Commit Graph

55 Commits

Author SHA1 Message Date
Peter Krempa
1dcc4c7ffd qemu: iothread: Aggregate code to set IOThread tuning
Rather than iterating 3 times for various settings this function
aggregates all the code into single place. One of the other advantages
is that it can then be reused for properly setting IOThread info on
hotplug.
2016-02-08 17:05:00 +01:00
Peter Krempa
56971667ee qemu: vcpu: Aggregate code to set vCPU tuning
Rather than iterating 3 times for various settings this function
aggregates all the code into single place. One of the other advantages
is that it can then be reused for properly setting vCPU info on hotplug.

With this approach autoCpuset is also used when setting the process
affinity rather than just via cgroups.
2016-02-08 17:05:00 +01:00
Peter Krempa
c07bc2cc7d qemu: process: Extract pre-start checks into a function
When starting a qemu process there are certain checks done to ensure
that the configuration makes sense. Extract them into a separate
function so that they can be reused in the test code.
2016-02-08 09:19:48 +01:00
Cole Robinson
92549b3b8a qemu: Mark some functions as static 2016-02-01 10:33:25 -05:00
Jiri Denemark
f87668b70e qemu: Fix NBD migration with default listenAddress
My commit 674afcb09e moved computing the
default listen address from qemuMigrationPrepareAny to
qemuMigrationPrepareIncoming. However, I didn't notice listenAddress was
later passed to qemuMigrationStartNBDServer. Thus, it would be called
with the original value of listenAddress (NULL).

Let's add the updated listen address to qemuProcessIncomingDef and use
it when starting NBD servers.

Reported-by: Michael Chapman <mike@very.puzzling.org>
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2016-01-08 10:39:20 +01:00
Daniel P. Berrange
a48539c013 qemu: convert monitor to use qemuDomainLogContextPtr indirectly
Currently the QEMU monitor is given an FD to the logfile. This
won't work in the future with virtlogd, so it needs to use the
qemuDomainLogContextPtr instead, but it shouldn't directly
access that object either. So define a callback that the
monitor can use for reporting errors from the log file.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-11-26 14:30:15 +00:00
Daniel P. Berrange
69b0992178 qemu: unify code for reporting errors from QEMU log files
There are two pretty similar functions qemuProcessReadLog and
qemuProcessReadChildErrors. Both read from the QEMU log file
and try to strip out libvirt messages. The latter then reports
an error, while the former lets the callers report an error.

Re-write qemuProcessReadLog so that it uses a single read
into a dynamically allocated buffer. Then introduce a new
qemuProcessReportLogError that calls qemuProcessReadLog
and reports an error.

Convert all callers to use qemuProcessReportLogError.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-11-26 14:30:15 +00:00
Jiri Denemark
0004ddf0f6 qemu: Introduce qemuProcessFinishStartup
Finishes starting a new domain launched by qemuProcessLaunch.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2015-11-25 15:27:31 +01:00
Jiri Denemark
f618d662ca qemu: Introduce qemuProcessLaunch
Once qemuProcessInit was called, qemuProcessLaunch will launch a new
QEMU process with stopped virtual CPUs.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2015-11-25 15:27:31 +01:00
Jiri Denemark
b5ffd224f1 qemu: Introduce qemuProcessInit
qemuProcessStart is going to be split in three parts: qemuProcessInit,
qemuProcessLaunch, and qemuProcessFinish so that migration Prepare phase
can insert additional code in the process. qemuProcessStart will be a
small wrapper for all other callers.

qemuProcessInit prepares the domain up to the point when priv->qemuCaps
is initialized.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2015-11-25 15:27:31 +01:00
Jiri Denemark
2c4ba8b4f3 qemu: Use -incoming defer for migrations
Traditionally, we pass incoming migration URI on QEMU command line,
which has some drawbacks. Depending on the URI QEMU may initialize its
migration state immediately without giving us a chance to set any
additional migration parameters (this applies mainly for fd: URIs). For
some URIs the monitor may be completely blocked from the beginning until
migration is finished, which means we may be stuck in qmp_capabilities
command without being able to send any QMP commands.

QEMU solved this by introducing "defer" parameter for -incoming command
line option. This will tell QEMU to prepare for an incoming migration
while the actual incoming URI is sent using migrate-incoming QMP
command. Before calling this command we can normally talk to the
monitor and even set any migration parameters which will be honored by
the incoming migration.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2015-11-19 09:41:23 +01:00
Jiri Denemark
04c721f22d qemu: Always set async job when starting a domain
We only started an async job for incoming migration from another host.
When we were starting a domain from scratch or restoring from a saved
state (migration from file) we didn't set any async job. Let's introduce
a new QEMU_ASYNC_JOB_START for these cases.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2015-11-19 09:41:23 +01:00
Jiri Denemark
2bf5333f45 qemu: Introduce qemuProcessIncomingDef
Incoming migration may require quite a few parameters (URI, fd, path) to
be considered while starting QEMU and we will soon add another one.
Let's group all of them in a single struct.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2015-11-19 09:41:23 +01:00
Peter Krempa
a03e2d3a99 qemu: Connect to guest agent after channel hotplug
If a user hot-attaches the guest agent channel libvirt would ignore it
until the restart of libvirtd or shutdown/destroy and start of the VM
itself.

This patch adds code that opens or closes the guest agent connection
according to the state of the guest agent channel according to
connect/disconnect events.

To allow opening the channel from the event handler qemuConnectAgent
needed to be exported.
2015-04-26 17:19:22 +02:00
Peter Krempa
98f08aba8e qemu: cgroup: Use priv->autoCpuset instead of using qemuPrepareCpumap()
Two places would call to qemuPrepareCpumap() with priv->autoNodeset to
convert it to a cpuset. Remove the function and use the prepared cpuset
automatically.
2015-04-02 10:12:08 +02:00
Peter Krempa
5c634730b9 qemu: process: Export qemuProcessFindDomainDiskByAlias 2015-03-16 10:57:33 +01:00
Pavel Hrdina
e4983952b4 qemu: remove duplicated code for allocating spice ports
We have two different places that needs to be updated while touching
code for allocation spice ports.  Add a bool option to
'qemuProcessSPICEAllocatePorts' function to switch between true and fake
allocation so we can use this function also in qemu_driver to generate
native domain definition.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2015-03-03 11:41:46 +01:00
Martin Kletzander
104ba5966a qemu: Add support for setting vCPU and I/O thread scheduler setting
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1178986

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2015-02-11 17:30:07 +01:00
Sam Bobroff
f0f9eed843 qemu: Tidy up job handling during live migration
During a QEMU live migration several warning messages about job
handling could be written to syslog on the destination host:

"entering monitor without asking for a nested job is dangerous"

The messages are written because the job handling during migration
uses hard coded asyncJob values in several places that are incorrect.

This patch passes the required asyncJob value around and prevents
the warnings as well as any issues that the warnings may be referring
to.

https://bugzilla.redhat.com/show_bug.cgi?id=1130089

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2014-08-14 12:12:42 +02:00
Julio Faracco
aa990efe97 qemu: enum cleanups in "src/qemu/*"
As we are doing with the enum structures, a cleanup in "src/qemu/"
directory was done now. All the enums that were defined in the
header files were converted to typedefs in this directory. This
patch includes all the adjustments to remove conflicts when you do
this kind of change. "Enum-to-typedef"'s conversions were made in
"src/qemu/qemu_{capabilities, domain, migration, hotplug}.h".

