thin_restore works (well thin_repair thinks it does).

Makefile

@@ -18,9 +18,14 @@ SOURCE=\
 	transaction_manager.cc \
 	xml_format.cc
 
+PROGRAM_SOURCE=\
+	thin_dump.cc \
+	thin_repair.cc \
+	thin_restore.cc
+
 OBJECTS=$(subst .cc,.o,$(SOURCE))
 TOP_DIR:=$(PWD)
-CPPFLAGS=-Wall -g -I$(TOP_DIR) -O8
+CPPFLAGS=-Wall -g -I$(TOP_DIR)
 #CPPFLAGS=-Wall -std=c++0x -g -I$(TOP_DIR)
 LIBS=-lstdc++ -lboost_program_options -lexpat
 
@@ -50,3 +55,4 @@ thin_repair: $(OBJECTS) thin_repair.o
 include unit-tests/Makefile.in
 include $(subst .cc,.d,$(SOURCE))
 include $(subst .cc,.d,$(TEST_SOURCE))
+include $(subst .cc,.d,$(PROGRAM_SOURCE))

block.h

@@ -200,6 +200,12 @@ namespace persistent_data {
 		typedef std::map<block_address, std::pair<lock_type, unsigned> > held_map;
 		mutable held_map held_locks_;
 	};
+
+	// A little utility to help build validators
+	inline block_manager<>::validator::ptr
+	mk_validator(block_manager<>::validator *v) {
+		return block_manager<>::validator::ptr(v);
+	}
 }
 
 #include "block.tcc"

block.tcc

@@ -8,6 +8,7 @@
 
 #include <boost/bind.hpp>
 #include <stdexcept>
+#include <sstream>
 
 using namespace boost;
 using namespace persistent_data;
@@ -20,7 +21,8 @@ block_io<BlockSize>::block_io(std::string const &path, block_address nr_blocks,
 	: nr_blocks_(nr_blocks),
 	  writeable_(writeable)
 {
-	fd_ = ::open(path.c_str(), writeable ? (O_RDWR | O_CREAT) : O_RDONLY, 0666);
+	// fd_ = ::open(path.c_str(), writeable ? (O_RDWR | O_CREAT) : O_RDONLY, 0666);
+	fd_ = ::open(path.c_str(), writeable ? O_RDWR : O_RDONLY, 0666);
 	if (fd_ < 0)
 		throw std::runtime_error("couldn't open file");
 }
@@ -75,8 +77,17 @@ block_io<BlockSize>::write_buffer(block_address location, const_buffer &buffer)
 		}
 	} while (remaining && ((n > 0) || (n == EINTR) || (n == EAGAIN)));
 
-	if (n < 0)
+	if (n < 0) {
-		throw std::runtime_error("write failed");
+		std::ostringstream out;
+		out << "write failed to block " << location
+		    << ", block size = " << BlockSize
+		    << ", remaining = " << remaining
+		    << ", n = " << n
+		    << ", errno = " << errno
+		    << ", fd_ = " << fd_
+		    << std::endl;
+		throw std::runtime_error(out.str());
+	}
 }
 
 //----------------------------------------------------------------
@@ -277,6 +288,7 @@ block_manager<BlockSize>::superblock(block_address location,
 	if (cached_block) {
 		(*cached_block)->check_write_lockable();
 		(*cached_block)->bt_ = BT_SUPERBLOCK;
+		(*cached_block)->validator_ = v;
 		return write_ref(*this, *cached_block);
 	}
 
@@ -297,10 +309,13 @@ block_manager<BlockSize>::superblock_zero(block_address location,
 	if (cached_block) {
 		(*cached_block)->check_write_lockable();
 		memset(&(*cached_block)->data_, 0, BlockSize);
+		(*cached_block)->validator_ = v;
 		return write_ref(*this, *cached_block);
 	}
 
-	block_ptr b(new block(io_, location, BT_SUPERBLOCK, v, true));
+	block_ptr b(new block(io_, location, BT_SUPERBLOCK,
+			      mk_validator(new noop_validator), true));
+	b->validator_ = v;
 	cache_.insert(b);
 	return write_ref(*this, b);
 }

btree.h

@@ -177,11 +177,7 @@ namespace persistent_data {
 				: tm_(tm) {
 			}
 
-			void step(block_address b) {
+			void step(block_address b);
-				spine_.push_back(tm_->read_lock(b));
-				if (spine_.size() > 2)
-					spine_.pop_front();
-			}
 
 			template <typename ValueTraits>
 			node_ref<ValueTraits> get_node() {
@@ -203,17 +199,7 @@ namespace persistent_data {
 			}
 
 			// true if the children of the shadow need incrementing
-			bool step(block_address b) {
+			bool step(block_address b);
-				pair<write_ref, bool> p = tm_->shadow(b);
-				try {
-					step(p.first);
-				} catch (...) {
-					tm_->get_sm()->dec(p.first.get_location());
-					throw;
-				}
-				return p.second;
-			}
-
 			void step(transaction_manager::write_ref b) {
 				spine_.push_back(b);
 				if (spine_.size() == 1)

btree.tcc

@@ -1,4 +1,6 @@
 #include "btree.h"
+
+#include "checksum.h"
 #include "transaction_manager.h"
 
 #include <iostream>
@@ -9,6 +11,62 @@ using namespace std;
 
 //----------------------------------------------------------------
 
+namespace {
+	struct btree_node_validator : public block_manager<>::validator {
+		virtual void check(block_manager<>::const_buffer &b, block_address location) const {
+			disk_node const *data = reinterpret_cast<disk_node const *>(&b);
+			node_header const *n = &data->header;
+			crc32c sum(BTREE_CSUM_XOR);
+			sum.append(&n->flags, MD_BLOCK_SIZE - sizeof(uint32_t));
+			if (sum.get_sum() != to_cpu<uint32_t>(n->csum))
+				throw runtime_error("bad checksum in btree node");
+
+			if (to_cpu<uint64_t>(n->blocknr) != location)
+				throw runtime_error("bad block nr in btree node");
+		}
+
+		virtual void prepare(block_manager<>::buffer &b, block_address location) const {
+			disk_node *data = reinterpret_cast<disk_node *>(&b);
+			node_header *n = &data->header;
+			n->blocknr = to_disk<base::__le64, uint64_t>(location);
+
+			crc32c sum(BTREE_CSUM_XOR);
+			sum.append(&n->flags, MD_BLOCK_SIZE - sizeof(uint32_t));
+			n->csum = to_disk<base::__le32>(sum.get_sum());
+		}
+	};
+
+	block_manager<>::validator::ptr
+	btree_validator() {
+		return block_manager<>::validator::ptr(new btree_node_validator);
+	}
+}
+
+//----------------------------------------------------------------
+
+inline void
+ro_spine::step(block_address b)
+{
+	spine_.push_back(tm_->read_lock(b, btree_validator()));
+	if (spine_.size() > 2)
+		spine_.pop_front();
+}
+
+inline bool
+shadow_spine::step(block_address b)
+{
+	pair<write_ref, bool> p = tm_->shadow(b, btree_validator());
+	try {
+		step(p.first);
+	} catch (...) {
+		tm_->get_sm()->dec(p.first.get_location());
+		throw;
+	}
+	return p.second;
+}
+
+//----------------------------------------------------------------
+
 template <typename ValueTraits>
 node_ref<ValueTraits>::node_ref(block_address location, disk_node *raw)
 	: location_(location),
@@ -291,7 +349,7 @@ btree(typename transaction_manager::ptr tm,
 {
 	using namespace btree_detail;
 
-	write_ref root = tm_->new_block();
+	write_ref root = tm_->new_block(btree_validator());
 
 	leaf_node n = to_node<ValueTraits>(root);
 	n.set_type(btree_detail::LEAF);
@@ -511,13 +569,13 @@ split_beneath(btree_detail::shadow_spine &spine,
 	node_type type;
 	unsigned nr_left, nr_right;
 
-	write_ref left = tm_->new_block();
+	write_ref left = tm_->new_block(btree_validator());
 	node_ref<ValueTraits> l = to_node<ValueTraits>(left);
 	l.set_nr_entries(0);
 	l.set_max_entries();
 	l.set_value_size(sizeof(typename ValueTraits::disk_type));
 
-	write_ref right = tm_->new_block();
+	write_ref right = tm_->new_block(btree_validator());
 	node_ref<ValueTraits> r = to_node<ValueTraits>(right);
 	r.set_nr_entries(0);
 	r.set_max_entries();
@@ -570,7 +628,7 @@ split_sibling(btree_detail::shadow_spine &spine,
 	node_ref<ValueTraits> l = spine.template get_node<ValueTraits>();
 	block_address left = spine.get_block();
 
-	write_ref right = tm_->new_block();
+	write_ref right = tm_->new_block(btree_validator());
 	node_ref<ValueTraits> r = to_node<ValueTraits>(right);
 
 	unsigned nr_left = l.get_nr_entries() / 2;

btree_checker.h

@@ -5,7 +5,6 @@
 
 #include "checksum.h"
 #include "error_set.h"
-#include "hex_dump.h"
 
