text: #ifndef _MULTIPATH_H
  #define _MULTIPATH_H
  
  struct multipath_info {
  	mdk_rdev_t	*rdev;
  };
  
  struct multipath_private_data {
  	mddev_t			*mddev;
  	struct multipath_info	*multipaths;
  	int			raid_disks;
  	int			working_disks;
  	spinlock_t		device_lock;
  	struct list_head	retry_list;
  
  	mempool_t		*pool;
  };
  
  typedef struct multipath_private_data multipath_conf_t;
  
  /*
   * this is our 'private' 'collective' MULTIPATH buffer head.
   * it contains information about what kind of IO operations were started
   * for this MULTIPATH operation, and about their status:
   */
  
  struct multipath_bh {
  	mddev_t			*mddev;
  	struct bio		*master_bio;
  	struct bio		bio;
  	int			path;
  	struct list_head	retry_list;
  };
  #endif
  