1 files changed, 100 insertions, 0 deletions
diff --git a/src/client/barrier.h b/src/client/barrier.h
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+++ b/src/client/barrier.h
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+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ *
+ * Copyright (C) 2012 CohortFS, LLC.
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation.  See file COPYING.
+ *
+ */
+
+#ifndef BARRIER_H
+#define BARRIER_H
+
+#include "include/types.h"
+#include <boost/intrusive/list.hpp>
+#define BOOST_ICL_USE_STATIC_BOUNDED_INTERVALS
+#include <boost/icl/interval_set.hpp>
+#include "common/Mutex.h"
+#include "common/Cond.h"
+
+class Client;
+
+typedef boost::icl::interval<uint64_t>::type barrier_interval;
+
+
+/*
+ * we keep count of uncommitted writes on the inode, so that
+ * ll_commit_blocks can do the right thing.
+ *
+ * This is just a hacked copy of Ceph's sync callback.
+ */
+
+enum CBlockSync_State
+{
+  CBlockSync_State_None, /* initial state */
+  CBlockSync_State_Unclaimed, /* outstanding write */
+  CBlockSync_State_Committing, /* commit in progress */
+  CBlockSync_State_Completed,
+};
+
+class BarrierContext;
+
+class C_Block_Sync;
+
+typedef boost::intrusive::list< C_Block_Sync,
+				boost::intrusive::member_hook<
+				  C_Block_Sync,
+				  boost::intrusive::list_member_hook<>,
+				  &C_Block_Sync::intervals_hook >
+				> BlockSyncList;
+
+class Barrier
+{
+private:
+  Cond cond;
+  boost::icl::interval_set<uint64_t> span;
+  BlockSyncList write_list;
+
+public:
+  boost::intrusive::list_member_hook<> active_commits_hook;
+
+  Barrier();
+  ~Barrier();
+
+  friend class BarrierContext;
+};
+
+typedef boost::intrusive::list< Barrier,
+				boost::intrusive::member_hook<
+				  Barrier,
+				  boost::intrusive::list_member_hook<>,
+				  &Barrier::active_commits_hook >
+				> BarrierList;
+
+class BarrierContext
+{
+private:
+  Client *cl;
+  uint64_t ino;
+  Mutex lock;
+
+  // writes not claimed by a commit
+  BlockSyncList outstanding_writes;
+
+  // commits in progress, with their claimed writes
+  BarrierList active_commits;
+
+public:
+  BarrierContext(Client *c, uint64_t ino);
+  void write_nobarrier(C_Block_Sync &cbs);
+  void write_barrier(C_Block_Sync &cbs);
+  void commit_barrier(barrier_interval &civ);
+  void complete(C_Block_Sync &cbs);
+  ~BarrierContext();
+};
+
+#endif