1
0
mirror of https://gitlab.com/libvirt/libvirt.git synced 2024-12-22 17:34:18 +03:00

docs: Convert 'formatcaps' page to rst

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
This commit is contained in:
Peter Krempa 2022-04-08 10:25:27 +02:00
parent f01f957792
commit 8b3d9314ae
3 changed files with 198 additions and 223 deletions

View File

@ -1,222 +0,0 @@
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<body>
<h1>Driver capabilities XML format</h1>
<ul id="toc"></ul>
<h2><a id="elements">Element and attribute overview</a></h2>
<p>As new virtualization engine support gets added to libvirt, and to
handle cases like QEMU supporting a variety of emulations, a query
interface has been added in 0.2.1 allowing to list the set of supported
virtualization capabilities on the host:</p>
<pre>char * virConnectGetCapabilities (virConnectPtr conn);</pre>
<p>The value returned is an XML document listing the virtualization
capabilities of the host and virtualization engine to which
<code>@conn</code> is connected. One can test it using <code>virsh</code>
command line tool command '<code>capabilities</code>', it dumps the XML
associated to the current connection. </p>
<p>As can be seen in the <a href="#elementExamples">example</a>, the
capabilities XML consists of the <code>capabilities</code> element which
have exactly one <code>host</code> child element to report information on
host capabilities, and zero or more <code>guest</code> element to express
the set of architectures the host can run at the moment.</p>
<h3><a id="elementHost">Host capabilities</a></h3>
<p>The <code>&lt;host/&gt;</code> element consists of the following child
elements:</p>
<dl>
<dt><code>uuid</code></dt>
<dd>The host UUID.</dd>
<dt><code>cpu</code></dt>
<dd>The host CPU architecture and features.</dd>
<dt><code>power_management</code></dt>
<dd>whether host is capable of memory suspend, disk hibernation, or
hybrid suspend.</dd>
<dt><code>migration_features</code></dt>
<dd>This element exposes information on the hypervisor's migration
capabilities, like live migration, supported URI transports, and so
on.</dd>
<dt><code>topology</code></dt>
<dd>This element embodies the host internal topology. Management
applications may want to learn this information when orchestrating new
guests - e.g. due to reduce inter-NUMA node transfers. Note that the
<code>sockets</code> value reported here is per-NUMA-node; this is in
contrast to the value given in domain definitions, which is interpreted
as a total number of sockets for the domain.</dd>
<dt><code>secmodel</code></dt>
<dd>To find out default security labels for different security models you
need to parse this element. In contrast with the former elements, this is
repeated for each security model the libvirt daemon currently supports.
</dd>
</dl>
<h3><a id="elementGuest">Guest capabilities</a></h3>
<p>While the <a href="#elementHost">previous section</a> aims at host
capabilities, this one focuses on capabilities available to a guest
using a given hypervisor. The <code>&lt;guest/&gt;</code> element will
typically wrap up the following elements:</p>
<dl>
<dt><code>os_type</code></dt>
<dd>This expresses what kind of operating system the hypervisor
is able to run. Possible values are:
<dl>
<dt><code>xen</code></dt>
<dd>for XEN PV</dd>
<dt><code>linux</code></dt>
<dd>legacy alias for <code>xen</code></dd>
<dt><code>xenpvh</code></dt>
<dd>for XEN PVH</dd>
<dt><code>hvm</code></dt>
<dd>Unmodified operating system</dd>
<dt><code>exe</code></dt>
<dd>Container based virtualization</dd>
</dl>
</dd>
<dt><code>arch</code></dt>
<dd>This element brings some information on supported guest
architecture. Possible subelements are:
<dl>
<dt><code>wordsize</code></dt><dd>Size of CPU word in bits, for example 64.</dd>
<dt><code>emulator</code></dt><dd>Emulator (device model) path, for
use in <a href="formatdomain.html#elementEmulator">emulator</a>
element of domain XML.</dd>
<dt><code>loader</code></dt><dd>Loader path, for use in
<a href="formatdomain.html#elementLoader">loader</a> element of domain
XML.</dd>
<dt><code>machine</code></dt><dd>Machine type, for use in
<a href="formatdomain.html#attributeOSTypeMachine">machine</a>
attribute of os/type element in domain XML. For example Xen
supports <code>xenfv</code> for HVM, <code>xenpv</code> for
PV, or <code>xenpvh</code> for PVH.</dd>
<dt><code>domain</code></dt><dd>The <code>type</code> attribute of
this element specifies the type of hypervisor required to run the
domain. Use in <a href="formatdomain.html#attributeDomainType">type</a>
attribute of the domain root element.</dd>
</dl>
</dd>
<dt><code>features</code></dt>
<dd>This optional element encases possible features that can be used
with a guest of described type. Possible subelements are:
<dl>
<dt><code>pae</code></dt><dd>If present, 32-bit guests can use PAE
address space extensions, <span class="since">since
0.4.1</span></dd>
<dt><code>nonpae</code></dt><dd>If present, 32-bit guests can be run
without requiring PAE, <span class="since">since
0.4.1</span></dd>
<dt><code>ia64_be</code></dt><dd>If present, IA64 guests can be run in
big-endian mode, <span class="since">since 0.4.1</span></dd>
<dt><code>acpi</code></dt><dd>If this element is present,
the <code>default</code> attribute describes whether the
hypervisor exposes ACPI to the guest by default, and
the <code>toggle</code> attribute describes whether the
user can override this
default. <span class="since">Since 0.4.1</span></dd>
<dt><code>apic</code></dt><dd>If this element is present,
the <code>default</code> attribute describes whether the
hypervisor exposes APIC to the guest by default, and
the <code>toggle</code> attribute describes whether the
user can override this
default. <span class="since">Since 0.4.1</span></dd>
<dt><code>cpuselection</code></dt><dd>If this element is present, the
hypervisor supports the <code>&lt;cpu&gt;</code> element
within a domain definition for fine-grained control over
the CPU presented to the
guest. <span class="since">Since 0.7.5</span></dd>
<dt><code>deviceboot</code></dt><dd>If this element is present,
the <code>&lt;boot order='...'/&gt;</code> element can
be used inside devices, rather than the older boot
specification by category. <span class="since">Since
0.8.8</span></dd>
<dt><code>disksnapshot</code></dt><dd>If this element is present,
the <code>default</code> attribute describes whether
external disk snapshots are supported. If absent,
external snapshots may still be supported, but it
requires attempting the API and checking for an error to
find out for sure. <span class="since">Since
1.2.3</span></dd>
</dl>
</dd>
</dl>
<h3><a id="elementExamples">Examples</a></h3>
<p>For example, in the case of a 64-bit machine with hardware
virtualization capabilities enabled in the chip and
BIOS you will see:</p>
<pre>&lt;capabilities&gt;
<span style="color: #E50000">&lt;host&gt;
&lt;cpu&gt;
&lt;arch&gt;x86_64&lt;/arch&gt;
&lt;features&gt;
&lt;vmx/&gt;
&lt;/features&gt;
&lt;model&gt;core2duo&lt;/model&gt;
&lt;vendor&gt;Intel&lt;/vendor&gt;
&lt;topology sockets="1" dies="1" cores="2" threads="1"/&gt;
&lt;feature name="lahf_lm"/&gt;
&lt;feature name='xtpr'/&gt;
...
