CISS_MAX_SG_ELEMENTS
cpi->maxio = (min(CISS_MAX_SG_ELEMENTS, sg_length) - 1) * PAGE_SIZE;
(CISS_MAX_SG_ELEMENTS - 1) * PAGE_SIZE, /* maxsize */
CISS_MAX_SG_ELEMENTS, /* nsegments */
#define CISS_COMMAND_SG_LENGTH (sizeof(struct ciss_sg_entry) * CISS_MAX_SG_ELEMENTS)