Commit Graph

8103 Commits

Author SHA1 Message Date
Ján Tomko
2c5dd1ee4c qemu.conf: add vnc_tls_x509_secret_uuid
Add an option that lets the user specify the secret
that unlocks the server TLS key.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-22 12:18:28 +01:00
Ján Tomko
0b3fc37e61 qemu_process: fix debug message
Be generic instead of trying to enumerate all the involved
device types.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-22 12:18:28 +01:00
Ján Tomko
2c7791a869 qemu: prepare secret for the graphics upfront
Instead of hardcoding the TLS creds alias in
qemuBuildGraphicsVNCCommandLine, store it
in the domain private data.

Given that we only support one VNC graphics
and thus have only one alias per-domain,
this is overengineered, but it will allow us
to prepare the secret upfront when we start
supporting encrypted server TLS keys.

Note that the alias is not formatted anywhere
since we won't need to access it after domain
startup.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-22 12:18:28 +01:00
Ján Tomko
ea3c3f8846 qemu: add qemuDomainGraphicsPrivate data with a tlsAlias
Also introduce the necessary callbacks.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-22 12:18:28 +01:00
Ján Tomko
5de4d410a2 virQEMUDriverConfigLoadSWTPMEntry: use VIR_AUTOFREE
Switch the function to use VIR_AUTOFREE and VIR_AUTOPTR macros
to get rid of the cleanup section.

Requested-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-01-21 17:14:29 +01:00
Ján Tomko
784e690ecb virQEMUDriverConfigLoadSecurityEntry: use VIR_AUTOFREE
Switch the function to use VIR_AUTOFREE and VIR_AUTOPTR macros
to get rid of the cleanup section.

Requested-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-01-21 17:14:29 +01:00
Ján Tomko
2a33dc41bb virQEMUDriverConfigLoadNVRAMEntry: use VIR_AUTOFREE
Switch the function to use VIR_AUTOFREE and VIR_AUTOPTR macros
to get rid of the cleanup section.

Requested-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-01-21 17:14:29 +01:00
Ján Tomko
92e601d08c virQEMUDriverConfigLoadProcessEntry: use VIR_AUTOFREE
Switch the function to use VIR_AUTOFREE and VIR_AUTOPTR macros
to get rid of the cleanup section.

Requested-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-01-21 17:14:29 +01:00
Peter Krempa
f80eae8c2a qemu: command: Don't format image properties for empty -drive
If a -drive has no image, using image properties makes qemu whine that
they should not be used.

This patch stops formating cache/readonly/... for empty drives
for the pre-blockdev syntax. Unfortunately those parameters can't be
added later when inserting media, but on the other hand qemu will start
with an empty drive.

Since we already were able to start a VM with such config previously due
to qemu ignoring them I've opted just to skip formatting them.
Additionally with -blockdev support it will work as expected as the
image properties will be formatted when adding the image itself which is
not possible without it.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1651457

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-01-21 17:04:26 +01:00
Laine Stump
40136bd316 qemu: fix i6300esb watchdog hotplug on Q35
When commit 361c8dc17 added support for hotplugging the i6300esb
watchdog device (first in libvirt-3.9.0), it accidentally contstructed
the commandline for the device_add command before allocating a PCI
address for the device. With no PCI address specified in the command,
the watchdog would simply be placed at the lowest unused PCI slot.

On a 440fx guest, this doesn't cause a problem, because libvirt's PCI
address allocation algorithm would most likely give the same address
anyway (usually a slot on pci-root), so nobody noticed the omission of
address from the command.

But on a Q35 guest, the lowest unused PCI slot is on pcie-root, which
doesn't support hotplug; libvirt knows enough to assign a PCI address
that is on a pcie-to-pci-bridge (because its slots *do* support
hotplug), but qemu doesn't, so if there is no PCI address in the
command, qemu just tries to plug the new device into pcie-root, and
fails because it doesn't support hotplug, e.g.:

  error: Failed to attach device from watchdog.xml
  error: internal error: unable to execute QEMU command 'device_add':
  Bus 'pcie.0' does not support hotplugging

The solution is simply to build the command string after assigning a
PCI address, not before.

