The default dma alignment mask is 511, which is much larger than any nvme
controller requires. NVMe controllers accept qword aligned DMA addresses,
so set the request_queue constraints to that. This can help avoid bounce
buffers on user passthrough commands.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>