f2fs: fix parameters of __exchange_data_block

__exchange_data_block should take block indexes as parameters
instead of offsets in bytes.

Signed-off-by: Fan li <fanofcode.li@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index b8a521f..40fe72e 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -2143,8 +2143,9 @@
 
 	f2fs_balance_fs(sbi, true);
 	f2fs_lock_op(sbi);
-	ret = __exchange_data_block(src, dst, pos_in,
-				pos_out, len >> F2FS_BLKSIZE_BITS, false);
+	ret = __exchange_data_block(src, dst, pos_in >> F2FS_BLKSIZE_BITS,
+				pos_out >> F2FS_BLKSIZE_BITS,
+				len >> F2FS_BLKSIZE_BITS, false);
 
 	if (!ret) {
 		if (dst_max_i_size)