extern void ext2fs_mark_bb_dirty(ext2_filsys fs);
extern int ext2fs_test_ib_dirty(ext2_filsys fs);
extern int ext2fs_test_bb_dirty(ext2_filsys fs);
-extern int ext2fs_group_of_blk(ext2_filsys fs, blk_t blk);
-extern int ext2fs_group_of_ino(ext2_filsys fs, ext2_ino_t ino);
+extern dgrp_t ext2fs_group_of_blk(ext2_filsys fs, blk_t blk);
+extern dgrp_t ext2fs_group_of_ino(ext2_filsys fs, ext2_ino_t ino);
extern blk_t ext2fs_group_first_block(ext2_filsys fs, dgrp_t group);
extern blk_t ext2fs_group_last_block(ext2_filsys fs, dgrp_t group);
extern blk_t ext2fs_inode_data_blocks(ext2_filsys fs,