Resolves: https://bugzilla.redhat.com/1666559
Signed-off-by: Laine Stump <laine@laine.org>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 14:12:02 -05:00
Wang Yechao
01ca4010d8 qemu: Assign device addresses earlier in qemuDomainAttachNetDevice
If code in the @actualType switch needs to have/know which PCI
Address is being used, then we must assign it earlier. In particular
a vhost-user device needs to call qemuDomainSupportsNicdev which
requires an address to be defined.

Signed-off-by: Wang Yechao <wang.yechao255@zte.com.cn>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 10:11:50 -05:00
Ján Tomko
e6df863294 qemu_conf: rename checkdefaultTLSx509certdir
Use defaultTLSx509certdirPresent for consistencty.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:07 +01:00
Ján Tomko
4079f47677 qemu_conf: split out virQEMUDriverConfigLoadDefaultTLSEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:07 +01:00
Ján Tomko
cfe99a336d qemu_conf: split out virQEMUDriverConfigLoadVNCEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:07 +01:00
Ján Tomko
53680aa379 qemu_conf: split out virQEMUDriverConfigLoadNographicsEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:07 +01:00
Ján Tomko
da3dc5a382 qemu_conf: split out virQEMUDriverConfigLoadSPICEEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:07 +01:00
Ján Tomko
a0ac0b913e qemu_conf: split out virQEMUDriverConfigLoadSpecificTLS
Split out parts of the config parsing code to make
the parent function easier to read.

This is the only patch that mixes various augeas entry
groups in one function.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:07 +01:00
Ján Tomko
de100ceddb qemu_conf: split out virQEMUDriverConfigLoadRemoteDisplayEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:07 +01:00
Ján Tomko
1195e10b98 qemu_conf: split out virQEMUDriverConfigLoadSaveEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:06 +01:00
Ján Tomko
0ebe4e60e6 qemu_conf: split out virQEMUDriverConfigLoadProcessEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:06 +01:00
Ján Tomko
00063c2c95 qemu_conf: split out virQEMUDriverConfigLoadDeviceEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:06 +01:00
Ján Tomko
e79e0cacc5 qemu_conf: split out virQEMUDriverConfigLoadRPCEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:06 +01:00
Ján Tomko
a780ee8ab5 qemu_conf: split out virQEMUDriverConfigLoadNetworkEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:06 +01:00
Ján Tomko
f78c3dde57 qemu_conf: split out virQEMUDriverConfigLoadLogEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:06 +01:00
Ján Tomko
627595641d qemu_conf: split out virQEMUDriverConfigLoadNVRAMEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:06 +01:00
Ján Tomko
fad7036ad4 qemu_conf: split out virQEMUDriverConfigLoadGlusterDebugEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:05 +01:00
Ján Tomko
632dab43b4 qemu_conf: split out virQEMUDriverConfigLoadSecurityEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:05 +01:00
Ján Tomko
6427aca725 qemu_conf: split out virQEMUDriverConfigLoadMemoryEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:05 +01:00
Ján Tomko
d447293893 qemu_conf: split out virQEMUDriverConfigLoadSWTPMEntry
Split out parts of the config parsing code to make
the parent function easier to read.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-18 12:55:05 +01:00
Peter Krempa
b70fb35d81 qemu: process: Use enum belonging to correct type
GCC was unhappy about comparison between two distinct enum types. Use
the correct value instead.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
2019-01-18 08:39:40 +01:00
Peter Krempa
4ab8447af7 qemu: blockjob: Add job name into the data
Currently the job name corresponds to the disk the job belongs to. For
jobs which will not correspond to disks we'll need to track the name
separately.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:51 +01:00
Peter Krempa
dfe11a705c qemu: blockjob: Convert qemuBlockJobSyncEndDisk to take job instead of disk
And rename it in accordance with the change.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
e5f704c971 qemu: migration: Don't call qemuBlockJobSyncEndDisk when block job has terminated
Now that the data is per-job, we don't really need to bother with
finishing the synchronous job handling if the job is already terminated.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
a54acc8570 qemu: Allocate diskPriv->blockjob only when there's a blockjob
Rather than storing the presence of the blockjob in a flag we can bind
together the lifecycle of the job with the lifecycle of the object which
is tracking the data for it.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
103a4245ae qemu: blockjob: Pass job into qemuBlockJobUpdateDisk and rename it
Instead of passing in the disk information, pass in the job and name the
function accordingly.

Few callers needed to be modified to have the job pointer handy.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
c257352797 qemu: blockjob: Consume new block job state in the processing function
The processing function modifies the job state so it should make sure
that the variable holding the new state is cleared properly and not the
caller. The caller should only deal with the job state and not the
transition that happened.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
8ca9fcec24 qemu: blockjob: Remove error propagation from qemuBlockJobUpdateDisk
The job error can be safely accessed in the job structure, so we don't
need to propagate it through qemuBlockJobUpdateDisk.

Drop the propagation and refactor any caller that pased non-NULL error.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
10c99feb05 qemu: migration: Extract reporting of disk migration error
The same message is reported in 3 distinct places. Move it out into a
single function.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
d1a44634ac qemu: blockjob: Track current state of blockjob
Add a field tracking the current state of job so that it can be queried
later. Until now the job state e.g. that the job is _READY for
finalizing was tracked only for mirror jobs. Add tracking of state for
all jobs.

Similarly to 'qemuBlockJobType' this maps the existing states of the
blockjob from virConnectDomainEventBlockJobStatus to
'qemuBlockJobState' so that we can track some internal states as well.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
728830be9b qemu: blockjob: Convert qemuBlockJobSyncBeginDisk to work with the job
Modify qemuBlockJobSyncBeginDisk to operate on qemuBlockt sJobDataPtr and
rename it accordingly.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
0ba9afc6b2 qemu: blockjob: Pass in job to qemuBlockJobEventProcessLegacy
Don't split out individual fields, just pass in the job.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
79b73251fb qemu: blockjob: Record job type when starting the job
We can properly track the job type when starting the job so that we
don't have to infer it later.

This patch also adds an enum of block job types specific to qemu
(qemuBlockjobType) which mirrors the public block job types
(virDomainBlockJobType) but allows for other types to be added later
which will not be public.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
f877ec1020 qemu: blockjob: Add reference to disk into struct qemuBlockJobData
Block jobs can also happen on objects which are not a disk at a given
point (e.g. the frontend was not hotplugged yet) and thus will be
eventually kept separately. Add a reference back to the disk for
blockjobs which do correspond to a disk.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
addb82bc5f qemu: blockjob: Drop unnecessary calls to qemuBlockJobSyncEndDisk
If the job wasn't started, we don't need to end the synchronous job. Add
a note and drop the unnecessary calls.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
e0c4d4fcf0 qemu: blockjob: Add functions for block job state control
Rather than directly modifying fields in the qemuBlockJobDataPtr
structure add a bunch of fields which allow to do the transitions.

This will help later when adding more complexity to the job handling.

APIs introduced in this patch are:

qemuBlockJobDiskNew - prepare for starting a new blockjob on a disk
qemuBlockJobDiskGetJob - get the block job data structure for a disk

For individual job state manipulation the following APIs are added:
qemuBlockJobStarted - Sets the job as started with qemu. Until that
                      the job can be cancelled without asking qemu.

qemuBlockJobStartupFinalize - finalize job startup. If the job was
                              started in qemu already, just releases
                              reference to the job object. Otherwise
                              clears everything as if the job was never
                              started.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
b44f1cd7d7 qemu: migration: Separate startup of disk mirror from migration logic
Extract the disk mirroring startup code from the loop into a separate
function to allow cleaner cleanup paths.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
b3e6a2ea3a qemu: blockjob: Clarify that job 'status' field contains new state
The field is used to note the state the job has transitioned to while
handling the blockjob state change event. Rename the field so that it's
obvious that this is the new state and not the general state of the
blockjob.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
4479bd4611 qemu: blockjob: Turn struct qemuBlockJobData into a virObject
Reference counting will simplify semantics of the lifecycle of the
object.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
466b78acb7 qemu: migration: Simplify cancellation of migration blockjobs
When cancelling job after a reconnect we can now use the disk block job
state rather than having to re-detect it in the migration code.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
c1a4fb04f9 qemu: driver: Remove block job status reprobing from qemuDomainBlockPivot
Now that we reprobe the status of blockjobs when reconnecting in
addition to handling job status events, the status reprobing can be
removed as we always track the correct status internally.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
9ed9124d0d qemu: process: refresh block jobs on reconnect
Block job state was widely untracked by libvirt across restarts which
was allowed by a stateless block job finishing handler which discarded
disk state and redetected it. This is undesirable since we'll need to
track more information for individual blockjobs due to -blockdev
integration requirements.

In case of legacy blockjobs we can recover whether the job is present at
reconnect time by querying qemu. Adding tracking whether a job is
present will allow simplification of the non-shared-storage cancellation
code.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
5918df1e62 qemu: migration: Properly note that non-shared-storage migration uses a blockjob
Internally we do a 'block-copy' to accomodate non-shared storage
migration but the code did not fill in that the block job was active on
the disk when starting the copy job. Since we handle block jobs finishes
regardless of having it registered it's not a problem but soon will
become one.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
232ab2f200 qemu: blockjob: Split out handling of completed jobs
qemuBlockJobEventProcessLegacy was getting too big. Remove handling of
completed jobs in a separate function.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
246303dc5b qemu: blockjob: Rename qemuBlockJobEventProcess to qemuBlockJobEventProcessLegacy
This will handle blockjob finalizing for the old approach so rename it
accordingly.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
2a1248badd qemu: process: Consolidate error paths in qemuProcessHandleBlockJob
'cleanup' label was accessed only from a jump to 'error'. Consolidate
everyting into 'cleanup'.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
89a877b312 qemu: Consolidate disk blockjob variables into a structure
Struct qemuDomainDiskPrivate was holding multiple variables connected to
a disk block job. Consolidate them into a new struct qemuBlockJobData.

This will also allow simpler extensions to the block job mechanisms.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
f5eadd1d92 qemu: blockjob: Remove header dependency on qemu_domain.h
The blockjob module uses 'qemuDomainAsyncJob' in it's public headers.
As I plan adding a new structure containing job data which will need to
be included in "qemu_domain.h" it's necessary to break the circular
dependency.

Convert 'qemuDomainAsyncJob' type to 'int' as it's an enum.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
f2bc59e48e qemu: blockjob: Rename public APIs
All the public APIs of the qemu_blockjob module operate on a 'disk'.
Since I'll be adding APIs which operate on a job later let's rename the
existing ones.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
359dc694f7 qemu: blockjob: Unexport qemuBlockJobEventProcess
The function is now only called locally. Some code movement was
necessary to avoid forward declarations.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
c3ec4b8d6a qemu: processBlockJobEvent: Use qemuBlockJobUpdate to process block job events
Replace use of qemuBlockJobEventProcess with the general helper. A small
tweak is required to pass in the 'type' and 'status' of the job via the
appropriate private data variables.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
b618a45b0f qemu: blockjob: Emit VIR_DOMAIN_EVENT_ID_BLOCK_JOB only for local disks
The event reports the disk path to identify the disk which makes sense
only for local disks. Additionally network backed disks like NBD don't
need to have a path so the callback would return NULL.

Report VIR_DOMAIN_EVENT_ID_BLOCK_JOB only for non-empty local disks.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Peter Krempa
56557b4898 qemu: blockjob: Extract emitting of libvirt events
Put the emitting of VIR_DOMAIN_EVENT_ID_BLOCK_JOB and
VIR_DOMAIN_EVENT_ID_BLOCK_JOB_2 into a separate function.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Ján Tomko
926cb125a4 qemu: fill out usage-specific TLS settings after parsing
Instead of copying the default default values upfront
and then wondering whether the user has given us a new default,
leave the per-usage TLS certdirs and secrets empty during
parsing and only fill them afterwards if they weren't provided
by the user.

This means that instead of looking whether the specific certdir
paths match the default default, the Validate function (which
is called in between parsing and setting the defaults) can error
out for missing directories if the value is present, because
it must've come from the user.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-17 15:53:20 +01:00
Ján Tomko
5ce02870c4 qemu.conf: fill out TLS verify attributes after parsing
Introduce a set of bool variables with the 'present' suffix
to track whether the value was actually specified.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-17 15:53:20 +01:00
Ján Tomko
10ee1270ff qemu: group swtpm entry in augeas file
They are meant to be together.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-17 15:53:20 +01:00
Ján Tomko
361f772f6f qemu: fix double space in augeas file
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-17 15:53:20 +01:00
Ján Tomko
900aae2c77 qemu: remove comments for qemuDomainSecret.*Destroy functions
These all contain the same copy and pasted '@disk' error,
and only repeat the list of arguments.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
2019-01-16 08:34:01 +01:00
Michal Privoznik
fc3990c7e6 qemu: Temporary disable owner remembering
Turns out, that there are few bugs that are not that trivial to
fix (e.g. around block jobs). Instead of rushing in not
thoroughly tested fixes disable the feature temporarily for the
release.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
ACKed-by: Peter Krempa <pkrempa@redhat.com>
2019-01-15 09:45:22 +01:00
John Ferlan
f30ac207ad qemu: Filter non SCSI hostdevs in qemuHostdevPrepareSCSIDevices
When commit 1d94b3e7 added code to walk the [n]hostdevs list looking
to add shared hostdevs, it should've filtered any hostdevs that were
not SCSI hostdev's.

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-11 08:52:10 -05:00
Michal Privoznik
2ebcff3a74 qemu: Don't enable seclabel remembering for session mode
The session daemon is unable to set XATTRs in 'trusted'
namespace because it doesn't run as privileged process.
Therefore, when creating the default qemu config enable
rememberOwner only when running as privileged process.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-10 16:15:42 +01:00
Ján Tomko
7cfd1fbb13 qemu: require reply from guest agent in qemuAgentGetInterfaces
Since its introduction in commit 0977b8aa07 (released in v1.2.14)
qemuAgentGetInterfaces calls qemuAgentCommand with needReply=false,
which allows qemuAgentCommand to return 0 even when it did not get
any reply from the agent.

Set needReply to true, since we dereference it right after.

This can be hit if libvirt is waiting for an event from the agent
(e.g. shutdown) and the agent cannot reply in time (e.g. due to
the guest being shut down), as reported in:
https://bugzilla.redhat.com/show_bug.cgi?id=1663051

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
2019-01-10 12:09:48 +01:00
Michal Privoznik
c39a0993dc src/qemu: Fix indentation in Makefile.inc.am
Three lines are a bit off there.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-01-09 17:56:09 +01:00
Michal Privoznik
f886271410 qemu: Use ULL instead of uint64_t for RDMA GID event
In the previous commit we are using uint64_t for storing subnet
prefix and interface id that qemu reports in
RDMA_GID_STATUS_CHANGED event. We also report them in some debug
messages. This poses a problem because uint64_t can be UL or ULL
depending on the host architecture and hence we wouldn't know
which format to use. Switch to ULL which is big enough and
doesn't suffer from the issue.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2019-01-09 11:31:58 +01:00
Yuval Shaia
ed357cef18 qemu: Process RDMA GID state change event
This event is emitted on the monitor when a GID table in pvrdma device
is modified and the change needs to be propagate to the backend RDMA
device's GID table.

The control over the RDMA device's GID table is done by updating the
device's Ethernet function addresses.
Usually the first GID entry is determine by the MAC address, the second
by the first IPv6 address and the third by the IPv4 address. Other
entries can be added by adding more IP addresses. The opposite is the
same, i.e. whenever an address is removed, the corresponding GID entry
is removed.

The process is done by the network and RDMA stacks. Whenever an address
is added the ib_core driver is notified and calls the device driver's
add_gid function which in turn update the device.

To support this in pvrdma device we need to hook into the create_bind
and destroy_bind HW commands triggered by pvrdma driver in guest.
Whenever a changed is made to the pvrdma device's GID table a special
QMP messages is sent to be processed by libvirt to update the address of
the backend Ethernet device.

Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2019-01-09 10:26:29 +01:00
Andrea Bolognani
5c7bfc6b53 src: Fix a few unmarked_diagnostics issues
These were not caught by our current regular expressions
but will be caught by the improved ones we're about to
introduce, so fix them ahead of time.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-08 17:18:31 +01:00
Luyao Zhong
87c87f41f6 qemu: Add qemu command-line to generate the nvdimm unarmed property
According to the result parsing from xml, add the unarmed property
into QEMU command line:

-device nvdimm,...[,unarmed=on]

Signed-off-by: Luyao Zhong <luyao.zhong@intel.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-02 09:00:34 -05:00
Luyao Zhong
82576d8f35 qemu: Add command-line to generate the nvdimm pmem property
According to the result parsing from xml, add pmem property
into QEMU command line:

-object memory-backend-file,...[,pmem=on]

Signed-off-by: Luyao Zhong <luyao.zhong@intel.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-02 09:00:34 -05:00
Luyao Zhong
1fdcaac3d3 qemu: Add command-line to generate the nvdimm align property
According to the result parsing from xml, add align property
into QEMU command line:

-object memory-backend-file,...[,align=xxx]

Signed-off-by: Luyao Zhong <luyao.zhong@intel.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-02 09:00:34 -05:00
Luyao Zhong
404766dbcc qemu: Introduce QEMU_CAPS_DEVICE_NVDIMM_UNARMED capability
This capability tracks if nvdimm has the unarmed attribute or not
for the nvdimm readonly xml attribute.

Signed-off-by: Luyao Zhong <luyao.zhong@intel.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-02 09:00:34 -05:00
Luyao Zhong
55b4fc78b6 qemu: Introduce QEMU_CAPS_OBJECT_MEMORY_FILE_PMEM capability
This capability tracks if memory-backend-file has the pmem
attribute or not.

Signed-off-by: Luyao Zhong <luyao.zhong@intel.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-02 09:00:34 -05:00
Luyao Zhong
e9b28cc9bc qemu: Introduce QEMU_CAPS_OBJECT_MEMORY_FILE_ALIGN capability
This capability tracks if memory-backend-file has the align
attribute or not.

Signed-off-by: Luyao Zhong <luyao.zhong@intel.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-02 09:00:34 -05:00
Erik Skultety
7dc31fe503 qemu: process: SEV: Relabel guest owner's SEV files created before start
Before launching a SEV guest we take the base64-encoded guest owner's
data specified in launchSecurity and create files with the same content
under /var/lib/libvirt/qemu/<domain>. The reason for this is that we
need to pass these files on to QEMU which then uses them to communicate
with the SEV firmware, except when it doesn't have permissions to open
those files since we don't relabel them.

https://bugzilla.redhat.com/show_bug.cgi?id=1658112

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Acked-by: Michal Privoznik <mprivozn@redhat.com>
2019-01-02 10:50:54 +01:00
Erik Skultety
2c4c7de159 qemu: process: SEV: Assume libDir to be the directory to create files in
Since SEV operates on a per domain basis, it's very likely that all
SEV launch-related data will be created under
/var/lib/libvirt/qemu/<domain_name>. Therefore, when calling into
qemuProcessSEVCreateFile we can assume @libDir as the directory prefix
rather than passing it explicitly.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Acked-by: Michal Privoznik <mprivozn@redhat.com>
2019-01-02 10:50:54 +01:00
Nikolay Shirokovskiy
c541177314 qemu: don't log error for missing optional storage sources on start
Because missing optional storage source is not error. The patch
address only local files. Fixing other cases is a bit ugly.
Below is example of error notice in log now:

error: virStorageFileReportBrokenChain:427 :
   Cannot access storage file '/path/to/missing/optional/disk':
  	No such file or directory

Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
2018-12-21 12:20:24 +03:00
Nikolay Shirokovskiy
318d807a0b qemu: don't log error for missing optional storage sources on stats
Every time we call all domain stats for inactive domain with
unavailable storage source we get error message in logs [1]. It's a bit noisy.
While it's arguable whether we need such message or not for mandatory
disks we would like not to see messages for optional disks. Let's
filter at least for cases of local files. Fixing other cases would
require passing flag down the stack to .backendInit of storage
which is ugly.

Stats for active domain are fine because we either drop disks
with unavailable sources or clean source which is handled
by virStorageSourceIsEmpty in qemuDomainGetStatsOneBlockFallback.

We have these logs for successful stats since 25aa7035d (version 1.2.15)
which in turn fixes 596a13713 (version 1.2.12 )which added substantial
stats for offline disks.

