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Date:   Fri, 15 Jul 2022 12:31:37 +0300
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Subject: Re: [PATCH v1 1/6] dma-buf: Add _unlocked postfix to function names
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        Tomeu Vizoso <tomeu.vizoso@collabora.com>,
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        Rob Clark <robdclark@gmail.com>,
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        Marek Szyprowski <m.szyprowski@samsung.com>,
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Cc:     dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        Dmitry Osipenko <digetx@gmail.com>,
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 <43c06f53-bad8-af99-0b57-781dbf716768@amd.com>
From:   Dmitry Osipenko <dmitry.osipenko@collabora.com>
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On 7/15/22 10:19, Christian König wrote:
>> -struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment
>> *attach,
>> -                    enum dma_data_direction direction)
>> +struct sg_table *
>> +dma_buf_map_attachment_unlocked(struct dma_buf_attachment *attach,
>> +                enum dma_data_direction direction)
> 
> The locking state of mapping and unmapping operations depend on if the
> attachment is dynamic or not.
> 
> So this here is not a good idea at all since it suggests that the
> function is always called without holding the lock.

I had the same thought while was working on this patch and initially was
thinking about adding an "unlocked" alias to dma_buf_map_attachment().
In the end I decided that it will create even more confusion and it's
simpler just to rename this func here since there are only two drivers
using the dynamic mapping.

Do you have suggestions how to improve it?

-- 
Best regards,
Dmitry