 #include <sstream>
 #include <map>
@@ -170,7 +169,7 @@ namespace persistent_data {
 				std::ostringstream out;
 				out << "checksum error for block " << n.get_block_nr()
 				    << ", sum was " << sum.get_sum()
-				    << ", expected " << n.get_checksum();
+				    << ", on disk " << n.get_checksum();
 				errs_->add_child(out.str());
 				throw runtime_error(out.str());
 			}

metadata.cc

@@ -19,8 +19,27 @@ namespace {
         uint32_t const VERSION = 1;
 	unsigned const METADATA_CACHE_SIZE = 1024;
         unsigned const SECTOR_TO_BLOCK_SHIFT = 3;
+	uint32_t const SUPERBLOCK_CSUM_SEED = 160774;
 
-	block_address get_nr_blocks(string const &path) {
+	struct superblock_validator : public block_manager<>::validator {
+		virtual void check(block_manager<>::const_buffer &b, block_address location) const {
+			superblock_disk const *sbd = reinterpret_cast<superblock_disk const *>(&b);
+			crc32c sum(SUPERBLOCK_CSUM_SEED);
+			sum.append(&sbd->flags_, MD_BLOCK_SIZE - sizeof(uint32_t));
+			if (sum.get_sum() != to_cpu<uint32_t>(sbd->csum_))
+				throw runtime_error("bad checksum in superblock");
+		}
+
+		virtual void prepare(block_manager<>::buffer &b, block_address location) const {
+			superblock_disk *sbd = reinterpret_cast<superblock_disk *>(&b);
+			crc32c sum(SUPERBLOCK_CSUM_SEED);
+			sum.append(&sbd->flags_, MD_BLOCK_SIZE - sizeof(uint32_t));
+			sbd->csum_ = to_disk<base::__le32>(sum.get_sum());
+		}
+	};
+
+	block_address
+	get_nr_blocks(string const &path) {
 		struct stat info;
 		block_address nr_blocks;
 
@@ -52,55 +71,93 @@ namespace {
 	}
 
 	transaction_manager::ptr
-	open_tm(string const &dev_path) {
+	open_tm(string const &dev_path, bool writeable) {
 		block_address nr_blocks = get_nr_blocks(dev_path);
-		block_manager<>::ptr bm(new block_manager<>(dev_path, nr_blocks, 8));
+		block_manager<>::ptr bm(new block_manager<>(dev_path, nr_blocks, 1, writeable));
 		space_map::ptr sm(new core_map(nr_blocks));
+		sm->inc(SUPERBLOCK_LOCATION);
 		transaction_manager::ptr tm(new transaction_manager(bm, sm));
 		return tm;
 	}
 
-	superblock read_superblock(block_manager<>::ptr bm) {
+	superblock
+	read_superblock(block_manager<>::ptr bm) {
 		superblock sb;
-		block_manager<>::read_ref r = bm->read_lock(SUPERBLOCK_LOCATION);
+		block_manager<>::read_ref r = bm->read_lock(SUPERBLOCK_LOCATION,
+							    mk_validator(new superblock_validator));
 		superblock_disk const *sbd = reinterpret_cast<superblock_disk const *>(&r.data());
-
-		crc32c sum(160774); // FIXME: magic number
-		sum.append(&sbd->flags_, MD_BLOCK_SIZE - sizeof(uint32_t));
-		if (sum.get_sum() != to_cpu<uint32_t>(sbd->csum_)) {
-			ostringstream out;
-			out << "bad checksum in superblock, calculated "
-			    << sum.get_sum()
-			    << ", superblock contains " << to_cpu<uint32_t>(sbd->csum_);
-			throw runtime_error(out.str());
-		}
-
 		superblock_traits::unpack(*sbd, sb);
 		return sb;
 	}
+
+	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));
+		}
+	}
 }
 
 //----------------------------------------------------------------
 
-metadata::metadata(std::string const &dev_path, open_type ot)
+metadata::metadata(std::string const &dev_path, open_type ot,
-	: tm_(open_tm(dev_path)),
+		   sector_t data_block_size, block_address nr_data_blocks)
-	  sb_(read_superblock(tm_->get_bm())),
-	  metadata_sm_(open_metadata_sm(tm_, static_cast<void *>(&sb_.metadata_space_map_root_))),
-	  data_sm_(open_disk_sm(tm_, static_cast<void *>(&sb_.data_space_map_root_))),
-	  details_(new detail_tree(tm_, sb_.device_details_root_, device_details_traits::ref_counter())),
-	  mappings_top_level_(new dev_tree(tm_, sb_.data_mapping_root_, mtree_ref_counter(tm_))),
-	  mappings_(new mapping_tree(tm_, sb_.data_mapping_root_, block_time_ref_counter(data_sm_)))
 {
-	tm_->set_sm(open_metadata_sm(tm_, sb_.metadata_space_map_root_));
+	switch (ot) {
-}
+	case OPEN:
+		tm_ = open_tm(dev_path, false);
+		sb_ = read_superblock(tm_->get_bm());
+		metadata_sm_ = open_metadata_sm(tm_, &sb_.metadata_space_map_root_);
+		tm_->set_sm(metadata_sm_);
+
+		data_sm_ = open_disk_sm(tm_, static_cast<void *>(&sb_.data_space_map_root_));
+		details_ = detail_tree::ptr(new detail_tree(tm_, sb_.device_details_root_, device_details_traits::ref_counter()));
+		mappings_top_level_ = dev_tree::ptr(new dev_tree(tm_, sb_.data_mapping_root_, mtree_ref_counter(tm_)));
+		mappings_ = mapping_tree::ptr(new mapping_tree(tm_, sb_.data_mapping_root_, block_time_ref_counter(data_sm_)));
+		break;
+
+	case CREATE:
+		tm_ = open_tm(dev_path, true);
+		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_);
+
+		data_sm_ = create_disk_sm(tm_, nr_data_blocks);
+		details_ = detail_tree::ptr(new detail_tree(tm_, device_details_traits::ref_counter()));
+		mappings_ = mapping_tree::ptr(new mapping_tree(tm_, block_time_ref_counter(data_sm_)));
+		mappings_top_level_ = dev_tree::ptr(new dev_tree(tm_, mappings_->get_root(), mtree_ref_counter(tm_)));
 
