From: Josef Bacik Subject: Re: [PATCH 4/6] Ext4: fail if we try to use hole punch Date: Tue, 16 Nov 2010 07:50:16 -0500 Message-ID: <20101116125016.GA31957@dhcp231-156.rdu.redhat.com> References: <1289840723-3056-1-git-send-email-josef@redhat.com> <1289840723-3056-5-git-send-email-josef@redhat.com> <4CE2783F.1020004@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Josef Bacik , david@fromorbit.com, linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, xfs@oss.sgi.com, cmm@us.ibm.com, cluster-devel@redhat.com, ocfs2-devel@oss.oracle.com To: Avi Kivity Return-path: Content-Disposition: inline In-Reply-To: <4CE2783F.1020004@redhat.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Tue, Nov 16, 2010 at 02:25:35PM +0200, Avi Kivity wrote: > On 11/15/2010 07:05 PM, Josef Bacik wrote: >> Ext4 doesn't have the ability to punch holes yet, so make sure we return >> EOPNOTSUPP if we try to use hole punching through fallocate. This support can >> be added later. Thanks, >> > > Instead of teaching filesystems to fail if they don't support the > capability, why don't supporting filesystems say so, allowing the fail > code to be in common code? > There is no simple way to test if a filesystem supports hole punching or not so the check has to be done per fs. Thanks, Josef