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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 99DDCC2D0D1 for ; Wed, 18 Dec 2019 02:42:53 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 6D2B224676 for ; Wed, 18 Dec 2019 02:42:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6D2B224676 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 3168822621; Wed, 18 Dec 2019 02:42:53 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QNd5gsxuMfUx; Wed, 18 Dec 2019 02:42:52 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id 477751FEAE; Wed, 18 Dec 2019 02:42:52 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 2CDC2C1AE8; Wed, 18 Dec 2019 02:42:52 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 1AD04C077D for ; Wed, 18 Dec 2019 02:42:50 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id BA7CF81B1D for ; Wed, 18 Dec 2019 02:42:49 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id MjVNhJ8YYAuT for ; Wed, 18 Dec 2019 02:42:49 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by fraxinus.osuosl.org (Postfix) with ESMTPS id 20A228085A for ; Wed, 18 Dec 2019 02:42:49 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Dec 2019 18:42:48 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,327,1571727600"; d="scan'208";a="227712787" Received: from allen-box.sh.intel.com (HELO [10.239.159.136]) ([10.239.159.136]) by orsmga002.jf.intel.com with ESMTP; 17 Dec 2019 18:42:46 -0800 Subject: Re: [PATCH v8 02/10] iommu/vt-d: Add nested translation helper function To: Jacob Pan , iommu@lists.linux-foundation.org, LKML , Joerg Roedel , David Woodhouse References: <1576524252-79116-1-git-send-email-jacob.jun.pan@linux.intel.com> <1576524252-79116-3-git-send-email-jacob.jun.pan@linux.intel.com> From: Lu Baolu Message-ID: <6192b57c-12ab-ec6c-ab95-d9b9bff3efad@linux.intel.com> Date: Wed, 18 Dec 2019 10:41:53 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.1 MIME-Version: 1.0 In-Reply-To: <1576524252-79116-3-git-send-email-jacob.jun.pan@linux.intel.com> Content-Language: en-US Cc: Yi L , "Tian, Kevin" , Raj Ashok X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Hi again, On 12/17/19 3:24 AM, Jacob Pan wrote: > +/** > + * intel_pasid_setup_nested() - Set up PASID entry for nested translation > + * which is used for vSVA. The first level page tables are used for > + * GVA-GPA or GIOVA-GPA translation in the guest, second level page tables > + * are used for GPA-HPA translation. > + * > + * @iommu: Iommu which the device belong to > + * @dev: Device to be set up for translation > + * @gpgd: FLPTPTR: First Level Page translation pointer in GPA > + * @pasid: PASID to be programmed in the device PASID table > + * @pasid_data: Additional PASID info from the guest bind request > + * @domain: Domain info for setting up second level page tables > + * @addr_width: Address width of the first level (guest) > + */ > +int intel_pasid_setup_nested(struct intel_iommu *iommu, > + struct device *dev, pgd_t *gpgd, > + int pasid, struct iommu_gpasid_bind_data_vtd *pasid_data, > + struct dmar_domain *domain, > + int addr_width) > +{ > + struct pasid_entry *pte; > + struct dma_pte *pgd; > + u64 pgd_val; > + int agaw; > + u16 did; > + > + if (!ecap_nest(iommu->ecap)) { > + pr_err("IOMMU: %s: No nested translation support\n", > + iommu->name); > + return -EINVAL; > + } > + > + pte = intel_pasid_get_entry(dev, pasid); > + if (WARN_ON(!pte)) > + return -EINVAL; > + > + pasid_clear_entry(pte); In some cases, e.g. nested mode for GIOVA-HPA, the PASID entry might have already been setup for second level translation. (This could be checked with the Present bit.) Hence, it's safe to flush caches here. Or, maybe intel_pasid_tear_down_entry() is more suitable? Best regards, baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu