From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [LSF/MM TOPIC] Future direction of DAX Date: Mon, 16 Jan 2017 23:57:35 -0800 Message-ID: <20170117075735.GB19654@infradead.org> References: <20170114002008.GA25379@linux.intel.com> <20170114082621.GC10498@birch.djwong.org> <20170117015033.GD10498@birch.djwong.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20170117015033.GD10498-PTl6brltDGh4DFYR7WNSRA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-nvdimm-bounces-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org Sender: "Linux-nvdimm" To: "Darrick J. Wong" Cc: linux-nvdimm-y27Ovi1pjclAfugRpC6u6w@public.gmane.org, linux-block-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, lsf-pc-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: linux-nvdimm@lists.01.org On Mon, Jan 16, 2017 at 05:50:33PM -0800, Darrick J. Wong wrote: > I wouldn't consider it a barrier in general (since ext4 also prints > EXPERIMENTAL warnings for DAX), merely one for XFS. I don't even think > it's that big of a hurdle -- afaict XFS ought to be able to achieve this > by modifying iomap_begin to allocate new pmem blocks, memcpy the > contents, and update the memory mappings. I think. Yes, and I have a working prototype for that. I'm just way to busy with lots of bugfixing at the moment but I plan to get to it in this merge window. I also agree that we can't mark a feature as fully supported until it doesn't conflict with other features. And I'm not going to get start on the PMEM_IMMUTABLE bullshit, please don't even go there folks, it's a dead end. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Mon, 16 Jan 2017 23:57:35 -0800 From: Christoph Hellwig To: "Darrick J. Wong" Cc: Jeff Moyer , Ross Zwisler , lsf-pc@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-nvdimm@ml01.01.org, linux-block@vger.kernel.org, linux-mm@kvack.org Subject: Re: [LSF/MM TOPIC] Future direction of DAX Message-ID: <20170117075735.GB19654@infradead.org> References: <20170114002008.GA25379@linux.intel.com> <20170114082621.GC10498@birch.djwong.org> <20170117015033.GD10498@birch.djwong.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20170117015033.GD10498@birch.djwong.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Mon, Jan 16, 2017 at 05:50:33PM -0800, Darrick J. Wong wrote: > I wouldn't consider it a barrier in general (since ext4 also prints > EXPERIMENTAL warnings for DAX), merely one for XFS. I don't even think > it's that big of a hurdle -- afaict XFS ought to be able to achieve this > by modifying iomap_begin to allocate new pmem blocks, memcpy the > contents, and update the memory mappings. I think. Yes, and I have a working prototype for that. I'm just way to busy with lots of bugfixing at the moment but I plan to get to it in this merge window. I also agree that we can't mark a feature as fully supported until it doesn't conflict with other features. And I'm not going to get start on the PMEM_IMMUTABLE bullshit, please don't even go there folks, it's a dead end. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Mon, 16 Jan 2017 23:57:35 -0800 From: Christoph Hellwig To: "Darrick J. Wong" Cc: Jeff Moyer , Ross Zwisler , lsf-pc@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-nvdimm@ml01.01.org, linux-block@vger.kernel.org, linux-mm@kvack.org Subject: Re: [LSF/MM TOPIC] Future direction of DAX Message-ID: <20170117075735.GB19654@infradead.org> References: <20170114002008.GA25379@linux.intel.com> <20170114082621.GC10498@birch.djwong.org> <20170117015033.GD10498@birch.djwong.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170117015033.GD10498@birch.djwong.org> Sender: owner-linux-mm@kvack.org List-ID: On Mon, Jan 16, 2017 at 05:50:33PM -0800, Darrick J. Wong wrote: > I wouldn't consider it a barrier in general (since ext4 also prints > EXPERIMENTAL warnings for DAX), merely one for XFS. I don't even think > it's that big of a hurdle -- afaict XFS ought to be able to achieve this > by modifying iomap_begin to allocate new pmem blocks, memcpy the > contents, and update the memory mappings. I think. Yes, and I have a working prototype for that. I'm just way to busy with lots of bugfixing at the moment but I plan to get to it in this merge window. I also agree that we can't mark a feature as fully supported until it doesn't conflict with other features. And I'm not going to get start on the PMEM_IMMUTABLE bullshit, please don't even go there folks, it's a dead end. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org