If a domain has inactive XML we want to transfer it to destination
when migrating with VIR_MIGRATE_PERSIST_DEST. In order to harm
the migration protocol as least as possible, a optional cookie was
chosen.
The previous patch removed all snapshots, but not the directory
where the snapshots lived, which is still a form of stale data.
* src/qemu/qemu_domain.c (qemuDomainRemoveInactive): Wipe any
snapshot directory.
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.
Detected by Coverity. The only way to get to error_unlink is if
path was successfully assigned, so the if was useless. Meanwhile,
there was a return statement that did not free path.
* src/locking/lock_driver_sanlock.c
(virLockManagerSanlockSetupLockspace): Fix mem-leak, and drop
useless if.
Related #BZ: https://bugzilla.redhat.com/show_bug.cgi?id=702260.
There are two problems described in the BZ:
1) "Can't remove open logical volume".
2) "Unable to deactivate logical volume "foo""
This patch just intends to fix 2), as 1) is expected if the vol
is still used by something, and you never known if "lvchange -an"
will fail or not either (sometime, it will succeed, sometimes not).
We'd better not look for trouble, :-)
For 2), that's caused by race between lvremove and udev event handling,
the only workable way now is to wait the events handling are finished,
though it might introduce latencies, as "udevadmin settle" exits
after *all* events are handled, it's the only way we can fix
the racing in libvirt layer.
See https://bugzilla.redhat.com/show_bug.cgi?id=570359 for more
details.
* src/qemu/qemu_process.c: Taking if (qemuDomainObjEndJob(driver, obj) == 0)
true branch then 'obj' is NULL, virDomainObjIsActive(obj) and
virDomainObjUnref(obj) will dereference NULL pointer.
Signed-off-by: Alex Jia <ajia@redhat.com>
Once virDomainReboot is called for a domain, guest OS initiated shutdown
would always result in reboot instead of shutdown. Only
virDomainShutdown would actually shutd such domain down. That's because
we forgot to reset fakeReboot flag once we asked the domain to reboot.
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".
The next patch will add a syntax check that flags this usage in xen
as awkward - while it was valid memory management, it was very hard
to maintain. Swapping to a more traditional allocation may be a bit
slower, but easier to understand.
* src/xen/xend_internal.c (xenDaemonListDomainsOld): Use two-level
allocation, rather than abusing allocation function.
(xenDaemonLookupByUUID): Update caller.
gcc warns when building libvirt 0.9.5 on a 32-bit machine:
qemu/qemu_migration.c: In function 'qemuMigrationToFile':
qemu/qemu_migration.c:2727:38: error: large integer implicitly truncated to unsigned type [-Woverflow]
* src/qemu/qemu_domain.h (QEMU_DOMAIN_FILE_MIG_BANDWIDTH_MAX): Cap
to long when building for 32-bit platform.
Inexplicably the sanlock code all got placed under the GPLv2-only,
so libvirt's use of sanlock introduces a license incompatibility.
The sanlock developers have now rearranged the code such that there
is a 'sanlock_client.so' which is LGPLv2+ while their daemon remains
GPLv2-only. To use the new client library we need to call the new
sanlock_init and sanlock_align APIs instead of sanlock_direct_init
and sanlock_direct_align. These APIs calls are now routed via the
sanlock daemon, instead of doing direct I/O calls to disk.
For all this we require sanlock >= 1.8
* configure.ac: Check for sanlock_client.so instead of sanlock.so
and fix various comments
* libvirt.spec.in: Mandate sanlock >= 1.8
* src/Makefile.am: Link to -lsanlock_client
* src/locking/lock_driver_sanlock.c: Use sanlock_init and
sanlock_align
Libvirt loads the domain conf from status XML if it's running when
starting up. The problem is there is no record of the original conf.
(dom->newDef is NULL here).
So libvirt won't be able to restore the domain conf to original one
when destroying/shutdown. E.g.
1) attach a device without "--persistent"
2) restart libvirtd
3) destroy domain
4) start domain
One will see the the disk still exists.
This patch is to fix the peoblem by assigning persistent domain conf
to dom->newDef if it's NULL and the domain is running.
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.
* src/vmx/vmx.c: fix memory leak, 'def' has a initial value 'NULL', so
'goto cleanup' is perfected instead of adding a virConfFree before
'return NULL'.
Signed-off-by: Alex Jia <ajia@redhat.com>
Leak present since introduction of remoteDomainBuildEventGraphics
in commit 987e31e.
* src/remote/remote_driver.c: fix memory leak.
Signed-off-by: Alex Jia <ajia@redhat.com>
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.
When libvirt calls virInitialize it creates a thread local
for the virErrorPtr storage, and registers a callback to
cleanup memory when a thread exits. When libvirt is dlclose()d
or otherwise made non-resident, the callback function is
removed from memory, but the thread local may still exist
and if a thread later exists, it will invoke the callback
and SEGV. There may also be other thread locals with callbacks
pointing to libvirt code, so it is in general never safe to
unload libvirt.so from memory once initialized.
To allow dlclose() to succeed, but keep libvirt.so resident
in memory, link with '-z nodelete'. This issue was first
found with the libvirt CIM provider, but can potentially
hit many of the dynamic language bindings which all ultimately
involve dlopen() in some way, either on libvirt.so itself,
or on the glue code for the binding which in turns links
to libvirt
* configure.ac, src/Makefile.am: Ensure libvirt.so is linked
with -z nodelete
* cfg.mk, .gitignore, tests/Makefile.am, tests/shunloadhelper.c,
tests/shunloadtest.c: A test case to unload libvirt while
a thread is still running.
Qemu sends STOP event as part of the shutdown process. Detect such STOP
event and consider shutdown to be reason of emitting such event. That's
the best we can do until qemu provides us the reason directly in STOP
event. This allows us to report shutdown reason for paused state so that
apps can detect domains that failed to finish the shutdown process
(e.g., because qemu is buggy and doesn't exit on SIGTERM or it is
blocked in flushing disk buffers).
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.
When a domain is rebooted using libvirt API, we use fake reboot
consisting of shutting down and resetting the domain. Thus we see a
SHUTDOWN event and set gotShutdown flag. But we never reset it back and
if the domain crashes after it was rebooted this way, we consider it was
a normal shutdown and not a crash.
Commit 4454a9efc7 changed shutoff reason
from VIR_DOMAIN_SHUTOFF_CRASHED to VIR_DOMAIN_SHUTOFF_FAILED in case we
see an unexpected EOF on monitor connection. But FAILED reason is
dedicated for domains that fail to start. CRASHED reason is the right
one to use in this situation.
Libvirt special-cases a specific VIR_ERR_RPC from the remote driver
back into VIR_ERR_NO_SUPPORT on the client, so that clients can
handle missing rpc functions the same whether the hypervisor driver
is local or remote. However, commit c1b22644 introduced a regression:
VIR_FROM_THIS changed from VIR_FROM_REMOTE to VIR_FROM_RPC, so the
special casing no longer works if the server uses the newer error
domain.
* src/rpc/virnetclientprogram.c
(virNetClientProgramDispatchError): Also cater to 0.9.3 and newer.
This patch fixes the bug shown in bugzilla 738778. It's not an nwfilter problem but a connection sharing / closure issue.
https://bugzilla.redhat.com/show_bug.cgi?id=738778
Depending on the speed / #CPUs of the machine you are using you may not see this bug all the time.
* conf/domain_conf.c: allocate memory to def->redirdevs in
virDomainDefParseXML such as VIR_ALLOC_N(def->redirdevs, n),
however, virDomainDefFree(def) hasn't released these memory.
* Detected in valgrind run:
==19820== 209 (16 direct, 193 indirect) bytes in 1 blocks are definitely lost in loss record 25 of 26
==19820== at 0x4A04A28: calloc (vg_replace_malloc.c:467)
==19820== by 0x4A13AF: virAllocN (memory.c:129)
==19820== by 0x4D4A0E: virDomainDefParseXML (domain_conf.c:7258)
==19820== by 0x4D4C93: virDomainDefParseNode (domain_conf.c:7512)
==19820== by 0x4D562F: virDomainDefParse (domain_conf.c:7465)
==19820== by 0x415863: testCompareXMLToXMLFiles (qemuxml2xmltest.c:35)
==19820== by 0x415982: testCompareXMLToXMLHelper (qemuxml2xmltest.c:80)
==19820== by 0x416D31: virtTestRun (testutils.c:140)
==19820== by 0x415604: mymain (qemuxml2xmltest.c:192)
==19820== by 0x416437: virtTestMain (testutils.c:689)
==19820== by 0x3CA7A1ECDC: (below main) (in /lib64/libc-2.12.so)
==19820==
==19820== LEAK SUMMARY:
==19820== definitely lost: 16 bytes in 1 blocks
==19820== indirectly lost: 193 bytes in 5 blocks
==19820== possibly lost: 0 bytes in 0 blocks
==19820== still reachable: 1,054 bytes in 21 blocks
* How to reproduce?
% valgrind -v --leak-check=full ./tests/qemuxml2xmltest
Signed-off-by: Alex Jia <ajia@redhat.com>
Mac OS X 10.6. Snow Leopard and probably other do not provide a mkfs
command to create filesystems. Macro MKFS then remained undefined and
did not provide any substitute, so that build failed on a missing
argument.
Struct virStoragePoolProbeResult was compiled in conditionaly, but
virStorageBackendFileSystemProbe used it unconditionaly. This patch
exempts the struct from conditional include.
Documentation did not specify, that some permissions are required on
target path for coredump for the user running the hypervisor.
Diff to v1:
- reword statements
The new doc text had a few readability issues. Also, the
monitor command text copied a bit too much from the attach case.
* src/libvirt-qemu.c (virDomainQemuMonitorCommand)
(virDomainQemuAttach): Fix typos and grammar.
Adjust qemuMigrationRun() to use migMaxBandwidth in qemuDomainObjPrivate
structure when setting qemu migration speed. Caller-specified 'resource'
parameter overrides migMaxBandwidth.
The qemu migration speed default is 32MiB/s as defined in migration.c
/* Migration speed throttling */
static int64_t max_throttle = (32 << 20);
There's no need to throttle migration when targeting a file, so set migration
speed to unlimited prior to migration, and restore to libvirt default value
after migration.
Default units is MB for migrate_set_speed monitor command, so
(INT64_MAX / (1024 * 1024)) is used for unlimited migration speed.
Tested with both json and text monitors.
Now that migration speed is stored in qemuDomainObjPrivate structure,
save the new value when invoking qemuDomainMigrateSetMaxSpeed().
Allow setting migration speed on inactive domain too.
The maximum bandwidth that can be consumed when migrating a domain
is better classified as an operational vs configuration parameter of
the dommain. As such, store this parameter in qemuDomainObjPrivate
structure.
Commit c246b025 added new functions, but forgot to export them,
resulting in a build failure when using modules.
* src/libvirt_private.syms (network.h): Export new functions.
Commit 973fcd8f introduced the ability for qemu to reject snapshot
reversion on an ABI incompatibility; but the very example that was
first proposed on-list[1] as a demonstration of an ABI incompatibility,
namely that of changing the max memory allocation, was not being
checked for, resulting in a cryptic failure when running with larger
max mem than what the snapshot was created with:
error: operation failed: Error -22 while loading VM state
This commit merely protects the three variables within mem that are
referenced by qemu_command.c, rather than all 7 (the other 4 variables
affect cgroup handling, but as far as I can tell, have no visible effect
to the qemu guest). This also affects migration and save file handling,
which are other places where we perform ABI compatibility checks.
[1] https://www.redhat.com/archives/libvir-list/2010-December/msg00331.html
* src/conf/domain_conf.c (virDomainDefCheckABIStability): Add
memory sizing checks.
Commit 498d783 cleans up some of virtual file names for parsing strings
in memory. This patch cleans up (hopefuly) the rest forgotten by the
first patch.
This patch also changes all of the previously modified "filenames" to
valid URI's replacing spaces for underscores.
Changes to v1:
- Replace all spaces for underscores, so that the strings form valid
URI's
- Replace spaces in places changed by commit 498d783
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>
'+' in strings get translated to ' ' when editing domains.
While xenDaemonDomainCreateXML() did URL-escape the sexpr,
xenDaemonDomainDefineXML() did not.
Remove the explicit urlencode() in xenDaemonDomainCreateXML() and add
the direct encoding calls to xend_op_ext() because it calls xend_post()
which uses "Content-Type: application/x-www-form-urlencoded". According
to <http://www.w3.org/TR/html4/interact/forms.html#h-17.13.4.1> this
requires all parameters to be url-encoded as specified in rfc1738.
Notice: virBufferAsprintf(..., "%s=%s", ...) is again replaced by three
calls to virBufferURIEncodeString() and virBufferAddChar() because '='
is a "reserved" character, which would get escaped by
virBufferURIEncodeString(), which - by the way - escapes anything not
c_isalnum().
Signed-off-by: Philipp Hahn <hahn@univention.de>
While parsing XML strings from memory, the previous convention in
libvirt was to set the virtual file name to "domain.xml" or something
similar. This could potentialy trick the user into looking for a file
named domain.xml on the disk in an attempt to fix the error.
