Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Add dbusVMStates to keep a list of dbus-vmstate objects needed for
migration. They are populated on the command line during start or
qemuDBusVMStateAdd/Remove() will hotplug them as needed.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Since libvirt stores the backing chain into the XML in a nested way it
is the prime possibility to hit libxml2's parsing limit of 256 layers.

Introduce code which will crawl the backing chain and verify that it's
not too deep. The maximum nesting is set to 200 layers so that there's
still some space left for additional properties or nesting into snapshot
XMLs.

The check is applied to all disk use cases (starting, hotplug, media
change) as well as block copy which changes image and snapshots.

We simply report an error and refuse the operation.

Without this check a restart of libvirtd would result in the status XML
failing to be parsed and thus losing the VM.

https://bugzilla.redhat.com/show_bug.cgi?id=1524278Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

In addition to the data that libvirt needs and extracts internally,
copy and store the whole 'props' JSON sub-object of the data returned by
query-hotpluggable-cpus for future use.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

Now that virDomainXMLNamespace matches virXMLNamespace,
we no longer need to keep both around.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NJiri Denemark <jdenemar@redhat.com>

Since qemuDomainDefPostParse callback requires qemuCaps, we need to make
sure it gets the capabilities stored in the domain's private data if the
domain is running. Passing NULL may cause QEMU capabilities probing to
be triggered in case QEMU binary changed in the meantime. When this
happens while a running domain object is locked, QMP event delivered to
the domain before QEMU capabilities probing finishes will deadlock the
event loop.

This patch fixes all paths leading to qemuDomainDefFormatBufInternal.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Since qemuDomainDefPostParse callback requires qemuCaps, we need to make
sure it gets the capabilities stored in the domain's private data if the
domain is running. Passing NULL may cause QEMU capabilities probing to
be triggered in case QEMU binary changed in the meantime. When this
happens while a running domain object is locked, QMP event delivered to
the domain before QEMU capabilities probing finishes will deadlock the
event loop.

This patch fixes all paths leading to qemuDomainDefCopy.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Qemu bitmap operations require knowing the node name associated with
the format layer (the qcow2 file); as upcoming patches will be
grabbing that information frequently, make a helper function to access
it.

Another potential benefit of this function is that we have a single
place where we could insert a QMP node-name scraping call if we don't
currently know the node name, when -blockdev is not supported;
however, the goal is that we hopefully don't ever have to do that
because we instead scrape node names only at the point where they
change.
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

A lot of this work heavily copies from the existing snapshot APIs.
What's more, this patch is (intentionally) very similar to the
checkpoint code just added in the test driver, to the point that qemu
checkpoints are not fully usable in this patch, but it at least
bisects and builds cleanly.  The separation between patches is done
because the grunt work of saving and restoring XML and tracking
relations between checkpoints is common to the test driver, while the
later patch adding integration with QMP is specific to qemu.

Also note that the interlocking to prevent checkpoints and snapshots
from existing at the same time will be a separate patch, to make it
easier to revert that restriction when we finally round out the design
for supporting interaction between the two concepts.
Signed-off-by: NEric Blake <eblake@redhat.com>

The PR manager is a property of the format layer in qemu so we need to
be able to track it also in the chains of orphaned block jobs.

Add a helper for qemu to look also into the blockjob state.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Add support for handling the event either synchronously or
asynchronously using the event thread.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Block jobs currently belong to disks only so we can look up the block
job data for them in the corresponding disks. This won't be the case
when using blockdev as certain jobs don't even correspond to a disk and
most of them can run on a part of the backing chain.

Add a global table of blockjobs which can be used to look up the data
for the blockjobs when the job events need to be processed.

The table is a hash table organized by job name and has a reference to
the job. New and running jobs will later be added to this table.
Reference counting will allow to reap job state for synchronous callers.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Similarly to qemuDomainSaveStatus add a helper to save the config XML
named qemuDomainSaveConfig.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Rename qemuDomainObjSaveJob and create a wrapper for it which does not
require 'driver' to be passed and export it so that other palces can
easily save the status XML without having to invoke virDomainSaveStatus
which has unpleasing parameters.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

There are some paths (e.g. /dev/vfio/vfio or /dev/mapper/control)
which are defined in qemu_domain.c and then in qemu_cgroup.c
again. This is suboptimal. Let's move paths into qemu_domain.h and
drop duplicate definitions.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

Similarly how we allow adding arbitrary command line arguments and
environment variables this patch introduces the ability to control
libvirt's perception of the qemu process by tweaking the capability bits
for testing purposes.

The idea is to allow developers and users either test a new feature by
enabling it early or disabling it to see whether it introduced
regressions.

