From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B45B6C43381 for ; Fri, 15 Feb 2019 22:55:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7D5F0222DD for ; Fri, 15 Feb 2019 22:55:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394232AbfBOWzr (ORCPT ); Fri, 15 Feb 2019 17:55:47 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:51228 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728235AbfBOWzq (ORCPT ); Fri, 15 Feb 2019 17:55:46 -0500 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1FMccE3176619 for ; Fri, 15 Feb 2019 17:55:45 -0500 Received: from e16.ny.us.ibm.com (e16.ny.us.ibm.com [129.33.205.206]) by mx0b-001b2d01.pphosted.com with ESMTP id 2qp59samme-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 15 Feb 2019 17:55:44 -0500 Received: from localhost by e16.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 15 Feb 2019 22:55:40 -0000 Received: from b01ledav005.gho.pok.ibm.com (b01ledav005.gho.pok.ibm.com [9.57.199.110]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x1FMtbo724445034 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 15 Feb 2019 22:55:37 GMT Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 006C3AE062; Fri, 15 Feb 2019 22:55:37 +0000 (GMT) Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 45CE6AE060; Fri, 15 Feb 2019 22:55:36 +0000 (GMT) Received: from [9.80.239.175] (unknown [9.80.239.175]) by b01ledav005.gho.pok.ibm.com (Postfix) with ESMTP; Fri, 15 Feb 2019 22:55:36 +0000 (GMT) Subject: Re: [PATCH v3 6/9] vfio: ap: register IOMMU VFIO notifier To: Pierre Morel , borntraeger@de.ibm.com Cc: alex.williamson@redhat.com, cohuck@redhat.com, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, kvm@vger.kernel.org, frankja@linux.ibm.com, pasic@linux.ibm.com, david@redhat.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, freude@linux.ibm.com, mimu@linux.ibm.com References: <1550152269-6317-1-git-send-email-pmorel@linux.ibm.com> <1550152269-6317-7-git-send-email-pmorel@linux.ibm.com> From: Tony Krowiak Date: Fri, 15 Feb 2019 17:55:35 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <1550152269-6317-7-git-send-email-pmorel@linux.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 19021522-0072-0000-0000-000003FAB960 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00010604; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000280; SDB=6.01161606; UDB=6.00606365; IPR=6.00942166; MB=3.00025605; MTD=3.00000008; XFM=3.00000015; UTC=2019-02-15 22:55:43 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19021522-0073-0000-0000-00004B31B5B3 Message-Id: <3ce0a3a0-22fb-c418-321d-7e6e3af5b66c@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-15_16:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1902150147 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/14/19 8:51 AM, Pierre Morel wrote: > To be able to use the VFIO interface to facilitate the > mediated device memory pining/unpining we need to register > a notifier for IOMMU. > > Signed-off-by: Pierre Morel > --- > drivers/s390/crypto/vfio_ap_ops.c | 64 +++++++++++++++++++++++++++++++---- > drivers/s390/crypto/vfio_ap_private.h | 2 ++ > 2 files changed, 60 insertions(+), 6 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index 1851b24..6eddc2c 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -781,6 +781,36 @@ static const struct attribute_group *vfio_ap_mdev_attr_groups[] = { > }; > > /** > + * vfio_ap_mdev_iommu_notifier: IOMMU notifier callback > + * > + * @nb: The notifier block > + * @action: Action to be taken (VFIO_IOMMU_NOTIFY_DMA_UNMAP) > + * @data: the specific unmap structure for vfio_iommu_type1 > + * > + * Unpins the guest IOVA. (The NIB guest address we pinned before). > + * Return NOTIFY_OK after unpining on a UNMAP request. > + * otherwise, returns NOTIFY_DONE . > + */ > +static int vfio_ap_mdev_iommu_notifier(struct notifier_block *nb, > + unsigned long action, void *data) > +{ > + struct ap_matrix_mdev *matrix_mdev; > + > + matrix_mdev = container_of(nb, struct ap_matrix_mdev, iommu_notifier); > + > + if (action == VFIO_IOMMU_NOTIFY_DMA_UNMAP) { > + struct