Re: [PATCH 2/2] scsi: Align queue to ARCH_DMA_MINALIGN in non-coherent DMA mode

From: Christoph Hellwig
Date: Mon Sep 11 2017 - 03:39:21 EST

> + if (plat_device_is_coherent(dev))

We can't just call platform device code. We'll need a proper
DMA API call for this.

> + blk_queue_dma_alignment(q, 0x04 - 1);
> + else
> + blk_queue_dma_alignment(q, dma_get_cache_alignment() - 1);

Which we already have with dma_get_cache_alignment, except that it
doesn't take a struct device pointer and doesn't call into dma_map
ops. So please add a struct device argument to dma_get_cache_alignment,
and let it call into dma_map_ops where needed.

With that you can replace the above with:

max(0x04U, dma_get_cache_alignment(dev)) - 1);