rem: return EPERM;
add: return FS_EPERM;
context: sys_open_query(bool kernel, int fd, const char *path, const char *query, ulong flags, port_id port, ulong token, void **cookie){	int		err;	nspace	*ns;	fsystem	*fs;	vnode	*root;	TRACE("sys_open_query() -- start\n");	err = get_file_fd(TRUE, fd, path, TRUE, &root);	if (err)		return err;	ns = root->ns;	fs = ns->fs;	if (ns->root != root)		return EINVAL;	if (fs->ops.open_query == NULL) {		dec_vnode(root, FALSE);		return EPERM;	}	err = (*fs->ops.open_query)(ns->data, query, flags, port, token, cookie);	TRACE("sys_open_query() -- end: %d\n",err);	dec_vnode(root, FALSE);	return err;}