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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 E6962C56202 for ; Thu, 26 Nov 2020 08:50:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9B2A1208CA for ; Thu, 26 Nov 2020 08:50:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389013AbgKZIuT (ORCPT ); Thu, 26 Nov 2020 03:50:19 -0500 Received: from mga02.intel.com ([134.134.136.20]:61887 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726392AbgKZIuT (ORCPT ); Thu, 26 Nov 2020 03:50:19 -0500 IronPort-SDR: MzFXFOSU0FJi6aO7yXxvR74dBrECbzGlNmrYYR7uhFQmXLkQBdTd94EXJGqQ7N3j4ymIkpZpBH YRAsBBVS8wKA== X-IronPort-AV: E=McAfee;i="6000,8403,9816"; a="159304162" X-IronPort-AV: E=Sophos;i="5.78,371,1599548400"; d="scan'208";a="159304162" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Nov 2020 00:50:18 -0800 IronPort-SDR: 0ckRKnhBtLlrKe8kX3O58++wCeYNqa8uzQDWFbhBPT0Es9yZXN3LFAFJos4EYK1zxawGWUpSYN dybkCpwIi6Fg== X-IronPort-AV: E=Sophos;i="5.78,371,1599548400"; d="scan'208";a="547637576" Received: from blu2-mobl3.ccr.corp.intel.com (HELO [10.254.208.39]) ([10.254.208.39]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Nov 2020 00:50:15 -0800 Cc: baolu.lu@linux.intel.com, Joerg Roedel , Will Deacon , Robin Murphy , Jean-Philippe Brucker , "Tian, Kevin" , "Raj, Ashok" , "Jiang, Dave" , "Zeng, Xin" , "iommu@lists.linux-foundation.org" , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" Subject: Re: [PATCH v2 1/1] vfio/type1: Add vfio_group_domain() To: "Liu, Yi L" , Alex Williamson , Cornelia Huck References: <20201126012726.1185171-1-baolu.lu@linux.intel.com> From: Lu Baolu Message-ID: Date: Thu, 26 Nov 2020 16:50:13 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi Yi, On 2020/11/26 15:21, Liu, Yi L wrote: > On Thurs, Nov 26, 2020, at 9:27 AM, Lu Baolu wrote: >> Add the API for getting the domain from a vfio group. This could be used >> by the physical device drivers which rely on the vfio/mdev framework for >> mediated device user level access. The typical use case like below: >> >> unsigned int pasid; >> struct vfio_group *vfio_group; >> struct iommu_domain *iommu_domain; >> struct device *dev = mdev_dev(mdev); >> struct device *iommu_device = mdev_get_iommu_device(dev); >> >> if (!iommu_device || >> !iommu_dev_feature_enabled(iommu_device, IOMMU_DEV_FEAT_AUX)) >> return -EINVAL; >> >> vfio_group = vfio_group_get_external_user_from_dev(dev);(dev); > > duplicate (dev); 😊other parts looks good to me. perhaps, you can also Will fix this typo. Thanks! > describe that the release function of a sub-device fd should also call > vfio_group_put_external_user() to release its reference on the vfio_group. This is just a sample code. The callers are free to decide when to get and release the vfio_group. > > Regards, > Yi Liu Best regards, baolu > >> if (IS_ERR_OR_NULL(vfio_group)) >> return -EFAULT; >> >> iommu_domain = vfio_group_domain(vfio_group); >> if (IS_ERR_OR_NULL(iommu_domain)) { >> vfio_group_put_external_user(vfio_group); >> return -EFAULT; >> } >> >> pasid = iommu_aux_get_pasid(iommu_domain, iommu_device); >> if (pasid < 0) { >> vfio_group_put_external_user(vfio_group); >> return -EFAULT; >> } >> >> /* Program device context with pasid value. */ >> ... >> >> Signed-off-by: Lu Baolu >> --- >> drivers/vfio/vfio.c | 18 ++++++++++++++++++ >> drivers/vfio/vfio_iommu_type1.c | 23 +++++++++++++++++++++++ >> include/linux/vfio.h | 3 +++ >> 3 files changed, 44 insertions(+) >> >> Change log: >> - v1: https://lore.kernel.org/linux-iommu/20201112022407.2063896-1-baolu.lu@linux.intel.com/ >> - Changed according to comments @ https://lore.kernel.org/linux-iommu/20201116125631.2d043fcd@w520.home/ >> >> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c >> index 2151bc7f87ab..62c652111c88 100644 >> --- a/drivers/vfio/vfio.c >> +++ b/drivers/vfio/vfio.c >> @@ -2331,6 +2331,24 @@ int vfio_unregister_notifier(struct device *dev, >> enum vfio_notify_type type, >> } >> EXPORT_SYMBOL(vfio_unregister_notifier); >> >> +struct iommu_domain *vfio_group_domain(struct vfio_group *group) >> +{ >> + struct vfio_container *container; >> + struct vfio_iommu_driver *driver; >> + >> + if (!group) >> + return ERR_PTR(-EINVAL); >> + >> + container = group->container; >> + driver = container->iommu_driver; >> + if (likely(driver && driver->ops->group_domain)) >> + return driver->ops->group_domain(container->iommu_data, >> + group->iommu_group); >> + else >> + return ERR_PTR(-ENOTTY); >> +} >> +EXPORT_SYMBOL(vfio_group_domain); >> + >> /** >> * Module/class support >> */ >> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c >> index 67e827638995..783f18f21b95 100644 >> --- a/drivers/vfio/vfio_iommu_type1.c >> +++ b/drivers/vfio/vfio_iommu_type1.c >> @@ -2980,6 +2980,28 @@ static int vfio_iommu_type1_dma_rw(void *iommu_data, >> dma_addr_t user_iova, >> return ret; >> } >> >> +static void *vfio_iommu_type1_group_domain(void *iommu_data, >> + struct iommu_group *iommu_group) >> +{ >> + struct vfio_iommu *iommu = iommu_data; >> + struct iommu_domain *domain = NULL; >> + struct vfio_domain *d; >> + >> + if (!iommu || !iommu_group) >> + return ERR_PTR(-EINVAL); >> + >> + mutex_lock(&iommu->lock); >> + list_for_each_entry(d, &iommu->domain_list, next) { >> + if (find_iommu_group(d, iommu_group)) { >> + domain = d->domain; >> + break; >> + } >> + } >> + mutex_unlock(&iommu->lock); >> + >> + return domain; >> +} >> + >> static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = { >> .name = "vfio-iommu-type1", >> .owner = THIS_MODULE, >> @@ -2993,6 +3015,7 @@ static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = { >> .register_notifier = vfio_iommu_type1_register_notifier, >> .unregister_notifier = vfio_iommu_type1_unregister_notifier, >> .dma_rw = vfio_iommu_type1_dma_rw, >> + .group_domain = vfio_iommu_type1_group_domain, >> }; >> >> static int __init vfio_iommu_type1_init(void) >> diff --git a/include/linux/vfio.h b/include/linux/vfio.h >> index 38d3c6a8dc7e..a0613a6f21cc 100644 >> --- a/include/linux/vfio.h >> +++ b/include/linux/vfio.h >> @@ -90,6 +90,7 @@ struct vfio_iommu_driver_ops { >> struct notifier_block *nb); >> int (*dma_rw)(void *iommu_data, dma_addr_t user_iova, >> void *data, size_t count, bool write); >> + void *(*group_domain)(void *iommu_data, struct iommu_group *group); >> }; >> >> extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops); >> @@ -126,6 +127,8 @@ extern int vfio_group_unpin_pages(struct vfio_group *group, >> extern int vfio_dma_rw(struct vfio_group *group, dma_addr_t user_iova, >> void *data, size_t len, bool write); >> >> +extern struct iommu_domain *vfio_group_domain(struct vfio_group *group); >> + >> /* each type has independent events */ >> enum vfio_notify_type { >> VFIO_IOMMU_NOTIFY = 0, >> -- >> 2.25.1 >