From patchwork Thu Jan 12 07:19:42 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dong Jia Shi X-Patchwork-Id: 9512215 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 06D57601E7 for ; Thu, 12 Jan 2017 07:20:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ED998285ED for ; Thu, 12 Jan 2017 07:20:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E24E42861D; Thu, 12 Jan 2017 07:20:38 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7D2AE285ED for ; Thu, 12 Jan 2017 07:20:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750884AbdALHUh (ORCPT ); Thu, 12 Jan 2017 02:20:37 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:60734 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750843AbdALHUf (ORCPT ); Thu, 12 Jan 2017 02:20:35 -0500 Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id v0C7IrsF141176 for ; Thu, 12 Jan 2017 02:20:35 -0500 Received: from e38.co.us.ibm.com (e38.co.us.ibm.com [32.97.110.159]) by mx0a-001b2d01.pphosted.com with ESMTP id 27x2q5msq3-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 12 Jan 2017 02:20:35 -0500 Received: from localhost by e38.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Thu, 12 Jan 2017 00:20:32 -0700 Received: from b03cxnp08028.gho.boulder.ibm.com (b03cxnp08028.gho.boulder.ibm.com [9.17.130.20]) by d03dlp01.boulder.ibm.com (Postfix) with ESMTP id 6D8D91FF0021; Thu, 12 Jan 2017 00:20:10 -0700 (MST) Received: from b03ledav001.gho.boulder.ibm.com (b03ledav001.gho.boulder.ibm.com [9.17.130.232]) by b03cxnp08028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v0C7KUDs7209458; Thu, 12 Jan 2017 00:20:30 -0700 Received: from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7C03B6E03D; Thu, 12 Jan 2017 00:20:30 -0700 (MST) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by b03ledav001.gho.boulder.ibm.com (Postfix) with ESMTP id 4F7376E038; Thu, 12 Jan 2017 00:20:28 -0700 (MST) From: Dong Jia Shi To: kvm@vger.kernel.org, linux-s390@vger.kernel.org, qemu-devel@nongnu.org Cc: bjsdjshi@linux.vnet.ibm.com, renxiaof@linux.vnet.ibm.com, cornelia.huck@de.ibm.com, borntraeger@de.ibm.com, agraf@suse.com, alex.williamson@redhat.com, pmorel@linux.vnet.ibm.com, pasic@linux.vnet.ibm.com, wkywang@linux.vnet.ibm.com Subject: [PATCH RFC v2 10/15] vfio: ccw: realize VFIO_DEVICE_RESET ioctl Date: Thu, 12 Jan 2017 08:19:42 +0100 X-Mailer: git-send-email 2.8.4 In-Reply-To: <20170112071947.98071-1-bjsdjshi@linux.vnet.ibm.com> References: <20170112071947.98071-1-bjsdjshi@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 17011207-0028-0000-0000-0000066EE984 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00006418; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000199; SDB=6.00806504; UDB=6.00392482; IPR=6.00583835; BA=6.00005049; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00013900; XFM=3.00000011; UTC=2017-01-12 07:20:34 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17011207-0029-0000-0000-000032516752 Message-Id: <20170112071947.98071-11-bjsdjshi@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-01-12_04:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=2 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1612050000 definitions=main-1701120098 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Introduce VFIO_DEVICE_RESET ioctl for vfio-ccw to make it possible to hot-reset the device. We try to achieve a reset by first disabling the subchannel and then enabling it again: this should clear all state at the subchannel. Signed-off-by: Dong Jia Shi --- drivers/s390/cio/vfio_ccw_ops.c | 42 +++++++++++++++++++++++++++++------------ 1 file changed, 30 insertions(+), 12 deletions(-) diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c index 5c60cda..b702735 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -19,6 +19,31 @@ #define MAX_INSTANCES 1 static int available_instances = MAX_INSTANCES; +static int vfio_ccw_mdev_reset(struct mdev_device *mdev) +{ + struct vfio_ccw_private *private = dev_get_drvdata(mdev->dev.parent); + struct subchannel *sch; + int ret; + + if (!private) + return -ENODEV; + + sch = private->sch; + /* + * TODO: + * In the cureent stage, some things like "no I/O running" and "no + * interrupt pending" are clear, but we are not sure what other state + * we need to care about. + * There are still a lot more instructions need to be handled. We + * should come back here later. + */ + ret = vfio_ccw_sch_quiesce(sch); + if (ret) + return ret; + + return cio_enable_subchannel(sch, (u32)(unsigned long)sch); +} + static int vfio_ccw_mdev_notifier(struct notifier_block *nb, unsigned long action, void *data) @@ -35,15 +60,11 @@ static int vfio_ccw_mdev_notifier(struct notifier_block *nb, */ if (action == VFIO_IOMMU_NOTIFY_DMA_UNMAP) { struct vfio_iommu_type1_dma_unmap *unmap = data; - struct subchannel *sch = private->sch; if (!cp_iova_pinned(&private->cp, unmap->iova)) return NOTIFY_OK; - if (vfio_ccw_sch_quiesce(sch)) - return NOTIFY_BAD; - - if (cio_enable_subchannel(sch, (u32)(unsigned long)sch)) + if (vfio_ccw_mdev_reset(private->mdev)) return NOTIFY_BAD; cp_free(&private->cp); @@ -107,14 +128,9 @@ static int vfio_ccw_mdev_create(struct kobject *kobj, struct mdev_device *mdev) static int vfio_ccw_mdev_remove(struct mdev_device *mdev) { struct vfio_ccw_private *private = dev_get_drvdata(mdev->parent->dev); - struct subchannel *sch; int ret; - sch = private->sch; - ret = vfio_ccw_sch_quiesce(sch); - if (ret) - return ret; - ret = cio_enable_subchannel(sch, (u32)(unsigned long)sch); + ret = vfio_ccw_mdev_reset(mdev); if (ret) return ret; @@ -193,7 +209,7 @@ static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev, static int vfio_ccw_mdev_get_device_info(struct mdev_device *mdev, struct vfio_device_info *info) { - info->flags = VFIO_DEVICE_FLAGS_CCW; + info->flags = VFIO_DEVICE_FLAGS_CCW | VFIO_DEVICE_FLAGS_RESET; info->num_regions = VFIO_CCW_NUM_REGIONS; info->num_irqs = 0; @@ -265,6 +281,8 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev, return copy_to_user((void __user *)arg, &info, minsz); } + case VFIO_DEVICE_RESET: + return vfio_ccw_mdev_reset(mdev); default: return -ENOTTY; }