Currently the virQEMUDriverPtr struct contains an wide variety
of data with varying access needs. Move all the static config
data into a dedicated virQEMUDriverConfigPtr object. The only
locking requirement is to hold the driver lock, while obtaining
an instance of virQEMUDriverConfigPtr. Once a reference is held
on the config object, it can be used completely lockless since
it is immutable.
NB, not all APIs correctly hold the driver lock while getting
a reference to the config object in this patch. This is safe
for now since the config is never updated on the fly. Later
patches will address this fully.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virDomainObj, qemuAgent, qemuMonitor, lxcMonitor classes
all require a mutex, so can be switched to use virObjectLockable
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The functionality provided in virchrdev.c (previously virconsole.c) is
applicable to other types of character devices besides consoles, such
as channels. This patch is just code motion, renaming things such as
"console" or "pty", instead using more general terms such as
"character device" or "device path".
Replace the following names
* struct qemu_snap_remove with virQEMUSnapRemovePtr
* struct qemu_snap_reparent with virQEMUSnapReparentPtr
* struct qemu_save_header with virQEMUSaveHeaderPtr
* enum qemu_save_formats with virQEMUSaveFormat
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Remove the obsolete 'qemud' naming prefix and underscore
based type name. Introduce virQEMUDriverPtr as the replacement,
in common with LXC driver naming style
I have been testing libvirt v1.0.0 for deployment within my
organization, and in the process discovered what appears to be a bug
that breaks virsh attach-device, when attaching an RBD volume to an
instance. First, here is the error presented, with v1.0.0 (this worked
in v0.10.2):
[root@host ~]# virsh attach-device W5APQ8 G84VV1.xml
error: Failed to attach device from G84VV1.xml
error: cannot open file 'dc3-1-test/G84VV1': No such file or directory
Using git bisect, I narrowed the problem down to this as the first
commit to break this setup:
4d34c92947 is the first bad commit
Currently, if user calls virDomainAbortJob we just issue
'migrate_cancel' and hope for the best. However, if user calls
the API in wrong phase when migration hasn't been started yet
(perform phase) the cancel request is just ignored. With this
patch, the request is remembered and as soon as perform phase
starts, migration is cancelled.
The new external system checkpoints will require an async job while the
snapshot is taken. This patch adds QEMU_ASYNC_JOB_SNAPSHOT to track this
job type.
In the XML warning, we print a virsh command line that can be used to
edit that XML. This patch prints UUIDs if the entity name contains
special characters (like shell metacharacters, or "--" that would break
parsing of the XML comment). If the entity doesn't have a UUID, just
print the virsh command that can be used to edit it.
Technically, we should not be re-probing any file that qemu might
be currently writing to. As such, we should cache the backing
file chain prior to starting qemu. This patch adds the cache,
but does not use it until the next patch.
Ultimately, we want to also store the chain in domain XML, so that
it is remembered across libvirtd restarts, and so that the only
kosher way to modify the backing chain of an offline domain will be
through libvirt API calls, but we aren't there yet. So for now, we
merely invalidate the cache any time we do a live operation that
alters the chain (block-pull, block-commit, external disk snapshot),
as well as tear down the cache when the domain is not running.
* src/conf/domain_conf.h (_virDomainDiskDef): New field.
* src/conf/domain_conf.c (virDomainDiskDefFree): Clean new field.
* src/qemu/qemu_domain.h (qemuDomainDetermineDiskChain): New
prototype.
* src/qemu/qemu_domain.c (qemuDomainDetermineDiskChain): New
function.
* src/qemu/qemu_driver.c (qemuDomainAttachDeviceDiskLive)
(qemuDomainChangeDiskMediaLive): Pre-populate chain.
(qemuDomainSnapshotCreateSingleDiskActive): Uncache chain before
snapshot.
* src/qemu/qemu_process.c (qemuProcessHandleBlockJob): Update
chain after block pull.
When libvirt cannot find a suitable CPU model for host CPU (easily
reproducible by running libvirt in a guest), it would not provide CPU
topology in capabilities XML either. Even though CPU topology is known
and can be queried by virNodeGetInfo. With this patch, CPU topology will
always be provided in capabilities XML regardless on the presence of CPU
model.
The comment stated that you may call qemuDomainObjBeginJobWithDriver
without passing qemud_driver to signal it's not locked.
qemuDomainObjBeginJobWithDriver still accesses the qemud_driver
structure and the lock singaling is done through a separate parameter.
Using VIR_DOMAIN_XML_MIGRATABLE flag, one can request domain's XML
configuration that is suitable for migration or save/restore. Such XML
may contain extra run-time stuff internal to libvirt and some default
configuration may be removed for better compatibility of the XML with
older libvirt releases.
This flag may serve as an easy way to get the XML that can be passed
(after desired modifications) to APIs that accept custom XMLs, such as
virDomainMigrate{,ToURI}2 or virDomainSaveFlags.
SELinux wants all log files opened with O_APPEND. When
running non-root though, libvirtd likes to use O_TRUNC
to avoid log files growing in size indefinitely. Instead
of using O_TRUNC though, we can use O_APPEND and then
call ftruncate() which keeps SELinux happier.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.
* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/; If/. If/
The current qemu capabilities are stored in a virBitmapPtr
object, whose type is exposed to callers. We want to store
more data besides just the flags, so we need to move to a
struct type. This object will also need to be reference
counted, since we'll be maintaining a cache of data per
binary. This change introduces a 'qemuCapsPtr' virObject
class. Most of the change is just renaming types and
variables in all the callers
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
We were failing to react to allocation failure when initializing
a snapshot object list. Changing things to store a pointer
instead of a complete object adds one more possible point of
allocation failure, but at the same time, will make it easier to
react to failure now, as well as making it easier for a future
patch to split all virDomainSnapshotPtr handling into a separate
file, as I continue to add even more snapshot code.
Luckily, there was only one client outside of domain_conf.c that
was actually peeking inside the object, and a new wrapper function
was easy.
* src/conf/domain_conf.h (_virDomainObj): Use a pointer.
(virDomainSnapshotObjListInit): Rename.
(virDomainSnapshotObjListFree, virDomainSnapshotForEach): New
declarations.
(_virDomainSnapshotObjList): Move definitions...
* src/conf/domain_conf.c: ...here.
(virDomainSnapshotObjListInit, virDomainSnapshotObjListDeinit):
Rename...
(virDomainSnapshotObjListNew, virDomainSnapshotObjListFree): ...to
these.
(virDomainSnapshotForEach): New function.
(virDomainObjDispose, virDomainListPopulate): Adjust callers.
* src/qemu/qemu_domain.c (qemuDomainSnapshotDiscard)
(qemuDomainSnapshotDiscardAllMetadata): Likewise.
* src/qemu/qemu_migration.c (qemuMigrationIsAllowed): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotLoad)
(qemuDomainUndefineFlags, qemuDomainSnapshotCreateXML)
(qemuDomainSnapshotListNames, qemuDomainSnapshotNum)
(qemuDomainListAllSnapshots)
(qemuDomainSnapshotListChildrenNames)
(qemuDomainSnapshotNumChildren)
(qemuDomainSnapshotListAllChildren)
(qemuDomainSnapshotLookupByName, qemuDomainSnapshotGetParent)
(qemuDomainSnapshotGetXMLDesc, qemuDomainSnapshotIsCurrent)
(qemuDomainSnapshotHasMetadata, qemuDomainRevertToSnapshot)
(qemuDomainSnapshotDelete): Likewise.
* src/libvirt_private.syms (domain_conf.h): Export new function.
Previously, qemu did not respond to monitor commands during migration if
the limit was too high. This prevented us from raising the limit
earlier. The qemu issue seems to be fixed (according to my testing) and
we may remove the 32Mb/s limit.
Switch virDomainObjPtr to use the virObject APIs for reference
counting. The main change is that virObjectUnref does not return
the reference count, merely a bool indicating whether the object
still has any refs left. Checking the return value is also not
mandatory.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)
You should have received a copy of the GNU General Public License
along with Foobar. If not, see <http://www.gnu.org/licenses/>.
This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').
Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:
src/security/security_selinux.h
src/security/security_driver.h
src/security/security_selinux.c
src/security/security_apparmor.h
src/security/security_apparmor.c
src/security/security_driver.c
When we added the default USB controller into domain XML, we efficiently
broke migration to older versions of libvirt that didn't support USB
controllers at all (0.9.4 and earlier) even for domains that don't use
anything that the older libvirt can't provide. We still want to present
the default USB controller in any XML seen by a user/app but we can
safely remove it from the domain XML used during migration. If we are
migrating to a new enough libvirt, it will add the controller XML back,
while older libvirt won't be confused with it although it will still
tell qemu to create the controller.
Similar approach can be used in the future whenever we find out we
always enabled some kind of device without properly advertising it in
domain XML.
In case an API fails with "cannot acquire state change lock", searching
for the API that possibly forgot to end its job is not always easy.
Let's keep track of the job owner and print it out for easier
identification.
