vfio/ccw: Allow the selection of a given iommu backend

Now we support two types of iommu backends, let's add the capability
to select one of them. This depends on whether an iommufd object has
been linked with the vfio-ccw device:

If the user wants to use the legacy backend, it shall not
link the vfio-ccw device with any iommufd object:

 -device vfio-ccw,sysfsdev=/sys/bus/mdev/devices/XXX

This is called the legacy mode/backend.

If the user wants to use the iommufd backend (/dev/iommu) it
shall pass an iommufd object id in the vfio-ccw device options:

 -object iommufd,id=iommufd0
 -device vfio-ccw,sysfsdev=/sys/bus/mdev/devices/XXX,iommufd=iommufd0

Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
This commit is contained in:
Zhenzhong Duan 2023-11-21 16:44:15 +08:00 committed by Cédric Le Goater
parent 5e7ba401b7
commit e70f971a6c

View File

@ -15,12 +15,14 @@
*/
#include "qemu/osdep.h"
#include CONFIG_DEVICES /* CONFIG_IOMMUFD */
#include <linux/vfio.h>
#include <linux/vfio_ccw.h>
#include <sys/ioctl.h>
#include "qapi/error.h"
#include "hw/vfio/vfio-common.h"
#include "sysemu/iommufd.h"
#include "hw/s390x/s390-ccw.h"
#include "hw/s390x/vfio-ccw.h"
#include "hw/qdev-properties.h"
@ -677,6 +679,10 @@ static void vfio_ccw_unrealize(DeviceState *dev)
static Property vfio_ccw_properties[] = {
DEFINE_PROP_STRING("sysfsdev", VFIOCCWDevice, vdev.sysfsdev),
DEFINE_PROP_BOOL("force-orb-pfch", VFIOCCWDevice, force_orb_pfch, false),
#ifdef CONFIG_IOMMUFD
DEFINE_PROP_LINK("iommufd", VFIOCCWDevice, vdev.iommufd,
TYPE_IOMMUFD_BACKEND, IOMMUFDBackend *),
#endif
DEFINE_PROP_END_OF_LIST(),
};