Generally, functions which return malloc'd strings should be typed
as 'char *', not 'const char *', to make it obvious that the caller
is responsible to free things. free(const char *) fails to compile,
and although we have a cast embedded in VIR_FREE to work around poor
code that frees const char *, it's better to not rely on that hack.
* src/qemu/qemu_driver.c (qemuDiskPathToAlias): Change return type.
(qemuDomainBlockJobImpl): Update caller.
Commit 89b6284f made it possible to pass either a source name or
the target device to most API demanding a disk designation, but
forgot to update the documentation. It also failed to update
virDomainBlockStats to take both forms. This patch fixes both the
documentation and the remaining function.
Xen continues to use just device shorthand (that is, I did not
implement path lookup there, since xen does not track a domain_conf
to quickly tie a path back to the device shorthand).
* src/libvirt.c (virDomainBlockStats, virDomainBlockStatsFlags)
(virDomainGetBlockInfo, virDomainBlockPeek)
(virDomainBlockJobAbort, virDomainGetBlockJobInfo)
(virDomainBlockJobSetSpeed, virDomainBlockPull): Document
acceptable disk naming conventions.
* src/qemu/qemu_driver.c (qemuDomainBlockStats)
(qemuDomainBlockStatsFlags): Allow lookup by source name.
* src/test/test_driver.c (testDomainBlockStats): Likewise.
Rename the macvtap.c file to virnetdevmacvlan.c to reflect its
functionality. Move the port profile association code out into
virnetdevvportprofile.c. Make the APIs available unconditionally
to callers
* src/util/macvtap.h: rename to src/util/virnetdevmacvlan.h,
* src/util/macvtap.c: rename to src/util/virnetdevmacvlan.c
* src/util/virnetdevvportprofile.c, src/util/virnetdevvportprofile.h:
Pull in vport association code
* src/Makefile.am, src/conf/domain_conf.h, src/qemu/qemu_conf.c,
src/qemu/qemu_conf.h, src/qemu/qemu_driver.c: Update include
paths & remove conditional compilation
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
Qemu will be the first driver to make use of a typed string in the
next round of additions. Separate out the trivial addition.
* src/qemu/qemu_driver.c (qemudSupportsFeature): Advertise feature.
(qemuDomainGetBlkioParameters, qemuDomainGetMemoryParameters)
(qemuGetSchedulerParametersFlags, qemudDomainBlockStatsFlags):
Allow typed strings flag where trivially supported.
The bridge management APIs in src/util/bridge.c require a brControl
object to be passed around. This holds the file descriptor for the
control socket. This extra object complicates use of the API for
only a minor efficiency gain, which is in turn entirely offset by
the need to fork/exec the brctl command for STP configuration.
This patch removes the 'brControl' object entirely, instead opening
the control socket & closing it again within the scope of each method.
The parameter names for the APIs are also made to consistently use
'brname' for bridge device name, and 'ifname' for an interface
device name. Finally annotations are added for non-NULL parameters
and return check validation
* src/util/bridge.c, src/util/bridge.h: Remove brControl object
and update API parameter names & annotations.
* src/lxc/lxc_driver.c, src/network/bridge_driver.c,
src/uml/uml_conf.h, src/uml/uml_conf.c, src/uml/uml_driver.c,
src/qemu/qemu_command.c, src/qemu/qemu_conf.h,
src/qemu/qemu_driver.c: Remove reference to 'brControl' object
While Xen only has a single paravirt console, UML, and
QEMU both support multiple paravirt consoles. The LXC
driver can also be trivially made to support multiple
consoles. This patch extends the XML to allow multiple
<console> elements in the XML. It also makes the UML
and QEMU drivers support this config.
* src/conf/domain_conf.c, src/conf/domain_conf.h: Allow
multiple <console> devices
* src/lxc/lxc_driver.c, src/xen/xen_driver.c,
src/xenxs/xen_sxpr.c, src/xenxs/xen_xm.c: Update for
internal API changes
* src/security/security_selinux.c, src/security/virt-aa-helper.c:
Only label consoles that aren't a copy of the serial device
* src/qemu/qemu_command.c, src/qemu/qemu_driver.c,
src/qemu/qemu_process.c, src/uml/uml_conf.c,
src/uml/uml_driver.c: Support multiple console devices
* tests/qemuxml2xmltest.c, tests/qemuxml2argvtest.c: Extra
tests for multiple virtio consoles. Set QEMU_CAPS_CHARDEV
for all console /channel tests
* tests/qemuxml2argvdata/qemuxml2argv-channel-virtio-auto.args,
tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args
tests/qemuxml2argvdata/qemuxml2argv-console-virtio.args: Update
for correct chardev syntax
* tests/qemuxml2argvdata/qemuxml2argv-console-virtio-many.args,
tests/qemuxml2argvdata/qemuxml2argv-console-virtio-many.xml: New
test file
Document the parameter names that will be used by
virDomain{Get,Set}SchedulerParameters{,Flags}, rather than
hard-coding those names in each driver, to match what is
done with memory, blkio, and blockstats parameters.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_SCHEDULER_CPU_SHARES)
(VIR_DOMAIN_SCHEDULER_VCPU_PERIOD)
(VIR_DOMAIN_SCHEDULER_VCPU_QUOTA, VIR_DOMAIN_SCHEDULER_WEIGHT)
(VIR_DOMAIN_SCHEDULER_CAP, VIR_DOMAIN_SCHEDULER_RESERVATION)
(VIR_DOMAIN_SCHEDULER_LIMIT, VIR_DOMAIN_SCHEDULER_SHARES): New
field name macros.
* src/qemu/qemu_driver.c (qemuSetSchedulerParametersFlags)
(qemuGetSchedulerParametersFlags): Use new defines.
* src/test/test_driver.c (testDomainGetSchedulerParamsFlags)
(testDomainSetSchedulerParamsFlags): Likewise.
* src/xen/xen_hypervisor.c (xenHypervisorGetSchedulerParameters)
(xenHypervisorSetSchedulerParameters): Likewise.
* src/xen/xend_internal.c (xenDaemonGetSchedulerParameters)
(xenDaemonSetSchedulerParameters): Likewise.
* src/lxc/lxc_driver.c (lxcSetSchedulerParametersFlags)
(lxcGetSchedulerParametersFlags): Likewise.
* src/esx/esx_driver.c (esxDomainGetSchedulerParametersFlags)
(esxDomainSetSchedulerParametersFlags): Likewise.
* src/libxl/libxl_driver.c (libxlDomainGetSchedulerParametersFlags)
(libxlDomainSetSchedulerParametersFlags): Likewise.
Since all virTypedParameter APIs allow us to return the number
of slots we actually populated, we should allow the user to
call with nparams too small (without overrunning their array)
or too large (ignoring the tail of the array that we can't fill),
rather than requiring that they get things exactly right.
Making this change will make it easier for a future patch to
introduce VIR_TYPED_PARAM_STRING, with filtering in libvirt.c
rather than in every single driver, since users already have
to be prepared for *nparams to be smaller on exit than on entry.
* src/qemu/qemu_driver.c (qemuDomainGetBlkioParameters)
(qemuDomainGetMemoryParameters): Allow variable nparams on entry.
(qemuGetSchedulerParametersFlags): Drop redundant check.
(qemudDomainBlockStats, qemudDomainBlockStatsFlags): Rename...
(qemuDomainBlockStats, qemuDomainBlockStatsFlags): ...to this.
Don't return unavailable stats.
The qemu RBD driver needs access to the conn in order to get the secret
needed for connecting to the ceph cluster.
Signed-off-by: Sage Weil <sage@newdream.net>
The QEMU monitor command 'add_client' can be used to connect to
a VNC or SPICE graphics display. This allows for implementation
of the virDomainOpenGraphics API
* src/qemu/qemu_driver.c: Implement virDomainOpenGraphics
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
Add binding for 'add_client' command
Rather than making all clients of monitor commands that are JSON-only
check whether yajl support was compiled in, it is simpler to just
avoid setting the capability bit up front if we can't use the capability.
* src/qemu/qemu_capabilities.c (qemuCapsComputeCmdFlags): Only set
capability bit if we also have yajl library to use it.
* src/qemu/qemu_driver.c (qemuDomainReboot): Drop #ifdefs.
* src/qemu/qemu_process.c (qemuProcessStart): Likewise.
* tests/qemuhelptest.c (testHelpStrParsing): Pass test even
without yajl.
* tests/qemuxml2argvtest.c (mymain): Simplify use of json flag.
* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-error-*.args:
Update expected results to match.
This patch is rather cosmetic as it only moves device alias
assignation from command line construction just before that.
However, it is needed in connotation of previous and next patch.
The improvements to virBuffer, along with a paradigm shift to pass
the original buffer through rather than creating a second buffer,
allow us to shave off quite a few lines of code.
* src/util/sysinfo.h (virSysinfoFormat): Alter signature.
* src/util/sysinfo.c (virSysinfoFormat, virSysinfoBIOSFormat)
(virSysinfoSystemFormat, virSysinfoProcessorFormat)
(virSysinfoMemoryFormat): Change indentation parameter.
* src/conf/domain_conf.c (virDomainSysinfoDefFormat): Adjust
caller.
* src/qemu/qemu_driver.c (qemuGetSysinfo): Likewise.
There is a little difference between the output of domxml-to-native and the actual commandline.
No matter qemu is in control or readline mode, domxml-to-native always converts it to readline mode.
That is because the parameter "monitor_json" for qemuBuildCommandLine() is always set to false
in qemuDomainXMLToNative().
Signed-off-by: tangchen <tangchen@cn.fujitsu.com>
Noticed when testing new libvirt against old qemu that lacked the
snapshot_blkdev HMP command. Libvirt was mistakenly treating the
command as successful, and re-writing the domain XML to use the
just-created 0-byte file, rendering the domain broken on restart.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextDiskSnapshot):
Notice another possible error message.
* src/qemu/qemu_driver.c
(qemuDomainSnapshotCreateSingleDiskActive): Don't keep 0-byte file
on failure.
As this is needed. Although some functions check for domain
being active before obtaining job, we need to check it after,
because obtaining job unlocks domain object, during which
a state of domain can be changed.
This patch extends qemudDomainCoreDump so it supports new VIR_DUMP_RESET
flag. If this flag is set, domain is reset on successful dump. However,
this is needed to be done after we start CPUs.
With the recent refactoring of qemu snapshot relationships, it
is now trivial to filter on leaves.
* src/conf/domain_conf.c (virDomainSnapshotObjListCount)
(virDomainSnapshotObjListCopyNames): Handle new flag.
* src/qemu/qemu_driver.c (qemuDomainSnapshotListNames)
(qemuDomainSnapshotNum, qemuDomainSnapshotListChildrenNames)
(qemuDomainSnapshotNumChildren): Pass new flag through.
The previous optimizations lead to some follow-on cleanups.
* src/conf/domain_conf.c (virDomainSnapshotForEachChild)
(virDomainSnapshotForEachDescendant): Drop dead parameter.
(virDomainSnapshotActOnDescendant)
(virDomainSnapshotObjListNumFrom)
(virDomainSnapshotObjListGetNamesFrom): Update callers.
* src/qemu/qemu_driver.c (qemuDomainSnapshotNumChildren)
(qemuDomainSnapshotListChildrenNames, qemuDomainSnapshotDelete):
Likewise.
* src/conf/domain_conf.h: Update prototypes.
Maintain the parent/child relationships of all qemu snapshots.
* src/qemu/qemu_driver.c (qemuDomainSnapshotLoad): Populate
relationships after loading.
(qemuDomainSnapshotCreateXML): Set relations on creation; tweak
redefinition to reuse existing object.
(qemuDomainSnapshotReparentChildren, qemuDomainSnapshotDelete):
Clear relations on delete.
Not too hard to wire up. The trickiest part is realizing that
listing children of a snapshot cannot use SNAPSHOT_LIST_ROOTS,
and that we overloaded that bit to also mean SNAPSHOT_LIST_DESCENDANTS;
we use that bit to decide which iteration to use, but don't want
the existing counting/listing functions to see that bit.
* src/conf/domain_conf.h (virDomainSnapshotObjListNumFrom)
(virDomainSnapshotObjListGetNamesFrom): New prototypes.
