DESCS_IN_PAGE
#define MAX_DESC_BUFS DIV_ROUND_UP(MAX_NUM_XFERS, DESCS_IN_PAGE)
DIV_ROUND_UP(adap->num_bufs * DATA_BUF_XFERS, DESCS_IN_PAGE);
d = &adap->desc_buf[i - 1].descs[DESCS_IN_PAGE - 1];
for (j = 0; j < DESCS_IN_PAGE; j++) {