Commit Graph

152 Commits

Author SHA1 Message Date
NeilBrown
8f0db01800 rhashtable: use bit_spin_locks to protect hash bucket.
This patch changes rhashtables to use a bit_spin_lock on BIT(1) of the
bucket pointer to lock the hash chain for that bucket.

The benefits of a bit spin_lock are:
 - no need to allocate a separate array of locks.
 - no need to have a configuration option to guide the
   choice of the size of this array
 - locking cost is often a single test-and-set in a cache line
   that will have to be loaded anyway.  When inserting at, or removing
   from, the head of the chain, the unlock is free - writing the new
   address in the bucket head implicitly clears the lock bit.
   For __rhashtable_insert_fast() we ensure this always happens
   when adding a new key.
 - even when lockings costs 2 updates (lock and unlock), they are
   in a cacheline that needs to be read anyway.

The cost of using a bit spin_lock is a little bit of code complexity,
which I think is quite manageable.

Bit spin_locks are sometimes inappropriate because they are not fair -
if multiple CPUs repeatedly contend of the same lock, one CPU can
easily be starved.  This is not a credible situation with rhashtable.
Multiple CPUs may want to repeatedly add or remove objects, but they
will typically do so at different buckets, so they will attempt to
acquire different locks.

As we have more bit-locks than we previously had spinlocks (by at
least a factor of two) we can expect slightly less contention to
go with the slightly better cache behavior and reduced memory
consumption.

To enhance type checking, a new struct is introduced to represent the
  pointer plus lock-bit
that is stored in the bucket-table.  This is "struct rhash_lock_head"
and is empty.  A pointer to this needs to be cast to either an
unsigned lock, or a "struct rhash_head *" to be useful.
Variables of this type are most often called "bkt".

Previously "pprev" would sometimes point to a bucket, and sometimes a
->next pointer in an rhash_head.  As these are now different types,
pprev is NULL when it would have pointed to the bucket. In that case,
'blk' is used, together with correct locking protocol.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-07 19:12:12 -07:00
David S. Miller
fa7f3a8d56 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Completely minor snmp doc conflict.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-21 14:41:32 -08:00
Ido Schimmel
710ae72877 net: bridge: Mark FDB entries that were added by user as such
Externally learned entries can be added by a user or by a switch driver
that is notifying the bridge driver about entries that were learned in
hardware.

In the first case, the entries are not marked with the 'added_by_user'
flag, which causes switch drivers to ignore them and not offload them.

The 'added_by_user' flag can be set on externally learned FDB entries
based on the 'swdev_notify' parameter in br_fdb_external_learn_add(),
which effectively means if the created / updated FDB entry was added by
a user or not.

Fixes: 816a3bed95 ("switchdev: Add fdb.added_by_user to switchdev notifications")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-by: Alexander Petrovskiy <alexpe@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Cc: bridge@lists.linux-foundation.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-18 15:12:16 -08:00
Petr Machata
87b0984ebf net: Add extack argument to ndo_fdb_add()
Drivers may not be able to support certain FDB entries, and an error
code is insufficient to give clear hints as to the reasons of rejection.

In order to make it possible to communicate the rejection reason, extend
ndo_fdb_add() with an extack argument. Adapt the existing
implementations of ndo_fdb_add() to take the parameter (and ignore it).
Pass the extack parameter when invoking ndo_fdb_add() from rtnl_fdb_add().

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:18:47 -08:00
Roopa Prabhu
4767456212 bridge: support for ndo_fdb_get
This patch implements ndo_fdb_get for the bridge
fdb.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-16 14:42:34 -08:00
Petr Machata
43920edf3b bridge: Add br_fdb_clear_offload()
When a driver unoffloads all FDB entries en bloc, it's inefficient to
send the switchdev notification one by one. Add a helper that unsets the
offload flag on FDB entries on a given bridge port and VLAN.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-07 12:59:08 -08:00
Ido Schimmel
e9ba0fbc7d bridge: switchdev: Allow clearing FDB entry offload indication
Currently, an FDB entry only ceases being offloaded when it is deleted.
This changes with VxLAN encapsulation.

Devices capable of performing VxLAN encapsulation usually have only one
FDB table, unlike the software data path which has two - one in the
bridge driver and another in the VxLAN driver.

Therefore, bridge FDB entries pointing to a VxLAN device are only
offloaded if there is a corresponding entry in the VxLAN FDB.

Allow clearing the offload indication in case the corresponding entry
was deleted from the VxLAN FDB.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-17 17:45:08 -07:00
Nikolay Aleksandrov
1288aa7af2 net: bridge: explicitly zero is_sticky in fdb_create
We need to explicitly zero is_sticky when creating a new fdb, otherwise
we might get a stale value for a new entry.

Fixes: 435f2e7cc0 ("net: bridge: add support for sticky fdb entries")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-28 10:43:11 -07:00
Nikolay Aleksandrov
435f2e7cc0 net: bridge: add support for sticky fdb entries
Add support for entries which are "sticky", i.e. will not change their port
if they show up from a different one. A new ndm flag is introduced for that
purpose - NTF_STICKY. We allow to set it only to non-local entries.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-12 20:30:03 -07:00
Petr Machata
873aca2ee8 net: bridge: Fix locking in br_fdb_find_port()
Callers of br_fdb_find() need to hold the hash lock, which
br_fdb_find_port() doesn't do. However, since br_fdb_find_port() is not
doing any actual FDB manipulation, the hash lock is not really needed at
all. So convert to br_fdb_find_rcu(), surrounded by rcu_read_lock() /
_unlock() pair.

The device pointer copied from inside the FDB entry is then kept alive
by the RTNL lock, which br_fdb_find_port() asserts.

Fixes: 4d4fd36126 ("net: bridge: Publish bridge accessor functions")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-08 19:58:31 -04:00
Petr Machata
161d82de1f net: bridge: Notify about !added_by_user FDB entries
Do not automatically bail out on sending notifications about activity on
non-user-added FDB entries. Instead, notify about this activity except
for cases where the activity itself originates in a notification, to
avoid sending duplicate notifications.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:46:47 -04:00
Petr Machata
4d4fd36126 net: bridge: Publish bridge accessor functions
Add a couple new functions to allow querying FDB and vlan settings of a
bridge.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-30 12:42:40 -04:00
Geert Uytterhoeven
367dc6586d net: bridge: Fix uninitialized error in br_fdb_sync_static()
With gcc-4.1.2.:

    net/bridge/br_fdb.c: In function ‘br_fdb_sync_static’:
    net/bridge/br_fdb.c:996: warning: ‘err’ may be used uninitialized in this function

Indeed, if the list is empty, err will be uninitialized, and will be
propagated up as the function return value.

Fix this by preinitializing err to zero.

Fixes: eb7935830d ("net: bridge: use rhashtable for fdbs")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-01 09:47:37 -05:00
Nikolay Aleksandrov
eb7935830d net: bridge: use rhashtable for fdbs
Before this patch the bridge used a fixed 256 element hash table which
was fine for small use cases (in my tests it starts to degrade
above 1000 entries), but it wasn't enough for medium or large
scale deployments. Modern setups have thousands of participants in a
single bridge, even only enabling vlans and adding a few thousand vlan
entries will cause a few thousand fdbs to be automatically inserted per
participating port. So we need to scale the fdb table considerably to
cope with modern workloads, and this patch converts it to use a
rhashtable for its operations thus improving the bridge scalability.
Tests show the following results (10 runs each), at up to 1000 entries
rhashtable is ~3% slower, at 2000 rhashtable is 30% faster, at 3000 it
is 2 times faster and at 30000 it is 50 times faster.
Obviously this happens because of the properties of the two constructs
and is expected, rhashtable keeps pretty much a constant time even with
10000000 entries (tested), while the fixed hash table struggles
considerably even above 10000.
As a side effect this also reduces the net_bridge struct size from 3248
bytes to 1344 bytes. Also note that the key struct is 8 bytes.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 15:10:01 -05:00
Roopa Prabhu
e3cfddd577 bridge: add tracepoint in br_fdb_update
This extends bridge fdb table tracepoints to also cover
learned fdb entries in the br_fdb_update path. Note that
unlike other tracepoints I have moved this to when the fdb
is modified because this is in the datapath and can generate
a lot of noise in the trace output. br_fdb_update is also called
from added_by_user context in the NTF_USE case which is already
traced ..hence the !added_by_user check.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-31 11:42:41 -07:00
Roopa Prabhu
b74fd306ef bridge: fdb add and delete tracepoints
A few useful tracepoints to trace bridge forwarding
database updates.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-29 14:49:45 -07:00
Arkadi Sharshevsky
3a83c2a7a5 net: bridge: Remove FDB deletion through switchdev object
At this point no driver supports FDB add/del through switchdev object
but rather via notification chain, thus, it is removed.

Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Ivan Vecera <ivecera@redhat.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-07 14:48:48 -07:00
Nikolay Aleksandrov
7597b266c5 bridge: allow ext learned entries to change ports
current code silently ignores change of port in the request
message. This patch makes sure the port is modified and
notification is sent to userspace.

Fixes: cf6b8e1eed ("bridge: add API to notify bridge driver of learned FBD on offloaded device")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-04 01:49:44 -07:00
Arkadi Sharshevsky
9fe8bcec0d net: bridge: Receive notification about successful FDB offload
When a new static FDB is added to the bridge a notification is sent to
the driver for offload. In case of successful offload the driver should
notify the bridge back, which in turn should mark the FDB as offloaded.

Currently, externally learned is equivalent for being offloaded which is
not correct due to the fact that FDBs which are added from user-space are
also marked as externally learned. In order to specify if an FDB was
successfully offloaded a new flag is introduced.

Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08 14:16:25 -04:00
Arkadi Sharshevsky
6b26b51b1d net: bridge: Add support for notifying devices about FDB add/del
Currently the bridge doesn't notify the underlying devices about new
FDBs learned. The FDB sync is placed on the switchdev notifier chain
because devices may potentially learn FDB that are not directly related
to their ports, for example:

1. Mixed SW/HW bridge - FDBs that point to the ASICs external devices
                        should be offloaded as CPU traps in order to
			perform forwarding in slow path.
2. EVPN - Externally learned FDBs for the vtep device.

Notification is sent only about static FDB add/del. This is done due
to fact that currently this is the only scenario supported by switch
drivers.

Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08 14:16:25 -04:00
Arkadi Sharshevsky
0baa10fff2 net: bridge: Add support for calling FDB external learning under rcu
This is done as a preparation to moving the switchdev notifier chain
to be atomic. The FDB external learning should be called under rtnl
or rcu.

Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08 14:16:24 -04:00
Arkadi Sharshevsky
58073b32b0 net: bridge: Fix improper taking over HW learned FDB
Commit 7e26bf45e4 ("net: bridge: allow SW learn to take over HW fdb
entries") added the ability to "take over an entry which was previously
learned via HW when it shows up from a SW port".

However, if an entry was learned via HW and then a control packet
(e.g., ARP request) was trapped to the CPU, the bridge driver will
update the entry and remove the externally learned flag, although the
entry is still present in HW. Instead, only clear the externally learned
flag in case of roaming.

Fixes: 7e26bf45e4 ("net: bridge: allow SW learn to take over HW fdb entries")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Arkadi Sharashevsky <arkadis@mellanox.com>
Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-30 22:46:32 -04:00
Nikolay Aleksandrov
cab93af0ed net: bridge: notify on hw fdb takeover
Recently we added support for SW fdbs to take over HW ones, but that
results in changing a user-visible fdb flag thus we need to send a
notification, also it's consistent with how HW takes over SW entries.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-17 13:45:34 -04:00
Nikolay Aleksandrov
eb100e0e24 net: bridge: allow to add externally learned entries from user-space
The NTF_EXT_LEARNED flag was added for switchdev and externally learned
entries, but it can also be used for entries learned via a software
in user-space which requires dynamic entries that do not expire.
One such case that we have is with quagga and evpn which need dynamic
entries but also require to age them themselves.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-24 12:30:21 -07:00
Nikolay Aleksandrov
7e26bf45e4 net: bridge: allow SW learn to take over HW fdb entries
Allow to take over an entry which was previously learned via HW when it
shows up from a SW port. This is analogous to how HW takes over SW learned
entries already.

Suggested-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-24 12:30:21 -07:00
WANG Cong
d12c917691 bridge: resolve a false alarm of lockdep
Andrei reported a false alarm of lockdep at net/bridge/br_fdb.c:109,
this is because in Andrei's case, a spin_bug() was already triggered
before this, therefore the debug_locks is turned off, lockdep_is_held()
is no longer accurate after that. We should use lockdep_assert_held_once()
instead of lockdep_is_held() to respect debug_locks.

