1493 	struct st_buffer *STbp = STp->buffer;  in setup_buffering()  local
1502 		i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,  in setup_buffering()
1505 			STbp->do_dio = i;  in setup_buffering()
1506 			STbp->buffer_bytes = 0;   /* can be used as transfer counter */  in setup_buffering()
1509 			STbp->do_dio = 0;  /* fall back to buffering with any error */  in setup_buffering()
1510 		STbp->sg_segs = STbp->do_dio;  in setup_buffering()
1512 		     if (STbp->do_dio) {  in setup_buffering()
1514 			STp->nbr_pages += STbp->do_dio;  in setup_buffering()
1518 		STbp->do_dio = 0;  in setup_buffering()
1521 	if (!STbp->do_dio) {  in setup_buffering()
1529 			if (is_read && STp->sili && !STbp->cleared)  in setup_buffering()
1530 				clear_buffer(STbp);  in setup_buffering()
1533 		if (bufsize > STbp->buffer_size &&  in setup_buffering()
1534 		    !enlarge_buffer(STbp, bufsize, STp->restr_dma)) {  in setup_buffering()
1542 			STbp->buffer_blocks = bufsize / STp->block_size;  in setup_buffering()
1553 	struct st_buffer *STbp;  in release_buffering()  local
1555 	STbp = STp->buffer;  in release_buffering()
1556 	if (STbp->do_dio) {  in release_buffering()
1557 		sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);  in release_buffering()
1558 		STbp->do_dio = 0;  in release_buffering()
1559 		STbp->sg_segs = 0;  in release_buffering()
1579 	struct st_buffer *STbp;  in st_write()  local
1627 	STbp = STp->buffer;  in st_write()
1649 	    !STbp->do_dio &&  in st_write()
1671 		if (STbp->do_dio) {  in st_write()
1678 				do_count = STbp->buffer_blocks * STp->block_size -  in st_write()
1679 					STbp->buffer_bytes;  in st_write()
1684 			i = append_to_buffer(b_point, STbp, do_count);  in st_write()
1693 		async_write = STp->block_size == 0 && !STbp->do_dio &&  in st_write()
1698 		    STbp->buffer_bytes < STbp->buffer_size) {  in st_write()
1709 			if (!STbp->do_dio)  in st_write()
1710 				blks = STbp->buffer_bytes;  in st_write()
1724 			retval = STbp->syscall_result;  in st_write()
1727 		if (async_write && !STbp->syscall_result) {  in st_write()
1728 			STbp->writing = transfer;  in st_write()
1729 			STp->dirty = !(STbp->writing ==  in st_write()
1730 				       STbp->buffer_bytes);  in st_write()
1736 		if (STbp->syscall_result != 0) {  in st_write()
1802 				retval = STbp->syscall_result;  in st_write()
1814 		STbp->buffer_bytes = 0;  in st_write()
1853 	struct st_buffer *STbp;  in read_tape()  local
1863 	STbp = STp->buffer;  in read_tape()
1873 			if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)  in read_tape()
1896 		return STbp->syscall_result;  in read_tape()
1898 	STbp->read_pointer = 0;  in read_tape()
1902 	if (STbp->syscall_result) {  in read_tape()
1938 						STbp->buffer_bytes = 0;  in read_tape()
1941 						STbp->buffer_bytes = bytes - transfer;  in read_tape()
1955 						STbp->buffer_bytes = (blks - transfer) *  in read_tape()
1961 							    STbp->buffer_bytes);  in read_tape()
1973 						STbp->buffer_bytes = 0;  in read_tape()
1975 						STbp->buffer_bytes =  in read_tape()
1979 						    STbp->buffer_bytes);  in read_tape()
1986 						STbp->buffer_bytes = bytes - transfer;  in read_tape()
1988 						STbp->buffer_bytes =  in read_tape()
1993 						    STbp->buffer_bytes);  in read_tape()
2010 			if (STbp->buffer_bytes < 0)  /* Caused by bogus sense data */  in read_tape()
2011 				STbp->buffer_bytes = 0;  in read_tape()
2015 			retval = STbp->syscall_result;  in read_tape()
2021 		STbp->buffer_bytes = bytes;  in read_tape()
2023 			STbp->buffer_bytes -= STp->buffer->cmdstat.residual;  in read_tape()
2030 			STps->drv_block += STbp->buffer_bytes / STp->block_size;  in read_tape()
2048 	struct st_buffer *STbp = STp->buffer;  in st_read()  local
2077 			  STps->eof, STbp->buffer_bytes);  in st_read()
2083 	do_dio = STbp->do_dio;  in st_read()
2085 	if (STbp->buffer_bytes == 0 &&  in st_read()
2115 		if (STbp->buffer_bytes == 0) {  in st_read()
2124 		if (STbp->buffer_bytes > 0) {  in st_read()
2129 					  STps->eof, STbp->buffer_bytes,  in st_read()
2132 			transfer = STbp->buffer_bytes < count - total ?  in st_read()
2133 			    STbp->buffer_bytes : count - total;  in st_read()
2135 				i = from_buffer(STbp, buf, transfer);  in st_read()
2176 		STbp->buffer_bytes = 0;  in st_read()
4527 static int sgl_map_user_pages(struct st_buffer *STbp,  in sgl_map_user_pages()  argument
4536 	struct rq_map_data *mdata = &STbp->map_data;  in sgl_map_user_pages()
4576 	STbp->mapped_pages = pages;  in sgl_map_user_pages()
4591 static int sgl_unmap_user_pages(struct st_buffer *STbp,  in sgl_unmap_user_pages()  argument
4597 		struct page *page = STbp->mapped_pages[i];  in sgl_unmap_user_pages()
4606 	kfree(STbp->mapped_pages);  in sgl_unmap_user_pages()
4607 	STbp->mapped_pages = NULL;  in sgl_unmap_user_pages()