As reported by Daniel Berrangé, we have a huge performance regression
for virDomainGetInfo() due to the change which makes virDomainEndJob()
save the XML status file every time it is called. Previous to that
change, 2000 calls to virDomainGetInfo() took ~2.5 seconds. After that
change, 2000 calls to virDomainGetInfo() take 2 *minutes* 45 secs.
We made the change to be able to recover from libvirtd restart in the
middle of a job. However, only destroy and async jobs are taken care of.
Thus it makes more sense to only save domain state XML when these jobs
are started/stopped.
Offline internal snapshots can be rolled back with just a little
bit of refactoring, meaning that we are now automatically atomic.
* src/qemu/qemu_domain.c (qemuDomainSnapshotForEachQcow2): Move
guts...
(qemuDomainSnapshotForEachQcow2Raw): ...to new helper, to allow
rollbacks.
Destination daemon should not rely on the client or source daemon
(depending on the type of migration) to call Finish when migration
fails, because the client may crash before it can do so. The domain
prepared for incoming migration is set to be destroyed (and migration
job cleaned up) when connection with the client closes but this is not
enough. If the associated qemu process crashes after Prepare step and
the domain is cleaned up before the connection gets closed, autodestroy
is not called for the domain and migration jobs remains set. In case the
domain is defined on destination host (i.e., it is not completely
removed once destroyed) we keep the job set for ever. To fix this, we
register a cleanup callback which is responsible to clean migration-in
job when a domain dies anywhere between Prepare and Finish steps. Note
that we can't blindly clean any job when spotting EOF on monitor since
normally an API is running at that time.
With current code, we pass true iff domain is cold booting. However,
if disk is inaccessible and startupPolicy for that disk is set to
'requisite' we have to fail iff cold booting.
When host-model and host-passthrouh CPU modes were introduced, qemu
driver was properly modify to update guest CPU definition during
migration so that we use the right CPU at the destination. However,
similar treatment is needed for (managed)save and snapshots since they
need to save the exact CPU so that a domain can be properly restored.
To avoid repetition of such situation, all places that need live XML
share the code which generates it.
As a side effect, this patch fixes error reporting from
qemuDomainSnapshotWriteMetadata().
This patch fixes console corruption, that happens if two concurrent
sessions are opened for a single console on a domain. Result of this
corruption was that each of the console streams recieved just a part
of the data written to the pipe so every console rendered unusable.
New helper function for safe console handling is used to establish the
console stream connection. This function ensures that no other libvirt
client is using the console (with the ability to disconnect consoles of
libvirt clients) and that no UUCP style lockfile is placed on the PTY
device.
* src/qemu/qemu_domain.h
- add data structure to domain's private data dealing with
console connections
* src/qemu/qemu_domain.c:
- allocate/free domain's console data structure
* src/qemu/qemu_driver.c
- use the new helper function for console handling
Fix my typo at
commit 74e034964c
"disk->rawio == -1" indicates that this value is not
specified. So in case of this, domain must not
be tainted.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
This patch revises qemuProcessStart() function for qemu
processes to retain CAP_SYS_RAWIO if needed.
And in case of that, add taint flag to domain.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Shota Hirae <m11g1401@hibikino.ne.jp>
There is now a standard QEMU guest agent that can be installed
and given a virtio serial channel
<channel type='unix'>
<source mode='bind' path='/var/lib/libvirt/qemu/f16x86_64.agent'/>
<target type='virtio' name='org.qemu.guest_agent.0'/>
</channel>
The protocol that runs over the guest agent is JSON based and
very similar to the JSON monitor. We can't use exactly the same
code because there are some odd differences in the way messages
and errors are structured. The qemu_agent.c file is based on
a combination and simplification of qemu_monitor.c and
qemu_monitor_json.c
* src/qemu/qemu_agent.c, src/qemu/qemu_agent.h: Support for
talking to the agent for shutdown
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Add thread
helpers for talking to the agent
* src/qemu/qemu_process.c: Connect to agent whenever starting
a guest
* src/qemu/qemu_monitor_json.c: Make variable static
There are several reasons for doing this:
- the CPU specification is out of libvirt's control so we cannot
guarantee stable guest ABI
- not every feature of a CPU may actually work as expected when
advertised directly to a guest
- migration between two machines with exactly the same CPU may work but
no guarantees can be made
- this mode is not supported and its use is at one's own risk
VIR_DOMAIN_XML_UPDATE_CPU flag for virDomainGetXMLDesc may be used to
get updated custom mode guest CPU definition in case it depends on host
CPU. This patch implements the same behavior for host-model and
host-passthrough CPU modes.
This fixes https://bugzilla.redhat.com/show_bug.cgi?id=638633
Although scripts are not used by interfaces of type other than
"ethernet" in qemu, due to the fact that the parser stores the script
name in a union that is only valid when type is ethernet or bridge,
there is no way for anyone except the parser itself to catch the
problem of specifying an interface script for an inappropriate
interface type (by the time the parsed data gets back to the code that
called the parser, all evidence that a script was specified is
forgotten).
Since the parser itself should be agnostic to which type of interface
allows scripts (an example of why: a script specified for an interface
of type bridge is valid for xen domains, but not for qemu domains),
the solution here is to move the script out of the union(s) in the
DomainNetDef, always populate it when specified (regardless of
interface type), and let the driver decide whether or not it is
appropriate.
Currently the qemu, xen, libxml, and uml drivers recognize the script
parameter and do something with it (the uml driver only to report that
it isn't supported). Those drivers have been updated to log a
CONFIG_UNSUPPORTED error when a script is specified for an interface
type that's inappropriate for that particular hypervisor.
(NB: There was earlier discussion of solving this problem by adding a
VALIDATE flag to all libvirt APIs that accept XML, which would cause
the XML to be validated against the RNG files. One statement during
that discussion was that the RNG shouldn't contain hypervisor-specific
things, though, and a proper solution to this problem would require
that (again, because a script for an interface of type "bridge" is
accepted by xen, but not by qemu).
Currently all drivers using domain events need to provide a callback
for handling a timer to dispatch events in a clean stack. There is
no technical reason for dispatch to go via driver specific code. It
could trivially be dispatched directly from the domain event code,
thus removing tedious boilerplate code from all drivers
Also fix the libxl & xen drivers to pass 'true' when creating the
virDomainEventState, since they run inside the daemon & thus always
expect events to be present.
* src/conf/domain_event.c, src/conf/domain_event.h: Internalize
dispatch of events from timer callback
* src/libxl/libxl_driver.c, src/lxc/lxc_driver.c,
src/qemu/qemu_domain.c, src/qemu/qemu_driver.c,
src/remote/remote_driver.c, src/test/test_driver.c,
src/uml/uml_driver.c, src/vbox/vbox_tmpl.c,
src/xen/xen_driver.c: Remove all timer dispatch functions
The virTimestamp and virTimeMs functions in src/util/util.h
duplicate functionality from virtime.h, in a non-async signal
safe manner. Remove them, and convert all code over to the new
APIs.
* src/util/util.c, src/util/util.h: Delete virTimeMs and virTimestamp
* src/lxc/lxc_driver.c, src/qemu/qemu_domain.c,
src/qemu/qemu_driver.c, src/qemu/qemu_migration.c,
src/qemu/qemu_process.c, src/util/event_poll.c: Convert to use
virtime APIs
If something fails while initializing qemu job object in
qemuDomainObjPrivateAlloc(), memory to the private pointer is freed, but
after that, the pointer is still dereferenced, which may result in a
segfault.
* qemuDomainObjPrivateAlloc() - Don't dereference NULL pointer.
All constants related to events should have a prefix of
VIR_DOMAIN_EVENT_
* include/libvirt/libvirt.h.in, src/qemu/qemu_domain.c:
Rename VIR_DOMAIN_DISK_CHANGE_MISSING_ON_START to
VIR_DOMAIN_EVENT_DISK_CHANGE_MISSING_ON_START
If a disk source gets dropped because it is not accessible,
mgmt application might want to be informed about this. Therefore
we need to emit an event. The event presented in this patch
is however a bit superset of what written above. The reason is simple:
an intention to be easily expanded, e.g. on 'user ejected disk
in guest' events. Therefore, callback gets source string and disk alias
(which should be unique among a domain) and reason (an integer);
This patch implements on_missing feature in qemu driver.
Upon qemu startup process an accessibility of CDROMs
and floppy disks is checked. The source might get dropped
if unavailable and on_missing is set accordingly.
No event is emit thought. Look for follow up patch.
The XML parser for the qemu specific extensions expects the qemu name-space
to be bound to the 'qemu' prefix. This is too strict, since the name of the
name-space-prefix is only meant as an internal lookup key. Only the associated
URI is relevant.
<domain>...
<qemu:commandline xmlns:qemu="http://libvirt.org/schemas/domain/qemu/1.0">
...</qemu:commandline>
</domain>
<domain xmlns:ns0="http://libvirt.org/schemas/domain/qemu/1.0">...
<ns0:commandline>
...</ns0:commandline>
</domain>
<domain xmlns:qemu="http://libvirt.org/schemas/domain/qemu/1.0">
<qemu:commandline xmlns:qemu="urn:foo">
...</qemu:commandline>
</domain>
Remove the test for checking the name-space binding on the top-level <domain>
element. Registering the name-space with XPath is enough.
Signed-off-by: Philipp Hahn <hahn@univention.de>
Once we know which set of disks belong to a snapshot, reverting or
deleting that snapshot should visit just those disks, rather than
also visiting disks that were hot-plugged in the meantime or
skipping disks that were hot-unplugged in the meantime.
* src/qemu/qemu_domain.c (qemuDomainSnapshotForEachQcow2): Use
snapshot domain details when available. Avoid NULL deref.
Destination libvirtd remembers the original name in the prepare phase
and clears it in the finish phase. The original name is used when
comparing domain name in migration cookie.
Currently, qemuDomainGetXMLDesc and qemudDomainGetInfo check for
outstanding synchronous job before (eventual) monitor entering.
However, there can be already async job set, e.g. migration.
The previous patch removed all snapshots, but not the directory
where the snapshots lived, which is still a form of stale data.
* src/qemu/qemu_domain.c (qemuDomainRemoveInactive): Wipe any
snapshot directory.
This patch is mostly code motion - moving some functions out
of qemu_driver and into qemu_domain so they can be reused by
multiple qemu_* files (since qemu_driver.h must not grow).
It also adds a new helper function, qemuDomainRemoveInactive,
which will be used in the next patch.
* src/qemu/qemu_domain.h (qemuFindQemuImgBinary)
(qemuDomainSnapshotWriteMetadata, qemuDomainSnapshotForEachQcow2)
(qemuDomainSnapshotDiscard, qemuDomainSnapshotDiscardAll)
(qemuDomainRemoveInactive): New prototypes.
(struct qemu_snap_remove): New struct.
* src/qemu/qemu_domain.c (qemuDomainRemoveInactive)
(qemuDomainSnapshotDiscardAllMetadata): New functions.
(qemuFindQemuImgBinary, qemuDomainSnapshotWriteMetadata)
(qemuDomainSnapshotForEachQcow2, qemuDomainSnapshotDiscard)
(qemuDomainSnapshotDiscardAll): Move here...
* src/qemu/qemu_driver.c (qemuFindQemuImgBinary)
(qemuDomainSnapshotWriteMetadata, qemuDomainSnapshotForEachQcow2)
(qemuDomainSnapshotDiscard, qemuDomainSnapshotDiscardAll): ...from
here.
(qemuDomainUndefineFlags): Update caller.
* src/conf/domain_conf.c (virDomainRemoveInactive): Doc fixes.
The maximum bandwidth that can be consumed when migrating a domain
is better classified as an operational vs configuration parameter of
the dommain. As such, store this parameter in qemuDomainObjPrivate
structure.
This patch creates an optional BeginJob queue size limit. When
active, all other attempts above level will fail. To set this
feature assign desired value to max_queued variable in qemu.conf.
Setting it to 0 turns it off.
Currently, we attempt to run sync job and async job at the same time. It
means that the monitor commands for two jobs can be run in any order.
In the function qemuDomainObjEnterMonitorInternal():
if (priv->job.active == QEMU_JOB_NONE && priv->job.asyncJob) {
if (qemuDomainObjBeginNestedJob(driver, obj) < 0)
We check whether the caller is an async job by priv->job.active and
priv->job.asynJob. But when an async job is running, and a sync job is
also running at the time of the check, then priv->job.active is not
QEMU_JOB_NONE. So we cannot check whether the caller is an async job
in the function qemuDomainObjEnterMonitorInternal(), and must instead
put the burden on the caller to tell us when an async command wants
to do a nested job.
Once the burden is on the caller, then only async monitor enters need
to worry about whether the VM is still running; for sync monitor enter,
the internal return is always 0, so lots of ignore_value can be dropped.
* src/qemu/THREADS.txt: Reflect new rules.
* src/qemu/qemu_domain.h (qemuDomainObjEnterMonitorAsync): New
prototype.
* src/qemu/qemu_process.h (qemuProcessStartCPUs)
(qemuProcessStopCPUs): Add parameter.
* src/qemu/qemu_migration.h (qemuMigrationToFile): Likewise.
(qemuMigrationWaitForCompletion): Make static.
* src/qemu/qemu_domain.c (qemuDomainObjEnterMonitorInternal): Add
parameter.
(qemuDomainObjEnterMonitorAsync): New function.
(qemuDomainObjEnterMonitor, qemuDomainObjEnterMonitorWithDriver):
Update callers.
