ceph/src/messages/MMDSMap.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
  16 #ifndef CEPH_MMDSMAP_H
  17 #define CEPH_MMDSMAP_H
  18
  19 #include "msg/Message.h"
  20 #include "mds/MDSMap.h"
  21 #include "include/ceph_features.h"
  22
  23 class MMDSMap : public SafeMessage {
  24 private:
  25   static constexpr int HEAD_VERSION = 1;
  26   static constexpr int COMPAT_VERSION = 1;
  27 public:
  28   uuid_d fsid;
  29   epoch_t epoch = 0;
  30   bufferlist encoded;
  31
  32   version_t get_epoch() const { return epoch; }
  33   const bufferlist& get_encoded() const { return encoded; }
  34
  35 protected:
  36   MMDSMap() :
  37     SafeMessage{CEPH_MSG_MDS_MAP, HEAD_VERSION, COMPAT_VERSION} {}
  38   MMDSMap(const uuid_d &f, const MDSMap &mm) :
  39     SafeMessage{CEPH_MSG_MDS_MAP, HEAD_VERSION, COMPAT_VERSION},
  40     fsid(f) {
  41     epoch = mm.get_epoch();
  42     mm.encode(encoded, -1);  // we will reencode with fewer features as necessary
  43   }
  44   ~MMDSMap() override {}
  45
  46 public:
  47   std::string_view get_type_name() const override { return "mdsmap"; }
  48   void print(ostream& out) const override {
  49     out << "mdsmap(e " << epoch << ")";
  50   }
  51
  52   // marshalling
  53   void decode_payload() override {
  54     auto p = payload.cbegin();
  55     decode(fsid, p);
  56     decode(epoch, p);
  57     decode(encoded, p);
  58   }
  59   void encode_payload(uint64_t features) override {
  60     using ceph::encode;
  61     encode(fsid, payload);
  62     encode(epoch, payload);
  63     if ((features & CEPH_FEATURE_PGID64) == 0 ||
  64         (features & CEPH_FEATURE_MDSENC) == 0 ||
  65         (features & CEPH_FEATURE_MSG_ADDR2) == 0 ||
  66         !HAVE_FEATURE(features, SERVER_NAUTILUS)) {
  67       // reencode for old clients.
  68       MDSMap m;
  69       m.decode(encoded);
  70       encoded.clear();
  71       m.encode(encoded, features);
  72     }
  73     encode(encoded, payload);
  74   }
  75 private:
  76   template<class T, typename... Args>
  77   friend boost::intrusive_ptr<T> ceph::make_message(Args&&... args);
  78 };
  79
  80 #endif