[PATCH v2 2/2] arm/dma-mapping: Respect NO_KERNEL_MAPPING when we don't have an IOMMU

Marek Szyprowski m.szyprowski at samsung.com
Fri Feb 6 04:16:57 PST 2015


Hello,

On 2015-02-05 11:13, Carlo Caione wrote:
> On Wed, Feb 4, 2015 at 11:21 AM, Marek Szyprowski
> <m.szyprowski at samsung.com> wrote:
>> On 2015-02-04 10:23, Carlo Caione wrote:
>>> From: "Jasper St. Pierre" <jstpierre at mecheye.net>
>>>
>>> Even without an iommu, NO_KERNEL_MAPPING is still convenient to save on
>>> kernel address space in places where we don't need a kernel mapping.
>>> Implement support for it in the two places where we're creating an
>>> expensive mapping.
>>>
>>> __alloc_from_pool uses an internal pool from which we already have
>>> virtual addresses, so it's not relevant, and __alloc_simple_buffer uses
>>> alloc_pages, which will always return a lowmem page, which is already
>>> mapped into kernel space, so we can't prevent a mapping for it in that
>>> case.
>>>
>>> Signed-off-by: Jasper St. Pierre <jstpierre at mecheye.net>
>>> Signed-off-by: Carlo Caione <carlo at caione.org>
>>> Reviewed-by: Rob Clark <robdclark at gmail.com>
>>> Reviewed-by: Daniel Drake <dsd at endlessm.com>
>>
>> Acked-by: Marek Szyprowski <m.szyprowski at samsung.com>
> Thanks. Who is supposed to take this patch? Russel?

I think this will be the best way to get it merged. Please upload it to
http://www.arm.linux.org.uk/developer/patches/

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland




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