User-Mode Linux was an alternative hypervisor that could run the
appliance, instead of using qemu. It had many limitations including
lack of network, and UML support in Linux has been semi-broken for a
long time. It was also slower than KVM on baremeal in general and had
various corner cases which were much slower including the emulated
serial port which made bulk uploads and downloads painful. Also of
course it lacked qemu-specific features like qcow2 or any
network-backed disk, so many disk images could not be opened this way.
This was never supported in RHEL.
See-also: https://bugzilla.redhat.com/1144197
Before this change the tests ran in about 12m34 and afterwards in
about 6m20, although the real change is more dramatic if you only run
tests from the tests/ subdirectory (as language tests still run serially).
This breaks valgrinding for now, which I intend to fix properly later.
Instead of hardcoding the location of perl (assuming it is installed in
/usr), use /usr/bin/env to run it, and thus picking it from $PATH.
This makes it possible to run these scripts also on installations with
perl in a different prefix than /usr.
Also, given that we want enable warnings on scripts, turn the -w
previously in shebang to explicit "use warnings;" in scripts which
didn't have it before.
Replaces code such as:
fd = open "test1.img"
ftruncate fd, size
close fd
g.add_drive "test1.img"
with the shorter and simpler:
g.add_drive_scratch size
New API: list-disk-labels
Allow the user to pass an optional disk label when adding a drive.
This is passed through to qemu / libvirt using the disk serial field,
and from there to the appliance which exposes it through udev,
creating a special alias of the device /dev/disk/guestfs/<label>.
Partitions are named /dev/disk/guestfs/<label><partnum>.
virtio-blk and virtio-scsi limit the serial field to 20 bytes. We
further limit the name to maximum 20 ASCII characters in [a-zA-Z].
list-devices and list-partitions are not changed: these calls still
return raw block device names. However a new call, list-disk-labels,
returns a hash table allowing callers to map between disk labels, and
block device and partition names.
This commit also includes a test.
