The intent here is to allow the virt drivers to be run directly embedded
in an arbitrary process without interfering with libvirtd. To achieve
this they need to store all their configuration & state in a separate
directory tree from the main system or session libvirtd instances.
This can be useful for doing testing of the virt drivers in "make check"
without interfering with the user's own libvirtd instances.
It can also be used for applications using KVM/QEMU as a piece of
infrastructure to build an service, rather than for general purpose
OS hosting. A long standing example is libguestfs, which would prefer
if its temporary VMs did show up in the main libvirtd VM list, because
this confuses apps such as OpenStack Nova. A more recent example would
be Kata which is using KVM as a technology to build containers.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
When running in libvirtd, we are happy for any of the drivers to simply
skip their initialization in virStateInitialize, as other drivers are
still potentially useful.
When running in per-driver daemons though, we want the daemon to abort
startup if the driver cannot initialize itself, as the daemon will be
useless without it.
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1685151
This reverts commit e4a969092b.
Now that drivers may call virConnectOpen() on secondary drivers, it
doesn't make much sense to have autostart separated from driver
initialization callback. In fact, it creates a problem because one
driver during its initialization might try to fetch an object from
another driver but since the object is yet to be autostarted the fetch
fails. This has been observed in reality: qemu driver performs
qemuProcessReconnect() during qemu's stateInitialize phase which may
call virDomainDiskTranslateSourcePool() which connects to the storage
driver to look up the volume. But the storage driver did not autostart
its pools yet therefore volume lookup fails and the domain is killed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Require that all headers are guarded by a symbol named
LIBVIRT_$FILENAME
where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.
Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
With the large number of APIs in libvirt the driver.h file,
it is easy to get lost looking for things. Split each driver
into a separate header file based on the functional driver
groups.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>