Btrfs: Add back metadata checksumming

Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index e4e68ea..6b2f2b4 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1178,6 +1178,10 @@
 	btrfs_set_buffer_uptodate(buf);
 	set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
 			 buf->start + buf->len - 1, GFP_NOFS);
+	set_extent_bits(&BTRFS_I(root->fs_info->btree_inode)->extent_tree,
+			buf->start, buf->start + buf->len - 1,
+			EXTENT_CSUM, GFP_NOFS);
+	buf->flags |= EXTENT_CSUM;
 	btrfs_set_buffer_defrag(buf);
 	trans->blocks_used++;
 	return buf;