Messages in this thread | | | Date | Tue, 24 May 2022 22:32:34 +0800 | Subject | Re: [PATCH v3 4/6] mm: ioremap: Add arch_ioremap/iounmap() | From | Kefeng Wang <> |
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On 2022/5/24 20:37, Arnd Bergmann wrote: > On Thu, May 19, 2022 at 10:25 AM Kefeng Wang <wangkefeng.wang@huawei.com> wrote: >> Add special hook for architecture to verify or setup addr, size >> or prot when ioremap() or iounmap(), which will make the generic >> ioremap more useful. >> >> arch_ioremap() return a pointer, >> - IS_ERR means return an error >> - NULL means continue to remap >> - a non-NULL, non-IS_ERR pointer is directly returned >> arch_iounmap() return a int value, >> - 0 means continue to vunmap >> - error code means skip vunmap and return directly >> >> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> > I don't really like interfaces that mix error pointers and NULL pointer > returns. > > Would it be possible to have a special error code other than NULL > for the fallback case? I don't find a good error code, maybe ENOTSUPP, any better suggestion? > > arnd > > .
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