linux-kernel - Re: [PATCHv2 1/3] arm64: Drop alloc function from create

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Message-ID: <20160201121111.GE674@leverpostej>
Date:	Mon, 1 Feb 2016 12:11:12 +0000
From:	Mark Rutland <mark.rutland@....com>
To:	Ard Biesheuvel <ard.biesheuvel@...aro.org>
Cc:	Laura Abbott <labbott@...oraproject.org>,
	Catalin Marinas <catalin.marinas@....com>,
	Will Deacon <will.deacon@....com>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCHv2 1/3] arm64: Drop alloc function from create_mapping

On Sat, Jan 30, 2016 at 11:34:50AM +0100, Ard Biesheuvel wrote:
> On 30 January 2016 at 00:46, Laura Abbott <labbott@...oraproject.org> wrote:
> >
> > create_mapping is only used in fixmap_remap_fdt. All the create_mapping
> > calls need to happen on existing translation table pages without
> > additional allocations. Rather than have an alloc function be called
> > and fail, just set it to NULL and catch it's use. Also change
> 
> s/it's/its/
> 
> > the name to create_mapping_noalloc to better capture what exactly is
> > going on.
> >
> > Signed-off-by: Laura Abbott <labbott@...oraproject.org>
> 
> With one nit below:
> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@...aro.org>

[...]

> > +/*
> > + * This function is for mapping using existing sections only.
> 
> Could you improve this comment? 'existing sections' does not quite
> cover what we expect to deal with imo
> > + */
> > +static void __init create_mapping_noalloc(phys_addr_t phys, unsigned long virt,
> >                                   phys_addr_t size, pgprot_t prot)

Perhaps:

/*
 * This function can only be used to modify existing table entries,
 * without allocating new levels of table. Note that this permits the
 * creation of new section or page entries.
 */

Either way:

Reviewed-by: Mark Rutland <mark.rutland@....com>

Thanks for putting this together!

Mark.