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 E00C7C43381 for ; Tue, 19 Feb 2019 19:04:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B335C20855 for ; Tue, 19 Feb 2019 19:04:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729422AbfBSTEd (ORCPT ); Tue, 19 Feb 2019 14:04:33 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:39348 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725939AbfBSTEc (ORCPT ); Tue, 19 Feb 2019 14:04:32 -0500 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1JImkle012408 for ; Tue, 19 Feb 2019 14:04:31 -0500 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0a-001b2d01.pphosted.com with ESMTP id 2qrpkwk8nq-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 19 Feb 2019 14:04:30 -0500 Received: from localhost by e06smtp07.uk.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) Tue, 19 Feb 2019 19:04:25 -0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x1JJ4OcL26869948 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 19 Feb 2019 19:04:24 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EF2B3AE053; Tue, 19 Feb 2019 19:04:23 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4DBBDAE045; Tue, 19 Feb 2019 19:04:23 +0000 (GMT) Received: from [9.145.49.77] (unknown [9.145.49.77]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 19 Feb 2019 19:04:23 +0000 (GMT) Reply-To: pmorel@linux.ibm.com Subject: Re: [PATCH v3 6/9] vfio: ap: register IOMMU VFIO notifier To: Halil Pasic , Tony Krowiak Cc: borntraeger@de.ibm.com, 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, 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> <3ce0a3a0-22fb-c418-321d-7e6e3af5b66c@linux.ibm.com> <20190219105946.29e510a6@oc2783563651> From: Pierre Morel Date: Tue, 19 Feb 2019 20:04:22 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <20190219105946.29e510a6@oc2783563651> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 19021919-0028-0000-0000-0000034A7F94 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19021919-0029-0000-0000-00002408BC89 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-19_12:,, 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-1902190134 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 19/02/2019 10:59, Halil Pasic wrote: > On Fri, 15 Feb 2019 17:55:35 -0500 > Tony Krowiak wrote: > >> 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 > > [..] > 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. >> > > > Actually, we need the stuff in vfio_ap_queues only if the guest is > offered to decides to use AP adaper interrupts. I would prefer to have > it around only when needed: as long as we have the nib pinned for any > given queue. Is there a reason why not to do so? > > Regards, > Halil > > [..] > Since I will rework the vfio_ap_queue life cycle, I will study this. But I find the creation / deletion in probe/remove and the link/unlimk to the matrix device in assign/un_assign as suggested by Tony more logical. Regards, Pierre -- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany