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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 3E69DC04AB6 for ; Tue, 28 May 2019 11:52:42 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (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 1DB1C2075B for ; Tue, 28 May 2019 11:52:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1DB1C2075B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 8531D1C4D; Tue, 28 May 2019 11:52:19 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id B09C51BAD for ; Tue, 28 May 2019 11:51:13 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 40B6981A for ; Tue, 28 May 2019 11:51:13 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E6B4E3092657; Tue, 28 May 2019 11:51:11 +0000 (UTC) Received: from laptop.redhat.com (ovpn-116-67.ams2.redhat.com [10.36.116.67]) by smtp.corp.redhat.com (Postfix) with ESMTP id 13EB95D9CC; Tue, 28 May 2019 11:51:05 +0000 (UTC) From: Eric Auger To: eric.auger.pro@gmail.com, eric.auger@redhat.com, joro@8bytes.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, dwmw2@infradead.org, robin.murphy@arm.com Subject: [PATCH v5 7/7] iommu/vt-d: Differentiate relaxable and non relaxable RMRRs Date: Tue, 28 May 2019 13:50:25 +0200 Message-Id: <20190528115025.17194-8-eric.auger@redhat.com> In-Reply-To: <20190528115025.17194-1-eric.auger@redhat.com> References: <20190528115025.17194-1-eric.auger@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.43]); Tue, 28 May 2019 11:51:12 +0000 (UTC) Cc: jean-philippe.brucker@arm.com, alex.williamson@redhat.com X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org Now we have a new IOMMU_RESV_DIRECT_RELAXABLE reserved memory region type, let's report USB and GFX RMRRs as relaxable ones. We introduce a new device_rmrr_is_relaxable() helper to check whether the rmrr belongs to the relaxable category. This allows to have a finer reporting at IOMMU API level of reserved memory regions. This will be exploitable by VFIO to define the usable IOVA range and detect potential conflicts between the guest physical address space and host reserved regions. Signed-off-by: Eric Auger --- v3 -> v4: - introduce device_rmrr_is_relaxable and reshuffle the comments --- drivers/iommu/intel-iommu.c | 55 +++++++++++++++++++++++++++---------- 1 file changed, 40 insertions(+), 15 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 9302351818ab..01c82f848470 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -2920,6 +2920,36 @@ static bool device_has_rmrr(struct device *dev) return false; } +/* + * device_rmrr_is_relaxable - Test whether the RMRR of this device + * is relaxable (ie. is allowed to be not enforced under some conditions) + * + * @dev: device handle + * + * We assume that PCI USB devices with RMRRs have them largely + * for historical reasons and that the RMRR space is not actively used post + * boot. This exclusion may change if vendors begin to abuse it. + * + * The same exception is made for graphics devices, with the requirement that + * any use of the RMRR regions will be torn down before assigning the device + * to a guest. + * + * Return: true if the RMRR is relaxable + */ +static bool device_rmrr_is_relaxable(struct device *dev) +{ + struct pci_dev *pdev; + + if (!dev_is_pci(dev)) + return false; + + pdev = to_pci_dev(dev); + if (IS_USB_DEVICE(pdev) || IS_GFX_DEVICE(pdev)) + return true; + else + return false; +} + /* * There are a couple cases where we need to restrict the functionality of * devices associated with RMRRs. The first is when evaluating a device for @@ -2934,25 +2964,16 @@ static bool device_has_rmrr(struct device *dev) * We therefore prevent devices associated with an RMRR from participating in * the IOMMU API, which eliminates them from device assignment. * - * In both cases we assume that PCI USB devices with RMRRs have them largely - * for historical reasons and that the RMRR space is not actively used post - * boot. This exclusion may change if vendors begin to abuse it. - * - * The same exception is made for graphics devices, with the requirement that - * any use of the RMRR regions will be torn down before assigning the device - * to a guest. + * In both cases, devices which have relaxable RMRRs are not concerned by this + * restriction. See device_rmrr_is_relaxable comment. */ static bool device_is_rmrr_locked(struct device *dev) { if (!device_has_rmrr(dev)) return false; - if (dev_is_pci(dev)) { - struct pci_dev *pdev = to_pci_dev(dev); - - if (IS_USB_DEVICE(pdev) || IS_GFX_DEVICE(pdev)) - return false; - } + if (device_rmrr_is_relaxable(dev)) + return false; return true; } @@ -5494,6 +5515,7 @@ static void intel_iommu_get_resv_regions(struct device *device, for_each_active_dev_scope(rmrr->devices, rmrr->devices_cnt, i, i_dev) { struct iommu_resv_region *resv; + enum iommu_resv_type type; size_t length; if (i_dev != device && @@ -5501,9 +5523,12 @@ static void intel_iommu_get_resv_regions(struct device *device, continue; length = rmrr->end_address - rmrr->base_address + 1; + + type = device_rmrr_is_relaxable(device) ? + IOMMU_RESV_DIRECT_RELAXABLE : IOMMU_RESV_DIRECT; + resv = iommu_alloc_resv_region(rmrr->base_address, - length, prot, - IOMMU_RESV_DIRECT); + length, prot, type); if (!resv) break; -- 2.20.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu