[PATCH] fs: push sync_filesystem() down to the file system's remount_fs()

Theodore Ts'o
2014-03-13T14:22:11Z

Previously, the no-op "mount -o mount /dev/xxx" operation when the
file system is already mounted read-write causes an implied,
unconditional syncfs(). This seems pretty stupid, and it's certainly
documented or guaraunteed to do this, nor is it particularly useful,
except in the case where the file system was mounted rw and is getting
remounted read-only.

However, it's possible that there might be some file systems that are
actually depending on this behavior. In most file systems, it's
probably fine to only call sync_filesystem() when transitioning from
read-write to read-only, and there are some file systems where this is
not needed at all (for example, for a pseudo-filesystem or something
like romfs).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: linux-fsdevel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: Jan Kara <jack@suse.cz>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Anders Larsen <al@alarsen.net>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: Petr Vandrovec <petr@vandrovec.name>
Cc: xfs@oss.sgi.com
Cc: linux-btrfs@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: codalist@coda.cs.cmu.edu
Cc: linux-ext4@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: fuse-devel@lists.sourceforge.net
Cc: cluster-devel@redhat.com
Cc: linux-mtd@lists.infradead.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: linux-nfs@vger.kernel.org
Cc: linux-nilfs@vger.kernel.org
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Cc: reiserfs-devel@vger.kernel.org
---
fs/adfs/super.c | 1 +
fs/affs/super.c | 1 +
fs/befs/linuxvfs.c | 1 +
fs/btrfs/super.c | 1 +
fs/cifs/cifsfs.c | 1 +
fs/coda/inode.c | 1 +
fs/cramfs/inode.c | 1 +
fs/debugfs/inode.c | 1 +
fs/devpts/inode.c | 1 +
fs/efs/super.c | 1 +
fs/ext2/super.c | 1 +
fs/ext3/super.c | 2 ++
fs/ext4/super.c | 2 ++
fs/f2fs/super.c | 2 ++
fs/fat/inode.c | 2 ++
fs/freevxfs/vxfs_super.c | 1 +
fs/fuse/inode.c | 1 +
fs/gfs2/super.c | 2 ++
fs/hfs/super.c | 1 +
fs/hfsplus/super.c | 1 +
fs/hpfs/super.c | 2 ++
fs/isofs/inode.c | 1 +
fs/jffs2/super.c | 1 +
fs/jfs/super.c | 1 +
fs/minix/inode.c | 1 +
fs/ncpfs/inode.c | 1 +
fs/nfs/super.c | 2 ++
fs/nilfs2/super.c | 1 +
fs/ntfs/super.c | 2 ++
fs/ocfs2/super.c | 2 ++
fs/openpromfs/inode.c | 1 +
fs/proc/root.c | 2 ++
fs/pstore/inode.c | 1 +
fs/qnx4/inode.c | 1 +
fs/qnx6/inode.c | 1 +
fs/reiserfs/super.c | 1 +
fs/romfs/super.c | 1 +
fs/squashfs/super.c | 1 +
fs/super.c | 2 --
fs/sysv/inode.c | 1 +
fs/ubifs/super.c | 1 +
fs/udf/super.c | 1 +
fs/ufs/super.c | 1 +
fs/xfs/xfs_super.c | 1 +
44 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/fs/adfs/super.c b/fs/adfs/super.c
index 7b3003c..952aeb0 100644
--- a/fs/adfs/super.c
+++ b/fs/adfs/super.c
@@ -212,6 +212,7 @@ static int parse_options(struct super_block *sb, char *options)

static int adfs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_NODIRATIME;
return parse_options(sb, data);
}
diff --git a/fs/affs/super.c b/fs/affs/super.c
index d098731..3074530 100644
--- a/fs/affs/super.c
+++ b/fs/affs/super.c
@@ -530,6 +530,7 @@ affs_remount(struct super_block *sb, int *flags, char *data)

pr_debug("AFFS: remount(flags=0x%x,opts=\"%s\")\n",*flags,data);

