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,URIBL_BLOCKED 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 A9FDEC10F00 for ; Wed, 27 Mar 2019 18:55:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7543C205C9 for ; Wed, 27 Mar 2019 18:55:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390080AbfC0SQd (ORCPT ); Wed, 27 Mar 2019 14:16:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42244 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389751AbfC0SQ3 (ORCPT ); Wed, 27 Mar 2019 14:16:29 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 907133087BCC; Wed, 27 Mar 2019 18:16:27 +0000 (UTC) Received: from x1.home (ovpn-116-99.phx2.redhat.com [10.3.116.99]) by smtp.corp.redhat.com (Postfix) with ESMTP id BFBFE82B84; Wed, 27 Mar 2019 18:16:25 +0000 (UTC) Date: Wed, 27 Mar 2019 12:16:25 -0600 From: Alex Williamson To: Parav Pandit Cc: Kirti Wankhede , Lu Baolu , Joerg Roedel , David Woodhouse , "ashok.raj@intel.com" , "sanjay.k.kumar@intel.com" , "jacob.jun.pan@intel.com" , "kevin.tian@intel.com" , Jean-Philippe Brucker , "yi.l.liu@intel.com" , "yi.y.sun@intel.com" , "peterx@redhat.com" , "tiwei.bie@intel.com" , "xin.zeng@intel.com" , "iommu@lists.linux-foundation.org" , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Jacob Pan , Neo Jia Subject: Re: [PATCH v8 7/9] vfio/mdev: Add iommu related member in mdev_device Message-ID: <20190327121625.4a8db805@x1.home> In-Reply-To: References: <20190325013036.18400-1-baolu.lu@linux.intel.com> <20190325013036.18400-8-baolu.lu@linux.intel.com> Organization: Red Hat MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Wed, 27 Mar 2019 18:16:27 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 27 Mar 2019 14:17:57 +0000 Parav Pandit wrote: > > -----Original Message----- > > From: linux-kernel-owner@vger.kernel.org > owner@vger.kernel.org> On Behalf Of Kirti Wankhede > > Sent: Tuesday, March 26, 2019 4:33 AM > > To: Lu Baolu ; Joerg Roedel ; > > David Woodhouse ; Alex Williamson > > > > Cc: ashok.raj@intel.com; sanjay.k.kumar@intel.com; > > jacob.jun.pan@intel.com; kevin.tian@intel.com; Jean-Philippe Brucker > philippe.brucker@arm.com>; yi.l.liu@intel.com; yi.y.sun@intel.com; > > peterx@redhat.com; tiwei.bie@intel.com; xin.zeng@intel.com; > > iommu@lists.linux-foundation.org; kvm@vger.kernel.org; linux- > > kernel@vger.kernel.org; Jacob Pan ; Neo Jia > > > > Subject: Re: [PATCH v8 7/9] vfio/mdev: Add iommu related member in > > mdev_device > > > > > > > > On 3/25/2019 7:00 AM, Lu Baolu wrote: > > > A parent device might create different types of mediated devices. For > > > example, a mediated device could be created by the parent device with > > > full isolation and protection provided by the IOMMU. One usage case > > > could be found on Intel platforms where a mediated device is an > > > assignable subset of a PCI, the DMA requests on behalf of it are all > > > tagged with a PASID. Since IOMMU supports PASID-granular translations > > > (scalable mode in VT-d 3.0), this mediated device could be > > > individually protected and isolated by an IOMMU. > > > > > > This patch adds a new member in the struct mdev_device to indicate > > > that the mediated device represented by mdev could be isolated and > > > protected by attaching a domain to a device represented by > > > mdev->iommu_device. It also adds a helper to add or set the iommu > > > device. > > > > > > * mdev_device->iommu_device > > > - This, if set, indicates that the mediated device could > > > be fully isolated and protected by IOMMU via attaching > > > an iommu domain to this device. If empty, it indicates > > > using vendor defined isolation, hence bypass IOMMU. > > > > > > * mdev_set/get_iommu_device(dev, iommu_device) > > > - Set or get the iommu device which represents this mdev > > > in IOMMU's device scope. Drivers don't need to set the > > > iommu device if it uses vendor defined isolation. > > > > > > Cc: Ashok Raj > > > Cc: Jacob Pan > > > Cc: Kevin Tian > > > Cc: Liu Yi L > > > Suggested-by: Kevin Tian > > > Suggested-by: Alex Williamson > > > Signed-off-by: Lu Baolu > > > Reviewed-by: Jean-Philippe Brucker > > > --- > > > drivers/vfio/mdev/mdev_core.c | 18 ++++++++++++++++++ > > > drivers/vfio/mdev/mdev_private.h | 1 + > > > include/linux/mdev.h | 14 ++++++++++++++ > > > 3 files changed, 33 insertions(+) > > > > > > diff --git a/drivers/vfio/mdev/mdev_core.c > > > b/drivers/vfio/mdev/mdev_core.c index b96fedc77ee5..1b6435529166 > > > 100644 > > > --- a/drivers/vfio/mdev/mdev_core.c > > > +++ b/drivers/vfio/mdev/mdev_core.c > > > @@ -390,6 +390,24 @@ int mdev_device_remove(struct device *dev, bool > > force_remove) > > > return 0; > > > } > > > > > > +int mdev_set_iommu_device(struct device *dev, struct device > > > +*iommu_device) { > > > + struct mdev_device *mdev = to_mdev_device(dev); > > > + > > > + mdev->iommu_device = iommu_device; > > > + > > > + return 0; > > > +} > > > +EXPORT_SYMBOL(mdev_set_iommu_device); > > > + > > > +struct device *mdev_get_iommu_device(struct device *dev) { > > > + struct mdev_device *mdev = to_mdev_device(dev); > > > + > > > + return mdev->iommu_device; > > > +} > > > +EXPORT_SYMBOL(mdev_get_iommu_device); > > > + > > > static int __init mdev_init(void) > > > { > > > return mdev_bus_register(); > > > diff --git a/drivers/vfio/mdev/mdev_private.h > > > b/drivers/vfio/mdev/mdev_private.h > > > index 379758c52b1b..bfb7b22a7cb6 100644 > > > --- a/drivers/vfio/mdev/mdev_private.h > > > +++ b/drivers/vfio/mdev/mdev_private.h > > > @@ -34,6 +34,7 @@ struct mdev_device { > > > struct list_head next; > > > struct kobject *type_kobj; > > > bool active; > > > + struct device *iommu_device; > > > }; > > > > This is not a performance path, but it is a good practice to create naturally aligned/packed structures. > You should define struct device *iommu_device; before bool active. Agreed, if someone wants to fixup before commit or if there's another spin please do so, otherwise we can adjust it in a trivial follow-up patch. Thanks, Alex