Return-Path: linux-nfs-owner@vger.kernel.org Received: from verein.lst.de ([213.95.11.211]:35217 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754303AbaHGMKz (ORCPT ); Thu, 7 Aug 2014 08:10:55 -0400 Date: Thu, 7 Aug 2014 14:10:52 +0200 From: Christoph Hellwig To: Peng Tao Cc: Christoph Hellwig , Trond Myklebust , linuxnfs , "faibish, sorin" Subject: Re: [PATCH 08/17] pnfs/blocklayout: reject pnfs blocksize larger than page size Message-ID: <20140807121052.GA5678@lst.de> References: <1407396229-4785-1-git-send-email-hch@lst.de> <1407396229-4785-9-git-send-email-hch@lst.de> <20140807112537.GA3437@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, Aug 07, 2014 at 07:51:57PM +0800, Peng Tao wrote: > Is it bl_find_get_zeroing_page() you are concerning about? That's the primary culprit. If you want to do the read-modify write cycle properly you'll have to do it at the time the invalid extent is read, not written. Take a look at my patch to add a flag to do that in page 5, although it would be a lot more involved to do it for large pnfs block sizes. Given that the code never really fully worked beforehand I'm not tempted to come up with that myself, though.