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
2014-06-24 12:56:54 -06:00
Julio Faracco
1b14c449b8 util: use typedefs for enums in "src/util/" directory
In "src/util/" there are many enumeration (enum) declarations.
Sometimes, it's better using a typedef for variable types,
function types and other usages. Other enumeration will be
changed to typedef's in the future.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2014-05-05 14:30:01 -06:00
Peter Krempa
310651a5e3 qemu_process: Make qemuProcessReadLog() more versatile and reusable
Teach the function to skip character device definitions printed by qemu
at startup in addition to libvirt log messages and make it usable from
outside of qemu_process.c. Also add documentation about the func.
2013-09-25 13:50:56 +02:00
Jiri Denemark
b2f76cd20e qemu: Export qemuProcessHandleDeviceDeleted for tests 2013-08-26 16:09:55 +02:00
Chen Fan
e8ccf7ed8a qemu: expose qemuProcessShutdownOrReboot()
Later code will need this outside of qemu_process.c
2013-07-02 12:02:27 -06:00
Osier Yang
99fdd434bc qemu: Move qemuSetUnprivSGIO into qemu_conf.c
unpriv_sgio setting is tight with the shared device helpers, let's
put them together in qemu_conf.c
2013-05-17 00:51:58 +08:00
Daniel P. Berrange
d0b3ee55ec Fix typo in internal VIR_QEMU_PROCESS_START_AUTODESROY constant
s/VIR_QEMU_PROCESS_START_AUTODESROY/VIR_QEMU_PROCESS_START_AUTODESTROY/

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-02-27 22:51:24 +00:00
Osier Yang
371df778eb qemu: Merge qemuCheckSharedDisk into qemuAddSharedDisk
Based on moving various checking into qemuAddSharedDisk, this
avoids the caller using it in wrong ways. Also this adds two
new checking for qemuCheckSharedDisk (disk device not 'lun'
and kernel doesn't support unpriv_sgio simply returns 0).
2013-02-21 00:31:24 +08:00
Daniel P. Berrange
a9e97e0c30 Remove qemuDriverLock from almost everywhere
With the majority of fields in the virQEMUDriverPtr struct
now immutable or self-locking, there is no need for practically
any methods to be using the QEMU driver lock. Only a handful
of helper APIs in qemu_conf.c now need it
2013-02-13 11:10:30 +00:00
Daniel P. Berrange
8cdd5faf46 Pass virQEMUDriverPtr into APIs managed shared disk list
Currently the APIs for managing the shared disk list take
a virHashTablePtr as the primary argument. This is bad
because it requires the caller to deal with locking of
the QEMU driver. Switch the APIs to take the full
virQEMUDriverPtr instance

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-02-11 12:48:22 +00:00
Daniel P. Berrange
b090aa7d55 Introduce a virQEMUDriverConfigPtr object
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>
2013-02-05 15:49:25 +00:00
Osier Yang
1279e421b2 qemu: Check if the shared disk's cdbfilter conflicts with others
This prevents domain starting and disk attaching if the shared disk's
setting conflicts with other active domain(s), E.g. A domain with
"sgio" set as "filtered", however, another active domain is using
it set as "unfiltered".
2013-01-07 21:39:20 +08:00
Osier Yang
278f87c4b5 qemu: set unpriv_sgio when starting domain and attaching disk
This ignores the default "filtered" if unpriv_sgio is not supported
by kernel, but for explicit request "filtered", it error out for
domain starting.
2013-01-07 21:39:06 +08:00
Daniel P. Berrange
4738c2a7e7 Replace 'struct qemud_driver *' with virQEMUDriverPtr
Remove the obsolete 'qemud' naming prefix and underscore
based type name. Introduce virQEMUDriverPtr as the replacement,
in common with LXC driver naming style
2012-11-28 18:17:25 +00:00
Osier Yang
0039a32fca qemu: Add helper to prepare cpumap for affinity setting
Abstract the codes to prepare cpumap into a helper a function,
which can be used later.

* src/qemu/qemu_process.h: Declare qemuPrepareCpumap
* src/qemu/qemu_process.c: Implement qemuPrepareCpumap, and use it.
2012-10-24 21:24:10 +08:00
Eric Blake
4ecb723b9e maint: fix up copyright notice inconsistencies
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/
2012-09-20 16:30:55 -06:00
Daniel P. Berrange
5f2f8d4180 Remove unused qemuProcessAutoDestroyRun decl from header
The qemuProcessAutoDestroyRun function was removed in an earlier
commit, but the header file declaration was not deleted
2012-08-15 10:50:49 +01:00
Osier Yang
f9ce7dad60 Desert the FSF address in copyright
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
2012-07-23 10:50:50 +08:00
Michal Privoznik
86032b2276 qemu: Don't overwrite security labels
Currently, if qemuProcessStart fail at some point, e.g. because
domain being started wants a PCI/USB device already assigned to
a different domain, we jump to cleanup label where qemuProcessStop
is performed. This unconditionally calls virSecurityManagerRestoreAllLabel
which is wrong because the other domain is still using those devices.

