boolean_t dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
uint64_t blk_birth);
uint64_t dsl_dataset_prev_snap_txg(dsl_dataset_t *ds);
boolean_t dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
uint64_t blk_birth);
uint64_t dsl_dataset_prev_snap_txg(dsl_dataset_t *ds);