Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx11.netapp.com ([216.240.18.76]:20137 "EHLO mx11.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752823Ab3J2NAv (ORCPT ); Tue, 29 Oct 2013 09:00:51 -0400 Message-ID: <526FB180.1060003@netapp.com> Date: Tue, 29 Oct 2013 09:00:48 -0400 From: Anna Schumaker MIME-Version: 1.0 To: Christoph Hellwig CC: , Subject: Re: [PATCH 4/4] NFSD: Implement SEEK References: <1382972247-1108-1-git-send-email-bjschuma@netapp.com> <1382972247-1108-5-git-send-email-bjschuma@netapp.com> <20131029073558.GA10889@infradead.org> In-Reply-To: <20131029073558.GA10889@infradead.org> Content-Type: text/plain; charset="UTF-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: On Tue 29 Oct 2013 03:35:58 AM EDT, Christoph Hellwig wrote: > On Mon, Oct 28, 2013 at 10:57:26AM -0400, Anna Schumaker wrote: >> This patch adds in the SEEK operation used by clients doing an llseek on >> a file to find either hole or data sections in a file. I'm faking the >> "allocated" status right now, since I haven't quite figured out how to >> tell if a range is allocated on disk yet. >> >> This patch is missing correctly determining the "allocated" status of >> the HOLE / DATA range. I expect I'll need to learn all about how fiemap >> works before properly setting these values. > > What is the definition of allocated in this context? Specificly how > does it different from meaning of allocated as used by SEEK_DATA? From what I can tell, I think the allocated flag will just tell the clients if all the blocks exist on disk or not. Is there a way to have a hole with allocated blocks? Or maybe it's supposed to represent partially allocated blocks? I checked the draft, and it doesn't actually say what they expect allocated to represent... > > Going out to fiemap is something we should absolutely avoid. >