This feature is not meant for production use though, so users should
handle it with care.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

qemu_conf.c deals with the configuration file. Better fit for the
structure and freeing function will be qemu_domain.c where the rest of
the namespace parsing/formatting stuff resides.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

If we have a monitor, it is a JSON monitor.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Acked-by: NPeter Krempa <pkrempa@redhat.com>

Signed-off-by: NJonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

Introduce qemuDomainStorageSourceChainAccess(Allow|Revoke) as entry
points to qemuDomainStorageSourceChainAccessPrepare for symmetry with
the functions for single backing chain elements.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Move it to qemu_domain.c and call it
qemuDomainStorageSourceChainAccessPrepare.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Use qemuDomainStorageSourceAccess(Allow|Revoke) instead.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

virutil.(c|h) is a very gross collection of random code. Remove the enum
handlers from there so we can limit the scope where virtutil.h is used.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Map is based on existing cases in code where we send suspended
event after changing domain state to paused.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>

Similar to commit [1] which saves and passes the running reason to
the RESUME event handler, during qemuProcessStopCPUs let's save and pass
the pause reason in the domain private data so that the STOP event
handler can use it.

[1] 5dab984e : qemu: Pass running reason to RESUME event handler
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>

It always returns true.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Use the common base class virDomainMoment for iterator callbacks
related to snapshots from the qemu code, so that when checkpoint
operations are introduced, they can share the same callbacks.

Simplify the code for qemuDomainSnapshotCurrent by better utilizing
virDomainMoment helpers.
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

Now that the core of SnapshotObj is agnostic to snapshots and can be
shared with upcoming checkpoint code, it is time to rename the struct
and the functions specific to list operations. A later patch will
shuffle which file holds the common code. This is a fairly mechanical
patch.
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1623389

If a device is detached twice from the same domain the following
race condition may happen:

1) The first DetachDevice() call will issue "device_del" on qemu
monitor, but since the DEVICE_DELETED event did not arrive in
time, the API ends claiming "Device detach request sent
successfully".

2) The second DetachDevice() therefore still find the device in
the domain and thus proceeds to detaching it again. It calls
EnterMonitor() and qemuMonitorSend() trying to issue "device_del"
command again. This gets both domain lock and monitor lock
released.

3) At this point, qemu sends us the DEVICE_DELETED event which is
going to be handled by the event loop which ends up calling
qemuDomainSignalDeviceRemoval() to determine who is going to
remove the device from domain definition. Whether it is the
caller that marked the device for removal or whether it is going
to be the event processing thread.

4) Because the device was marked for removal,
qemuDomainSignalDeviceRemoval() returns true, which means the
event is to be processed by the thread that has marked the device
for removal (and is currently still trying to issue "device_del"
command)

5) The thread finally issues the "device_del" command, which
fails (obviously) and therefore it calls
qemuDomainResetDeviceRemoval() to reset the device marking and
quits immediately after, NOT removing any device from the domain
definition.

At this point, the device is still present in the domain
definition but doesn't exist in qemu anymore. Worse, there is no
way to remove it from the domain definition.

Solution is to note down that we've seen the event and if the
second "device_del" fails, not take it as a failure but carry on
with the usual execution.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>

Move the code that (possibly) generates filename of NVRAM VAR
store into a single function so that it can be re-used later.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NLaszlo Ersek <lersek@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

qemuDomainSnapshotWriteMetadata does not modify the directory name,
and making it const-correct aids in writing an upcoming patch.
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

The function operates on a virDomainDef and is not tied to
device address assignment in any way, so it makes more sense
for it to live along with qemuDomainIs*() and the like.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>

Ideally we'd make all of them static, but there are a few
cases where we don't have a virDomainDef instance handy and
so they are the only option.

For the few ones we're forced to keep exporting, document
through comments that the alternative is preferred.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>

We want the signatures to be consistent, and also we're
going to start using the additional parameter next.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>

Make sure related functions, eg. all qemuDomainIs*(), are
close together instead of being sprinkled throughout both
the header and implementation file, and also that all
qemuDomainMachine*() functions are declared first since
we're going to make a bunch of them static later on.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>

Remove the uneeded attribute and return value.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>), and we have a mix of semicolon and
non-semicolon usage through the code. Let's standardize on using
a semicolon for VIR_ENUM_DECL calls.

Drop the semicolon from the final statement of the macro, so
the compiler will require callers to add a semicolon.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

The virDomainDeviceInfo parameter is a large struct so it is preferrable
to pass it by reference instead of by value.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

When we need to detect a chain for a image which will become the new
source for a disk (e.g. after a disk media change or a blockjob) we'd
need to replace disk->src temporarily to do so.

Move the 'disksrc' temporary variable to an argument and adjust callers.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>