ZFS: /dev/zvol does not exist

I have created a zpool named `ztank`, and then run:

zfs create -V 10G ztank/test1

I can see that it created /dev/zd0 so it appears to have worked. However I expected it would also exist at /dev/zvol/ztank/test1.

I want to use ZFS as a volume manager for Xen guests, so my fear is that the /dev/zdX names will not always persist between reboots.

Is there a way to enable this functionality on Alpine? Thank you!