and attach it back to the host kernel using pud(4). The result is
pretty much indistinguisable from if kernel drivers were used.
It's possible to e.g. mount a file system backed by the userspace
block device driver:
golem> disklabel ./rumpsd0d
[...]
5 partitions:
# size offset fstype [fsize bsize cpg/sgs]
d: 1994752 0 unused 0 0 # (Cyl. 0 - 3895)
e: 1994512 240 MSDOS # (Cyl. 0*- 3895)
golem> s mount_msdos ./rumpsd0a /mnt
mount_msdos: "./rumpsd0a" is a non-resolved or relative path.
mount_msdos: using "/usr/home/pooka/src/umserv/rumpsd0a" instead.
mount_msdos: /usr/home/pooka/src/umserv/rumpsd0a on /mnt: Device not configured
golem> s mount_msdos ./rumpsd0e /mnt
mount_msdos: "./rumpsd0e" is a non-resolved or relative path.
mount_msdos: using "/usr/home/pooka/src/umserv/rumpsd0e" instead.
golem> df -h /mnt
Filesystem Size Used Avail %Cap Mounted on
/usr/home/pooka/src/umserv/rumpsd0e 974M 5.2M 968M 0% /mnt
etcetc.