From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f70.google.com (mail-wm0-f70.google.com [74.125.82.70]) by kanga.kvack.org (Postfix) with ESMTP id 9C36F440846 for ; Thu, 24 Aug 2017 12:11:54 -0400 (EDT) Received: by mail-wm0-f70.google.com with SMTP id n197so1390752wmg.2 for ; Thu, 24 Aug 2017 09:11:54 -0700 (PDT) Received: from newverein.lst.de (verein.lst.de. [213.95.11.211]) by mx.google.com with ESMTPS id t13si3611278wrg.41.2017.08.24.09.11.53 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 24 Aug 2017 09:11:53 -0700 (PDT) Date: Thu, 24 Aug 2017 18:11:52 +0200 From: Christoph Hellwig Subject: Re: [PATCH v6 4/5] fs, xfs: introduce MAP_DIRECT for creating block-map-atomic file ranges Message-ID: <20170824161152.GB27591@lst.de> References: <150353211413.5039.5228914877418362329.stgit@dwillia2-desk3.amr.corp.intel.com> <150353213655.5039.7662200155640827407.stgit@dwillia2-desk3.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <150353213655.5039.7662200155640827407.stgit@dwillia2-desk3.amr.corp.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Dan Williams Cc: akpm@linux-foundation.org, Jan Kara , "Darrick J. Wong" , linux-api@vger.kernel.org, linux-nvdimm@lists.01.org, Dave Chinner , linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Jeff Moyer , Alexander Viro , luto@kernel.org, linux-fsdevel@vger.kernel.org, Ross Zwisler , Christoph Hellwig I still can't make any sense of this description. What is an external agent? Userspace obviously can't ever see a change in the extent map, so it can't be meant. It would help a lot if you could come up with a concrete user for this, including example code. -- 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