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diff --git a/include/qemu/transactions.h b/include/qemu/transactions.h
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+++ b/include/qemu/transactions.h
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+/*
+ * Simple transactions API
+ *
+ * Copyright (c) 2021 Virtuozzo International GmbH.
+ *
+ * Author:
+ *  Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ * = Generic transaction API =
+ *
+ * The intended usage is the following: you create "prepare" functions, which
+ * represents the actions. They will usually have Transaction* argument, and
+ * call tran_add() to register finalization callbacks. For finalization
+ * callbacks, prepare corresponding TransactionActionDrv structures.
+ *
+ * Then, when you need to make a transaction, create an empty Transaction by
+ * tran_create(), call your "prepare" functions on it, and finally call
+ * tran_abort() or tran_commit() to finalize the transaction by corresponding
+ * finalization actions in reverse order.
+ */
+
+#ifndef QEMU_TRANSACTIONS_H
+#define QEMU_TRANSACTIONS_H
+
+#include <gmodule.h>
+
+typedef struct TransactionActionDrv {
+    void (*abort)(void *opaque);
+    void (*commit)(void *opaque);
+    void (*clean)(void *opaque);
+} TransactionActionDrv;
+
+typedef struct Transaction Transaction;
+
+Transaction *tran_new(void);
+void tran_add(Transaction *tran, TransactionActionDrv *drv, void *opaque);
+void tran_abort(Transaction *tran);
+void tran_commit(Transaction *tran);
+
+static inline void tran_finalize(Transaction *tran, int ret)
+{
+    if (ret < 0) {
+        tran_abort(tran);
+    } else {
+        tran_commit(tran);
+    }
+}
+
+#endif /* QEMU_TRANSACTIONS_H */