In rare cases during shutdown the following general protection fault can
happen:
general protection fault: 0000 [#1] SMP
Modules linked in: batman_adv(O-) [...]
CPU: 3 PID: 1714 Comm: rmmod Tainted: G O 4.6.0-rc6+ #1
[...]
Call Trace:
[<ffffffffa0363294>] batadv_hardif_disable_interface+0x29a/0x3a6 [batman_adv]
[<ffffffffa0373db4>] batadv_softif_destroy_netlink+0x4b/0xa4 [batman_adv]
[<ffffffff813b52f3>] __rtnl_link_unregister+0x48/0x92
[<ffffffff813b9240>] rtnl_link_unregister+0xc1/0xdb
[<ffffffff8108547c>] ? bit_waitqueue+0x87/0x87
[<ffffffffa03850d2>] batadv_exit+0x1a/0xf48 [batman_adv]
[<ffffffff810c26f9>] SyS_delete_module+0x136/0x1b0
[<ffffffff8144dc65>] entry_SYSCALL_64_fastpath+0x18/0xa8
[<ffffffff8108aaca>] ? trace_hardirqs_off_caller+0x37/0xa6
Code: 89 f7 e8 21 bd 0d e1 4d 85 e4 75 0e 31 f6 48 c7 c7 50 d7 3b a0 e8 50 16 f2 e0 49 8b 9c 24 28 01 00 00 48 85 db 0f 84 b2 00 00 00 <48> 8b 03 4d 85 ed 48 89 45 c8 74 09 4c 39 ab f8 00 00 00 75 1c
RIP [<ffffffffa0371852>] batadv_purge_outstanding_packets+0x1c8/0x291 [batman_adv]
RSP <ffff88001da5fd78>
---[ end trace 803b9bdc6a4a952b ]---
Kernel panic - not syncing: Fatal exception in interrupt
Kernel Offset: disabled
---[ end Kernel panic - not syncing: Fatal exception in interrupt
It does not happen often, but may potentially happen when frequently
shutting down and reinitializing an interface. With some carefully
placed msleep()s/mdelay()s it can be reproduced easily.
The issue is, that on interface removal, any still running worker thread
of a forwarding packet will race with the interface purging routine to
free a forwarding packet. Temporarily giving up a spin-lock to be able
to sleep in the purging routine is not safe.
Furthermore, there is a potential general protection fault not just for
the purging side shown above, but also on the worker side: Temporarily
removing a forw_packet from the according forw_{bcast,bat}_list will make
it impossible for the purging routine to catch and cancel it.
# How this patch tries to fix it:
With this patch we split the queue purging into three steps: Step 1),
removing forward packets from the queue of an interface and by that
claim it as our responsibility to free.
Step 2), we are either lucky to cancel a pending worker before it starts
to run. Or if it is already running, we wait and let it do its thing,
except two things:
Through the claiming in step 1) we prevent workers from a) re-arming
themselves. And b) prevent workers from freeing packets which we still
hold in the interface purging routine.
Finally, step 3, we are sure that no forwarding packets are pending or
even running anymore on the interface to remove. We can then safely free
the claimed forwarding packets.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
In a few situations batman-adv tries to determine whether a given interface
is a WiFi interface to enable specific WiFi optimizations. If the interface
batman-adv has been configured with is a virtual interface (e.g. VLAN) it
would not be properly detected as WiFi interface and thus not benefit from
the special WiFi treatment.
This patch changes that by peeking under the hood whenever a virtual
interface is in play.
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
[sven.eckelmann@open-mesh.com: integrate in wifi_flags caching, retrieve
namespace of link interface]
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
batman-adv is requiring the type of wifi device in different contexts. Some
of them can take the rtnl semaphore and some of them already have the
semaphore taken. But even others don't allow that the semaphore will be
taken.
The data has to be retrieved when the hardif is added to batman-adv because
some of the wifi information for an hardif will only be available with rtnl
lock. It can then be cached in the batadv_hard_iface and the functions
is_wifi_netdev and is_cfg80211_netdev can just compare the correct bits
without imposing extra locking requirements.
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
With this patch, (re)broadcasting on a specific interfaces is avoided:
* No neighbor: There is no need to broadcast on an interface if there
is no node behind it.
* Single neighbor is source: If there is just one neighbor on an
interface and if this neighbor is the one we actually got this
broadcast packet from, then we do not need to echo it back.
* Single neighbor is originator: If there is just one neighbor on
an interface and if this neighbor is the originator of this
broadcast packet, then we do not need to echo it back.
Goodies for BATMAN V:
("Upgrade your BATMAN IV network to V now to get these for free!")
Thanks to the split of OGMv1 into two packet types, OGMv2 and ELP
that is, we can now apply the same optimizations stated above to OGMv2
packets, too.
Furthermore, with BATMAN V, rebroadcasts can be reduced in certain
multi interface cases, too, where BATMAN IV cannot. This is thanks to
the removal of the "secondary interface originator" concept in BATMAN V.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Instead of latching onto the OGM period, this patch introduces a worker
dedicated to multicast TT and TVLV updates.
The reasoning is, that upon roaming especially the translation table
should be updated timely to minimize connectivity issues.
With BATMAN V, the idea is to greatly increase the OGM interval to
reduce overhead. Unfortunately, right now this could lead to
a bad user experience if multicast traffic is involved.
Therefore this patch introduces a fixed 500ms update interval for
multicast TT entries and the multicast TVLV.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The batman-adv codebase is using "list" for the list node (prev/next) and
<list content descriptor>+"_list" for the head of a list. Not using this
naming scheme can up in confusions when reading the code.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The batman-adv codebase is using "list" for the list node (prev/next) and
<list content descriptor>+"_list" for the head of a list. Not using this
naming scheme can up in confusions because list_head is used for both the
head of the list and the list node (prev/next) in each item of the list.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The forw_packet list node is wrongly attributed to the icmp socket code.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The files provided by batman-adv via debugfs are currently converted to
netlink. Tools which are not yet converted to use the netlink interface may
still rely on the old debugfs files. But systems which already upgraded
their tools can save some space by disabling this feature. The default
configuration of batman-adv on amd64 can reduce the size of the module by
around 11% when this feature is disabled.
$ size net/batman-adv/batman-adv.ko*
text data bss dec hex filename
150507 10395 4160 165062 284c6 net/batman-adv/batman-adv.ko.y
137106 7099 2112 146317 23b8d net/batman-adv/batman-adv.ko.n
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Add BATADV_CMD_GET_GATEWAYS commands, using handlers bat_gw_dump in
batadv_algo_ops. Will always return -EOPNOTSUPP for now, as no
implementations exist yet.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Add BATADV_CMD_GET_ORIGINATORS and BATADV_CMD_GET_NEIGHBORS commands,
using handlers bat_orig_dump and bat_neigh_dump in batadv_algo_ops. Will
always return -EOPNOTSUPP for now, as no implementations exist yet.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
[sven@narfation.org: Rewrite based on new algo_ops structures]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
This patch abstracts the forward packet creation into the new function
batadv_forw_packet_alloc().
The queue counting and interface reference counters are now handled
internally within batadv_forw_packet_alloc() and its
batadv_forw_packet_free() counterpart. This should reduce the risk of
having reference/queue counting bugs again and should increase
code readibility.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Each routing protocol may have its own specific logic about
gateway election which is potentially based on the metric being
used.
Create two GW specific API functions and move the current election
logic in the B.A.T.M.A.N. IV specific code.
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The B.A.T.M.A.N. V algorithm uses a different metric compared to its
predecessor and for this reason the logic used to compute the best
Gateway is also changed. This means that the GW selection class
fed to this logic has a semantics that depends on the algorithm being
used.
Make the parsing and printing routine of the GW selection class
routing algorithm specific. Each algorithm can now parse (and print)
this value independently.
If no API is provided by any algorithm, the default is to use the
current mechanism of considering such value like an integer between
1 and 255.
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Postponing the removal of the interface breaks the expected behavior of
NETDEV_UNREGISTER and NETDEV_PRE_TYPE_CHANGE. This is especially
problematic when an interface is removed and added in quick succession.
This reverts commit 5bc44dc845 ("batman-adv: postpone sysfs removal when
unregistering").
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The legacy sysfs interface to modify interfaces belonging to batman-adv
is run inside a region holding s_lock. And to add a net_device, it has
to also get the rtnl_lock. This is exactly the other way around than in
other virtual net_devices and conflicts with netdevice notifier which
executes inside rtnl_lock.
The inverted lock situation is currently solved by executing the removal
of netdevices via workqueue. The workqueue isn't executed inside
rtnl_lock and thus can independently get the s_lock and the rtnl_lock.
But this workaround fails when the netdevice notifier creates events in
quick succession and the earlier triggered removal of a net_device isn't
processed in the workqueue before the adding of the new netdevice (with
same name) event is issued.
Instead the legacy sysfs interface store events have to be enqueued in
a workqueue to loose the s_lock. The worker is then free to get the
required locks and the deadlock is avoided.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Some operations in batadv_algo_ops are optional and marked as such in the
kerneldoc. But some of them miss the "(optional)" in their kerneldoc. These
have to also be marked to give an implementor of an algorithm the correct
background information without looking in the code calling these function
pointers.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The replacement of last_bonding_candidate in batadv_orig_node has to be an
atomic operation. Otherwise it is possible that the reference counter of a
batadv_orig_ifinfo is reduced which was no longer the
last_bonding_candidate when the new candidate is added. This can either
lead to an invalid memory access or to reference leaks which make it
impossible to an interface which was added to batman-adv.
Fixes: f3b3d90189 ("batman-adv: add bonding again")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The pointer batadv_bla_claim::backbone_gw can be changed at any time.
Therefore, access to it must be protected to ensure that two function
accessing the same backbone_gw are actually accessing the same. This is
especially important when the crc_lock is used or when the backbone_gw of a
claim is exchanged.
Not doing so leads to invalid memory access and/or reference leaks.
Fixes: 23721387c4 ("batman-adv: add basic bridge loop avoidance code")
Fixes: 5a1dd8a477 ("batman-adv: lock crc access in bridge loop avoidance")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
- Cleanup work by Markus Pargmann and Sven Eckelmann (six patches)
- Initial Netlink support by Matthias Schiffer (two patches)
- Throughput Meter implementation by Antonio Quartulli, a kernel-space
traffic generator to estimate link speeds. This feature is useful on
low-end WiFi APs where running iperf or netperf from userspace
gives wrong results due to heavy userspace/kernelspace overhead.
(two patches)
- API clean-up work by Antonio Quartulli (one patch)
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Merge tag 'batadv-next-for-davem-20160704' of git://git.open-mesh.org/linux-merge
Simon Wunderlich says:
====================
This feature patchset includes the following changes:
- Cleanup work by Markus Pargmann and Sven Eckelmann (six patches)
- Initial Netlink support by Matthias Schiffer (two patches)
- Throughput Meter implementation by Antonio Quartulli, a kernel-space
traffic generator to estimate link speeds. This feature is useful on
low-end WiFi APs where running iperf or netperf from userspace
gives wrong results due to heavy userspace/kernelspace overhead.
(two patches)
- API clean-up work by Antonio Quartulli (one patch)
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The routing API data structure contains several function
pointers that can easily be grouped together based on the
component they work with.
Split the API in subobjects in order to improve definition readability.
At the same time, remove the "bat_" prefix from the API object and
its fields names. These are batman-adv private structs and there is no
need to always prepend such prefix, which only makes function invocations
much much longer.
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Reviewed-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The throughput meter module is a simple, kernel-space replacement for
throughtput measurements tool like iperf and netperf. It is intended to
approximate TCP behaviour.
It is invoked through batctl: the protocol is connection oriented, with
cumulative acknowledgment and a dynamic-size sliding window.
The test *can* be interrupted by batctl. A receiver side timeout avoids
unlimited waitings for sender packets: after one second of inactivity, the
receiver abort the ongoing test.
Based on a prototype from Edo Monticelli <montik@autistici.org>
Signed-off-by: Antonio Quartulli <antonio.quartulli@open-mesh.com>
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
- two patches with minimal clean up work by Antonio Quartulli and
Simon Wunderlich
- eight patches of B.A.T.M.A.N. V, API and documentation clean
up work, by Antonio Quartulli and Marek Lindner
- Andrew Lunn fixed the skb priority adoption when forwarding
fragmented packets (two patches)
- Multicast optimization support is now enabled for bridges which
comes with some protocol updates, by Linus Luessing
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Merge tag 'batadv-next-for-davem-20160701' of git://git.open-mesh.org/linux-merge
Simon Wunderlich says:
====================
This feature patchset includes the following changes:
- two patches with minimal clean up work by Antonio Quartulli and
Simon Wunderlich
- eight patches of B.A.T.M.A.N. V, API and documentation clean
up work, by Antonio Quartulli and Marek Lindner
- Andrew Lunn fixed the skb priority adoption when forwarding
fragmented packets (two patches)
- Multicast optimization support is now enabled for bridges which
comes with some protocol updates, by Linus Luessing
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
With this patch changes relevant to a node's own multicast flags are
printed to the 'mcast' log level.
Tested-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
With this patch we are finally able to support multicast optimizations
in bridged setups, too. So far, if a bridge was added on top of a
soft-interface (e.g. bat0) the batman-adv multicast optimizations
needed to be disabled to avoid packetloss.
Current Linux bridge implementations and API can now provide us
with the so far missing information about interested but "remote"
multicast receivers behind bridge ports.
The Linux bridge performs the detection of remote participants
interested in multicast packets with its own and mature so
called IGMP and MLD snooping code and stores that in its
database. With the new API provided by the bridge batman-adv can
now simply hook into this database.
We then reliably announce the gathered multicast listeners to
other nodes through the batman-adv translation table.
Additionally, the Linux bridge provides us with the information about
whether an IGMP/MLD querier exists. If there is none then we need to
disable multicast optimizations as we cannot learn about multicast
listeners on external, bridged-in host then.
Tested-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
To reduce the field pollution in our main batadv_priv data structure
we've already created some substructures so that we could group fields
in a convenient manner.
However gw_mode and gw_sel_class are still part of the main object.
More both fields to the GW private substructure.
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The ogm_emit and ogm_schedule API calls were rather tight to the
B.A.T.M.A.N. IV logic and therefore rather difficult to use
with other algorithm implementations.
Remove such calls and move the surrounding logic into the
B.A.T.M.A.N. IV specific code.
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The tt_req_node is added and removed from a list inside a spinlock. But the
locking is sometimes removed even when the object is still referenced and
will be used later via this reference. For example batadv_send_tt_request
can create a new tt_req_node (including add to a list) and later
re-acquires the lock to remove it from the list and to free it. But at this
time another context could have already removed this tt_req_node from the
list and freed it.
CPU#0
batadv_batman_skb_recv from net_device 0
-> batadv_iv_ogm_receive
-> batadv_iv_ogm_process
-> batadv_iv_ogm_process_per_outif
-> batadv_tvlv_ogm_receive
-> batadv_tvlv_ogm_receive
-> batadv_tvlv_containers_process
-> batadv_tvlv_call_handler
-> batadv_tt_tvlv_ogm_handler_v1
-> batadv_tt_update_orig
-> batadv_send_tt_request
-> batadv_tt_req_node_new
spin_lock(...)
allocates new tt_req_node and adds it to list
spin_unlock(...)
return tt_req_node
CPU#1
batadv_batman_skb_recv from net_device 1
-> batadv_recv_unicast_tvlv
-> batadv_tvlv_containers_process
-> batadv_tvlv_call_handler
-> batadv_tt_tvlv_unicast_handler_v1
-> batadv_handle_tt_response
spin_lock(...)
tt_req_node gets removed from list and is freed
spin_unlock(...)
CPU#0
<- returned to batadv_send_tt_request
spin_lock(...)
tt_req_node gets removed from list and is freed
MEMORY CORRUPTION/SEGFAULT/...
spin_unlock(...)
This can only be solved via reference counting to allow multiple contexts
to handle the list manipulation while making sure that only the last
context holding a reference will free the object.
Fixes: a73105b8d4 ("batman-adv: improved client announcement mechanism")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Tested-by: Martin Weinelt <martin@darmstadt.freifunk.net>
Tested-by: Amadeus Alfa <amadeus@chemnitz.freifunk.net>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are network setups where the current bridge loop avoidance can't
detect bridge loops. The minimal setup affected would consist of two
LANs and two separate meshes, connected in a ring like that:
A...(mesh1)...B
| |
(LAN1) (LAN2)
| |
C...(mesh2)...D
Since both the meshes and backbones are separate, the bridge loop
avoidance has not enough information to detect and avoid the loop
in this case. Even if these scenarios can't be fixed easily,
these kind of loops can be detected.
This patch implements a periodic check (running every 60 seconds for
now) which sends a broadcast frame with a random MAC address on
each backbone VLAN. If a broadcast frame with the same MAC address
is received shortly after on the mesh, we know that there must be a
loop and report that incident as well as throw an uevent to let others
handle that problem.
Signed-off-by: Simon Wunderlich <simon.wunderlich@open-mesh.com>
[sven@narfation.org: fix conflicts with current version]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
The batadv_neigh_node was specific to a batadv_hardif_neigh_node and held
an implicit reference to it. But this reference was never stored in form of
a pointer in the batadv_neigh_node itself. Instead
batadv_neigh_node_release depends on a consistent state of
hard_iface->neigh_list and that batadv_hardif_neigh_get always returns the
batadv_hardif_neigh_node object which it has a reference for. But
batadv_hardif_neigh_get cannot guarantee that because it is working only
with rcu_read_lock on this list. It can therefore happen that a neigh_addr
is in this list twice or that batadv_hardif_neigh_get cannot find the
batadv_hardif_neigh_node for an neigh_addr due to some other list
operations taking place at the same time.
Instead add a batadv_hardif_neigh_node pointer directly in
batadv_neigh_node which will be used for the reference counter decremented
on release of batadv_neigh_node.
Fixes: cef63419f7 ("batman-adv: add list of unique single hop neighbors per hard-interface")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
The batadv_tt_local_entry was specific to a batadv_softif_vlan and held an
implicit reference to it. But this reference was never stored in form of a
pointer in the tt_local_entry itself. Instead batadv_tt_local_remove,
batadv_tt_local_table_free and batadv_tt_local_purge_pending_clients depend
on a consistent state of bat_priv->softif_vlan_list and that
batadv_softif_vlan_get always returns the batadv_softif_vlan object which
it has a reference for. But batadv_softif_vlan_get cannot guarantee that
because it is working only with rcu_read_lock on this list. It can
therefore happen that an vid is in this list twice or that
batadv_softif_vlan_get cannot find the batadv_softif_vlan for an vid due to
some other list operations taking place at the same time.
Instead add a batadv_softif_vlan pointer directly in batadv_tt_local_entry
which will be used for the reference counter decremented on release of
batadv_tt_local_entry.
Fixes: 35df3b298f ("batman-adv: fix TT VLAN inconsistency on VLAN re-add")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
At the moment there is no explicit reactivation of an hard-interface
upon NETDEV_UP event. In case of B.A.T.M.A.N. IV the interface is
reactivated as soon as the next OGM is scheduled for sending, but this
mechanism does not work with B.A.T.M.A.N. V. The latter does not rely
on the same scheduling mechanism as its predecessor and for this reason
the hard-interface remains deactivated forever after being brought down
once.
This patch fixes the reactivation mechanism by adding a new routing API
which explicitly allows each algorithm to perform any needed operation
upon interface re-activation.
Such API is optional and is implemented by B.A.T.M.A.N. V only and it
just takes care of setting the iface status to ACTIVE
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
In case of wireless interface retrieve the throughput by
querying cfg80211. To perform this call a separate work
must be scheduled because the function may sleep and this
is not allowed within an RCU protected context (RCU in this
case is used to iterate over all the neighbours).
Use ethtool to retrieve information about an Ethernet link
like HALF/FULL_DUPLEX and advertised bandwidth (e.g.
100/10Mbps).
The metric is updated each time a new ELP packet is sent,
this way it is possible to timely react to a metric
variation which can imply (for example) a neighbour
disconnection.
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
To enable ELP to send probing packets over wireless links
only if needed, batman-adv must keep track of the last time
it sent a unicast packet towards every neighbour.
For this purpose a 2 main changes are introduced:
1) a new member of the elp_neigh_node structure stores the
last time a unicast packet was sent towards this neighbour;
2) a wrapper function for sending unicast packets is
implemented. This function will simply update the member
describe din point 1) and then forward the packet to the
real sending routine.
Point 2) implies that any code-path leading to a unicast
sending now has to use the new wrapper.
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
This attribute is exported to user space to disable the link
throughput auto-detection by setting a fixed value.
The throughput override value is used when batman-adv is
computing the link throughput towards a neighbour.
If the value is set to 0 then batman-adv will try to detect
the throughput by itself.
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Add the support for recognising new originators in the
network and rebroadcast their OGMs.
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
This is the initial implementation of the new OGM protocol
(version 2). It has been designed to work on top of the
newly added ELP.
In the previous version the OGM protocol was used to both
measure link qualities and flood the network with the metric
information. In this version the protocol is in charge of
the latter task only, leaving the former to ELP.
This means being able to decouple the interval used by the
neighbor discovery from the OGM broadcasting, which revealed
to be costly in dense networks and needed to be relaxed so
leading to a less responsive routing protocol.
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Initially developed by Linus during a 6 months trainee study
period in Ascom (Switzerland) AG.
Signed-off-by: Linus Luessing <linus.luessing@web.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
The B.A.T.M.A.N. protocol originally only used a single
message type (called OGM) to determine the link qualities to
the direct neighbors and spreading these link quality
information through the whole mesh. This procedure is
summarized on the BATMAN concept page and explained in
details in the RFC draft published in 2008.
This approach was chosen for its simplicity during the
protocol design phase and the implementation. However, it
also bears some drawbacks:
* Wireless interfaces usually come with some packet loss,
therefore a higher broadcast rate is desirable to allow
a fast reaction on flaky connections.
Other interfaces of the same host might be connected to
Ethernet LANs / VPNs / etc which rarely exhibit packet
loss would benefit from a lower broadcast rate to reduce
overhead.
* It generally is more desirable to detect local link
quality changes at a faster rate than propagating all
these changes through the entire mesh (the far end of
the mesh does not need to care about local link quality
changes that much). Other optimizations strategies, like
reducing overhead, might be possible if OGMs weren't
used for all tasks in the mesh at the same time.
As a result detecting local link qualities shall be handled
by an independent message type, ELP, whereas the OGM message
type remains responsible for flooding the mesh with these
link quality information and determining the overall path
transmit qualities.
Developed by Linus during a 6 months trainee study period in
Ascom (Switzerland) AG.
Signed-off-by: Linus Luessing <linus.luessing@web.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
batman-adv uses a self-written reference implementation which is just based
on atomic_t. This is less obvious when reading the code than kref and
therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batman-adv uses a self-written reference implementation which is just based
on atomic_t. This is less obvious when reading the code than kref and
therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batman-adv uses a self-written reference implementation which is just based
on atomic_t. This is less obvious when reading the code than kref and
therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batman-adv uses a self-written reference implementation which is just based
on atomic_t. This is less obvious when reading the code than kref and
therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batman-adv uses a self-written reference implementation which is just based
on atomic_t. This is less obvious when reading the code than kref and
therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batman-adv uses a self-written reference implementation which is just based
on atomic_t. This is less obvious when reading the code than kref and
therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batman-adv uses a self-written reference implementation which is just based
on atomic_t. This is less obvious when reading the code than kref and
therefore increases the change that the reference counting will be missed.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
