static int acm_write_buffers_alloc(struct acm *acm)
{
	int i;
	struct acm_wb *wb;

	for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++) {
		wb->buf = usb_alloc_coherent(acm->dev, acm->writesize, GFP_KERNEL,
		    &wb->dmah);
		if (!wb->buf) {
			while (i != 0) {
				--i;
				--wb;
				usb_free_coherent(acm->dev, acm->writesize,
				    wb->buf, wb->dmah);
			}
			return -ENOMEM;
		}
	}
	return 0;
}

Unknown