Return-Path: Received: from bombadil.infradead.org ([198.137.202.9]:56116 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752136AbcFVQmq (ORCPT ); Wed, 22 Jun 2016 12:42:46 -0400 Date: Wed, 22 Jun 2016 09:42:40 -0700 From: Christoph Hellwig To: Trond Myklebust Cc: linux-nfs@vger.kernel.org Subject: Re: [PATCH v2 11/12] NFS: Remove inode->i_dio_count from the NFS O_DIRECT code Message-ID: <20160622164240.GA9176@infradead.org> References: <1466544893-12058-2-git-send-email-trond.myklebust@primarydata.com> <1466544893-12058-3-git-send-email-trond.myklebust@primarydata.com> <1466544893-12058-4-git-send-email-trond.myklebust@primarydata.com> <1466544893-12058-5-git-send-email-trond.myklebust@primarydata.com> <1466544893-12058-6-git-send-email-trond.myklebust@primarydata.com> <1466544893-12058-7-git-send-email-trond.myklebust@primarydata.com> <1466544893-12058-8-git-send-email-trond.myklebust@primarydata.com> <1466544893-12058-9-git-send-email-trond.myklebust@primarydata.com> <1466544893-12058-10-git-send-email-trond.myklebust@primarydata.com> <1466544893-12058-11-git-send-email-trond.myklebust@primarydata.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1466544893-12058-11-git-send-email-trond.myklebust@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Tue, Jun 21, 2016 at 05:34:52PM -0400, Trond Myklebust wrote: > Now that we can serialise O_DIRECT and write/truncate using the > inode->i_rwsem, we no longer need inode->i_dio_count. For the AIO case that's not true, we can't hold i_rwsem until aio completes. So for something that does block allocations we'll need something like i_dio_count still. This probably includes the block / scsi layout code.