This patch changes these filenames to something that can't be as easily
confused for a valid filename.
Examples of error messages:
---------------------------
Error while loading file from disk:
15:07:59.015: 527: error : catchXMLError:709 : /path/to/domain.xml:1: StartTag: invalid element name
<domain type='kvm'><
--------------------^
Error while parsing definition in memory:
15:08:43.581: 525: error : catchXMLError:709 : (domain definition):2: error parsing attribute name
<name>vm1</name>
--^
Regression introduced in commit d6f6b2d194. Running
'virsh snapshot-create dom' would mistakenly report that
disks can only be specified for disk snapshots.
* src/conf/domain_conf.c (virDomainSnapshotDefParseString): Only
give error about no disk support when <disk> was found.
These functions access internals of the opaque object, and do
not need any rpc counterpart. It could be argued that we should
have provided these when snapshot objects were first introduced,
since all the other vir*Ptr objects have at least a GetName accessor.
* include/libvirt/libvirt.h.in (virDomainSnapshotGetName)
(virDomainSnapshotGetDomain, virDomainSnapshotGetConnect): Declare.
* src/libvirt.c (virDomainSnapshotGetName)
(virDomainSnapshotGetDomain, virDomainSnapshotGetConnect): New
functions.
* src/libvirt_public.syms: Export them.
Xen PV domU's have no PCI bus. node_device_udev.c calls pci_system_init
which looks for /sys/bus/pci. If it does not find /sys/bus/pci (which it
won't in a Xen PV domU) it returns unsuccesfully (ENOENT), which libvirt
considers fatal. This makes libvirt unusable in this environment, even
though there are plenty of valid virtualisation options that work
there (LXC, UML, and QEmu spring to mind)
https://bugzilla.redhat.com/show_bug.cgi?id=709471
Signed-off-by: Soren Hansen <soren@linux2go.dk>
* src/rpc/virnettlscontext.c: fix memory leak on
virNetTLSContextValidCertificate.
* Detected in valgrind run:
==25667==
==25667== 6,085 (44 direct, 6,041 indirect) bytes in 1 blocks are definitely
lost in loss record 326 of 351
==25667== at 0x4005447: calloc (vg_replace_malloc.c:467)
==25667== by 0x4F2791F3: _asn1_add_node_only (structure.c:53)
==25667== by 0x4F27997A: _asn1_copy_structure3 (structure.c:421)
==25667== by 0x4F276A50: _asn1_append_sequence_set (element.c:144)
==25667== by 0x4F2743FF: asn1_der_decoding (decoding.c:1194)
==25667== by 0x4F22B9CC: gnutls_x509_crt_import (x509.c:229)
==25667== by 0x805274B: virNetTLSContextCheckCertificate
(virnettlscontext.c:1009)
==25667== by 0x804DE32: testTLSSessionInit (virnettlscontexttest.c:693)
==25667== by 0x804F14D: virtTestRun (testutils.c:140)
==25667==
==25667== 23,188 (88 direct, 23,100 indirect) bytes in 11 blocks are definitely
lost in loss record 346 of 351
==25667== at 0x4005447: calloc (vg_replace_malloc.c:467)
==25667== by 0x4F22B841: gnutls_x509_crt_init (x509.c:50)
==25667== by 0x805272B: virNetTLSContextCheckCertificate
(virnettlscontext.c:1003)
==25667== by 0x804DDD1: testTLSSessionInit (virnettlscontexttest.c:673)
==25667== by 0x804F14D: virtTestRun (testutils.c:140)
* How to reproduce?
% cd libvirt && ./configure && make && make -C tests valgrind
or
% valgrind -v --leak-check=full ./tests/virnettlscontexttest
Signed-off-by: Alex Jia <ajia@redhat.com>
Variable 'l_disk' initialized to a null pointer value, control jumps to 'case
VIR_DOMAIN_DISK_DEVICE_DISK and then taking false branch, Within the expansion
of the macro 'libxlError': Field access results in a dereference of a null
pointer (loaded from variable 'l_disk').
* src/libxl/libxl_driver.c: Field access results in a dereference of a null
pointer (loaded from variable 'l_disk')
Signed-off-by: Alex Jia <ajia@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.
Although we were initializing worker threads during pool creating,
we missed this during virThreadPoolSendJob. This bug led to segmenation
fault as worker thread free() given argument.