-#if 0
 		::memset(&sb_, 0, sizeof(sb_));
-	sb_.data_mapping_root_ = mappings_.get_root();
+		sb_.magic_ = SUPERBLOCK_MAGIC;
-	sb_.device_details_root_ = details_.get_root();
+		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
+
+		break;
+	}
+}
+
+namespace {
+	void print_superblock(superblock const &sb) {
+		using namespace std;
+
+		cerr << "superblock " << sb.csum_ << endl
+		     << "flags " << sb.flags_ << endl
+		     << "blocknr " << sb.blocknr_ << endl
+		     << "transaction id " << sb.trans_id_ << endl
+		     << "data mapping root " << sb.data_mapping_root_ << endl
+		     << "details root " << sb.device_details_root_ << endl
+		     << "data block size " << sb.data_block_size_ << endl
+		     << "metadata block size " << sb.metadata_block_size_ << endl
+		     << "metadata nr blocks " << sb.metadata_nr_blocks_ << endl
+			;
+	}
+}
 
 void
 metadata::commit()
@@ -108,9 +165,16 @@ metadata::commit()
 	sb_.data_mapping_root_ = mappings_->get_root();
 	sb_.device_details_root_ = details_->get_root();
 
-	// FIXME: commit and copy the space map roots
+	data_sm_->commit();
+	data_sm_->copy_root(&sb_.data_space_map_root_, sizeof(sb_.data_space_map_root_));
 
-	write_ref superblock = tm_->get_bm()->superblock(SUPERBLOCK_LOCATION);
+	metadata_sm_->commit();
+	metadata_sm_->copy_root(&sb_.metadata_space_map_root_, sizeof(sb_.metadata_space_map_root_));
+	print_superblock(sb_);
+
+	superblock_validator v;
+	write_ref superblock = tm_->get_bm()->superblock_zero(SUPERBLOCK_LOCATION,
+							      mk_validator(new superblock_validator()));
         superblock_disk *disk = reinterpret_cast<superblock_disk *>(superblock.data());
 	superblock_traits::pack(sb_, *disk);
 }

metadata.h

@@ -129,7 +129,9 @@ namespace thin_provisioning {
 			OPEN
 		};
 
-		metadata(std::string const &dev_path, open_type ot);
+		metadata(std::string const &dev_path, open_type ot,
+			 sector_t data_block_size = 128,
+			 block_address nr_data_blocks = 0); // Only used if CREATE
 
 		void commit();
 

metadata_checker.cc

@@ -134,10 +134,11 @@ thin_provisioning::metadata_check(metadata::ptr md)
 	mapping_validator::ptr mv(new mapping_validator(metadata_counter,
 							data_counter));
 	md->mappings_->visit(mv);
-	set<uint64_t> const &mapped_devs = mv->get_devices();
 
+	set<uint64_t> const &mapped_devs = mv->get_devices();
 	details_validator::ptr dv(new details_validator(metadata_counter));
 	md->details_->visit(dv);
+
 	set<uint64_t> const &details_devs = dv->get_devices();
 
 	for (set<uint64_t>::const_iterator it = mapped_devs.begin(); it != mapped_devs.end(); ++it)
@@ -150,6 +151,7 @@ thin_provisioning::metadata_check(metadata::ptr md)
 
 	metadata_counter.inc(SUPERBLOCK_LOCATION);
 	md->metadata_sm_->check(metadata_counter);
+
 	md->data_sm_->check(metadata_counter);
 	errors->add_child(check_ref_counts("Errors in metadata block reference counts",
 					   metadata_counter, md->metadata_sm_));

metadata_disk_structures.h

@@ -65,6 +65,7 @@ namespace thin_provisioning {
 		__le64 metadata_nr_blocks_;
 
