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Date:   Fri, 14 Jun 2019 16:50:01 +0200
From:   'Christoph Hellwig' <hch@lst.de>
To:     David Laight <David.Laight@ACULAB.COM>
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Subject: Re: [PATCH 16/16] dma-mapping: use exact allocation in
 dma_alloc_contiguous
Message-ID: <20190614145001.GB9088@lst.de>
References: <20190614134726.3827-1-hch@lst.de> <20190614134726.3827-17-hch@lst.de> <a90cf7ec5f1c4166b53c40e06d4d832a@AcuMS.aculab.com>
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On Fri, Jun 14, 2019 at 02:15:44PM +0000, David Laight wrote:
> Does this still guarantee that requests for 16k will not cross a 16k boundary?
> It looks like you are losing the alignment parameter.

The DMA API never gave you alignment guarantees to start with,
and you can get not naturally aligned memory from many of our
current implementations.