LVM operations can take significant amount of time. This is especially
visible when stopping a VM (`vm.storage.stop()`) - in that time the
whole qubesd freeze for about 2 seconds.
Fix this by making all the ThinVolume methods a coroutines (where
supported). Each public coroutine is also wrapped with locking on
volume._lock to avoid concurrency-related problems.
This all also require changing internal helper functions to
coroutines. There are two functions that still needs to be called from
non-coroutine call sites:
- init_cache/reset_cache (initial cache fill, ThinPool.setup())
- qubes_lvm (ThinVolume.export()
So, those two functions need to live in two variants. Extract its common
code to separate functions to reduce code duplications.
FixesQubesOS/qubes-issues#4283
Both vm.create_on_disk() and vm.start() are coroutines. Tests in this
class didn't run them, so basically didn't test anything.
Wrap couroutine calls with self.loop.run_until_complete().
Additionally, don't fail if LVM pool is named differently.
In that case, the test is rather sily, as it probably use the same pool
for source and destination (operation already tested elsewhere). But it
isn't a reason for failing the test.
Do not write directly to main volume, instead create temporary volume
and only commit it to the main one when operation is finished. This
solve multiple problems:
- import operation can be aborted, without data loss
- importing new data over existing volume will not leave traces of
previous content - especially when importing smaller volume to bigger
one
- import operation can be reverted - it create separate revision,
similar to start/stop
- easier to prevent qube from starting during import operation
- template still can be used when importing new version
QubesOS/qubes-issues#2256
First rename volume to backup revision, regardless of revisions_to_keep,
then rename -snap to current volume. And only then remove backup
revision (if exceed revisions_to_keep). This way even if commit
operation is interrupted, there is still a volume with the data.
This requires also adjusting few functions to actually fallback to most
recent backup revision if the current volume isn't found - create
_vid_current property for this purpose.
Also, use -snap volume for clone operation and commit it normally later.
This makes it safer to interrupt or even revert.
QubesOS/qubes-issues#2256
- improve TestPool mock - init_volume now return appropriate mock type,
instead of TestPool
- improve patching base directory (/var/lib/qubes) - it is stored in
more than one place...
- fix inheritance in TC_01_ThinPool class
- fix expected LVM volume names ('vm-' prefix)
- fix cleanup after FilePool tests - remove temporary qubes.xml
- asyncio usage
- better reporting in integ.storage - include error message in the
report, not only as a comment in code
Changed the inheritance hierarchy:
1. Renamed `SystemTestsMixin` to `SystemTestCase`
2. `SystemTestCase` is a child of `QubesTestCase`
3. All classes extending the prior `SystemTestsMixin` now just extend `object`
Reference objects, not their IDs - this way when object is modified, it
is visible everywhere where it is used. Main changes:
- volume.pool - Pool object
- volume.source - Volume object
Since volume have Pool object reference now, move volume related
functions into Volume class (from Pool class). This avoids horrible
`storage.get_pool(volume).something(volume)` construct.
One issue here is since volume.source reference a Volume object from a
different VM - VM's template, now VM load order is important. Since we
don't have control over it, initialize vm.storage when needed - possibly
while initializing storage of different VM. Since we don't have cycles
in AppVM-TemplateVM dependencies, it is safe.
Also, since this commit, volume.source (if defined) always points at
volume of the same name from VM's template. Using volumes with something
else as a source is no longer supported.
QubesOS/qubes-issues#2256
This requires creating LVM volume group, so create on based on loop dev
in /tmp.
This is rather rough, but if any of this fails, run the tests anyway -
it will simply skip LVM tests.
