libxl events are delivered to libvirt via the libxlDomainEventHandler
callback registered with libxl. Documenation in
$xensrc/tools/libxl/libxl_event.h states that the callback "may occur
on any thread in which the application calls libxl". This can result
in deadlock since many of the libvirt callees of libxl hold a lock on
the virDomainObj they are working on. When the callback is invoked, it
attempts to find a virDomainObj corresponding to the domain ID provided
by libxl. Searching the domain obj list results in locking each obj
before checking if it is active, and its ID equals the requested ID.
Deadlock is possible when attempting to lock an obj that is already
locked further up the call stack. Indeed, Max Ustermann reported an
instance of this deadlock

https://www.redhat.com/archives/libvir-list/2015-November/msg00130.html

Guido Rossmueller also recently stumbled across it

https://www.redhat.com/archives/libvir-list/2016-September/msg00287.html

Fix the deadlock by moving the lookup of virDomainObj to the
libxlDomainShutdownThread. After this patch, libxl events are
enqueued on the libvirt side and processed by dedicated thread,
avoiding the described deadlock.
Reported-by: NMax Ustermann <ustermann78@web.de>
Reported-by: NGuido Rossmueller <Guido.Rossmueller@gdata.de>

Just like virDomainDefPostParseCallback has gained new
parseOpaque argument, we need to follow the logic with
virDomainDeviceDefPostParse.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

We want to pass the proper opaque pointer instead of NULL to
virDomainDefParseString.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

We want to pass the proper opaque pointer instead of NULL to
virDomainDefParse and subsequently virDomainDefParseNode too.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Some callers might want to pass yet another pointer to opaque
data to post parse callbacks. The driver generic one is not
enough because two threads executing post parse callback might
want to see different data (e.g. domain object pointer that
domain def belongs to).
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

The code for replacing domain's transient definition with the persistent
one is repeated in several places and we'll need to add one more. Let's
make a nice helper for it.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Add support for multi serial devices, after this patch virsh can be used to
connect different serial devices of running domains. E.g.
vish # console <xxx> --devname serial<xxx>

Note:
This depends on a xen/libxl bug fix to have libxl_console_get_tty(...) correctly
returning the tty path (as opposed to always returning the first one).
[0] https://lists.xen.org/archives/html/xen-devel/2016-08/msg00438.htmlSigned-off-by: NBob Liu <bob.liu@oracle.com>

Commit id '7d3b2eb5' missed a closing parenthesis on the ignore_value
macro, causing the failure

Introduce libxl hook and use it for start, prepare, started,
stop, stopped, migrate events.

The migrate hook will affect the migrated guest definition. Allow
these domains be marked as tainted in the libxl driver.

All the same information was already there, just in slightly different
places in the virDomainNetDef.

When domXML contains only <console type='pty'> and no corresponding
<serial>, the console is "stolen" [1] and used as the first <serial>
device. When this "stolen" console is accessed from the libxl driver
(in libxlConsoleCallback and libxlDomainOpenConsole), check if the
targetType is VIR_DOMAIN_CHR_CONSOLE_TARGET_TYPE_SERIAL, and use the
"stolen" device in def->serials[0] instead. Prior to this change,
creating a domain with input XML containing only a <console> device
and subsequently attempting to access its console with
'virsh console' would fail

error: internal error: character device <null> is not using a PTY

[1] See comments associated with virDomainDefAddConsoleCompat() in
    $LIBVIRT-SRC/src/conf/domain_conf.c:

Support creating guest with USB host device in config file.
Currently libxl only supports xen PV guest, and only supports
specifying USB host device by 'bus number' and 'device number',
for example:

    <hostdev mode='subsystem' type='usb' managed='no'>
      <source>
        <address bus='1' device='3'/>
      </source>
    </hostdev>
Signed-off-by: NChunyan Liu <cyliu@suse.com>
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

Move capabilities code out of libxl_conf.{ch} and into new
libxl_capabilities.{ch} files.
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

In libxl driver we do virObjectRef in libxlDomainObjBeginJob,
If virCondWaitUntil failed, it goes to error, do virObjectUnref,
There's a chance that someone undefine the vm at the same time,
and refs unref to zero, vm is freed in libxlDomainObjBeginJob.
But the vm outside function is not Null, we do virObjectUnlock(vm).
That's how we overwrite the vm memory after it's freed. I fix it.
Signed-off-by: NWang Yufei <james.wangyufei@huawei.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Until now we weren't able to add checks that would reject configuration
once accepted by the parser. This patch adds a new callback and
infrastructure to add such checks. In this patch all the places where
rejecting a now-invalid configuration wouldn't be a good idea are marked
with a new parser flag.

