Blob support for IDB [Chromium]

content/browser/indexed_db/indexed_db_backing_store.cc

Index: content/browser/indexed_db/indexed_db_backing_store.cc
diff --git a/content/browser/indexed_db/indexed_db_backing_store.cc b/content/browser/indexed_db/indexed_db_backing_store.cc
index 36e514ad2afef6fd7054cb7c13a3887dfad06ce9..8988aed645d01c2d3b95611dcf3fda24df7c37f3 100644
--- a/content/browser/indexed_db/indexed_db_backing_store.cc
+++ b/content/browser/indexed_db/indexed_db_backing_store.cc
@@ -128,6 +128,8 @@ enum IndexedDBBackingStoreErrorSource {
   CLEAR_OBJECT_STORE,
   READ_BLOB_JOURNAL,
   DECODE_BLOB_JOURNAL,
+  GET_BLOB_KEY_GENERATOR_CURRENT_NUMBER,
+  GET_BLOB_INFO_FOR_RECORD,
   INTERNAL_ERROR_MAX,
 };
 
@@ -304,7 +306,8 @@ const char* IndexedDBBackingStore::Comparator::Name() const {
 // 0 - Initial version.
 // 1 - Adds UserIntVersion to DatabaseMetaData.
 // 2 - Adds DataVersion to to global metadata.
-static const int64 kLatestKnownSchemaVersion = 2;
+// 3 - Adds metadata needed for blob support.
+static const int64 kLatestKnownSchemaVersion = 3;
 WARN_UNUSED_RESULT static bool IsSchemaKnown(LevelDBDatabase* db, bool* known) {
   int64 db_schema_version = 0;
   bool found = false;
@@ -341,15 +344,16 @@ WARN_UNUSED_RESULT static bool IsSchemaKnown(LevelDBDatabase* db, bool* known) {
   return true;
 }
 
-WARN_UNUSED_RESULT static bool SetUpMetadata(
-    LevelDBDatabase* db,
-    const std::string& origin_identifier) {
+// TODO(ericu): Move this down into the member section of this file.  I'm
+// leaving it here for this CL as it's easier to see the diffs in place.
+WARN_UNUSED_RESULT bool IndexedDBBackingStore::SetUpMetadata() {
   const uint32 latest_known_data_version =
       blink::kSerializedScriptValueVersion;
   const std::string schema_version_key = SchemaVersionKey::Encode();
   const std::string data_version_key = DataVersionKey::Encode();
 
-  scoped_refptr<LevelDBTransaction> transaction = new LevelDBTransaction(db);
+  scoped_refptr<LevelDBTransaction> transaction =
+      new LevelDBTransaction(db_.get());
 
   int64 db_schema_version = 0;
   int64 db_data_version = 0;
@@ -366,6 +370,12 @@ WARN_UNUSED_RESULT static bool SetUpMetadata(
     PutInt(transaction.get(), schema_version_key, db_schema_version);
     db_data_version = latest_known_data_version;
     PutInt(transaction.get(), data_version_key, db_data_version);
+    // If a blob directory already exists for this database, blow it away.  It's
+    // leftover from a partially-purged previous generation of data.
+    if (!base::DeleteFile(blob_path_, true)) {
+      INTERNAL_WRITE_ERROR_UNTESTED(SET_UP_METADATA);
+      return false;
+    }
   } else {
     // Upgrade old backing store.
     DCHECK_LE(db_schema_version, kLatestKnownSchemaVersion);
@@ -373,10 +383,10 @@ WARN_UNUSED_RESULT static bool SetUpMetadata(
       db_schema_version = 1;
       PutInt(transaction.get(), schema_version_key, db_schema_version);
       const std::string start_key =
-          DatabaseNameKey::EncodeMinKeyForOrigin(origin_identifier);
+          DatabaseNameKey::EncodeMinKeyForOrigin(origin_identifier_);
       const std::string stop_key =
-          DatabaseNameKey::EncodeStopKeyForOrigin(origin_identifier);
-      scoped_ptr<LevelDBIterator> it = db->CreateIterator();
+          DatabaseNameKey::EncodeStopKeyForOrigin(origin_identifier_);
+      scoped_ptr<LevelDBIterator> it = db_->CreateIterator();
       for (s = it->Seek(start_key);
            s.ok() && it->IsValid() && CompareKeys(it->Key(), stop_key) < 0;
            s = it->Next()) {
@@ -404,6 +414,13 @@ WARN_UNUSED_RESULT static bool SetUpMetadata(
       db_data_version = blink::kSerializedScriptValueVersion;
       PutInt(transaction.get(), data_version_key, db_data_version);
     }
+    if (db_schema_version < 3) {
+      db_schema_version = 3;
+      if (!base::DeleteFile(blob_path_, true)) {
+        INTERNAL_WRITE_ERROR_UNTESTED(SET_UP_METADATA);
+        return false;
+      }
+    }
   }
 
   if (!s.ok()) {
@@ -480,6 +497,55 @@ class DefaultLevelDBFactory : public LevelDBFactory {
   }
 };
 
+static bool GetBlobKeyGeneratorCurrentNumber(
+    LevelDBTransaction* leveldb_transaction,
+    int64 database_id,
+    int64* blob_key_generator_current_number) {
+  const std::string key_gen_key = DatabaseMetaDataKey::Encode(
+      database_id, DatabaseMetaDataKey::BLOB_KEY_GENERATOR_CURRENT_NUMBER);
+
+  // Default to initial number if not found.
+  int64 cur_number = DatabaseMetaDataKey::kBlobKeyGeneratorInitialNumber;
+  std::string data;
+
+  bool found = false;
+  bool ok = leveldb_transaction->Get(key_gen_key, &data, &found).ok();
+  if (!ok) {
+    INTERNAL_READ_ERROR_UNTESTED(GET_BLOB_KEY_GENERATOR_CURRENT_NUMBER);
+    return false;
+  }
+  if (found) {
+    StringPiece slice(data);
+    if (!DecodeVarInt(&slice, &cur_number) || !slice.empty() ||
+        !DatabaseMetaDataKey::IsValidBlobKey(cur_number)) {
+      INTERNAL_READ_ERROR_UNTESTED(GET_BLOB_KEY_GENERATOR_CURRENT_NUMBER);
+      return false;
+    }
+  }
+  *blob_key_generator_current_number = cur_number;
+  return true;
+}
+
+static bool UpdateBlobKeyGeneratorCurrentNumber(
+    LevelDBTransaction* leveldb_transaction,
+    int64 database_id,
+    int64 blob_key_generator_current_number) {
+#ifndef NDEBUG
+  int64 old_number;
+  if (!GetBlobKeyGeneratorCurrentNumber(
+          leveldb_transaction, database_id, &old_number))
+    return false;
+  DCHECK_LT(old_number, blob_key_generator_current_number);
+#endif
+  DCHECK(
+      DatabaseMetaDataKey::IsValidBlobKey(blob_key_generator_current_number));
+  const std::string key = DatabaseMetaDataKey::Encode(
+      database_id, DatabaseMetaDataKey::BLOB_KEY_GENERATOR_CURRENT_NUMBER);
+
+  PutVarInt(leveldb_transaction, key, blob_key_generator_current_number);
+  return true;
+}
+
 // TODO(ericu): Error recovery. If we persistently can't read the
 // blob journal, the safe thing to do is to clear it and leak the blobs,
 // though that may be costly. Still, database/directory deletion should always
@@ -573,6 +639,64 @@ static leveldb::Status MergeDatabaseIntoLiveBlobJournal(
   return leveldb::Status::OK();
 }
 
+// Blob Data is encoded as a series of:
+//   { is_file [bool], key [int64 as varInt],
+//     type [string-with-length, may be empty],
+//     (for Blobs only) size [int64 as varInt]
+//     (for Files only) fileName [string-with-length]
+//   }
+// There is no length field; just read until you run out of data.
+static std::string EncodeBlobData(
+    const std::vector<IndexedDBBlobInfo*>& blob_info) {
+  std::string ret;
+  std::vector<IndexedDBBlobInfo*>::const_iterator iter;
+  for (iter = blob_info.begin(); iter != blob_info.end(); ++iter) {
+    const IndexedDBBlobInfo& info = **iter;
+    EncodeBool(info.is_file(), &ret);
+    EncodeVarInt(info.key(), &ret);
+    EncodeStringWithLength(info.type(), &ret);
+    if (info.is_file())
+      EncodeStringWithLength(info.file_name(), &ret);
+    else
+      EncodeVarInt(info.size(), &ret);
+  }
+  return ret;
+}
+
+static bool DecodeBlobData(const std::string& data,
+                           std::vector<IndexedDBBlobInfo>* output) {
+  std::vector<IndexedDBBlobInfo> ret;
+  output->clear();
+  StringPiece slice(data);
+  while (!slice.empty()) {
+    bool is_file;
+    int64 key;
+    base::string16 type;
+    int64 size;
+    base::string16 file_name;
+
+    if (!DecodeBool(&slice, &is_file))
+      return false;
+    if (!DecodeVarInt(&slice, &key) ||
+        !DatabaseMetaDataKey::IsValidBlobKey(key))
+      return false;
+    if (!DecodeStringWithLength(&slice, &type))
+      return false;
+    if (is_file) {
+      if (!DecodeStringWithLength(&slice, &file_name))
+        return false;
+      ret.push_back(IndexedDBBlobInfo(key, type, file_name));
+    } else {
+      if (!DecodeVarInt(&slice, &size) || size < 0)
+        return false;
+      ret.push_back(IndexedDBBlobInfo(type, static_cast<uint64>(size), key));
+    }
+  }
+  output->swap(ret);
+
+  return true;
+}
+
 IndexedDBBackingStore::IndexedDBBackingStore(
     IndexedDBFactory* indexed_db_factory,
     const GURL& origin_url,
@@ -589,7 +713,8 @@ IndexedDBBackingStore::IndexedDBBackingStore(
       task_runner_(task_runner),
       db_(db.Pass()),
       comparator_(comparator.Pass()),
-      active_blob_registry_(this) {}
+      active_blob_registry_(this) {
+}
 
 IndexedDBBackingStore::~IndexedDBBackingStore() {
   if (!blob_path_.empty() && !child_process_ids_granted_.empty()) {
@@ -638,6 +763,7 @@ enum IndexedDBBackingStoreOpenResult {
   INDEXED_DB_BACKING_STORE_OPEN_ORIGIN_TOO_LONG,
   INDEXED_DB_BACKING_STORE_OPEN_NO_RECOVERY,
   INDEXED_DB_BACKING_STORE_OPEN_FAILED_PRIOR_CORRUPTION,
+  INDEXED_DB_BACKING_STORE_OPEN_FAILED_CLEANUP_JOURNAL_ERROR,
   INDEXED_DB_BACKING_STORE_OPEN_MAX,
 };
 
@@ -923,13 +1049,22 @@ scoped_refptr<IndexedDBBackingStore> IndexedDBBackingStore::Open(
     return scoped_refptr<IndexedDBBackingStore>();
   }
 
-  return Create(indexed_db_factory,
-                origin_url,
-                blob_path,
-                request_context,
-                db.Pass(),
-                comparator.Pass(),
-                task_runner);
+  scoped_refptr<IndexedDBBackingStore> backing_store =
+      Create(indexed_db_factory,
+             origin_url,
+             blob_path,
+             request_context,
+             db.Pass(),
+             comparator.Pass(),
+             task_runner);
+
+  if (clean_journal && backing_store &&
+      !backing_store->CleanUpBlobJournal(LiveBlobJournalKey::Encode()).ok()) {
+    HistogramOpenStatus(
+        INDEXED_DB_BACKING_STORE_OPEN_FAILED_CLEANUP_JOURNAL_ERROR, origin_url);
+    return scoped_refptr<IndexedDBBackingStore>();
+  }
+  return backing_store;
 }
 
 // static
@@ -986,8 +1121,7 @@ scoped_refptr<IndexedDBBackingStore> IndexedDBBackingStore::Create(
                                 db.Pass(),
                                 comparator.Pass(),
                                 task_runner));
-  if (!SetUpMetadata(backing_store->db_.get(),
-                     backing_store->origin_identifier_))
+  if (!backing_store->SetUpMetadata())
     return scoped_refptr<IndexedDBBackingStore>();
 
   return backing_store;
@@ -1084,6 +1218,29 @@ leveldb::Status IndexedDBBackingStore::GetIDBDatabaseMetaData(
     INTERNAL_READ_ERROR_UNTESTED(GET_IDBDATABASE_METADATA);
   }
 
+  // We don't cache this, we just check it if it's there.
+  int64 blob_key_generator_current_number =
+      DatabaseMetaDataKey::kInvalidBlobKey;
+
+  s = GetVarInt(
+      db_.get(),
+      DatabaseMetaDataKey::Encode(
+          metadata->id, DatabaseMetaDataKey::BLOB_KEY_GENERATOR_CURRENT_NUMBER),
+      &blob_key_generator_current_number,
+      found);
+  if (!s.ok()) {
+    INTERNAL_READ_ERROR_UNTESTED(GET_IDBDATABASE_METADATA);
+    return s;
+  }
+  if (!*found) {
+    // This database predates blob support.
+    *found = true;
+  } else if (!DatabaseMetaDataKey::IsValidBlobKey(
+                 blob_key_generator_current_number)) {
+    INTERNAL_CONSISTENCY_ERROR_UNTESTED(GET_IDBDATABASE_METADATA);
+    return InternalInconsistencyStatus();
+  }
+
   return s;
 }
 
@@ -1137,6 +1294,12 @@ leveldb::Status IndexedDBBackingStore::CreateIDBDatabaseMetaData(
             DatabaseMetaDataKey::Encode(*row_id,
                                         DatabaseMetaDataKey::USER_INT_VERSION),
             int_version);
+  PutVarInt(
+      transaction.get(),
+      DatabaseMetaDataKey::Encode(
+          *row_id, DatabaseMetaDataKey::BLOB_KEY_GENERATOR_CURRENT_NUMBER),
+      DatabaseMetaDataKey::kBlobKeyGeneratorInitialNumber);
+
   s = transaction->Commit();
   if (!s.ok())
     INTERNAL_WRITE_ERROR_UNTESTED(CREATE_IDBDATABASE_METADATA);
@@ -1157,27 +1320,84 @@ bool IndexedDBBackingStore::UpdateIDBDatabaseIntVersion(
   return true;
 }
 
-static leveldb::Status DeleteRange(LevelDBTransaction* transaction,
-                                   const std::string& begin,
-                                   const std::string& end) {
+// Note that if you're deleting a range that contains user keys that have blob
+// info, this won't clean up the blobs.
+static leveldb::Status DeleteRangeByKeys(LevelDBTransaction* transaction,
+                                         const std::string& begin,
+                                         const std::string& end,
+                                         bool upper_open) {
   scoped_ptr<LevelDBIterator> it = transaction->CreateIterator();
   leveldb::Status s;
   for (s = it->Seek(begin);
-       s.ok() && it->IsValid() && CompareKeys(it->Key(), end) < 0;
+       s.ok() && it->IsValid() &&
+           (upper_open ?
+               CompareKeys(it->Key(), end) < 0 :
+               CompareKeys(it->Key(), end) <= 0);
        s = it->Next())
     transaction->Remove(it->Key());
   return s;
 }
 
+static leveldb::Status DeleteBlobsInRange(
+    IndexedDBBackingStore::Transaction* transaction,
+    int64 database_id,
+    int64 object_store_id,
+    const std::string& start_key,
+    const std::string& end_key,
+    bool upper_open) {
+
+  scoped_ptr<LevelDBIterator> it = transaction->transaction()->CreateIterator();
+  leveldb::Status s = it->Seek(start_key);
+  for (; s.ok() && it->IsValid() &&
+       (upper_open ?
+          CompareKeys(it->Key(), end_key) < 0 :
+          CompareKeys(it->Key(), end_key) <= 0);
+       s = it->Next()) {
+    StringPiece key_piece(it->Key());
+    std::string user_key =
+        BlobEntryKey::ReencodeToObjectStoreDataKey(&key_piece);
+    if (!user_key.size()) {
+      INTERNAL_CONSISTENCY_ERROR_UNTESTED(GET_IDBDATABASE_METADATA);
+      return InternalInconsistencyStatus();
+    }
+    transaction->PutBlobInfo(
+        database_id, object_store_id, user_key, NULL, NULL);
+  }
+  return s;
+}
+
+// For a whole-object-store deletion, we still use the one-blob-record-at-a-time
+// deletion mechanism designed for normal transactions. We could go with the
+// nuke-the-whole-directory method used for deleteDatabase if we structured the
+// directories accordingly, but that would complicate the kind of info we store
+// in the LevelDBTransaction and lengthen paths.
+static leveldb::Status DeleteBlobsInObjectStore(
+    IndexedDBBackingStore::Transaction* transaction,
+    int64 database_id,
+    int64 object_store_id) {
+  std::string start_key, end_key;
+  start_key =
+      BlobEntryKey::EncodeMinKeyForObjectStore(database_id, object_store_id);
+  end_key =
+      BlobEntryKey::EncodeStopKeyForObjectStore(database_id, object_store_id);
+  return DeleteBlobsInRange(transaction, database_id, object_store_id,
+      start_key, end_key, true);
+}
+
 leveldb::Status IndexedDBBackingStore::DeleteDatabase(
     const base::string16& name) {
   IDB_TRACE("IndexedDBBackingStore::DeleteDatabase");
   scoped_ptr<LevelDBDirectTransaction> transaction =
       LevelDBDirectTransaction::Create(db_.get());
 
+  leveldb::Status s;
+  s = CleanUpBlobJournal(BlobJournalKey::Encode());
+  if (!s.ok())
+    return s;
+
   IndexedDBDatabaseMetadata metadata;
   bool success = false;
-  leveldb::Status s = GetIDBDatabaseMetaData(name, &metadata, &success);
+  s = GetIDBDatabaseMetaData(name, &metadata, &success);
   if (!s.ok())
     return s;
   if (!success)
@@ -1200,16 +1420,15 @@ leveldb::Status IndexedDBBackingStore::DeleteDatabase(
   const std::string key = DatabaseNameKey::Encode(origin_identifier_, name);
   transaction->Remove(key);
 
