1575 	struct st_buffer *STbp = STp->buffer;  in setup_buffering()  local
1584 		i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,  in setup_buffering()
1587 			STbp->do_dio = i;  in setup_buffering()
1588 			STbp->buffer_bytes = 0;   /* can be used as transfer counter */  in setup_buffering()
1591 			STbp->do_dio = 0;  /* fall back to buffering with any error */  in setup_buffering()
1592 		STbp->sg_segs = STbp->do_dio;  in setup_buffering()
1594 		     if (STbp->do_dio) {  in setup_buffering()
1596 			STp->nbr_pages += STbp->do_dio;  in setup_buffering()
1600 		STbp->do_dio = 0;  in setup_buffering()
1603 	if (!STbp->do_dio) {  in setup_buffering()
1611 			if (is_read && STp->sili && !STbp->cleared)  in setup_buffering()
1612 				clear_buffer(STbp);  in setup_buffering()
1615 		if (bufsize > STbp->buffer_size &&  in setup_buffering()
1616 		    !enlarge_buffer(STbp, bufsize)) {  in setup_buffering()
1624 			STbp->buffer_blocks = bufsize / STp->block_size;  in setup_buffering()
1635 	struct st_buffer *STbp;  in release_buffering()  local
1637 	STbp = STp->buffer;  in release_buffering()
1638 	if (STbp->do_dio) {  in release_buffering()
1639 		sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);  in release_buffering()
1640 		STbp->do_dio = 0;  in release_buffering()
1641 		STbp->sg_segs = 0;  in release_buffering()
1661 	struct st_buffer *STbp;  in st_write()  local
1709 	STbp = STp->buffer;  in st_write()
1731 	    !STbp->do_dio &&  in st_write()
1753 		if (STbp->do_dio) {  in st_write()
1760 				do_count = STbp->buffer_blocks * STp->block_size -  in st_write()
1761 					STbp->buffer_bytes;  in st_write()
1766 			i = append_to_buffer(b_point, STbp, do_count);  in st_write()
1775 		async_write = STp->block_size == 0 && !STbp->do_dio &&  in st_write()
1780 		    STbp->buffer_bytes < STbp->buffer_size) {  in st_write()
1791 			if (!STbp->do_dio)  in st_write()
1792 				blks = STbp->buffer_bytes;  in st_write()
1806 			retval = STbp->syscall_result;  in st_write()
1809 		if (async_write && !STbp->syscall_result) {  in st_write()
1810 			STbp->writing = transfer;  in st_write()
1811 			STp->dirty = !(STbp->writing ==  in st_write()
1812 				       STbp->buffer_bytes);  in st_write()
1818 		if (STbp->syscall_result != 0) {  in st_write()
1884 				retval = STbp->syscall_result;  in st_write()
1896 		STbp->buffer_bytes = 0;  in st_write()
1935 	struct st_buffer *STbp;  in read_tape()  local
1945 	STbp = STp->buffer;  in read_tape()
1955 			if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)  in read_tape()
1978 		return STbp->syscall_result;  in read_tape()
1980 	STbp->read_pointer = 0;  in read_tape()
1984 	if (STbp->syscall_result) {  in read_tape()
2023 						STbp->buffer_bytes = 0;  in read_tape()
2026 						STbp->buffer_bytes = bytes - transfer;  in read_tape()
2040 						STbp->buffer_bytes = (blks - transfer) *  in read_tape()
2046 							    STbp->buffer_bytes);  in read_tape()
2058 						STbp->buffer_bytes = 0;  in read_tape()
2060 						STbp->buffer_bytes =  in read_tape()
2064 						    STbp->buffer_bytes);  in read_tape()
2071 						STbp->buffer_bytes = bytes - transfer;  in read_tape()
2073 						STbp->buffer_bytes =  in read_tape()
2078 						    STbp->buffer_bytes);  in read_tape()
2095 			if (STbp->buffer_bytes < 0)  /* Caused by bogus sense data */  in read_tape()
2096 				STbp->buffer_bytes = 0;  in read_tape()
2100 			retval = STbp->syscall_result;  in read_tape()
2106 		STbp->buffer_bytes = bytes;  in read_tape()
2108 			STbp->buffer_bytes -= STp->buffer->cmdstat.residual;  in read_tape()
2115 			STps->drv_block += STbp->buffer_bytes / STp->block_size;  in read_tape()
2133 	struct st_buffer *STbp = STp->buffer;  in st_read()  local
2162 			  STps->eof, STbp->buffer_bytes);  in st_read()
2168 	do_dio = STbp->do_dio;  in st_read()
2170 	if (STbp->buffer_bytes == 0 &&  in st_read()
2200 		if (STbp->buffer_bytes == 0) {  in st_read()
2209 		if (STbp->buffer_bytes > 0) {  in st_read()
2214 					  STps->eof, STbp->buffer_bytes,  in st_read()
2217 			transfer = STbp->buffer_bytes < count - total ?  in st_read()
2218 			    STbp->buffer_bytes : count - total;  in st_read()
2220 				i = from_buffer(STbp, buf, transfer);  in st_read()
2261 		STbp->buffer_bytes = 0;  in st_read()
4986 static int sgl_map_user_pages(struct st_buffer *STbp,  in sgl_map_user_pages()  argument
4995 	struct rq_map_data *mdata = &STbp->map_data;  in sgl_map_user_pages()
5030 	STbp->mapped_pages = pages;  in sgl_map_user_pages()
5044 static int sgl_unmap_user_pages(struct st_buffer *STbp,  in sgl_unmap_user_pages()  argument
5048 	unpin_user_pages_dirty_lock(STbp->mapped_pages, nr_pages, dirtied);  in sgl_unmap_user_pages()
5050 	kfree(STbp->mapped_pages);  in sgl_unmap_user_pages()
5051 	STbp->mapped_pages = NULL;  in sgl_unmap_user_pages()