vfio_iommu_type1_dma_unmap *unmap = data; > + unsigned long g_pfn = unmap->iova >> PAGE_SHIFT; > + > + vfio_unpin_pages(mdev_dev(matrix_mdev->mdev), &g_pfn, 1); > + return NOTIFY_OK; > + } > + > + return NOTIFY_DONE; > +} > + > + > +/** > * vfio_ap_mdev_set_kvm > * > * @matrix_mdev: a mediated matrix device > @@ -904,8 +934,7 @@ static void vfio_ap_dissociate_queues(struct ap_matrix_mdev *matrix_mdev) > * In the case a queue could not be found return -ENODEV. > * Otherwise return 0. > */ > -static __attribute__((unused)) > - int vfio_ap_associate_queues(struct ap_matrix_mdev *matrix_mdev) > +static int vfio_ap_associate_queues(struct ap_matrix_mdev *matrix_mdev) Maybe this function should be introduced in this patch instead? > { > unsigned long apid, apqi; > struct vfio_ap_queue *q; > @@ -967,12 +996,32 @@ static int vfio_ap_mdev_open(struct mdev_device *mdev) > > ret = vfio_register_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY, > &events, &matrix_mdev->group_notifier); > - if (ret) { > - module_put(THIS_MODULE); > - return ret; > - } > + if (ret) > + goto err_group; > + > + matrix_mdev->iommu_notifier.notifier_call = vfio_ap_mdev_iommu_notifier; > + events = VFIO_IOMMU_NOTIFY_DMA_UNMAP; > + > + ret = vfio_register_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, > + &events, &matrix_mdev->iommu_notifier); > + if (ret) > + goto err_iommu; > + > + ret = vfio_ap_associate_queues(matrix_mdev); > + if (ret) > + goto err_associate; I think the matrix_mdev should be associated with queues when an assignment of an adapter or domain is made to the mdev device via its sysfs interfaces. I say this because assigning an adapter or domain to an mdev device effectively grants ownership of any additional AP queues added to the mdev device's AP matrix as a result of the assignment. It only makes sense to assign ownership to the vfio_ap_queue objects representing the queues at that time. If an adapter or domain is dynamically assigned while a guest is using the affected queues, then the associations will have to be made at that time and this code will likely go bye bye. > > return 0; > + > +err_associate: > + vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, > + &matrix_mdev->iommu_notifier); > +err_iommu: > + vfio_unregister_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY, > + &matrix_mdev->group_notifier); > +err_group: > + module_put(THIS_MODULE); > + return ret; > } > > static void vfio_ap_mdev_release(struct mdev_device *mdev) > @@ -985,6 +1034,9 @@ static void vfio_ap_mdev_release(struct mdev_device *mdev) > vfio_ap_mdev_reset_queues(mdev); > vfio_unregister_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY, > &matrix_mdev->group_notifier); > + vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, > + &matrix_mdev->iommu_notifier); > + vfio_ap_dissociate_queues(matrix_mdev); I think the matrix_mdev should be dissociated from queues when an adapter or domain is unassigned from the mdev device via its sysfs interfaces. I say this because unassigning an adapter or domain from an mdev device effectively takes away ownership of any AP queues removed from the mdev device's AP matrix as a result of the unassignment. It only makes sense to remove ownership from the vfio_ap_queue objects representing the queues at that time. This will become necessary for the forthcoming dynamic configuration patches. If an adapter or domain is dynamically unassigned while a guest is using the affected queues, then the dissociation will have to be made at that time and this code will likely go bye bye. > matrix_mdev->kvm = NULL; > module_put(THIS_MODULE); > } > diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h > index 10bc8b5..2781720 100644 > --- a/drivers/s390/crypto/vfio_ap_private.h > +++ b/drivers/s390/crypto/vfio_ap_private.h > @@ -80,7 +80,9 @@ struct ap_matrix_mdev { > struct list_head node; > struct ap_matrix matrix; > struct notifier_block group_notifier; > + struct notifier_block iommu_notifier; > struct kvm *kvm; > + struct mdev_device *mdev; > }; > > extern int vfio_ap_mdev_register(void); >