On Tue, 7 Mar 2023 09:38:51 -0700 Alex Williamson <[email protected]> wrote:
> On Tue, 7 Mar 2023 12:54:48 +0000 > Joao Martins <[email protected]> wrote: > > > Migrating with vIOMMU will require either tracking maximum > > IOMMU supported address space (e.g. 39/48 address width on Intel) > > or range-track current mappings and dirty track the new ones > > post starting dirty tracking. This will be done as a separate > > series, so add a live migration blocker until that is fixed. > > > > Signed-off-by: Joao Martins <[email protected]> > > Reviewed-by: Cédric Le Goater <[email protected]> > > --- > > hw/vfio/common.c | 46 +++++++++++++++++++++++++++++++++++ > > hw/vfio/migration.c | 5 ++++ > > hw/vfio/pci.c | 1 + > > include/hw/vfio/vfio-common.h | 2 ++ > > 4 files changed, 54 insertions(+) > > > > diff --git a/hw/vfio/common.c b/hw/vfio/common.c > > index 2639b393a781..2b9bcf70aa36 100644 > > --- a/hw/vfio/common.c > > +++ b/hw/vfio/common.c > > @@ -362,6 +362,7 @@ bool vfio_mig_active(void) > > } > > > > static Error *multiple_devices_migration_blocker; > > +static Error *giommu_migration_blocker; > > > > static unsigned int vfio_migratable_device_num(void) > > { > > @@ -413,6 +414,51 @@ void vfio_unblock_multiple_devices_migration(void) > > multiple_devices_migration_blocker = NULL; > > } > > > > +static bool vfio_viommu_preset(void) > > +{ > > + VFIOAddressSpace *space; > > + > > + QLIST_FOREACH(space, &vfio_address_spaces, list) { > > + if (space->as != &address_space_memory) { > > + return true; > > + } > > + } > > + > > + return false; > > +} > > + > > +int vfio_block_giommu_migration(Error **errp) > > +{ > > + int ret; > > + > > + if (giommu_migration_blocker || > > + !vfio_viommu_preset()) { > > + return 0; > > + } > > + > > + error_setg(&giommu_migration_blocker, > > + "Migration is currently not supported with vIOMMU enabled"); > > + ret = migrate_add_blocker(giommu_migration_blocker, errp); > > + if (ret < 0) { > > + error_free(giommu_migration_blocker); > > + giommu_migration_blocker = NULL; > > + } > > + > > + return ret; > > +} > > + > > +void vfio_unblock_giommu_migration(void) > > +{ > > + if (!giommu_migration_blocker || > > + vfio_viommu_preset()) { > > + return; > > + } > > + > > + migrate_del_blocker(giommu_migration_blocker); > > + error_free(giommu_migration_blocker); > > + giommu_migration_blocker = NULL; > > +} > > + > > static void vfio_set_migration_error(int err) > > { > > MigrationState *ms = migrate_get_current(); > > diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c > > index a2c3d9bade7f..776fd2d7cdf3 100644 > > --- a/hw/vfio/migration.c > > +++ b/hw/vfio/migration.c > > @@ -634,6 +634,11 @@ int vfio_migration_probe(VFIODevice *vbasedev, Error > > **errp) > > return ret; > > } > > > > + ret = vfio_block_giommu_migration(errp); > > + if (ret) { > > + return ret; > > + } > > + > > trace_vfio_migration_probe(vbasedev->name); > > return 0; > > > > diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c > > index 939dcc3d4a9e..30a271eab38c 100644 > > --- a/hw/vfio/pci.c > > +++ b/hw/vfio/pci.c > > @@ -3185,6 +3185,7 @@ static void vfio_instance_finalize(Object *obj) > > */ > > vfio_put_device(vdev); > > vfio_put_group(group); > > + vfio_unblock_giommu_migration(); > > } > > Hmm, doesn't this mean we're adding the viommu migration blocker in > common code but only removing it in pci code? Granted that only PCI > devices currently have IOMMUs, but ick. Thanks, Or maybe the justification is that vfio_migration_probe() is also only called by the vfio-pci vfio_realize(), so it's more symmetric than it appears. Ok. Thanks, Alex
