Rather than always binding to the vfio-pci driver, use the new function virPCIDeviceFindBestVFIOVariant() to see if the running kernel has a VFIO variant driver available that is a better match for the device, and if one is found, use that instead. virPCIDeviceFindBestVFIOVariant() function reads the modalias file for the given device from sysfs, then looks through /lib/modules/${kernel_release}/modules.alias for the vfio_pci alias that matches with the least number of wildcard ('*') fields. The appropriate "VFIO variant" driver for a device will be the PCI driver implemented by the discovered module - these drivers are compatible with (and provide the entire API of) the standard vfio-pci driver, but have additional device-specific APIs that can be useful for, e.g., saving/restoring state for migration. If a specific driver is named (using <driver model='blah'/> in the device XML), that will still be used rather than searching modules.alias; this makes it possible to force binding of vfio-pci if there is an issue with the auto-selected variant driver. Signed-off-by: Laine Stump <laine@redhat.com> Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Libvirt API for virtualization
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.
For some of these hypervisors, it provides a stateful management daemon which runs on the virtualization host allowing access to the API both by non-privileged local users and remote users.
Layered packages provide bindings of the libvirt C API into other languages including Python, Perl, PHP, Go, Java, OCaml, as well as mappings into object systems such as GObject, CIM and SNMP.
Further information about the libvirt project can be found on the website:
License
The libvirt C API is distributed under the terms of GNU Lesser General Public License, version 2.1 (or later). Some parts of the code that are not part of the C library may have the more restrictive GNU General Public License, version 2.0 (or later). See the files COPYING.LESSER
and COPYING
for full license terms & conditions.
Installation
Instructions on building and installing libvirt can be found on the website:
https://libvirt.org/compiling.html
Contributing
The libvirt project welcomes contributions in many ways. For most components the best way to contribute is to send patches to the primary development mailing list. Further guidance on this can be found on the website:
https://libvirt.org/contribute.html
Contact
The libvirt project has two primary mailing lists:
- users@lists.libvirt.org (for user discussions)
- devel@lists.libvirt.org (for development only)
Further details on contacting the project are available on the website: