[libvirt] summary of current vfio mdev upstreaming status

[Jike Song]

On 09/29/2016 06:58 PM, Kirti Wankhede wrote:
> 
> 
> On 9/29/2016 2:47 PM, Neo Jia wrote:
>> On Thu, Sep 29, 2016 at 04:55:39PM +0800, Jike Song wrote:
>>> Hi all,
>>>
>>> In order to have a clear understanding about the VFIO mdev upstreaming
>>> status, I'd like to summarize it. Please share your opinions on this,
>>> and correct my misunderstandings.
>>>
>>> The whole vfio mdev series can be logically divided into several parts,
>>> they work together to provide the mdev support.
>>
> 
> Thanks Jike for summarizing. We already have separate patch for each of
> these logical parts. I had maintained patch sequence in incremental
> depending order.
> 
>> Hi Jike,
>>
>> Thanks for summarizing this, but I will defer to Kirti to comment on the actual
>> upstream status of her patches, couples things to note though:
>>
>> 1) iommu type1 patches have been extensively reviewed by Alex already and we
>> have one action item left to implement which is already queued up in v8 patchset.
>>
> 
> That's right Neo.
> 

I'm talking about v7. Sure before that Alex gave full reviews..

>> 2) regarding the sysfs interface and libvirt discussion, I would like to hear
>> what kind of attributes Intel folks are having so far as Daniel is
>> asking about adding a class "gpu" which will pull several attributes as mandatory.
>>

As Kevin said, no. 

>> Thanks,
>> Neo
>>
>>>
>>>
>>>
>>> PART 1: mdev core driver
>>>
>>> 	[task]
>>> 		-	the mdev bus/device support
>>> 		-	the utilities of mdev lifecycle management
>>> 		-	the physical device register/unregister interfaces
>>>
>>> 	[status]
>>> 		-	basically agreed by community
>>>
>>>
>>> PART 2: vfio bus driver for mdev
>>>
>>> 	[task]
>>> 		-	interfaces with vendor drivers
>>> 		-	the vfio bus implementation
>>>
>>> 	[status]
>>>
>>> 		-	basically agreed by community
>>>
> 
> I'm working on v8 version for above patches based on previous discussions.
> 
>>>
>>> PART 3: iommu support for mdev
>>>
>>> 	[task]
>>> 		-	iommu support for mdev
>>>
>>> 	[status]
>>> 		-	Kirti's v7 implementation, not yet fully reviewed
>>>
>>>
>>> PART 4: sysfs interfaces for mdev
>>>
>>> 	[task]
>>> 		-	define the hierarchy of minimal sysfs directories/files
>>> 		-	check the validity from vendor drivers, init/de-init them
>>> 	[status]
>>> 		-	interfaces are in discussion
>>>
>>>
> 
> From coding perspective, this is part of mdev core module. I think we
> can't completely separate this part from mdev core module while coding
> it. Yes, this interface is still in discussion and we need to settle
> down on that soon.
> 

I Still think it's possible to separate them, but hey, looking forward to
your implementation :)

>>> PART 6: Documentation
>>>
>>> 	[task]
>>> 		-	clearly document the architecture and interfaces
>>> 		-	coding example for vendor drivers
>>>
>>> 	[status]
>>> 		-	N/A
>>>
> 
> I had tried to maintain the document as per changes going on in above
> patches from v6 onward and will continue to update it for each version
> accordingly.
> 
> I had sent out patch with sample driver few hours back wrt v7 patchset.
> And henceforth I'll keep on updating sample driver as per changes in
> mdev modules and add it in my patch series.

Good to know that.

> 
> Thanks,
> Kirti
> 
--
Thanks,
Jike