On Mon, Aug 28, 2017@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>

-- 
Johannes Thumshirn                                          Storage
jthumshirn at suse.de                                +49 911 74053 689
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