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Date:   Fri, 31 Mar 2023 14:48:34 +0200
From:   "Arnd Bergmann" <arnd@arndb.de>
To:     "Linus Walleij" <linus.walleij@linaro.org>,
        "Arnd Bergmann" <arnd@kernel.org>
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Subject: Re: [PATCH 17/21] ARM: dma-mapping: use arch_sync_dma_for_{device,cpu}()
 internally
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On Fri, Mar 31, 2023, at 11:10, Linus Walleij wrote:
> On Mon, Mar 27, 2023 at 2:16=E2=80=AFPM Arnd Bergmann <arnd@kernel.org=
> wrote:
>
>> From: Arnd Bergmann <arnd@arndb.de>
>>
>> The arm specific iommu code in dma-mapping.c uses the page+offset bas=
ed
>> __dma_page_cpu_to_dev()/__dma_page_dev_to_cpu() helpers in place of t=
he
>> phys_addr_t based arch_sync_dma_for_device()/arch_sync_dma_for_cpu()
>> wrappers around the.
>
> Broken sentence?

I've changed s/the/them/ now, at least I think that's what I meant to
write in the first place.

>> In order to be able to move the latter part set of functions into
>> common code, change the iommu implementation to use them directly
>> and remove the internal ones as a separate interface.
>>
>> As page+offset and phys_address are equivalent, but are used in
>> different parts of the code here, this allows removing some of
>> the conversion but adds them elsewhere.
>>
>> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
>
> Looks good to me, took me some time to verify and understand
> the open-coded version of PFN_UP() and this refactoring alone
> makes the patch highly valuable.
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Thanks!

    ARnd