Message-ID: <5f556597-5f09-6baa-80bb-aef7337ae869@gmail.com>
Date:   Tue, 7 Mar 2023 12:01:47 +1300
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Subject: Re: [PATCH v3 13/34] m68k: Implement the new page table range API
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To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Matthew Wilcox <willy@infradead.org>, linux-mm@kvack.org,
        linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-m68k@lists.linux-m68k.org
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From:   Michael Schmitz <schmitzmic@gmail.com>
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Hi Geert,

On 6/03/23 20:21, Geert Uytterhoeven wrote:
>> Are we certain that contiguous vaddr always maps to contiguous paddr?
> For a general __flush_pages_to_ram() function, that would not be
> guaranteed. But as this is meant for folios, it must be true:
> https://elixir.bootlin.com/linux/latest/source/include/linux/mm_types.h#L320

Thanks for explaining - that just leaves the problem of cowboys like 
myself abusing __flush_pages_to_ram(addr, nr) with nr > 1 for something 
that isn't a folio. Maybe a comment 'nr > 1 only valid on folios' would 
help ...

Cheers,

     Michael

>
> Gr{oetje,eeting}s,
>
>                          Geert
>