Return-Path: linux-nfs-owner@vger.kernel.org Received: from bombadil.infradead.org ([198.137.202.9]:42619 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755447Ab3J2NHW (ORCPT ); Tue, 29 Oct 2013 09:07:22 -0400 Date: Tue, 29 Oct 2013 06:07:21 -0700 From: Christoph Hellwig To: Anna Schumaker Cc: Christoph Hellwig , bfields@fieldses.org, linux-nfs@vger.kernel.org Subject: Re: [PATCH 4/4] NFSD: Implement SEEK Message-ID: <20131029130721.GA32094@infradead.org> References: <1382972247-1108-1-git-send-email-bjschuma@netapp.com> <1382972247-1108-5-git-send-email-bjschuma@netapp.com> <20131029073558.GA10889@infradead.org> <526FB180.1060003@netapp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <526FB180.1060003@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Tue, Oct 29, 2013 at 09:00:48AM -0400, Anna Schumaker wrote: > 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... You can have preallocated space, which behaves like a hole in that reads return zeroes. As far as SEEK_DATA/SEEK_HOLE is concerned we tend to treat them as holes when we can as that's what the users expect. Note that at least the pnfs block rfc has a special state representing this kind of preallocated space.