Remove the live attribute and mark the definition as transient
whether the domain is runing or not.

There were only two callers left calling with live=false:
* testDomainStartState, where the domain already is active
  because we assigned vm->def->id just a few lines above the call
* virDomainObjGetPersistentDef, which now only calls
  virDomainObjSetDefTransient for an active domain

Xen only supports network-based disks with the qemu (aka qdisk) driver.
Set the driverName to 'qemu' in libxlDomainDeviceDefPostParse() if
not already set. When starting a domain with network-based disks,
ensure the driverName is 'qemu'.

Resolves: https://bugzilla.opensuse.org/show_bug.cgi?id=981094

Convert to virGetLastErrorMessage() in the rest of the code

Xen 4.6 introduced a new migration stream commonly referred to as
"migration V2". Xen 4.6 and newer always produce this new stream,
whereas Xen 4.5 and older always produce the legacy stream.
Support for migration stream V2 can be detected at build time with
LIBXL_HAVE_SRM_V2 from libxl.h. The legacy and V2 streams are not
compatible, but a V2 host can accept and convert a legacy stream.

Commit e7440656 changed the libxl driver to use the lowest libxl
API version possible (version 0x040200) to ensure the driver
builds against older Xen releases. The old 4.2 restore API does
not support specifying a stream version and assumes a legacy
stream, even if the incoming stream is migration V2. Thinking it
has been given a legacy stream, libxl will fail to convert an
incoming stream that is already V2, which causes the entire
restore operation to fail. Xen's libvirt-related OSSTest has been
failing since commit e7440656 landed in libvirt.git master. One
of the more recent failures can be seen here

http://lists.xenproject.org/archives/html/xen-devel/2016-05/msg00071.html

This patch changes the call to libxl_domain_create_restore() to
include the stream version if LIBXL_HAVE_SRM_V2 is defined. The
version field of the libxlSavefileHeader struct is also updated
to '2' when LIBXL_HAVE_SRM_V2 is defined, ensuring the stream
version in the header matches the actual stream version produced
by Xen. Along with bumping the libxl API requirement to 0x040400,
this patch fixes save/restore on a migration V2 Xen host.

Oddly, migration has never used the libxlSavefileHeader. It
handles passing configuration in the Begin and Prepare phases,
and then calls libxl directly to transfer domain state/memory
in the Perform phase. A subsequent patch will add stream
version handling in the Begin and Prepare phase handshaking,
which will fix the migration related OSSTest failures.
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

In LIBXL_API_VERSION 0x040400, the libxl_domain_create_restore API
gained a parameter for specifying restore parameters. Switch to
using version 0x040400, which will be useful in a subsequent commit
to specify the Xen migration stream version when restoring.
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

To ensure the libvirt libxl driver will build with future versions
of Xen where the libxl API may change in incompatible ways,
explicitly use LIBXL_API_VERSION 0x040200. The libxl driver
does use new libxl APIs that have been added since Xen 4.2, but
currently it does not make use of any changes made to existing
APIs such as libxl_domain_create_restore or libxl_set_vcpuaffinity.
The version can be bumped if/when the libxl driver consumes the
changed APIs.

Further details can be found in the following discussion thread

https://www.redhat.com/archives/libvir-list/2016-April/msg00178.htmlSigned-off-by: NJim Fehlig <jfehlig@suse.com>

Add codes to support creating domain with network defition of assigning
SRIOV VF from a pool.
Signed-off-by: NChunyan Liu <cyliu@suse.com>
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

In the latest libxenlight code, libxl_domain_create_restore accepts a
new argument. Update libvirt's libxl driver for that. Use the macro
provided by libxenlight to detect which version should be used.

The new parameter (send_back_fd) is set to -1 because libvirt provides
no such fd.
Signed-off-by: NWei Liu <wei.liu2@citrix.com>
Message-id: 1459866012-27081-1-git-send-email-wei.liu2@citrix.com

Remove disabling domain death events from libxlDomainStart error
path. The domain death event is already disabled in libxlDomainCleanup.
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

libxlDomainStart allocates and reserves resources that were not
being released in error paths. libxlDomainCleanup already handles
the job of releasing resources, and libxlDomainStart should call
it when encountering a failure.

Change the error handling logic to call libxlDomainCleanup on
failure. This includes acquiring the lease sooner and allowing
it to be released in libxlDomainCleanup on failure, similar to
the way other resources are reclaimed. With the lease now
released in libxlDomainCleanup, the release_dom label can be
renamed to cleanup_dom to better reflect its changed semantics.
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

Rename cleanup_dom label to destroy_dom, which better describes what
it does.
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

Introduce a helper to check supported device and domain config and move
the memory hotplug checks to it.

The advantage of this approach is that by default all new features are
considered unsupported by all hypervisors unless specifically changed
rather than the previous approach where every hypervisor would need to
declare that a given feature is unsupported.

Introduce support for domainInterfaceStats API call for querying
network interface statistics. Consequently it also enables the use of
`virsh domifstat <dom> <interface name>` command plus seeing the
interfaces names instead of "-" when doing `virsh domiflist <dom>`.

After successful guest creation we fill the network interfaces names
based on domain, device id and append suffix if it's emulated in the
following form: vif<domid>.<devid>[-emu].  We extract the network
interfaces info from the libxl_domain_config object in
libxlDomainCreateIfaceNames() to generate ifname. On domain cleanup we
also clear ifname, in case it was set by libvirt (i.e. being prefixed
with "vif"). We also skip these two steps in case the name of the
interface was manually inserted by the administrator. Since the
introduction of netprefix (commit a040ba9e), ifnames with a registered
prefix will be freed on virDomain{Obj,Def}Format*, thus eliminating
the migration issues observed with the reverted commit d2e5538b whereas
source and destination would have the same ifname.

For getting the interface statistics we resort to virNetInterfaceStats
and let libvirt handle the platform specific nits. Note that the
latter is not yet supported in FreeBSD.
Signed-off-by: NJoao Martins <joao.m.martins@oracle.com>

Signed-off-by: NChunyan Liu <cyliu@suse.com>

Now with the new struct the data can be stored in a much saner place.

This step can be omitted, so that drivers can decide what to do when the
user requests to use default vcpu pinning.

The virDomainObjFormat and virDomainSaveStatus methods
both call into virDomainDefFormat, so should be providing
a non-NULL virCapsPtr instance.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

And use the newly added caps->host.netprefix (if it exists) for
interface names that match the autogenerated target names.
Signed-off-by: NJoao Martins <joao.m.martins@oracle.com>

The current code was a little bit odd.  At first we've removed all
possible implicit input devices from domain definition to add them later
back if there was any graphics device defined while parsing XML
description.  That's not all, while formating domain definition to XML
description we at first ignore any input devices with bus different to
USB and VIRTIO and few lines later we add implicit input devices to XML.

This seems to me as a lot of code for nothing.  This patch may look
to be more complicated than original approach, but this is a preferred
way to modify/add driver specific stuff only in those drivers and not
deal with them in common parsing/formating functions.

The update is to add those implicit input devices into config XML to
follow the real HW configuration visible by guest OS.

There was also inconsistence between our behavior and QEMU's in the way,
that in QEMU there is no way how to disable those implicit input devices
for x86 architecture and they are available always, even without graphics
device.  This applies also to XEN hypervisor.  VZ driver already does its
part by putting correct implicit devices into live XML.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

This way both Domain and Device PostParse functions can act based on the
flags.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Introduce support for domainGetJobInfo to get info about the
ongoing job. If the job is active it will update the
timeElapsed which is computed with the "started" field added to
struct libxlDomainJobObj.  For now we support just the very basic
info and all jobs have VIR_DOMAIN_JOB_UNBOUNDED (i.e. no completion
time estimation) plus timeElapsed computed.

Openstack Kilo uses the Job API to monitor live-migration
progress which is currently nonexistent in libxl driver and
therefore leads to a crash in the nova compute node. Right
now, migration doesn't use jobs in the source node and will
return VIR_DOMAIN_JOB_NONE. Though nova handles this case and
will migrate it properly instead of crashing.
Signed-off-by: NJoao Martins <joao.m.martins@oracle.com>

We should make a copy of current definition to preserve a persistent
definition, because we later update the definition with live changes.
The live definition is discarded on domain shutdown and replaced by the
copy we make before starting the domain.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

This reverts commit d2e5538b.

A migration regression was introduced by this commit. When migrating
a domain, its active XML is sent to the destination libvirtd, where
it is parsed as inactive XML. d2e5538b copied the libxl generated
interface name into the active config, which was being passed to the
migration destination and being parsed into inactive config. Attempting
to start the config could result in failure if an interface with the
same generated name already exists.

The qemu driver behaves similarly, but the parser contains a hack to
skip interface names starting with 'vnet' when parsing inactive XML.
We could extend the hack to skip names starting with 'vif' too, but a
better fix would be to expose these hypervisor-specific interface name
prefixes in capabilities. See the following discussion thread for more
details

https://www.redhat.com/archives/libvir-list/2015-December/msg00262.html

For the pending 1.3.0 release, it is best to revert d2e5538b. It can
be added again post release, after moving the prefix to capabilities.