The inetaddr notification block is currently implemented in the main
driver file, but this isn't really appropriate, as it mainly creates and
destroys router interfaces (RIFs) which belong with the rest of the
router code.

This will become even more apparent later on when we'll need to bind
these RIFs to virtual routers according to the VRF's table.

Structure the driver better and prevent unnecessary function exports by
moving the RIF related code with the rest of the router code.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow 'unreachable', 'blackhole' and 'prohibit' route types to be
programmed into the device by sending any packet hitting them to the
CPU.

This is needed so that users will be able to program a default route
into the VRF's table, thereby preventing lookup from leaking to other
tables.

Audit the code paths to make sure we don't rely on the presence of a
nexthop netdev, as it doesn't exist for above mentioned route types.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the structure of the LPM tree changes (f.e., due to the addition of
a new prefix), we unbind the old tree and then bind the new one. This
may result in temporary packet loss.

Instead, overwrite the old binding with the new one.

Fixes: 6b75c480 ("mlxsw: spectrum_router: Add virtual router management")
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Upon the reception of an ENTRY_REPLACE notification, resolve the FIB
node corresponding to the prefix and length and insert the new route
before the first matching entry.

Since the notification also signals the deletion of the replaced route,
delete it from the driver's cache.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a new route is appended, it's placed after existing routes sharing
the same parameters (prefix, length, table ID, TOS and priority).

While the device supports only one route with the same prefix and length
in a single table, it's important to correctly place the appended route
in the driver's cache, as when a route is deleted the next one is
programmed into the device.

Following the reception of an ENTRY_APPEND notification, resolve the
FIB node corresponding to the prefix and length and correctly place the
new entry in its entry list.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the device, routes are indexed in a routing table based on the prefix
and its length. This is in contrast to the kernel's FIB where several
FIB aliases can exist with these parameters being identical. In such
cases, the routes will be sorted by table ID (LOCAL first, then MAIN),
TOS and finally priority (metric).

During lookup, these routes will be evaluated in order. In case the
packet's TOS field is non-zero and a FIB alias with a matching TOS is
found, then it's selected. Otherwise, the lookup defaults to the route
with TOS 0 (if it exists). However, if the requested scope is narrower
than the one found, then the lookup continues.

To best reflect the kernel's datapath we should take the above into
account. Given a prefix and its length, the reflected route will always
be the first one in the FIB alias list. However, if the route has a
non-zero TOS then its action will be converted to trap instead of
forward, since we currently don't support TOS-based routing. If this
turns out to be a real issue, we can add support for that using
policy-based switching.

The route's scope can be effectively ignored as any packet being routed
by the device would've been looked-up using the widest scope (UNIVERSE).

To achieve that we need to do two changes. Firstly, we need to create
another struct (FIB node) that will hold the list of FIB entries sharing
the same prefix and length. This struct will be hashed using these two
parameters.

Secondly, we need to change the route reflection to match the above
logic, so that the first FIB entry in the list will be programmed into
the device while the rest will remain in the driver's cache in case of
subsequent changes.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The kernel resolves the nexthops for a given route using
FIB_LOOKUP_IGNORE_LINKSTATE which means a notification can be sent for a
route with one of its nexthops being LINKDOWN.

In case IGNORE_ROUTES_WITH_LINKDOWN is set for the nexthop netdev, then
we shouldn't reflect the nexthop to the device's table.

Once the nexthop netdev's carrier goes up we'll be notified using NH_ADD
and reflect it to the device.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the last IP address is removed from a netdev, its RIF is deleted.
However, if user didn't first remove neighbours and nexthops using this
interface, then they would still be present in the device's tables.

Therefore, whenever a RIF is deleted, make sure all the neighbours and
nexthops (adjacency entries) using it are removed from the relevant
tables as well.

The action associated with any route using this RIF would be refreshed,
most likely to trap. If the kernel decides to remove the route (f.e.,
because all the nexthops are now DEAD), then an event would be sent,
causing the route to be removed from the device.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a packet hits a multipath route in the device's routing table, a
hash is computed over its headers, which is then used to select the
appropriate nexthop from the device's adjacency table.

There are situations in which the kernel removes a nexthop from a
multipath route (e.g., no carrier) and the device should do the same.

Upon the reception of NH_{ADD,DEL} events, add or remove a nexthop from
the device's adjacency table and refresh all the routes using the
nexthop group. If all the nexthops of a multipath route are invalid,
then any packet hitting the route would be trapped to the CPU for
forwarding.

If all the nexthops are DEAD, then the kernel would remove the route
entirely. On the other hand, if all the nexthops are merely LINKDOWN,
then the kernel would keep the route and forward any incoming packet
using a different route.

While the last case might sound like a problem, it's expected that a
routing daemon running in user space would remove such a route from the
FIB as it's dumped with the DEAD flag set.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The device can have one of three actions associated with a route:

1) Remote - packets continue to the adjacency table
2) Local - packets continue to the neighbour table
3) Trap - packets continue to the CPU

The first two actions can also trap packets to the CPU, but they do so
using a different trap ID, which has a lower traffic class and less
allotted bandwidth.

We currently use the third action for both RTN_{LOCAL,BROADCAST} routes
and RTN_UNICAST routes not pointing to the switch ports.

However, packets that merely need to be forwarded by the switch are
likely not control packets and can be therefore scheduled towards the
CPU using a lower traffic class.

Achieve the above by assigning the third action only to local and
broadcast routes and have any other route use either of the first two
actions, based on whether the route is gatewayed or not.

This will also allow us to refresh routes using the local action and
have them trap packets when their RIF is no longer valid following a
NH_DEL event.

One side effect of this patch is that we no longer give special
treatment to multipath routes using both switch and non-switch ports
towards their nexthops. If at least one of the nexthops can be resolved,
then the device will forward the packets instead of trapping them.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The previous patch introduced a generic function to determine whether a
route should be offloaded or not. Make use of it here.

In the future we're going to add more conditions to this test (e.g.,
whether TOS is non-zero), so it makes sense to centralize it instead of
open coding it in a few places.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We currently set the RTNH_F_OFFLOAD flag for all routes using remote
action, but this isn't always correct. If none of the nexthops
associated with a gatewayed route can be offloaded into the device, then
any packet hitting it would be trapped to the CPU and forwarded by the
kernel.

Solve this by pushing the setting of the offload flag to after the route
was programmed into the device, thereby allowing us to take all the
parameters into account.

This change will also help us further in the patchset, when we refresh
routes following the reception of NH_{ADD,DEL} events.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The nexthop init and de-init functions both have symmetric parts
concerned with the reflection of the neighbour entry into the device's
adjacency table, in case it's used by a gatewayed route.

These sections of code also need to be called when a nexthop is marked
as valid / invalid following NH_{ADD,DEL} events. Break these out into
appropriate functions, so that they could be invoked following the
reception of above events.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After the previous changes, the FIB info is embedded in every nexthop
group struct, which in turn is embedded in every FIB entry struct.

We can therefore safely remove the FIB info from the entry struct. This
has the added advantage of making the router-related structs more
generic and suitable for use with IPv6 offloads.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Up until now, the only FIB entries that were associated with a nexthop
group were routes to remote networks where all the nexthop devices had a
valid router interface (RIF). This is in contrast to the FIB code,
where all the routes are associated with a FIB info. The same design
choice needs to be applied to the driver's cache.

Based on the NH_{ADD,DEL} events which will be added later in the
patchset, we need to be able to change the action (forward / trap)
associated with all the routes using the nexthop group. However, if we
can't link between the nexthop and the routes using it, then the above
is impossible.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The next patch is going to generalize the way in which we store routes.
Instead of attaching a nexthop group only to gatewayed routes, one will
be attached to each route, in a similar way to the way the FIB code
stores its routes.

The above means that any function operating on a nexthop group cannot
assume the group represents only gatewayed nexthops. One such function
is the one that refreshes a nexthop group and updates the adjacency
table following nexthop changes.

For a nexthop group that doesn't represent any gateways this function
would essentially be a NOP, but it would be useful if it did update the
action associated with any route using it. This will allow us to later
consolidate code paths when a nexthop changes following NH_{ADD,DEL}
events.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We currently use the scope of the FIB info to distinguish between a
direct unicast route and a gatewayed one. However, the kernel is
perfectly happy to configure a route with scope UNIVERSE to a directly
connected network.

Instead, we can rely on the first nexthop's scope to check if the route
is gatewayed or not.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Later in the patchset we'll add the NH_{ADD,DEL} events which will let
us know when a nexthop is considered to be dead. Based on these events
we need to be able to add or remove the nexthop from the device's
tables.

Therefore, store the private nexthop structs in a hash table and use the
kernel's fib_nh struct as the key, so that we'll be able to easily find
them when the events are received.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, when we're notified about a new RTN_UNICAST route we perform
a lookup on the nexthop group list looking for a group with a matching
configuration to that found in the FIB info. This is quite inefficient.

Instead, we can simply rely on the kernel to consolidate several FIB
configurations into the same FIB info and use the FIB info as the key
for our private nexthop group struct.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When we invalidate a nexthop we should also invalidate its neighbour
entry pointer as it might be destroyed later on. This makes the nexthop
de-init function symmetric with its init and also ensures nobody will
try to access the neighbour entry.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We periodically ask the neighbouring system to try and resolve
neighbours that are used for nexthops, but aren't currently resolved.

However, 'nud_state' is protected by the neighbour lock, so we shouldn't
access it without taking it. Instead, we can simply check the
'connected' field of the neighbour entry, which we update upon
NEIGH_UPDATE events.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We only add neighbour entries that are also used for nexthops to
'nexthop_neighs_list', so when iterating over this list there's no need
to check that the entry is indeed used for nexthops.

Remove the redundant check.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Up until now we had two interfaces for neighbour related configuration:
ndo_neigh_{construct,destroy} and NEIGH_UPDATE netevents. The ndos were
used to add and remove neighbours from the driver's cache, whereas the
netevent was used to reflect the neighbours into the device's tables.

However, if the NUD state of a neighbour isn't NUD_VALID or if the
neighbour is dead, then there's really no reason for us to keep it
inside our cache. The only exception to this rule are neighbours that
are also used for nexthops, which we periodically refresh to get them
resolved.

We can therefore eliminate the ndo entry point into the driver and
simplify the code, making it similar to the FIB reflection, which is
based solely on events. This also helps us avoid a locking issue, in
which the RIF cache was traversed without proper locking during
insertion into the neigh entry cache.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit 33b1341c ("mlxsw: spectrum_router: Fix handling of
neighbour structure") we no longer use destination IP for neighbour
lookup, so remove it.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We currently associate each neighbour entry with a work item, so it's
not possible to have multiple events queued for the same neighbour
entry. However, this is about to be changed so that the neighbour entry
is only resolved when the work item is scheduled.

The above can result in a mismatch between the kernel's and the device's
neighbour table, unless the associated work items are processed in the
order in which they were submitted.

Do that by migrating the NEIGH_UPDATE work items to be processed in the
ordered workqueue which was recently introduced in mlxsw in commit
a3832b31 ("mlxsw: core: Create an ordered workqueue for FIB
offload").
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We always use zero delay before queueing a work on the ordered workqueue
('mlxsw_owq'), so use work_struct directly instead of delayable work.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

mlxsw_sp_nexthop_group_mac_update() is called in one of two cases:

1) When the MAC of a nexthop needs to be updated
2) When the size of a nexthop group has changed

In the second case the adjacency entries for the nexthop group need to
be reallocated from the adjacency table. In this case we must write to
the entries the MAC addresses of all the nexthops that should be
offloaded and not only those whose MAC changed. Otherwise, these entries
would be filled with garbage data, resulting in packet loss.

Fixes: a7ff87ac ("mlxsw: spectrum_router: Implement next-hop routing")
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

At the end of the nexthop initialization process we determine whether
the nexthop should be offloaded or not based on the NUD state of the
neighbour representing it. After all the nexthops were initialized we
refresh the nexthop group and potentially offload it to the device, in
case some of the nexthops were resolved.

Make the destruction of a nexthop group symmetric with its creation by
marking all nexthops as invalid and then refresh the nexthop group to
make sure it was removed from the device's tables.

Fixes: b2157149 ("mlxsw: spectrum_router: Add the nexthop neigh activity update")
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a neighbour is considered to be dead, we should remove it from the
device's table regardless of its NUD state.

Without this patch, after setting a port to be administratively down we
get the following errors when we periodically try to update the kernel
about neighbours activity:

[  461.947268] mlxsw_spectrum 0000:03:00.0 sw1p3: Failed to find
matching neighbour for IP=192.168.100.2

Fixes: a6bf9e93 ("mlxsw: spectrum_router: Offload neighbours based on NUD state change")
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit b90eb754 ("fib: introduce FIB notification infrastructure")
introduced a new notification chain to notify listeners (f.e., switchdev
drivers) about addition and deletion of routes.

