direct-io: eliminate the offset argument to ->direct_IO

Including blkdev_direct_IO and dax_do_io.  It has to be ki_pos to actually
work, so eliminate the superflous argument.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 5346313..cfebcd2 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -305,7 +305,7 @@
 }
 
 static ssize_t
-nilfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter, loff_t offset)
+nilfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 {
 	struct inode *inode = file_inode(iocb->ki_filp);
 
@@ -313,7 +313,7 @@
 		return 0;
 
 	/* Needs synchronization with the cleaner */
-	return blockdev_direct_IO(iocb, inode, iter, offset, nilfs_get_block);
+	return blockdev_direct_IO(iocb, inode, iter, nilfs_get_block);
 }
 
 const struct address_space_operations nilfs_aops = {