* src/conf/domain_conf.c (virDomainSnapshotObjListNumFrom)
(virDomainSnapshotObjListGetNamesFrom): New functions.
* src/libvirt_private.syms (domain_conf.h): Export them.
* src/qemu/qemu_driver.c (qemuDomainSnapshotNumChildren)
(qemuDomainSnapshotListChildrenNames): New functions.
If parsing qemu command line fails (e.g. because of non-existing
process number supplied), we jump to cleanup label where we free
pidfile. Therefore it needs to be initialized. Otherwise we free
random pointer.
Implements the documentation for snapshot revert vs. force.
Part of the patch tightens existing behavior (previously, reverting
to an old snapshot without <domain> was blindly attempted, now it
requires force), while part of it relaxes behavior (previously, it
was not possible to revert an active domain to an ABI-incompatible
active snapshot, now force allows this transition).
* src/qemu/qemu_driver.c (qemuDomainRevertToSnapshot): Check for
risky situations, and allow force to get past them.
Qemu driver tries to update balloon data in virDomainGetInfo and if it
can't do so because there is another monitor job running, it just
reports what's known in domain def. However, if there was no job running
but getting the data from qemu fails, we would fail the whole API. This
doesn't make sense. Let's make the failure nonfatal.
Currently, qemuDomainGetXMLDesc and qemudDomainGetInfo check for
outstanding synchronous job before (eventual) monitor entering.
However, there can be already async job set, e.g. migration.
If the daemon is restarted so we reconnect to monitor, cdrom media
can be ejected. In that case we don't want to show it in domain xml,
or require it on migration destination.
To check for disk status use 'info block' monitor command.
First hypervisor implementation of the new API.
Allows 'virsh snapshot-list --tree' to be more efficient.
* src/qemu/qemu_driver.c (qemuDomainSnapshotGetParent): New
function.
Commit 282fe1f0 documented that transient domains will auto-delete
any snapshot metadata when the last reference to the domain is
removed, and that management apps are in charge of grabbing any
snapshot metadata prior to that point. However, this was not
actually implemented for qemu until now.
* src/qemu/qemu_driver.c (qemudDomainCreate)
(qemuDomainDestroyFlags, qemuDomainSaveInternal)
(qemudDomainCoreDump, qemuDomainRestoreFlags, qemudDomainDefine)
(qemuDomainUndefineFlags, qemuDomainMigrateConfirm3)
(qemuDomainRevertToSnapshot): Clean up snapshot metadata.
* src/qemu/qemu_migration.c (qemuMigrationPrepareAny)
(qemuMigrationPerformJob, qemuMigrationPerformPhase)
(qemuMigrationFinish): Likewise.
* src/qemu/qemu_process.c (qemuProcessHandleMonitorEOF)
(qemuProcessReconnect, qemuProcessReconnectHelper)
(qemuProcessAutoDestroyDom): Likewise.
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.
Commit 19f8c98 introduced VIR_DOMAIN_UNDEFINE_SNAPSHOTS_METADATA,
with the intent that omitting the flag makes undefine fail, and
including the flag deletes metadata. But it used the wrong logic.
Also, hoist the transient domain sooner, so that we don't
accidentally remove metadata of a transient domain.
* src/qemu/qemu_driver.c (qemuDomainUndefineFlags): Check correct
flag value.
The commit that prevents disk corruption on domain shutdown
(96fc478417) causes regression with QEMU
0.14.* and 0.15.* because of a regression bug in QEMU that was fixed
only recently in QEMU git. The affected versions of QEMU do not quit on
SIGTERM if started with -no-shutdown, which we use to implement fake
reboot. Since -no-shutdown tells QEMU not to quit automatically on guest
shutdown, domains started using the affected QEMU cannot be shutdown
properly and stay in a paused state.
This patch disables fake reboot feature on such QEMU by not using
-no-shutdown, which makes shutdown work as expected. However,
virDomainReboot will not work in this case and it will report "Requested
operation is not valid: Reboot is not supported with this QEMU binary".
Virsh man page lists driver types to be used with attach-device
command, but does not specify that those are usable only with the XEN
Hypervisor.
This patch adds statement, that those options specified are applicable
only on the Xen hypervisor and adds option usable with qemu emulator.
This patch also changes type of error returned by QEMU driver if the
user specifies incompatible driver type from VIR_ERR_INTERNAL_ERROR to
VIR_ERR_CONFIG_UNSUPPORTED.
For all types of disks other than qcow2, we were requesting that
SELinux labeling visit the new file as if it were qcow2, which
means labeling would try to find the backing files of an empty file.
And for a pre-existing qcow2 disk, we were passing NULL, which meant
that labelling tried to probe the file type (and if probing is
disabled, per the default qemu.conf, this made snapshots fail).
What we really want is to make SELinux labeling visit the new
file as raw; it will later be converted to qcow2 if qemu successfully
made the snapshot.
* src/qemu/qemu_driver.c
(qemuDomainSnapshotCreateSingleDiskActive): Force SELinux labeling
to avoid probe of new file.
For external snapshots to be useful on persistent domains, we must
alter the persistent definition alongside the running definition.
Thanks to the possibility of disk hotplug as well as of edits that
only affect the persistent xml, we can't assume that vm->def and
vm->newDef have the same disk at the same index, so we can only
update the persistent copy if the device destination matches up.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateDiskActive)
(qemuDomainSnapshotCreateSingleDiskActive): Also affect newDef, if
present.
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.
Now that migration speed is stored in qemuDomainObjPrivate structure,
save the new value when invoking qemuDomainMigrateSetMaxSpeed().
Allow setting migration speed on inactive domain too.
Regression introduced in commit 3881a470, due to an improper rebase
of a cleanup written beforehand but only applied after a rebased of
a refactoring that created a new function in commit 25fb3ef.
Also avoids passing NULL to printf %s.
* src/qemu/qemu_driver.c: In qemuDomainSnapshotForEachQcow2()
it free up the memory of qemu_driver->qemuImgBinary in the
cleanup tag which leads to the garbage value of qemuImgBinary
in qemu_driver struct and libvirtd crash when running
"virsh snapshot-create" command a second time.
