Re: [PATCH] media: omap3isp: Shuffle cacheflush.h and include mm.h

2020-05-27 Thread Laurent Pinchart
Hi Nathan,

(CC'ing Sakari Ailus and the linux-media mailing list)

On Wed, May 27, 2020 at 01:13:37AM -0700, Nathan Chancellor wrote:
> On Wed, May 27, 2020 at 09:02:51AM +0200, Geert Uytterhoeven wrote:
> > On Wed, May 27, 2020 at 6:37 AM Nathan Chancellor wrote:
> > > After mm.h was removed from the asm-generic version of cacheflush.h,
> > > s390 allyesconfig shows several warnings of the following nature:
> > >
> > > In file included from ./arch/s390/include/generated/asm/cacheflush.h:1,
> > >  from drivers/media/platform/omap3isp/isp.c:42:
> > > ./include/asm-generic/cacheflush.h:16:42: warning: 'struct mm_struct'
> > > declared inside parameter list will not be visible outside of this
> > > definition or declaration
> > >
> > > cacheflush.h does not include mm.h nor does it include any forward
> > > declaration of these structures hence the warning. To avoid this,
> > > include mm.h explicitly in this file and shuffle cacheflush.h below it.
> > >
> > > Fixes: 19c0054597a0 ("asm-generic: don't include  in 
> > > cacheflush.h")
> > > Signed-off-by: Nathan Chancellor 
> > 
> > Thanks for your patch!
> > 
> > > I am aware the fixes tag is kind of irrelevant because that SHA will
> > > change in the next linux-next revision and this will probably get folded
> > > into the original patch anyways but still.
> > >
> > > The other solution would be to add forward declarations of these structs
> > > to the top of cacheflush.h, I just chose to do what Christoph did in the
> > > original patch. I am happy to do that instead if you all feel that is
> > > better.
> > 
> > That actually looks like a better solution to me, as it would address the
> > problem for all users.

Headers should be self-contained, so that would be the best fix in my
opinion.

This being said, as cacheflush.h isn't needed in isp.c, I think we
should also drop it. It seems to have been included there since the
first driver version, and was likely a left-over from the out-of-tree
development. Manual cache handling was part of
drivers/media/platform/omap3isp/ispqueue.c and has been removed in
commit fbac1400bd1a ("[media] omap3isp: Move to videobuf2").

cacheflush.h can also be dropped from ispvideo.c which suffers from the
same issue.

> > >  drivers/media/platform/omap3isp/isp.c | 5 +++--
> > >  1 file changed, 3 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/media/platform/omap3isp/isp.c 
> > > b/drivers/media/platform/omap3isp/isp.c
> > > index a4ee6b86663e..54106a768e54 100644
> > > --- a/drivers/media/platform/omap3isp/isp.c
> > > +++ b/drivers/media/platform/omap3isp/isp.c
> > > @@ -39,8 +39,6 @@
> > >   * Troy Laramy 
> > >   */
> > >
> > > -#include 
> > > -
> > >  #include 
> > >  #include 
> > >  #include 
> > > @@ -49,6 +47,7 @@
> > >  #include 
> > >  #include 
> > >  #include 
> > > +#include 
> > >  #include 
> > >  #include 
> > >  #include 
> > > @@ -58,6 +57,8 @@
> > >  #include 
> > >  #include 
> > >
> > > +#include 
> > > +
> > >  #ifdef CONFIG_ARM_DMA_USE_IOMMU
> > >  #include 
> > >  #endif
> > 
> > Why does this file need  at all?
> > It doesn't call any of the flush_*() functions, and seems to compile fine
> > without (on arm32).
> > 
> > Perhaps it was included at the top intentionally, to override the 
> > definitions
> > of copy_{to,from}_user_page()? Fortunately that doesn't seem to be the
> > case, from a quick look at the assembler output.
> > 
> > So let's just remove the #include instead?
> 
> Sounds good to me. I can send a patch if needed or I suppose Andrew can
> just make a small fixup patch for it. Let me know what I should do.

-- 
Regards,

Laurent Pinchart


Re: [PATCH] media: omap3isp: Shuffle cacheflush.h and include mm.h

2020-05-27 Thread Nathan Chancellor
Hi Geert,

On Wed, May 27, 2020 at 09:02:51AM +0200, Geert Uytterhoeven wrote:
> Hi Nathan,
> 
> CC Laurent
> 
> On Wed, May 27, 2020 at 6:37 AM Nathan Chancellor
>  wrote:
> > After mm.h was removed from the asm-generic version of cacheflush.h,
> > s390 allyesconfig shows several warnings of the following nature:
> >
> > In file included from ./arch/s390/include/generated/asm/cacheflush.h:1,
> >  from drivers/media/platform/omap3isp/isp.c:42:
> > ./include/asm-generic/cacheflush.h:16:42: warning: 'struct mm_struct'
> > declared inside parameter list will not be visible outside of this
> > definition or declaration
> >
> > cacheflush.h does not include mm.h nor does it include any forward
> > declaration of these structures hence the warning. To avoid this,
> > include mm.h explicitly in this file and shuffle cacheflush.h below it.
> >
> > Fixes: 19c0054597a0 ("asm-generic: don't include  in 
> > cacheflush.h")
> > Signed-off-by: Nathan Chancellor 
> 
> Thanks for your patch!
> 
> > I am aware the fixes tag is kind of irrelevant because that SHA will
> > change in the next linux-next revision and this will probably get folded
> > into the original patch anyways but still.
> >
> > The other solution would be to add forward declarations of these structs
> > to the top of cacheflush.h, I just chose to do what Christoph did in the
> > original patch. I am happy to do that instead if you all feel that is
> > better.
> 
> That actually looks like a better solution to me, as it would address the
> problem for all users.
> 
> >  drivers/media/platform/omap3isp/isp.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/media/platform/omap3isp/isp.c 
> > b/drivers/media/platform/omap3isp/isp.c
> > index a4ee6b86663e..54106a768e54 100644
> > --- a/drivers/media/platform/omap3isp/isp.c
> > +++ b/drivers/media/platform/omap3isp/isp.c
> > @@ -39,8 +39,6 @@
> >   * Troy Laramy 
> >   */
> >
> > -#include 
> > -
> >  #include 
> >  #include 
> >  #include 
> > @@ -49,6 +47,7 @@
> >  #include 
> >  #include 
> >  #include 
> > +#include 
> >  #include 
> >  #include 
> >  #include 
> > @@ -58,6 +57,8 @@
> >  #include 
> >  #include 
> >
> > +#include 
> > +
> >  #ifdef CONFIG_ARM_DMA_USE_IOMMU
> >  #include 
> >  #endif
> 
> Why does this file need  at all?
> It doesn't call any of the flush_*() functions, and seems to compile fine
> without (on arm32).
> 
> Perhaps it was included at the top intentionally, to override the definitions
> of copy_{to,from}_user_page()? Fortunately that doesn't seem to be the
> case, from a quick look at the assembler output.
> 
> So let's just remove the #include instead?

Sounds good to me. I can send a patch if needed or I suppose Andrew can
just make a small fixup patch for it. Let me know what I should do.

Cheers,
Nathan


Re: [PATCH] media: omap3isp: Shuffle cacheflush.h and include mm.h

2020-05-27 Thread Geert Uytterhoeven
Hi Nathan,

CC Laurent

On Wed, May 27, 2020 at 6:37 AM Nathan Chancellor
 wrote:
> After mm.h was removed from the asm-generic version of cacheflush.h,
> s390 allyesconfig shows several warnings of the following nature:
>
> In file included from ./arch/s390/include/generated/asm/cacheflush.h:1,
>  from drivers/media/platform/omap3isp/isp.c:42:
> ./include/asm-generic/cacheflush.h:16:42: warning: 'struct mm_struct'
> declared inside parameter list will not be visible outside of this
> definition or declaration
>
> cacheflush.h does not include mm.h nor does it include any forward
> declaration of these structures hence the warning. To avoid this,
> include mm.h explicitly in this file and shuffle cacheflush.h below it.
>
> Fixes: 19c0054597a0 ("asm-generic: don't include  in 
> cacheflush.h")
> Signed-off-by: Nathan Chancellor 

Thanks for your patch!

> I am aware the fixes tag is kind of irrelevant because that SHA will
> change in the next linux-next revision and this will probably get folded
> into the original patch anyways but still.
>
> The other solution would be to add forward declarations of these structs
> to the top of cacheflush.h, I just chose to do what Christoph did in the
> original patch. I am happy to do that instead if you all feel that is
> better.

That actually looks like a better solution to me, as it would address the
problem for all users.

>  drivers/media/platform/omap3isp/isp.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/platform/omap3isp/isp.c 
> b/drivers/media/platform/omap3isp/isp.c
> index a4ee6b86663e..54106a768e54 100644
> --- a/drivers/media/platform/omap3isp/isp.c
> +++ b/drivers/media/platform/omap3isp/isp.c
> @@ -39,8 +39,6 @@
>   * Troy Laramy 
>   */
>
> -#include 
> -
>  #include 
>  #include 
>  #include 
> @@ -49,6 +47,7 @@
>  #include 
>  #include 
>  #include 
> +#include 
>  #include 
>  #include 
>  #include 
> @@ -58,6 +57,8 @@
>  #include 
>  #include 
>
> +#include 
> +
>  #ifdef CONFIG_ARM_DMA_USE_IOMMU
>  #include 
>  #endif

Why does this file need  at all?
It doesn't call any of the flush_*() functions, and seems to compile fine
without (on arm32).

Perhaps it was included at the top intentionally, to override the definitions
of copy_{to,from}_user_page()? Fortunately that doesn't seem to be the
case, from a quick look at the assembler output.

So let's just remove the #include instead?

Gr{oetje,eeting}s,

Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds


Re: [PATCH] media: omap3isp: Shuffle cacheflush.h and include mm.h

2020-05-26 Thread Christoph Hellwig
On Tue, May 26, 2020 at 09:34:27PM -0700, Nathan Chancellor wrote:
> After mm.h was removed from the asm-generic version of cacheflush.h,
> s390 allyesconfig shows several warnings of the following nature:

Hmm, I'm pretty sure I sent the same fix a few days ago in response to
a build bot report.  But if that didn't get picked up I'm fine with
your version of it as well of course:

Acked-by: Christoph Hellwig