cloud-init's SLAAC option was disabled in 2018 because there was no
support for it. Now that cloud-init 19.4 or newer versions are more
widespread, we can finally reenable it.
Also include minimum required cloud-init version for SLAAC support in
format description.
Tested on Ubuntu 20.04 (ci 20.4), CentOS 8 (ci 19.4), Debian 10 (ci
20.2).
Signed-off-by: Mira Limbeck <m.limbeck@proxmox.com>
In testing this usually completes almost immediately, but in theory this
is a storage/IO operation and as such can take a bit to finish. It's
certainly not unthinkable that it might take longer than the default *3
seconds* we've given it so far. Make it a minute.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
A "savevm" call (both our async variant and the upstream sync one) use
migration code internally. As such, they both expect migration
capabilities to be set.
This is usually not a problem, as the default set of capabilities is ok,
however, it leads to differing snapshot settings if one does a snapshot
after a machine has been live-migrated (as the capabilities will persist
from that), which could potentially lead to discrepencies in snapshots
(currently it seems to be fine, but it still makes sense to set them to
safeguard against future changes).
Note that we do set the "dirty-bitmaps" capability now (if
query-proxmox-support reports true), which has three effects:
1) PBS dirty-bitmaps are preserved in snapshots, enabling
fast-incremental backups to work after rollback (as long as no newer
backups exist), including for hibernate/resume
2) snapshots taken from now on, with a QEMU version supporting bitmap
migration, *might* lead to incompatibility of these snapshots with
QEMU versions that don't know about bitmaps at all (i.e. < 5.0 IIRC?)
- forward compatibility is still given, and all other capabilities we
set go back to very old versions
3) since we now explicitly disable bitmap saving if the version doesn't
report support, we avoid crashes even with not-updated QEMU versions
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
At this stage, there are no keys in %storage_limits to iterate over. The
refactoring in commit 9f3d73bc35 broke the logic
by accident.
Also explicitly set zero if there is no limit to avoid repeating the
get_bandwith_limit call for the same storage. When accessing the value later,
zero is already correctly handled as 'no limit'.
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
and use file_set_contents to really commit it afterwards. Mostly done as a
preparation for the later patch for sanitizing the config on restore, but
shouldn't hurt by itself either.
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
A fix for violating a important standard for booting[0] in recently
packaged QEMU 5.2 surfaced some issues with Windows based VMs in our
forum[1], which seem to be quite sensitive for such changes (it seems
they derive lots of their device assignment from ACPI).
User visible effects are loss of any network configuration due to
windows thinking it was swapped with a new one, and starts with a
fresh config - this is mostly problematic for setups with static
address assignment.
There may be lots of other, more subtle, effects and the PVE admin is
also not always the VM admin, so we really need to avoid such
negative effects. Do this by pinning the version of any windows based
VMs to either the minimum of (5.1, kvm-version) for existing VMs or
the kvm-version at time of VM creation for new ones.
There are patches in pve-manager for user to be able to change the
pinned version themself in the webinterface, so this can now also get
adapted more easily if there surface any other issues (with new or
old version) in the future.
0: https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg08484.html
1: https://forum.proxmox.com/threads/warning-latest-patch-just-broke-all-my-windows-vms-6-3-4-patch-inside.84915/page-2#post-373331
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Moving to Ceph is very slow when bs=1. Instead, use a larger block size in
combination with the (currently) PVE-specific osize option to specify the
desired output size.
Suggested-by: Dietmar Maurer <dietmar@proxmox.com>
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
currently only pending changes are applied when we regenerate
image on a running vm, but not the pending delete.
Signed-off-by: Alexandre Derumier <aderumier@odiso.com>
by checking if the vm is paused at the beginning and skipping the
resume now we also skip the qga freeze/thaw (which cannot work if the
vm is paused)
moved the 'vm_is_paused' sub from the api to PVE/QemuServer.pm so it
is available everywhere we need it.
since a suspend backup would pause the vm anyway, we can skip that
step also
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Tested-by: Fabian Ebner <f.ebner@proxmox.com>
this was previously covered by the "lets destroy ever disk which
matches the VMID" feature we disarmed a bit.
As unused disks are referenced in the config, it is not subtle to
destroy them (and we always did in the past) so fix that regression
again for explicitly referenced but unused disks.
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Since an old change released with a version bump on 2009-09-07, we
search all enabled storages for VMID maching volumes on VM removal
and purge those too.
This has multiple pitfalls and may be quite unexpected for some
users.
It can make problems when:
* on recovery a VM is created, before disks are reattached the admin
notices some settings issues and chooses to just recreate the VM;
but during destroying the dummy VM all related disks get destroyed
unconditionally which may result in data loss. This actually
happened and is the original reason for the decision to change
this.
* a storage is shared between PVE instance (between a set of clusters
and/or single nodes), while this is against our rules it may still
come as a surprise if destroying a VM on node A may destroy
unrelated and unreferenced disks on the unrelated node B without
asking or allowing to avoid that.
As this the removal of matching but unreferenced disks can result in
permanent data loss (up to the last backup) and may be to subtle and
unforgiving, allow to opt-out of it.
In the long run we want to make this opt-in, but that is an API
change and so needs to wait for next major release. But, we can adapt
the GUI already to make it opt-in there, catching most of the cases.
side-note: CT do not have this behavior at all
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
On clone_vm when cloning the disks while the VM is running, we use
drive-mirror. We skip completion until the last disk, but with a
cloudinit disk there's no drive-mirror and so no completion done. If it
is the last disk in the hash, we never complete the drive-mirror jobs
and no further cloning is possible as there are already active jobs
using the disks.
To fix it we have to call qemu_drive_mirror_monitor directly in the case
of cloudinit when completion is requested and there are jobs defined.
Signed-off-by: Mira Limbeck <m.limbeck@proxmox.com>
The phrasing left some room for speculation when this would be triggered.
E.g. after cloning a full VM?
Currently the only instances where it is used is when a disk is moved or
a VM migrated.
Signed-off-by: Aaron Lauterer <a.lauterer@proxmox.com>
We only added the format extension when it was not 'raw'. But on file level
storages we always require it. To fix this, always add the format
extension if the storage provides the 'path' property.
This is the same logic we use in create_disks for cloudinit disks.
Signed-off-by: Mira Limbeck <m.limbeck@proxmox.com>
by partially reverting 4df98f2f14 and fixing the
line-length issue differently. The commit didn't update two later usages of
$size, breaking copying the efidisk. The other usage as a parameter to
qemu_img_convert() is luckily only cosmetic, for progress output.
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
this fixes the issue that we did not generate the correct repository
url for pbs storages that contained an ipv6 address or a port
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Extends print_recursive_hash for the CLI to handle JSON booleans so the
result will actually show up in 'qm status --verbose'.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
When the VM is in status 'shutdown', i.e. after the guest issues a
powerdown while a backup is running, QEMU requires a 'system_reset' to
be issued before 'cont' can boot the guest again.
Additionally, when the VM has been powered down during a backup, the
logically correct call would be a 'vm_start', so automatically vm_resume
from vm_start in case this situation occurs. This also means the GUI can
cope with this almost unchanged.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
Ignore shutdowns triggered from within the guest in favor of detecting
them via qmeventd and stopping the QEMU process that way.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
by adding the missing argument (otherwise all the other ones are shifted
one slot to the left, which is of course bogus).
this has been broken since 2018 (d559309), but was only made
visible/caused a failure with the recent changes adding
use strict;
use warnings;
to PVE::QemuServer::PCI
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
We query QEMU if it's safe before enabling it, as on versions without
the necessary patches it not only would be useless, but can actually
lead to hangs.
PBS state is always migrated, as it's a small amount of data anyway, so
we don't need to set a specific flag for it.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
Specifying 'boot: order=' was intended to be used for an empty bootorder
(i.e. no boot devices), but as it turns out our format parser doesn't
like empty '-list' properties if they are nested in a subformat.
Fixing this in JSONSchema sounds like a risky move, so instead just
write 'boot: ' (without 'order=') to indicate an empty bootorder. The
rest of the code handles it just fine, as this was valid before too.
Incidentally also fixes a bug where you couldn't create a new VM without
any disks if no explicit 'boot' property was specified (i.e. a simple
'qm create 100' without any parameters would fail).
Reported-by: Dominic Jäger <d.jaeger@proxmox.com>
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
fixes commit 74c17b7a23 which moved
this code here, but forgot to pass $vga ref, as the module was not
using warning nor strict mode this was not caught..
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
After migration or a rollback the cloudinit disk might not be allocated, so
volume_size_info() fails. As we override the value anyway for cloudinit
and efi disks simply move the volume_size_info() call into the 'else'
branch.
Signed-off-by: Mira Limbeck <m.limbeck@proxmox.com>
(also fixes#3011)
Deprecates the old-style 'boot' and 'bootdisk' options by adding a new
'order=' subproperty to 'boot'.
This allows a user to specify more than one disk in the boot order,
helping with newer versions of SeaBIOS/OVMF where disks without a
bootindex won't be initialized at all (breaks soft-raid and some LVM
setups).
This also allows specifying a bootindex for USB and hostpci devices,
which was not possible before. Floppy boot support is not supported in
the new model, but I doubt that will be a problem (AFAICT we can't even
attach floppy disks to a VM?).
Default behaviour is intended to stay the same, i.e. while new VMs will
receive the new 'order' property, it will be set so the VM starts the
same as before (using get_default_bootorder).
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
The format is unused in this commit, but will replace the current
string-based format of the 'boot' property. It is included since the
parameter of bootorder_from_legacy follows it.
Two helper methods are introduced:
* bootorder_from_legacy: Parses the legacy format into a hash closer to
what the new format represents
* get_default_bootdevices: Encapsulates the legacy default behaviour if
nothing is specified in the boot order
resolve_first_disk is simplified and gets a new $cdrom parameter to
control the behaviour of excluding CD-ROMs or instead searching for only
them.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
We already keep hugepages if they are created with the kernel
commandline (hugepagesz=x hugepages=y), but some setups (specifically
hugepages across multiple NUMA nodes) cannot be configured that way.
Since we always clear these hugepages at VM shutdown, rebooting a VM
that uses them might not work, since the requested count might not be
available anymore by the time we want to use them (also, we would then
no longer allocate them correctly on the NUMA nodes).
Add a 'keephugepages' parameter to skip cleanup and simply leave them
untouched.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
until we maybe have a 'pbs-backup' that links Qemu and PBS like
'pbs-restore', we need to do a regular backup for the template case to
support all storage types and image formats.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Otherwise a warning is printed if the bios is not set in the config.
reported via community forum:
https://forum.proxmox.com/threads/warning-in-qemuserver.74683/
reproduced and tested that the patch fixes the issue.
Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
Edid support was added with Qemu 5. Windows guests seem to not be able
to get all possible resolutions if the default std VGA device is used as
GPU and the VM boots in BIOS mode. The result is that only one of the
following three resolutions can be configured:
800x600
1024x768
1920x1080
It is important to note that just booting a Windows VM with the edid=off
parameter will not make the large list of resolutions available. It
seems that Windows is caching the list of possible resolutions
somewhere [0].
Uninstalling the 'Microsoft Basic Display Adapter' in the device manager
and rebooting the VM is one way I found to force Windows to recreate the
list of possible resolutions.
Signed-off-by: Aaron Lauterer <a.lauterer@proxmox.com>
[0] https://lists.nongnu.org/archive/html/qemu-devel/2020-07/msg07128.html
In config_to_command, '-loadstate' will be added whenever there is a
vmstate in the config. But in vm_start_nolock, the resume parameter
is used to calculate the appropriate timeout and to remove the vmstate
after the start. The resume parameter was only set if there is a
'suspended' lock, but apparently [0] we cannot rely on the lock to be
set if and only if there is a vmstate.
[0]: https://forum.proxmox.com/threads/task-error-start-failed.72450
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
during refactoring, the vmid got lost, but is necessary to get
the correct mdev id
Fixes commit 74c17b7a23
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
[ reference fixed commit ]
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
pbs-restore might not stay there like that forever and if
this code path changes we should remember to also remove the
environment variables
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Pass new size directly, so the function doesn't need to know about
how some hash is organized. And return a message directly, instead
of both size-strings. Also dropped the wantarray, because both
existing callers use the message anyways.
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
Legacy IGD passthrough requires address 00:1f.0 to not be assigned to
anything on QEMU startup (currently it's assigned to bridge pci.2).
Changing this in general would break live-migration, so introduce a new
hostpci parameter "legacy-igd", which if set to 1 will move that bridge
to be nested under bridge 1.
This is safe because:
* Bridge 1 is unconditionally created on i440fx, so nesting is ok
* Defaults are not changed, i.e. PCI layout only changes when the new
parameter is specified manually
* hostpci forbids migration anyway
Additionally, the PT device has to be assigned address 00:02.0 in the
guest as well, which is usually used for VGA assignment. Luckily, IGD PT
requires vga=none, so that is not an issue either.
See https://git.qemu.org/?p=qemu.git;a=blob;f=docs/igd-assign.txt
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
netdev_add is now a proper qmp command, which means that it verifies
the parameter types properly
instead of sending strings, we now have to choose the correct
types for the parameters
bool for vhost
and uint64 for queues
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
the special case was dropped when moving this to pve-storage.
fixes commit c6d517835a
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
fixes commit 940e2a3a06
QEMU 4.1 will fail to start a guest with an audio device set with:
> Property '.audiodev' not found
Signed-off-by: Aaron Lauterer <a.lauterer@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
If /dev/hwrng exists, but no actual generator is connected (or it is
disabled on the host), QEMU will happily start the VM but crash as soon
as the guest accesses the VirtIO RNG device.
To prevent this unfortunate behaviour, check if a useable hwrng is
connected to the host before allowing the VM to be started.
While at it, clean up config_to_command by moving new and existing rng
source checks to a seperate sub.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
It's possible to have a VM with OVMF but without an efidisk, so don't
call parse_drive on a potential undef value.
Partial revert of 818c3b8d91 ("cfg2cmd: ovmf: code cleanup")
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
lock_file is used by PVE::QemuServer::Memory, but it does properly 'use
PVE::Tools ...' itself so we can drop them in the main module.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
regex to reduce the code duplication, as archive_info and
decompressor_info provides the same information as well.
Signed-off-by: Alwin Antreich <a.antreich@proxmox.com>
and refactor the test_volid closure. Like this get_replicatable_volumes doesn't
need a separate loop for unused volumes anymore. For get_vm_volumes, which is used
for activation/deactivation of volumes at migration and deactivation in vm_stop_cleanup,
includes those volumes now. For migration it's an improvement, because those volumes
might need to be migrated and for vm_stop_cleanup it shouldn't hurt. The last user
of foreach_volid is check_vm_disks_local used by migrate_vm_precondition,
where information about the additional volumes doesn't hurt either.
Note that replicate is (still) set by default, so the behavior for
get_replicatable_volumes for unused volumes should not change.
Hibernation vmstate files are now also included and recognized as 'is_vmstate'.
The 'size' attribute will not be overwritten by subsequent iterations for the
same volid anymore (a volid may appear both in the config and in snapshots),
so the size from the current config is now preferred.
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
when a backup includes a cloudinit disk on a non-existent storage,
the restore fails with 'storage' does not exist
this happens because we want to get the format of the disk, by
checking the source storage
we fix this by using the target storage first and only the source as
fallback
this will still fail if neither storage exists
(which is ok, since we cannot restore then anyway)
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
With Qemu 4.2 a new `audiodev` property was introduced [0] to explicitly
specify the backend to be used for the audio device. This is accompanied
with a warning that the fallback to the default audio backend is
deprecated.
[0] https://wiki.qemu.org/ChangeLog/4.2#Audio
Signed-off-by: Aaron Lauterer <a.lauterer@proxmox.com>
This makes it possible to migrate a VM with volumes store1:vm-123-disk-0
store2:vm-123-disk-0 to some targetstorage. Also prevents migration failure
when there is an orphaned disk with the same volid on the target.
To avoid confusion, the name should not change for 'vmstate'-volumes.
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
It was necessary to move foreach_volid back to QemuServer.pm
In VZDump/QemuServer.pm and QemuMigrate.pm the dependency on
QemuConfig.pm was already there, just the explicit "use" was missing.
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
Upstream marks these as having a micro-version of >=90, unfortunately the
machine versions are bumped earlier so testing them is made unnecessarily
difficult, since the version checking code would abort on migrations etc...
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
[ Thomas: do so refactor ]
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
so that pve-container and qemu-server use the same one, in preparation
for moving it to JSONSchema and having a bridgepair format.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Just like with live-migration, custom CPU models might change after a
snapshot has been taken (or a VM suspended), which would lead to a
different QEMU invocation on rollback/resume.
Save the "-cpu" argument as a new "runningcpu" option into the VM conf
akin to "runningmachine" and use as override during rollback/resume.
No functional change with non-custom CPU types intended.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
This is required to support custom CPU models, since the
"cpu-models.conf" file is not versioned, and can be changed while a VM
using a custom model is running. Changing the file in such a state can
lead to a different "-cpu" argument on the receiving side.
This patch fixes this by passing the entire "-cpu" option (extracted
from /proc/.../cmdline) as a "qm start" parameter. Note that this is
only done if the VM to migrate is using a custom model (which we can
check just fine, since the <vmid>.conf *is* versioned with pending
changes), thus not breaking any live-migration directionality.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
in addition to printing it. preparation for remote cluster migration,
where we want to return this in a structured fashion over the migration
tunnel instead of parsing stdout via SSH.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
into one sub that retrieves the local disks, and the actual NBD
allocation. that way, remote incoming migration can just call the NBD
allocation with a custom list of volume names/storages/..
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
the syntax is backwards compatible, providing a single storage ID or '1'
works like before. the new helper ensures consistent behaviour at all
call sites.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
as preparation of targetstorage mapping and remote migration. this also
removes re-using of the $local_volumes hash in the original code.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
to start breaking up vm_start before extending parts for new migration
features like storage and network mapping.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
as preparation for refactoring it further. remote migration will add
another 1-2 parameters, and it is already unwieldly enough as it is.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
on storages where the minimum size of images is bigger than the real
OVMF_VARS.fd file, they get padded to their minimum size
when using such an image, qemu maps it fully to the vm, but the efi
does not find the vars region and creates a file on the first efi
partition it finds
this breaks some settings in the ovmf, such as resolution
to fix this, we have to specify the size for the pflash, so that
qemu only maps the first n bytes in the vm (this only works for
raw files, not for qcow2)
we also have to use the correct size when converting between storages
in 'clone_disk' (used for move disk and cloning vms) and when
live migrating to different storages
when we now expect that the source image is always correctly used/created
(e.g. raw with size=x in pflash argument) then we always create the
target correctly
when encountering users which have a non-valid image (e.g. a efidisk
moved from zfs to qcow2 before this patch), we have to tell them to
recreate the efidisk and the settings on it
we have to version_guard it to 4.1+pve2 (since we haven't bumped yet
since the change to pve2)
also add 2 tests, one for the old version and one for the new
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Tested-by: Stefan Reiter <s.reiter@proxmox.com>
Reviewed-by: Stefan Reiter <s.reiter@proxmox.com>
[ Thomas: rebased to master ]
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
by only checking for replicatable volumes when a replication job is
defined, and passing only actually replicated volumes to the target node
via STDIN, and back via STDOUT.
otherwise this can pick up theoretically replicatable, but not actually
replicated volumes and treat them wrong.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
$cpu_fmt is being reused for custom CPUs as well as VM-specific CPU
settings. The "pve-vm-cpu-conf" format is introduced to verify a config
specifically for use as VM-specific settings.
"pve-cpu-conf" is registered for use in custom CPU API calls (where no
additional checks are required).
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
There is a need to set $noerr, because otherwise migration for a
VM with a non-replicatable volume fails with:
missing replicate feature on volume 'myfs:107/vm-107-disk-2.raw'
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
with incremental drive-mirror and dirty-bitmap tracking.
1.) get replicated disks that are currently referenced by running VM
2.) add a block-dirty-bitmap to each of them
3.) replicate ALL replicated disks
4.) pass bitmaps from 2) to drive-mirror for disks from 1)
5.) skip replicated disks when cleaning up volumes on either source or
target
added error handling is just removing the bitmaps if an error occurs at
any point after 2, except when the handover to the target node has
already happened, since the bitmaps are cleaned up together with the
source VM in that case.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Tested-by: Stefan Reiter <s.reiter@proxmox.com>
by re-using a dirty bitmap that represents changes since the divergence
of source and target volume. requires a qemu that supports incremental
drive-mirroring, and will die otherwise.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Tested-by: Stefan Reiter <s.reiter@proxmox.com>
