Index: linux-2.6/mm/filemap.c
===================================================================
--- linux-2.6.orig/mm/filemap.c	2008-10-03 11:21:31.000000000 +1000
+++ linux-2.6/mm/filemap.c	2008-10-03 12:00:17.000000000 +1000
@@ -1304,11 +1304,8 @@ generic_file_aio_read(struct kiocb *iocb
 			goto out; /* skip atime */
 		size = i_size_read(inode);
 		if (pos < size) {
-			retval = filemap_write_and_wait(mapping);
-			if (!retval) {
-				retval = mapping->a_ops->direct_IO(READ, iocb,
+			retval = mapping->a_ops->direct_IO(READ, iocb,
 							iov, pos, nr_segs);
-			}
 			if (retval > 0)
 				*ppos = pos + retval;
 			if (retval) {
@@ -2110,18 +2107,10 @@ generic_file_direct_write(struct kiocb *
 	if (count != ocount)
 		*nr_segs = iov_shorten((struct iovec *)iov, *nr_segs, count);
 
-	/*
-	 * Unmap all mmappings of the file up-front.
-	 *
-	 * This will cause any pte dirty bits to be propagated into the
-	 * pageframes for the subsequent filemap_write_and_wait().
-	 */
 	write_len = iov_length(iov, *nr_segs);
 	end = (pos + write_len - 1) >> PAGE_CACHE_SHIFT;
-	if (mapping_mapped(mapping))
-		unmap_mapping_range(mapping, pos, write_len, 0);
 
-	written = filemap_write_and_wait(mapping);
+	written = filemap_write_and_wait_range(mapping, pos, pos + write_len - 1);
 	if (written)
 		goto out;
 
@@ -2507,7 +2496,8 @@ generic_file_buffered_write(struct kiocb
 	 * the file data here, to try to honour O_DIRECT expectations.
 	 */
 	if (unlikely(file->f_flags & O_DIRECT) && written)
-		status = filemap_write_and_wait(mapping);
+		status = filemap_write_and_wait_range(mapping,
+					pos, pos + written - 1);
 
 	return written ? written : status;
 }