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Date: Thu, 21 Apr 2011 12:06:00 +0200
From: Daniel =?iso-8859-1?Q?Gl=F6ckner?= <daniel-gl@gmx.net>
To: Bob Liu <lliubbo@gmail.com>
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Subject: Re: [PATCH v3] media:uvc_driver: add uvc support on no-mmu arch
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On Thu, Apr 21, 2011 at 05:57:31PM +0800, Bob Liu wrote:
> On Thu, Apr 21, 2011 at 5:47 PM, Daniel Glöckner <daniel-gl@gmx.net> wrote:
> > On Thu, Apr 21, 2011 at 04:20:36PM +0800, Bob Liu wrote:
> >> > on mmu systems do_mmap_pgoff contains a len = PAGE_ALIGN(len); line.
> >> > If we depend on this behavior, why not do it here as well and get rid
> >> > of the #ifdef?
> >> >
> >>
> >> If do it in do_mmap_pgoff() the whole system will be effected, I am
> >> not sure whether
> >> it's correct and needed for other subsystem.
> >
> > With "here" I was referring to uvc_queue_mmap.
> >
> 
> I am sorry, I didn't get your idea. You mean using  PAGE_ALIGN() here for both
> mmu and no-mmu arch ?

Yes, rounding size to pages also increases the chance of the following
while loop to end, should mmu do_mmap_pgoff ever have that line removed.

  Daniel