Fixes: 410b3d48f5 ("bridge: fdb: add proper lock checks in searching functions")
Reported-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-16 21:29:20 -07:00
Roopa Prabhu
eda7a5e88d bridge: don't indicate expiry on NTF_EXT_LEARNED fdb entries
added_by_external_learn fdb entries are added and expired by
external entities like switchdev driver or external controllers.
ageing is already disabled for such entries. Hence, don't
indicate expiry for such fdb entries.

CC: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Tested-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-17 13:56:56 -05:00
Nikolay Aleksandrov
5019ab50f2 bridge: fdb: converge fdb_delete_by functions into one
We can simplify the logic of entries pointing to the bridge by
converging the fdb_delete_by functions, this would allow us to use the
same function for both cases since the fdb's dst is set to NULL if it is
pointing to the bridge thus we can always check for a port match.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-14 12:41:03 -05:00
Nikolay Aleksandrov
410b3d48f5 bridge: fdb: add proper lock checks in searching functions
In order to avoid new errors add checks to br_fdb_find and fdb_find_rcu
functions. The first requires hash_lock, the second obviously RCU.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-14 12:41:03 -05:00
Nikolay Aleksandrov
bfd0aeac52 bridge: fdb: converge fdb searching functions into one
Before this patch we had 3 different fdb searching functions which was
confusing. This patch reduces all of them to one - fdb_find_rcu(), and
two flavors: br_fdb_find() which requires hash_lock and br_fdb_find_rcu
which requires RCU. This makes it clear what needs to be used, we also
remove two abusers of __br_fdb_get which called it under hash_lock and
replace them with br_fdb_find().

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-14 12:41:02 -05:00
stephen hemminger
ca6d4480f8 bridge: avoid unnecessary read of jiffies
Jiffies is volatile so read it once.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 14:16:05 -05:00
Nikolay Aleksandrov
83a718d629 bridge: fdb: write to used and updated at most once per jiffy
Writing once per jiffy is enough to limit the bridge's false sharing.
After this change the bridge doesn't show up in the local load HitM stats.

Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-06 22:53:13 -05:00
Nikolay Aleksandrov
f7cdee8a79 bridge: move to workqueue gc
Move the fdb garbage collector to a workqueue which fires at least 10
milliseconds apart and cleans chain by chain allowing for other tasks
to run in the meantime. When having thousands of fdbs the system is much
more responsive. Most importantly remove the need to check if the
matched entry has expired in __br_fdb_get that causes false-sharing and
is completely unnecessary if we cleanup entries, at worst we'll get 10ms
of traffic for that entry before it gets deleted.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-06 22:53:13 -05:00
Roopa Prabhu
de1dfeefef bridge: add address and vlan to fdb warning messages
This patch adds vlan and address to warning messages printed
in the bridge fdb code for debuggability.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-13 10:49:54 -04:00
Roopa Prabhu
d297653dd6 rtnetlink: fdb dump: optimize by saving last interface markers
fdb dumps spanning multiple skb's currently restart from the first
interface again for every skb. This results in unnecessary
iterations on the already visited interfaces and their fdb
entries. In large scale setups, we have seen this to slow
down fdb dumps considerably. On a system with 30k macs we
see fdb dumps spanning across more than 300 skbs.

To fix the problem, this patch replaces the existing single fdb
marker with three markers: netdev hash entries, netdevs and fdb
index to continue where we left off instead of restarting from the
first netdev. This is consistent with link dumps.

In the process of fixing the performance issue, this patch also
re-implements fix done by
commit 472681d57a ("net: ndo_fdb_dump should report -EMSGSIZE to rtnl_fdb_dump")
(with an internal fix from Wilson Kok) in the following ways:
- change ndo_fdb_dump handlers to return error code instead
of the last fdb index
- use cb->args strictly for dump frag markers and not error codes.
This is consistent with other dump functions.

Below results were taken on a system with 1000 netdevs
and 35085 fdb entries:
before patch:
$time bridge fdb show | wc -l
15065

real    1m11.791s
user    0m0.070s
sys 1m8.395s

(existing code does not return all macs)

after patch:
$time bridge fdb show | wc -l
35085

real    0m2.017s
user    0m0.113s
sys 0m1.942s

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Wilson Kok <wkok@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 16:56:15 -07:00
Toshiaki Makita
7bb90c3715 bridge: Fix problems around fdb entries pointing to the bridge device
Adding fdb entries pointing to the bridge device uses fdb_insert(),
which lacks various checks and does not respect added_by_user flag.