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.
This patch adds handlers for modification of guest's interface
link state. Both HMP and QMP commands are supported, but as the
link state functionality is from the beginning supported in QMP
the HMP code will probably never be used.
A new element is introduced to XML that allows to control
state of virtual network interfaces in hypervisors.
Live modification of the link state allows networking tools
propagate topology changes to guest OS or testing of
scenarios in complex (virtual) networks.
This patch adds elements to XML grammars and parsing and generating
code.
This patch adds functions to compare structures containing network
device configuration for equality. They serve for the purpose of
disallowing unsupported changes to live network devices.
This patch modifies error handling function for the XML parser provided
by libxml2.
Originaly only a line number and error message were logged. With this
new error handler function, the user is provided with a more complex
description of the parsing error.
Context of the error is printed in libXML2 style and filename of the
file, that caused the error is printed. Example of an parse error:
13:41:36.262: 16032: error : catchXMLError:706 :
/etc/libvirt/qemu/rh_bad.xml:58: Opening and ending tag mismatch: name
line 2 and domain
</domain>
---------^
Context of the error gives the user hints that may help to quickly
locate a corrupt xml file.
fixes BZs:
----------
Bug 708735 - [RFE] Show column and line on XML parsing error
https://bugzilla.redhat.com/show_bug.cgi?id=708735
Bug 726771 - libvirt does not specify problem file if persistent xml is
invalid
https://bugzilla.redhat.com/show_bug.cgi?id=726771
It is important to be able to attach USB redirected devices to a
particular controller (one that supports USB2 for instance).
Without this patch, only the default bus was used.
<redirdev bus='usb' type='spicevmc'>
<address type='usb' bus='0' port='4'/>
</redirdev>
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 creates an optional BeginJob queue size limit. When
active, all other attempts above level will fail. To set this
feature assign desired value to max_queued variable in qemu.conf.
Setting it to 0 turns it off.
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.
No one uses this yet, but it will be important once
virDomainSnapshotCreateXML learns a VIR_DOMAIN_SNAPSHOT_DISK_ONLY
flag, and the xml allows passing in the new file names.
* src/qemu/qemu_monitor.h (qemuMonitorDiskSnapshot): New prototype.
* src/qemu/qemu_monitor_text.h (qemuMonitorTextDiskSnapshot):
Likewise.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONDiskSnapshot):
Likewise.
* src/qemu/qemu_monitor.c (qemuMonitorDiskSnapshot): New
function.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONDiskSnapshot):
Likewise.
Snapshots alter the set of disk image files opened by qemu, so
they must be audited. But they don't involve a full disk definition
structure, just the new filename. Make the next patch easier by
refactoring the audit routines to just operate on file name.
* src/conf/domain_audit.h (virDomainAuditDisk): Update prototype.
* src/conf/domain_audit.c (virDomainAuditDisk): Act on strings,
not definition structures.
(virDomainAuditStart): Update caller.
* src/qemu/qemu_hotplug.c (qemuDomainChangeEjectableMedia)
(qemuDomainAttachPciDiskDevice, qemuDomainAttachSCSIDisk)
(qemuDomainAttachUsbMassstorageDevice)
(qemuDomainDetachPciDiskDevice, qemuDomainDetachDiskDevice):
Likewise.
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.
Adds an optional element to <domainsnapshot>, which will be used
to give user control over external snapshot filenames on input,
and specify generated filenames on output.
For now, no driver accepts this element; that will come later.
<domainsnapshot>
...
<disks>
<disk name='vda' snapshot='no'/>
<disk name='vdb' snapshot='internal'/>
<disk name='vdc' snapshot='external'>
<driver type='qcow2'/>
<source file='/path/to/new'/>
</disk>
</disks>
<domain>
...
<devices>
<disk ...>
<driver name='qemu' type='raw'/>
<target dev='vdc'/>
<source file='/path/to/old'/>
</disk>
</devices>
</domain>
</domainsnapshot>
* src/conf/domain_conf.h (_virDomainSnapshotDiskDef): New type.
(_virDomainSnapshotDef): Add new elements.
(virDomainSnapshotAlignDisks): New prototype.
* src/conf/domain_conf.c (virDomainSnapshotDiskDefClear)
(virDomainSnapshotDiskDefParseXML, disksorter)
(virDomainSnapshotAlignDisks): New functions.
(virDomainSnapshotDefParseString): Parse new fields.
(virDomainSnapshotDefFree): Clean them up.
