Taowei [Mon, 11 Aug 2014 10:06:06 +0000 (18:06 +0800)]
vbox: Rewrite vboxDomainSave
All vbox objects are child objects from the nsISupports in vbox's
C++ API version. Since the CAPI is generated from the C++ API, I
kept their relationship here, by the definitations below:
typedef struct nsISupports nsISupports;
typedef nsISupports IVirtualBox;
typedef nsISupports ISession;
and so on...
So, when calling the API from nsISupports, we don't need to do
typecasting, and things work still work well.
Laine Stump [Thu, 14 Aug 2014 16:34:23 +0000 (12:34 -0400)]
network: fix crash when starting a network with no <pf> element
Martin Kletzander pointed out in email that my commit 2a193f64
introduced a crash in networkCreateInterfacePool() during startup of
any network that doesn't have a <pf> subelement of its <forward>
element. He also supplied a patch.
Kiarie Kahurani [Mon, 11 Aug 2014 21:21:31 +0000 (00:21 +0300)]
src/xenxs: Refactor code formating CPU config
introduce functions
xenFormatXMCPUAllocation(virConfPtr conf, ......);
xenFormatXMCPUFeatures(virConfPtr conf, ......);
which formats CPU allocation and features config
Signed-off-by: Kiarie Kahurani <davidkiarie4@gmail.com> Signed-off-by: Jim Fehlig <jfehlig@suse.com>
Jianwei Hu [Wed, 13 Aug 2014 08:10:43 +0000 (16:10 +0800)]
Maximum vlanid should be 4095 in interface.rng
The correct vlanid range is 0~4095.
After merging this patch, we can not validate a interface xml with vlanid >= 4096.
[root@localhost ~]# cat vlan.xml
<interface type='vlan' name='eno1.4096'>
<start mode='onboot'/>
<protocol family='ipv4'>
<dhcp/>
</protocol>
<vlan tag='4096'>
<interface name='eno1'/>
</vlan>
</interface>
[root@localhost ~]# virt-xml-validate vlan.xml
vlan.xml:1: element interface: Relax-NG validity error : Invalid sequence in interleave
vlan.xml:6: element vlan: Relax-NG validity error : Element interface failed to validate content
vlan.xml:6: element vlan: Relax-NG validity error : Element vlan failed to validate attributes
vlan.xml fails to validate
[root@localhost ~]#
Here is a ip command help on this.
[root@localhost /]# ip link add link eno1 name eno1.90 type vlan help
Usage: ... vlan [ protocol VLANPROTO ] id VLANID [ FLAG-LIST ]
[ ingress-qos-map QOS-MAP ] [ egress-qos-map QOS-MAP ]
VLANPROTO: [ 802.1Q / 802.1ad ]
VLANID := 0-4095
FLAG-LIST := [ FLAG-LIST ] FLAG
FLAG := [ reorder_hdr { on | off } ] [ gvrp { on | off } ] [ mvrp { on | off } ]
[ loose_binding { on | off } ]
QOS-MAP := [ QOS-MAP ] QOS-MAPPING
QOS-MAPPING := FROM:TO
LXC: Fix virLXCControllerSetupDevPTS() wrt user namespaces
The gid value passed to devpts has to be translated by hand as
virLXCControllerSetupDevPTS() is called before setting up the user
and group mappings.
Otherwise devpts will use an unmapped gid and openpty()
will fail within containers.
Linux kernel commit 23adbe12
("fs,userns: Change inode_capable to capable_wrt_inode_uidgid")
uncovered that issue.
Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Ján Tomko <jtomko@redhat.com>
Jincheng Miao [Thu, 14 Aug 2014 03:37:45 +0000 (11:37 +0800)]
build: force configure failed when perl is missing
Perl is necessary to our build processing, it will invoke a lot of
generating script, like: gendispatch.pl. If perl is missing, it's
ok for build from git checkout, because autogen.sh will tell you.
But for compiling from a release tarball, configure will just record
a missing message, and continue, then build failed, like:
https://www.redhat.com/archives/libvirt-users/2014-August/msg00050.html
So need to enhance configure script to handle this negative case.
Reported-by: Hongbin Lu <hongbin@savinetwork.ca> Signed-off-by: Jincheng Miao <jmiao@redhat.com> Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Mo yuxiang [Thu, 14 Aug 2014 07:55:34 +0000 (15:55 +0800)]
conf: fix parsing 'cmd_per_lun' and 'max_sectors'
commit d9504941 introduces two new attributes "cmd_per_lun" and
"max_sectors" same with the names QEMU uses for virtio-scsi.
But the case of parsing them is not exact. Change to parse
them if controller has "driver" element.
This patch changes the setmaxmem function to support the '--live',
'--config', and '--current' flags by revectoring the code through
the setmem function using the VIR_DOMAIN_MEM_MAXIMUM flag. The
setmem code is refactored to handle both cases depending on the flag.
The changed maxmem code for the MEM_MAXIMUM path will not allow
modification to the memory values of an active guest unless the --config
switch is used.
Peter Krempa [Tue, 12 Aug 2014 14:10:39 +0000 (16:10 +0200)]
daemon: Limit default log level to journald to VIR_LOG_INFO
Libvirt is really chatty when the DEBUG log level is enabled. When a
host uses journald we'd enable debug logging to journald when only
specifying the debug log level. As journald may employ rate throttling
this would lock up the daemon until it's able to flush all debug
messages.
This patch changes the default log level to VIR_LOG_INFO when using the
default (unconfigured) log output to journald.
To still allow debug logging to journald the user now has to explicitly
specify journald as a log output with priority 1 in the "log_outputs"
configuration option. This patch also changes the config file template
to be explicit about this change and notify the user about the possible
consequence of debug logging into journald.
Michal Privoznik [Tue, 12 Aug 2014 15:39:52 +0000 (17:39 +0200)]
qemu_conf: Undefine the correct symbol
At the beginning of the qemu config file parsing function there
are 3 helper macros defined: GET_VALUE_BOOL, GET_VALUE_LONG and
GET_VALUE_STR. Later, when they are no longer needed they are
undefined in order to keep the namespace clean. However, the
GET_VALUE_STRING is undefined instead of GET_VALUE_STR.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
The 'actualpoolname' value is a name of the pool on the system,
such as shown by 'zpool list' command. Target makes no sense
here because volumes path is always /dev/zvol/$poolname/$volname.
User has to create a pool on his own, this driver doesn't
support pool creation currently.
A volume could be used with Qemu by adding an entry like this:
Peter Krempa [Tue, 12 Aug 2014 13:21:56 +0000 (15:21 +0200)]
qemu: migration: Check domain live state after exitting the monitor
In qemuMigrationToFile we enter the monitor multiple times and don't
check if the VM is still alive after returning form the monitor. Add the
checks to skip pieces of code in case the VM crashes while saving it's
state.
Peter Krempa [Tue, 12 Aug 2014 12:31:26 +0000 (14:31 +0200)]
qemu: managedsave: Check that VM is alive after entering async job
Saving a shutoff VM doesn't make sense and libvirtd crashes while
attempting to do that. Check that the domain is alive after entering
the save async job.
There's this <driver/> element under <interface/> which can have
several attributes. However, the driver element is currently formated
only if the driver's name or txmode has been specified. This makes
only a little sense as we parse even partial <driver/>, for instance:
Eric Blake [Mon, 11 Aug 2014 21:42:45 +0000 (15:42 -0600)]
docs: use correct hints per bus type in <disk> examples
Commit 4cf53158 tried to set up unique labels per disk in the
example, but ended up choosing strings that don't correspond
to the usual choice of bus types. Tweak the strings once again.
Laine Stump [Tue, 5 Aug 2014 21:15:31 +0000 (17:15 -0400)]
network: populate interface pool immediately when network is started
When a network is defined with "<pf dev='xyz'/>", libvirt will query
sysfs to learn the list of all virtual functions (VF) associated with
that Physical Function (PF) then populate the network's interface pool
accordingly. This action was previously done only when the first guest
actually requested an interface from the network. This patch changes
it to populate the pool immediately when the network is started. This
way any problems with the PF or its VFs will become apparent sooner.
Note that we can't remove the old calls to networkCreateInterfacePool
that happen whenever a guest requests an interface - doing so would be
asking for failures on hosts that had libvirt upgraded with a network
that had been started but not yet used.
This resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1047818
Laine Stump [Tue, 5 Aug 2014 20:40:52 +0000 (16:40 -0400)]
network: make networkCreateInterfacePool more robust
networkCreateInterfacePool was a bit loose in its error cleanup, which
could result in a network definition with interfaces in the pool that
were NULL. This would in turn lead to a libvirtd crash when a guest
tried to attach an interface using the network with that pool.
