From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Mon, 18 Feb 2008 15:32:39 -0800 (PST) Received: from larry.melbourne.sgi.com (larry.melbourne.sgi.com [134.14.52.130]) by oss.sgi.com (8.12.11.20060308/8.12.11/SuSE Linux 0.7) with SMTP id m1INWVxT004618 for ; Mon, 18 Feb 2008 15:32:35 -0800 Date: Tue, 19 Feb 2008 10:32:51 +1100 From: David Chinner Subject: [patch] Don't change ctime in truncate is size does not change Message-ID: <20080218233251.GV155407@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: xfs-dev Cc: xfs-oss XFS changes the c/mtime of an inode when truncating it to the same size. The c/mtime is only supposed to change if the size is changed. Not to be confused with ftruncate, where the c/mtime is supposed to be changed even if the size is not changed. The Linux VFS encodes this semantic difference in the flags it sends down to ->setattr, which XFS currently ignores. We need to make XFS pay attention to the VFS flags and hence Do The Right Thing. Signed-off-by: Dave Chinner --- fs/xfs/xfs_vnodeops.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) Index: 2.6.x-xfs-new/fs/xfs/xfs_vnodeops.c =================================================================== --- 2.6.x-xfs-new.orig/fs/xfs/xfs_vnodeops.c 2008-01-25 16:03:23.654971763 +1100 +++ 2.6.x-xfs-new/fs/xfs/xfs_vnodeops.c 2008-01-25 16:10:30.875397129 +1100 @@ -634,6 +634,15 @@ xfs_setattr( * Truncate file. Must have write permission and not be a directory. */ if (mask & XFS_AT_SIZE) { + /* + * Only change the c/mtime if we are changing the size + * or we are explicitly asked to change it. This handles + * the semantic difference between truncate() and ftruncate() + * as implemented in the VFS. + */ + if (vap->va_size != ip->i_size || mask & XFS_AT_CTIME) + timeflags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG; + if (vap->va_size > ip->i_size) { xfs_igrow_finish(tp, ip, vap->va_size, !(flags & ATTR_DMI)); @@ -662,10 +671,6 @@ xfs_setattr( */ xfs_iflags_set(ip, XFS_ITRUNCATED); } - /* - * Have to do this even if the file's size doesn't change. - */ - timeflags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG; } /*