*/
int generic_show_options(struct seq_file *m, struct vfsmount *mnt)
{
- const char *options = mnt->mnt_sb->s_options;
+ const char *options;
+
+ rcu_read_lock();
+ options = rcu_dereference(mnt->mnt_sb->s_options);
if (options != NULL && options[0]) {
seq_putc(m, ',');
mangle(m, options);
}
+ rcu_read_unlock();
return 0;
}
*/
void save_mount_options(struct super_block *sb, char *options)
{
- kfree(sb->s_options);
- sb->s_options = kstrdup(options, GFP_KERNEL);
+ BUG_ON(sb->s_options);
+ rcu_assign_pointer(sb->s_options, kstrdup(options, GFP_KERNEL));
}
EXPORT_SYMBOL(save_mount_options);
+void replace_mount_options(struct super_block *sb, char *options)
+{
+ char *old = sb->s_options;
+ rcu_assign_pointer(sb->s_options, options);
+ if (old) {
+ synchronize_rcu();
+ kfree(old);
+ }
+}
+EXPORT_SYMBOL(replace_mount_options);
+
#ifdef CONFIG_PROC_FS
/* iterator */
static void *m_start(struct seq_file *m, loff_t *pos)
*/
if (flags & MNT_FORCE && sb->s_op->umount_begin) {
- lock_kernel();
sb->s_op->umount_begin(sb);
- unlock_kernel();
}
/*
return NULL;
}
-struct vfsmount *collect_mounts(struct vfsmount *mnt, struct dentry *dentry)
+struct vfsmount *collect_mounts(struct path *path)
{
struct vfsmount *tree;
down_write(&namespace_sem);
- tree = copy_tree(mnt, dentry, CL_COPY_ALL | CL_PRIVATE);
+ tree = copy_tree(path->mnt, path->dentry, CL_COPY_ALL | CL_PRIVATE);
up_write(&namespace_sem);
return tree;
}
down_write(&namespace_sem);
while (d_mountpoint(path->dentry) &&
- follow_down(&path->mnt, &path->dentry))
+ follow_down(path))
;
err = -EINVAL;
if (!check_mnt(path->mnt) || !check_mnt(old_path.mnt))
down_write(&namespace_sem);
/* Something was mounted here while we slept */
while (d_mountpoint(path->dentry) &&
- follow_down(&path->mnt, &path->dentry))
+ follow_down(path))
;
err = -EINVAL;
- if (!check_mnt(path->mnt))
+ if (!(mnt_flags & MNT_SHRINKABLE) && !check_mnt(path->mnt))
goto unlock;
/* Refuse the same filesystem on the same mount point */