In particular this would happen when creating a pool to be used for
macvtap connections. macvtap needs the netdev name of the virtual
function in order to use it, and each VF only has a netdev name if it
is currently bound to a network driver. If one of the VFs of a PF
happened to be bound to the pci-stub or vfio-pci driver (indicating
it's already in use for PCI passthrough), or no driver at all, it
would have no name. In this case networkCreateInterfacePool would
return an error, but would leave the netdef->forward.nifs set to the
total number of VFs in the PF. The interface attach that triggered
calling of networkCreateInterfacePool (it uses a "lazy fill" strategy)
would simply fail, but the very next attempt to attach an interface
using the same network pool would result in a crash.
This patch refactors networkCreateInterfacePool to bring it more in
line with current coding practices (label name, use of a switch with
no default case) as well as providing the following two changes to
behavior:
1) If a VF with no netdev name is encountered, just log a warning and
continue; only fail if exactly 0 devices are found to put in the pool.
2) If the function fails, clean up any partial interface pool and set
netdef->forward.nifs to 0.
This resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1111455
This fixes compilation on kFreeBSD which otherwise fails like
CC util/libvirt_util_la-virprocess.lo
In file included from /usr/include/sys/cpuset.h:35:0,
from util/virprocess.c:43:
/usr/include/sys/_cpuset.h:49:43: error: 'NBBY' undeclared here (not in
a function)
long __bits[howmany(CPU_SETSIZE, _NCPUBITS)];
^
In file included from util/virprocess.c:43:0:
/usr/include/sys/cpuset.h:215:12: error: unknown type name 'cpusetid_t'
int cpuset(cpusetid_t *);
^
/usr/include/sys/cpuset.h:216:30: error: expected ')' before 'id_t'
int cpuset_setid(cpuwhich_t, id_t, cpusetid_t);
^
/usr/include/sys/cpuset.h:217:42: error: expected ')' before 'id_t'
int cpuset_getid(cpulevel_t, cpuwhich_t, id_t, cpusetid_t *);
^
/usr/include/sys/cpuset.h:218:48: error: expected ')' before 'id_t'
int cpuset_getaffinity(cpulevel_t, cpuwhich_t, id_t, size_t, cpuset_t
*);
^
/usr/include/sys/cpuset.h:219:48: error: expected ')' before 'id_t'
int cpuset_setaffinity(cpulevel_t, cpuwhich_t, id_t, size_t, const
cpuset_t *);
Tomoki Sekiyama [Fri, 8 Aug 2014 20:03:41 +0000 (16:03 -0400)]
qemu: use guest-fsfreeze-freeze-list command if mountpoints to freeze specified
A command to freeze a part of mounted file systems is implemented in
upstream QEMU-guest-agent with a name of 'guest-fsfreeze-freeze-list'.
This fixes the name of the command used to partial fsfreeze in qemu driver
when 'mountpoints' option is specified to virDomainFSFreeze API.
Jianwei Hu [Mon, 11 Aug 2014 06:41:33 +0000 (14:41 +0800)]
qemu: Actually clear bandwidth settings
The virDomainSetInterfaceParameters implementation in qemu over
VIR_DOMAIN_AFFECT_CONFIG doesn't work as expected. When trying to
clear out the bandwidth settings for an interface, it has no
actual effect:
John Ferlan [Thu, 24 Jul 2014 13:23:40 +0000 (09:23 -0400)]
qemu: Remove extraneous space in function prototypes
During review of the iSCSI hostdev series, eblake noted that the
prototypes shouldn't have the extranenous space between the "*" and
the function name:
John Ferlan [Wed, 9 Jul 2014 14:08:34 +0000 (10:08 -0400)]
hostdev: Add iSCSI hostdev XML
Introduce a new structure to handle an iSCSI host device based on the
existing virDomainHostdevSubsysSCSI by adding a "protocol='iscsi'" to
the <source/> element. The existing scsi_host subsystem RNG was modified
to read an optional "protocol='adapter'", although it won't be written
out nor is it documented as an option (by choice).
The new hostdev structure mimics the existing <disk/> element for an
iSCSI device (network) device. New XML is:
John Ferlan [Thu, 10 Jul 2014 13:11:30 +0000 (09:11 -0400)]
domain_conf: Common routine to handle network storage host xml def
In preparation for hostdev support for iSCSI and a virStorageNetHostDefPtr,
split out the network disk storage parsing of the 'host' element into a
separate routine.
