Re: [PATCH 2/4] mm: ioremap: Add arch_ioremap/iounmap_check()

[Kefeng Wang]

On 2022/4/28 1:04, Andrew Morton wrote:
> On Wed, 27 Apr 2022 20:14:11 +0800 Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:
>
> > Add special check hook for architecture to verify addr, size
> > or prot when ioremap() or iounmap(), which will make the generic
> > ioremap more useful.
> >
> > ...
> >
> > --- a/include/asm-generic/io.h
> > +++ b/include/asm-generic/io.h
> > @@ -964,6 +964,9 @@ static inline void iounmap(volatile void __iomem *addr)
> >   #elif defined(CONFIG_GENERIC_IOREMAP)
> >   #include <linux/pgtable.h>
> >   
> > +bool arch_ioremap_check(phys_addr_t addr, size_t size, unsigned long prot);
> > +bool arch_iounmap_check(void __iomem *addr);
> Pet peeve.  The word "check" is a poor one.  I gives no sense of what
> the function is checking and it gives no sense of how the function's
> return value relates to the thing which it checks.
>
> Maybe it returns 0 on success and -EINVAL on failure.  Don't know!
>
> Don't you think that better names would be io_remap_ok(),
> io_remap_valid(), io_remap_allowed(), etc?

Will use arch_ioremap/unmap_allowed(), and I'd like to keep return bool

for now if there is no special requirements.

> Other than that,
>
> Acked-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Thanks.
> .