commit 048e5a07f2 upstream.
The block size for the dm-cache's data device must remained fixed for
the life of the cache. Disallow any attempt to change the cache's data
block size.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>