Replace the dax_host_hash with an xarray indexed by the pointer value
of the gendisk, and require explicitly calls from the block drivers that
want to associate their gendisk with a dax_device.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NMike Snitzer <snitzer@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20211129102203.2243509-5-hch@lst.deSigned-off-by: NDan Williams <dan.j.williams@intel.com>