695 	if (STps->drv_block >= 0) {  in write_behind_check()
697 			STps->drv_block++;  in write_behind_check()
699 			STps->drv_block += STbuffer->writing / STp->block_size;  in write_behind_check()
715 			STps->drv_block = -1;  in write_behind_check()
810 				if (STps->drv_block >= 0)  in st_flush_write_buffer()
811 					STps->drv_block += blks;  in st_flush_write_buffer()
815 				STps->drv_block = (-1);  in st_flush_write_buffer()
819 			if (STps->drv_block >= 0)  in st_flush_write_buffer()
820 				STps->drv_block += blks;  in st_flush_write_buffer()
869 				STps->drv_block = 0;  in flush_buffer()
877 		STps->drv_block = 0;  in flush_buffer()
948 		STps->drv_block = -1;  in reset_state()
1084 			STps->drv_block = 0;  in check_tape()
1101 			STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);  in check_tape()
1407 			STps->drv_block = 0;  in st_flush()
1432 					STps->drv_block = 0;  in st_flush()
1442 			STps->drv_block = 0;  in st_flush()
1667 		   STps->drv_file == 0 && STps->drv_block == 0) {  in st_write()
1832 						if (STps->drv_block >= 0) {  in st_write()
1833 							STps->drv_block += (transfer - undone) /  in st_write()
1849 						STps->drv_block = (-1); /* Too cautious? */  in st_write()
1857 				STps->drv_block = (-1);		/* Too cautious? */  in st_write()
1863 		if (STps->drv_block >= 0) {  in st_write()
1865 				STps->drv_block += (do_count > 0);  in st_write()
1867 				STps->drv_block += blks;  in st_write()
1995 						if (STps->drv_block >= 0)  in read_tape()
1996 							STps->drv_block += 1;  in read_tape()
2008 							if (STps->drv_block >= 0)  in read_tape()
2009 								STps->drv_block += blks - transfer + 1;  in read_tape()
2021 						if (STps->drv_block >= 0)  in read_tape()
2022 							STps->drv_block += 1;  in read_tape()
2058 				STps->drv_block = (-1);  in read_tape()
2085 	if (STps->drv_block >= 0) {  in read_tape()
2087 			STps->drv_block++;  in read_tape()
2089 			STps->drv_block += STbp->buffer_bytes / STp->block_size;  in read_tape()
2214 			STps->drv_block = 0;  in st_read()
2219 			STps->drv_block = 0;  in st_read()
2668 		STps->drv_file = STps->drv_block = (-1);  in do_load_unload()
2720 	blkno = STps->drv_block;  in st_int_ioctl()
2970 		STps->drv_block = blkno;  in st_int_ioctl()
3010 			STps->drv_block = 0;  in st_int_ioctl()
3037 			STps->drv_block = -1;  in st_int_ioctl()
3044 			STps->drv_block = 0;  in st_int_ioctl()
3050 				STps->drv_block = 0;  in st_int_ioctl()
3054 					STps->drv_block = blkno - undone;  in st_int_ioctl()
3056 					STps->drv_block = (-1);  in st_int_ioctl()
3062 				STps->drv_block = (-1);  in st_int_ioctl()
3066 				if (STps->drv_block >= 0)  in st_int_ioctl()
3067 					STps->drv_block = blkno + undone;  in st_int_ioctl()
3072 			STps->drv_block = (-1);  in st_int_ioctl()
3150 				STp->ps[0].drv_block = STp->ps[0].drv_file = 0;  in get_location()
3233 	STps->drv_block = STps->drv_file = (-1);  in set_location()
3253 			STps->drv_block = STps->drv_file = 0;  in set_location()
3690 			STps->drv_block = STps->drv_file = 0;  in st_ioctl()
3757 		mt_status.mt_blkno = STps->drv_block;  in st_ioctl()
4336 		STps->drv_block = (-1);  in st_probe()