(virDomainSnapshotDefFormat): Output them.
* src/libvirt_private.syms (domain_conf.h): Export new function.
* docs/schemas/domainsnapshot.rng (domainsnapshot, disksnapshot):
Add more xml.
* docs/formatsnapshot.html.in: Document it.
* tests/domainsnapshotxml2xmlin/disk_snapshot.xml: New test.
* tests/domainsnapshotxml2xmlout/disk_snapshot.xml: Update.
In order to distinguish disk snapshots from system checkpoints, a
new state value that is only valid for snapshots is helpful.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_LAST): New placeholder.
* src/conf/domain_conf.h (virDomainSnapshotState): New enum mapping.
(VIR_DOMAIN_DISK_SNAPSHOT): New internal enum value.
* src/conf/domain_conf.c (virDomainState): Use placeholder.
(virDomainSnapshotState): Extend mapping by one for use in snapshot.
(virDomainSnapshotDefParseString, virDomainSnapshotDefFormat):
Handle new state.
(virDomainObjSetState, virDomainStateReasonToString)
(virDomainStateReasonFromString): Avoid compiler warnings.
* tools/virsh.c (vshDomainState, vshDomainStateReasonToString):
Likewise.
* src/libvirt_private.syms (domain_conf.h): Export new functions.
* docs/schemas/domainsnapshot.rng: Tighten state definition.
* docs/formatsnapshot.html.in: Document it.
* tests/domainsnapshotxml2xmlout/disk_snapshot.xml: New 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.
The previous patch introduced new config, but if a hypervisor does
not support that new config, someone can write XML that does not
behave as documented. This prevents some of those cases by
explicitly rejecting transient disks for several hypervisors.
Disk snapshots will require a new flag to actually affect a snapshot
creation, so there's not much to reject there.
* src/qemu/qemu_command.c (qemuBuildDriveStr): Reject transient
disks for now.
* src/libxl/libxl_conf.c (libxlMakeDisk): Likewise.
* src/xenxs/xen_sxpr.c (xenFormatSxprDisk): Likewise.
* src/xenxs/xen_xm.c (xenFormatXMDisk): Likewise.
As discussed here:
https://www.redhat.com/archives/libvir-list/2011-August/msg00361.htmlhttps://www.redhat.com/archives/libvir-list/2011-August/msg00552.html
Adds snapshot attribute and transient sub-element:
<devices>
<disk type=... snapshot='no|internal|external'>
...
<transient/>
</disk>
</devices>
* docs/schemas/domaincommon.rng (snapshot): New define.
(disk): Add snapshot and persistent attributes.
* docs/formatdomain.html.in: Document them.
* src/conf/domain_conf.h (virDomainDiskSnapshot): New enum.
(_virDomainDiskDef): New fields.
* tests/qemuxml2argvdata/qemuxml2argv-disk-transient.xml: New
test of rng, no args counterpart until qemu support is complete.
* tests/qemuxml2argvdata/qemuxml2argv-disk-snapshot.args: New
file, snapshot attribute does not affect args.
* tests/qemuxml2argvdata/qemuxml2argv-disk-snapshot.xml: Likewise.
* tests/qemuxml2argvtest.c (mymain): Run new test.
Fix bug #611823 storage driver should prohibit pools with duplicate
underlying storage.
Add internal API virStoragePoolSourceFindDuplicate() to do uniqueness
check based on source location infomation for pool type.
* AUTHORS: add Lei Li
At least Xen-3.4.3 translates the /vm/localtime SXPR value to
/domain/platform/localtime and /domain/image/{linux,hvm}/localtime when
the domain is defined. When reading back that information libvirt only
handles HVM domains, but not PV domains: This results in libvirtd always
returning
<clock offset="utc"/>
while Xend used (localtime 1).
For PV domains use /domain/image/linux/localtime.
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.
Commit 69278878 fixed one direction of arbitrarily-named snapshots,
but not the round trip path. While auditing domain_conf, I found
a couple other instances that weren't escaping arbitrary strings.
* src/conf/domain_conf.c (virDomainFSDefFormat)
(virDomainGraphicsListenDefFormat, virDomainSnapshotDefFormat):
Escape arbitrary strings.
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.
Minor semantic change - allow domain xml to be generated in place
within a larger buffer, rather than having to go through a
temporary string.
* src/conf/domain_conf.c (virDomainDefFormatInternal): Add
parameter.
(virDomainDefFormat, virDomainObjFormat): Update callers.