 		__le32 compat_flags_;
+		__le32 compat_ro_flags_;
 		__le32 incompat_flags_;
 	} __attribute__ ((packed));
 
@@ -97,6 +98,7 @@ namespace thin_provisioning {
 		uint64_t metadata_nr_blocks_;
 
 		uint32_t compat_flags_;
+		uint32_t compat_ro_flags_;
 		uint32_t incompat_flags_;
 	};
 

restore_emitter.cc

@@ -38,7 +38,6 @@ namespace {
 				throw runtime_error("missing superblock");
 
 			md_->commit();
-
 			in_superblock_ = false;
 		}
 
@@ -64,7 +63,6 @@ namespace {
 							block_time_ref_counter(md_->data_sm_)));
 			md_->mappings_top_level_->insert(key, new_tree->get_root());
 			md_->mappings_->set_root(md_->mappings_top_level_->get_root()); // FIXME: ugly
-
 			current_device_ = optional<uint32_t>(dev);
 		}
 
@@ -99,12 +97,14 @@ namespace {
 			bt.time_ = time;
 			md_->mappings_->insert(key, bt);
 			md_->mappings_top_level_->set_root(md_->mappings_->get_root());
+			md_->data_sm_->inc(data_block);
 		}
 
 	private:
 		bool device_exists(thin_dev_t dev) const {
 			uint64_t key[1] = {dev};
-			return md_->details_->lookup(key);
+			detail_tree::maybe_value v = md_->details_->lookup(key);
+			return v;
 		}
 
 		metadata::ptr md_;

space_map_disk.cc

@@ -1,5 +1,6 @@
 #include "space_map_disk.h"
 
+#include "checksum.h"
 #include "endian_utils.h"
 #include "math_utils.h"
 #include "space_map_disk_structures.h"
@@ -14,6 +15,35 @@ using namespace sm_disk_detail;
 //----------------------------------------------------------------
 
 namespace {
+	uint64_t const BITMAP_CSUM_XOR = 240779;
+
+	struct bitmap_block_validator : public block_manager<>::validator {
+		virtual void check(block_manager<>::const_buffer &b, block_address location) const {
+			bitmap_header const *data = reinterpret_cast<bitmap_header const *>(&b);
+			crc32c sum(BITMAP_CSUM_XOR);
+			sum.append(&data->not_used, MD_BLOCK_SIZE - sizeof(uint32_t));
+			if (sum.get_sum() != to_cpu<uint32_t>(data->csum))
+				throw runtime_error("bad checksum in space map bitmap");
+
+			if (to_cpu<uint64_t>(data->blocknr) != location)
+				throw runtime_error("bad block nr in space map bitmap");
+		}
+
+		virtual void prepare(block_manager<>::buffer &b, block_address location) const {
+			bitmap_header *data = reinterpret_cast<bitmap_header *>(&b);
+			data->blocknr = to_disk<base::__le64, uint64_t>(location);
+
+			crc32c sum(BITMAP_CSUM_XOR);
+			sum.append(&data->not_used, MD_BLOCK_SIZE - sizeof(uint32_t));
+			data->csum = to_disk<base::__le32>(sum.get_sum());
+		}
+	};
+
+	block_manager<>::validator::ptr
+	bitmap_validator() {
+		return block_manager<>::validator::ptr(new bitmap_block_validator());
+	}
+
 	class bitmap {
 	public:
 		typedef transaction_manager::read_ref read_ref;
@@ -64,16 +94,16 @@ namespace {
 			}
 		}
 
-		unsigned find_free(unsigned end) {
+		boost::optional<unsigned> find_free(unsigned begin, unsigned end) {
-			for (unsigned i = ie_.none_free_before_; i < end; i++) {
+			for (unsigned i = max(begin, ie_.none_free_before_); i < end; i++) {
 				if (lookup(i) == 0) {
 					insert(i, 1);
 					ie_.none_free_before_ = i + 1;
-					return i;
+					return boost::optional<unsigned>(i);
 				}
 			}
 
-			throw std::runtime_error("no free entry in bitmap");
+			return boost::optional<unsigned>();
 		}
 
 		index_entry const &get_ie() const {
@@ -213,21 +243,24 @@ namespace {
 		}
 
 		block_address new_block() {
-			// silly to always start searching from the
+			// FIXME: silly to always start searching from the
 			// beginning.
 			block_address nr_indexes = div_up<block_address>(nr_blocks_, entries_per_block_);
 			for (block_address index = 0; index < nr_indexes; index++) {
 				index_entry ie = find_ie(index);
 
 				bitmap bm(tm_, ie);
-				block_address b = bm.find_free((index == nr_indexes - 1) ?
+				optional<unsigned> maybe_b = bm.find_free(0, (index == nr_indexes - 1) ?
 							  nr_blocks_ % entries_per_block_ : entries_per_block_);
-				save_ie(b, bm.get_ie());
+				if (maybe_b) {
+					block_address b = *maybe_b;
+					save_ie(index, bm.get_ie());
 					nr_allocated_++;
 					b = (index * entries_per_block_) + b;
 					assert(get_count(b) == 1);
 					return b;
 				}
+			}
 
 			throw runtime_error("out of space");
 		}
@@ -242,9 +275,9 @@ namespace {
 			block_address bitmap_count = div_up<block_address>(nr_blocks, entries_per_block_);
 			block_address old_bitmap_count = div_up<block_address>(nr_blocks_, entries_per_block_);
 			for (block_address i = old_bitmap_count; i < bitmap_count; i++) {
-				write_ref wr = tm_->new_block();
+				write_ref wr = tm_->new_block(bitmap_validator());
 
-				struct index_entry ie;
+				index_entry ie;
 				ie.blocknr_ = wr.get_location();
 				ie.nr_free_ = i == (bitmap_count - 1) ?
 					(nr_blocks % entries_per_block_) : entries_per_block_;
@@ -324,7 +357,7 @@ namespace {
 			index_entry ie = find_ie(b / entries_per_block_);
 			bitmap bm(tm_, ie);
 			bm.insert(b % entries_per_block_, n);
-			save_ie(b, bm.get_ie());
+			save_ie(b / entries_per_block_, bm.get_ie());
 		}
 
 		ref_t lookup_ref_count(block_address b) const {
@@ -436,6 +469,7 @@ namespace {
 			v.nr_allocated_ = sm_disk_base::get_nr_allocated();
 			v.bitmap_root_ = bitmaps_.get_root();
 			v.ref_count_root_ = sm_disk_base::get_ref_count_root();
+
 			sm_root_traits::pack(v, d);
 			::memcpy(dest, &d, sizeof(d));
 		}
@@ -477,8 +511,8 @@ namespace {
 
 		sm_metadata(transaction_manager::ptr tm)
 			: sm_disk_base(tm),
+			  bitmap_root_(tm->get_sm()->new_block()), // FIXME: add bitmap_index validator
 			  entries_(MAX_METADATA_BITMAPS) {
-			// FIXME: allocate a new bitmap root
 		}
 
 		sm_metadata(transaction_manager::ptr tm,
@@ -505,6 +539,7 @@ namespace {
 			v.nr_allocated_ = sm_disk_base::get_nr_allocated();
 			v.bitmap_root_ = bitmap_root_;
 			v.ref_count_root_ = sm_disk_base::get_ref_count_root();
+
 			sm_root_traits::pack(v, d);
 			::memcpy(dest, &d, sizeof(d));
 		}
@@ -581,6 +616,14 @@ persistent_data::open_disk_sm(transaction_manager::ptr tm, void *root)
 	return checked_space_map::ptr(new sm_disk(tm, v));
 }
 
+checked_space_map::ptr
+persistent_data::create_metadata_sm(transaction_manager::ptr tm, block_address nr_blocks)
+{
+	checked_space_map::ptr sm(new sm_metadata(tm));
+	sm->extend(nr_blocks);
+	return sm;
+}
+
 checked_space_map::ptr
 persistent_data::open_metadata_sm(transaction_manager::ptr tm, void *root)
 {
@@ -589,6 +632,7 @@ persistent_data::open_metadata_sm(transaction_manager::ptr tm, void * root)
 
 	::memcpy(&d, root, sizeof(d));
 	sm_root_traits::unpack(d, v);
+
 	return checked_space_map::ptr(new sm_metadata(tm, v));
 }
 

space_map_disk.h

@@ -20,6 +20,9 @@ namespace persistent_data {
 	checked_space_map::ptr
 	open_disk_sm(transaction_manager::ptr tm, void *root);
 
+	checked_space_map::ptr
+	create_metadata_sm(transaction_manager::ptr tm, block_address nr_blocks);
+
 	checked_space_map::ptr
 	open_metadata_sm(transaction_manager::ptr tm, void *root);
 }

thin_restore.cc

@@ -18,16 +18,21 @@ namespace po = boost::program_options;
 
 namespace {
 	void restore(string const &backup_file, string const &dev) {
-		metadata::ptr md(new metadata(dev, metadata::CREATE));
+		// FIXME: hard coded
+		block_address const NR_BLOCKS = 100000;
+
+		metadata::ptr md(new metadata(dev, metadata::CREATE, 128, NR_BLOCKS));
 		emitter::ptr restorer = create_restore_emitter(md);
 		ifstream in(backup_file.c_str(), ifstream::in);
-		try {
+		// FIXME: 
+		//try {
 			parse_xml(in, restorer);
-
+#if 0
 		} catch (...) {
 			in.close();
 			throw;
 		}
+#endif
 	}
 
 	void usage(po::options_description const &desc) {

transaction_manager.cc

@@ -98,8 +98,8 @@ pair<transaction_manager::write_ref, bool>
 transaction_manager::shadow(block_address orig, validator v)
 {
 	if (is_shadow(orig) &&
-	    sm_->count_possibly_greater_than_one(orig))
+	    !sm_->count_possibly_greater_than_one(orig))
-		return make_pair(bm_->write_lock(orig), false);
+		return make_pair(bm_->write_lock(orig, v), false);
 
 	read_ref src = bm_->read_lock(orig, v);
 	write_ref dest = bm_->write_lock_zero(sm_->new_block(), v);

unit-tests/space_map_disk_t.cc

@@ -1,5 +1,5 @@
 #include "space_map_disk.h"
-#include "core_map.h"
+#include "space_map_core.h"
 
 #define BOOST_TEST_MODULE SpaceMapDiskTests
 #include <boost/test/included/unit_test.hpp>
@@ -11,13 +11,14 @@ using namespace persistent_data;
 //----------------------------------------------------------------
 
 namespace {
-	block_address const NR_BLOCKS = 10237;
+	block_address const NR_BLOCKS = 1000; // FIXME: bump up
 	block_address const SUPERBLOCK = 0;
+	block_address const MAX_LOCKS = 8;
 
 	transaction_manager::ptr
 	create_tm() {
 		block_manager<>::ptr bm(
-			new block_manager<>("./test.data", NR_BLOCKS));
+			new block_manager<>("./test.data", NR_BLOCKS, MAX_LOCKS, true));
 		space_map::ptr sm(new core_map(1024));
 		transaction_manager::ptr tm(
 			new transaction_manager(bm, sm));
@@ -26,27 +27,26 @@ namespace {
 
 	persistent_space_map::ptr
 	create_sm_disk() {
-		auto tm = create_tm();
+		transaction_manager::ptr tm = create_tm();
 		return persistent_data::create_disk_sm(tm, NR_BLOCKS);
 	}
+
+	persistent_space_map::ptr
+	create_sm_metadata() {
+		transaction_manager::ptr tm = create_tm();
+		return persistent_data::create_metadata_sm(tm, NR_BLOCKS);
+	}
 }
 
 //----------------------------------------------------------------
 
-BOOST_AUTO_TEST_CASE(reopen_an_sm)
+void _test_get_nr_blocks(space_map::ptr sm)
 {
-	auto sm = create_sm_disk();
-}
-
-BOOST_AUTO_TEST_CASE(test_get_nr_blocks)
-{
-	auto sm = create_sm_disk();
 	BOOST_CHECK_EQUAL(sm->get_nr_blocks(), NR_BLOCKS);
 }
 
-BOOST_AUTO_TEST_CASE(test_get_nr_free)
+void _test_get_nr_free(space_map::ptr sm)
 {
-	auto sm = create_sm_disk();
 	BOOST_CHECK_EQUAL(sm->get_nr_free(), NR_BLOCKS);
 
 	for (unsigned i = 0; i < NR_BLOCKS; i++) {
@@ -60,18 +60,16 @@ BOOST_AUTO_TEST_CASE(test_get_nr_free)
 	}
 }
 
-BOOST_AUTO_TEST_CASE(test_throws_no_space)
+void _test_throws_no_space(space_map::ptr sm)
 {
-	auto sm = create_sm_disk();
 	for (unsigned i = 0; i < NR_BLOCKS; i++)
 		sm->new_block();
 
 	BOOST_CHECK_THROW(sm->new_block(), std::runtime_error);
 }
 
-BOOST_AUTO_TEST_CASE(test_inc_and_dec)
+void _test_inc_and_dec(space_map::ptr sm)
 {
-	auto sm = create_sm_disk();
 	block_address b = 63;
 
 	for (unsigned i = 0; i < 50; i++) {
@@ -85,9 +83,8 @@ BOOST_AUTO_TEST_CASE(test_inc_and_dec)
 	}
 }
 
-BOOST_AUTO_TEST_CASE(test_not_allocated_twice)
+void _test_not_allocated_twice(space_map::ptr sm)
 {
-	auto sm = create_sm_disk();
 	block_address b = sm->new_block();
 
 	try {
@@ -97,16 +94,14 @@ BOOST_AUTO_TEST_CASE(test_not_allocated_twice)
 	}
 }
 
-BOOST_AUTO_TEST_CASE(test_set_count)
+void _test_set_count(space_map::ptr sm)
 {
-	auto sm = create_sm_disk();
 	sm->set_count(43, 5);
 	BOOST_CHECK_EQUAL(sm->get_count(43), 5);
 }
 
