nilfs_iget_locked
cpfile = nilfs_iget_locked(sb, NULL, NILFS_CPFILE_INO);
dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO);
ifile = nilfs_iget_locked(sb, root, NILFS_IFILE_INO);
inode = nilfs_iget_locked(sb, root, ino);
struct inode *nilfs_iget_locked(struct super_block *sb, struct nilfs_root *root,
sufile = nilfs_iget_locked(sb, NULL, NILFS_SUFILE_INO);