On Tue, 9 Jul 2019 15:19:12 +0530 Kirti Wankhede <kwankh...@nvidia.com> wrote:
> - Migration functions are implemented for VFIO_DEVICE_TYPE_PCI device in this > patch series. > - VFIO device supports migration or not is decided based of migration region > query. If migration region query is successful and migration region > initialization is successful then migration is supported else migration is > blocked. > > Signed-off-by: Kirti Wankhede <kwankh...@nvidia.com> > Reviewed-by: Neo Jia <c...@nvidia.com> > --- > hw/vfio/Makefile.objs | 2 +- > hw/vfio/migration.c | 145 > ++++++++++++++++++++++++++++++++++++++++++ > hw/vfio/trace-events | 3 + > include/hw/vfio/vfio-common.h | 14 ++++ > 4 files changed, 163 insertions(+), 1 deletion(-) > create mode 100644 hw/vfio/migration.c > (...) > diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c > new file mode 100644 > index 000000000000..a2cfbd5af2e1 > --- /dev/null > +++ b/hw/vfio/migration.c > @@ -0,0 +1,145 @@ > +/* > + * Migration support for VFIO devices > + * > + * Copyright NVIDIA, Inc. 2019 > + * > + * This work is licensed under the terms of the GNU GPL, version 2. See > + * the COPYING file in the top-level directory. > + */ > + > +#include "qemu/osdep.h" > +#include <linux/vfio.h> > + > +#include "hw/vfio/vfio-common.h" > +#include "cpu.h" > +#include "migration/migration.h" > +#include "migration/qemu-file.h" > +#include "migration/register.h" > +#include "migration/blocker.h" > +#include "migration/misc.h" > +#include "qapi/error.h" > +#include "exec/ramlist.h" > +#include "exec/ram_addr.h" > +#include "pci.h" > +#include "trace.h" > + > +static void vfio_migration_region_exit(VFIODevice *vbasedev) > +{ > + VFIOMigration *migration = vbasedev->migration; > + > + if (!migration) { > + return; > + } > + > + if (migration->region.buffer.size) { > + vfio_region_exit(&migration->region.buffer); > + vfio_region_finalize(&migration->region.buffer); > + } > +} > + > +static int vfio_migration_region_init(VFIODevice *vbasedev) > +{ > + VFIOMigration *migration = vbasedev->migration; > + Object *obj = NULL; > + int ret = -EINVAL; > + > + if (!migration) { You're checking for vbasedev->migration here... > + return ret; > + } > + > + if (!vbasedev->ops || !vbasedev->ops->vfio_get_object) { > + return ret; > + } > + > + obj = vbasedev->ops->vfio_get_object(vbasedev); > + if (!obj) { > + return ret; > + } > + > + ret = vfio_region_setup(obj, vbasedev, &migration->region.buffer, > + migration->region.index, "migration"); > + if (ret) { > + error_report("%s: Failed to setup VFIO migration region %d: %s", > + vbasedev->name, migration->region.index, > strerror(-ret)); > + goto err; > + } > + > + if (!migration->region.buffer.size) { > + ret = -EINVAL; > + error_report("%s: Invalid region size of VFIO migration region %d: > %s", > + vbasedev->name, migration->region.index, > strerror(-ret)); > + goto err; > + } > + > + return 0; > + > +err: > + vfio_migration_region_exit(vbasedev); > + return ret; > +} > + > +static int vfio_migration_init(VFIODevice *vbasedev, > + struct vfio_region_info *info) > +{ > + int ret; > + > + vbasedev->migration = g_new0(VFIOMigration, 1); ...but always allocate it before calling the function above here. What am I missing? > + vbasedev->migration->region.index = info->index; > + > + ret = vfio_migration_region_init(vbasedev); > + if (ret) { > + error_report("%s: Failed to initialise migration region", > + vbasedev->name); > + return ret; It feels a bit odd that you don't free ->migration again here, but delay it until finalize. > + } > + > + return 0; > +} > + > +/* ---------------------------------------------------------------------- */ > + > +int vfio_migration_probe(VFIODevice *vbasedev, Error **errp) > +{ > + struct vfio_region_info *info; > + Error *local_err = NULL; > + int ret; > + > + ret = vfio_get_dev_region_info(vbasedev, VFIO_REGION_TYPE_MIGRATION, > + VFIO_REGION_SUBTYPE_MIGRATION, &info); > + if (ret) { > + goto add_blocker; So you don't even call init if the region is not present (which seems reasonable)... > + } > + > + ret = vfio_migration_init(vbasedev, info); > + if (ret) { > + goto add_blocker; > + } > + > + trace_vfio_migration_probe(vbasedev->name, info->index); > + return 0; > + > +add_blocker: > + error_setg(&vbasedev->migration_blocker, > + "VFIO device doesn't support migration"); > + ret = migrate_add_blocker(vbasedev->migration_blocker, &local_err); > + if (local_err) { > + error_propagate(errp, local_err); > + error_free(vbasedev->migration_blocker); > + } > + return ret; > +} > + > +void vfio_migration_finalize(VFIODevice *vbasedev) > +{ > + if (!vbasedev->migration) { ...but you're doing a quick exit here in that case. Shouldn't you get rid of the blocker here? > + return; > + } > + > + if (vbasedev->migration_blocker) { > + migrate_del_blocker(vbasedev->migration_blocker); > + error_free(vbasedev->migration_blocker); > + } > + > + vfio_migration_region_exit(vbasedev); > + g_free(vbasedev->migration); > +}