From patchwork Sat Jul 4 11:36:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yi Liu X-Patchwork-Id: 11643585 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 49B7E913 for ; Sat, 4 Jul 2020 11:46:21 +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 2A6992084C for ; Sat, 4 Jul 2020 11:46:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2A6992084C 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]:44208 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jrgce-000055-Fq for patchwork-qemu-devel@patchwork.kernel.org; Sat, 04 Jul 2020 07:46:20 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52722) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jrgOD-0001u0-6M for qemu-devel@nongnu.org; Sat, 04 Jul 2020 07:31:25 -0400 Received: from mga05.intel.com ([192.55.52.43]:24797) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jrgOA-0004KM-5A for qemu-devel@nongnu.org; Sat, 04 Jul 2020 07:31:24 -0400 IronPort-SDR: ho4Q3rifdEwOHL1tkcns7ii4O/S7MJ4RfleBYZuEOQdVZYImx7hsQuvu9VksS2fj5+ZXxwzFgX f5LQJGJ22/mg== X-IronPort-AV: E=McAfee;i="6000,8403,9671"; a="232105538" X-IronPort-AV: E=Sophos;i="5.75,311,1589266800"; d="scan'208";a="232105538" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Jul 2020 04:30:25 -0700 IronPort-SDR: KATvQCGq0Q/00fqUtj1cfG1JCTO6a/PXblBViT7mfnAegAECtGiu5FwfHPYWrueZKBNf1qdMqY 96ROiUorKuJg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,311,1589266800"; d="scan'208";a="266146839" Received: from jacob-builder.jf.intel.com ([10.7.199.155]) by fmsmga007.fm.intel.com with ESMTP; 04 Jul 2020 04:30:25 -0700 From: Liu Yi L To: qemu-devel@nongnu.org, alex.williamson@redhat.com, peterx@redhat.com Subject: [RFC v7 20/25] intel_iommu: do not pass down pasid bind for PASID #0 Date: Sat, 4 Jul 2020 04:36:44 -0700 Message-Id: <1593862609-36135-21-git-send-email-yi.l.liu@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1593862609-36135-1-git-send-email-yi.l.liu@intel.com> References: <1593862609-36135-1-git-send-email-yi.l.liu@intel.com> Received-SPF: pass client-ip=192.55.52.43; envelope-from=yi.l.liu@intel.com; helo=mga05.intel.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/04 07:30:14 X-ACL-Warn: Detected OS = FreeBSD 9.x or newer [fuzzy] X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN X-Spam_action: no action 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: jean-philippe@linaro.org, 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 , pbonzini@redhat.com, hao.wu@intel.com, jasowang@redhat.com, Richard Henderson , david@gibson.dropbear.id.au Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" 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 Reviewed-by: Peter Xu 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 9977e70..fb72076 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -1893,6 +1893,16 @@ static int vtd_bind_guest_pasid(IntelIOMMUState *s, VTDBus *vtd_bus, HostIOMMUContext *iommu_ctx; int ret = -1; + if (pasid < VTD_HPASID_MIN) { + /* + * 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_dev_icx = vtd_bus->dev_icx[devfn]; if (!vtd_dev_icx) { /* means no need to go further, e.g. for emulated devices */