From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f72.google.com (mail-pa0-f72.google.com [209.85.220.72]) by kanga.kvack.org (Postfix) with ESMTP id 188E46B0069 for ; Sat, 10 Sep 2016 03:50:14 -0400 (EDT) Received: by mail-pa0-f72.google.com with SMTP id vp2so216188362pab.3 for ; Sat, 10 Sep 2016 00:50:14 -0700 (PDT) Received: from NAM03-CO1-obe.outbound.protection.outlook.com (mail-co1nam03on0113.outbound.protection.outlook.com. [104.47.40.113]) by mx.google.com with ESMTPS id p20si4051758pag.161.2016.09.10.00.50.13 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sat, 10 Sep 2016 00:50:13 -0700 (PDT) From: Matthew Wilcox Subject: RE: [PATCH v2 2/9] ext2: tell DAX the size of allocation holes Date: Sat, 10 Sep 2016 07:50:09 +0000 Message-ID: References: <20160823220419.11717-1-ross.zwisler@linux.intel.com> <20160823220419.11717-3-ross.zwisler@linux.intel.com> <20160825075728.GA11235@infradead.org> <20160826212934.GA11265@linux.intel.com> <20160829074116.GA16491@infradead.org> <20160829125741.cdnbb2uaditcmnw2@thunk.org> <20160909164808.GC18554@linux.intel.com> <20160910073151.GB5295@infradead.org> In-Reply-To: <20160910073151.GB5295@infradead.org> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Hellwig , Dan Williams Cc: Ross Zwisler , Theodore Ts'o , "linux-kernel@vger.kernel.org" , Andrew Morton , "linux-nvdimm@ml01.01.org" , Dave Chinner , "linux-mm@kvack.org" , Andreas Dilger , Alexander Viro , Jan Kara , "linux-fsdevel@vger.kernel.org" , "linux-ext4@vger.kernel.org" From: Christoph Hellwig [mailto:hch@infradead.org] > On Fri, Sep 09, 2016 at 03:34:43PM -0700, Dan Williams wrote: > > I agree with you that continuing to touch ext2 is not a good idea, but > > I'm not yet convinced that now is the time to go do dax-2.0 when we > > haven't finished shipping dax-1.0. >=20 > I've mentioned this before, but I'd like to repeat it. With all the work= reqwuired > in the file system I would prefer to drop DAX support in ext2 (and if peo= ple > really cry for it reinstate the trivial old xip support). That allegedly trivial old xip support was horrendously broken. And, er, i= t used an aop which you seem implacably opposed to in your earlier email. And that was t= ruly a disgusting one from a layering point of view. Let me remind you: -=A0=A0=A0=A0=A0=A0=A0int=A0(*get_xip_mem)(struct=A0address_space=A0*,=A0pg= off_t,=A0int, -=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0void= =A0**,=A0unsigned=A0long=A0*); That void ** was an 'out' parameter to store a kernel address for the memor= y. The unsigned long * was also an 'out' parameter to store the PFN for the memory= . The 'int' was actually a Boolean for whether to create or not, but you'd actual= ly have to go look at the implementation to find that out; the documentation never sai= d it. A real dog's breakfast of an API. -- 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