1543 	struct st_buffer *STbp = STp->buffer;  in setup_buffering()  local
1552 		i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,  in setup_buffering()
1555 			STbp->do_dio = i;  in setup_buffering()
1556 			STbp->buffer_bytes = 0;   /* can be used as transfer counter */  in setup_buffering()
1559 			STbp->do_dio = 0;  /* fall back to buffering with any error */  in setup_buffering()
1560 		STbp->sg_segs = STbp->do_dio;  in setup_buffering()
1562 		     if (STbp->do_dio) {  in setup_buffering()
1564 			STp->nbr_pages += STbp->do_dio;  in setup_buffering()
1568 		STbp->do_dio = 0;  in setup_buffering()
1571 	if (!STbp->do_dio) {  in setup_buffering()
1579 			if (is_read && STp->sili && !STbp->cleared)  in setup_buffering()
1580 				clear_buffer(STbp);  in setup_buffering()
1583 		if (bufsize > STbp->buffer_size &&  in setup_buffering()
1584 		    !enlarge_buffer(STbp, bufsize)) {  in setup_buffering()
1592 			STbp->buffer_blocks = bufsize / STp->block_size;  in setup_buffering()
1603 	struct st_buffer *STbp;  in release_buffering()  local
1605 	STbp = STp->buffer;  in release_buffering()
1606 	if (STbp->do_dio) {  in release_buffering()
1607 		sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);  in release_buffering()
1608 		STbp->do_dio = 0;  in release_buffering()
1609 		STbp->sg_segs = 0;  in release_buffering()
1629 	struct st_buffer *STbp;  in st_write()  local
1677 	STbp = STp->buffer;  in st_write()
1699 	    !STbp->do_dio &&  in st_write()
1721 		if (STbp->do_dio) {  in st_write()
1728 				do_count = STbp->buffer_blocks * STp->block_size -  in st_write()
1729 					STbp->buffer_bytes;  in st_write()
1734 			i = append_to_buffer(b_point, STbp, do_count);  in st_write()
1743 		async_write = STp->block_size == 0 && !STbp->do_dio &&  in st_write()
1748 		    STbp->buffer_bytes < STbp->buffer_size) {  in st_write()
1759 			if (!STbp->do_dio)  in st_write()
1760 				blks = STbp->buffer_bytes;  in st_write()
1774 			retval = STbp->syscall_result;  in st_write()
1777 		if (async_write && !STbp->syscall_result) {  in st_write()
1778 			STbp->writing = transfer;  in st_write()
1779 			STp->dirty = !(STbp->writing ==  in st_write()
1780 				       STbp->buffer_bytes);  in st_write()
1786 		if (STbp->syscall_result != 0) {  in st_write()
1852 				retval = STbp->syscall_result;  in st_write()
1864 		STbp->buffer_bytes = 0;  in st_write()
1903 	struct st_buffer *STbp;  in read_tape()  local
1913 	STbp = STp->buffer;  in read_tape()
1923 			if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)  in read_tape()
1946 		return STbp->syscall_result;  in read_tape()
1948 	STbp->read_pointer = 0;  in read_tape()
1952 	if (STbp->syscall_result) {  in read_tape()
1991 						STbp->buffer_bytes = 0;  in read_tape()
1994 						STbp->buffer_bytes = bytes - transfer;  in read_tape()
2008 						STbp->buffer_bytes = (blks - transfer) *  in read_tape()
2014 							    STbp->buffer_bytes);  in read_tape()
2026 						STbp->buffer_bytes = 0;  in read_tape()
2028 						STbp->buffer_bytes =  in read_tape()
2032 						    STbp->buffer_bytes);  in read_tape()
2039 						STbp->buffer_bytes = bytes - transfer;  in read_tape()
2041 						STbp->buffer_bytes =  in read_tape()
2046 						    STbp->buffer_bytes);  in read_tape()
2063 			if (STbp->buffer_bytes < 0)  /* Caused by bogus sense data */  in read_tape()
2064 				STbp->buffer_bytes = 0;  in read_tape()
2068 			retval = STbp->syscall_result;  in read_tape()
2074 		STbp->buffer_bytes = bytes;  in read_tape()
2076 			STbp->buffer_bytes -= STp->buffer->cmdstat.residual;  in read_tape()
2083 			STps->drv_block += STbp->buffer_bytes / STp->block_size;  in read_tape()
2101 	struct st_buffer *STbp = STp->buffer;  in st_read()  local
2130 			  STps->eof, STbp->buffer_bytes);  in st_read()
2136 	do_dio = STbp->do_dio;  in st_read()
2138 	if (STbp->buffer_bytes == 0 &&  in st_read()
2168 		if (STbp->buffer_bytes == 0) {  in st_read()
2177 		if (STbp->buffer_bytes > 0) {  in st_read()
2182 					  STps->eof, STbp->buffer_bytes,  in st_read()
2185 			transfer = STbp->buffer_bytes < count - total ?  in st_read()
2186 			    STbp->buffer_bytes : count - total;  in st_read()
2188 				i = from_buffer(STbp, buf, transfer);  in st_read()
2229 		STbp->buffer_bytes = 0;  in st_read()
4859 static int sgl_map_user_pages(struct st_buffer *STbp,  in sgl_map_user_pages()  argument
4868 	struct rq_map_data *mdata = &STbp->map_data;  in sgl_map_user_pages()
4903 	STbp->mapped_pages = pages;  in sgl_map_user_pages()
4917 static int sgl_unmap_user_pages(struct st_buffer *STbp,  in sgl_unmap_user_pages()  argument
4921 	unpin_user_pages_dirty_lock(STbp->mapped_pages, nr_pages, dirtied);  in sgl_unmap_user_pages()
4923 	kfree(STbp->mapped_pages);  in sgl_unmap_user_pages()
4924 	STbp->mapped_pages = NULL;  in sgl_unmap_user_pages()