However, once we successfully label all devices/paths in
qemuProcessStart() from that point on, we have to perform a rollback
on failure - that is - we have to virSecurityManagerRestoreAllLabel.
2012-06-12 11:14:38 +02:00
Michal Privoznik
69dd77149c qemuProcessStop: Switch to flags
Currently, we are passing only one boolean (migrated) so there is
no real profit in this. But it creates starting position for
next patch.
2012-06-12 09:57:02 +02:00
Michal Privoznik
63ddc65d63 qemuProcessStart: Switch to flags instead of bunch booleans
Currently, we have 3 boolean arguments we have to pass
to qemuProcessStart(). As libvirt grows it is harder and harder
to remember them and their position. Therefore we should
switch to flags instead.
2012-04-16 17:20:04 +02:00
Wen Congyang
ff68d6eeb5 fix a deadlock when qemu cannot start
When qemu cannot start, we may call qemuProcessStop() twice.
We have check whether the vm is running at the beginning of
qemuProcessStop() to avoid libvirt deadlock. We call
qemuProcessStop() with driver and vm locked. It seems that
we can avoid libvirt deadlock. But unfortunately we may
unlock driver and vm in the function qemuProcessKill() while
vm->def->id is not -1. So qemuProcessStop() will be run twice,
and monitor will be freed unexpectedly. So we should set
vm->def->id to -1 at the beginning of qemuProcessStop().
2012-03-30 14:21:49 +08:00
Michal Privoznik
b819b3b7cf qemu: Fix startupPolicy for snapshot-revert
Currently, startupPolicy='requisite' was determining cold boot
by migrateFrom != NULL. That means, if domain was started up
with migrateFrom set we didn't require disk source path and allowed
it to be dropped. However, on snapshot-revert domain wasn't migrated
but according to documentation, requisite should drop disk source
as well.
2012-03-08 10:03:08 +01:00
Eric Blake
3e2c3d8f6d build: use correct type for pid and similar types
No thanks to 64-bit windows, with 64-bit pid_t, we have to avoid
constructs like 'int pid'.  Our API in libvirt-qemu cannot be
changed without breaking ABI; but then again, libvirt-qemu can
only be used on systems that support UNIX sockets, which rules
out Windows (even if qemu could be compiled there) - so for all
points on the call chain that interact with this API decision,
we require a different variable name to make it clear that we
audited the use for safety.

Adding a syntax-check rule only solves half the battle; anywhere
that uses printf on a pid_t still needs to be converted, but that
will be a separate patch.

* cfg.mk (sc_correct_id_types): New syntax check.
* src/libvirt-qemu.c (virDomainQemuAttach): Document why we didn't
use pid_t for pid, and validate for overflow.
* include/libvirt/libvirt-qemu.h (virDomainQemuAttach): Tweak name
for syntax check.
* src/vmware/vmware_conf.c (vmwareExtractPid): Likewise.
* src/driver.h (virDrvDomainQemuAttach): Likewise.
* tools/virsh.c (cmdQemuAttach): Likewise.
* src/remote/qemu_protocol.x (qemu_domain_attach_args): Likewise.
* src/qemu_protocol-structs (qemu_domain_attach_args): Likewise.
* src/util/cgroup.c (virCgroupPidCode, virCgroupKillInternal):
Likewise.
* src/qemu/qemu_command.c(qemuParseProcFileStrings): Likewise.
(qemuParseCommandLinePid): Use pid_t for pid.
* daemon/libvirtd.c (daemonForkIntoBackground): Likewise.
* src/conf/domain_conf.h (_virDomainObj): Likewise.
* src/probes.d (rpc_socket_new): Likewise.
* src/qemu/qemu_command.h (qemuParseCommandLinePid): Likewise.
* src/qemu/qemu_driver.c (qemudGetProcessInfo, qemuDomainAttach):
Likewise.
* src/qemu/qemu_process.c (qemuProcessAttach): Likewise.
* src/qemu/qemu_process.h (qemuProcessAttach): Likewise.
* src/uml/uml_driver.c (umlGetProcessInfo): Likewise.
* src/util/virnetdev.h (virNetDevSetNamespace): Likewise.
* src/util/virnetdev.c (virNetDevSetNamespace): Likewise.
* tests/testutils.c (virtTestCaptureProgramOutput): Likewise.
* src/conf/storage_conf.h (_virStoragePerms): Use mode_t, uid_t,
and gid_t rather than int.
* src/security/security_dac.c (virSecurityDACSetOwnership): Likewise.
* src/conf/storage_conf.c (virStorageDefParsePerms): Avoid
compiler warning.
2012-03-02 06:57:43 -07:00
Laine Stump
595e26c086 qemu: drop driver lock while trying to terminate qemu process
This patch is based on an earlier patch by Eric Blake which was never
committed:

