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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 965A1C433E0 for ; Tue, 9 Feb 2021 06:23:20 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 401FF64EB9 for ; Tue, 9 Feb 2021 06:23:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 401FF64EB9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 17D93861C8; Tue, 9 Feb 2021 06:23:20 +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 y3P4JTKuLDGA; Tue, 9 Feb 2021 06:23:19 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id 8D6CB85FE4; Tue, 9 Feb 2021 06:23:19 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 77F42C0174; Tue, 9 Feb 2021 06:23:19 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 6F0A0C013A for ; Tue, 9 Feb 2021 06:23:18 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 6114986F93 for ; Tue, 9 Feb 2021 06:23:18 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Isxf3LejMqCY for ; Tue, 9 Feb 2021 06:23:17 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-pf1-f170.google.com (mail-pf1-f170.google.com [209.85.210.170]) by hemlock.osuosl.org (Postfix) with ESMTPS id CB2C086F8D for ; Tue, 9 Feb 2021 06:23:17 +0000 (UTC) Received: by mail-pf1-f170.google.com with SMTP id b145so11261993pfb.4 for ; Mon, 08 Feb 2021 22:23:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=eRi8Yzf5Y8qG5991xxXPsSC5LTyacs0FIIEghf5qlqE=; b=I1pOI9d2uMAOj25XXD6wAuAIs02PiqHn3vYbrTGQfRLUalLAaaWHj4AP66p1gZRw6c B3Fs+yS4m4TscPVDCU+jECnoKxyq5OcojOQ3UlsKgJX/2bKZw0g3cUyt8Lb9tyEzB+I7 d4RC5Ezyz3o4oj5hhy8N+DKnKQ48mOYCkG1WM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=eRi8Yzf5Y8qG5991xxXPsSC5LTyacs0FIIEghf5qlqE=; b=DCyTeIpPCPuiFAIetMEAFlZG7OOjYOHIevza48kefOwfWOAwM9xDXsucc4t00Pw4Fz rNz0IHobes+G/x6IRJQWPyedi7ousRw9+uf1xz7cNDsPI02cLCHwruxfFbjJaCRThjZw seP+TLvK5g/DsKDVjut3RlO5D+d6IKmzcu1X3JfjsjHJBJEzBN78q4ErErPifJirAYlD 2pjjmS8RYzbN3EwOA0uoGcLJqyDAAcs6gb4kiHPrc5T4EUEGxDSv5Vcd/+hiV+7rgx4S 158xYuKC1Oig338ObaY/22MZP+jiL9K1nGa8gXG3fQL1uOw2s4UDjX8i5bgvOkK841rV YKCg== X-Gm-Message-State: AOAM533VRZvUjB7As9E1ZrcObmn6O9E+1+tAgKY7xOHWsWNp64DueN/c T08oRjXK0uJPtisl+SHLpi9Lm8O/fyOwJQ== X-Google-Smtp-Source: ABdhPJxkt3Ed7T7cJDKzmZe4wszjCxFAf1leiOQT2ICOasIg3V/FKQTBEDaG8y6oYK6K58aSdM216A== X-Received: by 2002:a05:6a00:a8d:b029:1ba:71d1:fe3c with SMTP id b13-20020a056a000a8db02901ba71d1fe3cmr21262398pfl.51.1612851797444; Mon, 08 Feb 2021 22:23:17 -0800 (PST) Received: from localhost ([2401:fa00:1:10:a106:46e1:a999:81df]) by smtp.gmail.com with UTF8SMTPSA id a8sm1160332pjs.40.2021.02.08.22.23.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 08 Feb 2021 22:23:16 -0800 (PST) From: Claire Chang To: Rob Herring , mpe@ellerman.id.au, Joerg Roedel , Will Deacon , Frank Rowand , Konrad Rzeszutek Wilk , boris.ostrovsky@oracle.com, jgross@suse.com, Christoph Hellwig , Marek Szyprowski Subject: [PATCH v4 13/14] dt-bindings: of: Add restricted DMA pool Date: Tue, 9 Feb 2021 14:21:30 +0800 Message-Id: <20210209062131.2300005-14-tientzu@chromium.org> X-Mailer: git-send-email 2.30.0.478.g8a0d178c01-goog In-Reply-To: <20210209062131.2300005-1-tientzu@chromium.org> References: <20210209062131.2300005-1-tientzu@chromium.org> MIME-Version: 1.0 Cc: heikki.krogerus@linux.intel.com, peterz@infradead.org, benh@kernel.crashing.org, grant.likely@arm.com, paulus@samba.org, mingo@kernel.org, sstabellini@kernel.org, Saravana Kannan , xypron.glpk@gmx.de, "Rafael J . Wysocki" , Bartosz Golaszewski , xen-devel@lists.xenproject.org, Thierry Reding , linux-devicetree , linuxppc-dev@lists.ozlabs.org, Nicolas Boichat , Claire Chang , Dan Williams , Andy Shevchenko , Greg KH , Randy Dunlap , lkml , "list@263.net:IOMMU DRIVERS" , Jim Quinlan , Robin Murphy 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-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Introduce the new compatible string, restricted-dma-pool, for restricted DMA. One can specify the address and length of the restricted DMA memory region by restricted-dma-pool in the reserved-memory node. Signed-off-by: Claire Chang --- .../reserved-memory/reserved-memory.txt | 24 +++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt index e8d3096d922c..fc9a12c2f679 100644 --- a/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt +++ b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt @@ -51,6 +51,20 @@ compatible (optional) - standard definition used as a shared pool of DMA buffers for a set of devices. It can be used by an operating system to instantiate the necessary pool management subsystem if necessary. + - restricted-dma-pool: This indicates a region of memory meant to be + used as a pool of restricted DMA buffers for a set of devices. The + memory region would be the only region accessible to those devices. + When using this, the no-map and reusable properties must not be set, + so the operating system can create a virtual mapping that will be used + for synchronization. The main purpose for restricted DMA is to + mitigate the lack of DMA access control on systems without an IOMMU, + which could result in the DMA accessing the system memory at + unexpected times and/or unexpected addresses, possibly leading to data + leakage or corruption. The feature on its own provides a basic level + of protection against the DMA overwriting buffer contents at + unexpected times. However, to protect against general data leakage and + system memory corruption, the system needs to provide way to lock down + the memory access, e.g., MPU. - vendor specific string in the form ,[-] no-map (optional) - empty property - Indicates the operating system must not create a virtual mapping @@ -120,6 +134,11 @@ one for multimedia processing (named multimedia-memory@77000000, 64MiB). compatible = "acme,multimedia-memory"; reg = <0x77000000 0x4000000>; }; + + restricted_dma_mem_reserved: restricted_dma_mem_reserved { + compatible = "restricted-dma-pool"; + reg = <0x50000000 0x400000>; + }; }; /* ... */ @@ -138,4 +157,9 @@ one for multimedia processing (named multimedia-memory@77000000, 64MiB). memory-region = <&multimedia_reserved>; /* ... */ }; + + pcie_device: pcie_device@0,0 { + memory-region = <&restricted_dma_mem_reserved>; + /* ... */ + }; }; -- 2.30.0.478.g8a0d178c01-goog _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu