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Date:   Thu, 3 Sep 2020 18:12:52 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     Nicolin Chen <nicoleotsuka@gmail.com>,
        Christoph Hellwig <hch@lst.de>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
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Subject: Re: [PATCH 1/2] dma-mapping: introduce
 dma_get_seg_boundary_nr_pages()
Message-ID: <20200903161252.GA24841@lst.de>
References: <20200901221646.26491-1-nicoleotsuka@gmail.com> <20200901221646.26491-2-nicoleotsuka@gmail.com> <CAHp75VcVJBSnPQ6NfdF8FdEDfM+oQ=Sr+cH5VGX4SrAqrgpf-g@mail.gmail.com>
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On Thu, Sep 03, 2020 at 01:57:39PM +0300, Andy Shevchenko wrote:
> > +{
> > +       if (!dev)
> > +               return (U32_MAX >> page_shift) + 1;
> > +       return (dma_get_seg_boundary(dev) >> page_shift) + 1;
> 
> Can it be better to do something like
>   unsigned long boundary = dev ? dma_get_seg_boundary(dev) : U32_MAX;
> 
>   return (boundary >> page_shift) + 1;
> 
> ?

I don't really see what that would buy us.