+ /*
+ * On a FS with a 1K blocksize, block 0 is reserved for bootloaders
+ * so we must increment block numbers to any group 0 items.
+ *
+ * However, we cannot touch group_block directly because in the meta_bg
+ * case, the ext2fs_descriptor_block_loc2() function will interpret
+ * group_block != s_first_data_block to mean that we want to access the
+ * backup group descriptors. This is not what we want if the caller
+ * set superblock == 0 (i.e. auto-detect the superblock), which is
+ * what's going on here.
+ */