switch {__,}blockdev_direct_IO() to iov_iter

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index dc69e8f..f5fb09e 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -133,8 +133,7 @@
 	size_t count = iov_iter_count(iter);
 	ssize_t ret;
 
-	ret = blockdev_direct_IO(rw, iocb, inode, iter->iov, offset,
-				 iter->nr_segs, hfs_get_block);
+	ret = blockdev_direct_IO(rw, iocb, inode, iter, offset, hfs_get_block);
 
 	/*
 	 * In case of error extending write may have instantiated a few