-  // TODO(ericu): Put the real calls to the blob journal code here.  For now,
-  // I've inserted fake calls so that we don't get "you didn't use this static
-  // function" compiler errors.
-  if (false) {
-    scoped_refptr<LevelDBTransaction> fake_transaction =
-        new LevelDBTransaction(NULL);
-    BlobJournalType fake_journal;
-    MergeDatabaseIntoLiveBlobJournal(transaction.get(), metadata.id);
+  bool need_cleanup = false;
+  if (active_blob_registry()->MarkDeletedCheckIfUsed(
+          metadata.id, DatabaseMetaDataKey::kAllBlobsKey)) {
+    s = MergeDatabaseIntoLiveBlobJournal(transaction.get(), metadata.id);
+    if (!s.ok())
+      return s;
+  } else {
     UpdateBlobJournalWithDatabase(transaction.get(), metadata.id);
-    MergeBlobsIntoLiveBlobJournal(fake_transaction.get(), fake_journal);
+    need_cleanup = true;
   }
 
   s = transaction->Commit();
@@ -1217,6 +1436,10 @@ leveldb::Status IndexedDBBackingStore::DeleteDatabase(
     INTERNAL_WRITE_ERROR_UNTESTED(DELETE_DATABASE);
     return s;
   }
+
+  if (need_cleanup)
+    CleanUpBlobJournal(BlobJournalKey::Encode());
+
   db_->Compact(start_key, stop_key);
   return s;
 }
@@ -1230,13 +1453,14 @@ static bool CheckObjectStoreAndMetaDataType(const LevelDBIterator* it,
 
   StringPiece slice(it->Key());
   ObjectStoreMetaDataKey meta_data_key;
-  bool ok = ObjectStoreMetaDataKey::Decode(&slice, &meta_data_key);
+  bool ok =
+      ObjectStoreMetaDataKey::Decode(&slice, &meta_data_key) && slice.empty();
   DCHECK(ok);
   if (meta_data_key.ObjectStoreId() != object_store_id)
     return false;
   if (meta_data_key.MetaDataType() != meta_data_type)
     return false;
-  return true;
+  return ok;
 }
 
 // TODO(jsbell): This should do some error handling rather than
@@ -1525,26 +1749,35 @@ leveldb::Status IndexedDBBackingStore::DeleteObjectStore(
     return InternalInconsistencyStatus();
   }
 
-  s = DeleteRange(
+  s = DeleteBlobsInObjectStore(transaction, database_id, object_store_id);
+  if (!s.ok()) {
+    INTERNAL_CONSISTENCY_ERROR_UNTESTED(DELETE_OBJECT_STORE);
+    return s;
+  }
+
+  s = DeleteRangeByKeys(
       leveldb_transaction,
       ObjectStoreMetaDataKey::Encode(database_id, object_store_id, 0),
-      ObjectStoreMetaDataKey::EncodeMaxKey(database_id, object_store_id));
+      ObjectStoreMetaDataKey::EncodeMaxKey(database_id, object_store_id),
+      true);
 
   if (s.ok()) {
     leveldb_transaction->Remove(
         ObjectStoreNamesKey::Encode(database_id, object_store_name));
 
-    s = DeleteRange(
+    s = DeleteRangeByKeys(
         leveldb_transaction,
         IndexFreeListKey::Encode(database_id, object_store_id, 0),
-        IndexFreeListKey::EncodeMaxKey(database_id, object_store_id));
+        IndexFreeListKey::EncodeMaxKey(database_id, object_store_id),
+        true);
   }
 
   if (s.ok()) {
-    s = DeleteRange(
+    s = DeleteRangeByKeys(
         leveldb_transaction,
         IndexMetaDataKey::Encode(database_id, object_store_id, 0, 0),
-        IndexMetaDataKey::EncodeMaxKey(database_id, object_store_id));
+        IndexMetaDataKey::EncodeMaxKey(database_id, object_store_id),
+        true);
   }
 
   if (!s.ok()) {
@@ -1593,7 +1826,7 @@ leveldb::Status IndexedDBBackingStore::GetRecord(
   }
 
   record->bits = slice.as_string();
-  return s;
+  return transaction->GetBlobInfoForRecord(database_id, leveldb_key, record);
 }
 
 WARN_UNUSED_RESULT static leveldb::Status GetNewVersionNumber(
@@ -1687,11 +1920,13 @@ leveldb::Status IndexedDBBackingStore::ClearObjectStore(
   const std::string stop_key =
       KeyPrefix(database_id, object_store_id + 1).Encode();
 
-  leveldb::Status s =
-      DeleteRange(transaction->transaction(), start_key, stop_key);
-  if (!s.ok())
+  leveldb::Status s = DeleteRangeByKeys(
+      transaction->transaction(), start_key, stop_key, true);
+  if (!s.ok()) {
     INTERNAL_WRITE_ERROR(CLEAR_OBJECT_STORE);
-  return s;
+    return s;
+  }
+  return DeleteBlobsInObjectStore(transaction, database_id, object_store_id);
 }
 
 leveldb::Status IndexedDBBackingStore::DeleteRecord(
@@ -1716,6 +1951,68 @@ leveldb::Status IndexedDBBackingStore::DeleteRecord(
   return leveldb::Status::OK();
 }
 
+// TODO(ericu): Exists entries as well?  Anything to do index-wise?
+leveldb::Status IndexedDBBackingStore::DeleteRange(
+    IndexedDBBackingStore::Transaction* transaction,
+    int64 database_id,
+    int64 object_store_id,
+    const IndexedDBKeyRange& key_range) {
+  leveldb::Status s;
+  scoped_ptr<IndexedDBBackingStore::Cursor> start_cursor =
+      OpenObjectStoreCursor(transaction,
+                            database_id,
+                            object_store_id,
+                            key_range,
+                            indexed_db::CURSOR_NEXT,
+                            &s);
+  if (!s.ok())
+    return s;
+  if (!start_cursor)
+    return leveldb::Status::OK(); // Empty range == delete success.
+
+  scoped_ptr<IndexedDBBackingStore::Cursor> end_cursor =
+      OpenObjectStoreCursor(transaction,
+                            database_id,
+                            object_store_id,
+                            key_range,
+                            indexed_db::CURSOR_PREV,
+                            &s);
+
+  if (!s.ok())
+    return s;
+  if (!end_cursor)
+    return leveldb::Status::OK(); // Empty range == delete success.
+  // TODO(ericu): Is that right?  Or perhaps only in single-key ranges, in which
+  // case we should give an error here and check differently above?
+
+  BlobEntryKey start_blob_key, end_blob_key;
+
+  std::string start_key = ObjectStoreDataKey::Encode(
+          database_id, object_store_id, start_cursor->key());
+  base::StringPiece start_key_piece(start_key);
+  if (!BlobEntryKey::FromObjectStoreDataKey(&start_key_piece, &start_blob_key))
+    return InternalInconsistencyStatus();
+  std::string end_key = ObjectStoreDataKey::Encode(
+          database_id, object_store_id, end_cursor->key());
+  base::StringPiece end_key_piece(end_key);
+  if (!BlobEntryKey::FromObjectStoreDataKey(&end_key_piece, &end_blob_key))
+    return InternalInconsistencyStatus();
+
+  s = DeleteBlobsInRange(transaction, database_id, object_store_id,
+      start_blob_key.Encode(), end_blob_key.Encode(), false);
+  if (!s.ok())
+    return s;
+  s = DeleteRangeByKeys(transaction->transaction(), start_key, end_key, false);
+  if (!s.ok())
+    return s;
+  start_key = ExistsEntryKey::Encode(
+          database_id, object_store_id, start_cursor->key());
+  end_key = ExistsEntryKey::Encode(
+          database_id, object_store_id, end_cursor->key());
+  return DeleteRangeByKeys(
+      transaction->transaction(), start_key, end_key, false);
+}
+
 leveldb::Status IndexedDBBackingStore::GetKeyGeneratorCurrentNumber(
     IndexedDBBackingStore::Transaction* transaction,
     int64 database_id,
@@ -2290,6 +2587,70 @@ leveldb::Status IndexedDBBackingStore::CleanUpBlobJournal(
   return journal_transaction->Commit();
 }
 