Signed-off-by: Eric Blake <eblake@redhat.com>
Regression introduced in commit 89b6284fd, due to an incorrect
conversion to the new means of converting disk names back to
the correct object.
* src/qemu/qemu_driver.c (qemuDomainGetBlockInfo): Avoid NULL deref.
This patch enables modifying network device configuration using the
virUpdateDeviceFlags API method. Matching of devices is accomplished
using MAC addresses.
While updating live configuration of a running domain, the user is
allowed only to change link state of the interface. Additional
modifications may be added later. For now the code checks for
unsupported changes and thereafter changes the link state, if
applicable.
When updating persistent configuration of guest's network interface the
whole configuration (except for the MAC address) may be modified and
is stored for the next startup.
* src/qemu/qemu_driver.c - Add dispatching of virUpdateDevice for
network devices update (live/config)
* src/qemu/qemu_hotplug.c - add setting of initial link state on live
device addition
- add function to change network device
configuration. By now it supports only
changing of link state
* src/qemu/qemu_hotplug.h - Headers to above functions
* src/qemu/qemu_process.c - set link states before virtual machine
start. Qemu does not support setting of
this on the command line.
The mainly changes are:
1) Update qemuMonitorGetBlockStatsInfo and it's children (Text/JSON)
functions to return the value of new latency fields.
2) Add new function qemuMonitorGetBlockStatsParamsNumber, which is
to count how many parameters the underlying QEMU supports.
3) Update virDomainBlockStats in src/qemu/qemu_driver.c to be
compatible with the changes by 1).
If libvirt daemon gets restarted and there is (at least) one
unresponsive qemu, the startup procedure hangs up. This patch creates
one thread per vm in which we try to reconnect to monitor. Therefore,
blocking in one thread will not affect other APIs.
This patch annotates APIs with low or high priority.
In low set MUST be all APIs which might eventually access monitor
(and thus block indefinitely). Other APIs may be marked as high
priority. However, some must be (e.g. domainDestroy).
For high priority calls (HPC), there are some high priority workers
(HPW) created in the pool. HPW can execute only HPC, although normal
worker can process any call regardless priority. Therefore, only those
APIs which are guaranteed to end in reasonable small amount of time
can be marked as HPC.
The size of this HPC pool is static, because HPC are expected to end
quickly, therefore jobs assigned to this pool will be served quickly.
It can be configured in libvirtd.conf via prio_workers variable.
Default is set to 5.
To mark API with low or high priority, append priority:{low|high} to
it's comment in src/remote/remote_protocol.x. This is similar to
autogen|skipgen. If not marked, the generator assumes low as default.
With this, it is now possible to create external snapshots even
when SELinux is enforcing, and to protect the new file with a
lock manager.
* src/qemu/qemu_driver.c
(qemuDomainSnapshotCreateSingleDiskActive): Create and register
new file with proper permissions and locks.
(qemuDomainSnapshotCreateDiskActive): Update caller.
Lots of earlier patches led up to this point - the qemu snapshot_blkdev
monitor command can now be controlled by libvirt! Well, insofar as
SELinux doesn't prevent qemu from open(O_CREAT) on the files. There's
still some followup work before things work with SELinux enforcing,
but this patch is big enough to post now.
There's still room for other improvements, too (for example, taking a
disk snapshot of an inactive domain, by using qemu-img for both internal
and external snapshots; wiring up delete and revert control, including
additional flags from my RFC; supporting active QED disk snapshots;
supporting per-storage-volume snapshots such as LVM or btrfs snapshots;
etc.). But this patch is the one that proves the new XML works!
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): Wire in
active disk snapshots.
(qemuDomainSnapshotDiskPrepare)
(qemuDomainSnapshotCreateDiskActive)
(qemuDomainSnapshotCreateSingleDiskActive): New functions.
My RFC for snapshot support [1] proposes several rules for when it is
safe to delete or revert to an external snapshot, predicated on
the existence of new API flags. These will be incrementally added
in future patches, but until then, blindly mishandling a disk
snapshot risks corrupting internal state, so it is better to
outright reject the attempts until the other pieces are in place,
thus incrementally relaxing the restrictions added in this patch.
[1] https://www.redhat.com/archives/libvir-list/2011-August/msg00361.html
* src/qemu/qemu_driver.c (qemuDomainSnapshotCountExternal): New
function.
(qemuDomainUndefineFlags, qemuDomainSnapshotDelete): Use it to add
safety valve.
(qemuDomainRevertToSnapshot, qemuDomainSnapshotCreateXML): Add safety
valve.
Prior to this patch, <domainsnapshot>/<disks> was ignored. This
changes it to be an error unless an explicit disk snapshot is
requested (a future patch may relax things if it turns out to
be useful to have a <disks> specification alongside a system
checkpoint).
* include/libvirt/libvirt.h.in
(VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY): New flag.
* src/libvirt.c (virDomainSnapshotCreateXML): Document it.
* src/esx/esx_driver.c (esxDomainSnapshotCreateXML): Disk
snapshots not supported yet.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotCreateXML): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): Likewise.
I got confused when 'virsh domblkinfo dom disk' required the
path to a disk (which can be ambiguous, since a single file
can back multiple disks), rather than the unambiguous target
device name that I was using in disk snapshots. So, in true
developer fashion, I went for the best of both worlds - all
interfaces that operate on a disk (aka block) now accept
either the target name or the unambiguous path to the backing
file used by the disk.
* src/conf/domain_conf.h (virDomainDiskIndexByName): Add
parameter.
(virDomainDiskPathByName): New prototype.
* src/libvirt_private.syms (domain_conf.h): Export it.
* src/conf/domain_conf.c (virDomainDiskIndexByName): Also allow
searching by path, and decide whether ambiguity is okay.
(virDomainDiskPathByName): New function.
(virDomainDiskRemoveByName, virDomainSnapshotAlignDisks): Update
callers.
* src/qemu/qemu_driver.c (qemudDomainBlockPeek)
(qemuDomainAttachDeviceConfig, qemuDomainUpdateDeviceConfig)
(qemuDomainGetBlockInfo, qemuDiskPathToAlias): Likewise.
* src/qemu/qemu_process.c (qemuProcessFindDomainDiskByPath):
Likewise.
* src/libxl/libxl_driver.c (libxlDomainAttachDeviceDiskLive)
(libxlDomainDetachDeviceDiskLive, libxlDomainAttachDeviceConfig)
(libxlDomainUpdateDeviceConfig): Likewise.
* src/uml/uml_driver.c (umlDomainBlockPeek): Likewise.
* src/xen/xend_internal.c (xenDaemonDomainBlockPeek): Likewise.
* docs/formatsnapshot.html.in: Update documentation.
* tools/virsh.pod (domblkstat, domblkinfo): Likewise.
* docs/schemas/domaincommon.rng (diskTarget): Tighten pattern on
disk targets.
* docs/schemas/domainsnapshot.rng (disksnapshot): Update to match.
* tests/domainsnapshotxml2xmlin/disk_snapshot.xml: Update test.
Since a snapshot is fully recoverable, it is useful to have a
snapshot as a means of hibernating a guest, then reverting to
the snapshot to wake the guest up. This mode of usage is
similar to 'virsh save/virsh restore', except that virsh
save uses an external file while virsh snapshot keeps the
vm state internal to a qcow2 file. However, it only works on
persistent domains.
In the usage pattern of snapshot/revert for hibernating a guest,
there is no need to keep the guest running between the two points
in time, especially since that would generate runtime state that
would just be discarded. Add a flag to make it possible to
stop the domain after the snapshot has completed.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_CREATE_HALT):
New flag.
* src/libvirt.c (virDomainSnapshotCreateXML): Document it.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML)
(qemuDomainSnapshotCreateActive): Implement it.
Reverting to a state prior to an external snapshot risks
corrupting any other branches in the snapshot hierarchy that
were using the snapshot as a read-only backing file. So
disk snapshot code will default to preventing reverting to
a snapshot that has any children, meaning that deleting just
the children of a snapshot becomes a useful operation in
preparing that snapshot for being a future reversion target.
The code for the new flag is simple - it's one less deletion,
plus a tweak to keep the current snapshot correct.
* include/libvirt/libvirt.h.in
(VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY): New flag.
* src/libvirt.c (virDomainSnapshotDelete): Document it, and
enforce mutual exclusion.
* src/qemu/qemu_driver.c (qemuDomainSnapshotDelete): Implement
it.
When reverting to a snapshot, the inactive domain configuration
has to be rolled back to what it was at the time of the snapshot.
Additionally, if the VM is active and the snapshot was active,
this now adds a failure if the two configurations are ABI
incompatible, rather than risking qemu confusion.
A future patch will add a VIR_DOMAIN_SNAPSHOT_FORCE flag, which
will be required for two risky code paths - reverting to an
older snapshot that lacked full domain information, and reverting
from running to a live snapshot that requires starting a new qemu
process. Any reverting that stops a running vm is also a form
of data loss (discarding the current running state to go back in
time), but as that is what reversion usually implies, it is
probably not worth requiring a force flag.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): Copy out
domain.
(qemuDomainSnapshotCreateXML, qemuDomainRevertToSnapshot): Perform
ABI compatibility checks.
Just like VM saved state images (virsh save), snapshots MUST
track the inactive domain xml to detect any ABI incompatibilities.
The indentation is not perfect, but functionality comes before form.
Later patches will actually supply a full domain; for now, this
wires up the storage to support one, but doesn't ever generate one
in dumpxml output.
Happily, libvirt.c was already rejecting use of VIR_DOMAIN_XML_SECURE
from read-only connections, even though before this patch, there was
no information to be secured by the use of that flag.
And while we're at it, mark the libvirt snapshot metadata files
as internal-use only.
* src/libvirt.c (virDomainSnapshotGetXMLDesc): Document flag.
* src/conf/domain_conf.h (_virDomainSnapshotDef): Add member.
(virDomainSnapshotDefParseString, virDomainSnapshotDefFormat):
Update signature.
* src/conf/domain_conf.c (virDomainSnapshotDefFree): Clean up.
(virDomainSnapshotDefParseString): Optionally parse domain.
(virDomainSnapshotDefFormat): Output full domain.
* src/esx/esx_driver.c (esxDomainSnapshotCreateXML)
(esxDomainSnapshotGetXMLDesc): Update callers.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotCreateXML)
(vboxDomainSnapshotGetXMLDesc): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML)
(qemuDomainSnapshotLoad, qemuDomainSnapshotGetXMLDesc)
(qemuDomainSnapshotWriteMetadata): Likewise.
* docs/formatsnapshot.html.in: Rework doc example.
Based on a patch by Philipp Hahn.
A nice benefit of deleting all snapshots at undefine time is that
you don't have to do any reparenting or subtree identification - since
everything goes, this is an O(n) process, whereas using multiple
virDomainSnapshotDelete calls would be O(n^2) or worse. But it is
only doable for snapshot metadata, where we are in control of the
data being deleted; for the actual snapshots, there's too much
likelihood of something going wrong, and requiring even more API
calls to figure out what failed in the meantime, so callers are
better off deleting the snapshot data themselves one snapshot at
a time where they can deal with failures as they happen.
* src/qemu/qemu_driver.c (qemuDomainUndefineFlags): Honor new flags.
As more clients start to want to know this information, doing
a PATH stat walk and malloc for every client adds up.
We are only caching the location, not the capabilities, so even
if qemu-img is updated in the meantime, it will still probably
live in the same location. So there is no need to worry about
clearing this particular cache.
* src/qemu/qemu_conf.h (qemud_driver): Add member.
* src/qemu/qemu_driver.c (qemudShutdown): Cleanup.
(qemuFindQemuImgBinary): Add an argument, and cache result.
(qemuDomainSnapshotForEachQcow2, qemuDomainSnapshotDiscard)
(qemuDomainSnapshotCreateInactive, qemuDomainSnapshotRevertInactive)
(qemuDomainSnapshotCreateXML, qemuDomainRevertToSnapshot): Update
callers.
Just as leaving managed save metadata behind can cause problems
when creating a new domain that happens to collide with the name
of the just-deleted domain, the same is true of leaving any
snapshot metadata behind. For safety sake, extend the semantic
change of commit b26a9fa9 to also cover snapshot metadata as a
reason to reject undefining an inactive domain. A future patch
will make sure that shutdown of a transient domain automatically
deletes snapshot metadata (whether by destroy, shutdown, or
guest-initiated action). Management apps of transient domains
should take care to capture xml of snapshots, if it is necessary
to recreate the snapshot metadata on a later transient domain
with the same name and uuid.
This also documents a new flag that hypervisors can choose to
support as a shortcut for taking care of the metadata as part of
the undefine process; however, nontrivial driver support for these
flags will be deferred to future patches.
Note that ESX and VBox can never be transient; therefore, they
do not have to worry about automatic cleanup after shutdown
(the persistent domain still remains); likewise they never
store snapshot metadata, so the undefine flag is trivial.
The nontrivial work remaining is thus in the qemu driver.
* include/libvirt/libvirt.h.in
(VIR_DOMAIN_UNDEFINE_SNAPSHOTS_METADATA): New flag.
* src/libvirt.c (virDomainUndefine, virDomainUndefineFlags):
Document new limitations and flag.
* src/esx/esx_driver.c (esxDomainUndefineFlags): Trivial
implementation.
* src/vbox/vbox_tmpl.c (vboxDomainUndefineFlags): Likewise.
* src/qemu/qemu_driver.c (qemuDomainUndefineFlags): Enforce
the limitations.
Redefining a qemu snapshot requires a bit of a tweak to the common
snapshot parsing code, but the end result is quite nice.
Be careful that redefinitions do not introduce circular parent
chains. Also, we don't want to allow conversion between online
and offline existing snapshots. We could probably do some more
validation for snapshots that don't already exist to make sure
they are even feasible, by parsing qemu-img output, but that
can come later.
* src/conf/domain_conf.h (virDomainSnapshotParseFlags): New
internal flags.
* src/conf/domain_conf.c (virDomainSnapshotDefParseString): Alter
signature to take internal flags.
* src/esx/esx_driver.c (esxDomainSnapshotCreateXML): Update caller.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotCreateXML): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): Support
new public flags.
Supporting NO_METADATA on snapshot creation is interesting - we must
still return a valid opaque snapshot object, but the user can't get
anything out of it (unless we add a virDomainSnapshotGetName()),
since it is no longer registered with the domain.
Also, virsh now tries to query for secure xml, in anticipation of
when we store <domain> xml inside <domainsnapshot>; for now, we
can trivially support it, since we have nothing secure.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): Support
new flag.
(qemuDomainSnapshotGetXMLDesc): Trivially support VIR_DOMAIN_XML_SECURE.
To make it easier to know when undefine will fail because of existing
snapshot metadata, we need to know how many snapshots have metadata.
Also, it is handy to filter the list of snapshots to just those that
have no parents; document that flag now, but implement it in later patches.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_LIST_ROOTS)
(VIR_DOMAIN_SNAPSHOT_LIST_METADATA): New flags.
* src/libvirt.c (virDomainSnapshotNum)
(virDomainSnapshotListNames): Document them.
* src/esx/esx_driver.c (esxDomainSnapshotNum)
(esxDomainSnapshotListNames): Implement trivial flag.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotNum)
(vboxDomainSnapshotListNames): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotNum)
(qemuDomainSnapshotListNames): Likewise.
Adding this was trivial compared to the previous patch for fixing
qemu snapshot deletion in the first place.
* src/qemu/qemu_driver.c (qemuDomainSnapshotDiscard): Add
parameter.
(qemuDomainSnapshotDiscardDescendant, qemuDomainSnapshotDelete):
Update callers.
Similar to the last patch in isolating the filtering from the
client actions, so that clients don't have to reinvent the
filtering.
* src/conf/domain_conf.h (virDomainSnapshotForEachChild): New
prototype.
* src/libvirt_private.syms (domain_conf.h): Export it.
* src/conf/domain_conf.c (virDomainSnapshotActOnChild)
(virDomainSnapshotForEachChild): New functions.
(virDomainSnapshotCountChildren): Delete.
(virDomainSnapshotHasChildren): Simplify.
* src/qemu/qemu_driver.c (qemuDomainSnapshotReparentChildren)
(qemuDomainSnapshotDelete): Likewise.
Deleting a snapshot and all its descendants had problems with
tracking the current snapshot. The deletion does not necessarily
proceed in depth-first order, so a parent could be deleted
before a child, wreaking havoc on passing the notion of the
current snapshot to the parent. Furthermore, even if traversal
were depth-first, doing multiple file writes to pass current up
the chain one snapshot at a time is wasteful, comparing to a
single update to the current snapshot at the end of the algorithm.
* src/qemu/qemu_driver.c (snap_remove): Add field.
(qemuDomainSnapshotDiscard): Add parameter.
(qemuDomainSnapshotDiscardDescendant): Adjust accordingly.
(qemuDomainSnapshotDelete): Properly reset current.
This one's nasty. Ever since we fixed virHashForEach to prevent
nested hash iterations for safety reasons (commit fba550f6),
virDomainSnapshotDelete with VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN
has been broken for qemu: it deletes children, while leaving
grandchildren intact but pointing to a no-longer-present parent.
But even before then, the code would often appear to succeed to
clean up grandchildren, but risked memory corruption if you have
a large and deep hierarchy of snapshots.
For acting on just children, a single virHashForEach is sufficient.
But for acting on an entire subtree, it requires iteration; and
since we declared recursion as invalid, we have to switch to a
while loop. Doing this correctly requires quite a bit of overhaul,
so I added a new helper function to isolate the algorithm from the
actions, so that callers do not have to reinvent the iteration.
Note that this _still_ does not handle CHILDREN correctly if one
of the children is the current snapshot; that will be next.
* src/conf/domain_conf.h (_virDomainSnapshotDef): Add mark.
(virDomainSnapshotForEachDescendant): New prototype.
* src/libvirt_private.syms (domain_conf.h): Export it.
* src/conf/domain_conf.c (virDomainSnapshotMarkDescendant)
(virDomainSnapshotActOnDescendant)
(virDomainSnapshotForEachDescendant): New functions.
* src/qemu/qemu_driver.c (qemuDomainSnapshotDiscardChildren):
Replace...
(qemuDomainSnapshotDiscardDescenent): ...with callback that
doesn't nest hash traversal.
(qemuDomainSnapshotDelete): Use new function.
For a system checkpoint of a running or paused domain, it's fairly
easy to honor new flags for altering which state to use after the
revert. For an inactive snapshot, the revert has to be done while
there is no qemu process, so do back-to-back transitions; this also
lets us revert to inactive snapshots even for transient domains.
* src/qemu/qemu_driver.c (qemuDomainRevertToSnapshot): Support new
flags.
Commit 5e47785 broke reverts to offline system checkpoint snapshots
with older qemu, since there is no longer any code path to use
qemu -loadvm on next boot. Meanwhile, reverts to offline system
checkpoints have been broken for newer qemu, both before and
after that commit, since -loadvm no longer works to revert to
disk state without accompanying vm state. Fix both of these by
using qemu-img to revert disk state.
Meanwhile, consolidate the (now 3) clients of a qemu-img iteration
over all disks of a VM into one function, so that any future
algorithmic fixes to the FIXMEs in that function after partial
loop iterations are dealt with at once. That does mean that this
patch doesn't handle partial reverts very well, but we're not
making the situation any worse in this patch.
* src/qemu/qemu_driver.c (qemuDomainRevertToSnapshot): Use
qemu-img rather than 'qemu -loadvm' to revert to offline snapshot.
(qemuDomainSnapshotRevertInactive): New helper.
(qemuDomainSnapshotCreateInactive): Factor guts...
(qemuDomainSnapshotForEachQcow2): ...into new helper.
(qemuDomainSnapshotDiscard): Use it.
If you take a checkpoint snapshot of a running domain, then pause
qemu, then restore the snapshot, the result should be a running
domain, but the code was leaving things paused. Furthermore, if
you take a checkpoint of a paused domain, then run, then restore,
there was a brief but non-deterministic window of time where the
domain was running rather than paused. Fix both of these
discrepancies by always pausing before restoring.
Also, check that the VM is active every time lock is dropped
between two monitor calls.
Finally, straighten out the events that get emitted on each
transition.
* src/qemu/qemu_driver.c (qemuDomainRevertToSnapshot): Always
pause before reversion, and improve events.
Implement the new running/paused overrides for saved state management.
Unfortunately, for virDomainSaveImageDefineXML, the saved state
updates are write-only - I don't know of any way to expose a way
to query the current run/pause setting of an existing save image
file to the user without adding a new API or modifying the domain
xml of virDomainSaveImageGetXMLDesc to include a new element to
reflect the state bit encoded into the save image. However, I
don't think this is a show-stopper, since the API is designed to
leave the state bit alone unless an explicit flag is used to
change it.
* src/qemu/qemu_driver.c (qemuDomainSaveInternal)
(qemuDomainSaveImageOpen): Adjust signature.
(qemuDomainSaveFlags, qemuDomainManagedSave)
(qemuDomainRestoreFlags, qemuDomainSaveImageGetXMLDesc)
(qemuDomainSaveImageDefineXML, qemuDomainObjRestore): Adjust
callers.
There are two classes of management apps that track events - one
that only cares about on/off (and only needs to track EVENT_STARTED
and EVENT_STOPPED), and one that cares about paused/running (also
tracks EVENT_SUSPENDED/EVENT_RESUMED). To keep both classes happy,
any transition that can go from inactive to paused must emit two
back-to-back events - one for started and one for suspended (since
later resuming of the domain will only send RESUMED, but the first
class isn't tracking that).
This also fixes a bug where virDomainCreateWithFlags with the
VIR_DOMAIN_START_PAUSED flag failed to start paused when restoring
from a managed save image.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_EVENT_SUSPENDED_RESTORED)
(VIR_DOMAIN_EVENT_SUSPENDED_FROM_SNAPSHOT)
(VIR_DOMAIN_EVENT_RESUMED_FROM_SNAPSHOT): New sub-events.
* src/qemu/qemu_driver.c (qemuDomainRevertToSnapshot): Use them.
(qemuDomainSaveImageStartVM): Likewise, and add parameter.
(qemudDomainCreate, qemuDomainObjStart): Send suspended event when
starting paused.
(qemuDomainObjRestore): Add parameter.
(qemuDomainObjStart, qemuDomainRestoreFlags): Update callers.
* examples/domain-events/events-c/event-test.c
(eventDetailToString): Map new detail strings.
Commit 6766ff10 introduced a corner case bug with snapshot creation:
if a snapshot is created, but then we hit OOM while trying to
create the return value of the function, then we have polluted the
internal directory with the snapshot metadata with no way to clean
it up from the running libvirtd.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): Don't
write metadata file on OOM condition.
Several users have reported problems with 'virsh start' failing because
it was encountering a managed save situation where the managed save file
was incomplete. Be more robust to this by using two different magic
numbers, so that newer libvirt can gracefully handle an incomplete file
differently than a complete one, while older libvirt will at least fail
up front rather than trying to load only to have qemu fail at the end.
Managed save is a convenience - it exists to preserve as much state
as possible; if the state was not preserved, it is reasonable to just
log that fact, then proceed with a fresh boot. On the other hand,
user saves are under user control, so we must fail, but by making
the failure message distinct, the user can better decide how to handle
the situation of an incomplete save file.
* src/qemu/qemu_driver.c (QEMUD_SAVE_PARTIAL): New define.
(qemuDomainSaveInternal): Use it to mark incomplete images.
(qemuDomainSaveImageOpen, qemuDomainObjRestore): Add parameter
that controls what to do with partial images.
(qemuDomainRestoreFlags, qemuDomainSaveImageGetXMLDesc)
(qemuDomainSaveImageDefineXML, qemuDomainObjStart): Update callers.
Based on an initial idea by Osier Yang.
In a SELinux or root-squashing NFS environment, libvirt has to go
through some hoops to create a new file that qemu can then open()
by name. Snapshots are a case where we want to guarantee an empty
file that qemu can open; also, reopening a save file to convert it
from being marked partial to complete requires a reopen to avoid
O_DIRECT headaches. Refactor some existing code to make it easier
to reuse in later patches.
