[libvirt] [PATCH v2 1/4] virInterface: Expose link state & speed

[Michal Privoznik]

On 11.06.2014 03:13, John Ferlan wrote:
>
>
> On 06/05/2014 11:39 AM, Michal Privoznik wrote:
>> Currently it is not possible to determine the speed of an interface
>> and whether a link is actually detected from the API. Orchestrating
>> platforms want to be able to determine when the link has failed and
>> where multiple speeds may be available which one the interface is
>> actually connected at. This commit introduces an extension to our
>> interface XML (without implementation to interface driver backends):
>>
>>    <interface type='ethernet' name='eth0'>
>>      <start mode='none'/>
>>      <mac address='aa:bb:cc:dd:ee:ff'/>
>>      <link speed='1000' state='up'/>
>>      <mtu size='1492'/>
>>      ...
>>    </interface>
>>
>> Where @speed is negotiated link speed in Mbits per second, and state
>> is the current NIC state (can be one of the following:  "unknown",
>> "notpresent", "down", "lowerlayerdown","testing", "dormant", "up").
>>
>> Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
>> ---
>>   docs/schemas/basictypes.rng                     | 25 ++++++++++
>>   docs/schemas/interface.rng                      |  1 +
>>   src/conf/device_conf.c                          | 62 +++++++++++++++++++++++++
>>   src/conf/device_conf.h                          | 27 ++++++++++-
>>   src/conf/interface_conf.c                       | 11 ++++-
>>   src/conf/interface_conf.h                       |  2 +
>>   src/libvirt_private.syms                        |  4 ++
>>   tests/interfaceschemadata/bridge-no-address.xml |  1 +
>>   tests/interfaceschemadata/bridge.xml            |  1 +
>>   tests/interfaceschemadata/ethernet-dhcp.xml     |  1 +
>>   10 files changed, 133 insertions(+), 2 deletions(-)
>>
>
> Already been ACK'd, but I will point out the interface.html.in hasn't
> been updated - later you update the nodedev.html.in file - so probably
> reasonable to do so again. While at it the consistency of using "Mbits"
> vs. "Mb" in the comment in device_conf.h

The first issue has simple explanation - there's no interface.html.in 
yet. Yes we lack the virInterface XML documentation. The second one I'm 
fixing prior to push.

>
> Just so I understand - the reality is regardless of what the XML is on
> input - the code will still check/get/set the link state/speed - so this
> is mostly an output thing.

Yes. So far this is only for getting the link speed & state. Which 
brings up an interesting question. With recent issue with QoS on 
bridgeless networks on mind - should we make virInterface XML parsing 
actually reject any <link/> since it's output element only? One could 
argue that we usually ignore unknown elements, but then <link/> is not 
unknown element anymore. One way or another, it can be done in a 
separate patch.

>
> It's not like if on input someone had "down" for the state that we'd
> attempt to set the link down...  or if the speed on input was 500, but
> the file had 1000 - there's no changing of the file.
>
> John
>

Michal