Re: [PATCH v3 4/9] xen/grant-table: Allow allocating buffers suitable for DMA

[Oleksandr Andrushchenko]

On 06/13/2018 04:12 AM, Boris Ostrovsky wrote:
> On 06/12/2018 09:41 AM, Oleksandr Andrushchenko wrote:
> > From: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
> >
> > Extend grant table module API to allow allocating buffers that can
> > be used for DMA operations and mapping foreign grant references
> > on top of those.
> > The resulting buffer is similar to the one allocated by the balloon
> > driver in terms that proper memory reservation is made
> > ({increase|decrease}_reservation and VA mappings updated if needed).
> > This is useful for sharing foreign buffers with HW drivers which
> > cannot work with scattered buffers provided by the balloon driver,
> > but require DMAable memory instead.
> >
> > Signed-off-by: Oleksandr Andrushchenko 
> > <oleksandr_andrushchenko@xxxxxxxx>
>
> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
>
> with a small nit below
>
>
> > ---
> > Â drivers/xen/KconfigÂÂÂÂÂÂ | 13 ++++++
> > Â drivers/xen/grant-table.c | 97 +++++++++++++++++++++++++++++++++++++++
> > Â include/xen/grant_table.h | 18 ++++++++
> > Â 3 files changed, 128 insertions(+)
> >
> > diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
> > index e5d0c28372ea..39536ddfbce4 100644
> > --- a/drivers/xen/Kconfig
> > +++ b/drivers/xen/Kconfig
> > @@ -161,6 +161,19 @@ config XEN_GRANT_DEV_ALLOC
> > ÂÂÂÂÂÂÂ to other domains. This can be used to implement frontend drivers
> > ÂÂÂÂÂÂÂ or as part of an inter-domain shared memory channel.
> > Â +config XEN_GRANT_DMA_ALLOC
> > +ÂÂÂ bool "Allow allocating DMA capable buffers with grant reference 
> > module"
> > +ÂÂÂ depends on XEN && HAS_DMA
> > +ÂÂÂ help
> > +ÂÂÂÂÂ Extends grant table module API to allow allocating DMA capable
> > +ÂÂÂÂÂ buffers and mapping foreign grant references on top of it.
> > +ÂÂÂÂÂ The resulting buffer is similar to one allocated by the balloon
> > +ÂÂÂÂÂ driver in terms that proper memory reservation is made
> > +ÂÂÂÂÂ ({increase|decrease}_reservation and VA mappings updated if 
> > needed).
>
> I think you should drop the word "terms" and say "is made *by*" and 
> "VA mappings *are* updated"
>
> And similar change in the commit message.
Will, change, thank you
> -boris