On Tue 19 May, 2020, 1:47 AM Matthew Wilcox, <willy@xxxxxxxxxxxxx> wrote:
>
> On Tue, May 19, 2020 at 01:28:23AM +0530, Souptick Joarder wrote:
> > The idea is to get rid of write parameter. Instead caller will pass
> > FOLL_WRITE to __get_user_pages_fast(). This will not change any
> > functionality of the API. Once it is upstream all the callers will
> > be changed to pass FOLL_WRITE.
>
> Uhh ... until you change all the callers, haven't you just broken all
> the callers?
All the callers have called the API with either 1 or 0. I think, it's
not going to break
any of the callers.
>
> > -int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
> > - struct page **pages)
> > +int __get_user_pages_fast(unsigned long start, int nr_pages,
> > + unsigned int gup_flags, struct page **pages)
> > {
> > unsigned long len, end;
> > unsigned long flags;
> > @@ -2685,10 +2692,7 @@ int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
> > * Internally (within mm/gup.c), gup fast variants must set FOLL_GET,
> > * because gup fast is always a "pin with a +1 page refcount" request.
> > */
> > - unsigned int gup_flags = FOLL_GET;
> > -
> > - if (write)
> > - gup_flags |= FOLL_WRITE;
> > + gup_flags |= FOLL_GET;
