del_nbp(swp4) causes the "addr 00:1f:7b:63:02:48 vid 1" local FDB entry with fdb->dst == swp4 that existed up until then to be migrated directly towards the bridge (fdb->dst == NULL). This is because it cannot be migrated to any of the other ports (swp2 and swp3 are not in VLAN 1). After the migration to br0 takes place, swp4 requests a deletion replay of all FDB entries. Since the "addr 00:1f:7b:63:02:48 vid 1" entry now point towards the bridge, a deletion of it is replayed. There was just a prior addition of this address, so the switchdev driver deletes this entry. Then, the del_nbp(swp3) at step 8 triggers another br_fdb_replay, and switchdev is notified again to delete "addr 00:1f:7b:63:02:48 vid 1". But it can't because it no longer has it, so it returns -ENOENT. There are other possibilities to trigger this issue, but this is by far the simplest to explain. To fix this, we must avoid the situation where the addition of an FDB entry is notified to switchdev as a local entry on a port, and the deletion is notified on the bridge itself. Considering that the 2 types of FDB entries are completely equivalent and we cannot have the same MAC address as a local entry on 2 bridge ports, or on a bridge port and pointing towards the bridge at the same time, it makes sense to hide away from switchdev completely the fact that a local FDB entry is associated with a given bridge port at all. Just say that it points towards the bridge, it should make no difference whatsoever to the switchdev driver and should even lead to a simpler overall implementation, will less cases to handle. This also avoids any modification at all to the core bridge driver, just what is reported to switchdev changes. With the local/permanent entries on bridge ports being already reported to user space, it is hard to believe that the bridge behavior can change in any backwards-incompatible way such as making all local FDB entries point towards the bridge. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
||
|
Vladimir Oltean
|
b4454bc6a0 |
net: bridge: switchdev: replay the entire FDB for each port
Currently when a switchdev port joins a bridge, we replay all FDB
entries pointing towards that port or towards the bridge.
However, this is insufficient in certain situations:
(a) DSA, through its assisted_learning_on_cpu_port logic, snoops
dynamically learned FDB entries on foreign interfaces.
These are FDB entries that are pointing neither towards the newly
joined switchdev port, nor towards the bridge. So these addresses
would be missed when joining a bridge where a foreign interface has
already learned some addresses, and they would also linger on if the
DSA port leaves the bridge before the foreign interface forgets them.
None of this happens if we replay the entire FDB when the port joins.
(b) There is a desire to treat local FDB entries on a port (i.e. the
port's termination MAC address) identically to FDB entries pointing
towards the bridge itself. More details on the reason behind this in
the next patch. The point is that this cannot be done given the
current structure of br_fdb_replay() in this situation:
ip link set swp0 master br0 # br0 inherits its MAC address from swp0
ip link set swp1 master br0
What is desirable is that when swp1 joins the bridge, br_fdb_replay()
also notifies swp1 of br0's MAC address, but this won't in fact
happen because the MAC address of br0 does not have fdb->dst == NULL
(it doesn't point towards the bridge), but it has fdb->dst == swp0.
So our current logic makes it impossible for that address to be
replayed. But if we dump the entire FDB instead of just the entries
with fdb->dst == swp1 and fdb->dst == NULL, then the inherited MAC
address of br0 will be replayed too, which is what we need.
A natural question arises: say there is an FDB entry to be replayed,
like a MAC address dynamically learned on a foreign interface that
belongs to a bridge where no switchdev port has joined yet. If 10
switchdev ports belonging to the same driver join this bridge, one by
one, won't every port get notified 10 times of the foreign FDB entry,
amounting to a total of 100 notifications for this FDB entry in the
switchdev driver?
Well, yes, but this is where the "void *ctx" argument for br_fdb_replay
is useful: every port of the switchdev driver is notified whenever any
other port requests an FDB replay, but because the replay was initiated
by a different port, its context is different from the initiating port's
context, so it ignores those replays.
So the foreign FDB entry will be installed only 10 times, once per port.
This is done so that the following 4 code paths are always well balanced:
(a) addition of foreign FDB entry is replayed when port joins bridge
(b) deletion of foreign FDB entry is replayed when port leaves bridge
(c) addition of foreign FDB entry is notified to all ports currently in bridge
(c) deletion of foreign FDB entry is notified to all ports currently in bridge
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
||
|
Vladimir Oltean
|
c538115439 |
net: bridge: fix build when setting skb->offload_fwd_mark with CONFIG_NET_SWITCHDEV=n
Switchdev support can be disabled at compile time, and in that case,
struct sk_buff will not contain the offload_fwd_mark field.
To make the code in br_forward.c work in both cases, we do what is done
in other places and we create a helper function, with an empty shim
definition, that is implemented by the br_switchdev.o translation module.
This is always compiled if and only if CONFIG_NET_SWITCHDEV is y or m.
Reported-by: kernel test robot <lkp@intel.com>
Fixes:
|
||
|
Tobias Waldekranz
|
472111920f |
net: bridge: switchdev: allow the TX data plane forwarding to be offloaded
Allow switchdevs to forward frames from the CPU in accordance with the bridge configuration in the same way as is done between bridge ports. This means that the bridge will only send a single skb towards one of the ports under the switchdev's control, and expects the driver to deliver the packet to all eligible ports in its domain. Primarily this improves the performance of multicast flows with multiple subscribers, as it allows the hardware to perform the frame replication. The basic flow between the driver and the bridge is as follows: - When joining a bridge port, the switchdev driver calls switchdev_bridge_port_offload() with tx_fwd_offload = true. - The bridge sends offloadable skbs to one of the ports under the switchdev's control using skb->offload_fwd_mark = true. - The switchdev driver checks the skb->offload_fwd_mark field and lets its FDB lookup select the destination port mask for this packet. v1->v2: - convert br_input_skb_cb::fwd_hwdoms to a plain unsigned long - introduce a static key "br_switchdev_fwd_offload_used" to minimize the impact of the newly introduced feature on all the setups which don't have hardware that can make use of it - introduce a check for nbp->flags & BR_FWD_OFFLOAD to optimize cache line access - reorder nbp_switchdev_frame_mark_accel() and br_handle_vlan() in __br_forward() - do not strip VLAN on egress if forwarding offload on VLAN-aware bridge is being used - propagate errors from .ndo_dfwd_add_station() if not EOPNOTSUPP v2->v3: - replace the solution based on .ndo_dfwd_add_station with a solution based on switchdev_bridge_port_offload - rename BR_FWD_OFFLOAD to BR_TX_FWD_OFFLOAD v3->v4: rebase v4->v5: - make sure the static key is decremented on bridge port unoffload - more function and variable renaming and comments for them: br_switchdev_fwd_offload_used to br_switchdev_tx_fwd_offload br_switchdev_accels_skb to br_switchdev_frame_uses_tx_fwd_offload nbp_switchdev_frame_mark_tx_fwd to nbp_switchdev_frame_mark_tx_fwd_to_hwdom nbp_switchdev_frame_mark_accel to nbp_switchdev_frame_mark_tx_fwd_offload fwd_accel to tx_fwd_offload Signed-off-by: Tobias Waldekranz <tobias@waldekranz.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> |
||
|
Vladimir Oltean
|
4e51bf44a0 |
net: bridge: move the switchdev object replay helpers to "push" mode
Starting with commit |
||
|
Vladimir Oltean
|
2f5dc00f7a |
net: bridge: switchdev: let drivers inform which bridge ports are offloaded
On reception of an skb, the bridge checks if it was marked as 'already
forwarded in hardware' (checks if skb->offload_fwd_mark == 1), and if it
is, it assigns the source hardware domain of that skb based on the
hardware domain of the ingress port. Then during forwarding, it enforces
that the egress port must have a different hardware domain than the
ingress one (this is done in nbp_switchdev_allowed_egress).
Non-switchdev drivers don't report any physical switch id (neither
through devlink nor .ndo_get_port_parent_id), therefore the bridge
assigns them a hardware domain of 0, and packets coming from them will
always have skb->offload_fwd_mark = 0. So there aren't any restrictions.
Problems appear due to the fact that DSA would like to perform software
fallback for bonding and team interfaces that the physical switch cannot
offload.
+-- br0 ---+
/ / | \
/ / | \
/ | | bond0
/ | | / \
swp0 swp1 swp2 swp3 swp4
There, it is desirable that the presence of swp3 and swp4 under a
non-offloaded LAG does not preclude us from doing hardware bridging
beteen swp0, swp1 and swp2. The bandwidth of the CPU is often times high
enough that software bridging between {swp0,swp1,swp2} and bond0 is not
impractical.
But this creates an impossible paradox given the current way in which
port hardware domains are assigned. When the driver receives a packet
from swp0 (say, due to flooding), it must set skb->offload_fwd_mark to
something.
- If we set it to 0, then the bridge will forward it towards swp1, swp2
and bond0. But the switch has already forwarded it towards swp1 and
swp2 (not to bond0, remember, that isn't offloaded, so as far as the
switch is concerned, ports swp3 and swp4 are not looking up the FDB,
and the entire bond0 is a destination that is strictly behind the
CPU). But we don't want duplicated traffic towards swp1 and swp2, so
it's not ok to set skb->offload_fwd_mark = 0.
- If we set it to 1, then the bridge will not forward the skb towards
the ports with the same switchdev mark, i.e. not to swp1, swp2 and
bond0. Towards swp1 and swp2 that's ok, but towards bond0? It should
have forwarded the skb there.
So the real issue is that bond0 will be assigned the same hardware
domain as {swp0,swp1,swp2}, because the function that assigns hardware
domains to bridge ports, nbp_switchdev_add(), recurses through bond0's
lower interfaces until it finds something that implements devlink (calls
dev_get_port_parent_id with bool recurse = true). This is a problem
because the fact that bond0 can be offloaded by swp3 and swp4 in our
example is merely an assumption.
A solution is to give the bridge explicit hints as to what hardware
domain it should use for each port.
Currently, the bridging offload is very 'silent': a driver registers a
netdevice notifier, which is put on the netns's notifier chain, and
which sniffs around for NETDEV_CHANGEUPPER events where the upper is a
bridge, and the lower is an interface it knows about (one registered by
this driver, normally). Then, from within that notifier, it does a bunch
of stuff behind the bridge's back, without the bridge necessarily
knowing that there's somebody offloading that port. It looks like this:
ip link set swp0 master br0
|
v
br_add_if() calls netdev_master_upper_dev_link()
|
v
call_netdevice_notifiers
|
v
dsa_slave_netdevice_event
|
v
oh, hey! it's for me!
|
v
.port_bridge_join
What we do to solve the conundrum is to be less silent, and change the
switchdev drivers to present themselves to the bridge. Something like this:
ip link set swp0 master br0
|
v
br_add_if() calls netdev_master_upper_dev_link()
|
v bridge: Aye! I'll use this
call_netdevice_notifiers ^ ppid as the
| | hardware domain for
v | this port, and zero
dsa_slave_netdevice_event | if I got nothing.
| |
v |
oh, hey! it's for me! |
| |
v |
.port_bridge_join |
| |
+------------------------+
switchdev_bridge_port_offload(swp0, swp0)
Then stacked interfaces (like bond0 on top of swp3/swp4) would be
treated differently in DSA, depending on whether we can or cannot
offload them.
The offload case:
ip link set bond0 master br0
|
v
br_add_if() calls netdev_master_upper_dev_link()
|
v bridge: Aye! I'll use this
call_netdevice_notifiers ^ ppid as the
| | switchdev mark for
v | bond0.
dsa_slave_netdevice_event | Coincidentally (or not),
| | bond0 and swp0, swp1, swp2
v | all have the same switchdev
hmm, it's not quite for me, | mark now, since the ASIC
but my driver has already | is able to forward towards
called .port_lag_join | all these ports in hw.
for it, because I have |
a port with dp->lag_dev == bond0. |
| |
v |
.port_bridge_join |
for swp3 and swp4 |
| |
+------------------------+
switchdev_bridge_port_offload(bond0, swp3)
switchdev_bridge_port_offload(bond0, swp4)
And the non-offload case:
ip link set bond0 master br0
|
v
br_add_if() calls netdev_master_upper_dev_link()
|
v bridge waiting:
call_netdevice_notifiers ^ huh, switchdev_bridge_port_offload
| | wasn't called, okay, I'll use a
v | hwdom of zero for this one.
dsa_slave_netdevice_event : Then packets received on swp0 will
| : not be software-forwarded towards
v : swp1, but they will towards bond0.
it's not for me, but
bond0 is an upper of swp3
and swp4, but their dp->lag_dev
is NULL because they couldn't
offload it.
Basically we can draw the conclusion that the lowers of a bridge port
can come and go, so depending on the configuration of lowers for a
bridge port, it can dynamically toggle between offloaded and unoffloaded.
Therefore, we need an equivalent switchdev_bridge_port_unoffload too.
This patch changes the way any switchdev driver interacts with the
bridge. From now on, everybody needs to call switchdev_bridge_port_offload
and switchdev_bridge_port_unoffload, otherwise the bridge will treat the
port as non-offloaded and allow software flooding to other ports from
the same ASIC.
Note that these functions lay the ground for a more complex handshake
between switchdev drivers and the bridge in the future.
For drivers that will request a replay of the switchdev objects when
they offload and unoffload a bridge port (DSA, dpaa2-switch, ocelot), we
place the call to switchdev_bridge_port_unoffload() strategically inside
the NETDEV_PRECHANGEUPPER notifier's code path, and not inside
NETDEV_CHANGEUPPER. This is because the switchdev object replay helpers
need the netdev adjacency lists to be valid, and that is only true in
NETDEV_PRECHANGEUPPER.
Cc: Vadym Kochan <vkochan@marvell.com>
Cc: Taras Chornyi <tchornyi@marvell.com>
Cc: Ioana Ciornei <ioana.ciornei@nxp.com>
Cc: Lars Povlsen <lars.povlsen@microchip.com>
Cc: Steen Hegelund <Steen.Hegelund@microchip.com>
Cc: UNGLinuxDriver@microchip.com
Cc: Claudiu Manoil <claudiu.manoil@nxp.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch: regression
Acked-by: Ioana Ciornei <ioana.ciornei@nxp.com> # dpaa2-switch
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com> # ocelot-switch
Signed-off-by: David S. Miller <davem@davemloft.net>
|
||
|
Tobias Waldekranz
|
8582661048 |
net: bridge: switchdev: recycle unused hwdoms
Since hwdoms have only been used thus far for equality comparisons, the
bridge has used the simplest possible assignment policy; using a
counter to keep track of the last value handed out.
With the upcoming transmit offloading, we need to perform set
operations efficiently based on hwdoms, e.g. we want to answer
questions like "has this skb been forwarded to any port within this
hwdom?"
Move to a bitmap-based allocation scheme that recycles hwdoms once all
members leaves the bridge. This means that we can use a single
unsigned long to keep track of the hwdoms that have received an skb.
v1->v2: convert the typedef DECLARE_BITMAP(br_hwdom_map_t, BR_HWDOM_MAX)
into a plain unsigned long.
v2->v6: none
Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
||
|
Tobias Waldekranz
|
f7cf972f93 |
net: bridge: disambiguate offload_fwd_mark
Before this change, four related - but distinct - concepts where named
offload_fwd_mark:
- skb->offload_fwd_mark: Set by the switchdev driver if the underlying
hardware has already forwarded this frame to the other ports in the
same hardware domain.
- nbp->offload_fwd_mark: An idetifier used to group ports that share
the same hardware forwarding domain.
- br->offload_fwd_mark: Counter used to make sure that unique IDs are
used in cases where a bridge contains ports from multiple hardware
domains.
- skb->cb->offload_fwd_mark: The hardware domain on which the frame
ingressed and was forwarded.
Introduce the term "hardware forwarding domain" ("hwdom") in the
bridge to denote a set of ports with the following property:
If an skb with skb->offload_fwd_mark set, is received on a port
belonging to hwdom N, that frame has already been forwarded to all
other ports in hwdom N.
By decoupling the name from "offload_fwd_mark", we can extend the
term's definition in the future - e.g. to add constraints that
describe expected egress behavior - without overloading the meaning of
"offload_fwd_mark".
- nbp->offload_fwd_mark thus becomes nbp->hwdom.
- br->offload_fwd_mark becomes br->last_hwdom.
- skb->cb->offload_fwd_mark becomes skb->cb->src_hwdom. The slight
change in naming here mandates a slight change in behavior of the
nbp_switchdev_frame_mark() function. Previously, it only set this
value in skb->cb for packets with skb->offload_fwd_mark true (ones
which were forwarded in hardware). Whereas now we always track the
incoming hwdom for all packets coming from a switchdev (even for the
packets which weren't forwarded in hardware, such as STP BPDUs, IGMP
reports etc). As all uses of skb->cb->offload_fwd_mark were already
gated behind checks of skb->offload_fwd_mark, this will not introduce
any functional change, but it paves the way for future changes where
the ingressing hwdom must be known for frames coming from a switchdev
regardless of whether they were forwarded in hardware or not
(basically, if the skb comes from a switchdev, skb->cb->src_hwdom now
always tracks which one).
A typical example where this is relevant: the switchdev has a fixed
configuration to trap STP BPDUs, but STP is not running on the bridge
and the group_fwd_mask allows them to be forwarded. Say we have this
setup:
br0
/ | \
/ | \
swp0 swp1 swp2
A BPDU comes in on swp0 and is trapped to the CPU; the driver does not
set skb->offload_fwd_mark. The bridge determines that the frame should
be forwarded to swp{1,2}. It is imperative that forward offloading is
_not_ allowed in this case, as the source hwdom is already "poisoned".
Recording the source hwdom allows this case to be handled properly.
v2->v3: added code comments
v3->v6: none
Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
||
|
Tobias Waldekranz
|
6eb38bf8eb |
net: bridge: switchdev: send FDB notifications for host addresses
Treat addresses added to the bridge itself in the same way as regular ports and send out a notification so that drivers may sync it down to the hardware FDB. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
||
|
Vladimir Oltean
|
3e19ae7c6f |
net: bridge: use READ_ONCE() and WRITE_ONCE() compiler barriers for fdb->dst
Annotate the writer side of fdb->dst: - fdb_create() - br_fdb_update() - fdb_add_entry() - br_fdb_external_learn_add() with WRITE_ONCE() and the reader side: - br_fdb_test_addr() - br_fdb_update() - fdb_fill_info() - fdb_add_entry() - fdb_delete_by_addr_and_port() - br_fdb_external_learn_add() - br_switchdev_fdb_notify() with compiler barriers such that the readers do not attempt to reload fdb->dst multiple times, leading to potentially different destination ports when the fdb entry is updated concurrently. This is especially important in read-side sections where fdb->dst is used more than once, but let's convert all accesses for the sake of uniformity. Suggested-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
||
|
Vladimir Oltean
|
2c4eca3ef7 |
net: bridge: switchdev: include local flag in FDB notifications
As explained in bugfix commit
|
||
|
Tobias Waldekranz
|
e5b4b8988b |
net: bridge: switchdev: refactor br_switchdev_fdb_notify
Instead of having to add more and more arguments to br_switchdev_fdb_call_notifiers, get rid of it and build the info struct directly in br_switchdev_fdb_notify. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
||
|
Vladimir Oltean
|
6ab4c3117a |
net: bridge: don't notify switchdev for local FDB addresses
As explained in this discussion:
https://lore.kernel.org/netdev/20210117193009.io3nungdwuzmo5f7@skbuf/
the switchdev notifiers for FDB entries managed to have a zero-day bug.
The bridge would not say that this entry is local:
ip link add br0 type bridge
ip link set swp0 master br0
bridge fdb add dev swp0 00:01:02:03:04:05 master local
and the switchdev driver would be more than happy to offload it as a
normal static FDB entry. This is despite the fact that 'local' and
non-'local' entries have completely opposite directions: a local entry
is locally terminated and not forwarded, whereas a static entry is
forwarded and not locally terminated. So, for example, DSA would install
this entry on swp0 instead of installing it on the CPU port as it should.
There is an even sadder part, which is that the 'local' flag is implicit
if 'static' is not specified, meaning that this command produces the
same result of adding a 'local' entry:
bridge fdb add dev swp0 00:01:02:03:04:05 master
I've updated the man pages for 'bridge', and after reading it now, it
should be pretty clear to any user that the commands above were broken
and should have never resulted in the 00:01:02:03:04:05 address being
forwarded (this behavior is coherent with non-switchdev interfaces):
https://patchwork.kernel.org/project/netdevbpf/cover/20210211104502.2081443-1-olteanv@gmail.com/
If you're a user reading this and this is what you want, just use:
bridge fdb add dev swp0 00:01:02:03:04:05 master static
Because switchdev should have given drivers the means from day one to
classify FDB entries as local/non-local, but didn't, it means that all
drivers are currently broken. So we can just as well omit the switchdev
notifications for local FDB entries, which is exactly what this patch
does to close the bug in stable trees. For further development work
where drivers might want to trap the local FDB entries to the host, we
can add a 'bool is_local' to br_switchdev_fdb_call_notifiers(), and
selectively make drivers act upon that bit, while all the others ignore
those entries if the 'is_local' bit is set.
Fixes:
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Vladimir Oltean
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dcbdf1350e |
net: bridge: propagate extack through switchdev_port_attr_set
The benefit is the ability to propagate errors from switchdev drivers for the SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING and SWITCHDEV_ATTR_ID_BRIDGE_VLAN_PROTOCOL attributes. 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> |
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Vladimir Oltean
|
e18f4c18ab |
net: switchdev: pass flags and mask to both {PRE_,}BRIDGE_FLAGS attributes
This switchdev attribute offers a counterproductive API for a driver writer, because although br_switchdev_set_port_flag gets passed a "flags" and a "mask", those are passed piecemeal to the driver, so while the PRE_BRIDGE_FLAGS listener knows what changed because it has the "mask", the BRIDGE_FLAGS listener doesn't, because it only has the final value. But certain drivers can offload only certain combinations of settings, like for example they cannot change unicast flooding independently of multicast flooding - they must be both on or both off. The way the information is passed to switchdev makes drivers not expressive enough, and unable to reject this request ahead of time, in the PRE_BRIDGE_FLAGS notifier, so they are forced to reject it during the deferred BRIDGE_FLAGS attribute, where the rejection is currently ignored. This patch also changes drivers to make use of the "mask" field for edge detection when possible. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
|
078bbb851e |
net: bridge: don't print in br_switchdev_set_port_flag
For the netlink interface, propagate errors through extack rather than simply printing them to the console. For the sysfs interface, we still print to the console, but at least that's one layer higher than in switchdev, which also allows us to silently ignore the offloading of flags if that is ever needed in the future. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
|
304ae3bf1c |
net: bridge: offload all port flags at once in br_setport
If for example this command: ip link set swp0 type bridge_slave flood off mcast_flood off learning off succeeded at configuring BR_FLOOD and BR_MCAST_FLOOD but not at BR_LEARNING, there would be no attempt to revert the partial state in any way. Arguably, if the user changes more than one flag through the same netlink command, this one _should_ be all or nothing, which means it should be passed through switchdev as all or nothing. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Vladimir Oltean
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b7a9e0da2d |
net: switchdev: remove vid_begin -> vid_end range from VLAN objects
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
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Nikolay Aleksandrov
|
d38c6e3db0 |
net: bridge: fdb: convert offloaded to use bitops
Convert the offloaded field to a flag and use bitops. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Nikolay Aleksandrov
|
ac3ca6af44 |
net: bridge: fdb: convert added_by_user to bitops
Straight-forward convert of the added_by_user field to bitops. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Florian Fainelli
|
d45224d604 |
net: switchdev: Replace port attr set SDO with a notification
Drop switchdev_ops.switchdev_port_attr_set. Drop the uses of this field from all clients, which were migrated to use switchdev notification in the previous patches. Add a new function switchdev_port_attr_notify() that sends the switchdev notifications SWITCHDEV_PORT_ATTR_SET and calls the blocking (process) notifier chain. We have one odd case within net/bridge/br_switchdev.c with the SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS attribute identifier that requires executing from atomic context, we deal with that one specifically. Drop __switchdev_port_attr_set() and update switchdev_port_attr_set() likewise. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Florian Fainelli
|
1ef0764486 |
net: bridge: Stop calling switchdev_port_attr_get()
Now that all switchdev drivers have been converted to check the SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS flags and report flags that they do not support accordingly, we can migrate the bridge code to try to set that attribute first, check the results and then do the actual setting. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Florian Fainelli
|
bccb30254a |
net: Get rid of SWITCHDEV_ATTR_ID_PORT_PARENT_ID
Now that we have a dedicated NDO for getting a port's parent ID, get rid of SWITCHDEV_ATTR_ID_PORT_PARENT_ID and convert all callers to use the NDO exclusively. This is a preliminary change to getting rid of switchdev_ops eventually. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Florian Fainelli
|
d6abc59694 |
net: Introduce ndo_get_port_parent_id()
In preparation for getting rid of switchdev_ops, create a dedicated NDO operation for getting the port's parent identifier. There are essentially two classes of drivers that need to implement getting the port's parent ID which are VF/PF drivers with a built-in switch, and pure switchdev drivers such as mlxsw, ocelot, dsa etc. We introduce a helper function: dev_get_port_parent_id() which supports recursion into the lower devices to obtain the first port's parent ID. Convert the bridge, core and ipv4 multicast routing code to check for such ndo_get_port_parent_id() and call the helper function when valid before falling back to switchdev_port_attr_get(). This will allow us to convert all relevant drivers in one go instead of having to implement both switchdev_port_attr_get() and ndo_get_port_parent_id() operations, then get rid of switchdev_port_attr_get(). Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Petr Machata
|
6685987c29 |
switchdev: Add extack argument to call_switchdev_notifiers()
A follow-up patch will enable vetoing of FDB entries. Make it possible to communicate details of why an FDB entry is not acceptable back to the user. Signed-off-by: Petr Machata <petrm@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Petr Machata
|
69b7320e14 |
net: switchdev: Add extack argument to switchdev_port_obj_add()
After the previous patch, bridge driver has extack argument available to pass to switchdev. Therefore extend switchdev_port_obj_add() with this argument, updating all callers, and passing the argument through to switchdev_port_obj_notify(). Signed-off-by: Petr Machata <petrm@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Ivan Vecera <ivecera@redhat.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Petr Machata
|
169327d585 |
net: bridge: Propagate extack to switchdev
ndo_bridge_setlink has been updated in the previous patch to have extack available, and changelink RTNL op has had this argument since the time extack was added. Propagate both through the bridge driver to eventually reach br_switchdev_port_vlan_add(), where it will be used by subsequent patches. Signed-off-by: Petr Machata <petrm@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Acked-by: Ivan Vecera <ivecera@redhat.com> Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> |