From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:7252 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726729AbhANVfu (ORCPT ); Thu, 14 Jan 2021 16:35:50 -0500 Subject: Re: [PATCH v13 07/15] s390/vfio-ap: introduce shadow APCB References: <20201223011606.5265-1-akrowiak@linux.ibm.com> <20201223011606.5265-8-akrowiak@linux.ibm.com> <20210111235058.32ed94b5.pasic@linux.ibm.com> From: Tony Krowiak Message-ID: <47a353f5-e34f-db7b-65da-6fcf405959d5@linux.ibm.com> Date: Thu, 14 Jan 2021 16:35:01 -0500 MIME-Version: 1.0 In-Reply-To: <20210111235058.32ed94b5.pasic@linux.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US List-ID: To: Halil Pasic Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, freude@linux.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.com, mjrosato@linux.ibm.com, alex.williamson@redhat.com, kwankhede@nvidia.com, fiuczy@linux.ibm.com, frankja@linux.ibm.com, david@redhat.com, hca@linux.ibm.com, gor@linux.ibm.com On 1/11/21 5:50 PM, Halil Pasic wrote: > On Tue, 22 Dec 2020 20:15:58 -0500 > Tony Krowiak 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 >> Reviewed-by: Halil Pasic >> --- >> 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? That's a very good question, I'll reinstate it. > > @@ -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; > }