From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o153eIAW108469 for ; Thu, 4 Feb 2010 21:40:18 -0600 Received: from mail.sandeen.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 445661CA5A70 for ; Thu, 4 Feb 2010 19:41:27 -0800 (PST) Received: from mail.sandeen.net (64-131-60-146.usfamily.net [64.131.60.146]) by cuda.sgi.com with ESMTP id 03voz1jwDRmyac2I for ; Thu, 04 Feb 2010 19:41:27 -0800 (PST) Message-ID: <4B6B9366.6020600@sandeen.net> Date: Thu, 04 Feb 2010 21:41:26 -0600 From: Eric Sandeen MIME-Version: 1.0 Subject: Re: [PATCH v2] mkfs.xfs fix detection of empty devices References: <4B6AF6FC.6030101@redhat.com> <20100204194000.GA7229@infradead.org> <20100204221822.GA26670@infradead.org> In-Reply-To: <20100204221822.GA26670@infradead.org> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Christoph Hellwig Cc: Jim Meyering , Eric Sandeen , xfs mailing list Christoph Hellwig wrote: > We currently fail to detect that a device does indeed not contain any > signature and we are indeed fine to proceed with it due to mishandling > the return value of blkid_do_fullprobe. Fix that up and add some > better diagnostics of the blkid detection. > > from RH bugzilla https://bugzilla.redhat.com/show_bug.cgi?id=561870 > > # dd if=/dev/zero of=k bs=1MB count=2 seek=20; mkfs.xfs k > # mkfs.xfs: probe of k failed, cannot detect existing filesystem. > # mkfs.xfs: Use the -f option to force overwrite > > Signed-off-by: Christoph Hellwig we discussed keeping the 0-size check until libblkid copes better; also the absense of ret = !ret looks more readable, thanks. Reviewed-by: Eric Sandeen > Index: xfsprogs-dev/mkfs/xfs_mkfs.c > =================================================================== > --- xfsprogs-dev.orig/mkfs/xfs_mkfs.c 2010-02-04 20:30:26.000000000 +0000 > +++ xfsprogs-dev/mkfs/xfs_mkfs.c 2010-02-04 20:43:41.000000000 +0000 > @@ -322,24 +322,40 @@ check_overwrite( > if (!pr) > goto out; > > - if (blkid_probe_enable_partitions(pr, 1)) > + ret = blkid_probe_enable_partitions(pr, 1); > + if (ret < 0) > goto out; > > - if (blkid_do_fullprobe(pr)) > + ret = blkid_do_fullprobe(pr); > + if (ret < 0) > goto out; > > - ret = 0; > + /* > + * Blkid returns 1 for nothing found and 0 when it finds a signature, > + * but we want the exact opposite, so reverse the return value here. > + * > + * In addition print some useful diagnostics about what actually is > + * on the device. > + */ > + if (ret) { > + ret = 0; > + goto out; > + } > + > if (!blkid_probe_lookup_value(pr, "TYPE", &type, NULL)) { > fprintf(stderr, > _("%s: %s appears to contain an existing " > "filesystem (%s).\n"), progname, device, type); > - ret = 1; > } else if (!blkid_probe_lookup_value(pr, "PTTYPE", &type, NULL)) { > fprintf(stderr, > _("%s: %s appears to contain a partition " > "table (%s).\n"), progname, device, type); > - ret = 1; > + } else { > + fprintf(stderr, > + _("%s: %s appears to contain something weird " > + "according to blkid\n"), progname, device); > } > + ret = 1; > > out: > if (pr) > > _______________________________________________ > xfs mailing list > xfs@oss.sgi.com > http://oss.sgi.com/mailman/listinfo/xfs > _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs