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 40E1AC10F14 for ; Tue, 23 Apr 2019 12:46:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 07C5E206A3 for ; Tue, 23 Apr 2019 12:46:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727734AbfDWMqv (ORCPT ); Tue, 23 Apr 2019 08:46:51 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:55522 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726033AbfDWMqv (ORCPT ); Tue, 23 Apr 2019 08:46:51 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x3NCdsVE109633 for ; Tue, 23 Apr 2019 08:46:49 -0400 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0b-001b2d01.pphosted.com with ESMTP id 2s22ev1knf-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 23 Apr 2019 08:46:48 -0400 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, 23 Apr 2019 13:46:44 +0100 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x3NCkhBg23593066 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 23 Apr 2019 12:46:43 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0EF8FA4060; Tue, 23 Apr 2019 12:46:43 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7594CA405B; Tue, 23 Apr 2019 12:46:42 +0000 (GMT) Received: from [9.145.50.246] (unknown [9.145.50.246]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 23 Apr 2019 12:46:42 +0000 (GMT) Reply-To: pmorel@linux.ibm.com Subject: Re: [PATCH v2 3/8] s390: vfio-ap: allow assignment of unavailable AP resources to mdev device To: Tony Krowiak , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: freude@linux.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.com, frankja@linux.ibm.com, david@redhat.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, pasic@linux.ibm.com, alex.williamson@redhat.com, kwankhede@nvidia.com References: <1555796980-27920-1-git-send-email-akrowiak@linux.ibm.com> <1555796980-27920-4-git-send-email-akrowiak@linux.ibm.com> From: Pierre Morel Date: Tue, 23 Apr 2019 14:46:42 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <1555796980-27920-4-git-send-email-akrowiak@linux.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 19042312-0028-0000-0000-00000363B7AD X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19042312-0029-0000-0000-0000242305B4 Message-Id: <2c76d792-00aa-a334-2243-b0f8b91295b2@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-04-23_03:,, 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-1904230088 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/04/2019 23:49, Tony Krowiak wrote: > The AP architecture does not preclude assignment of AP resources that are > not yet in the AP configuration (i.e., not available or not online). > Let's go ahead and implement this facet of the AP architecture for linux > guests. > > Access to AP resources is controlled by bit masks in a guest's SIE > state description (i.e., the control block containing the state of a > guest). When an AP instruction is executed on the guest, the firmware > combines the masks from the guest's SIE state description with the masks > from the host by doing a logical bitwise AND of the masks to create what > are defined as effective masks. The effective masks determine which AP > resources can be accessed by the guest. > > Effective masking allows the assignment of AP resources to a guest even > if the underlying device is not in the AP configuration. If the device > subsequently becomes configured, the guest will automatically have access > to the associated AP resources (e.g., AP queues). > > The current implementation does not allow assignment of AP resources to > an mdev device if the AP queues identified by the assignment are not > bound to the vfio_ap device driver. This patch allows assignment of AP > resources to the mdev device even if the AP queues are not bound to the > vfio_ap device driver, as long as the AP queues are not reserved by the > AP BUS for use by the zcrypt device drivers. If the queues are subsequently > bound to the vfio_ap device driver while a running guest is using the mdev > device, the guest will automatically gain access to the queues. Effective > masking prevents access to queues until such time as they become available. > > Signed-off-by: Tony Krowiak > --- > drivers/s390/crypto/vfio_ap_ops.c | 160 +++++--------------------------------- > 1 file changed, 18 insertions(+), 142 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index eae4ee24460a..221491a9ba95 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -113,122 +113,6 @@ static struct attribute_group *vfio_ap_mdev_type_groups[] = { > NULL, > }; > > -struct vfio_ap_queue_reserved { > - unsigned long *apid; > - unsigned long *apqi; > - bool reserved; > -}; > - > -/** > - * vfio_ap_has_queue > - * > - * @dev: an AP queue device > - * @data: a struct vfio_ap_queue_reserved reference > - * > - * Flags whether the AP queue device (@dev) has a queue ID containing the APQN, > - * apid or apqi specified in @data: > - * > - * - If @data contains both an apid and apqi value, then @data will be flagged > - * as reserved if the APID and APQI fields for the AP queue device matches > - * > - * - If @data contains only an apid value, @data will be flagged as > - * reserved if the APID field in the AP queue device matches > - * > - * - If @data contains only an apqi value, @data will be flagged as > - * reserved if the APQI field in the AP queue device matches > - * > - * Returns 0 to indicate the input to function succeeded. Returns -EINVAL if > - * @data does not contain either an apid or apqi. > - */ > -static int vfio_ap_has_queue(struct device *dev, void *data) > -{ > - struct vfio_ap_queue_reserved *qres = data; > - struct ap_queue *ap_queue = to_ap_queue(dev); > - ap_qid_t qid; > - unsigned long id; > - > - if (qres->apid && qres->apqi) { > - qid = AP_MKQID(*qres->apid, *qres->apqi); > - if (qid == ap_queue->qid) > - qres->reserved = true; > - } else if (qres->apid && !qres->apqi) { > - id = AP_QID_CARD(ap_queue->qid); > - if (id == *qres->apid) > - qres->reserved = true; > - } else if (!qres->apid && qres->apqi) { > - id = AP_QID_QUEUE(ap_queue->qid); > - if (id == *qres->apqi) > - qres->reserved = true; > - } else { > - return -EINVAL; > - } > - > - return 0; > -} > - > -/** > - * vfio_ap_verify_queue_reserved > - * > - * @matrix_dev: a mediated matrix device > - * @apid: an AP adapter ID > - * @apqi: an AP queue index > - * > - * Verifies that the AP queue with @apid/@apqi is reserved by the VFIO AP device > - * driver according to the following rules: > - * > - * - If both @apid and @apqi are not NULL, then there must be an AP queue > - * device bound to the vfio_ap driver with the APQN identified by @apid and > - * @apqi > - * > - * - If only @apid is not NULL, then there must be an AP queue device bound > - * to the vfio_ap driver with an APQN containing @apid > - * > - * - If only @apqi is not NULL, then there must be an AP queue device bound > - * to the vfio_ap driver with an APQN containing @apqi > - * > - * Returns 0 if the AP queue is reserved; otherwise, returns -EADDRNOTAVAIL. > - */ > -static int vfio_ap_verify_queue_reserved(unsigned long *apid, > - unsigned long *apqi) > -{ > - int ret; > - struct vfio_ap_queue_reserved qres; > - > - qres.apid = apid; > - qres.apqi = apqi; > - qres.reserved = false; > - > - ret = driver_for_each_device(&matrix_dev->vfio_ap_drv->driver, NULL, > - &qres, vfio_ap_has_queue); > - if (ret) > - return ret; > - > - if (qres.reserved) > - return 0; > - > - return -EADDRNOTAVAIL; > -} > - > -static int > -vfio_ap_mdev_verify_queues_reserved_for_apid(struct ap_matrix_mdev *matrix_mdev, > - unsigned long apid) You suppress this function but it is still in use in assign_adapter_store... > -{ > - int ret; > - unsigned long apqi; > - unsigned long nbits = matrix_mdev->matrix.aqm_max + 1; > - > - if (find_first_bit_inv(matrix_mdev->matrix.aqm, nbits) >= nbits) > - return vfio_ap_verify_queue_reserved(&apid, NULL); > - > - for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, nbits) { > - ret = vfio_ap_verify_queue_reserved(&apid, &apqi); > - if (ret) > - return ret; > - } > - > - return 0; > -} > - > /** > * vfio_ap_mdev_verify_no_sharing > * > @@ -359,9 +243,17 @@ static ssize_t assign_adapter_store(struct device *dev, > > set_bit_inv(apid, matrix_mdev->matrix.apm); > > + ret = ap_apqn_in_matrix_owned_by_def_drv(matrix_mdev->matrix.apm, > + matrix_mdev->matrix.aqm); > + > + /* If any APQN is owned by a default driver */ > + ret = (ret == 1) ? -EADDRNOTAVAIL : ret; > + if (ret) > + goto error; > + > ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev); > if (ret) > - goto share_err; > + goto error; > > if (matrix_mdev->shadow_crycb) > set_bit_inv(apid, matrix_mdev->shadow_crycb->apm); > @@ -369,7 +261,7 @@ static ssize_t assign_adapter_store(struct device *dev, > ret = count; > goto done; > > -share_err: > +error: > clear_bit_inv(apid, matrix_mdev->matrix.apm); > done: > mutex_unlock(&matrix_dev->lock); > @@ -426,26 +318,6 @@ static ssize_t unassign_adapter_store(struct device *dev, > } > static DEVICE_ATTR_WO(unassign_adapter); > > -static int > -vfio_ap_mdev_verify_queues_reserved_for_apqi(struct ap_matrix_mdev *matrix_mdev, > - unsigned long apqi) > -{ > - int ret; > - unsigned long apid; > - unsigned long nbits = matrix_mdev->matrix.apm_max + 1; > - > - if (find_first_bit_inv(matrix_mdev->matrix.apm, nbits) >= nbits) > - return vfio_ap_verify_queue_reserved(NULL, &apqi); > - > - for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, nbits) { > - ret = vfio_ap_verify_queue_reserved(&apid, &apqi); > - if (ret) > - return ret; > - } > - > - return 0; > -} > - > /** > * assign_domain_store > * > @@ -500,12 +372,16 @@ static ssize_t assign_domain_store(struct device *dev, > > mutex_lock(&matrix_dev->lock); > > - ret = vfio_ap_mdev_verify_queues_reserved_for_apqi(matrix_mdev, apqi); > - if (ret) > - goto done; > - > set_bit_inv(apqi, matrix_mdev->matrix.aqm); > > + ret = ap_apqn_in_matrix_owned_by_def_drv(matrix_mdev->matrix.apm, > + matrix_mdev->matrix.aqm); > + > + /* If any APQN is owned by a default driver */ > + ret = (ret == 1) ? -EADDRNOTAVAIL : ret; > + if (ret) > + goto error; forget to add the error label ? > + > ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev); > if (ret) > goto share_err; > -- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany