On Tue, 22 Dec 2020 20:15:58 -0500 Tony Krowiak <akrowiak@xxxxxxxxxxxxx> wrote: > The APCB is a field within the CRYCB that provides the AP configuration > to a KVM guest. Let's introduce a shadow copy of the KVM guest's APCB and > maintain it for the lifespan of the guest. > > Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx> > Reviewed-by: Halil Pasic <pasic@xxxxxxxxxxxxx> > --- > drivers/s390/crypto/vfio_ap_ops.c | 15 +++++++++++++++ > drivers/s390/crypto/vfio_ap_private.h | 2 ++ > 2 files changed, 17 insertions(+) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index 2d58b39977be..44b3a81cadfb 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -293,6 +293,20 @@ static void vfio_ap_matrix_init(struct ap_config_info *info, > matrix->adm_max = info->apxa ? info->Nd : 15; > } > > +static bool vfio_ap_mdev_has_crycb(struct ap_matrix_mdev *matrix_mdev) > +{ > + return (matrix_mdev->kvm && matrix_mdev->kvm->arch.crypto.crycbd); > +} > + > +static void vfio_ap_mdev_commit_shadow_apcb(struct ap_matrix_mdev *matrix_mdev) > +{ > + if (vfio_ap_mdev_has_crycb(matrix_mdev)) > + kvm_arch_crypto_set_masks(matrix_mdev->kvm, > + matrix_mdev->shadow_apcb.apm, > + matrix_mdev->shadow_apcb.aqm, > + matrix_mdev->shadow_apcb.adm); > +} > + > static int vfio_ap_mdev_create(struct kobject *kobj, struct mdev_device *mdev) > { > struct ap_matrix_mdev *matrix_mdev; > @@ -308,6 +322,7 @@ static int vfio_ap_mdev_create(struct kobject *kobj, struct mdev_device *mdev) > > matrix_mdev->mdev = mdev; > vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->matrix); > + vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->shadow_apcb); > hash_init(matrix_mdev->qtable); > mdev_set_drvdata(mdev, matrix_mdev); > matrix_mdev->pqap_hook.hook = handle_pqap; > diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h > index 4e5cc72fc0db..d2d26ba18602 100644 > --- a/drivers/s390/crypto/vfio_ap_private.h > +++ b/drivers/s390/crypto/vfio_ap_private.h > @@ -75,6 +75,7 @@ struct ap_matrix { > * @list: allows the ap_matrix_mdev struct to be added to a list > * @matrix: the adapters, usage domains and control domains assigned to the > * mediated matrix device. > + * @shadow_apcb: the shadow copy of the APCB field of the KVM guest's CRYCB > * @group_notifier: notifier block used for specifying callback function for > * handling the VFIO_GROUP_NOTIFY_SET_KVM event > * @kvm: the struct holding guest's state > @@ -82,6 +83,7 @@ struct ap_matrix { > struct ap_matrix_mdev { > struct list_head node; > struct ap_matrix matrix; > + struct ap_matrix shadow_apcb; > struct notifier_block group_notifier; > struct notifier_block iommu_notifier; > struct kvm *kvm; What happened to the following hunk from v12? @@ -1218,13 +1233,9 @@ static int vfio_ap_mdev_group_notifier(struct notifier_block *nb, if (ret) return NOTIFY_DONE; - /* If there is no CRYCB pointer, then we can't copy the masks */ - if (!matrix_mdev->kvm->arch.crypto.crycbd) - return NOTIFY_DONE; - - kvm_arch_crypto_set_masks(matrix_mdev->kvm, matrix_mdev->matrix.apm, - matrix_mdev->matrix.aqm, - matrix_mdev->matrix.adm); + memcpy(&matrix_mdev->shadow_apcb, &matrix_mdev->matrix, + sizeof(matrix_mdev->shadow_apcb)); + vfio_ap_mdev_commit_shadow_apcb(matrix_mdev); return NOTIFY_OK; }