ext2_count_free_inodes
extern unsigned long ext2_count_free_inodes (struct super_block *);
int avefreei = ext2_count_free_inodes(sb) / ngroups;
ext2_count_free_inodes(sb), GFP_KERNEL);
es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
buf->f_ffree = ext2_count_free_inodes(sb);