https://www.redhat.com/archives/libvir-list/2011-November/msg00243.html

Aside from rebasing, this patch only drops the driver lock once (prior
to the first time the function sleeps), then leaves it dropped until
it returns (Eric's patch would drop and re-acquire the lock around
each call to sleep).

At the time Eric sent his patch, the response (from Dan Berrange) was
that, while it wasn't a good thing to be holding the driver lock while
sleeping, we really need to rethink locking wrt the driver object,
switching to a finer-grained approach that locks individual items
within the driver object separately to allow for greater concurrency.

This is a good plan, and at the time it made sense to not apply the
patch because there was no known bug related to the driver lock being
held in this function.

However, we now know that the length of the wait in qemuProcessKill is
sometimes too short to allow the qemu process to fully flush its disk
cache before SIGKILL is sent, so we need to lengthen the timeout (in
order to improve the situation with management applications until they
can be updated to use the new VIR_DOMAIN_DESTROY_GRACEFUL flag added
in commit 72f8a7f197). But, if we
lengthen the timeout, we also lengthen the amount of time that all
other threads in libvirtd are essentially blocked from doing anything
(since just about everything needs to acquire the driver lock, if only
for long enough to get a pointer to a domain).

The solution is to modify qemuProcessKill to drop the driver lock
while sleeping, as proposed in Eric's patch. Then we can increase the
timeout with a clear conscience, and thus at least lower the chances
that someone running with existing management software will suffer the
consequence's of qemu's disk cache not being flushed.

In the meantime, we still should work on Dan's proposal to make
locking within the driver object more fine grained.

(NB: although I couldn't find any instance where qemuProcessKill() was
called with no jobs active for the domain (or some other guarantee
that the current thread had at least one refcount on the domain
object), this patch still follows Eric's method of temporarily adding
a ref prior to unlocking the domain object, because I couldn't
convince myself 100% that this was the case.)
2012-02-15 13:57:10 -05:00
Laine Stump
72f8a7f197 qemu: new GRACEFUL flag for virDomainDestroy w/ QEMU support
When libvirt's virDomainDestroy API is shutting down the qemu process,
it first sends SIGTERM, then waits for 1.6 seconds and, if it sees the
process still there, sends a SIGKILL.

There have been reports that this behavior can lead to data loss
because the guest running in qemu doesn't have time to flush its disk
cache buffers before it's unceremoniously whacked.

This patch maintains that default behavior, but provides a new flag
VIR_DOMAIN_DESTROY_GRACEFUL to alter the behavior. If this flag is set
in the call to virDomainDestroyFlags, SIGKILL will never be sent to
the qemu process; instead, if the timeout is reached and the qemu
process still exists, virDomainDestroy will return an error.

Once this patch is in, the recommended method for applications to call
virDomainDestroyFlags will be with VIR_DOMAIN_DESTROY_GRACEFUL
included. If that fails, then the application can decide if and when
to call virDomainDestroyFlags again without
VIR_DOMAIN_DESTROY_GRACEFUL (to force the issue with SIGKILL).

