On Wed, Aug 28, 2013 at 11:26:31AM +1000, Benjamin Herrenschmidt wrote:

On Wed, 2013-08-28 at 10:51 +1000, Alexey Kardashevskiy wrote:

quoted

The ioctl I made up is basically a copy of KVM_CREATE_SPAPR_TCE which does
the same thing for emulated devices and it is there for quite a while but
it is not really extensible. And these two ioctls share some bits of code.
Now we will have 2 pieces of code which do almost the same thing but in a
different way. Kinda sucks :(

Right. Thus the question, Gleb, we can either:

 - Keep Alexey patch as-is allowing us to *finally* merge that stuff
that's been around for monthes

 - Convert *both* existing TCE objects to the new 
KVM_CREATE_DEVICE, and have some backward compat code for the old one.

I don't think it makes sense to have the "emulated TCE" and "IOMMU TCE"
objects use a fundamentally different API and infrastructure.

As a general rule we are not going to mandate converting old devices to
new API, but if it make sense to do here I would much prefer that over
adding another special ioctl

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So my stuff is not going to upstream again. Heh. Ok. I'll implement it.

Thanks! Should I keep KVM_CAP_SPAPR_MULTITCE capability patch or can I
drop it for now?

Please keep it, it is unrelated to the IOMMU-VFIO thing.

--
			Gleb.