From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id 09BF07F5D for ; Thu, 18 Jun 2015 12:01:31 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay3.corp.sgi.com (Postfix) with ESMTP id 9A378AC001 for ; Thu, 18 Jun 2015 10:01:27 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id Gdk1vmrpWUAl3zXH (version=TLSv1 cipher=AES256-SHA bits=256 verify=NO) for ; Thu, 18 Jun 2015 10:01:26 -0700 (PDT) Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (Postfix) with ESMTPS id 5B88FBACCC for ; Thu, 18 Jun 2015 17:01:26 +0000 (UTC) Message-ID: <5582F962.2090400@redhat.com> Date: Thu, 18 Jun 2015 12:01:22 -0500 From: Eric Sandeen MIME-Version: 1.0 Subject: [PATCH] xfs_repair: refuse to unset lazycount on V5 filesystems 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 Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: xfs-oss Cc: "Richard W.M. Jones" Running "xfs_admin -c 0" on a V5 fs has unfortunate results. Before: versionnum [0xbca5+0x18a] = ... LAZYSBCOUNT,PROJID32BIT,CRC, ... After: versionnum [0xbca5+0x188] = ... LAZYSBCOUNT,PROJID32BIT,CRC, ... The on-disk feature bit is in fact changed, but xfs_db reports that the feature is still present. This is because xfs_sb_version_haslazysbcount() ignores the feature bit, and always reports that the lazy-count feature is present on a V5 fs. i.e. the intent is that this feature is not optional on a V5 fs, yet we still flip the bit on disk when asked. Not good. So, document this, and error out if the user tries to disable lazy-count on a version 5 filesystem. Reported-by: Richard W.M. Jones Signed-off-by: Eric Sandeen --- (hm, xfs_repair should probably also turn the bit back on, if it's off on V5? I'll save that for another patch.) diff --git a/man/man8/xfs_admin.8 b/man/man8/xfs_admin.8 index b393d74..0968196 100644 --- a/man/man8/xfs_admin.8 +++ b/man/man8/xfs_admin.8 @@ -62,6 +62,10 @@ Print the current filesystem UUID (Universally Unique IDentifier). .TP .BR "\-c 0" | 1 Enable (1) or disable (0) lazy-counters in the filesystem. +.IP +Lazy-counters may not be disabled on Version 5 superblock filesystems +(i.e. those with metadata CRCs enabled). +.IP This operation may take quite a bit of time on large filesystems as the entire filesystem needs to be scanned when this option is changed. .IP diff --git a/repair/phase1.c b/repair/phase1.c index ec75ada..9e7011d 100644 --- a/repair/phase1.c +++ b/repair/phase1.c @@ -121,8 +121,12 @@ phase1(xfs_mount_t *mp) sb->sb_bad_features2 |= XFS_SB_VERSION2_LAZYSBCOUNTBIT; primary_sb_modified = 1; printf(_("Enabling lazy-counters\n")); - } else - if (!lazy_count && xfs_sb_version_haslazysbcount(sb)) { + } else if (!lazy_count && xfs_sb_version_haslazysbcount(sb)) { + if (XFS_SB_VERSION_NUM(sb) == XFS_SB_VERSION_5) { + printf( +_("Cannot disable lazy-counters on V5 fs\n")); + exit(1); + } sb->sb_features2 &= ~XFS_SB_VERSION2_LAZYSBCOUNTBIT; sb->sb_bad_features2 &= ~XFS_SB_VERSION2_LAZYSBCOUNTBIT; printf(_("Disabling lazy-counters\n")); _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs