VFIO virtual device

Device types supported:

  • KVM_DEV_TYPE_VFIO

Only one VFIO instance may be created per VM. The created device tracks VFIO groups in use by the VM and features of those groups important to the correctness and acceleration of the VM. As groups are enabled and disabled for use by the VM, KVM should be updated about their presence. When registered with KVM, a reference to the VFIO-group is held by KVM.

Groups:

KVM_DEV_VFIO_GROUP

KVM_DEV_VFIO_GROUP attributes:
KVM_DEV_VFIO_GROUP_ADD: Add a VFIO group to VFIO-KVM device tracking

kvm_device_attr.addr points to an int32_t file descriptor for the VFIO group.

KVM_DEV_VFIO_GROUP_DEL: Remove a VFIO group from VFIO-KVM device tracking

kvm_device_attr.addr points to an int32_t file descriptor for the VFIO group.

KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE: attaches a guest visible TCE table

allocated by sPAPR KVM. kvm_device_attr.addr points to a struct:

struct kvm_vfio_spapr_tce {
        __s32   groupfd;
        __s32   tablefd;
};

where:

  • @groupfd is a file descriptor for a VFIO group;

  • @tablefd is a file descriptor for a TCE table allocated via KVM_CREATE_SPAPR_TCE.