@@ -8889,6 +8889,48 @@ out:
return err;
}
+/*
+ * Check referencer for shared block backref
+ * If level == -1, this function will resolve the level.
+ */
+static int check_shared_block_backref(struct btrfs_fs_info *fs_info,
+ u64 parent, u64 bytenr, int level)
+{
+ struct extent_buffer *eb;
+ u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
+ u32 nr;
+ int found_parent = 0;
+ int i;
+
+ eb = read_tree_block_fs_info(fs_info, parent, nodesize, 0);
+ if (!extent_buffer_uptodate(eb))
+ goto out;
+
+ if (level == -1)
+ level = query_tree_block_level(fs_info, bytenr);
+ if (level < 0)
+ goto out;
+
+ if (level + 1 != btrfs_header_level(eb))
+ goto out;
+
+ nr = btrfs_header_nritems(eb);
+ for (i = 0; i < nr; i++) {
+ if (bytenr == btrfs_node_blockptr(eb, i)) {
+ found_parent = 1;
+ break;
+ }
+ }
+out:
+ free_extent_buffer(eb);
+ if (!found_parent) {
+ error("Shared extent[%llu %u] lost its parent(parent: %llu, level: %u)",
+ bytenr, nodesize, parent, level);
+ return REFERENCER_MISSING;
+ }
+ return 0;
+}
+
static int btrfs_fsck_reinit_root(struct btrfs_trans_handle *trans,
struct btrfs_root *root, int overwrite)
{