From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AA9952C81 for ; Fri, 22 Oct 2021 05:34:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=xcBYXoniZzY7ZLTTZ2jfTzgN29460ApB4jiwLahdOXs=; b=wi8pPE/qofJdTPE+Mth0DB7fNI rLPT6fRiQAjOngtkmahECmF4xzDu8RZ+I/Bq734xorg82BkoG4CBsYixbbryGpWiTbMGMW53DukOP YTn3+gU8/n5KPFtd5gq+hgqf8YPpCjFqy6j+Flp4pEEuq2my4/sz0/BIdeXcDe+Z7fioDGk77K1si QlkDEAuPF2HNERwYHk7orbA89KtEJOGSzrBOzpoZh72/Pb863SQdM1QLRqbOnjHw00yWQLJywtl+N V+3W/8U+69VhnkaEcfn7BnEWN0S9AvZaE3zTOp7odX3xsFVaAhE5U0RUMtrOqpTqi2gqYoORmRq1g /XqKfgQg==; Received: from hch by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1mdnBN-009lTo-6z; Fri, 22 Oct 2021 05:33:33 +0000 Date: Thu, 21 Oct 2021 22:33:33 -0700 From: Christoph Hellwig To: Jane Chu Cc: Christoph Hellwig , "david@fromorbit.com" , "djwong@kernel.org" , "dan.j.williams@intel.com" , "vishal.l.verma@intel.com" , "dave.jiang@intel.com" , "agk@redhat.com" , "snitzer@redhat.com" , "dm-devel@redhat.com" , "ira.weiny@intel.com" , "willy@infradead.org" , "vgoyal@redhat.com" , "linux-fsdevel@vger.kernel.org" , "nvdimm@lists.linux.dev" , "linux-kernel@vger.kernel.org" , "linux-xfs@vger.kernel.org" Subject: Re: [PATCH 4/6] dm,dax,pmem: prepare dax_copy_to/from_iter() APIs with DAXDEV_F_RECOVERY Message-ID: References: <20211021001059.438843-1-jane.chu@oracle.com> <20211021001059.438843-5-jane.chu@oracle.com> <325baeaf-54f6-dea0-ed2b-6be5a2ec47db@oracle.com> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <325baeaf-54f6-dea0-ed2b-6be5a2ec47db@oracle.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Fri, Oct 22, 2021 at 12:49:15AM +0000, Jane Chu wrote: > I've looked through your "futher decouple DAX from block devices" series > and likes the use of xarray in place of the host hash list. > Which upstream version is the series based upon? > If it's based on your development repo, I'd be happy to take a clone > and rebase my patches on yours if you provide a link. Please let me > know the best way to cooperate. It is based on linux-next from when it was posted. A git tree is here: http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/dax-block-cleanup > That said, I'm unclear at what you're trying to suggest with respect > to the 'DAXDEV_F_RECOVERY' flag. The flag came from upper dax-fs > call stack to the dm target layer, and the dm targets are equipped > with handling pmem driver specific task, so it appears that the flag > would need to be passed down to the native pmem layer, right? > Am I totally missing your point? We'll need to pass it through (assuming we want to keep supporting dm, see the recent discussion with Dan). FYI, here is a sketch where I'd like to move to, but this isn't properly tested yet: http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/dax-devirtualize To support something like DAXDEV_F_RECOVERYwe'd need a separate dax_operations methods. Which to me suggest it probably should be a different operation (fallocate / ioctl / etc) as Darrick did earlier.