* src/qemu/qemu_migration.h (qemuMigrationToFile): Drop parameter.
* src/qemu/qemu_migration.c (qemuMigrationToFile): Let cgroup do
the stat, rather than asking caller to do it and pass info down.
* src/qemu/qemu_driver.c (qemuOpenFile): New function, pulled from...
(qemuDomainSaveInternal): ...here.
(doCoreDump, qemuDomainSaveImageOpen): Use it here as well.
The libvirt BlockPull API supports the use of an initial bandwidth limit but the
qemu block_stream API does not. To get the desired behavior we use the two APIs
strung together: first BlockPull, then BlockJobSetSpeed. We can do this at the
driver level to avoid duplicated code in each monitor path.
Signed-off-by: Adam Litke <agl@us.ibm.com>
There is no reason to forbid pausing an autodestroy domain
(not to mention that 'virsh start --paused --autodestroy'
succeeds in creating a paused autodestroy domain).
Meanwhile, qemu was failing to enforce the API documentation that
autodestroy domains cannot be saved. And while the original
documentation only mentioned save/restore, snapshots are another
form of saving that are close enough in semantics as to make no
sense on one-shot domains.
* src/qemu/qemu_driver.c (qemudDomainSuspend): Drop bogus check.
(qemuDomainSaveInternal, qemuDomainSnapshotCreateXML): Forbid
saves of autodestroy domains.
* src/libvirt.c (virDomainCreateWithFlags, virDomainCreateXML):
Document snapshot interaction.
There have been several instances of people having problems with
a broken managed save file, and not aware that they could use
'virsh managedsave-remove dom' to fix things. Making it possible
to do this as part of starting a domain makes the same functionality
easier to find, and one less API call.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_START_FORCE_BOOT): New
flag.
* src/libvirt.c (virDomainCreateWithFlags): Document it.
* src/qemu/qemu_driver.c (qemuDomainObjStart): Alter signature.
(qemuAutostartDomain, qemuDomainStartWithFlags): Update callers.
* tools/virsh.c (cmdStart): Expose it in virsh.
* tools/virsh.pod (start): Document it.
The QEMU 'sendkey' command expects keys to be encoded in the same
way as the RFB extended keycode set. Specifically it wants extended
keys to have the high bit of the first byte set, while the Linux
XT KBD driver codeset uses the low bit of the second byte. To deal
with this we introduce a new keymap 'RFB' and use that in the QEMU
driver
* include/libvirt/libvirt.h.in: Add VIR_KEYCODE_SET_RFB
* src/qemu/qemu_driver.c: Use RFB keycode set instead of XT KBD
* src/util/virkeycode-mapgen.py: Auto-generate the RFB keycode
set from the XT KBD set
* src/util/virkeycode.c: Add RFB keycode entry to table. Add a
verify check on cardinality of the codeOffset table
Audit all changes to the qemu vm->current_snapshot, and make them
update the saved xml file for both the previous and the new
snapshot, so that there is always at most one snapshot with
<active>1</active> in the xml, and that snapshot is used as the
current snapshot even across libvirtd restarts.
This patch does not fix the case of virDomainSnapshotDelete(,CHILDREN)
where one of the children is the current snapshot; that will be later.
* src/conf/domain_conf.h (_virDomainSnapshotDef): Alter member
type and name.
* src/conf/domain_conf.c (virDomainSnapshotDefParseString)
(virDomainSnapshotDefFormat): Update clients.
* docs/schemas/domainsnapshot.rng: Tighten rng.
* src/qemu/qemu_driver.c (qemuDomainSnapshotLoad): Reload current
snapshot.
(qemuDomainSnapshotCreateXML, qemuDomainRevertToSnapshot)
(qemuDomainSnapshotDiscard): Track current snapshot.
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.
https://bugzilla.redhat.com/show_bug.cgi?id=727709
mentions that if qemu fails to create the snapshot (such as what
happens on Fedora 15 qemu, which has qmp but where savevm is only
in hmp, and where libvirt is old enough to not try the hmp fallback),
then 'virsh snapshot-list dom' will show a garbage snapshot entry,
and the libvirt internal directory for storing snapshot metadata
will have a bogus file.
This fixes the fallout bug of polluting the snapshot-list with
garbage on failure (the root cause of the F15 bug of not having
fallback to hmp has already been fixed in newer libvirt releases).
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): Allocate
memory before making snapshot, and cleanup on failure. Don't
dereference NULL if transient domain exited during snapshot creation.
Our logic throws off analyzer tools:
ptr var = NULL;
if (flags == 0) flags = live ? _LIVE : _CONFIG;
if (flags & _LIVE) do stuff
if (flags & _CONFIG) var = non-null;
if (flags & _LIVE) do more stuff
else if (flags & _CONFIG) use var
the tools keep thinking that var can still be NULL in the last
if clause, adding the hint shuts them up.
* src/qemu/qemu_driver.c (qemuDomainSetBlkioParameters): Add a
static analysis hint.
Transient domains reject attempts to set autostart, and using
virDomainCreate to restart a domain only works on persistent
domains. Therefore, managed save makes no sense on transient
domains, and should be rejected up front rather than creating
an otherwise unrecoverable managed save file.
Besides, transient domains imply that a lot more management is
being done by the upper layer; this includes the assumption
that the upper layer is okay managing the saved state file
created by virDomainSave, and does not need to use managed save.
* src/libvirt.c: Document that transient domains are incompatible
with managed save.
* src/qemu/qemu_driver.c (qemuDomainManagedSave): Enforce it.
* src/libxl/libxl_driver.c (libxlDomainManagedSave): Likewise.
I noticed some inconsistent use of 'else'.
* src/qemu/qemu_driver.c (qemuCPUCompare)
(qemuDomainSnapshotCreateXML, qemuDomainRevertToSnapshot)
(qemuDomainSnapshotDiscard): Match coding conventions.
If a snapshot with the name already exists, virDomainSnapshotAssignDef()
just returns NULL, in which case the snapshot definition is leaked.
Currently this leak is not a big problem, since qemuDomainSnapshotLoad()
is only called once during initial startup of libvirtd.
Signed-off-by: Philipp Hahn <hahn@univention.de>
