Pull block fixes from Jens Axboe:
"Unfortunately a few issues that warrant sending another pull request,
even if I had hoped to avoid it. This contains:
- A fix for multiqueue xen-blkback, on tear down / disconnect.
- A few fixups for NVMe, including a wrong bit definition, fix for
host memory buffers, and an nvme rdma page size fix"
* 'for-linus' of git://git.kernel.dk/linux-block:
nvme: fix the definition of the doorbell buffer config support bit
nvme-pci: use dma memory for the host memory buffer descriptors
nvme-rdma: default MR page size to 4k
xen-blkback: stop blkback thread of every queue in xen_blkif_disconnect
501d9f7945