From 02b9984d640873b7b3809e63f81a0d7e13496886 Mon Sep 17 00:00:00 2001
From: Theodore Ts'o <tytso@mit.edu>
Date: Thu, 13 Mar 2014 10:14:33 -0400
Subject: fs: push sync_filesystem() down to the file system's remount_fs()

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(-)

(limited to 'fs')

diff --git a/fs/adfs/super.c b/fs/adfs/super.c
index 7b3003cb6f1..952aeb04834 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 d098731b82f..307453086c3 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 845d2d690ce..56d70c8a89b 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 97cc2419855..00cd0c57b0b 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 849f6132b32..4942c94bf7e 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 506de34a4ef..3f48000ef1a 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 06610cf94d5..a2759112563 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 9c0444cccbe..02928a9d00a 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 a726b9f29cb..c71038079b4 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 50215bbd646..103bbd820b8 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 20d6697bd63..d260115c035 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 37fd31ed16e..95c6c5a6d0c 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 7a829f75023..a5f1170048b 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4765,6 +4765,8 @@ 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 1a85f83abd5..856bdf994c0 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 854b578f669..343e477c6dc 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 e37eb274e49..7ca8c75d50d 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 d468643a68b..ecdb255d086 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 60f60f6181f..4c6dd50831b 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 2d2039e754c..eee7206c38d 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 80875aa640e..8eb787b52c0 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 4534ff688b7..fe3463a4323 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 4a9e10ea13f..6af66ee5639 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 0defb1cc2a3..0918f0e2e26 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 e2b7483444f..97f7fda5189 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 0332109162a..dcdc2989370 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 2cf2ebecb55..5f86e808017 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 910ed906eb8..2cb56943e23 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 7ac2a122ca1..8c532b2ca3a 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 82650d52d91..bd5610d4824 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 49d84f80f36..5f9bf8f9dfa 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 8c0ceb8dd1f..15e4500cda3 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 87dbcbef7fe..ac823a85cf6 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 12823845d32..192297b0090 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 89558810381..c4bcb778886 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 8d941edfefa..65cdaab3ed4 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 2c803353f8a..abf2b76c0d1 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 d8418782862..ef90e8bca95 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 202df6312d4..031c8d67fd5 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 80d5cf2ca76..e9dc3c3fe15 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 c327d4ee123..4742e58f3fc 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 5ded8490c0c..e1598abd747 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 3306b9f69be..64f2b7334d0 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 329f2f53b7e..b8c6791f046 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 f317488263d..aaa3eca3f23 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;
 
-- 
cgit v1.2.3-18-g5258