struct disk_part_tbl {
	struct rcu_head rcu_head;
	int len;
	struct hd_struct *last_lookup;
	struct hd_struct *part[];
};

struct gendisk {
	/* major, first_minor and minors are input parameters only,
	 * don't use directly.  Use disk_devt() and disk_max_parts().
	 */
	int major;			/* major number of driver */
	int first_minor;
	int minors;                     /* maximum number of minors, =1 for
                                         * disks that can't be partitioned. */

	char disk_name[DISK_NAME_LEN];	/* name of major driver */
	char *(*nodename)(struct gendisk *gd);
	/* Array of pointers to partitions indexed by partno.
	 * Protected with matching bdev lock but stat and other
	 * non-critical accesses use RCU.  Always access through
	 * helpers.
	 */
	struct disk_part_tbl *part_tbl;
	struct hd_struct part0;

	struct block_device_operations *fops;
	struct request_queue *queue;
	void *private_data;

	int flags;
	struct device *driverfs_dev;  // FIXME: remove
	struct kobject *slave_dir;

	struct timer_rand_state *random;

	atomic_t sync_io;		/* RAID */
	struct work_struct async_notify;
#ifdef  CONFIG_BLK_DEV_INTEGRITY
	struct blk_integrity *integrity;
#endif
	int node_id;
};