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Libvirt provides a portable, long term stable C API for managing the
virtualization technologies provided by many operating systems. It
includes support for QEMU, KVM, Xen, LXC, bhyve, Virtuozzo, VMware
vCenter and ESX, VMware Desktop, Hyper-V, VirtualBox and the POWER
Hypervisor.
3372f8fb5b
This patch reworks the Hyper-V driver structs and the code generator
to provide seamless support for both Hyper-V 2008 and 2012 or newer.
This does not implement any new libvirt APIs, it just adapts existing
2008-only driver to also handle 2012 and newer by sharing as much
driver code as possible (currently it's all of it :-)). This is needed
to set the foundation before we can move forward with implementing the
rest of the driver APIs.
With the 2012 release, Microsoft introduced "v2" version of Msvm_* WMI
classes. Those are largely the same as "v1" (used in 2008) but have some
new properties as well as need different wsman request URIs. To
accomodate those differences, most of work went into the code generator
so that it's "aware" of possibility of multiple versions of the same WMI
class and produce C code accordingly.
To accomplish this the following changes were made:
* the abstract hypervObject struct's data member was changed to a union
that has "common", "v1" and "v2" members. Those are structs that
represent WMI classes that we get back from wsman response. The
"common" struct has members that are present in both "v1" and "v2"
which the driver API callbacks can use to read the data from in
version-independent manner (if version-specific member needs to be
accessed the driver can check priv->wmiVersion and read from "v1" or
"v2" as needed). Those structs are guaranteed to be memory aligned
by the code generator (see the align_property_members implementation
that takes care of that)
* the generator produces *_WmiInfo for each WMI class "family" that
holds an array of hypervWmiClassInfoPtr each providing information
as to which request URI to use for each "version" of given WMI class
as well as XmlSerializerInfo struct needed to unserilize WS-MAN
responsed into the data structs. The driver uses those to make proper
WS-MAN request depending on which version it's connected to.
* the generator no longer produces "helper" functions such as
hypervGetMsvmComputerSystemList as those were originally just simple
wrappers around hypervEnumAndPull, instead those were hand-written
now (to keep driver changes minimal). The reason is that we'll have
more code coming implementing missing libvirt APIs and surely code
patterns will emerge that would warrant more useful "utility" functions
like that.
* a hypervInitConnection was added to the driver which "detects"
Hyper-V version by testing simple wsman request using v2 then falling
back to v1, obviously if both fail, the we're erroring out.
To express how the above translates in code:
void
hypervImplementSomeLibvirtApi(virConnectPtr conn, ...)
{
hypervPrivate *priv = conn->privateData;
virBuffer query = VIR_BUFFER_INITIALIZER;
hypervWqlQuery wqlQuery = HYPERV_WQL_QUERY_INITIALIZER;
Msvm_ComputerSystem *list = NULL; /* typed hypervObject instance */
/* the WmiInfo struct has the data needed for wsman request and
* response handling for both v1 and v2 */
wqlQuery.info = Msvm_ComputerSystem_WmiInfo;
wqlQuery.query = &query;
virBufferAddLit(&query, "select * from Msvm_ComputerSystem");
if (hypervEnumAndPull(priv, &wqlQuery, (hypervObject **) &list) < 0) {
goto cleanup;
}
if (list == NULL) {
/* none found */
goto cleanup;
}
/* works with v1 and v2 */
char *vmName = list->data.common->Name;
/* access property that is in v2 only */
if (priv->wmiVersion == HYPERV_WMI_VERSION_V2)
char *foo = list->data.v2->V2Property;
else
char *foo = list->data.v1->V1Property;
cleanup:
hypervFreeObject(priv, (hypervObject *)list);
}
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| .gnulib@94386a1366 | ||
| build-aux | ||
| daemon | ||
| docs | ||
| examples | ||
| gnulib | ||
| include/libvirt | ||
| m4 | ||
| po | ||
| src | ||
| tests | ||
| tools | ||
| .ctags | ||
| .dir-locals.el | ||
| .gitignore | ||
| .gitmodules | ||
| .mailmap | ||
| AUTHORS.in | ||
| autobuild.sh | ||
| autogen.sh | ||
| bootstrap | ||
| bootstrap.conf | ||
| cfg.mk | ||
| ChangeLog-old | ||
| config-post.h | ||
| configure.ac | ||
| COPYING | ||
| COPYING.LESSER | ||
| HACKING | ||
| libvirt-admin.pc.in | ||
| libvirt-lxc.pc.in | ||
| libvirt-qemu.pc.in | ||
| libvirt.pc.in | ||
| libvirt.spec.in | ||
| Makefile.am | ||
| Makefile.nonreentrant | ||
| mingw-libvirt.spec.in | ||
| README | ||
| README-hacking | ||
| run.in | ||
| TODO | ||
LibVirt : simple API for virtualization
Libvirt is a C toolkit to interact with the virtualization capabilities
of recent versions of Linux (and other OSes). It is free software
available under the GNU Lesser General Public License. Virtualization of
the Linux Operating System means the ability to run multiple instances of
Operating Systems concurrently on a single hardware system where the basic
resources are driven by a Linux instance. The library aim at providing
long term stable C API initially for the Xen paravirtualization but
should be able to integrate other virtualization mechanisms if needed.
Daniel Veillard <veillard@redhat.com>