As a result, some inconsistent behavior can happen:
* Adding temporary entries succeeds but results in permanent entries.
* Same goes for "dynamic" and "use".
* Changing mac address of the bridge device causes deletion of
  user-added entries.
* Replacing existing entries looks successful from userspace but actually
  not, regardless of NLM_F_EXCL flag.

Use the same logic as other entries and fix them.

Fixes: 3741873b4f ("bridge: allow adding of fdb entries pointing to the bridge device")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-09 21:42:44 -07:00
Toshiaki Makita
0b148def40 bridge: Don't insert unnecessary local fdb entry on changing mac address
The missing br_vlan_should_use() test caused creation of an unneeded
local fdb entry on changing mac address of a bridge device when there is
a vlan which is configured on a bridge port but not on the bridge
device.

Fixes: 2594e9064a ("bridge: vlan: add per-vlan struct and move to rhashtables")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08 00:31:38 -07:00
MINOURA Makoto / 箕浦 真
472681d57a net: ndo_fdb_dump should report -EMSGSIZE to rtnl_fdb_dump.
When the send skbuff reaches the end, nlmsg_put and friends returns
-EMSGSIZE but it is silently thrown away in ndo_fdb_dump. It is called
within a for_each_netdev loop and the first fdb entry of a following
netdev could fit in the remaining skbuff.  This breaks the mechanism
of cb->args[0] and idx to keep track of the entries that are already
dumped, which results missing entries in bridge fdb show command.

Signed-off-by: Minoura Makoto <minoura@valinux.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-26 15:04:02 -05:00
Ido Schimmel
6ff64f6f92 switchdev: Pass original device to port netdev driver
switchdev drivers need to know the netdev on which the switchdev op was
invoked. For example, the STP state of a VLAN interface configured on top
of a port can change while being member in a bridge. In this case, the
underlying driver should only change the STP state of that particular
VLAN and not of all the VLANs configured on the port.

However, current switchdev infrastructure only passes the port netdev down
to the driver. Solve that by passing the original device down to the
driver as part of the required switchdev object / attribute.

This doesn't entail any change in current switchdev drivers. It simply
enables those supporting stacked devices to know the originating device
and act accordingly.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15 11:58:20 -05:00
Roopa Prabhu
b7af1472af bridge: set is_local and is_static before fdb entry is added to the fdb hashtable
Problem Description:
We can add fdbs pointing to the bridge with NULL ->dst but that has a
few race conditions because br_fdb_insert() is used which first creates
the fdb and then, after the fdb has been published/linked, sets
"is_local" to 1 and in that time frame if a packet arrives for that fdb
it may see it as non-local and either do a NULL ptr dereference in
br_forward() or attach the fdb to the port where it arrived, and later
br_fdb_insert() will make it local thus getting a wrong fdb entry.
Call chain br_handle_frame_finish() -> br_forward():
But in br_handle_frame_finish() in order to call br_forward() the dst
should not be local i.e. skb != NULL, whenever the dst is
found to be local skb is set to NULL so we can't forward it,
and here comes the problem since it's running only
with RCU when forwarding packets it can see the entry before "is_local"
is set to 1 and actually try to dereference NULL.
The main issue is that if someone sends a packet to the switch while
it's adding the entry which points to the bridge device, it may
dereference NULL ptr. This is needed now after we can add fdbs
pointing to the bridge.  This poses a problem for
br_fdb_update() as well, while someone's adding a bridge fdb, but
before it has is_local == 1, it might get moved to a port if it comes
as a source mac and then it may get its "is_local" set to 1

This patch changes fdb_create to take is_local and is_static as
arguments to set these values in the fdb entry before it is added to the
hash. Also adds null check for port in br_forward.

Fixes: 3741873b4f ("bridge: allow adding of fdb entries pointing to the bridge device")
Reported-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-30 12:13:05 +09:00
Jiri Pirko
56607386e8 bridge: defer switchdev fdb del call in fdb_del_external_learn
Since spinlock is held here, defer the switchdev operation. Also, ensure
that defered switchdev ops are processed before port master device
is unlinked.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-15 06:09:50 -07:00
Jiri Pirko
850d0cbc91 switchdev: remove pointers from switchdev objects
When object is used in deferred work, we cannot use pointers in
switchdev object structures because the memory they point at may be already
used by someone else. So rather do local copy of the value.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-15 06:09:49 -07:00
Roopa Prabhu
3741873b4f bridge: allow adding of fdb entries pointing to the bridge device
This patch enables adding of fdb entries pointing to the bridge device.
This can be used to propagate mac address of vlan interfaces
configured on top of the vlan filtering bridge.

Before:
$bridge fdb add 44:38:39:00:27:9f dev bridge
RTNETLINK answers: Invalid argument

After:
$bridge fdb add 44:38:39:00:27:9f dev bridge

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12 05:11:58 -07:00
Jiri Pirko
9e8f4a548a switchdev: push object ID back to object structure
Suggested-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:40 -07:00
Jiri Pirko
648b4a995a switchdev: bring back switchdev_obj and use it as a generic object param
Replace "void *obj" with a generic structure. Introduce couple of
helpers along that.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:39 -07:00
Jiri Pirko
52ba57cfdc switchdev: rename switchdev_obj_fdb to switchdev_obj_port_fdb
Make the struct name in sync with object id name.

Suggested-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:39 -07:00
Jiri Pirko
57d80838da switchdev: rename SWITCHDEV_OBJ_* enum values to SWITCHDEV_OBJ_ID_*
Suggested-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:36 -07:00
Vivien Didelot
ab06900230 net: switchdev: abstract object in add/del ops
Similar to the notifier_call callback of a notifier_block, change the
function signature of switchdev add and del operations to:

    int switchdev_port_obj_add/del(struct net_device *dev,
                                   enum switchdev_obj_id id, void *obj);

This allows the caller to pass a specific switchdev_obj_* structure
instead of the generic switchdev_obj one.

Drivers implementation of these operations and switchdev have been
changed accordingly.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 21:31:59 -07:00
Nikolay Aleksandrov
2594e9064a bridge: vlan: add per-vlan struct and move to rhashtables
This patch changes the bridge vlan implementation to use rhashtables
instead of bitmaps. The main motivation behind this change is that we
need extensible per-vlan structures (both per-port and global) so more
advanced features can be introduced and the vlan support can be
extended. I've tried to break this up but the moment net_port_vlans is
changed and the whole API goes away, thus this is a larger patch.
A few short goals of this patch are:
- Extensible per-vlan structs stored in rhashtables and a sorted list
- Keep user-visible behaviour (compressed vlans etc)
- Keep fastpath ingress/egress logic the same (optimizations to come
  later)

Here's a brief list of some of the new features we'd like to introduce:
- per-vlan counters
- vlan ingress/egress mapping
- per-vlan igmp configuration
- vlan priorities
- avoid fdb entries replication (e.g. local fdb scaling issues)

The structure is kept single for both global and per-port entries so to
avoid code duplication where possible and also because we'll soon introduce
"port0 / aka bridge as port" which should simplify things further
(thanks to Vlad for the suggestion!).

Now we have per-vlan global rhashtable (bridge-wide) and per-vlan port
rhashtable, if an entry is added to a port it'll get a pointer to its
global context so it can be quickly accessed later. There's also a
sorted vlan list which is used for stable walks and some user-visible
behaviour such as the vlan ranges, also for error paths.
VLANs are stored in a "vlan group" which currently contains the
rhashtable, sorted vlan list and the number of "real" vlan entries.
A good side-effect of this change is that it resembles how hw keeps
per-vlan data.
One important note after this change is that if a VLAN is being looked up
in the bridge's rhashtable for filtering purposes (or to check if it's an
existing usable entry, not just a global context) then the new helper
br_vlan_should_use() needs to be used if the vlan is found. In case the
lookup is done only with a port's vlan group, then this check can be
skipped.

Things tested so far:
- basic vlan ingress/egress
- pvids
- untagged vlans
- undef CONFIG_BRIDGE_VLAN_FILTERING
- adding/deleting vlans in different scenarios (with/without global ctx,
  while transmitting traffic, in ranges etc)
- loading/removing the module while having/adding/deleting vlans
- extracting bridge vlan information (user ABI), compressed requests
- adding/deleting fdbs on vlans
- bridge mac change, promisc mode
- default pvid change
- kmemleak ON during the whole time

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 13:36:06 -07:00
Siva Mannem
dcd45e0649 bridge: don't age externally added FDB entries
Signed-off-by: Siva Mannem <siva.mannem.lnx@gmail.com>
Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Premkumar Jonnala <pjonnala@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-23 14:35:58 -07:00