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 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5EE1EC433F5 for ; Mon, 13 Dec 2021 08:26:40 +0000 (UTC) Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-107-dMkyYUZAOY-4XeM0aUg5tA-1; Mon, 13 Dec 2021 03:26:35 -0500 X-MC-Unique: dMkyYUZAOY-4XeM0aUg5tA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D93A8192FDA1; Mon, 13 Dec 2021 08:26:30 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7142F60C04; Mon, 13 Dec 2021 08:26:30 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 782341809CB8; Mon, 13 Dec 2021 08:26:29 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 1BD8ORlK004340 for ; Mon, 13 Dec 2021 03:24:27 -0500 Received: by smtp.corp.redhat.com (Postfix) id 6BE4C4010FDD; Mon, 13 Dec 2021 08:24:27 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast10.extmail.prod.ext.rdu2.redhat.com [10.11.55.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6745F4010E97 for ; Mon, 13 Dec 2021 08:24:27 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [205.139.110.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 53CF51C03363 for ; Mon, 13 Dec 2021 08:24:27 +0000 (UTC) Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-466-Kfpk2NIPMv6_25zpRIT9GA-1; Mon, 13 Dec 2021 03:24:23 -0500 X-MC-Unique: Kfpk2NIPMv6_25zpRIT9GA-1 Received: by verein.lst.de (Postfix, from userid 2407) id 60ABF68BFE; Mon, 13 Dec 2021 09:24:20 +0100 (CET) Date: Mon, 13 Dec 2021 09:24:20 +0100 From: Christoph Hellwig To: Dan Williams Message-ID: <20211213082420.GC21462@lst.de> References: <20211209063828.18944-1-hch@lst.de> <20211209063828.18944-5-hch@lst.de> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.84 on 10.11.54.1 X-loop: dm-devel@redhat.com Cc: Linux NVDIMM , linux-s390 , Dave Jiang , Vasily Gorbik , Mike Snitzer , Miklos Szeredi , Vishal Verma , Heiko Carstens , Matthew Wilcox , virtualization@lists.linux-foundation.org, Christian Borntraeger , device-mapper development , Vivek Goyal , Stefan Hajnoczi , linux-fsdevel , Ira Weiny , Christoph Hellwig , Alasdair Kergon Subject: Re: [dm-devel] [PATCH 4/5] dax: remove the copy_from_iter and copy_to_iter methods X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Sun, Dec 12, 2021 at 06:39:16AM -0800, Dan Williams wrote: > > /* flag to check if device supports synchronous flush */ > > DAXDEV_SYNC, > > + /* do not use uncached operations to write data */ > > + DAXDEV_CACHED, > > + /* do not use mcsafe operations to read data */ > > + DAXDEV_NOMCSAFE, > > Linus did not like the mcsafe name, and this brings it back. Let's > flip the polarity to positively indicate which routine to use, and to > match the 'nofault' style which says "copy and handle faults". > > /* do not leave the caches dirty after writes */ > DAXDEV_NOCACHE > > /* handle CPU fetch exceptions during reads */ > DAXDEV_NOMC > > ...and then flip the use cases around. Sure we can do that. But let's finish the discussion if we actually need the virtiofs special casing, as it seems pretty fishy in many aspects. -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel 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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 91CBAC433EF for ; Mon, 13 Dec 2021 08:24:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232959AbhLMIYc (ORCPT ); Mon, 13 Dec 2021 03:24:32 -0500 Received: from verein.lst.de ([213.95.11.211]:46663 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233027AbhLMIYX (ORCPT ); Mon, 13 Dec 2021 03:24:23 -0500 Received: by verein.lst.de (Postfix, from userid 2407) id 60ABF68BFE; Mon, 13 Dec 2021 09:24:20 +0100 (CET) Date: Mon, 13 Dec 2021 09:24:20 +0100 From: Christoph Hellwig To: Dan Williams Cc: Christoph Hellwig , Vishal Verma , Dave Jiang , Alasdair Kergon , Mike Snitzer , Ira Weiny , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Vivek Goyal , Stefan Hajnoczi , Miklos Szeredi , Matthew Wilcox , device-mapper development , Linux NVDIMM , linux-s390 , linux-fsdevel , virtualization@lists.linux-foundation.org Subject: Re: [PATCH 4/5] dax: remove the copy_from_iter and copy_to_iter methods Message-ID: <20211213082420.GC21462@lst.de> References: <20211209063828.18944-1-hch@lst.de> <20211209063828.18944-5-hch@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) Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On Sun, Dec 12, 2021 at 06:39:16AM -0800, Dan Williams wrote: > > /* flag to check if device supports synchronous flush */ > > DAXDEV_SYNC, > > + /* do not use uncached operations to write data */ > > + DAXDEV_CACHED, > > + /* do not use mcsafe operations to read data */ > > + DAXDEV_NOMCSAFE, > > Linus did not like the mcsafe name, and this brings it back. Let's > flip the polarity to positively indicate which routine to use, and to > match the 'nofault' style which says "copy and handle faults". > > /* do not leave the caches dirty after writes */ > DAXDEV_NOCACHE > > /* handle CPU fetch exceptions during reads */ > DAXDEV_NOMC > > ...and then flip the use cases around. Sure we can do that. But let's finish the discussion if we actually need the virtiofs special casing, as it seems pretty fishy in many aspects. 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 Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E3FE9C433EF for ; Mon, 13 Dec 2021 08:24:28 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 9286D60EF1; Mon, 13 Dec 2021 08:24:28 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ogeK3Od4vnCd; Mon, 13 Dec 2021 08:24:28 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp3.osuosl.org (Postfix) with ESMTPS id 5C48460ED3; Mon, 13 Dec 2021 08:24:27 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 42437C002F; Mon, 13 Dec 2021 08:24:27 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 1BAA7C0012 for ; Mon, 13 Dec 2021 08:24:25 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id ED21440162 for ; Mon, 13 Dec 2021 08:24:24 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id NqmL7uwYmVde for ; Mon, 13 Dec 2021 08:24:24 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by smtp2.osuosl.org (Postfix) with ESMTPS id 415B14011D for ; Mon, 13 Dec 2021 08:24:24 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 60ABF68BFE; Mon, 13 Dec 2021 09:24:20 +0100 (CET) Date: Mon, 13 Dec 2021 09:24:20 +0100 From: Christoph Hellwig To: Dan Williams Subject: Re: [PATCH 4/5] dax: remove the copy_from_iter and copy_to_iter methods Message-ID: <20211213082420.GC21462@lst.de> References: <20211209063828.18944-1-hch@lst.de> <20211209063828.18944-5-hch@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Cc: Linux NVDIMM , linux-s390 , Dave Jiang , Vasily Gorbik , Mike Snitzer , Miklos Szeredi , Vishal Verma , Heiko Carstens , Matthew Wilcox , virtualization@lists.linux-foundation.org, Christian Borntraeger , device-mapper development , Vivek Goyal , Stefan Hajnoczi , linux-fsdevel , Ira Weiny , Christoph Hellwig , Alasdair Kergon X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Sun, Dec 12, 2021 at 06:39:16AM -0800, Dan Williams wrote: > > /* flag to check if device supports synchronous flush */ > > DAXDEV_SYNC, > > + /* do not use uncached operations to write data */ > > + DAXDEV_CACHED, > > + /* do not use mcsafe operations to read data */ > > + DAXDEV_NOMCSAFE, > > Linus did not like the mcsafe name, and this brings it back. Let's > flip the polarity to positively indicate which routine to use, and to > match the 'nofault' style which says "copy and handle faults". > > /* do not leave the caches dirty after writes */ > DAXDEV_NOCACHE > > /* handle CPU fetch exceptions during reads */ > DAXDEV_NOMC > > ...and then flip the use cases around. Sure we can do that. But let's finish the discussion if we actually need the virtiofs special casing, as it seems pretty fishy in many aspects. _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization