From: Andreas Dilger Subject: Re: [PATCH] e2fsprogs: misc: Remove broken whole device check Date: Mon, 1 Jun 2015 16:56:45 -0600 Message-ID: <74D84728-EFE7-4FF0-A99C-20F1F18EF8DF@dilger.ca> References: <1433198362-86983-1-git-send-email-ryao@gentoo.org> Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2098\)) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT Cc: linux-ext4@vger.kernel.org, Theodore Ts'o , Richard Yao To: Richard Yao Return-path: Received: from mail-pa0-f46.google.com ([209.85.220.46]:34655 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753602AbbFAW4s convert rfc822-to-8bit (ORCPT ); Mon, 1 Jun 2015 18:56:48 -0400 Received: by payr10 with SMTP id r10so36458828pay.1 for ; Mon, 01 Jun 2015 15:56:48 -0700 (PDT) In-Reply-To: <1433198362-86983-1-git-send-email-ryao@gentoo.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Jun 1, 2015, at 4:39 PM, Richard Yao wrote: > > From: Richard Yao > > Modern Linux major/minor numbering on block devices no longer conform to > the divisible by 64 rule for minor numbering. On my development system, > the correct number is 16. Consequently, this applies only to every 4th > drive on a modern system, which is inconsistent. That caused the > following bug to be filed against Flocker: > > https://clusterhq.atlassian.net/browse/FLOC-2041 > > We could unconditionally pass -F to override this check whenever it > triggers, but that it would also override the libblkid check that > determines whether there are existing partitions, logical volumes or > filesystems on the disk, which seems unwise. > > I propose that this check be removed because passing a whole disk to > mke2fs is a valid use case and given how long this has been broken, > users are already accustomed to the behavior where -F is not necessary > to format a whole disk as ext4. I totally agree - we've been overriding this check for years, and I'm glad to see it go. We have other mechanisms today to avoid users accidentally formatting the wrong device (O_EXCL, check for existing filesystems in interactive mode, etc.) Reviewed-by: Andreas Dilger > Signed-off-by: Richard Yao > --- > misc/plausible.c | 32 -------------------------------- > 1 file changed, 32 deletions(-) > > diff --git a/misc/plausible.c b/misc/plausible.c > index 1848a26..97492b9 100644 > --- a/misc/plausible.c > +++ b/misc/plausible.c > @@ -18,9 +18,6 @@ > #include "config.h" > #include > #include > -#ifdef HAVE_LINUX_MAJOR_H > -#include > -#endif > #include > #ifdef HAVE_SYS_STAT_H > #include > @@ -265,35 +262,6 @@ int check_plausibility(const char *device, int flags, int *ret_is_dev) > if (ret >= 0) > return ret; > > -#ifdef HAVE_LINUX_MAJOR_H > -#ifndef MAJOR > -#define MAJOR(dev) ((dev)>>8) > -#define MINOR(dev) ((dev) & 0xff) > -#endif > -#ifndef SCSI_BLK_MAJOR > -#ifdef SCSI_DISK0_MAJOR > -#ifdef SCSI_DISK8_MAJOR > -#define SCSI_DISK_MAJOR(M) ((M) == SCSI_DISK0_MAJOR || \ > - ((M) >= SCSI_DISK1_MAJOR && (M) <= SCSI_DISK7_MAJOR) || \ > - ((M) >= SCSI_DISK8_MAJOR && (M) <= SCSI_DISK15_MAJOR)) > -#else > -#define SCSI_DISK_MAJOR(M) ((M) == SCSI_DISK0_MAJOR || \ > - ((M) >= SCSI_DISK1_MAJOR && (M) <= SCSI_DISK7_MAJOR)) > -#endif /* defined(SCSI_DISK8_MAJOR) */ > -#define SCSI_BLK_MAJOR(M) (SCSI_DISK_MAJOR((M)) || (M) == SCSI_CDROM_MAJOR) > -#else > -#define SCSI_BLK_MAJOR(M) ((M) == SCSI_DISK_MAJOR || (M) == SCSI_CDROM_MAJOR) > -#endif /* defined(SCSI_DISK0_MAJOR) */ > -#endif /* defined(SCSI_BLK_MAJOR) */ > - if (((MAJOR(s.st_rdev) == HD_MAJOR && > - MINOR(s.st_rdev)%64 == 0) || > - (SCSI_BLK_MAJOR(MAJOR(s.st_rdev)) && > - MINOR(s.st_rdev)%16 == 0))) { > - printf(_("%s is entire device, not just one partition!\n"), > - device); > - return 0; > - } > -#endif > return 1; > } > > -- > 2.3.6 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Cheers, Andreas