Remove rw from {,__,do_}blockdev_direct_IO()

Most filesystems call through to these at some point, so we'll start
here.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/affs/file.c

@@ -405,7 +405,7 @@ affs_direct_IO(int rw, struct kiocb *iocb, struct iov_iter *iter,
 			return 0;
 	}
 
-	ret = blockdev_direct_IO(rw, iocb, inode, iter, offset, affs_get_block);
+	ret = blockdev_direct_IO(iocb, inode, iter, offset, affs_get_block);
 	if (ret < 0 && (rw & WRITE))
 		affs_write_failed(mapping, offset + count);
 	return ret;