[PATCH v5 RFC] nvme: improve performance for virtual NVMe devices

[Keith Busch]

On Fri, Mar 24, 2017 at 01:23:43AM -0300, Helen Koike wrote:
> +	if (dev->ctrl.oacs & NVME_CTRL_OACS_DBBUF_SUPP) {
> +		result = nvme_dbbuf_dma_alloc(dev);
> +		if (result)
> +			goto out;
> +	}

We are still functional without enabling this feature, so I don't think
we should error out. Just log a warning that it's less than optimal.