From patchwork Mon Oct 5 20:37:50 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Williamson X-Patchwork-Id: 526550 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 1B47314012C for ; Tue, 6 Oct 2015 07:41:53 +1100 (AEDT) Received: from localhost ([::1]:47657 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZjCZy-0003pI-N3 for incoming@patchwork.ozlabs.org; Mon, 05 Oct 2015 16:41:50 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39764) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZjCWA-0005hU-L0 for qemu-devel@nongnu.org; Mon, 05 Oct 2015 16:37:55 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZjCW7-0001ke-Et for qemu-devel@nongnu.org; Mon, 05 Oct 2015 16:37:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50544) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZjCW7-0001kF-8y for qemu-devel@nongnu.org; Mon, 05 Oct 2015 16:37:51 -0400 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id E080391E87; Mon, 5 Oct 2015 20:37:50 +0000 (UTC) Received: from gimli.home (ovpn-113-42.phx2.redhat.com [10.3.113.42]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t95KboMU022171; Mon, 5 Oct 2015 16:37:50 -0400 From: Alex Williamson To: qemu-devel@nongnu.org Date: Mon, 05 Oct 2015 14:37:50 -0600 Message-ID: <20151005203748.310.35820.stgit@gimli.home> In-Reply-To: <20151005203357.310.44414.stgit@gimli.home> References: <20151005203357.310.44414.stgit@gimli.home> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: David Gibson Subject: [Qemu-devel] [PULL 09/10] vfio: Allow hotplug of containers onto existing guest IOMMU mappings X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: David Gibson At present the memory listener used by vfio to keep host IOMMU mappings in sync with the guest memory image assumes that if a guest IOMMU appears, then it has no existing mappings. This may not be true if a VFIO device is hotplugged onto a guest bus which didn't previously include a VFIO device, and which has existing guest IOMMU mappings. Therefore, use the memory_region_register_iommu_notifier_replay() function in order to fix this case, replaying existing guest IOMMU mappings, bringing the host IOMMU into sync with the guest IOMMU. Signed-off-by: David Gibson Signed-off-by: Alex Williamson --- hw/vfio/common.c | 23 +++++++++-------------- 1 file changed, 9 insertions(+), 14 deletions(-) diff --git a/hw/vfio/common.c b/hw/vfio/common.c index f666de2..6797208 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -312,6 +312,11 @@ out: rcu_read_unlock(); } +static hwaddr vfio_container_granularity(VFIOContainer *container) +{ + return (hwaddr)1 << ctz64(container->iova_pgsizes); +} + static void vfio_listener_region_add(MemoryListener *listener, MemoryRegionSection *section) { @@ -369,26 +374,16 @@ static void vfio_listener_region_add(MemoryListener *listener, * would be the right place to wire that up (tell the KVM * device emulation the VFIO iommu handles to use). */ - /* - * This assumes that the guest IOMMU is empty of - * mappings at this point. - * - * One way of doing this is: - * 1. Avoid sharing IOMMUs between emulated devices or different - * IOMMU groups. - * 2. Implement VFIO_IOMMU_ENABLE in the host kernel to fail if - * there are some mappings in IOMMU. - * - * VFIO on SPAPR does that. Other IOMMU models may do that different, - * they must make sure there are no existing mappings or - * loop through existing mappings to map them into VFIO. - */ giommu = g_malloc0(sizeof(*giommu)); giommu->iommu = section->mr; giommu->container = container; giommu->n.notify = vfio_iommu_map_notify; QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next); + memory_region_register_iommu_notifier(giommu->iommu, &giommu->n); + memory_region_iommu_replay(giommu->iommu, &giommu->n, + vfio_container_granularity(container), + false); return; }