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=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 38183C04AB6 for ; Mon, 3 Jun 2019 06:54:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 11B2E27C51 for ; Mon, 3 Jun 2019 06:54:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727395AbfFCGyB (ORCPT ); Mon, 3 Jun 2019 02:54:01 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35430 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727372AbfFCGx6 (ORCPT ); Mon, 3 Jun 2019 02:53:58 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 673323086226; Mon, 3 Jun 2019 06:53:57 +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 D962C1001E67; Mon, 3 Jun 2019 06:53:53 +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 Cc: alex.williamson@redhat.com, shameerali.kolothum.thodi@huawei.com, jean-philippe.brucker@arm.com Subject: [PATCH v6 2/7] iommu/vt-d: Duplicate iommu_resv_region objects per device list Date: Mon, 3 Jun 2019 08:53:31 +0200 Message-Id: <20190603065336.10524-3-eric.auger@redhat.com> In-Reply-To: <20190603065336.10524-1-eric.auger@redhat.com> References: <20190603065336.10524-1-eric.auger@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Mon, 03 Jun 2019 06:53:57 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org intel_iommu_get_resv_regions() aims to return the list of reserved regions accessible by a given @device. However several devices can access the same reserved memory region and when building the list it is not safe to use a single iommu_resv_region object, whose container is the RMRR. This iommu_resv_region must be duplicated per device reserved region list. Let's remove the struct iommu_resv_region from the RMRR unit and allocate the iommu_resv_region directly in intel_iommu_get_resv_regions(). We hold the dmar_global_lock instead of the rcu-lock to allow sleeping. Fixes: 0659b8dc45a6 ("iommu/vt-d: Implement reserved region get/put callbacks") Signed-off-by: Eric Auger Reviewed-by: Lu Baolu --- v5 -> v6: - added space between | operands - dmar_global_lock down_read/up_read instead of write - added Lu's R-b v4 -> v5 - replace rcu-lock by the dmar_global_lock --- drivers/iommu/intel-iommu.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index a209199f3af6..4dc012966964 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -322,7 +322,6 @@ struct dmar_rmrr_unit { u64 end_address; /* reserved end address */ struct dmar_dev_scope *devices; /* target devices */ int devices_cnt; /* target device count */ - struct iommu_resv_region *resv; /* reserved region handle */ }; struct dmar_atsr_unit { @@ -4205,7 +4204,6 @@ static inline void init_iommu_pm_ops(void) {} int __init dmar_parse_one_rmrr(struct acpi_dmar_header *header, void *arg) { struct acpi_dmar_reserved_memory *rmrr; - int prot = DMA_PTE_READ|DMA_PTE_WRITE; struct dmar_rmrr_unit *rmrru; size_t length; @@ -4219,22 +4217,16 @@ int __init dmar_parse_one_rmrr(struct acpi_dmar_header *header, void *arg) rmrru->end_address = rmrr->end_address; length = rmrr->end_address - rmrr->base_address + 1; - rmrru->resv = iommu_alloc_resv_region(rmrr->base_address, length, prot, - IOMMU_RESV_DIRECT); - if (!rmrru->resv) - goto free_rmrru; rmrru->devices = dmar_alloc_dev_scope((void *)(rmrr + 1), ((void *)rmrr) + rmrr->header.length, &rmrru->devices_cnt); if (rmrru->devices_cnt && rmrru->devices == NULL) - goto free_all; + goto free_rmrru; list_add(&rmrru->list, &dmar_rmrr_units); return 0; -free_all: - kfree(rmrru->resv); free_rmrru: kfree(rmrru); out: @@ -4452,7 +4444,6 @@ static void intel_iommu_free_dmars(void) list_for_each_entry_safe(rmrru, rmrr_n, &dmar_rmrr_units, list) { list_del(&rmrru->list); dmar_free_dev_scope(&rmrru->devices, &rmrru->devices_cnt); - kfree(rmrru->resv); kfree(rmrru); } @@ -5470,22 +5461,33 @@ static void intel_iommu_remove_device(struct device *dev) static void intel_iommu_get_resv_regions(struct device *device, struct list_head *head) { + int prot = DMA_PTE_READ | DMA_PTE_WRITE; struct iommu_resv_region *reg; struct dmar_rmrr_unit *rmrr; struct device *i_dev; int i; - rcu_read_lock(); + down_read(&dmar_global_lock); for_each_rmrr_units(rmrr) { for_each_active_dev_scope(rmrr->devices, rmrr->devices_cnt, i, i_dev) { + struct iommu_resv_region *resv; + size_t length; + if (i_dev != device) continue; - list_add_tail(&rmrr->resv->list, head); + length = rmrr->end_address - rmrr->base_address + 1; + resv = iommu_alloc_resv_region(rmrr->base_address, + length, prot, + IOMMU_RESV_DIRECT); + if (!resv) + break; + + list_add_tail(&resv->list, head); } } - rcu_read_unlock(); + up_read(&dmar_global_lock); reg = iommu_alloc_resv_region(IOAPIC_RANGE_START, IOAPIC_RANGE_END - IOAPIC_RANGE_START + 1, @@ -5500,10 +5502,8 @@ static void intel_iommu_put_resv_regions(struct device *dev, { struct iommu_resv_region *entry, *next; - list_for_each_entry_safe(entry, next, head, list) { - if (entry->type == IOMMU_RESV_MSI) - kfree(entry); - } + list_for_each_entry_safe(entry, next, head, list) + kfree(entry); } int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct device *dev) -- 2.20.1