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Date: Mon, 17 Oct 2011 11:39:19 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
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Subject: Re: [PATCH 2/9] mm: alloc_contig_freed_pages() added
Message-Id: <20111017113919.3b7ac253.akpm@linux-foundation.org>
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On Mon, 17 Oct 2011 14:21:07 +0200
Marek Szyprowski <m.szyprowski@samsung.com> wrote:

> > > +
> > > +void free_contig_pages(unsigned long pfn, unsigned nr_pages)
> > > +{
> > > +	struct page *page = pfn_to_page(pfn);
> > > +
> > > +	while (nr_pages--) {
> > > +		__free_page(page);
> > > +		++pfn;
> > > +		if (likely(zone_pfn_same_memmap(pfn - 1, pfn)))
> > > +			++page;
> > > +		else
> > > +			page = pfn_to_page(pfn);
> > > +	}
> > > +}
> > 
> > You're sure these functions don't need EXPORT_SYMBOL()?  Maybe the
> > design is that only DMA core calls into here (if so, that's good).
> 
> Drivers should not call it, it is intended to be used by low-level DMA
> code.

OK, thanks for checking.

> Do you think that a comment about missing EXPORT_SYMBOL is 
> required?

No.  If someone later wants to use these from a module then we can look
at their reasons and make a decision at that time.