Eric Blake [Wed, 6 Aug 2014 20:06:23 +0000 (14:06 -0600)]
blockjob: fix use-after-free in blockcopy
Commit febf84c2 tried to delay in-memory modification of the actual
domain disk structure until after the qemu event was received.
However, I missed that the code for block pivot had been temporarily
setting disk->src = disk->mirror prior to the qemu command, in order
to label the backing chain of a reused external blockcopy disk;
and calls into qemu while still in that state before finally undoing
things at the cleanup label. Since the qemu event handler then does:
virStorageSourceFree(disk->src);
disk->src = disk->mirror;
we have the sad race that a fast enough qemu event can cause a leak of
the original disk->src, as well as a use-after-free of the disk->mirror
contents, bad enough to crash libvirtd in some of my test runs, even
though the common case of the qemu event being much later won't trip
the race.
I'll go wear the brown paper bag of shame, for introducing a crasher
in between rc1 and rc2 of the freeze for 1.2.7 :( My only
consolation is that virDomainBlockJobAbort requires the domain:write
ACL, so it is not a CVE.
The valgrind report when the race occurs looks like:
==25612== Invalid read of size 4
==25612== at 0x50E7C90: virStorageSourceGetActualType (virstoragefile.c:1948)
==25612== by 0x209C0B18: qemuDomainDetermineDiskChain (qemu_domain.c:2473)
==25612== by 0x209D7F6A: qemuProcessHandleBlockJob (qemu_process.c:1087)
==25612== by 0x209F40C9: qemuMonitorEmitBlockJob (qemu_monitor.c:1357)
...
==25612== Address 0xe4b5610 is 0 bytes inside a block of size 200 free'd
==25612== at 0x4A07577: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==25612== by 0x50839E9: virFree (viralloc.c:582)
==25612== by 0x50E7E51: virStorageSourceFree (virstoragefile.c:2015)
==25612== by 0x209D7EFF: qemuProcessHandleBlockJob (qemu_process.c:1073)
==25612== by 0x209F40C9: qemuMonitorEmitBlockJob (qemu_monitor.c:1357)
* src/qemu/qemu_driver.c (qemuDomainBlockPivot): Don't corrupt
disk->src, and only label chain for blockcopy.
Eric Blake [Wed, 6 Aug 2014 20:48:59 +0000 (14:48 -0600)]
blockjob: avoid memory leak during block pivot
Valgrind caught a memory leak:
==2018== 9 bytes in 1 blocks are definitely lost in loss record 143 of 927
==2018== at 0x4A0645D: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==2018== by 0x8C42369: strdup (strdup.c:42)
==2018== by 0x50EACC9: virStrdup (virstring.c:676)
==2018== by 0x50E79E5: virStorageSourceCopy (virstoragefile.c:1845)
==2018== by 0x20A3FAA7: qemuDomainBlockCommit (qemu_driver.c:15620)
==2018== by 0x51DC6B2: virDomainBlockCommit (libvirt.c:20092)
I traced it to the fact that blockcopy and blockcommit end up
reparsing a backing chain on pivot, but the chain parsing code
doesn't gracefully handle the case where the backing file is
already known.
I'm not exactly sure when this was introduced, but suspect that the
refactoring in commit 9944b71 and friends that moved towards probing
in-place rather than into a temporary structure are part of the cause.
* src/util/virstoragefile.c (virStorageFileGetMetadataInternal):
Don't leak any prior value.
Laine Stump [Thu, 7 Aug 2014 14:50:21 +0000 (10:50 -0400)]
virsh: clean up attach-interface paragraph in man page
This makes the paragaph about attach-interface more descriptive and
correct, adding in a few bits of information that were previously
missing, e.g. --script is only allowed for bridge interfaces of Xen
domains, target name is regenerated if it starts with vnet, mac
address will be autogenerated if not specified.
(I did this in response to an email asking why a script couldn't be
specified for a bridge interface of a qemu domain, and why an
interface of type='ethernet' couldn't be created with
attach-interface)
Peter Krempa [Wed, 6 Aug 2014 13:17:00 +0000 (15:17 +0200)]
snapshot: conf: Enforce absolute paths on disk and memory images
RNG schema as well as the qemu driver requires absolute paths for memory
and disk snapshot image files but the XML parser was not enforcing it.
Add checks to avoid problems in qemu where the configuration it creates
is invalid.
Since commit be0782e1 we are parsing /proc/meminfo to find out the
default huge page size. However, if the host we are running at does
not support any huge pages (e.g. CONFIG_HUGETLB_PAGE is turned off),
we will not successfully parse the meminfo file and hence the whole
qemu driver init process fails. Moreover, the default huge page size
is needed if and only if there's at least one hugetlbfs mount point.
So the fix consists of moving the virFileGetDefaultHugepageSize
function call after the first hugetlbfs mount point is found.
With this fix, we fail to start with one or more hugetlbfs mounts and
malformed meminfo file, but that's expected (how can one mount
hugetlbfs without kernel supporting huge pages?). Workaround in that
case is to umount all the hugetlbfs mounts.
Reported-by: Jim Fehlig <jfehlig@suse.com> Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Prerna Saxena [Wed, 6 Aug 2014 10:20:11 +0000 (15:50 +0530)]
Node Devices: Fix nodedev-list for fc_host & vports.
In a system with Fiber Channel Host Adapters, a query to list all Fibre Channel
HBAs OR Vports currently returns empty list:
$ virsh nodedev-list --cap fc_host
$
Libvirt correctly discovers properties for all HBAs. However, the reporting
fails because of incorrect flag comparison while filtering these types.
This is fixed by removing references to 'VIR_CONNECT_LIST_NODE_DEVICES_CAP_*'
for comparison and replacing those with 'VIR_NODE_DEV_CAP_*'
Eric Blake [Tue, 5 Aug 2014 14:49:32 +0000 (08:49 -0600)]
blockjob: correctly report active commit for job info
Commit 232a31b munged job info to report 'active commit' instead of
'commit' when generating events, but forgot to also munge the polling
variant of the command.
* src/qemu/qemu_driver.c (qemuDomainBlockJobImpl): Adjust type as
needed.
Ján Tomko [Mon, 28 Jul 2014 12:46:46 +0000 (14:46 +0200)]
Don't overwrite errors from virNetDevBandwidthSet
Otherwise this beautiful error would be overwritten when
the function is called with a really high rate number:
2014-07-28 12:51:47.920+0000: 2304: error : virCommandWait:2399 :
internal error: Child process (/sbin/tc class add dev vnet0 parent 1:
classid 1:1 htb rate 4294968kbps) unexpected exit status 1: Illegal "rate"
Usage: ... qdisc add ... htb [default N] [r2q N]
default minor id of class to which unclassified packets are sent {0}
r2q DRR quantums are computed as rate in Bps/r2q {10}
debug string of 16 numbers each 0-3 {0}
... class add ... htb rate R1 [burst B1] [mpu B] [overhead O]
[prio P] [slot S] [pslot PS]
[ceil R2] [cburst B2] [mtu MTU] [quantum Q]
rate rate allocated to this class (class can still borrow)
burst max bytes burst which can be accumulated during idle period {computed}
mpu minimum packet size used in rate computations
overhead per-packet size overhead used in rate computations
linklay adapting to a linklayer e.g. atm
ceil definite upper class rate (no borrows) {rate}
cburst burst but for ceil {computed}
mtu max packet size we create rate map for {1600}
prio priority of leaf; lowe
Upon successful upload of a volume, the target volume and storage pool
were not updated to reflect any changes as a result of the upload. Make
use of the existing stream close callback mechanism to force a backend
pool refresh to occur in a separate thread once the stream closes. The
separate thread should avoid potential deadlocks if the refresh needed
to wait on some event from the event loop which is used to perform
the stream callback.
Currently, the function follows the usual pattern used in our code:
int ret = -1;
...
ret = 0;
cleanup:
return ret;
However, the function always call exit() on error, so the cleanup
label is never jumped onto. Therefore, it doesn't make any sense to
have the parse_argv function return an integer value, if it
effectively can return only value of zero.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Eric Blake [Sun, 3 Aug 2014 02:47:36 +0000 (20:47 -0600)]
build: fix build on cygwin
Cygwin has getifaddrs(), but not AF_LINK, leading to:
util/virstats.c: In function 'virNetInterfaceStats':
util/virstats.c:138:41: error: 'AF_LINK' undeclared (first use in this function)
if (ifa->ifa_addr->sa_family != AF_LINK)
...
* src/util/virstats.c (virNetInterfaceStats): Only use getifaddrs
if AF_LINK is present.
Laine Stump [Fri, 1 Aug 2014 21:51:37 +0000 (17:51 -0400)]
network: always set disable_ipv6, even when it should be 0
libvirt previously only touched an interface's disable_ipv6 setting in
sysfs if it needed to be set to 1, assuming that 0 is the
default. Apparently that isn't always the case though (kernel 3.15.7-1
in Arch Linux reportedly defaults a new interface's disable_ipv6
setting to 1) so this patch explicitly sets it to 0 or 1 as
appropriate.
and watch qemu shorten the backing chain by one, followed by
libvirt automatically updating the dumpxml output, effectively
undoing the work of virsh snapshot-commit --no-metadata --disk-only.
Commit is SOOOO much faster than blockpull, when I'm still fairly
close in time to when the temporary qcow2 wrapper file was created
via a snapshot operation!
* src/qemu/qemu_driver.c (qemuDomainBlockCommit): Implement live
commit.
Eric Blake [Tue, 29 Jul 2014 03:46:44 +0000 (21:46 -0600)]
blockcommit: track job type in xml
A future patch is going to wire up qemu active block commit jobs;
but as they have similar events and are canceled/pivoted in the
same way as block copy jobs, it is easiest to track all bookkeeping
for the commit job by reusing the <mirror> element. This patch
adds domain XML to track which job was responsible for creating a
mirroring situation, and adds a job='copy' attribute to all
existing uses of <mirror>. Along the way, it also massages the
qemu monitor backend to read the new field in order to generate
the correct type of libvirt job (even though it requires a
future patch to actually cause a qemu event that can be reported
as an active commit). It also prepares to update persistent XML
to match changes made to live XML when a copy completes.
* docs/schemas/domaincommon.rng: Enhance schema.
* docs/formatdomain.html.in: Document it.
* src/conf/domain_conf.h (_virDomainDiskDef): Add a field.
* src/conf/domain_conf.c (virDomainBlockJobType): String conversion.
(virDomainDiskDefParseXML): Parse job type.
(virDomainDiskDefFormat): Output job type.
* src/qemu/qemu_process.c (qemuProcessHandleBlockJob): Distinguish
active from regular commit.
* src/qemu/qemu_driver.c (qemuDomainBlockCopy): Set job type.
(qemuDomainBlockPivot, qemuDomainBlockJobImpl): Clean up job type
on completion.
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-mirror-old.xml:
Update tests.
* tests/qemuxml2argvdata/qemuxml2argv-disk-mirror.xml: Likewise.
* tests/qemuxml2argvdata/qemuxml2argv-disk-active-commit.xml: New
file.
* tests/qemuxml2xmltest.c (mymain): Drive new test.
Domain config: write <features/> if some capabilities are set.
If all features are set to default (including the capabilities policy),
but some capabilities are toggled, we need to output the <features>
element when formatting the config.
Eric Blake [Tue, 29 Jul 2014 20:42:45 +0000 (14:42 -0600)]
blockjob: properly track blockcopy xml changes on disk
We were not directly saving the domain XML to file after starting
or finishing a blockcopy. Without the startup write, a libvirtd
restart in the middle of a copy job would forget that the job was
underway. Then at pivot, we were indirectly writing new XML in
reaction to events that occur as we stop and restart the guest CPUs.
But there was a race: since pivot is an async action, it is possible
that libvirtd is restarted before the pivot completes, so if XML
changes during the event, that change was not written. The original
blockcopy code cleared out the <mirror> element prior to restarting
the CPUs, but this is also a race, observed if a user does an async
pivot and a dumpxml before the event occurs. Furthermore, this race
will interfere with active commit in a future patch, because that
code will rely on the <mirror> element at the time of the qemu event
to determine whether to inform the user of a normal commit or an
active commit.
Fix things by saving state any time we modify live XML, while
delaying XML disk modifications until after the event completes. We
still need a to teach libvirtd restarts to examine all existing
<mirror> elements to see if the job completed in the meantime (that
is, if libvirtd misses the event, the updated state still needs to be
updated in live XML), but that will be a later patch, in part because
we also need to to start taking advantage of newer qemu's ability to
keep the job around after completion rather than the current usage
where the job disappears both on error and on success.
* src/qemu/qemu_driver.c (qemuDomainBlockCopy): Track XML change
on disk.
(qemuDomainBlockJobImpl, qemuDomainBlockPivot): Move job-end XML
rewrites...
* src/qemu/qemu_process.c (qemuProcessHandleBlockJob): ...here.