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 62C69C41621 for ; Tue, 24 Mar 2020 07:54:07 +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 41DB520724 for ; Tue, 24 Mar 2020 07:54:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 41DB520724 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de 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 1D6EE845D6; Tue, 24 Mar 2020 07:54:07 +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 iR8-rYsQH3Ck; Tue, 24 Mar 2020 07:54:06 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id C2E17845C6; Tue, 24 Mar 2020 07:54:06 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id BD670C089F; Tue, 24 Mar 2020 07:54:06 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 23583C0177 for ; Tue, 24 Mar 2020 07:54:06 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 1F2F788B52 for ; Tue, 24 Mar 2020 07:54:06 +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 9fJoJy3jhbeX for ; Tue, 24 Mar 2020 07:54:05 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by hemlock.osuosl.org (Postfix) with ESMTPS id DCBBE88B15 for ; Tue, 24 Mar 2020 07:54:04 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id E210B68BFE; Tue, 24 Mar 2020 08:54:02 +0100 (CET) Date: Tue, 24 Mar 2020 08:54:02 +0100 From: Christoph Hellwig To: Alexey Kardashevskiy Subject: Re: [PATCH 1/2] dma-mapping: add a dma_ops_bypass flag to struct device Message-ID: <20200324075402.GJ23447@lst.de> References: <20200320141640.366360-1-hch@lst.de> <20200320141640.366360-2-hch@lst.de> <2f31d0dd-aa7e-8b76-c8a1-5759fda5afc9@ozlabs.ru> <20200323083705.GA31245@lst.de> <20200323085059.GA32528@lst.de> <87sghz2ibh.fsf@linux.ibm.com> <20200323172256.GB31269@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Cc: Greg Kroah-Hartman , Robin Murphy , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, "Aneesh Kumar K.V" , linuxppc-dev@lists.ozlabs.org, Christoph Hellwig 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" On Tue, Mar 24, 2020 at 02:05:54PM +1100, Alexey Kardashevskiy wrote: > This is for persistent memory which you can DMA to/from but yet it does > not appear in the system as a normal memory and therefore requires > special handling anyway (O_DIRECT or DAX, I do not know the exact > mechanics). All other devices in the system should just run as usual, > i.e. use 1:1 mapping if possible. On other systems (x86 and arm) pmem as long as it is page backed does not require any special handling. This must be some weird way powerpc fucked up again, and I suspect you'll have to suffer from it. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu 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 56E98C4332B for ; Tue, 24 Mar 2020 07:56:27 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 0E55E20724 for ; Tue, 24 Mar 2020 07:56:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0E55E20724 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 48mk8m0wg3zDqyq for ; Tue, 24 Mar 2020 18:56:24 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=verein.lst.de; envelope-from=hch@lst.de; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 48mk662KTMzDqZl for ; Tue, 24 Mar 2020 18:54:06 +1100 (AEDT) Received: by verein.lst.de (Postfix, from userid 2407) id E210B68BFE; Tue, 24 Mar 2020 08:54:02 +0100 (CET) Date: Tue, 24 Mar 2020 08:54:02 +0100 From: Christoph Hellwig To: Alexey Kardashevskiy Subject: Re: [PATCH 1/2] dma-mapping: add a dma_ops_bypass flag to struct device Message-ID: <20200324075402.GJ23447@lst.de> References: <20200320141640.366360-1-hch@lst.de> <20200320141640.366360-2-hch@lst.de> <2f31d0dd-aa7e-8b76-c8a1-5759fda5afc9@ozlabs.ru> <20200323083705.GA31245@lst.de> <20200323085059.GA32528@lst.de> <87sghz2ibh.fsf@linux.ibm.com> <20200323172256.GB31269@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Greg Kroah-Hartman , Joerg Roedel , Robin Murphy , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, "Aneesh Kumar K.V" , linuxppc-dev@lists.ozlabs.org, Christoph Hellwig , Lu Baolu Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Tue, Mar 24, 2020 at 02:05:54PM +1100, Alexey Kardashevskiy wrote: > This is for persistent memory which you can DMA to/from but yet it does > not appear in the system as a normal memory and therefore requires > special handling anyway (O_DIRECT or DAX, I do not know the exact > mechanics). All other devices in the system should just run as usual, > i.e. use 1:1 mapping if possible. On other systems (x86 and arm) pmem as long as it is page backed does not require any special handling. This must be some weird way powerpc fucked up again, and I suspect you'll have to suffer from it. 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 00553C4332B for ; Tue, 24 Mar 2020 07:54:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CEF5B20724 for ; Tue, 24 Mar 2020 07:54:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727530AbgCXHyF (ORCPT ); Tue, 24 Mar 2020 03:54:05 -0400 Received: from verein.lst.de ([213.95.11.211]:34305 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725869AbgCXHyF (ORCPT ); Tue, 24 Mar 2020 03:54:05 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id E210B68BFE; Tue, 24 Mar 2020 08:54:02 +0100 (CET) Date: Tue, 24 Mar 2020 08:54:02 +0100 From: Christoph Hellwig To: Alexey Kardashevskiy Cc: Christoph Hellwig , "Aneesh Kumar K.V" , iommu@lists.linux-foundation.org, linuxppc-dev@lists.ozlabs.org, Lu Baolu , Greg Kroah-Hartman , Joerg Roedel , Robin Murphy , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] dma-mapping: add a dma_ops_bypass flag to struct device Message-ID: <20200324075402.GJ23447@lst.de> References: <20200320141640.366360-1-hch@lst.de> <20200320141640.366360-2-hch@lst.de> <2f31d0dd-aa7e-8b76-c8a1-5759fda5afc9@ozlabs.ru> <20200323083705.GA31245@lst.de> <20200323085059.GA32528@lst.de> <87sghz2ibh.fsf@linux.ibm.com> <20200323172256.GB31269@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 24, 2020 at 02:05:54PM +1100, Alexey Kardashevskiy wrote: > This is for persistent memory which you can DMA to/from but yet it does > not appear in the system as a normal memory and therefore requires > special handling anyway (O_DIRECT or DAX, I do not know the exact > mechanics). All other devices in the system should just run as usual, > i.e. use 1:1 mapping if possible. On other systems (x86 and arm) pmem as long as it is page backed does not require any special handling. This must be some weird way powerpc fucked up again, and I suspect you'll have to suffer from it.