static struct inode *ext4_nfs_get_inode(struct super_block *sb,
					u64 ino, u32 generation)
{
	struct inode *inode;

	if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
		return ERR_PTR(-ESTALE);
	if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
		return ERR_PTR(-ESTALE);

	/* iget isn't really right if the inode is currently unallocated!!
	 *
	 * ext4_read_inode will return a bad_inode if the inode had been
	 * deleted, so we should be safe.
	 *
	 * Currently we don't know the generation for parent directory, so
	 * a generation of 0 means "accept any"
	 */
	inode = ext4_iget(sb, ino);
	if (IS_ERR(inode))
		return ERR_CAST(inode);
	if (generation && inode->i_generation != generation) {
		iput(inode);
		return ERR_PTR(-ESTALE);
	}

	return inode;
}
static struct inode *ext4_nfs_get_inode(struct super_block *sb,
					u64 ino, u32 generation)
{
	struct inode *inode;

	if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
		return ERR_PTR(-ESTALE);
	if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
		return ERR_PTR(-ESTALE);

	 
	inode = ext4_iget(sb, ino);
	if (IS_ERR(inode))
		return ERR_CAST(inode);
	if (generation && inode->i_generation != generation) {
		iput(inode);
		return ERR_PTR(-ESTALE);
	}

	return inode;
}