Make the Xen domain scheduler parameter methods directly
call into XenD or Xen hypervisor drivers
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Make the domain attach/dettach driver methods directly call
into either the XenD or XM drivers
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Make the domain define/undefine driver methods directly call
into either the XenD or XM drivers
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Directly call either the XenD or XM driver when starting
a persistent domain
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Directly call either XenD or the XM driver for handling
domain define operations.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

All the migration code is done by the XenD subdriver which
can be assumed to always be present
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The xenUnifiedDomainGetXMLDesc driver can assume that
the XM and XenD drivers are always present
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Unconditionally call the XenD APIs for save/restore, since that
driver will always be open.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Make the xenUnifiedDomainGetInfo and xenUnifiedDomainGetState drivers
call the correct sub-driver APIs directly.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Simplify the Xen memory limit driver methods to directly call
the most appropriate sub-driver
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The xenGetHostname entry point in the xenUnifiedDriver table
was unused.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Make xenUnifiedDomainGetOSType directly call either the
xenHypervisorDomainGetOSType or xenDaemonDomainGetOSType
method depending on whether the domain is active or not.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Unconditionally call the xenDaemonDomainDestroyFlags API
since the XenD driver is always available.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Make the xenUnifiedDomainShutdownFlags and xenUnifiedDomainReboot
driver methods unconditionally call the XenD APIs for shutdown
and reboot. Delete the unreachable impls in the XenStore driver.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Update xenUnifiedDomainSuspend and xenUnifiedDomainResume to
unconditionally invoke the XenD APIs for suspend/resume. Delete
the impls in the hypervisor driver which was unreachable.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Unconditionally call xenDaemonLookupByUUID, since the XenD
driver must always be present.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Unconditionally invoke the xenHypervisorLookupDomainByID,
xenHypervisorLookupDomainByUUID or xenDaemonLookupByName
for looking up domains. Fallback to xenXMDomainLookupByUUID
and xenXMDomainLookupByName for legacy XenD without inactive
domain support
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Unconditionally call xenDaemonCreateXML in the
xenUnifiedDomainCreateXML driver, since the XenD
driver is always present.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The XenStore driver is mandatory, so it can be used unconditonally
for the xenUnifiedConnectListDomains & xenUnifiedConnectNumOfDomains
drivers. Delete the unused XenD and Hypervisor driver code for
listing / counting domains
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Unconditionally call into xenHypervisorGetMaxVcpus and
xenDaemonNodeGetInfo respectively, since those drivers
are both mandatory
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The hypervisor driver is mandatory, so the the call to
xenHypervisorGetVersion must always succeed. Thus there
is no need to ever run xenDaemonGetVersion
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

There is no point iterating over sub-drivers since the user
would not have a virConnectPtr instance at all if opening
the drivers failed. Just return 'Xen' immediately.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Since the Xen driver was changed to only execute inside libvirtd,
there is no scenario in which it will be opened from a non-privileged
context. Thus all the code dealing with opening the sub-drivers can
be simplified to assume that they are always privileged.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The Xen driver uses a macro GET_PRIVATE as a supposed shorthand
for 'xenUnifiedPrivatePtr priv = (xenUnifiedPrivatePtr) (conn)->privateData'.
It does not in fact save any lines of code, and obscures what is
happening. Remove it, since it adds no value.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Some of the Xen sub-drivers have checks against the
VIR_CONNECT_RO flag. This is not required, since such
checks are done at the top level before the driver
methods are invoked
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The Xen hypervisor driver checks for 'priv->handle < 0' and
returns -1, but without raising any error. Fortunately this
code will never be executed, since the main Xen driver always
checks 'priv->opened[XEN_UNIFIED_HYPERVISOR_OFFSET]' prior
to invoking any hypervisor API. Just remove the redundant
checks for priv->handle
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>