Disk hotplug has slightly different semantics from media changing. Move
the media change code out and add proper initialization of the new
source object and proper cleanups if something fails.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

In cases where we know the device is a disk we can avoid using the full
device definition.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

The disk hotplug code also overloads media change which is not ideal.
This will allow splitting out of the media change code.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

The disk storage source needs to be prepared if we want to use -blockdev
or secrets for the new media image. It does not hurt to do the same for
the legacy hotplug code as well.

Unfortunately helpers like qemuDomainPrepareDiskSource take
virDomainDiskDef as an argument and it would be hard to fix them to take
an explicit source, so the function also temporarily replaces disk->src
for the new source in this function.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

Some functions require us to replace disk->src with the new source for
them to work properly. To avoid confusion all places which allow
explicit virStorageSource should get the appropriate definition.

The legacy code fortunately does not need anything from the old source
so that does not require modifications.

Blockdev does require the old definition so we'll pass it explicitly.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

Since the code is also used when changing media we need to allow
specifying explicit source for which we are going to prepare. With this
change callers don't have to replace disk->src with the new source
definition for generating these.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

qemu media changing code tried to assume old media's format for the new
one if that was not specified. Since the format will always be present
it does not make sense to keep the code around.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

Old media changing code does not bother setting up the secrets for new
media or actually removing/adding of the corresponding objects.

Additionally it uses secrets setup for the old image to be removed as
the secret for the new image which is wrong.

Remove the support for secrets while changing media for the legacy
approach. The only reasonable way to fix it is when using blockdev.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

While the idea was good the implementation not so much as we need to
take into account the old disk data and the new source. The code will be
consolidated later in a different way.

This reverts commit 663b1d55.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

Preparing the storage source prior to assigning the alias will not work
as the names of the certain objects depend on the alias for the legacy
hotplug case as we generate the object names for the secrets based on
the alias.

This reverts commit 192fdaa6.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

For non-Linux platforms we have
virHostValidateCGroupControllers() stub which only reports an
error. But we are not marking the ignored arguments the way we
should.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NPavel Hrdina <phrdina@redhat.com>

Cgroup freezer support for LXC was added in libvirt-0.7.2.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

This removes code duplication and simplifies cgroup detection.
As a drawback we will not have separate messages to enable cgroup
controller in kernel or to mount it.  On the other side the rewrite
adds support for cgroup v2.

The kernel config support was wrong because it was parsing
'/proc/self/cgroup' instead of '/proc/cgroups/' file.

The mount suggestion is removed as well because it will not work
with cgroup v2.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

We need to configure multiple env variables for each set of tests so
create helper functions to do that.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

We need to create the cgroup v2 sysfs the same way as we do for
cgroup v1.

This introduces new VIR_CGROUP_MOCK_MODE env variable which will
configure which cgroup mode each test requires.  There are three
different modes:

    - legacy: only cgroup v1 is available and it's the default mode
    - hybrid: both cgroup v1 and cgroup v2 are available and have some
        controllers
    - unified: only cgroup v2 is available
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Remove the trailing '/' from prefix.  This change is required in order
to introduce tests for unified cgroups.  They are usually mounted in
'/sys/fs/cgroup'.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

This enables to use both cgroup v1 and v2 at the same time together
with libvirt.  It is supported by kernel and there is valid use-case,
not all controllers are implemented in cgroup v2 so there might be
configurations where administrator would enable these missing
controllers in cgroup v1.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

All mandatory callbacks are implemented for cgroup v2 backend so we
can register it now.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

In order to set CPU cfs period using cgroup v2 'cpu.max' interface
we need to load the current value of CPU cfs quota first because
format of 'cpu.max' interface is '$quota $period' and in order to
change 'period' we need to write 'quota' as well.  Writing only one
number changes only 'quota'.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>