diff --git a/caching/metadata.cc b/caching/metadata.cc
index 5985080..f9c02f2 100644
--- a/caching/metadata.cc
+++ b/caching/metadata.cc
@@ -1,17 +1,80 @@
 #include "caching/metadata.h"
+#include "persistent-data/space-maps/core.h"
 
 using namespace caching;
 
 //----------------------------------------------------------------
 
-metadata::metadata(block_manager<>::ptr bm, open_type ot)
-{
+namespace {
+	using namespace superblock_detail;
 
-}
+	unsigned const METADATA_CACHE_SIZE = 1024;
 
-metadata::metadata(block_manager<>::ptr bm, block_address metadata_snap)
-{
+	// FIXME: duplication
+	transaction_manager::ptr
+	open_tm(block_manager<>::ptr bm) {
+		space_map::ptr sm(new core_map(bm->get_nr_blocks()));
+		sm->inc(SUPERBLOCK_LOCATION);
+		transaction_manager::ptr tm(new transaction_manager(bm, sm));
+		return tm;
+	}
 
+	void
+	copy_space_maps(space_map::ptr lhs, space_map::ptr rhs) {
+		for (block_address b = 0; b < rhs->get_nr_blocks(); b++) {
+			uint32_t count = rhs->get_count(b);
+			if (count > 0)
+				lhs->set_count(b, rhs->get_count(b));
+		}
+	}
+
+	void init_superblock(superblock &sb) {
+#if 0
+		sb.magic_ = SUPERBLOCK_MAGIC;
+		sb.version_ = 1;
+		sb.data_mapping_root_ = mappings_->get_root();
+		sb.device_details_root_ = details_->get_root();
+		sb.data_block_size_ = data_block_size;
+		sb.metadata_block_size_ = MD_BLOCK_SIZE;
+		sb.metadata_nr_blocks_ = tm_->get_bm()->get_nr_blocks();
+#endif
+	}
+}
+
+//----------------------------------------------------------------
+
+metadata::metadata(block_manager<>::ptr bm, open_type ot)
+{
+	switch (ot) {
+	case OPEN:
+		throw runtime_error("not implemented");
+		break;
+
+	case CREATE:
+		tm_ = open_tm(bm);
+		space_map::ptr core = tm_->get_sm();
+		metadata_sm_ = create_metadata_sm(tm_, tm_->get_bm()->get_nr_blocks());
+		copy_space_maps(metadata_sm_, core);
+		tm_->set_sm(metadata_sm_);
+
+		mappings_ = mapping_array::ptr(new mapping_array(tm_, mapping_array::ref_counter()));
+//		hints_ = hint_array::ptr(new hint_array(tm_));
+
+		::memset(&sb_, 0, sizeof(sb_));
+		init_superblock(sb_);
+	}
+}
+
+void
+metadata::commit()
+{
+	metadata_sm_->commit();
+	metadata_sm_->copy_root(&sb_.metadata_space_map_root, sizeof(sb_.metadata_space_map_root));
+	sb_.mapping_root = mappings_->get_root();
+
+	write_ref superblock = tm_->get_bm()->superblock_zero(SUPERBLOCK_LOCATION, superblock_validator());
+	superblock_disk *disk = reinterpret_cast<superblock_disk *>(superblock.data().raw());
+	superblock_traits::pack(sb_, *disk);
 }
 
 //----------------------------------------------------------------
diff --git a/caching/metadata.h b/caching/metadata.h
index e94bea2..7b956a5 100644
--- a/caching/metadata.h
+++ b/caching/metadata.h
@@ -26,7 +26,8 @@ namespace caching {
 		typedef boost::shared_ptr<metadata> ptr;
 
 		metadata(block_manager<>::ptr bm, open_type ot);
-		metadata(block_manager<>::ptr bm, block_address metadata_snap);
+
+		void commit();
 
 		typedef persistent_data::transaction_manager tm;
 		tm::ptr tm_;
diff --git a/caching/restore_emitter.cc b/caching/restore_emitter.cc
index 499f13b..efca1de 100644
--- a/caching/restore_emitter.cc
+++ b/caching/restore_emitter.cc
@@ -12,27 +12,70 @@ namespace {
 	class restorer : public emitter {
 	public:
 		restorer(metadata::ptr md)
-			: md_(md) {
+			: in_superblock_(false),
+			  md_(md) {
+		}
+
+		virtual ~restorer() {
 		}
 
 		virtual void begin_superblock(std::string const &uuid,
 					      pd::block_address block_size,
 					      pd::block_address nr_cache_blocks,
 					      std::string const &policy) {
+
+			superblock &sb = md_->sb_;
+
+			sb.flags = 0;
+			memset(sb.uuid, 0, sizeof(sb.uuid));
+			sb.magic = caching::superblock_detail::SUPERBLOCK_MAGIC;
+			sb.version = 0; // FIXME: fix
+			// strncpy(sb.policy_name, policy.c_str(), sizeof(sb.policy_name));
+			memset(sb.policy_version, 0, sizeof(sb.policy_version));
+			sb.policy_hint_size = 0; // FIXME: fix
+
+			memset(sb.metadata_space_map_root, 0, sizeof(sb.metadata_space_map_root));
+			sb.mapping_root = 0;
+			sb.hint_root = 0;
+
+			sb.discard_root = 0;
+			sb.discard_block_size = 0;
+			sb.discard_nr_blocks = 0;
+
+			sb.data_block_size = block_size;
+			sb.metadata_block_size = 0;
+			sb.cache_blocks = nr_cache_blocks;
+
+			sb.compat_flags = 0;
+			sb.compat_ro_flags = 0;
+			sb.incompat_flags = 0;
+
+			sb.read_hits = 0;
+			sb.read_misses = 0;
+			sb.write_hits = 0;
+			sb.write_misses = 0;
 		}
 
 		virtual void end_superblock() {
+			md_->commit();
 		}
 
 		virtual void begin_mappings() {
+			// noop
 		}
 
 		virtual void end_mappings() {
+			// noop
 		}
 
 		virtual void mapping(pd::block_address cblock,
 				     pd::block_address oblock,
 				     bool dirty) {
+			mapping_array_detail::mapping m;
+			m.oblock_ = oblock;
+			m.flags_ = 0;
+
+			md_->mappings_->set(cblock, m);
 		}
 
 		virtual void begin_hints() {
@@ -46,6 +89,7 @@ namespace {
 		}
 
 	private:
+		bool in_superblock_;
 		metadata::ptr md_;
 	};
 }
diff --git a/persistent-data/data-structures/array.h b/persistent-data/data-structures/array.h
index f69d627..9b4c9bd 100644
--- a/persistent-data/data-structures/array.h
+++ b/persistent-data/data-structures/array.h
@@ -128,9 +128,9 @@ namespace persistent_data {
 
 		typedef boost::shared_ptr<array<ValueTraits> > ptr;
 		typedef typename ValueTraits::value_type value_type;
+		typedef typename ValueTraits::ref_counter ref_counter;
 
-		array(tm_ptr tm,
-		      typename ValueTraits::ref_counter rc)
+		array(tm_ptr tm, ref_counter rc)
 			: tm_(tm),
 			  entries_per_block_(rblock::calc_max_entries()),
 			  nr_entries_(0),
@@ -140,8 +140,7 @@ namespace persistent_data {
 			  validator_(new block_manager<>::noop_validator()) {
 		}
 
-		array(tm_ptr tm,
-		      typename ValueTraits::ref_counter rc,
+		array(tm_ptr tm, ref_counter rc,
 		      block_address root,
 		      unsigned nr_entries)
 			: tm_(tm),