+ sync_filesystem(sb);
*flags |= MS_NODIRATIME;

memcpy(volume, sbi->s_volume, 32);
diff --git a/fs/befs/linuxvfs.c b/fs/befs/linuxvfs.c
index 845d2d6..56d70c8 100644
--- a/fs/befs/linuxvfs.c
+++ b/fs/befs/linuxvfs.c
@@ -913,6 +913,7 @@ befs_fill_super(struct super_block *sb, void *data, int silent)
static int
befs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
if (!(*flags & MS_RDONLY))
return -EINVAL;
return 0;
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 97cc241..00cd0c5 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1381,6 +1381,7 @@ static int btrfs_remount(struct super_block *sb, int *flags, char *data)
unsigned int old_metadata_ratio = fs_info->metadata_ratio;
int ret;

+ sync_filesystem(sb);
btrfs_remount_prepare(fs_info);

ret = btrfs_parse_options(root, data);
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 849f613..4942c94 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -541,6 +541,7 @@ static int cifs_show_stats(struct seq_file *s, struct dentry *root)

static int cifs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_NODIRATIME;
return 0;
}
diff --git a/fs/coda/inode.c b/fs/coda/inode.c
index 506de34..3f48000 100644
--- a/fs/coda/inode.c
+++ b/fs/coda/inode.c
@@ -96,6 +96,7 @@ void coda_destroy_inodecache(void)

static int coda_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_NOATIME;
return 0;
}
diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index 06610cf..a275911 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -244,6 +244,7 @@ static void cramfs_kill_sb(struct super_block *sb)

static int cramfs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_RDONLY;
return 0;
}
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 9c0444c..02928a9 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -218,6 +218,7 @@ static int debugfs_remount(struct super_block *sb, int *flags, char *data)
int err;
struct debugfs_fs_info *fsi = sb->s_fs_info;

+ sync_filesystem(sb);
err = debugfs_parse_options(data, &fsi->mount_opts);
if (err)
goto fail;
diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index a726b9f..c710380 100644
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -313,6 +313,7 @@ static int devpts_remount(struct super_block *sb, int *flags, char *data)
struct pts_fs_info *fsi = DEVPTS_SB(sb);
struct pts_mount_opts *opts = &fsi->mount_opts;

+ sync_filesystem(sb);
err = parse_mount_options(data, PARSE_REMOUNT, opts);

/*
diff --git a/fs/efs/super.c b/fs/efs/super.c
index 50215bb..103bbd8 100644
--- a/fs/efs/super.c
+++ b/fs/efs/super.c
@@ -114,6 +114,7 @@ static void destroy_inodecache(void)

static int efs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_RDONLY;
return 0;
}
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 20d6697..d260115 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -1254,6 +1254,7 @@ static int ext2_remount (struct super_block * sb, int * flags, char * data)
unsigned long old_sb_flags;
int err;

+ sync_filesystem(sb);
spin_lock(&sbi->s_lock);

/* Store the old options */
diff --git a/fs/ext3/super.c b/fs/ext3/super.c
index 37fd31e..95c6c5a 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -2649,6 +2649,8 @@ static int ext3_remount (struct super_block * sb, int * flags, char * data)
int i;
#endif

+ sync_filesystem(sb);
+
/* Store the original options */
old_sb_flags = sb->s_flags;
old_opts.s_mount_opt = sbi->s_mount_opt;
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index f5c13b8..aa3842f 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4767,6 +4767,8 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data)
#endif
char *orig_data = kstrdup(data, GFP_KERNEL);

+ sync_filesystem(sb);
+
/* Store the original options */
old_sb_flags = sb->s_flags;
old_opts.s_mount_opt = sbi->s_mount_opt;
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 1a85f83..856bdf9 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -568,6 +568,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
struct f2fs_mount_info org_mount_opt;
int err, active_logs;