+leveldb::Status IndexedDBBackingStore::Transaction::GetBlobInfoForRecord(
+    int64 database_id,
+    const std::string& object_store_data_key,
+    IndexedDBValue* value) {
+  BlobChangeRecord* change_record = NULL;
+  BlobChangeMap::const_iterator blob_iter =
+      blob_change_map_.find(object_store_data_key);
+  if (blob_iter != blob_change_map_.end()) {
+    change_record = blob_iter->second;
+  } else {
+    blob_iter = incognito_blob_map_.find(object_store_data_key);
+    if (blob_iter != incognito_blob_map_.end())
+      change_record = blob_iter->second;
+  }
+  if (change_record) {
+    // Either we haven't written the blob to disk yet or we're in incognito
+    // mode, so we have to send back the one they sent us.  This change record
+    // includes the original UUID.
+    value->blob_info = change_record->blob_info();
+    return leveldb::Status::OK();
+  }
+
+  BlobEntryKey blob_entry_key;
+  StringPiece leveldb_key_piece(object_store_data_key);
+  if (!BlobEntryKey::FromObjectStoreDataKey(&leveldb_key_piece,
+                                            &blob_entry_key)) {
+    NOTREACHED();
+    return InternalInconsistencyStatus();
+  }
+  scoped_ptr<LevelDBIterator> it = transaction()->CreateIterator();
+  std::string encoded_key = blob_entry_key.Encode();
+  leveldb::Status s = it->Seek(encoded_key);
+  if (!s.ok())
+    return s;
+  if (it->IsValid() && CompareKeys(it->Key(), encoded_key) == 0) {
+    if (!DecodeBlobData(it->Value().as_string(), &value->blob_info)) {
+      INTERNAL_READ_ERROR(GET_BLOB_INFO_FOR_RECORD);
+      return InternalInconsistencyStatus();
+    }
+    std::vector<IndexedDBBlobInfo>::iterator iter;
+    for (iter = value->blob_info.begin(); iter != value->blob_info.end();
+         ++iter) {
+      iter->set_file_path(
+          backing_store_->GetBlobFileName(database_id, iter->key()));
+      iter->set_mark_used_callback(
+          backing_store_->active_blob_registry()->GetAddBlobRefCallback(
+              database_id, iter->key()));
+      iter->set_release_callback(
+          backing_store_->active_blob_registry()->GetFinalReleaseCallback(
+              database_id, iter->key()));
+      if (iter->is_file()) {
+        base::File::Info info;
+        if (base::GetFileInfo(iter->file_path(), &info)) {
+          // This should always work, but it isn't fatal if it doesn't; it just
+          // means a potential slow synchronous call from the renderer later.
+          iter->set_last_modified(info.last_modified);
+          iter->set_size(info.size);
+        }
+      }
+    }
+  }
+  return leveldb::Status::OK();
+}
+
 void IndexedDBBackingStore::CleanPrimaryJournalIgnoreReturn() {
   CleanUpBlobJournal(BlobJournalKey::Encode());
 }
@@ -2370,15 +2731,16 @@ leveldb::Status IndexedDBBackingStore::DeleteIndex(
       IndexMetaDataKey::Encode(database_id, object_store_id, index_id, 0);
   const std::string index_meta_data_end =
       IndexMetaDataKey::EncodeMaxKey(database_id, object_store_id, index_id);
-  leveldb::Status s = DeleteRange(
-      leveldb_transaction, index_meta_data_start, index_meta_data_end);
+  leveldb::Status s = DeleteRangeByKeys(
+      leveldb_transaction, index_meta_data_start, index_meta_data_end, true);
 
   if (s.ok()) {
     const std::string index_data_start =
         IndexDataKey::EncodeMinKey(database_id, object_store_id, index_id);
     const std::string index_data_end =
         IndexDataKey::EncodeMaxKey(database_id, object_store_id, index_id);
-    s = DeleteRange(leveldb_transaction, index_data_start, index_data_end);
+    s = DeleteRangeByKeys(
+        leveldb_transaction, index_data_start, index_data_end, true);
   }
 
   if (!s.ok())
@@ -2613,11 +2975,13 @@ leveldb::Status IndexedDBBackingStore::KeyExistsInIndex(
 
 IndexedDBBackingStore::Cursor::Cursor(
     const IndexedDBBackingStore::Cursor* other)
-    : transaction_(other->transaction_),
+    : backing_store_(other->backing_store_),
+      transaction_(other->transaction_),
+      database_id_(other->database_id_),
       cursor_options_(other->cursor_options_),
       current_key_(new IndexedDBKey(*other->current_key_)) {
   if (other->iterator_) {
-    iterator_ = transaction_->CreateIterator();
+    iterator_ = transaction_->transaction()->CreateIterator();
 
     if (other->iterator_->IsValid()) {
       leveldb::Status s = iterator_->Seek(other->iterator_->Key());
@@ -2627,13 +2991,20 @@ IndexedDBBackingStore::Cursor::Cursor(
   }
 }
 
-IndexedDBBackingStore::Cursor::Cursor(LevelDBTransaction* transaction,
-                                      const CursorOptions& cursor_options)
-    : transaction_(transaction), cursor_options_(cursor_options) {}
+IndexedDBBackingStore::Cursor::Cursor(
+    scoped_refptr<IndexedDBBackingStore> backing_store,
+    IndexedDBBackingStore::Transaction* transaction,
+    int64 database_id,
+    const CursorOptions& cursor_options)
+    : backing_store_(backing_store),
+      transaction_(transaction),
+      database_id_(database_id),
+      cursor_options_(cursor_options) {
+}
 IndexedDBBackingStore::Cursor::~Cursor() {}
 
 bool IndexedDBBackingStore::Cursor::FirstSeek(leveldb::Status* s) {
-  iterator_ = transaction_->CreateIterator();
+  iterator_ = transaction_->transaction()->CreateIterator();
   if (cursor_options_.forward)
     *s = iterator_->Seek(cursor_options_.low_key);
   else
@@ -2816,9 +3187,14 @@ IndexedDBBackingStore::Cursor::record_identifier() const {
 class ObjectStoreKeyCursorImpl : public IndexedDBBackingStore::Cursor {
  public:
   ObjectStoreKeyCursorImpl(
-      LevelDBTransaction* transaction,
+      scoped_refptr<IndexedDBBackingStore> backing_store,
+      IndexedDBBackingStore::Transaction* transaction,
+      int64 database_id,
       const IndexedDBBackingStore::Cursor::CursorOptions& cursor_options)
-      : IndexedDBBackingStore::Cursor(transaction, cursor_options) {}
+      : IndexedDBBackingStore::Cursor(backing_store,
+                                      transaction,
+                                      database_id,
+                                      cursor_options) {}
 
   virtual Cursor* Clone() OVERRIDE {
     return new ObjectStoreKeyCursorImpl(this);
@@ -2875,9 +3251,14 @@ bool ObjectStoreKeyCursorImpl::LoadCurrentRow() {
 class ObjectStoreCursorImpl : public IndexedDBBackingStore::Cursor {
  public:
   ObjectStoreCursorImpl(
-      LevelDBTransaction* transaction,
+      scoped_refptr<IndexedDBBackingStore> backing_store,
+      IndexedDBBackingStore::Transaction* transaction,
+      int64 database_id,
       const IndexedDBBackingStore::Cursor::CursorOptions& cursor_options)
-      : IndexedDBBackingStore::Cursor(transaction, cursor_options) {}
+      : IndexedDBBackingStore::Cursor(backing_store,
+                                      transaction,
+                                      database_id,
+                                      cursor_options) {}
 
   virtual Cursor* Clone() OVERRIDE { return new ObjectStoreCursorImpl(this); }
 
@@ -2926,6 +3307,11 @@ bool ObjectStoreCursorImpl::LoadCurrentRow() {
   EncodeIDBKey(*current_key_, &encoded_key);
   record_identifier_.Reset(encoded_key, version);
 
+  if (!transaction_->GetBlobInfoForRecord(database_id_,
+                                          iterator_->Key().as_string(),
+                                          &current_value_).ok()) {
+    return false;
+  }
   current_value_.bits = value_slice.as_string();
   return true;
 }
@@ -2933,9 +3319,14 @@ bool ObjectStoreCursorImpl::LoadCurrentRow() {
 class IndexKeyCursorImpl : public IndexedDBBackingStore::Cursor {
  public:
   IndexKeyCursorImpl(
-      LevelDBTransaction* transaction,
+      scoped_refptr<IndexedDBBackingStore> backing_store,
+      IndexedDBBackingStore::Transaction* transaction,
+      int64 database_id,
       const IndexedDBBackingStore::Cursor::CursorOptions& cursor_options)
-      : IndexedDBBackingStore::Cursor(transaction, cursor_options) {}
+      : IndexedDBBackingStore::Cursor(backing_store,
+                                      transaction,
+                                      database_id,
+                                      cursor_options) {}
 
   virtual Cursor* Clone() OVERRIDE { return new IndexKeyCursorImpl(this); }
 
@@ -3008,13 +3399,14 @@ bool IndexKeyCursorImpl::LoadCurrentRow() {
 
   std::string result;
   bool found = false;
-  leveldb::Status s = transaction_->Get(primary_leveldb_key, &result, &found);
+  leveldb::Status s =
+      transaction_->transaction()->Get(primary_leveldb_key, &result, &found);
   if (!s.ok()) {
     INTERNAL_READ_ERROR_UNTESTED(LOAD_CURRENT_ROW);
     return false;
   }
   if (!found) {
-    transaction_->Remove(iterator_->Key());
+    transaction_->transaction()->Remove(iterator_->Key());
     return false;
   }
   if (!result.size()) {
@@ -3030,7 +3422,7 @@ bool IndexKeyCursorImpl::LoadCurrentRow() {
   }
 
   if (object_store_data_version != index_data_version) {
-    transaction_->Remove(iterator_->Key());
+    transaction_->transaction()->Remove(iterator_->Key());
     return false;
   }
 
@@ -3040,9 +3432,14 @@ bool IndexKeyCursorImpl::LoadCurrentRow() {
 class IndexCursorImpl : public IndexedDBBackingStore::Cursor {
  public:
   IndexCursorImpl(
-      LevelDBTransaction* transaction,
+      scoped_refptr<IndexedDBBackingStore> backing_store,
+      IndexedDBBackingStore::Transaction* transaction,
+      int64 database_id,
       const IndexedDBBackingStore::Cursor::CursorOptions& cursor_options)
-      : IndexedDBBackingStore::Cursor(transaction, cursor_options) {}
+      : IndexedDBBackingStore::Cursor(backing_store,
+                                      transaction,
+                                      database_id,
+                                      cursor_options) {}
 
   virtual Cursor* Clone() OVERRIDE { return new IndexCursorImpl(this); }
 
@@ -3108,6 +3505,7 @@ bool IndexCursorImpl::LoadCurrentRow() {
     return false;
   }
 
+  DCHECK_EQ(index_data_key.DatabaseId(), database_id_);
   primary_leveldb_key_ =
       ObjectStoreDataKey::Encode(index_data_key.DatabaseId(),
                                  index_data_key.ObjectStoreId(),
@@ -3115,13 +3513,14 @@ bool IndexCursorImpl::LoadCurrentRow() {
 
   std::string result;
   bool found = false;
-  leveldb::Status s = transaction_->Get(primary_leveldb_key_, &result, &found);
+  leveldb::Status s =
+      transaction_->transaction()->Get(primary_leveldb_key_, &result, &found);
   if (!s.ok()) {
     INTERNAL_READ_ERROR_UNTESTED(LOAD_CURRENT_ROW);
     return false;
   }
   if (!found) {
-    transaction_->Remove(iterator_->Key());
+    transaction_->transaction()->Remove(iterator_->Key());
     return false;
   }
   if (!result.size()) {
@@ -3137,12 +3536,14 @@ bool IndexCursorImpl::LoadCurrentRow() {
   }
 
   if (object_store_data_version != index_data_version) {
-    transaction_->Remove(iterator_->Key());
+    transaction_->transaction()->Remove(iterator_->Key());
     return false;
   }
 
   current_value_.bits = slice.as_string();
-  return true;
+  return transaction_->GetBlobInfoForRecord(database_id_,
+                                            primary_leveldb_key_,
+                                            &current_value_).ok();
 }
 
 bool ObjectStoreCursorOptions(
@@ -3309,8 +3710,8 @@ IndexedDBBackingStore::OpenObjectStoreCursor(
                                 direction,
                                 &cursor_options))
     return scoped_ptr<IndexedDBBackingStore::Cursor>();
-  scoped_ptr<ObjectStoreCursorImpl> cursor(
-      new ObjectStoreCursorImpl(leveldb_transaction, cursor_options));
+  scoped_ptr<ObjectStoreCursorImpl> cursor(new ObjectStoreCursorImpl(
+      this, transaction, database_id, cursor_options));
   if (!cursor->FirstSeek(s))
     return scoped_ptr<IndexedDBBackingStore::Cursor>();
 
@@ -3336,8 +3737,8 @@ IndexedDBBackingStore::OpenObjectStoreKeyCursor(
                                 direction,
                                 &cursor_options))
     return scoped_ptr<IndexedDBBackingStore::Cursor>();
-  scoped_ptr<ObjectStoreKeyCursorImpl> cursor(
-      new ObjectStoreKeyCursorImpl(leveldb_transaction, cursor_options));
+  scoped_ptr<ObjectStoreKeyCursorImpl> cursor(new ObjectStoreKeyCursorImpl(
+      this, transaction, database_id, cursor_options));
   if (!cursor->FirstSeek(s))
     return scoped_ptr<IndexedDBBackingStore::Cursor>();
 
@@ -3366,7 +3767,7 @@ IndexedDBBackingStore::OpenIndexKeyCursor(
                           &cursor_options))
     return scoped_ptr<IndexedDBBackingStore::Cursor>();
   scoped_ptr<IndexKeyCursorImpl> cursor(
-      new IndexKeyCursorImpl(leveldb_transaction, cursor_options));
+      new IndexKeyCursorImpl(this, transaction, database_id, cursor_options));
   if (!cursor->FirstSeek(s))
     return scoped_ptr<IndexedDBBackingStore::Cursor>();
 
@@ -3394,7 +3795,7 @@ IndexedDBBackingStore::OpenIndexCursor(
                           &cursor_options))
     return scoped_ptr<IndexedDBBackingStore::Cursor>();
   scoped_ptr<IndexCursorImpl> cursor(
-      new IndexCursorImpl(leveldb_transaction, cursor_options));
+      new IndexCursorImpl(this, transaction, database_id, cursor_options));
   if (!cursor->FirstSeek(s))
     return scoped_ptr<IndexedDBBackingStore::Cursor>();
 
@@ -3427,10 +3828,194 @@ void IndexedDBBackingStore::Transaction::Begin() {
     incognito_blob_map_[iter->first] = iter->second->Clone().release();
 }
 
-leveldb::Status IndexedDBBackingStore::Transaction::Commit() {
-  IDB_TRACE("IndexedDBBackingStore::Transaction::Commit");
-  DCHECK(transaction_.get());
-  leveldb::Status s = transaction_->Commit();
+static GURL getURLFromUUID(const string& uuid) {
+  return GURL("blob:uuid/" + uuid);
+}
+
+leveldb::Status IndexedDBBackingStore::Transaction::HandleBlobPreTransaction(
+    BlobEntryKeyValuePairVec* new_blob_entries,
+    WriteDescriptorVec* new_files_to_write) {
+  if (backing_store_->is_incognito())
+    return leveldb::Status::OK();
+
+  BlobChangeMap::iterator iter = blob_change_map_.begin();
+  new_blob_entries->clear();
+  new_files_to_write->clear();
+  if (iter != blob_change_map_.end()) {
+    // Create LevelDBTransaction for the name generator seed and add-journal.
+    scoped_refptr<LevelDBTransaction> pre_transaction =
+        new LevelDBTransaction(backing_store_->db_.get());
+    BlobJournalType journal;
+    for (; iter != blob_change_map_.end(); ++iter) {
+      std::vector<IndexedDBBlobInfo>::iterator info_iter;
+      std::vector<IndexedDBBlobInfo*> new_blob_keys;
+      for (info_iter = iter->second->mutable_blob_info().begin();
+           info_iter != iter->second->mutable_blob_info().end();
+           ++info_iter) {
+        int64 next_blob_key = -1;
+        bool result = GetBlobKeyGeneratorCurrentNumber(
+            pre_transaction.get(), database_id_, &next_blob_key);
+        if (!result || next_blob_key < 0)
+          return InternalInconsistencyStatus();
+        BlobJournalEntryType journal_entry =
+            std::make_pair(database_id_, next_blob_key);
+        journal.push_back(journal_entry);
+        if (info_iter->is_file()) {
+          new_files_to_write->push_back(
+              WriteDescriptor(info_iter->file_path(), next_blob_key));
+        } else {
+          new_files_to_write->push_back(WriteDescriptor(
+              getURLFromUUID(info_iter->uuid()), next_blob_key));
+        }
+        info_iter->set_key(next_blob_key);
+        new_blob_keys.push_back(&*info_iter);
+        result = UpdateBlobKeyGeneratorCurrentNumber(
+            pre_transaction.get(), database_id_, next_blob_key + 1);
+        if (!result)
+          return InternalInconsistencyStatus();
+      }
+      BlobEntryKey blob_entry_key;
+      StringPiece key_piece(iter->second->key());
+      if (!BlobEntryKey::FromObjectStoreDataKey(&key_piece, &blob_entry_key)) {
+        NOTREACHED();
+        return InternalInconsistencyStatus();
+      }
+      new_blob_entries->push_back(
+          std::make_pair(blob_entry_key, EncodeBlobData(new_blob_keys)));
+    }
+    UpdatePrimaryJournalWithBlobList(pre_transaction.get(), journal);
+    if (!pre_transaction->Commit().ok())
+      return InternalInconsistencyStatus();
+  }
+  return leveldb::Status::OK();
+}
+
+bool IndexedDBBackingStore::Transaction::CollectBlobFilesToRemove() {
+  if (backing_store_->is_incognito())
+    return true;
+
+  BlobChangeMap::const_iterator iter = blob_change_map_.begin();
+  // Look up all old files to remove as part of the transaction, store their
+  // names in blobs_to_remove_, and remove their old blob data entries.
+  if (iter != blob_change_map_.end()) {
+    scoped_ptr<LevelDBIterator> db_iter = transaction_->CreateIterator();
+    for (; iter != blob_change_map_.end(); ++iter) {
+      BlobEntryKey blob_entry_key;
+      StringPiece key_piece(iter->second->key());
+      if (!BlobEntryKey::FromObjectStoreDataKey(&key_piece, &blob_entry_key)) {
+        NOTREACHED();
+        INTERNAL_WRITE_ERROR(TRANSACTION_COMMIT_METHOD);
+        transaction_ = NULL;
+        return false;
+      }
+      if (database_id_ < 0)
+        database_id_ = blob_entry_key.database_id();
+      else
+        DCHECK_EQ(database_id_, blob_entry_key.database_id());
+      std::string blob_entry_key_bytes = blob_entry_key.Encode();
+      db_iter->Seek(blob_entry_key_bytes);
+      if (db_iter->IsValid() &&
+          !CompareKeys(db_iter->Key(), blob_entry_key_bytes)) {
+        std::vector<IndexedDBBlobInfo> blob_info;
+        if (!DecodeBlobData(db_iter->Value().as_string(), &blob_info)) {
+          INTERNAL_READ_ERROR(TRANSACTION_COMMIT_METHOD);
+          transaction_ = NULL;
+          return false;
+        }
+        std::vector<IndexedDBBlobInfo>::iterator blob_info_iter;
+        for (blob_info_iter = blob_info.begin();
+             blob_info_iter != blob_info.end();
+             ++blob_info_iter)
+          blobs_to_remove_.push_back(
+              std::make_pair(database_id_, blob_info_iter->key()));
+        transaction_->Remove(blob_entry_key_bytes);
+      }
+    }
+  }
+  return true;
+}
+
+leveldb::Status IndexedDBBackingStore::Transaction::SortBlobsToRemove() {
+  IndexedDBActiveBlobRegistry* registry =
+      backing_store_->active_blob_registry();
+  BlobJournalType::iterator iter;
+  BlobJournalType primary_journal, live_blob_journal;
+  for (iter = blobs_to_remove_.begin(); iter != blobs_to_remove_.end();
+       ++iter) {
+    if (registry->MarkDeletedCheckIfUsed(iter->first, iter->second))
+      live_blob_journal.push_back(*iter);
+    else
+      primary_journal.push_back(*iter);
+  }
+  UpdatePrimaryJournalWithBlobList(transaction_.get(), primary_journal);
+  leveldb::Status s =
+      MergeBlobsIntoLiveBlobJournal(transaction_.get(), live_blob_journal);
+  if (!s.ok())
+    return s;
+  // To signal how many blobs need attention right now.
+  blobs_to_remove_.swap(primary_journal);
+  return leveldb::Status::OK();
+}
+
+leveldb::Status IndexedDBBackingStore::Transaction::CommitPhaseOne(
+    scoped_refptr<BlobWriteCallback> callback) {
+  IDB_TRACE("IndexedDBBackingStore::Transaction::CommitPhaseOne");
+  DCHECK(transaction_);
+  DCHECK(backing_store_->task_runner()->RunsTasksOnCurrentThread());
+
+  leveldb::Status s;
+
+  s = backing_store_->CleanUpBlobJournal(BlobJournalKey::Encode());
+  if (!s.ok()) {
+    INTERNAL_WRITE_ERROR(TRANSACTION_COMMIT_METHOD);
+    transaction_ = NULL;
+    return s;
+  }
+
+  BlobEntryKeyValuePairVec new_blob_entries;
+  WriteDescriptorVec new_files_to_write;
+  s = HandleBlobPreTransaction(&new_blob_entries, &new_files_to_write);
+  if (!s.ok()) {
+    INTERNAL_WRITE_ERROR(TRANSACTION_COMMIT_METHOD);
+    transaction_ = NULL;
+    return s;
+  }
+
+  DCHECK(!new_files_to_write.size() ||
+         KeyPrefix::IsValidDatabaseId(database_id_));
+  if (!CollectBlobFilesToRemove()) {
+    INTERNAL_WRITE_ERROR(TRANSACTION_COMMIT_METHOD);
+    transaction_ = NULL;
+    return InternalInconsistencyStatus();
+  }
+
+  if (new_files_to_write.size()) {
+    // This kicks off the writes of the new blobs, if any.
+    // This call will zero out new_blob_entries and new_files_to_write.
+    WriteNewBlobs(new_blob_entries, new_files_to_write, callback);
+    // Remove the add journal, if any; once the blobs are written, and we
+    // commit, this will do the cleanup.
+    ClearBlobJournal(transaction_.get(), BlobJournalKey::Encode());
+  } else {
+    callback->Run(true);
+  }
+
+  return leveldb::Status::OK();
+}
+
+leveldb::Status IndexedDBBackingStore::Transaction::CommitPhaseTwo() {
+  IDB_TRACE("IndexedDBBackingStore::Transaction::CommitPhaseTwo");
+  leveldb::Status s;
+  if (blobs_to_remove_.size()) {
+    s = SortBlobsToRemove();
+    if (!s.ok()) {
+      INTERNAL_WRITE_ERROR(TRANSACTION_COMMIT_METHOD);
+      transaction_ = NULL;
+      return s;
+    }
+  }
+
+  s = transaction_->Commit();
   transaction_ = NULL;
 
   if (s.ok() && backing_store_->is_incognito() && !blob_change_map_.empty()) {
@@ -3451,6 +4036,9 @@ leveldb::Status IndexedDBBackingStore::Transaction::Commit() {
   }
   if (!s.ok())
     INTERNAL_WRITE_ERROR_UNTESTED(TRANSACTION_COMMIT_METHOD);
+  else if (blobs_to_remove_.size())
+    s = backing_store_->CleanUpBlobJournal(BlobJournalKey::Encode());
+
   return s;
 }