Re: [libvirt] [PATCH 3/3] conf: formatter/parser/RNG/docs for hostdev <driver name='kvm|vfio'/>

A domain's <interface> or <hostdev>, as well as a <network>'s <forward>, can now have an optional <driver name='kvm|vfio'/> element. As of this patch, there is no functionality behind this new knob - this patch adds support to the domain and network formatter/parser, and to the RNG and documentation. When then backend is added, legacy KVM PCI device assignment will

continue to be used when no driver name is specified (or if <driver name='kvm'/> is specified), but if driver name is 'vfio', the new UEFI Secure Boot compatible VFIO device assignment will be used. Note that the parser doesn't automatically insert the current default value of this setting. This is done on purpose because the two possibilities are functionally equivalent from the guest's point of view, and we want to be able to automatically start using vfio as the default (even for existing domains) at some time in the future. This is similar to what was done with the "vhost" driver option in <interface>.

--- docs/formatdomain.html.in | 42 ++++++++++++++++++++++- docs/formatnetwork.html.in | 15 ++++++++ docs/schemas/domaincommon.rng | 79 ++++++++++++++++++++++++++++--------------- docs/schemas/network.rng | 11 ++++++ src/conf/domain_conf.c | 36 ++++++++++++++++++++ src/conf/domain_conf.h | 11 ++++++ 6 files changed, 166 insertions(+), 28 deletions(-) diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in index 888c005..0e5b00c 100644 --- a/docs/formatdomain.html.in +++ b/docs/formatdomain.html.in @@ -2340,7 +2340,22 @@ the device as can be found with the <code>lspci</code> or with <code>virsh nodedev-list</code>. <a href="#elementsAddress">See above</a> for - more details on the address element. + more details on the address element.</dd> + <dt><code>driver</code></dt> + <dd> + PCI devices can have an optional <code>driver</code> + subelement that specifies which backend driver to use for PCI + device assignment. Use the <code>name</code> attribute to + select either "vfio" (for the new VFIO device assignment + backend, which is compatible with UEFI SecureBoot) or "kvm" + (for the legacy device assignment handled directly by the KVM + kernel module)<span class="since">Since 1.0.5 (QEMU and KVM + only, requires kernel 3.6 or newer)</span>. Currently, "kvm" + is the default used by libvirt when not explicitly provided, + but since the two are functionally equivalent, this default + could be changed in the future with no impact to domains that + don't specify anything.

+ device assignment performed directly by the kvm kernel module + (the default is currently "kvm", but is subject to change). + <span class="since">Since 1.0.5 (QEMU and KVM only, requires kernel 3.6 or newer)</span>

+++ b/docs/schemas/domaincommon.rng @@ -1923,28 +1923,40 @@ </optional> <optional> <element name="driver"> - <optional> - <attribute name="name"> - <choice> - <value>qemu</value> - <value>vhost</value> - </choice> - </attribute> - </optional> - <optional> - <attribute name="txmode"> - <choice> - <value>iothread</value> - <value>timer</value> - </choice> - </attribute> - </optional> - <optional> - <ref name="ioeventfd"/> - </optional> - <optional> - <ref name="event_idx"/> - </optional> + <choice> + <group> + <attribute name="name"> + <choice> + <value>kvm</value> + <value>vfio</value> + </choice> + </attribute> + </group> + <group> + <optional> + <attribute name="name"> + <choice> + <value>qemu</value> + <value>vhost</value>

+ </choice> + </attribute> + </optional> + <optional> + <attribute name="txmode"> + <choice> + <value>iothread</value> + <value>timer</value> + </choice> + </attribute> + </optional> + <optional> + <ref name="ioeventfd"/> + </optional> + <optional> + <ref name="event_idx"/> + </optional> + </group> + </choice> <empty/> </element> </optional> @@ -3084,14 +3096,27 @@ <attribute name="type"> <value>pci</value> </attribute> - <element name="source"> + <interleave> <optional> - <ref name="startupPolicy"/> + <element name="driver"> + <attribute name="name"> + <choice> + <value>kvm</value> + <value>vfio</value> + </choice> + </attribute> + <empty/>

+ </element> </optional> - <element name="address"> - <ref name="pciaddress"/> + <element name="source"> + <optional> + <ref name="startupPolicy"/> + </optional> + <element name="address"> + <ref name="pciaddress"/> + </element> </element> - </element> + </interleave> </define> <define name="hostdevsubsysusb"> diff --git a/docs/schemas/network.rng b/docs/schemas/network.rng index 6c3fae2..493edae 100644 --- a/docs/schemas/network.rng +++ b/docs/schemas/network.rng @@ -149,6 +149,17 @@ </attribute> </element> </optional> + <optional> + <element name="driver"> + <attribute name="name"> + <choice> + <value>kvm</value> + <value>vfio</value> + </choice> + </attribute> + <empty/> + </element> + </optional> </interleave>