From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH 6/8] nowait aio: ext4 Date: Mon, 10 Apr 2017 07:39:43 -0700 Message-ID: <20170410143943.GA2930@infradead.org> References: <20170403185307.6243-1-rgoldwyn@suse.de> <20170403185307.6243-7-rgoldwyn@suse.de> <20170404075853.GB28522@quack2.suse.cz> <20170404084122.GA10252@infradead.org> <20170410074539.GA18250@infradead.org> <20170410123750.GE3224@quack2.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20170410123750.GE3224@quack2.suse.cz> Sender: linux-fsdevel-owner@vger.kernel.org To: Jan Kara Cc: Christoph Hellwig , Goldwyn Rodrigues , linux-fsdevel@vger.kernel.org, jack@suse.com, linux-block@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, sagi@grimberg.me, avi@scylladb.com, axboe@kernel.dk, linux-api@vger.kernel.org, willy@infradead.org, tom.leiming@gmail.com, Goldwyn Rodrigues List-Id: linux-api@vger.kernel.org On Mon, Apr 10, 2017 at 02:37:50PM +0200, Jan Kara wrote: > I don't understand here. Do you want that all filesystems support NOWAIT > direct IO? No. Per-file_system_type is way to coarse grained. All feature flag needs to be per-file_operation at least for cases like ext4 with our without extents (or journal) XFS v4 vs v5, different NFS versions, etc. For RWF_* each file operation simply declares if the feature is supported not by rejecting unknown ones. FIEMAP does the same as do a few other interfaces.