At the moment VFIO PCI device initialization works as follows: vfio_realize vfio_get_group vfio_connect_container register memory listeners (1) update QEMU groups lists vfio_kvm_device_add_group Then (example for pseries) the machine reset hook triggers region_add() for all regions where listeners from (1) are listening: ppc_spapr_reset spapr_phb_reset spapr_tce_table_enable memory_region_add_subregion vfio_listener_region_add vfio_spapr_create_window This scheme works fine until we need to handle VFIO PCI device hotplug and we want to enable PPC64/sPAPR in-kernel TCE acceleration on, i.e. after PCI hotplug we need a place to call ioctl(vfio_kvm_device_fd, KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE). Since the ioctl needs a LIOBN fd (from sPAPRTCETable) and a IOMMU group fd (from VFIOGroup), vfio_listener_region_add() seems to be the only place for this ioctl(). However this only works during boot time because the machine reset happens strictly after all devices are finalized. When hotplug happens, vfio_listener_region_add() is called when a memory listener is registered but when this happens: 1. new group is not added to the container->group_list yet; 2. VFIO KVM device is unaware of the new IOMMU group. This moves bits around to have all necessary VFIO infrastructure in place for both initial startup and hotplug cases. [aw: ie, register vfio groups with kvm prior to memory listener registration such that kvm-vfio pseudo device ioctls are available during the region_add callback] Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> |
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amd-xgbe.c | ||
calxeda-xgmac.c | ||
ccw.c | ||
common.c | ||
Makefile.objs | ||
pci-quirks.c | ||
pci.c | ||
pci.h | ||
platform.c | ||
spapr.c | ||
trace-events |