ceph/src/mds/MDSTableServer.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_MDSTABLESERVER_H
  16 #define CEPH_MDSTABLESERVER_H
  17
  18 #include "MDSTable.h"
  19 #include "MDSContext.h"
  20
  21 #include "messages/MMDSTableRequest.h"
  22
  23 class MDSTableServer : public MDSTable {
  24 public:
  25   friend class C_ServerRecovery;
  26
  27   MDSTableServer(MDSRank *m, int tab) :
  28     MDSTable(m, get_mdstable_name(tab), false), table(tab) {}
  29   ~MDSTableServer() override {}
  30
  31   virtual void handle_query(const cref_t<MMDSTableRequest> &m) = 0;
  32   virtual void _prepare(const bufferlist &bl, uint64_t reqid, mds_rank_t bymds, bufferlist& out) = 0;
  33   virtual void _get_reply_buffer(version_t tid, bufferlist *pbl) const = 0;
  34   virtual void _commit(version_t tid, cref_t<MMDSTableRequest> req) = 0;
  35   virtual void _rollback(version_t tid) = 0;
  36   virtual void _server_update(bufferlist& bl) { ceph_abort(); }
  37   virtual bool _notify_prep(version_t tid) { return false; };
  38
  39   void _note_prepare(mds_rank_t mds, uint64_t reqid, bool replay=false) {
  40     version++;
  41     if (replay)
  42       projected_version = version;
  43     pending_for_mds[version].mds = mds;
  44     pending_for_mds[version].reqid = reqid;
  45     pending_for_mds[version].tid = version;
  46   }
  47   void _note_commit(uint64_t tid, bool replay=false) {
  48     version++;
  49     if (replay)
  50       projected_version = version;
  51     pending_for_mds.erase(tid);
  52   }
  53   void _note_rollback(uint64_t tid, bool replay=false) {
  54     version++;
  55     if (replay)
  56       projected_version = version;
  57     pending_for_mds.erase(tid);
  58   }
  59   void _note_server_update(bufferlist& bl, bool replay=false) {
  60     version++;
  61     if (replay)
  62       projected_version = version;
  63   }
  64
  65   void reset_state() override {
  66     pending_for_mds.clear();
  67     ++version;
  68   }
  69
  70   void handle_request(const cref_t<MMDSTableRequest> &m);
  71   void do_server_update(bufferlist& bl);
  72
  73   virtual void encode_server_state(bufferlist& bl) const = 0;
  74   virtual void decode_server_state(bufferlist::const_iterator& bl) = 0;
  75
  76   void encode_state(bufferlist& bl) const override {
  77     encode_server_state(bl);
  78     encode(pending_for_mds, bl);
  79   }
  80   void decode_state(bufferlist::const_iterator& bl) override {
  81     decode_server_state(bl);
  82     decode(pending_for_mds, bl);
  83   }
  84
  85   // recovery
  86   void finish_recovery(set<mds_rank_t>& active);
  87   void _do_server_recovery();
  88
  89   void handle_mds_recovery(mds_rank_t who);
  90   void handle_mds_failure_or_stop(mds_rank_t who);
  91 protected:
  92   int table;
  93   bool recovered = false;
  94   set<mds_rank_t> active_clients;
  95 private:
  96   struct notify_info_t {
  97     notify_info_t() {}
  98     set<mds_rank_t> notify_ack_gather;
  99     mds_rank_t mds;
 100     ref_t<MMDSTableRequest> reply = NULL;
 101     MDSContext *onfinish = nullptr;
 102   };
 103
 104   friend class C_Prepare;
 105   friend class C_Commit;
 106   friend class C_Rollback;
 107   friend class C_ServerUpdate;
 108
 109   void handle_prepare(const cref_t<MMDSTableRequest> &m);
 110   void _prepare_logged(const cref_t<MMDSTableRequest> &m, version_t tid);
 111
 112   void handle_commit(const cref_t<MMDSTableRequest> &m);
 113   void _commit_logged(const cref_t<MMDSTableRequest> &m);
 114
 115   void handle_rollback(const cref_t<MMDSTableRequest> &m);
 116   void _rollback_logged(const cref_t<MMDSTableRequest> &m);
 117
 118   void _server_update_logged(bufferlist& bl);
 119
 120   void handle_notify_ack(const cref_t<MMDSTableRequest> &m);
 121
 122   map<version_t,mds_table_pending_t> pending_for_mds;  // ** child should encode this! **
 123   set<version_t> committing_tids;
 124
 125   map<version_t, notify_info_t> pending_notifies;
 126 };
 127 #endif