Logical and physical block sizes in QEMU are limited to 32 KiB.
This appears unnecessarily tight, and we've seen bigger block sizes
handy at times.
Lift the limitation up to 2 MiB which appears to be good enough for
everybody, and matches the qcow2 cluster size limit.
Signed-off-by: Roman Kagan <rvkagan@yandex-team.ru>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200528225516.1676602-9-rvkagan@yandex-team.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>