Re: [PATCH v2] um: add dummy ioremap and iounmap functions

From: Geert Uytterhoeven
Date: Sat May 27 2017 - 14:08:38 EST


Hi Logan,

On Thu, May 25, 2017 at 5:53 PM, Logan Gunthorpe <logang@xxxxxxxxxxxx> wrote:
> On 25/05/17 09:48 AM, Richard Weinberger wrote:
>> Which ones are failing?
>> I thought we killed the problem by making CONFIG_COMPILE_TEST depend on !UML.
>
> None, at the moment. My work is trying to add iomem support to scatter
> lists and thus I want to call ioremap in scatterlist.c. That's when
> things fail to build. We could put an '#ifdef HAS_IOMEM' around only the
> uses, but I thought this approach was cleaner. However, if people would
> rather I do that, let me know and I will.
>
>> I was never a fan of that approach because in my opinion drivers should have
>> proper dependencies, including a dependency on HAS_IOMEM.
>
> This doesn't really work when we try to use it in a core library which
> can't depend on HAS_IOMEM.

Still, those code patch could be protected by #ifdef CONFIG_HAS_IOMEM,
or better, if (IS_ENABLED(CONFIG_HAS_IOMEM)).

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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