From 34d7f603b93be0ac38c2464219f5a2795d76c8ee Mon Sep 17 00:00:00 2001 From: Jie Liu Date: Thu, 2 May 2013 19:27:53 +0800 Subject: [PATCH] xfs: Don't keep silent if sunit/swidth can not be changed via mount As per the mount man page, sunit and swidth can be changed via mount options. For XFS, on the face of it, those options seems works if the specified alignments is properly, e.g. # mount -o sunit=4096,swidth=8192 /dev/sdb1 /mnt # mount | grep sdb1 /dev/sdb1 on /mnt type xfs (rw,sunit=4096,swidth=8192) However, neither sunit nor swidth is shown from the xfs_info output. # xfs_info /mnt meta-data=/dev/sdb1 isize=256 agcount=4, agsize=262144 blks = sectsz=512 attr=2 data = bsize=4096 blocks=1048576, imaxpct=25 = sunit=0 swidth=0 blks ^^^^^^^^^^^^^^^^^^^^^^^^^^ naming =version 2 bsize=4096 ascii-ci=0 log =internal bsize=4096 blocks=2560, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 The reason is that the alignment can only be changed if the relevant super block is already configured with alignments, otherwise, the given value is silently ignored. With this fix, the attempt to mount a storage without strip alignment setup on a super block will get an error with a warning in syslog to indicate the true cause, e.g. # mount -o sunit=4096,swidth=8192 /dev/sdb1 /mnt mount: wrong fs type, bad option, bad superblock on /dev/sdb1, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so ....... XFS (sdb1): cannot change alignment: superblock does not support data alignment Signed-off-by: Jie Liu Cc: Mark Tinguely Cc: Dave Chinner Reviewed-by: Mark Tinguely Signed-off-by: Ben Myers --- fs/xfs/xfs_mount.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index e8e310c05097..6a19434eba2a 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -1039,6 +1039,10 @@ xfs_update_alignment(xfs_mount_t *mp) sbp->sb_width = mp->m_swidth; mp->m_update_flags |= XFS_SB_WIDTH; } + } else { + xfs_warn(mp, + "cannot change alignment: superblock does not support data alignment"); + return XFS_ERROR(EINVAL); } } else if ((mp->m_flags & XFS_MOUNT_NOALIGN) != XFS_MOUNT_NOALIGN && xfs_sb_version_hasdalign(&mp->m_sb)) { -- 2.20.1