1549 	struct st_buffer *STbp = STp->buffer;  in setup_buffering()  local
1558 		i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,  in setup_buffering()
1561 			STbp->do_dio = i;  in setup_buffering()
1562 			STbp->buffer_bytes = 0;   /* can be used as transfer counter */  in setup_buffering()
1565 			STbp->do_dio = 0;  /* fall back to buffering with any error */  in setup_buffering()
1566 		STbp->sg_segs = STbp->do_dio;  in setup_buffering()
1568 		     if (STbp->do_dio) {  in setup_buffering()
1570 			STp->nbr_pages += STbp->do_dio;  in setup_buffering()
1574 		STbp->do_dio = 0;  in setup_buffering()
1577 	if (!STbp->do_dio) {  in setup_buffering()
1585 			if (is_read && STp->sili && !STbp->cleared)  in setup_buffering()
1586 				clear_buffer(STbp);  in setup_buffering()
1589 		if (bufsize > STbp->buffer_size &&  in setup_buffering()
1590 		    !enlarge_buffer(STbp, bufsize)) {  in setup_buffering()
1598 			STbp->buffer_blocks = bufsize / STp->block_size;  in setup_buffering()
1609 	struct st_buffer *STbp;  in release_buffering()  local
1611 	STbp = STp->buffer;  in release_buffering()
1612 	if (STbp->do_dio) {  in release_buffering()
1613 		sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);  in release_buffering()
1614 		STbp->do_dio = 0;  in release_buffering()
1615 		STbp->sg_segs = 0;  in release_buffering()
1635 	struct st_buffer *STbp;  in st_write()  local
1683 	STbp = STp->buffer;  in st_write()
1705 	    !STbp->do_dio &&  in st_write()
1727 		if (STbp->do_dio) {  in st_write()
1734 				do_count = STbp->buffer_blocks * STp->block_size -  in st_write()
1735 					STbp->buffer_bytes;  in st_write()
1740 			i = append_to_buffer(b_point, STbp, do_count);  in st_write()
1749 		async_write = STp->block_size == 0 && !STbp->do_dio &&  in st_write()
1754 		    STbp->buffer_bytes < STbp->buffer_size) {  in st_write()
1765 			if (!STbp->do_dio)  in st_write()
1766 				blks = STbp->buffer_bytes;  in st_write()
1780 			retval = STbp->syscall_result;  in st_write()
1783 		if (async_write && !STbp->syscall_result) {  in st_write()
1784 			STbp->writing = transfer;  in st_write()
1785 			STp->dirty = !(STbp->writing ==  in st_write()
1786 				       STbp->buffer_bytes);  in st_write()
1792 		if (STbp->syscall_result != 0) {  in st_write()
1858 				retval = STbp->syscall_result;  in st_write()
1870 		STbp->buffer_bytes = 0;  in st_write()
1909 	struct st_buffer *STbp;  in read_tape()  local
1919 	STbp = STp->buffer;  in read_tape()
1929 			if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)  in read_tape()
1952 		return STbp->syscall_result;  in read_tape()
1954 	STbp->read_pointer = 0;  in read_tape()
1958 	if (STbp->syscall_result) {  in read_tape()
1997 						STbp->buffer_bytes = 0;  in read_tape()
2000 						STbp->buffer_bytes = bytes - transfer;  in read_tape()
2014 						STbp->buffer_bytes = (blks - transfer) *  in read_tape()
2020 							    STbp->buffer_bytes);  in read_tape()
2032 						STbp->buffer_bytes = 0;  in read_tape()
2034 						STbp->buffer_bytes =  in read_tape()
2038 						    STbp->buffer_bytes);  in read_tape()
2045 						STbp->buffer_bytes = bytes - transfer;  in read_tape()
2047 						STbp->buffer_bytes =  in read_tape()
2052 						    STbp->buffer_bytes);  in read_tape()
2069 			if (STbp->buffer_bytes < 0)  /* Caused by bogus sense data */  in read_tape()
2070 				STbp->buffer_bytes = 0;  in read_tape()
2074 			retval = STbp->syscall_result;  in read_tape()
2080 		STbp->buffer_bytes = bytes;  in read_tape()
2082 			STbp->buffer_bytes -= STp->buffer->cmdstat.residual;  in read_tape()
2089 			STps->drv_block += STbp->buffer_bytes / STp->block_size;  in read_tape()
2107 	struct st_buffer *STbp = STp->buffer;  in st_read()  local
2136 			  STps->eof, STbp->buffer_bytes);  in st_read()
2142 	do_dio = STbp->do_dio;  in st_read()
2144 	if (STbp->buffer_bytes == 0 &&  in st_read()
2174 		if (STbp->buffer_bytes == 0) {  in st_read()
2183 		if (STbp->buffer_bytes > 0) {  in st_read()
2188 					  STps->eof, STbp->buffer_bytes,  in st_read()
2191 			transfer = STbp->buffer_bytes < count - total ?  in st_read()
2192 			    STbp->buffer_bytes : count - total;  in st_read()
2194 				i = from_buffer(STbp, buf, transfer);  in st_read()
2235 		STbp->buffer_bytes = 0;  in st_read()
4863 static int sgl_map_user_pages(struct st_buffer *STbp,  in sgl_map_user_pages()  argument
4872 	struct rq_map_data *mdata = &STbp->map_data;  in sgl_map_user_pages()
4907 	STbp->mapped_pages = pages;  in sgl_map_user_pages()
4921 static int sgl_unmap_user_pages(struct st_buffer *STbp,  in sgl_unmap_user_pages()  argument
4925 	unpin_user_pages_dirty_lock(STbp->mapped_pages, nr_pages, dirtied);  in sgl_unmap_user_pages()
4927 	kfree(STbp->mapped_pages);  in sgl_unmap_user_pages()
4928 	STbp->mapped_pages = NULL;  in sgl_unmap_user_pages()