This patch changes all parallels/vz driver structure and
function prefixes from parallels to vz.
No functional changes.
Signed-off-by: NMaxim Nestratov <mnestratov@parallels.com>

Statistics provided through PCS SDK. As we have only async interface in SDK we
need to be subscribed to statistics in order to get it. Trivial solution on
every stat request to subscribe, wait event and then unsubscribe will lead to
significant delays in case of a number of successive requests, as the event
will be delivered on next PCS server notify cycle. On the other hand we don't
want to keep unnesessary subscribtion. So we take an hibrid solution to
subcsribe on first request and then keep a subscription while requests are
active. We populate cache of statistics on subscribtion events and use this
cache to serve libvirts requests.

 * Cache details.
Cache is just handle to last arrived event, we call this cache
as if this handle is valid it is used to serve synchronous
statistics requests. We use number of successive events count
to detect that user lost interest to statistics. We reset this
count to 0 on every request. If more than PARALLELS_STATISTICS_DROP_COUNT
successive events arrive we unsubscribe. Special value of -1
of this counter is used to differentiate between subscribed/unsubscribed state
to protect from delayed events.

Values of PARALLELS_STATISTICS_DROP_COUNT and PARALLELS_STATISTICS_TIMEOUT are
just drop-ins, choosen without special consideration.

 * Thread safety issues
Use parallelsDomObjFromDomainRef in parallelsDomainBlockStats as
we could wait on domain lock down on stack in prlsdkGetStatsParam
and if we won't keep reference we could get dangling pointer
on return from wait.
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@parallels.com>

This function is practically copied over from qemu driver. Its
only purpose in life is to lookup a domain object and print an
error if no object is found.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

The source code base needs to be adapted as well. Some files
include virutil.h just for the string related functions (here,
the include is substituted to match the new file), some include
virutil.h without any need (here, the include is removed), and
some require both.

scmd was used for debugging and I forgot to remove it before
commit, so remove it now.
Signed-off-by: NDmitry Guryanov <dguryanov@parallels.com>

Don't try to dereferece NULL pointer.

Parallels Cloud Server has one serious discrepancy with libvirt:
libvirt stores domain configuration files in one place, and storage
files in other places (with the API of storage pools and storage volumes).
Parallels Cloud Server stores all domain data in a single directory,
for example, you may have domain with name fedora-15, which will be
located in '/var/parallels/fedora-15.pvm', and it's hard disk image will be
in '/var/parallels/fedora-15.pvm/harddisk1.hdd'.

I've decided to create storage driver, which produces pseudo-volumes
(xml files with volume description), and they will be 'converted' to
real disk images after attaching to a VM.

So if someone creates VM with one hard disk using virt-manager,
at first virt-manager creates a new volume, and then defines a
domain. We can lookup a volume by path in XML domain definition
and find out location of new domain and size of its hard disk.
Signed-off-by: NDmitry Guryanov <dguryanov@parallels.com>

Add functions for create/shutdown/destroy and suspend/resume domain.
Signed-off-by: NDmitry Guryanov <dguryanov@parallels.com>

Parallels driver is 'stateless', like vmware or openvz drivers.
It collects information about domains during startup using
command-line utility prlctl. VMs in Parallels are identified by UUIDs
or unique names, which can be used as respective fields in
virDomainDef structure. Currently only basic info, like
description, virtual cpus number and memory amount, is implemented.
Querying devices information will be added in the next patches.

Parallels doesn't support non-persistent domains - you can't run
a domain having only disk image, it must always be registered
in system.

Functions for querying domain info have been just copied from
test driver with some changes - they extract needed data from
previously created list of virDomainObj objects.
Signed-off-by: NDmitry Guryanov <dguryanov@parallels.com>