From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752135AbeERH0f (ORCPT ); Fri, 18 May 2018 03:26:35 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:34218 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751156AbeERH0d (ORCPT ); Fri, 18 May 2018 03:26:33 -0400 Date: Fri, 18 May 2018 00:26:31 -0700 From: Christoph Hellwig To: longli@microsoft.com Cc: Steve French , linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org Subject: Re: [RFC PATCH 09/09] Introduce cache=rdma moutning option Message-ID: <20180518072631.GA19250@infradead.org> References: <20180518002214.5657-1-longli@linuxonhyperv.com> <20180518002214.5657-10-longli@linuxonhyperv.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180518002214.5657-10-longli@linuxonhyperv.com> User-Agent: Mutt/1.9.2 (2017-12-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 17, 2018 at 05:22:14PM -0700, Long Li wrote: > From: Long Li > > When cache=rdma is enabled on mount options, CIFS do not allocate internal data > buffer pages for I/O, data is read/writen directly to user memory via RDMA. I don't think this should be an option. For direct I/O without signing or encryption CIFS should always use get_user_pages, with or without RDMA.