Re: [PATCH v2] fpga: dfl: afu: convert get_user_pages() --> pin_user_pages()

[John Hubbard]

On 2020-05-23 13:57, Moritz Fischer wrote:
> On Fri, May 22, 2020 at 06:52:34PM -0700, John Hubbard wrote:
> > On 2020-05-19 13:14, John Hubbard wrote:
> > > This code was using get_user_pages_fast(), in a "Case 2" scenario
> > > (DMA/RDMA), using the categorization from [1]. That means that it's
> > > time to convert the get_user_pages_fast() + put_page() calls to
> > > pin_user_pages_fast() + unpin_user_pages() calls.
> > >
> > > There is some helpful background in [2]: basically, this is a small
> > > part of fixing a long-standing disconnect between pinning pages, and
> > > file systems' use of those pages.
> > >
> > > [1] Documentation/core-api/pin_user_pages.rst
> > >
> > > [2] "Explicit pinning of user-space pages":
> > >       https://lwn.net/Articles/807108/
> > >
> > > Cc: Xu Yilun <yilun.xu@xxxxxxxxx>
> > > Cc: Wu Hao <hao.wu@xxxxxxxxx>
> > > Cc: Moritz Fischer <mdf@xxxxxxxxxx>
> > > Cc: linux-fpga@xxxxxxxxxxxxxxx
> > > Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
> >
> >
> > Hi Moritz and FPGA developers,
> >
> > Is this OK? And if so, is it going into your git tree? Or should I
> > send it up through a different tree? (I'm new to the FPGA development
> > model).
>
> I can take it, sorry for sluggish response.

That's great news, thanks Moritz! Sorry to be pushy, just didn't want it
to get lost. :)

thanks,
--
John Hubbard
NVIDIA