Re: [libvirt] [PATCH v2 05/10] conf: alter disk mirror xml output

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(a)redhat.com&gt; --- docs/formatdomain.html.in | 20 +++++-- docs/schemas/domaincommon.rng | 29 ++++++--- src/conf/domain_conf.c | 69 ++++++++++++++++------ .../qemuxml2argv-disk-mirror-old.xml | 47 +++++++++++++++ .../qemuxml2argvdata/qemuxml2argv-disk-mirror.xml | 9 ++- .../qemuxml2xmlout-disk-mirror-old-inactive.xml | 41 +++++++++++++ .../qemuxml2xmlout-disk-mirror-old.xml | 52 ++++++++++++++++ tests/qemuxml2xmltest.c | 1 + 8 files changed, 235 insertions(+), 33 deletions(-) create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-mirror-old.xml create mode 100644 tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-mirror-old-inactive.xml create mode 100644 tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-mirror-old.xml