&lt;/cpu&gt;
&lt;power_management&gt;
&lt;suspend_mem/&gt;
&lt;suspend_disk/&gt;
&lt;suspend_hybrid/&gt;
&lt;/power_management&gt;
&lt;/host&gt;</span>
&lt;!-- xen-3.0-x86_64 --&gt;
<span style="color: #0000E5">&lt;guest&gt;
&lt;os_type&gt;xen&lt;/os_type&gt;
&lt;arch name="x86_64"&gt;
&lt;wordsize&gt;64&lt;/wordsize&gt;
&lt;domain type="xen"&gt;&lt;/domain&gt;
&lt;emulator&gt;/usr/lib64/xen/bin/qemu-dm&lt;/emulator&gt;
&lt;/arch&gt;
&lt;features&gt;
&lt;/features&gt;
&lt;/guest&gt;</span>
&lt;!-- hvm-3.0-x86_32 --&gt;
<span style="color: #00B200">&lt;guest&gt;
&lt;os_type&gt;hvm&lt;/os_type&gt;
&lt;arch name="i686"&gt;
&lt;wordsize&gt;32&lt;/wordsize&gt;
&lt;domain type="xen"&gt;&lt;/domain&gt;
&lt;emulator&gt;/usr/lib/xen/bin/qemu-dm&lt;/emulator&gt;
&lt;machine&gt;pc&lt;/machine&gt;
&lt;machine&gt;isapc&lt;/machine&gt;
&lt;loader&gt;/usr/lib/xen/boot/hvmloader&lt;/loader&gt;
&lt;/arch&gt;
&lt;features&gt;
&lt;cpuselection/&gt;
&lt;deviceboot/&gt;
&lt;/features&gt;
&lt;/guest&gt;</span>
...
&lt;/capabilities&gt;</pre>
</body>
</html>

197
docs/formatcaps.rst Normal file
View File

@ -0,0 +1,197 @@
.. role:: since
==============================
Driver capabilities XML format
==============================
.. contents::
Element and attribute overview
------------------------------
As new virtualization engine support gets added to libvirt, and to handle cases
like QEMU supporting a variety of emulations, a query interface has been added
in 0.2.1 allowing to list the set of supported virtualization capabilities on
the host:
::
char * virConnectGetCapabilities (virConnectPtr conn);
The value returned is an XML document listing the virtualization capabilities of
the host and virtualization engine to which ```conn`` is connected. One can test
it using ``virsh`` command line tool command '``capabilities``', it dumps the
XML associated to the current connection.
As can be seen in the `Examples`_, the capabilities XML
consists of the ``capabilities`` element which have exactly one ``host`` child
element to report information on host capabilities, and zero or more ``guest``
element to express the set of architectures the host can run at the moment.
Host capabilities
~~~~~~~~~~~~~~~~~
The ``<host/>`` element consists of the following child elements:
``uuid``
The host UUID.
``cpu``
The host CPU architecture and features.
``power_management``
whether host is capable of memory suspend, disk hibernation, or hybrid
suspend.
``migration_features``
This element exposes information on the hypervisor's migration capabilities,
like live migration, supported URI transports, and so on.
``topology``
This element embodies the host internal topology. Management applications may
want to learn this information when orchestrating new guests - e.g. due to
reduce inter-NUMA node transfers. Note that the ``sockets`` value reported
here is per-NUMA-node; this is in contrast to the value given in domain
definitions, which is interpreted as a total number of sockets for the
domain.
``secmodel``
To find out default security labels for different security models you need to
parse this element. In contrast with the former elements, this is repeated
for each security model the libvirt daemon currently supports.
Guest capabilities
~~~~~~~~~~~~~~~~~~
While the previous section (`Host capabilities`_) aims at host capabilities,
this one focuses on capabilities available to a guest using a given hypervisor.
The ``<guest/>`` element will typically wrap up the following elements:
``os_type``
This expresses what kind of operating system the hypervisor is able to run.
Possible values are:
``xen``
for XEN PV
``linux``
legacy alias for ``xen``
``xenpvh``
for XEN PVH
``hvm``
Unmodified operating system
``exe``
Container based virtualization
``arch``
This element brings some information on supported guest architecture.
Possible subelements are:
``wordsize``
Size of CPU word in bits, for example 64.
``emulator``
Emulator (device model) path, for use in
`emulator <formatdomain.html#elementEmulator>`__ element of domain XML.
``loader``
Loader path, for use in `loader <formatdomain.html#elementLoader>`__
element of domain XML.
``machine``
Machine type, for use in
`machine <formatdomain.html#attributeOSTypeMachine>`__ attribute of
os/type element in domain XML. For example Xen supports ``xenfv`` for HVM,
``xenpv`` for PV, or ``xenpvh`` for PVH.
``domain``
The ``type`` attribute of this element specifies the type of hypervisor
required to run the domain. Use in
`type <formatdomain.html#attributeDomainType>`__ attribute of the domain
root element.
``features``
This optional element encases possible features that can be used with a guest
of described type. Possible subelements are:
``pae``
If present, 32-bit guests can use PAE address space extensions,
:since:`since 0.4.1`
``nonpae``
If present, 32-bit guests can be run without requiring PAE, :since:`since
0.4.1`
``ia64_be``
If present, IA64 guests can be run in big-endian mode, :since:`since
0.4.1`
``acpi``
If this element is present, the ``default`` attribute describes whether
the hypervisor exposes ACPI to the guest by default, and the ``toggle``
attribute describes whether the user can override this default.
:since:`Since 0.4.1`
``apic``
If this element is present, the ``default`` attribute describes whether
the hypervisor exposes APIC to the guest by default, and the ``toggle``
attribute describes whether the user can override this default.
:since:`Since 0.4.1`
``cpuselection``
If this element is present, the hypervisor supports the ``<cpu>`` element
within a domain definition for fine-grained control over the CPU presented
to the guest. :since:`Since 0.7.5`
``deviceboot``
If this element is present, the ``<boot order='...'/>`` element can be
used inside devices, rather than the older boot specification by category.
:since:`Since 0.8.8`
``disksnapshot``
If this element is present, the ``default`` attribute describes whether
external disk snapshots are supported. If absent, external snapshots may
still be supported, but it requires attempting the API and checking for an
error to find out for sure. :since:`Since 1.2.3`
Examples
~~~~~~~~
For example, in the case of a 64-bit machine with hardware virtualization
capabilities enabled in the chip and BIOS you will see:
::
<capabilities>
<host>
<cpu>
<arch>x86_64</arch>
<features>
<vmx/>
</features>
<model>core2duo</model>
<vendor>Intel</vendor>
<topology sockets="1" dies="1" cores="2" threads="1"/>
<feature name="lahf_lm"/>
<feature name='xtpr'/>
...
</cpu>
<power_management>
<suspend_mem/>
<suspend_disk/>
<suspend_hybrid/>
</power_management>
</host>
<!-- xen-3.0-x86_64 -->
<guest>
<os_type>xen</os_type>
<arch name="x86_64">
<wordsize>64</wordsize>
<domain type="xen"></domain>
<emulator>/usr/lib64/xen/bin/qemu-dm</emulator>
</arch>
<features>
</features>
</guest>
<!-- hvm-3.0-x86_32 -->
<guest>
<os_type>hvm</os_type>
<arch name="i686">
<wordsize>32</wordsize>
<domain type="xen"></domain>
<emulator>/usr/lib/xen/bin/qemu-dm</emulator>
<machine>pc</machine>
<machine>isapc</machine>
<loader>/usr/lib/xen/boot/hvmloader</loader>
</arch>
<features>
<cpuselection/>
<deviceboot/>
</features>
</guest>
...
</capabilities>

View File

@ -18,7 +18,6 @@ docs_assets = [
]
docs_html_in_files = [
'formatcaps',
'formatnetwork',
'formatnode',
'index',
@ -69,6 +68,7 @@ docs_rst_files = [
'firewall',
'format',
'formatbackup',
'formatcaps',
'formatcheckpoint',
'formatdomain',
'formatdomaincaps',