-BOOST_AUTO_TEST_CASE(test_set_effects_nr_allocated)
+void _test_set_affects_nr_allocated(space_map::ptr sm)
 {
-	auto sm = create_sm_disk();
 	for (unsigned i = 0; i < NR_BLOCKS; i++) {
 		sm->set_count(i, 1);
 		BOOST_CHECK_EQUAL(sm->get_nr_free(), NR_BLOCKS - i - 1);
@@ -118,24 +113,143 @@ BOOST_AUTO_TEST_CASE(test_set_effects_nr_allocated)
 	}
 }
 
-BOOST_AUTO_TEST_CASE(test_reopen)
+//----------------------------------------------------------------
+
+#if 0
+BOOST_AUTO_TEST_CASE(reopen_an_sm)
+{
+	space_map::ptr sm = create_sm_disk();
+}
+#endif
+
+BOOST_AUTO_TEST_CASE(test_disk_get_nr_blocks)
+{
+	space_map::ptr sm = create_sm_disk();
+	_test_get_nr_blocks(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_disk_get_nr_free)
+{
+	space_map::ptr sm = create_sm_disk();
+	_test_get_nr_free(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_disk_throws_no_space)
+{
+	space_map::ptr sm = create_sm_disk();
+	_test_throws_no_space(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_disk_inc_and_dec)
+{
+	space_map::ptr sm = create_sm_disk();
+	_test_inc_and_dec(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_disk_not_allocated_twice)
+{
+	space_map::ptr sm = create_sm_disk();
+	_test_not_allocated_twice(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_disk_set_count)
+{
+	space_map::ptr sm = create_sm_disk();
+	_test_set_count(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_disk_set_affects_nr_allocated)
+{
+	space_map::ptr sm = create_sm_disk();
+	_test_set_affects_nr_allocated(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_disk_reopen)
 {
 	unsigned char buffer[128];
 
 	{
-		auto sm = create_sm_disk();
+		persistent_space_map::ptr sm = create_sm_disk();
 		for (unsigned i = 0, step = 1; i < NR_BLOCKS; i += step, step++) {
 			sm->inc(i);
 		}
+		sm->commit();
 
 		BOOST_CHECK(sm->root_size() <= sizeof(buffer));
-
 		sm->copy_root(buffer, sizeof(buffer));
 	}
 
 	{
-		auto tm = create_tm();
+		transaction_manager::ptr tm = create_tm();
-		auto sm = persistent_data::open_disk_sm(tm, buffer);
+		persistent_space_map::ptr sm = persistent_data::open_disk_sm(tm, buffer);
+
+		for (unsigned i = 0, step = 1; i < NR_BLOCKS; i += step, step++)
+			BOOST_CHECK_EQUAL(sm->get_count(i), 1);
+	}
+}
+
+//----------------------------------------------------------------
+
+BOOST_AUTO_TEST_CASE(test_metadata_get_nr_blocks)
+{
+	space_map::ptr sm = create_sm_metadata();
+	_test_get_nr_blocks(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_metadata_get_nr_free)
+{
+	space_map::ptr sm = create_sm_metadata();
+	_test_get_nr_free(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_metadata_throws_no_space)
+{
+	space_map::ptr sm = create_sm_metadata();
+	_test_throws_no_space(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_metadata_inc_and_dec)
+{
+	space_map::ptr sm = create_sm_metadata();
+	_test_inc_and_dec(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_metadata_not_allocated_twice)
+{
+	space_map::ptr sm = create_sm_metadata();
+	_test_not_allocated_twice(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_metadata_set_count)
+{
+	space_map::ptr sm = create_sm_metadata();
+	_test_set_count(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_metadata_set_affects_nr_allocated)
+{
+	space_map::ptr sm = create_sm_metadata();
+	_test_set_affects_nr_allocated(sm);
+}
+
+BOOST_AUTO_TEST_CASE(test_metadata_reopen)
+{
+	unsigned char buffer[128];
+
+	{
+		persistent_space_map::ptr sm = create_sm_metadata();
+		for (unsigned i = 0, step = 1; i < NR_BLOCKS; i += step, step++) {
+			sm->inc(i);
+		}
+		sm->commit();
+
+		BOOST_CHECK(sm->root_size() <= sizeof(buffer));
+		sm->copy_root(buffer, sizeof(buffer));
+	}
+
+	{
+		transaction_manager::ptr tm = create_tm();
+		persistent_space_map::ptr sm = persistent_data::open_metadata_sm(tm, buffer);
 
 		for (unsigned i = 0, step = 1; i < NR_BLOCKS; i += step, step++)
 			BOOST_CHECK_EQUAL(sm->get_count(i), 1);