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=-11.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 5E0FCC433E1 for ; Tue, 14 Jul 2020 16:32:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 427DD22475 for ; Tue, 14 Jul 2020 16:32:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728001AbgGNQcu (ORCPT ); Tue, 14 Jul 2020 12:32:50 -0400 Received: from mga03.intel.com ([134.134.136.65]:63516 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726062AbgGNQct (ORCPT ); Tue, 14 Jul 2020 12:32:49 -0400 IronPort-SDR: TBhSCOYiAfpQiyktt+PWuzmEWTFArAYRyBIgxuMsJCl6PciaDARBnS/FRbJYuLsHGFHmbGcJfQ myKhi0rwQ0ww== X-IronPort-AV: E=McAfee;i="6000,8403,9681"; a="148957026" X-IronPort-AV: E=Sophos;i="5.75,352,1589266800"; d="scan'208";a="148957026" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2020 09:32:48 -0700 IronPort-SDR: VIIs1ZhnFb2/oR+R9r078i98dlsTEFvH/PoGIlyJf5/fUblIkEDHEi6vJ4Rx8zhuKXqvbKt5+I Cscr8DBfInkQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,352,1589266800"; d="scan'208";a="317775607" Received: from jacob-builder.jf.intel.com (HELO jacob-builder) ([10.7.199.155]) by fmsmga002.fm.intel.com with ESMTP; 14 Jul 2020 09:32:47 -0700 Date: Tue, 14 Jul 2020 09:39:09 -0700 From: Jacob Pan To: Lu Baolu Cc: Joerg Roedel , Alex Williamson , Jean-Philippe Brucker , Kevin Tian , Dave Jiang , Ashok Raj , kvm@vger.kernel.org, Cornelia Huck , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, Robin Murphy , jacob.jun.pan@linux.intel.com Subject: Re: [PATCH v3 2/4] iommu: Add iommu_aux_at(de)tach_group() Message-ID: <20200714093909.1ab93c9e@jacob-builder> In-Reply-To: <20200714055703.5510-3-baolu.lu@linux.intel.com> References: <20200714055703.5510-1-baolu.lu@linux.intel.com> <20200714055703.5510-3-baolu.lu@linux.intel.com> Organization: OTC X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 14 Jul 2020 13:57:01 +0800 Lu Baolu wrote: > This adds two new aux-domain APIs for a use case like vfio/mdev where > sub-devices derived from an aux-domain capable device are created and > put in an iommu_group. > > /** > * iommu_aux_attach_group - attach an aux-domain to an iommu_group > which > * contains sub-devices (for example mdevs) > derived > * from @dev. > * @domain: an aux-domain; > * @group: an iommu_group which contains sub-devices derived from > @dev; > * @dev: the physical device which supports IOMMU_DEV_FEAT_AUX. > * > * Returns 0 on success, or an error value. > */ > int iommu_aux_attach_group(struct iommu_domain *domain, > struct iommu_group *group, > struct device *dev) > > /** > * iommu_aux_detach_group - detach an aux-domain from an iommu_group > * > * @domain: an aux-domain; > * @group: an iommu_group which contains sub-devices derived from > @dev; > * @dev: the physical device which supports IOMMU_DEV_FEAT_AUX. > * > * @domain must have been attached to @group via > iommu_aux_attach_group(). */ > void iommu_aux_detach_group(struct iommu_domain *domain, > struct iommu_group *group, > struct device *dev) > > It also adds a flag in the iommu_group data structure to identify > an iommu_group with aux-domain attached from those normal ones. > > Signed-off-by: Lu Baolu > --- > drivers/iommu/iommu.c | 58 > +++++++++++++++++++++++++++++++++++++++++++ include/linux/iommu.h | > 17 +++++++++++++ 2 files changed, 75 insertions(+) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index e1fdd3531d65..cad5a19ebf22 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -45,6 +45,7 @@ struct iommu_group { > struct iommu_domain *default_domain; > struct iommu_domain *domain; > struct list_head entry; > + unsigned int aux_domain_attached:1; > }; > > struct group_device { > @@ -2759,6 +2760,63 @@ int iommu_aux_get_pasid(struct iommu_domain > *domain, struct device *dev) } > EXPORT_SYMBOL_GPL(iommu_aux_get_pasid); > > +/** > + * iommu_aux_attach_group - attach an aux-domain to an iommu_group > which > + * contains sub-devices (for example mdevs) > derived > + * from @dev. > + * @domain: an aux-domain; > + * @group: an iommu_group which contains sub-devices derived from > @dev; > + * @dev: the physical device which supports IOMMU_DEV_FEAT_AUX. > + * > + * Returns 0 on success, or an error value. > + */ > +int iommu_aux_attach_group(struct iommu_domain *domain, > + struct iommu_group *group, struct device > *dev) +{ > + int ret = -EBUSY; > + > + mutex_lock(&group->mutex); > + if (group->domain) > + goto out_unlock; > + Perhaps I missed something but are we assuming only one mdev per mdev group? That seems to change the logic where vfio does: iommu_group_for_each_dev() iommu_aux_attach_device() > + ret = iommu_aux_attach_device(domain, dev); > + if (!ret) { > + group->domain = domain; > + group->aux_domain_attached = true; > + } > + > +out_unlock: > + mutex_unlock(&group->mutex); > + return ret; > +} > +EXPORT_SYMBOL_GPL(iommu_aux_attach_group); > + > +/** > + * iommu_aux_detach_group - detach an aux-domain from an iommu_group > + * > + * @domain: an aux-domain; > + * @group: an iommu_group which contains sub-devices derived from > @dev; > + * @dev: the physical device which supports IOMMU_DEV_FEAT_AUX. > + * > + * @domain must have been attached to @group via > iommu_aux_attach_group(). > + */ > +void iommu_aux_detach_group(struct iommu_domain *domain, > + struct iommu_group *group, struct device > *dev) +{ > + mutex_lock(&group->mutex); > + > + if (WARN_ON(!group->aux_domain_attached || group->domain != > domain)) > + goto out_unlock; > + > + iommu_aux_detach_device(domain, dev); > + group->aux_domain_attached = false; > + group->domain = NULL; > + > +out_unlock: > + mutex_unlock(&group->mutex); > +} > +EXPORT_SYMBOL_GPL(iommu_aux_detach_group); > + > /** > * iommu_sva_bind_device() - Bind a process address space to a device > * @dev: the device > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > index 5657d4fef9f2..9506551139ab 100644 > --- a/include/linux/iommu.h > +++ b/include/linux/iommu.h > @@ -635,6 +635,10 @@ bool iommu_dev_feature_enabled(struct device > *dev, enum iommu_dev_features f); int iommu_aux_attach_device(struct > iommu_domain *domain, struct device *dev); void > iommu_aux_detach_device(struct iommu_domain *domain, struct device > *dev); int iommu_aux_get_pasid(struct iommu_domain *domain, struct > device *dev); +int iommu_aux_attach_group(struct iommu_domain *domain, > + struct iommu_group *group, struct device > *dev); +void iommu_aux_detach_group(struct iommu_domain *domain, > + struct iommu_group *group, struct device > *dev); > struct iommu_sva *iommu_sva_bind_device(struct device *dev, > struct mm_struct *mm, > @@ -1023,6 +1027,19 @@ iommu_aux_get_pasid(struct iommu_domain > *domain, struct device *dev) return -ENODEV; > } > > +static inline int > +iommu_aux_attach_group(struct iommu_domain *domain, > + struct iommu_group *group, struct device *dev) > +{ > + return -ENODEV; > +} > + > +static inline void > +iommu_aux_detach_group(struct iommu_domain *domain, > + struct iommu_group *group, struct device *dev) > +{ > +} > + > static inline struct iommu_sva * > iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, void > *drvdata) { [Jacob Pan]