From patchwork Wed Jan 29 12:16:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yi Liu X-Patchwork-Id: 11356153 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 001D214E3 for ; Wed, 29 Jan 2020 12:24:09 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D553E2064C for ; Wed, 29 Jan 2020 12:24:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D553E2064C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:45562 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iwmO8-0003p5-20 for patchwork-qemu-devel@patchwork.kernel.org; Wed, 29 Jan 2020 07:24:08 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:52668) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iwmCz-0000Pk-Ks for qemu-devel@nongnu.org; Wed, 29 Jan 2020 07:12:39 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iwmCy-0003ne-8Z for qemu-devel@nongnu.org; Wed, 29 Jan 2020 07:12:37 -0500 Received: from mga09.intel.com ([134.134.136.24]:58727) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iwmCx-0001Rn-Ss for qemu-devel@nongnu.org; Wed, 29 Jan 2020 07:12:36 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 29 Jan 2020 04:11:53 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,377,1574150400"; d="scan'208";a="314071296" Received: from jacob-builder.jf.intel.com ([10.7.199.155]) by fmsmga001.fm.intel.com with ESMTP; 29 Jan 2020 04:11:53 -0800 From: "Liu, Yi L" To: qemu-devel@nongnu.org, david@gibson.dropbear.id.au, pbonzini@redhat.com, alex.williamson@redhat.com, peterx@redhat.com Subject: [RFC v3 21/25] intel_iommu: do not pass down pasid bind for PASID #0 Date: Wed, 29 Jan 2020 04:16:52 -0800 Message-Id: <1580300216-86172-22-git-send-email-yi.l.liu@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1580300216-86172-1-git-send-email-yi.l.liu@intel.com> References: <1580300216-86172-1-git-send-email-yi.l.liu@intel.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 134.134.136.24 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kevin.tian@intel.com, yi.l.liu@intel.com, Yi Sun , Eduardo Habkost , kvm@vger.kernel.org, mst@redhat.com, jun.j.tian@intel.com, eric.auger@redhat.com, yi.y.sun@intel.com, Jacob Pan , Richard Henderson , hao.wu@intel.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Liu Yi L RID_PASID field was introduced in VT-d 3.0 spec, it is used for DMA requests w/o PASID in scalable mode VT-d. It is also known as IOVA. And in VT-d 3.1 spec, there is definition on it: "Implementations not supporting RID_PASID capability (ECAP_REG.RPS is 0b), use a PASID value of 0 to perform address translation for requests without PASID." This patch adds a check against the PASIDs which are going to be bound to device. For PASID #0, it is not necessary to pass down pasid bind request for it since PASID #0 is used as RID_PASID for DMA requests without pasid. Further reason is current Intel vIOMMU supports gIOVA by shadowing guest 2nd level page table. However, in future, if guest IOMMU driver uses 1st level page table to store IOVA mappings, then guest IOVA support will also be done via nested translation. When gIOVA is over FLPT, then vIOMMU should pass down the pasid bind request for PASID #0 to host, host needs to bind the guest IOVA page table to a proper PASID. e.g PASID value in RID_PASID field for PF/VF if ECAP_REG.RPS is clear or default PASID for ADI (Assignable Device Interface in Scalable IOV solution). IOVA over FLPT support on Intel VT-d: https://lkml.org/lkml/2019/9/23/297 Cc: Kevin Tian Cc: Jacob Pan Cc: Peter Xu Cc: Yi Sun Cc: Paolo Bonzini Cc: Richard Henderson Cc: Eduardo Habkost Signed-off-by: Liu Yi L --- hw/i386/intel_iommu.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index 6422add..a511289 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -1883,6 +1883,16 @@ static int vtd_bind_guest_pasid(IntelIOMMUState *s, VTDBus *vtd_bus, struct iommu_gpasid_bind_data *g_bind_data; int ret = -1; + if (pasid < VTD_MIN_HPASID) { + /* + * If pasid < VTD_HPASID_MIN, this pasid is not allocated + * from host. No need to pass down the changes on it to host. + * TODO: when IOVA over FLPT is ready, this switch should be + * refined. + */ + return 0; + } + vtd_icx = vtd_bus->dev_icx[devfn]; if (!vtd_icx) { return ret;