+ sync_filesystem(sb);
+
/*
* Save the old mount options in case we
* need to restore them.
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 854b578..343e477 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -635,6 +635,8 @@ static int fat_remount(struct super_block *sb, int *flags, char *data)
struct msdos_sb_info *sbi = MSDOS_SB(sb);
*flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME);

+ sync_filesystem(sb);
+
/* make sure we update state on remount. */
new_rdonly = *flags & MS_RDONLY;
if (new_rdonly != (sb->s_flags & MS_RDONLY)) {
diff --git a/fs/freevxfs/vxfs_super.c b/fs/freevxfs/vxfs_super.c
index e37eb27..7ca8c75 100644
--- a/fs/freevxfs/vxfs_super.c
+++ b/fs/freevxfs/vxfs_super.c
@@ -124,6 +124,7 @@ vxfs_statfs(struct dentry *dentry, struct kstatfs *bufp)

static int vxfs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_RDONLY;
return 0;
}
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index d468643..ecdb255d 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -135,6 +135,7 @@ static void fuse_evict_inode(struct inode *inode)

static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
if (*flags & MS_MANDLOCK)
return -EINVAL;

diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 60f60f6..4c6dd50 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -1175,6 +1175,8 @@ static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
struct gfs2_tune *gt = &sdp->sd_tune;
int error;

+ sync_filesystem(sb);
+
spin_lock(&gt->gt_spin);
args.ar_commit = gt->gt_logd_secs;
args.ar_quota_quantum = gt->gt_quota_quantum;
diff --git a/fs/hfs/super.c b/fs/hfs/super.c
index 2d2039e..eee7206 100644
--- a/fs/hfs/super.c
+++ b/fs/hfs/super.c
@@ -112,6 +112,7 @@ static int hfs_statfs(struct dentry *dentry, struct kstatfs *buf)

static int hfs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_NODIRATIME;
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
return 0;
diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index 80875aa..8eb787b 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -323,6 +323,7 @@ static int hfsplus_statfs(struct dentry *dentry, struct kstatfs *buf)

static int hfsplus_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
return 0;
if (!(*flags & MS_RDONLY)) {
diff --git a/fs/hpfs/super.c b/fs/hpfs/super.c
index 4534ff6..fe3463a 100644
--- a/fs/hpfs/super.c
+++ b/fs/hpfs/super.c
@@ -421,6 +421,8 @@ static int hpfs_remount_fs(struct super_block *s, int *flags, char *data)
struct hpfs_sb_info *sbi = hpfs_sb(s);
char *new_opts = kstrdup(data, GFP_KERNEL);

+ sync_filesystem(s);
+
*flags |= MS_NOATIME;

hpfs_lock(s);
diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index 4a9e10e..6af66ee 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -117,6 +117,7 @@ static void destroy_inodecache(void)

static int isofs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
if (!(*flags & MS_RDONLY))
return -EROFS;
return 0;
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index 0defb1c..0918f0e 100644
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -243,6 +243,7 @@ static int jffs2_remount_fs(struct super_block *sb, int *flags, char *data)
struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
int err;

+ sync_filesystem(sb);
err = jffs2_parse_options(c, data);
if (err)
return -EINVAL;
diff --git a/fs/jfs/super.c b/fs/jfs/super.c
index e2b7483..97f7fda 100644
--- a/fs/jfs/super.c
+++ b/fs/jfs/super.c
@@ -418,6 +418,7 @@ static int jfs_remount(struct super_block *sb, int *flags, char *data)
int flag = JFS_SBI(sb)->flag;
int ret;

+ sync_filesystem(sb);
if (!parse_options(data, sb, &newLVSize, &flag)) {
return -EINVAL;
}
diff --git a/fs/minix/inode.c b/fs/minix/inode.c
index 0332109..dcdc298 100644
--- a/fs/minix/inode.c
+++ b/fs/minix/inode.c
@@ -123,6 +123,7 @@ static int minix_remount (struct super_block * sb, int * flags, char * data)
struct minix_sb_info * sbi = minix_sb(sb);
struct minix_super_block * ms;

+ sync_filesystem(sb);
ms = sbi->s_ms;
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
return 0;
diff --git a/fs/ncpfs/inode.c b/fs/ncpfs/inode.c
index 2cf2ebe..5f86e80 100644
--- a/fs/ncpfs/inode.c
+++ b/fs/ncpfs/inode.c
@@ -99,6 +99,7 @@ static void destroy_inodecache(void)

static int ncp_remount(struct super_block *sb, int *flags, char* data)
{
+ sync_filesystem(sb);
*flags |= MS_NODIRATIME;
return 0;
}
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 910ed90..2cb5694 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2215,6 +2215,8 @@ nfs_remount(struct super_block *sb, int *flags, char *raw_data)
struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
u32 nfsvers = nfss->nfs_client->rpc_ops->version;

+ sync_filesystem(sb);
+
/*
* Userspace mount programs that send binary options generally send
* them populated with default values. We have no way to know which
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 7ac2a12..8c532b2 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -1129,6 +1129,7 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data)
unsigned long old_mount_opt;
int err;

+ sync_filesystem(sb);
old_sb_flags = sb->s_flags;
old_mount_opt = nilfs->ns_mount_opt;

diff --git a/fs/ntfs/super.c b/fs/ntfs/super.c
index 82650d5..bd5610d 100644
--- a/fs/ntfs/super.c
+++ b/fs/ntfs/super.c
@@ -468,6 +468,8 @@ static int ntfs_remount(struct super_block *sb, int *flags, char *opt)

ntfs_debug("Entering with remount options string: %s", opt);

+ sync_filesystem(sb);
+
#ifndef NTFS_RW
/* For read-only compiled driver, enforce read-only flag. */
*flags |= MS_RDONLY;
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 49d84f8..5f9bf8f 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -631,6 +631,8 @@ static int ocfs2_remount(struct super_block *sb, int *flags, char *data)
struct ocfs2_super *osb = OCFS2_SB(sb);
u32 tmp;

+ sync_filesystem(sb);
+
if (!ocfs2_parse_options(sb, data, &parsed_options, 1) ||
!ocfs2_check_set_options(sb, &parsed_options)) {
ret = -EINVAL;
diff --git a/fs/openpromfs/inode.c b/fs/openpromfs/inode.c
index 8c0ceb8..15e4500 100644
--- a/fs/openpromfs/inode.c
+++ b/fs/openpromfs/inode.c
@@ -368,6 +368,7 @@ static struct inode *openprom_iget(struct super_block *sb, ino_t ino)

static int openprom_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_NOATIME;
return 0;
}
diff --git a/fs/proc/root.c b/fs/proc/root.c
index 87dbcbe..ac823a8 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -92,6 +92,8 @@ static int proc_parse_options(char *options, struct pid_namespace *pid)
int proc_remount(struct super_block *sb, int *flags, char *data)
{
struct pid_namespace *pid = sb->s_fs_info;
+
+ sync_filesystem(sb);
return !proc_parse_options(data, pid);
}

diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 1282384..192297b 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -249,6 +249,7 @@ static void parse_options(char *options)

static int pstore_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
parse_options(data);

return 0;
diff --git a/fs/qnx4/inode.c b/fs/qnx4/inode.c
index 8955881..c4bcb77 100644
--- a/fs/qnx4/inode.c
+++ b/fs/qnx4/inode.c
@@ -44,6 +44,7 @@ static int qnx4_remount(struct super_block *sb, int *flags, char *data)
{
struct qnx4_sb_info *qs;