* src/qemu/qemu_driver.c (qemuDomainSaveInternal)
(qemudDomainCoreDump, doCoreDump, processWatchdogEvent)
(qemudDomainSuspend, qemudDomainResume, qemuDomainSaveImageStartVM)
(qemuDomainSnapshotCreateActive, qemuDomainRevertToSnapshot):
Likewise.
* src/qemu/qemu_process.c (qemuProcessStopCPUs)
(qemuProcessFakeReboot, qemuProcessRecoverMigration)
(qemuProcessRecoverJob, qemuProcessStart): Likewise.
* src/qemu/qemu_migration.c (qemuMigrationToFile)
(qemuMigrationWaitForCompletion, qemuMigrationUpdateJobStatus)
(qemuMigrationJobStart, qemuDomainMigrateGraphicsRelocate)
(doNativeMigrate, doTunnelMigrate, qemuMigrationPerformJob)
(qemuMigrationPerformPhase, qemuMigrationFinish)
(qemuMigrationConfirm): Likewise.
* src/qemu/qemu_hotplug.c: Drop unneeded ignore_value.
qemuMigrationUpdateJobStatus (called in a loop by migration
and save tasks) uses qemuDomainObjEnterMonitorWithDriver;
however, that function ended up starting a nested job without
releasing the driver.
Since no one else is making nested calls, we can inline the
internal functions to properly track driver_locked.
* src/qemu/qemu_domain.h (qemuDomainObjBeginNestedJob)
(qemuDomainObjBeginNestedJobWithDriver)
(qemuDomainObjEndNestedJob): Drop unused prototypes.
* src/qemu/qemu_domain.c (qemuDomainObjEnterMonitorInternal):
Reflect driver lock to nested job.
(qemuDomainObjBeginNestedJob)
(qemuDomainObjBeginNestedJobWithDriver)
(qemuDomainObjEndNestedJob): Drop unused functions.
Asynchronous jobs may take long time to finish and may consist of
several phases which we need to now about to help with recovery/rollback
after libvirtd restarts.
Query commands are safe to be called during long running jobs (such as
migration). This patch makes them all work without the need to
special-case every single one of them.
The patch introduces new job.asyncCond condition and associated
job.asyncJob which are dedicated to asynchronous (from qemu monitor
point of view) jobs that can take arbitrarily long time to finish while
qemu monitor is still usable for other commands.
The existing job.active (and job.cond condition) is used all other
synchronous jobs (including the commands run during async job).
Locking schema is changed to use these two conditions. While asyncJob is
active, only allowed set of synchronous jobs is allowed (the set can be
different according to a particular asyncJob) so any method that
communicates to qemu monitor needs to check if it is allowed to be
executed during current asyncJob (if any). Once the check passes, the
method needs to normally acquire job.cond to ensure no other command is
running. Since domain object lock is released during that time, asyncJob
could have been started in the meantime so the method needs to recheck
the first condition. Then, normal jobs set job.active and asynchronous
jobs set job.asyncJob and optionally change the list of allowed job
groups.
Since asynchronous jobs only set job.asyncJob, other allowed commands
can still be run when domain object is unlocked (when communicating to
remote libvirtd or sleeping). To protect its own internal synchronous
commands, the asynchronous job needs to start a special nested job
before entering qemu monitor. The nested job doesn't check asyncJob, it
only acquires job.cond and sets job.active to block other jobs.
EnterMonitor and ExitMonitor methods are very similar to their
*WithDriver variants; consolidate them into EnterMonitorInternal and
ExitMonitorInternal to avoid (mainly future) code duplication.
Coverity warns if the majority of callers check a function for
errors, but a few don't; but in qemu_audit and qemu_domain, the
choice to not check for failures was safe. In qemu_command, the
failure to generate a uuid can only occur on a bad pointer.
* src/qemu/qemu_audit.c (qemuAuditCgroup): Ignore failure to get
cgroup controller.
* src/qemu/qemu_domain.c (qemuDomainObjEnterMonitor)
(qemuDomainObjEnterMonitorWithDriver): Ignore failure to get
timestamp.
* src/qemu/qemu_command.c (qemuParseCommandLine): Check for error.
The code emitting taint warnings was mistakenly thinking
that guests run from the QEMU session driver were tainted
for having high privileges. This is of course nonsense
since the session driver is always unprivileged
* src/qemu/qemu_domain.c: Don't warn for high privileges in
non-privileged QEMU
Since we virEventRegisterDefaultImpl is now a public API, callers need
a way to invoke the default registered Handle and Timeout functions. We
already have general functions for these internally, so promote
them to the public API.
v2:
Actually add APIs to libvirt.h
The QEMU integrates with the lock manager instructure in a number
of key places
* During startup, a lock is acquired in between the fork & exec
* During startup, the libvirtd process acquires a lock before
setting file labelling
* During shutdown, the libvirtd process acquires a lock
before restoring file labelling
* During hotplug, unplug & media change the libvirtd process
holds a lock while setting/restoring labels
The main content lock is only ever held by the QEMU child process,
or libvirtd during VM shutdown. The rest of the operations only
require libvirtd to hold the metadata locks, relying on the active
QEMU still holding the content lock.
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h,
src/qemu/libvirtd_qemu.aug, src/qemu/test_libvirtd_qemu.aug:
Add config parameter for configuring lock managers
* src/qemu/qemu_driver.c: Add calls to the lock manager
Update the qemuDomainMigrateBegin method so that it accepts
an optional incoming XML document. This will be validated
for ABI compatibility against the current domain config,
and if this check passes, will be passed back out for use
by the qemuDomainMigratePrepare method on the target
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h,
src/qemu/qemu_migration.c: Allow custom XML to be passed
Originally most of libvirt domain-specific calls were blocking
during a migration.
A new mechanism to allow specific calls (blkstat/blkinfo) to be
executed in such condition has been implemented.
In the long term it'd be desirable to get a more general
solution to mark further APIs as migration safe, without needing
special case code.
* src/qemu/qemu_migration.c: add some additional job signal
flags for doing blkstat/blkinfo during a migration
* src/qemu/qemu_domain.c: add a condition variable that can be
used to efficiently wait for the migration code to clear the
signal flag
* src/qemu/qemu_driver.c: execute blkstat/blkinfo using the
job signal flags during migration
These VIR_XXXX0 APIs make us confused, use the non-0-suffix APIs instead.
How do these coversions works? The magic is using the gcc extension of ##.
When __VA_ARGS__ is empty, "##" will swallow the "," in "fmt," to
avoid compile error.
example: origin after CPP
high_level_api("%d", a_int) low_level_api("%d", a_int)
high_level_api("a string") low_level_api("a string")
About 400 conversions.
8 special conversions:
VIR_XXXX0("") -> VIR_XXXX("msg") (avoid empty format) 2 conversions
VIR_XXXX0(string_literal_with_%) -> VIR_XXXX(%->%%) 0 conversions
VIR_XXXX0(non_string_literal) -> VIR_XXXX("%s", non_string_literal)
(for security) 6 conversions
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
As well as taint warnings going to the main libvirt log,
add taint warnings to the per-domain logfile
Domain id=3 is tainted: high-privileges
Domain id=3 is tainted: disk-probing
Domain id=3 is tainted: shell-scripts
Domain id=3 is tainted: custom-monitor
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Enhance
qemuDomainTaint to also log to the domain logfile
* src/qemu/qemu_driver.c: Pass -1 for logFD to taint methods to
auto-append to logfile
* src/qemu/qemu_process.c: Pass open logFD at startup for taint
methods
The qemuDomainAppendLog method allows writing a formatted string
to the end of the domain logfile, optionally opening it if needed.
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Add
qemuDomainAppendLog
Move the qemuProcessLogReadFD and qemuProcessLogFD methods
into qemu_domain.c, renaming them to qemuDomainCreateLog
and qemuDomainOpenLog.
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Add
qemuDomainCreateLog and qemuDomainOpenLog.
* src/qemu/qemu_process.c: Remove qemuProcessLogFD
and qemuProcessLogReadFD
Wire up logging of VM tainting to the QEMU driver
- If running QEMU as root user/group or without capabilities
being cleared
- If passing custom QEMU command line args
- If issuing custom QEMU monitor commands
- If using a network interface config with an associated
shell script
- If using a disk config relying on format probing
The warnings, per-VM appear in the main libvirtd logs
11:56:17.571: 10832: warning : qemuDomainObjTaint:712 : Domain id=1 name='l2' uuid=c7a3edbd-edaf-9455-926a-d65c16db1802 is tainted: high-privileges
11:56:17.571: 10832: warning : qemuDomainObjTaint:712 : Domain id=1 name='l2' uuid=c7a3edbd-edaf-9455-926a-d65c16db1802 is tainted: disk-probing
The taint flags are reset when the VM is stopped.
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Helper APIs
for logging taint warnings
* src/qemu/qemu_driver.c: Log tainting with custom QEMU monitor
commands and disk/net hotplug with unsupported configs
* src/qemu/qemu_process.c: Log tainting at startup based on
unsupported configs
We already have virAsprintf, so picking a similar name helps for
seeing a similar purpose. Furthermore, the prefix V before printf
generally implies 'va_list', even though this variant was '...', and
the old name got in the way of adding a new va_list version.
global rename performed with:
$ git grep -l virBufferVSprintf \
| xargs -L1 sed -i 's/virBufferVSprintf/virBufferAsprintf/g'
then revert the changes in ChangeLog-old.
