Push lock_super() into the ->remount_fs() of filesystems that care about it
Note that since we can't run into contention between remount_fs and write_super
(due to exclusion on s_umount), we have to care only about filesystems that
touch lock_super() on their own. Out of those ext3, ext4, hpfs, sysv and ufs
do need it; fat doesn't since its ->remount_fs() only accesses assign-once
data (basically, it's "we have no atime on directories and only have atime on
files for vfat; force nodiratime and possibly noatime into *flags").
[folded a build fix from hch]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ext3/super.c b/fs/ext3/super.c
index 546b8d7..e213a26 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -2491,6 +2491,7 @@
#endif
/* Store the original options */
+ lock_super(sb);
old_sb_flags = sb->s_flags;
old_opts.s_mount_opt = sbi->s_mount_opt;
old_opts.s_resuid = sbi->s_resuid;
@@ -2598,6 +2599,7 @@
old_opts.s_qf_names[i] != sbi->s_qf_names[i])
kfree(old_opts.s_qf_names[i]);
#endif
+ unlock_super(sb);
return 0;
restore_opts:
sb->s_flags = old_sb_flags;
@@ -2614,6 +2616,7 @@
sbi->s_qf_names[i] = old_opts.s_qf_names[i];
}
#endif
+ unlock_super(sb);
return err;
}
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 1d4180b..a9c6834 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3421,6 +3421,7 @@
#endif
/* Store the original options */
+ lock_super(sb);
old_sb_flags = sb->s_flags;
old_opts.s_mount_opt = sbi->s_mount_opt;
old_opts.s_resuid = sbi->s_resuid;
@@ -3554,6 +3555,7 @@
old_opts.s_qf_names[i] != sbi->s_qf_names[i])
kfree(old_opts.s_qf_names[i]);
#endif
+ unlock_super(sb);
return 0;
restore_opts:
@@ -3573,6 +3575,7 @@
sbi->s_qf_names[i] = old_opts.s_qf_names[i];
}
#endif
+ unlock_super(sb);
return err;
}
diff --git a/fs/hpfs/super.c b/fs/hpfs/super.c
index 437a32e..f68193c 100644
--- a/fs/hpfs/super.c
+++ b/fs/hpfs/super.c
@@ -398,6 +398,7 @@
*flags |= MS_NOATIME;
+ lock_super(s);
uid = sbi->sb_uid; gid = sbi->sb_gid;
umask = 0777 & ~sbi->sb_mode;
lowercase = sbi->sb_lowercase; conv = sbi->sb_conv;
@@ -430,9 +431,11 @@
replace_mount_options(s, new_opts);
+ unlock_super(s);
return 0;
out_err:
+ unlock_super(s);
kfree(new_opts);
return -EINVAL;
}
diff --git a/fs/super.c b/fs/super.c
index bdd7158..2a49fed 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -556,9 +556,7 @@
remount_rw = !(flags & MS_RDONLY) && (sb->s_flags & MS_RDONLY);
if (sb->s_op->remount_fs) {
- lock_super(sb);
retval = sb->s_op->remount_fs(sb, &flags, data);
- unlock_super(sb);
if (retval)
return retval;
}
diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c
index a818986..e0a39f1 100644
--- a/fs/sysv/inode.c
+++ b/fs/sysv/inode.c
@@ -61,10 +61,12 @@
static int sysv_remount(struct super_block *sb, int *flags, char *data)
{
struct sysv_sb_info *sbi = SYSV_SB(sb);
+ lock_super(sb);
if (sbi->s_forced_ro)
*flags |= MS_RDONLY;
if (!(*flags & MS_RDONLY))
sb->s_dirt = 1;
+ unlock_super(sb);
return 0;
}
diff --git a/fs/ufs/super.c b/fs/ufs/super.c
index 2b4d2b6..a5ecabf 100644
--- a/fs/ufs/super.c
+++ b/fs/ufs/super.c
@@ -1181,6 +1181,7 @@
unsigned new_mount_opt, ufstype;
unsigned flags;
+ lock_super(sb);
uspi = UFS_SB(sb)->s_uspi;
flags = UFS_SB(sb)->s_flags;
usb1 = ubh_get_usb_first(uspi);
@@ -1193,17 +1194,21 @@
ufstype = UFS_SB(sb)->s_mount_opt & UFS_MOUNT_UFSTYPE;
new_mount_opt = 0;
ufs_set_opt (new_mount_opt, ONERROR_LOCK);
- if (!ufs_parse_options (data, &new_mount_opt))
+ if (!ufs_parse_options (data, &new_mount_opt)) {
+ unlock_super(sb);
return -EINVAL;
+ }
if (!(new_mount_opt & UFS_MOUNT_UFSTYPE)) {
new_mount_opt |= ufstype;
} else if ((new_mount_opt & UFS_MOUNT_UFSTYPE) != ufstype) {
printk("ufstype can't be changed during remount\n");
+ unlock_super(sb);
return -EINVAL;
}
if ((*mount_flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
UFS_SB(sb)->s_mount_opt = new_mount_opt;
+ unlock_super(sb);
return 0;
}
@@ -1228,6 +1233,7 @@
#ifndef CONFIG_UFS_FS_WRITE
printk("ufs was compiled with read-only support, "
"can't be mounted as read-write\n");
+ unlock_super(sb);
return -EINVAL;
#else
if (ufstype != UFS_MOUNT_UFSTYPE_SUN &&
@@ -1236,16 +1242,19 @@
ufstype != UFS_MOUNT_UFSTYPE_SUNx86 &&
ufstype != UFS_MOUNT_UFSTYPE_UFS2) {
printk("this ufstype is read-only supported\n");
+ unlock_super(sb);
return -EINVAL;
}
if (!ufs_read_cylinder_structures(sb)) {
printk("failed during remounting\n");
+ unlock_super(sb);
return -EPERM;
}
sb->s_flags &= ~MS_RDONLY;
#endif
}
UFS_SB(sb)->s_mount_opt = new_mount_opt;
+ unlock_super(sb);
return 0;
}