However, upon registration to the chain the FIB tables can already be
populated, which means potential listeners will have an incomplete view
of the tables.

Solve that by dumping the FIB tables and replaying the events to the
passed notification block. The dump itself is done using RCU in order
not to starve consumers that need RTNL to make progress.

The integrity of the dump is ensured by reading the FIB change sequence
counter before and after the dump under RTNL. This allows us to avoid
the problematic situation in which the dumping process sends a ENTRY_ADD
notification following ENTRY_DEL generated by another process holding
RTNL.

Callers of the registration function may pass a callback that is
executed in case the dump was inconsistent with current FIB tables.

The number of retries until a consistent dump is achieved is set to a
fixed number to prevent callers from looping for long periods of time.
In case current limit proves to be problematic in the future, it can be
easily converted to be configurable using a sysctl.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

FIB offload is currently done in process context with RTNL held, but
we're about to dump the FIB tables in RCU critical section, so we can no
longer sleep.

Instead, defer the operation to process context using deferred work. Make
sure fib info isn't freed while the work is queued by taking a reference
on it and releasing it after the operation is done.

Deferring the operation is valid because the upper layers always assume
the operation was successful. If it's not, then the driver-specific
abort mechanism is called and all routed traffic is directed to slow
path.

The work items are submitted to an ordered workqueue to prevent a
mismatch between the kernel's FIB table and the device's.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The recent merge commit bb598c1b ("Merge
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net") would cause
the FIB abort warning to fire whenever we flush the FIB tables - either
during module removal or actual abort.

Move it back to its rightful location in the FIB abort function.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit b45f64d1 ("mlxsw: spectrum_router: Use FIB notifications
instead of switchdev calls") we reflect to the device the entire FIB
table and not only FIBs that point to netdevs created by the driver.

During module removal, FIBs of the second type are removed following
NETDEV_UNREGISTER events sent. The other FIBs are still present in both
the driver's cache and the device's table.

Fix this by iterating over all the FIB tables in the device and flush
them. There's no need to take locks, as we're the only writer.

Fixes: b45f64d1 ("mlxsw: spectrum_router: Use FIB notifications instead of switchdev calls")
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a warning that the abort mechanism was triggered for device.
Also avoid going through the procedure if abort was already done.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The device's neighbour table is periodically dumped in order to update
the kernel about active neighbours. A single dump session may span
multiple queries, until the response carries less records than requested
or when a record (can contain up to four neighbour entries) is not full.
Current code stops the session when the number of returned records is
zero, which can result in infinite loop in case of high packet rate.

Fix this by stopping the session according to the above logic.

Fixes: c723c735 ("mlxsw: spectrum_router: Periodically update the kernel's neigh table")
Signed-off-by: NArkadi Sharshevsky <arkadis@mellanox.com>
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since now, the table with same id in multiple netnamespaces were squashed
to a single virtual router. That is not only incorrect, it also causes
error messages when trying to use RALUE register to do double remove
of FIB entries, like this one:

mlxsw_spectrum 0000:03:00.0: EMAD reg access failed (tid=facb831c00007b20,reg_id=8013(ralue),type=write,status=7(bad parameter))

Since we don't allow ports to change namespaces (NETIF_F_NETNS_LOCAL),
and the infrastructure is not yet prepared to handle netnamespaces, just
ignore FIB notification events for non-init namespaces. That is clear to
do since we don't need to offload them.

Fixes: b45f64d1 ("mlxsw: spectrum_router: Use FIB notifications instead of switchdev calls")
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

__neigh_create function works in a different way than assumed.
It passes "n" as a parameter to ndo_neigh_construct. But this "n" might
be destroyed right away before __neigh_create() returns in case there is
already another neighbour struct in the hashtable with the same dev and
primary key. That is not expected by mlxsw_sp_router_neigh_construct()
and the stored "n" points to freed memory, eventually leading to crash.

Fix this by doing tight 1:1 coupling between neighbour struct and
internal driver neigh_entry. That allows to narrow down the key in
internal driver hashtable to do lookups by "n" only.

Fixes: 6cf3c971 ("mlxsw: spectrum_router: Add private neigh table")
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Only trees which are in use should be compared to requested prefix usage.

Fixes: 53342023 ("mlxsw: spectrum_router: Implement LPM trees management")
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>