zfs_dsl_dir
struct zfs_dsl_dir *dir; /* containing parent */
typedef STAILQ_HEAD(zfs_dsl_dir_list, zfs_dsl_dir) zfs_dsl_dir_list_t;
struct zfs_dsl_dir *parent;
STAILQ_ENTRY(zfs_dsl_dir) next;
typedef struct zfs_dsl_dir zfs_dsl_dir_t;