Commit 7c6fc39 introduced a regression in the XML produced for older
clients. The argument at the time was that clients shouldn't be
depending on output-only data for something that is only going to
be triggered for a transient guest; but John Ferlan reported that
the automated testsuite was such a client. It's better to be safe
than sorry by guaranteeing back-compat cruft. Note that later
patches will be using <mirror> for active block commit, but there
we don't have to worry about back-compat.
* src/conf/domain_conf.c (virDomainDiskDefFormat): Restore old
style output when necessary.
* docs/schemas/domaincommon.rng: Validate back-compat style.
* docs/formatdomain.html.in: Update the documentation.
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-mirror-old.xml:
Update tests.
* tests/qemuxml2argvdata/qemuxml2argv-disk-mirror.xml: Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
Now that we track a disk mirror as a virStorageSource, we might
as well update the XML to theoretically allow any type of
mirroring destination (not just a local file). A later patch
will also be reusing <mirror> to track the block commit of the
top layer of a chain, which is another case where libvirt needs
to update the backing chain after the job is finally pivoted,
and since backing chains can have network backing files as the
destination to commit into, it makes more sense to display that
in the XML.
This patch changes output-only XML; it was already documented
that <mirror> does not affect a domain definition at this point
(because qemu doesn't provide persistent bitmaps yet). Any
application that was starting a block copy job with older libvirt
and then relying on the domain XML to determine if it was
complete will no longer be able to access the file= and format=
attributes of mirror that were previously used. However, this is
not going to be a problem in practice: the only time a block copy
job works is on a transient domain, and any app that is managing
a transient domain probably already does enough of its own
bookkeeping to know which file it is mirroring into without
having to re-read it from the libvirt XML. The one thing that
was likely to be used in a mirroring job was the ready=
attribute, which is unchanged. Meanwhile, I made sure the schema
and parser still accept the old format, even if we no longer
output it, so that upgrading from an older version of libvirt is
seamless.
* docs/schemas/domaincommon.rng (diskMirror): Alter definition.
* src/conf/domain_conf.c (virDomainDiskDefParseXML): Parse two
styles of mirror elements.
(virDomainDiskDefFormat): Output new style.
* tests/qemuxml2argvdata/qemuxml2argv-disk-mirror-old.xml: New
file, copied from...
* tests/qemuxml2argvdata/qemuxml2argv-disk-mirror.xml: ...here
before modernizing.
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-mirror-old*: New
files.
* tests/qemuxml2xmltest.c (mymain): Test both styles.
Signed-off-by: Eric Blake <eblake@redhat.com>
This patch implements formating and parsing code for the backing store
schema defined and documented by the previous patch.
This patch does not aim at providing full persistent storage of disk
backing chains yet. The formatter is supposed to provide the backing
chain detected when starting a domain and thus it is not formatted into
an inactive domain XML. The parser is implemented mainly for the purpose
of testing the XML generated by the formatter and thus it does not
distinguish between no backingStore element and an empty backingStore
element. This will have to change once we fully implement support for
user-supplied backing chains.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
<controller type='pci' index='0' model='pci-root'/>
is auto-added to pc* machine types.
Without this controller PCI bus 0 is not available and
no PCI addresses are assigned by default.
Since older libvirt supported PCI bus 0 even without
this controller, it is removed from the XML when migrating.
<vcpu> is not an optional node. The value for its 'placement'
actually always defaults to 'static' in the underlying codes.
(Even no 'cpuset' and 'placement' is specified, the domain
process will be pinned to all the available pCPUs).
In order to track a block copy job across libvirtd restarts, we
need to save internal XML that tracks the name of the file
holding the mirror. Displaying this name in dumpxml might also
be useful to the user, even if we don't yet have a way to (re-)
start a domain with mirroring enabled up front. This is done
with a new <mirror> sub-element to <disk>, as in:
<disk type='file' device='disk'>
<driver name='qemu' type='raw'/>
<source file='/var/lib/libvirt/images/original.img'/>
<mirror file='/var/lib/libvirt/images/copy.img' format='qcow2' ready='yes'/>
...
</disk>
For now, the element is output-only, in live domains; it is ignored
when defining a domain or hot-plugging a disk (since those contexts
use VIR_DOMAIN_XML_INACTIVE in parsing). The 'ready' attribute appears
when libvirt knows that the job has changed from the initial pulling
phase over to the mirroring phase, although absence of the attribute
is not a sure indicator of the current phase. If we come up with a way
to make qemu start with mirroring enabled, we can relax the xml
restriction, and allow <mirror> (but not attribute 'ready') on input.
Testing active-only XML meant tweaking the testsuite slightly, but it
was worth it.
* docs/schemas/domaincommon.rng (diskspec): Add diskMirror.
* docs/formatdomain.html.in (elementsDisks): Document it.
* src/conf/domain_conf.h (_virDomainDiskDef): New members.
* src/conf/domain_conf.c (virDomainDiskDefFree): Clean them.
(virDomainDiskDefParseXML): Parse them, but only internally.
(virDomainDiskDefFormat): Output them.
* tests/qemuxml2argvdata/qemuxml2argv-disk-mirror.xml: New test file.
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-mirror.xml: Likewise.
* tests/qemuxml2xmltest.c (testInfo): Alter members.
(testCompareXMLToXMLHelper): Allow more test control.
(mymain): Run new test.
