[PATCH for-4.13] nvme-pci: use dma memory for the host memory buffer descriptors

[Johannes Thumshirn]

On Mon, Aug 28, 2017 at 10:47:18AM +0200, Christoph Hellwig wrote:
> -	descs = kcalloc(max_entries, sizeof(*descs), GFP_KERNEL);
> +	descs = dma_zalloc_coherent(dev->dev, max_entries * sizeof(*descs),
> +			&descs_dma, GFP_KERNEL);

[...]

> -	kfree(descs);
> +	dma_free_coherent(dev->dev, max_entries * sizeof(*dev->host_mem_descs),
> +			descs, descs_dma);

If the patch isn't super urgent, I'd prefere the sizeof() arguments being
aligned, i.e. either sizeof(*descs) _or_ sizeof(*dev->host_mem_descs) but not
both. It's rather confusing for the reader. Maybe just cache the max_entries *
sizeof(*dev->host_mem_descs) value?

Other than that it looks good to me,
Reviewed-by: Johannes Thumshirn <jthumshirn at suse.de>

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Johannes Thumshirn                                          Storage
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