Re: [HMM 12/15] mm/migrate: new memory migration helper for use with device memory v4

[Jerome Glisse]

On Tue, Jul 25, 2017 at 03:45:14PM -0700, Evgeny Baskakov wrote:
> On 7/20/17 6:33 PM, Jerome Glisse wrote:
> 
> > So i pushed an updated hmm-next branch it should have all fixes so far, including
> > something that should fix this issue. I still want to go over all emails again
> > to make sure i am not forgetting anything.
> > 
> > Cheers,
> > Jérôme
> 
> Hi Jerome,
> 
> Thanks for updating the documentation for hmm_devmem_ops.
> 
> I have an inquiry about the "fault" callback, though. The documentation says
> "Returns: 0 on success", but can the driver set any VM_FAULT_* flags? For
> instance, the driver might want to set the VM_FAULT_MAJOR flag to indicate
> that a heavy-weight page migration has happened on the page fault.
> 
> If that is possible, can you please update the documentation and list the
> flags that are permitted in the callback's return value?

Yes you can.

Jérôme