+ sync_filesystem(sb);
qs = qnx4_sb(sb);
qs->Version = QNX4_VERSION;
*flags |= MS_RDONLY;
diff --git a/fs/qnx6/inode.c b/fs/qnx6/inode.c
index 8d941ed..65cdaab 100644
--- a/fs/qnx6/inode.c
+++ b/fs/qnx6/inode.c
@@ -55,6 +55,7 @@ static int qnx6_show_options(struct seq_file *seq, struct dentry *root)

static int qnx6_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_RDONLY;
return 0;
}
diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c
index 2c80335..abf2b76 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -1319,6 +1319,7 @@ static int reiserfs_remount(struct super_block *s, int *mount_flags, char *arg)
int i;
#endif

+ sync_filesystem(s);
reiserfs_write_lock(s);

#ifdef CONFIG_QUOTA
diff --git a/fs/romfs/super.c b/fs/romfs/super.c
index d841878..ef90e8b 100644
--- a/fs/romfs/super.c
+++ b/fs/romfs/super.c
@@ -432,6 +432,7 @@ static int romfs_statfs(struct dentry *dentry, struct kstatfs *buf)
*/
static int romfs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_RDONLY;
return 0;
}
diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c
index 202df63..031c8d67 100644
--- a/fs/squashfs/super.c
+++ b/fs/squashfs/super.c
@@ -371,6 +371,7 @@ static int squashfs_statfs(struct dentry *dentry, struct kstatfs *buf)

static int squashfs_remount(struct super_block *sb, int *flags, char *data)
{
+ sync_filesystem(sb);
*flags |= MS_RDONLY;
return 0;
}
diff --git a/fs/super.c b/fs/super.c
index 80d5cf2..e9dc3c3 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -719,8 +719,6 @@ int do_remount_sb(struct super_block *sb, int flags, void *data, int force)
}
}

- sync_filesystem(sb);
-
if (sb->s_op->remount_fs) {
retval = sb->s_op->remount_fs(sb, &flags, data);
if (retval) {
diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c
index c327d4e..4742e58 100644
--- a/fs/sysv/inode.c
+++ b/fs/sysv/inode.c
@@ -60,6 +60,7 @@ static int sysv_remount(struct super_block *sb, int *flags, char *data)
{
struct sysv_sb_info *sbi = SYSV_SB(sb);

+ sync_filesystem(sb);
if (sbi->s_forced_ro)
*flags |= MS_RDONLY;
return 0;
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 5ded849..e1598ab 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -1827,6 +1827,7 @@ static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
int err;
struct ubifs_info *c = sb->s_fs_info;

+ sync_filesystem(sb);
dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, *flags);

err = ubifs_parse_options(c, data, 1);
diff --git a/fs/udf/super.c b/fs/udf/super.c
index 3306b9f..64f2b73 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -646,6 +646,7 @@ static int udf_remount_fs(struct super_block *sb, int *flags, char *options)
int error = 0;
struct logicalVolIntegrityDescImpUse *lvidiu = udf_sb_lvidiu(sb);

+ sync_filesystem(sb);
if (lvidiu) {
int write_rev = le16_to_cpu(lvidiu->minUDFWriteRev);
if (write_rev > UDF_MAX_WRITE_VERSION && !(*flags & MS_RDONLY))
diff --git a/fs/ufs/super.c b/fs/ufs/super.c
index 329f2f5..b8c6791 100644
--- a/fs/ufs/super.c
+++ b/fs/ufs/super.c
@@ -1280,6 +1280,7 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
unsigned new_mount_opt, ufstype;
unsigned flags;

+ sync_filesystem(sb);
lock_ufs(sb);
mutex_lock(&UFS_SB(sb)->s_lock);
uspi = UFS_SB(sb)->s_uspi;
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index f317488..aaa3eca 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1197,6 +1197,7 @@ xfs_fs_remount(
char *p;
int error;

+ sync_filesystem(sb);
while ((p = strsep(&options, ",")) != NULL) {
int token;

--
1.9.0