[PATCH v2] fs/dax: include <asm/page.h> to fix build error on ARC

[Matthew Wilcox]

On Mon, Jan 04, 2021 at 12:13:02PM -0800, Dan Williams wrote:
> On Thu, Dec 31, 2020 at 8:29 PM Randy Dunlap <rdunlap at infradead.org> wrote:
> > +++ lnx-511-rc1/fs/dax.c
> > @@ -25,6 +25,7 @@
> >  #include <linux/sizes.h>
> >  #include <linux/mmu_notifier.h>
> >  #include <linux/iomap.h>
> > +#include <asm/page.h>
> 
> I would expect this to come from one of the linux/ includes like
> linux/mm.h. asm/ headers are implementation linux/ headers are api.

It does indeed come from linux/mm.h already.  And a number of
other random places, including linux/serial.h.  Our headers are a mess,
but they shouldn't be made worse by adding _this_ include.  So I
second Dan's objection here.

> Once you drop that then the subject of this patch can just be "arc:
> add a copy_user_page() implementation", and handled by the arc
> maintainer (or I can take it with Vineet's ack).
> 
> >  #include <asm/pgalloc.h>
> 
> Yes, this one should have a linux/ api header to front it, but that's
> a cleanup for another day.

Definitely more involved.