[1] error message example:
qemuOpenFileAs:3324 : Failed to open file '/path/to/optional/disk': No such file or directory

Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
2018-12-21 12:13:31 +03:00
Marc Hartmayer
91684829be qemu: Introduce caching whether /dev/kvm is accessible
Introduce caching whether /dev/kvm is usable as the QEMU user:QEMU
group. This reduces the overhead of the QEMU capabilities cache
lookup. Before this patch there were many fork() calls used for
checking whether /dev/kvm is accessible. Now we store the result
whether /dev/kvm is accessible or not and we only need to re-run the
virFileAccessibleAs check if the ctime of /dev/kvm has changed.

Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2018-12-19 15:50:57 +01:00
Michal Privoznik
e05d8e570b qemu.conf: Allow users to enable/disable label remembering
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-12-19 15:32:48 +01:00
Jiri Denemark
3f4914e03c qemu: Add support for postcopy-requests migration statistics
QEMU can report how many times during post-copy migration the domain
running on the destination host tried to access a page which has not
been migrated yet.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-12-17 16:16:30 +01:00
Daniel P. Berrangé
07c9d6601d qemu: use line breaks in command line args written to log
The QEMU command line arguments are very long and currently all written
on a single line to /var/log/libvirt/qemu/$GUEST.log. This introduces
logic to add line breaks after every env variable and "-" optional
argument, and every positional argument. This will create a clearer log
file, which will in turn present better in bug reports when people cut +
paste from the log into a bug comment.

An example log file entry now looks like this:

  2018-12-14 12:57:03.677+0000: starting up libvirt version: 5.0.0, qemu version: 3.0.0qemu-3.0.0-1.fc29, kernel: 4.19.5-300.fc29.x86_64, hostname: localhost.localdomain
  LC_ALL=C \
  PATH=/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin \
  HOME=/home/berrange \
  USER=berrange \
  LOGNAME=berrange \
  QEMU_AUDIO_DRV=none \
  /usr/bin/qemu-system-ppc64 \
  -name guest=guest,debug-threads=on \
  -S \
  -object secret,id=masterKey0,format=raw,file=/home/berrange/.config/libvirt/qemu/lib/domain-33-guest/master-key.aes \
  -machine pseries-2.10,accel=tcg,usb=off,dump-guest-core=off \
  -m 1024 \
  -realtime mlock=off \
  -smp 1,sockets=1,cores=1,threads=1 \
  -uuid c8a74977-ab18-41d0-ae3b-4041c7fffbcd \
  -display none \
  -no-user-config \
  -nodefaults \
  -chardev socket,id=charmonitor,fd=23,server,nowait \
  -mon chardev=charmonitor,id=monitor,mode=control \
  -rtc base=utc \
  -no-shutdown \
  -boot strict=on \
  -device qemu-xhci,id=usb,bus=pci.0,addr=0x1 \
  -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x2 \
  -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \
  -msg timestamp=on
  2018-12-14 12:57:03.730+0000: shutting down, reason=failed

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-17 15:02:11 +00:00
Daniel P. Berrangé
568a417224 Enforce a standard header file guard symbol name
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>
2018-12-14 10:47:13 +00:00
Daniel P. Berrangé
4cfd709021 Fix many mistakes & inconsistencies in header file layout
This introduces a syntax-check script that validates header files use a
common layout:

  /*
   ...copyright header...
   */
  <one blank line>
  #ifndef SYMBOL
  # define SYMBOL
  ....content....
  #endif /* SYMBOL */

For any file ending priv.h, before the #ifndef, we will require a
guard to prevent bogus imports:

  #ifndef SYMBOL_ALLOW
  # error ....
  #endif /* SYMBOL_ALLOW */
  <one blank line>

The many mistakes this script identifies are then fixed.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-14 10:46:53 +00:00
Daniel P. Berrangé
fe2bd0210e qemu: fix device name passed to error report
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-13 17:04:21 +00:00
Daniel P. Berrangé
600462834f Remove all Author(s): lines from source file headers
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.

In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.

With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to  find the
author of a particular bit of code.

This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.

The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.

Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-13 16:08:38 +00:00
John Ferlan
b183a75319 qemu: Add check for whether KVM nesting is enabled
Support for nested KVM is handled via a kernel module configuration
parameters values for kvm_intel, kvm_amd, kvm_hv (PPC), or kvm (s390).
While it's possible to fetch the kmod config values via virKModConfig,
unfortunately that is the static value and we need to get the
current/dynamic value from the kernel file system.

So this patch adds a new API virHostKVMSupportsNesting that will
search the 3 kernel modules to get the nesting value and check if
it is 'Y' (or 'y' just in case) to return a true/false whether
the KVM kernel supports nesting.

We need to do this in order to handle cases where adjustments to
the value are made after libvirtd is started to force a refetch of
the latest QEMU capabilities since the correct CPU settings need
to be made for a guest to add the "vmx=on" to/for the guest config.

Signed-off-by: John Ferlan <jferlan@redhat.com>
ACKed-by: Michal Privoznik <mprivozn@redhat.com>
2018-12-13 10:37:33 -05:00
Michal Privoznik
c658764dec qemu: Don't use -mem-prealloc among with .prealloc=yes
https://bugzilla.redhat.com/show_bug.cgi?id=1624223

There are two ways to request memory preallocation on cmd line:
-mem-prealloc and .prealloc attribute for a memory-backend-file.
However, as it turns out it's not safe to use both at the same
time. If -mem-prealloc is used then qemu will fully allocate the
memory (this is done by actually touching every page that has
been allocated). Then, if .prealloc=yes is specified,
mbind(flags = MPOL_MF_STRICT | MPOL_MF_MOVE) is called which:

a) has to (possibly) move the memory to a different NUMA node,
b) can have no effect when hugepages are in play (thus ignoring user
request to place memory on desired NUMA nodes).

Prefer -mem-prealloc as it is more backward compatible
compared to switching to "-numa node,memdev=  + -object
memory-backend-file".

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-12-13 09:55:38 +01:00
Michal Privoznik
9923584c62 qemuBuildMemoryBackendProps: Pass @priv instead of its individual members
So far we have two arguments that we are passing to
qemuBuildMemoryBackendProps() and that are taken from domain
private data: @qemuCaps and @autoNodeset. In the next commit I
will use one more item from there. Therefore, instead of having
it as yet another argument to the function, pass pointer to the
private data object.

There is one change in qemuDomainAttachMemory() where previously
@autoNodeset was NULL but now is priv->autoNodeset (which may be
set). This is safe to do as @autoNodeset is advisory only.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-12-13 09:51:45 +01:00
Erik Skultety
414c51b7a1 qemu: domain: gfx: Fix shadowing of a function argument in validation
Since the code was never run, it would have been very hard to spot this
mistake, especially since the compiler can't really warn about it.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-12-12 15:12:35 +01:00
Nikolay Shirokovskiy
067aad26be qemu: disable external snapshot of readonly disk
Disable external snapshot of a readonly disk for domains as
this operation is not very useful. Such a snapshot is not
possible for active domains but the error message from QEMU
is more cryptic:

     error: internal error: unable to execute QEMU command 'transaction':
                         Could not create file: Permission denied

This error at least makes the error more understandable for
active domains and disallows for inactive domains as well.

Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-12-11 10:58:34 +03:00
John Ferlan
61d1253364 qemu: Don't fail stats collection due to IOThread capability
Commit 212dc9286 made a generic qemuDomainGetIOThreadsMon which
would fail if the QEMU_CAPS_OBJECT_IOTHREAD didn't exist. Then
commit d1eac927 used that helper for the collection of all domain
stats. However, if the capability doesn't exist, then the entire
stats collection fails. Since the IOThread stats were meant to be
if available only, thus rather than failing if the capability
doesn't exist, let's just not collect the stats. Restore the caps
failure logic for qemuDomainGetIOThreadsLive.

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-12-06 12:29:03 -05:00
John Ferlan
e1fc7ec081 qemu: Save qemuDomainGetStats error
During qemuConnectGetAllDomainStats if qemuDomainGetStats causes
a failure, then when collecting more than one domain's worth of
statistics the loop in virDomainStatsRecordListFree would call
virDomainFree which would call virResetLastError effectively wiping
out the reason we failed leaving the caller with no idea why the
collection failed.

To fix this, let's Preserve the error and Restore it prior to return
so that a caller such as 'virsh domstats' doesn't get the generic
"error: An error occurred, but the cause is unknown".

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-12-06 11:38:07 -05:00