* any child cgroups exist. This is theoretically supportable
* but involves complex error handling, so it's being left until
* later */
- if (!list_empty(&cgrp->children))
+ if (root->number_of_cgroups > 1)
return -EBUSY;
/* Process each subsystem */
if (ret == -EBUSY) {
mutex_unlock(&cgroup_mutex);
mutex_unlock(&inode->i_mutex);
- goto drop_new_super;
+ goto free_cg_links;
}
/* EBUSY should be the only error here */
return simple_set_mnt(mnt, sb);
+ free_cg_links:
+ free_cg_links(&tmp_cg_links);
drop_new_super:
up_write(&sb->s_umount);
deactivate_super(sb);
- free_cg_links(&tmp_cg_links);
return ret;
}
struct cgroup *cgrp;
struct cgroup_iter it;
struct task_struct *tsk;
+
/*
- * Validate dentry by checking the superblock operations
+ * Validate dentry by checking the superblock operations,
+ * and make sure it's a directory.
*/
- if (dentry->d_sb->s_op != &cgroup_ops)
+ if (dentry->d_sb->s_op != &cgroup_ops ||
+ !S_ISDIR(dentry->d_inode->i_mode))
goto err;
ret = 0;
mutex_unlock(&cgroup_mutex);
return -EBUSY;
}
-
- parent = cgrp->parent;
- root = cgrp->root;
- sb = root->sb;
+ mutex_unlock(&cgroup_mutex);
/*
* Call pre_destroy handlers of subsys. Notify subsystems
*/
cgroup_call_pre_destroy(cgrp);
- if (cgroup_has_css_refs(cgrp)) {
+ mutex_lock(&cgroup_mutex);
+ parent = cgrp->parent;
+ root = cgrp->root;
+ sb = root->sb;
+
+ if (atomic_read(&cgrp->count)
+ || !list_empty(&cgrp->children)
+ || cgroup_has_css_refs(cgrp)) {
mutex_unlock(&cgroup_mutex);
return -EBUSY;
}
again:
root = subsys->root;
if (root == &rootnode) {
- printk(KERN_INFO
- "Not cloning cgroup for unused subsystem %s\n",
- subsys->name);
mutex_unlock(&cgroup_mutex);
return 0;
}