To cope with the QEMU binary being changed while a VM is running,
it is neccessary to persist the original qemu capabilities at the
time the VM is booted.
* src/qemu/qemu_capabilities.c, src/qemu/qemu_capabilities.h: Add
an enum for a string rep of every capability
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Support for
storing capabilities in the domain status XML
* src/qemu/qemu_process.c: Populate & free QEMU capabilities at
domain startup
In qemuDomainObjBeginJobWithDriver, when virCondWaitUntil timeouts,
the function tries to call qemuDriverLock with virDomainObj locked,
this causes the dead-lock problem. This patch fixes this.
Add the compiler attribute to ensure we don't introduce any more
ref bugs like were just patched in commit 9741f34, then explicitly
mark the remaining places in code that are safe.
* src/qemu/qemu_monitor.h (qemuMonitorUnref): Mark
ATTRIBUTE_RETURN_CHECK.
* src/conf/domain_conf.h (virDomainObjUnref): Likewise.
* src/conf/domain_conf.c (virDomainObjParseXML)
(virDomainLoadStatus): Fix offenders.
* src/openvz/openvz_conf.c (openvzLoadDomains): Likewise.
* src/vmware/vmware_conf.c (vmwareLoadDomains): Likewise.
* src/qemu/qemu_domain.c (qemuDomainObjBeginJob)
(qemuDomainObjBeginJobWithDriver)
(qemuDomainObjExitRemoteWithDriver): Likewise.
* src/qemu/qemu_monitor.c (QEMU_MONITOR_CALLBACK): Likewise.
Suggested by Daniel P. Berrange.
Steps to reproduce this bug:
# cat test.sh
#! /bin/bash -x
virsh start domain
sleep 5
virsh qemu-monitor-command domain 'cpu_set 2 online' --hmp
# while true; do ./test.sh ; done
Then libvirtd will crash.
The reason is that:
we add a reference of obj when we open the monitor. We will reduce this
reference when we free the monitor.
If the reference of monitor is 0, we will free monitor automatically and
the reference of obj is reduced.
But in the function qemuDomainObjExitMonitorWithDriver(), we reduce this
reference again when the reference of monitor is 0.
It will cause the obj be freed in the function qemuDomainObjEndJob().
Then we start the domain again, and libvirtd will crash in the function
virDomainObjListSearchName(), because we pass a null pointer(obj->def->name)
to strcmp().
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
The introduction of the v3 migration protocol, along with
support for migration cookies, will significantly expand
the size of the migration code. Move it all to a separate
file to make it more manageable
The functions are not moved 100%. The API entry points
remain in the main QEMU driver, but once the public
virDomainPtr is resolved to the internal virDomainObjPtr,
all following code is moved.
This will allow the new v3 API entry points to call into the
same shared internal migration functions
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Add
qemuDomainFormatXML helper method
* src/qemu/qemu_driver.c: Remove all migration code
* src/qemu/qemu_migration.c, src/qemu/qemu_migration.h: Add
all migration code.
Move the qemudStartVMDaemon and qemudShutdownVMDaemon
methods into a separate file, renaming them to
qemuProcessStart, qemuProcessStop. All helper methods
called by these are also moved & renamed to match
* src/Makefile.am: Add qemu_process.c/.h
* src/qemu/qemu_command.c: Add qemuDomainAssignPCIAddresses
* src/qemu/qemu_command.h: Add VNC port min/max
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Add
domain event queue helpers
* src/qemu/qemu_driver.c, src/qemu/qemu_driver.h: Remove
all QEMU process startup/shutdown functions
* src/qemu/qemu_process.c, src/qemu/qemu_process.h: Add
all QEMU process startup/shutdown functions
To allow the APIs to be used from separate files, move the domain
lock / job helper code into qemu_domain.c
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Add domain lock
/ job code
* src/qemu/qemu_driver.c: Remove domain lock / job code
Move the code for handling the QEMU virDomainObjPtr private
data, and custom XML namespace into a separate file
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: New file
for private data & namespace code
* src/qemu/qemu_driver.c, src/qemu/qemu_driver.h: Remove
private data & namespace code
* src/qemu/qemu_driver.h, src/qemu/qemu_command.h: Update
includes
* src/Makefile.am: Add src/qemu/qemu_domain.c
