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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 72840C04AB5 for ; Mon, 3 Jun 2019 22:05:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5538326647 for ; Mon, 3 Jun 2019 22:05:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726867AbfFCWFm (ORCPT ); Mon, 3 Jun 2019 18:05:42 -0400 Received: from mga11.intel.com ([192.55.52.93]:1031 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726205AbfFCWFj (ORCPT ); Mon, 3 Jun 2019 18:05:39 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Jun 2019 15:05:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,548,1549958400"; d="scan'208";a="181310106" Received: from jacob-builder.jf.intel.com (HELO jacob-builder) ([10.7.199.155]) by fmsmga002.fm.intel.com with ESMTP; 03 Jun 2019 15:05:38 -0700 Date: Mon, 3 Jun 2019 15:08:42 -0700 From: Jacob Pan To: Jean-Philippe Brucker Cc: joro@8bytes.org, alex.williamson@redhat.com, eric.auger@redhat.com, ashok.raj@intel.com, yi.l.liu@intel.com, robdclark@gmail.com, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, robin.murphy@arm.com, jacob.jun.pan@linux.intel.com Subject: Re: [PATCH v2 2/4] iommu: Introduce device fault data Message-ID: <20190603150842.11070cfd@jacob-builder> In-Reply-To: <20190603145749.46347-3-jean-philippe.brucker@arm.com> References: <20190603145749.46347-1-jean-philippe.brucker@arm.com> <20190603145749.46347-3-jean-philippe.brucker@arm.com> Organization: OTC X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 3 Jun 2019 15:57:47 +0100 Jean-Philippe Brucker wrote: > +/** > + * struct iommu_fault_page_request - Page Request data > + * @flags: encodes whether the corresponding fields are valid and > whether this > + * is the last page in group (IOMMU_FAULT_PAGE_REQUEST_* > values) > + * @pasid: Process Address Space ID > + * @grpid: Page Request Group Index > + * @perm: requested page permissions (IOMMU_FAULT_PERM_* values) > + * @addr: page address > + * @private_data: device-specific private information > + */ > +struct iommu_fault_page_request { > +#define IOMMU_FAULT_PAGE_REQUEST_PASID_VALID (1 << 0) > +#define IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE (1 << 1) > +#define IOMMU_FAULT_PAGE_REQUEST_PRIV_DATA (1 << 2) > + __u32 flags; > + __u32 pasid; > + __u32 grpid; > + __u32 perm; > + __u64 addr; > + __u64 private_data[2]; > +}; > + Just a thought, for non-identity G-H PASID management. We could pass on guest PASID in PRQ to save a lookup in QEMU. In this case, QEMU allocate a GPASID for vIOMMU then a host PASID for pIOMMU. QEMU has a G->H lookup. When PRQ comes in to the pIOMMU with HPASID, IOMMU driver can retrieve GPASID from the bind data then report to the guest via VFIO. In this case QEMU does not need to do a H->G PASID lookup. Should we add a gpasid field here? or we can add a flag and field later, up to you. Thanks, Jacob