ceph/src/mds/MDSTable.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph - scalable distributed file system
   5  *
   6  * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
   7  *
   8  * This is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License version 2.1, as published by the Free Software
  11  * Foundation.  See file COPYING.
  12  *
  13  */
  14
  15 #ifndef CEPH_MDSTABLE_H
  16 #define CEPH_MDSTABLE_H
  17
  18 #include "mdstypes.h"
  19 #include "mds_table_types.h"
  20 #include "include/buffer_fwd.h"
  21
  22 class MDSRank;
  23 class Context;
  24 class MDSInternalContextBase;
  25
  26 class MDSTable {
  27 public:
  28   MDSRank *mds;
  29 protected:
  30   const char *table_name;
  31   bool per_mds;
  32   mds_rank_t rank;
  33
  34   object_t get_object_name() const;
  35
  36   static const int STATE_UNDEF   = 0;
  37   static const int STATE_OPENING = 1;
  38   static const int STATE_ACTIVE  = 2;
  39   //static const int STATE_COMMITTING = 3;
  40   int state;
  41
  42   version_t version, committing_version, committed_version, projected_version;
  43
  44   map<version_t, list<MDSInternalContextBase*> > waitfor_save;
  45
  46 public:
  47   MDSTable(MDSRank *m, const char *n, bool is_per_mds) :
  48     mds(m), table_name(n), per_mds(is_per_mds), rank(MDS_RANK_NONE),
  49     state(STATE_UNDEF),
  50     version(0), committing_version(0), committed_version(0), projected_version(0) {}
  51   virtual ~MDSTable() {}
  52
  53   void set_rank(mds_rank_t r)
  54   {
  55     rank = r;
  56   }
  57
  58   version_t get_version() const { return version; }
  59   version_t get_committed_version() const { return committed_version; }
  60   version_t get_committing_version() const { return committing_version; }
  61   version_t get_projected_version() const { return projected_version; }
  62
  63   void force_replay_version(version_t v) {
  64     version = projected_version = v;
  65   }
  66
  67   //version_t project_version() { return ++projected_version; }
  68   //version_t inc_version() { return ++version; }
  69
  70   // load/save from disk (hack)
  71   bool is_undef() const { return state == STATE_UNDEF; }
  72   bool is_active() const { return state == STATE_ACTIVE; }
  73   bool is_opening() const { return state == STATE_OPENING; }
  74
  75   void reset();
  76   void save(MDSInternalContextBase *onfinish=0, version_t need=0);
  77   void save_2(int r, version_t v);
  78
  79   void shutdown() {
  80     if (is_active()) save(0);
  81   }
  82
  83   void load(MDSInternalContextBase *onfinish);
  84   void load_2(int, bufferlist&, Context *onfinish);
  85
  86   // child must overload these
  87   virtual void reset_state() = 0;
  88   virtual void decode_state(bufferlist::iterator& p) = 0;
  89   virtual void encode_state(bufferlist& bl) const = 0;
  90
  91   friend class C_IO_MT_Load;
  92   friend class C_IO_MT_Save;
  93 };
  94
  95 #endif