The netlink dump functionality transfers a large number of entries from the
kernel to userspace. It is rather likely that the transfer has to
interrupted and later continued. During that time, it can happen that
either new entries are added or removed. The userspace could than either
receive some entries multiple times or miss entries.
Commit 670dc2833d ("netlink: advertise incomplete dumps") introduced a
mechanism to inform userspace about this problem. Userspace can then decide
whether it is necessary or not to retry dumping the information again.
The netlink dump functions have to be switched to exclusive locks to avoid
changes while the current message is prepared. And an external generation
sequence counter is introduced which tracks all modifications of the list.
Reported-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
A reference for the best gateway is taken when the list of gateways in the
mesh is sent via netlink. This is necessary to check whether the currently
dumped entry is the currently selected gateway or not. This information is
then transferred as flag BATADV_ATTR_FLAG_BEST.
After the comparison of the current entry is done,
batadv_v_gw_dump_entry() has to decrease the reference counter again.
Otherwise the reference will be held and thus prevents a proper shutdown of
the batman-adv interfaces (and some of the interfaces enslaved in it).
Fixes: b71bb6f924 ("batman-adv: add B.A.T.M.A.N. V bat_gw_dump implementations")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
All of the conflicts were cases of overlapping changes.
In net/core/devlink.c, we have to make care that the
resouce size_params have become a struct member rather
than a pointer to such an object.
Signed-off-by: David S. Miller <davem@davemloft.net>
The function batadv_v_gw_dump stops the processing loop when
batadv_v_gw_dump_entry returns a non-0 return code. This should only
happen when the buffer is full. Otherwise, an empty message may be
returned by batadv_gw_dump. This empty message will then stop the netlink
dumping of gateway entries. At worst, not a single entry is returned to
userspace even when plenty of possible gateways exist.
Fixes: b71bb6f924 ("batman-adv: add B.A.T.M.A.N. V bat_gw_dump implementations")
Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The header file is used by different userspace programs to inject packets
or to decode sniffed packets. It should therefore be available to them as
userspace header.
Also other components in the kernel (like the flow dissector) require
access to the packet definitions to be able to decode ETH_P_BATMAN ethernet
packets.
Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- bump version strings, by Simon Wunderlich
- de-inline hash functions to save memory footprint, by Denys Vlasenko
- Add License information to various files, by Sven Eckelmann (3 patches)
- Change batman_adv.h from ISC to MIT, by Sven Eckelmann
- Improve various includes, by Sven Eckelmann (5 patches)
- Lots of kernel-doc work by Sven Eckelmann (8 patches)
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Merge tag 'batadv-next-for-davem-20171220' of git://git.open-mesh.org/linux-merge
Simon Wunderlich says:
====================
This feature/cleanup patchset includes the following patches:
- bump version strings, by Simon Wunderlich
- de-inline hash functions to save memory footprint, by Denys Vlasenko
- Add License information to various files, by Sven Eckelmann (3 patches)
- Change batman_adv.h from ISC to MIT, by Sven Eckelmann
- Improve various includes, by Sven Eckelmann (5 patches)
- Lots of kernel-doc work by Sven Eckelmann (8 patches)
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The documentation describing kernel-doc comments for functions ("How to
format kernel-doc comments") uses parentheses at the end of the function
name. Using this format allows to use a consistent style when adding
documentation to a function and when referencing this function in a
different kernel-doc section.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The "Linux kernel licensing rules" require that each file has a SPDX
license identifier as first line (and sometimes as second line).
The FSFE REUSE practices [1] would also require the same tags but have no
restrictions on the placement in the source file. Using the "Linux kernel
licensing rules" is therefore also fulfilling the FSFE REUSE practices
requirements at the same time.
[1] https://reuse.software/practices/
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The batadv_v_gw_is_eligible function already assumes that orig_node is not
NULL. But batadv_gw_node_get may have failed to find the originator. It
must therefore be checked whether the batadv_gw_node_get failed and not
whether orig_node is NULL to detect this error.
Fixes: 50164d8f50 ("batman-adv: B.A.T.M.A.N. V - implement GW selection logic")
Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
Acked-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
The neighbor compare API implementation for B.A.T.M.A.N. V checks whether
the neigh_ifinfo for this neighbor on a specific interface exists. A
warning is printed when it isn't found.
But it is not called inside a lock which would prevent that this
information is lost right before batadv_neigh_ifinfo_get. It must therefore
be expected that batadv_v_neigh_(cmp|is_sob) might not be able to get the
requested neigh_ifinfo.
A WARN_ON for such a situation seems not to be appropriate because this
will only flood the kernel logs. The warnings must therefore be removed.
Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
checkpatch introduced with commit 63b7c73ec8 ("checkpatch: add --strict
check for ifs with unnecessary parentheses") an additional test which
identifies some unnecessary parentheses.
Remove these unnecessary parentheses to avoid the warnings and to unify the
coding style slightly more.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Two single characters (line breaks) should be put into a sequence.
Thus use the corresponding function "seq_putc".
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
- Keep fragments equally sized, avoids some problems with too small fragments,
by Sven Eckelmann
- Initialize gateway class correctly when BATMAN V is compiled in,
by Sven Eckelmann
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Merge tag 'batadv-net-for-davem-20170316' of git://git.open-mesh.org/linux-merge
Simon Wunderlich says:
====================
Here are two batman-adv bugfixes:
- Keep fragments equally sized, avoids some problems with too small fragments,
by Sven Eckelmann
- Initialize gateway class correctly when BATMAN V is compiled in,
by Sven Eckelmann
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The gateway selection class variable is shared between different algorithm
versions. But the interpretation of the content is algorithm specific. The
initialization is therefore also algorithm specific.
But this was implemented incorrectly and the initialization for BATMAN_V
always overwrote the value previously written for BATMAN_IV. This could
only be avoided when BATMAN_V was disabled during compile time.
Using a special batadv_algo hook for this initialization avoids this
problem.
Fixes: 50164d8f50 ("batman-adv: B.A.T.M.A.N. V - implement GW selection logic")
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>
Some variables are overwritten immediatelly in a functions. These don't
have to be initialized to a specific value on the stack because the value
will be overwritten before they will be used anywhere.
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>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Dump the algo V originators and neighbours.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
[sven@narfation.org: Fix includes, fix algo_ops integration]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Since the GW selection logic has been made routing protocol specific
it is now possible for B.A.T.M.A.N V to have its own mechanism by
providing the API implementation.
Implement the GW specific API in the B.A.T.M.A.N. V protocol in
order to provide a working GW selection mechanism.
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>
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 bat_algo.h had some functions declared which were not part of the
bat_algo.c file. These are instead stored in bat_v.c and bat_iv_ogm.c. The
declaration should therefore be also in bat_v.h and bat_iv_ogm,h to make
them easier to find.
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 ELP interval and throughput override interface settings are initialized
with default settings on every time an interface is added to a mesh.
This patch prevents this behavior by moving the configuration init to the
interface detection routine which runs only once per interface.
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
[a@unstable.cc: move initialization to batadv_v_hardif_init]
Signed-off-by: Antonio Quartulli <a@unstable.cc>
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>
This fix prevents nodes to wrongly create a 00:00:00:00:00:00 originator
which can potentially interfere with the rest of the neighbor statistics.
Fixes: d6f94d91f7 ("batman-adv: ELP - adding basic infrastructure")
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
When the MAC address of the primary interface is changed,
update the originator address in the ELP and OGM skb buffers as
well in order to reflect the change.
Fixes: d6f94d91f7 ("batman-adv: ELP - adding basic infrastructure")
Reported-by: Marek Lindner <marek@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
The functions batadv_neigh_ifinfo_get increase the reference counter of the
batadv_neigh_ifinfo. These have to be reduced again when the reference is
not used anymore to correctly free the objects.
Fixes: 9786906022 ("batman-adv: B.A.T.M.A.N. V - implement neighbor comparison API calls")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
batadv_neigh_ifinfo_get can return NULL when it cannot find (even when only
temporarily) anymore the neigh_ifinfo in the list neigh->ifinfo_list. This
has to be checked to avoid kernel Oopses when the ifinfo is dereferenced.
This a situation which isn't expected but is already handled by functions
like batadv_v_neigh_cmp. The same kind of warning is therefore used before
the function returns without dereferencing the pointers.
Fixes: 9786906022 ("batman-adv: B.A.T.M.A.N. V - implement neighbor comparison API calls")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
- two changes to the MAINTAINERS file where one marks our mailing list
as moderated and the other adds a missing documentation file
- kernel-doc fixes
- code refactoring and various cleanups
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Merge tag 'batman-adv-for-davem' of git://git.open-mesh.org/linux-merge
Antonio Quartulli says:
====================
pull request: batman-adv 20160504
In this pull request you have:
- two changes to the MAINTAINERS file where one marks our mailing list
as moderated and the other adds a missing documentation file
- kernel-doc fixes
- code refactoring and various cleanups
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Use a static string when showing table headers rather then
a nonsense parametric one with fixed arguments.
It is easier to grep and it does not need to be recomputed
at runtime each time.
Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
[sven@narfation.org: fix conflicts with current version]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
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>
Lists all neighbours detected by the Echo Locating Protocol
(ELP) and their throughput metric.
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>
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>
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>
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>
Sven Eckelmann