Xen only supports a single type of PCI hostdev assignment, so it is
superfluous to have <driver name='xen'/> peppered throughout the
config. It *is* necessary to have the driver type explicitly set in
the hostdev object before calling into the hypervisor-agnostic "hostdev
manager" though (otherwise the hostdev manager doesn't know whether it
should do Xen-specific setup, or VFIO-specific setup).
Historically, the Xen driver has checked for "default" driver name
(i.e. not set in the XML), and set it to "xen', during the XML
postparse, thus guaranteeing that it will be set by the time the
object is sent to the hostdev manager at runtime, but also setting it
so early that a simple round-trip of parse-format results in the XML
always containing an explicit <driver name='xen'/>, even if that
wasn't specified in the original XML.
The QEMU driver *doesn't* set driver.name during postparse though;
instead, it waits until domain startup time (or device attach time for
hotplug), and sets the driver.name then. The result is that a
parse-format round trip of the XML in the QEMU driver *doesn't* add in
the <driver name='vfio'/>.
This patch modifies the Xen driver to behave similarly to the QEMU
driver - the PostParse just checks for a driver.name that isn't
supported by the Xen driver, and any explicit setting to "xen" is
deferred until domain runtime rather than during the postparse, thus
Xen domain XML also doesn't get extraneous <driver name='xen'/>.
This delayed setting of driver.name of course results in slightly
different xml2xml parse-format results, so the unit test data is
modified accordingly.
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
By default Xen only allows guests to write "known safe" values into PCI
configuration space, yet many devices require writes to other areas of
the configuration space in order to operate properly. To allow writing
any values Xen supports the 'permissive' setting, see xl.cfg(5) man page.
This change models Xen's permissive setting by adding a writeFiltering
attribute on the <source> element of a PCI hostdev. When writeFiltering
is set to 'no', the Xen permissive setting will be enabled and guests
will be able to write any values into the device's configuration space.
The permissive setting remains disabled in the absense of the
writeFiltering attribute, of if it is explicitly set to 'yes'.
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com>
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The libxl library allows a libxl_domain_config object to be serialized
from/to a JSON string. Use this to allow testing of the XML to
libxl_domain_config conversion process. Test XML is converted to
libxl_domain_config, which is then serialized to json. A json template
corresponding to the test XML is converted to a libxl_domain_config
object using libxl_domain_config_from_json(), and then serialized
back to json using libxl_domain_config_to_json(). The two json
docs are then compared.
Using libxl to convert the json template to a libxl_domain_config
object and then back to json provides a simple way to account for
any changes or additions to the json representation across Xen
releases.
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
[update to v3.5.0-rc1, improve error reporting, use /bin/true emulator]
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