(Note that this does not address the issue of existing applications
that have not yet been modified to use VIR_DOMAIN_DESTROY_GRACEFUL.
That is a separate patch.)
2012-02-03 14:21:17 -05:00
Daniel P. Berrange
43925db7ca Rename Macvtap management APIs
In preparation for code re-organization, rename the Macvtap
management APIs to have the following patterns

  virNetDevMacVLanXXXXX     - macvlan/macvtap interface management
  virNetDevVPortProfileXXXX - virtual port profile management

* src/util/macvtap.c, src/util/macvtap.h: Rename APIs
* src/conf/domain_conf.c, src/network/bridge_driver.c,
  src/qemu/qemu_command.c, src/qemu/qemu_command.h,
  src/qemu/qemu_driver.c, src/qemu/qemu_hotplug.c,
  src/qemu/qemu_migration.c, src/qemu/qemu_process.c,
  src/qemu/qemu_process.h: Update for renamed APIs
2011-11-18 16:10:01 +00:00
Jiri Denemark
96fc478417 qemu: Prevent disk corruption on domain shutdown
Ever since we introduced fake reboot, we call qemuProcessKill as a
reaction to SHUTDOWN event. Unfortunately, qemu doesn't guarantee it
flushed all internal buffers before sending SHUTDOWN, in which case
killing the process forcibly may result in (virtual) disk corruption.

By sending just SIGTERM without SIGKILL we give qemu time to to flush
all buffers and exit. Once qemu exits, we will see an EOF on monitor
connection and tear down the domain. In case qemu ignores SIGTERM or
just hangs there, the process stays running but that's not any different
from a possible hang anytime during the shutdown process so I think it's
just fine.

Also qemu (since 0.14 until it's fixed) has a bug in SIGTERM processing
which causes it not to exit but instead send new SHUTDOWN event and keep
waiting. I think the best we can do is to ignore duplicate SHUTDOWN
events to avoid a SHUTDOWN-SIGTERM loop and leave the domain in paused
state.
2011-09-16 17:21:10 +02:00
Eric Blake
5e47785b85 snapshot: only pass snapshot to qemu command line when reverting
Changing the current vm, and writing that change to the file
system, all before a new qemu starts, is risky; it's hard to
roll back if starting the new qemu fails for some reason.
Instead of abusing vm->current_snapshot and making the command
line generator decide whether the current snapshot warrants
using -loadvm, it is better to just directly pass a snapshot all
the way through the call chain if it is to be loaded.

This frees up the last use of snapshot->def->active for qemu's
use, so the next patch can repurpose that field for tracking
which snapshot is current.

* src/qemu/qemu_command.c (qemuBuildCommandLine): Don't use active
field of snapshot.
* src/qemu/qemu_process.c (qemuProcessStart): Add a parameter.
* src/qemu/qemu_process.h (qemuProcessStart): Update prototype.
* src/qemu/qemu_migration.c (qemuMigrationPrepareAny): Update
callers.
* src/qemu/qemu_driver.c (qemudDomainCreate)
(qemuDomainSaveImageStartVM, qemuDomainObjStart)
(qemuDomainRevertToSnapshot): Likewise.
(qemuDomainSnapshotSetCurrentActive)
(qemuDomainSnapshotSetCurrentInactive): Delete unused functions.
2011-08-25 15:07:57 -06:00
Eric Blake
193cd0f3c8 qemu: fix crash when mixing sync and async monitor jobs
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.
2011-08-01 09:41:57 -06:00
Daniel P. Berrange
109efd7941 Implement code to attach to external QEMU instances.
Given a PID, the QEMU driver reads /proc/$PID/cmdline and
/proc/$PID/environ to get the configuration. This is fed
into the ARGV->XML convertor to build an XML configuration
for the process.

/proc/$PID/exe is resolved to identify the full command
binary path

After checking for name/uuid uniqueness, an attempt is
made to connect to the monitor socket. If successful
then 'info status' and 'info kvm' are issued to determine
whether the CPUs are running and if KVM is enabled.

* src/qemu/qemu_driver.c: Implement virDomainQemuAttach
* src/qemu/qemu_process.h, src/qemu/qemu_process.c: Add
  qemuProcessAttach to connect to the monitor of an
  existing QEMU process
2011-07-12 15:39:04 +01:00