ceph/src/tools/rbd_mirror/image_replayer/EventPreprocessor.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3
   4 #ifndef RBD_MIRROR_IMAGE_REPLAYER_EVENT_PREPROCESSOR_H
   5 #define RBD_MIRROR_IMAGE_REPLAYER_EVENT_PREPROCESSOR_H
   6
   7 #include "include/int_types.h"
   8 #include "librbd/journal/Types.h"
   9 #include "librbd/journal/TypeTraits.h"
  10 #include <map>
  11 #include <string>
  12 #include <boost/variant/static_visitor.hpp>
  13
  14 struct Context;
  15 struct ContextWQ;
  16 namespace journal { class Journaler; }
  17 namespace librbd { class ImageCtx; }
  18
  19 namespace rbd {
  20 namespace mirror {
  21 namespace image_replayer {
  22
  23 template <typename ImageCtxT = librbd::ImageCtx>
  24 class EventPreprocessor {
  25 public:
  26   using Journaler = typename librbd::journal::TypeTraits<ImageCtxT>::Journaler;
  27   using EventEntry = librbd::journal::EventEntry;
  28   using MirrorPeerClientMeta = librbd::journal::MirrorPeerClientMeta;
  29
  30   static EventPreprocessor *create(ImageCtxT &local_image_ctx,
  31                                    Journaler &remote_journaler,
  32                                    const std::string &local_mirror_uuid,
  33                                    MirrorPeerClientMeta *client_meta,
  34                                    ContextWQ *work_queue) {
  35     return new EventPreprocessor(local_image_ctx, remote_journaler,
  36                                  local_mirror_uuid, client_meta, work_queue);
  37   }
  38
  39   static void destroy(EventPreprocessor* processor) {
  40     delete processor;
  41   }
  42
  43   EventPreprocessor(ImageCtxT &local_image_ctx, Journaler &remote_journaler,
  44                     const std::string &local_mirror_uuid,
  45                     MirrorPeerClientMeta *client_meta, ContextWQ *work_queue);
  46   ~EventPreprocessor();
  47
  48   bool is_required(const EventEntry &event_entry);
  49   void preprocess(EventEntry *event_entry, Context *on_finish);
  50
  51 private:
  52   /**
  53    * @verbatim
  54    *
  55    * <start>
  56    *    |
  57    *    v (skip if not required)
  58    * REFRESH_IMAGE
  59    *    |
  60    *    v (skip if not required)
  61    * PREPROCESS_EVENT
  62    *    |
  63    *    v (skip if not required)
  64    * UPDATE_CLIENT
  65    *
  66    * @endverbatim
  67    */
  68
  69   typedef std::map<uint64_t, uint64_t> SnapSeqs;
  70
  71   class PreprocessEventVisitor : public boost::static_visitor<int> {
  72   public:
  73     EventPreprocessor *event_preprocessor;
  74
  75     PreprocessEventVisitor(EventPreprocessor *event_preprocessor)
  76       : event_preprocessor(event_preprocessor) {
  77     }
  78
  79     template <typename T>
  80     inline int operator()(T&) const {
  81       return 0;
  82     }
  83     inline int operator()(librbd::journal::SnapRenameEvent &event) const {
  84       return event_preprocessor->preprocess_snap_rename(event);
  85     }
  86   };
  87
  88   ImageCtxT &m_local_image_ctx;
  89   Journaler &m_remote_journaler;
  90   std::string m_local_mirror_uuid;
  91   MirrorPeerClientMeta *m_client_meta;
  92   ContextWQ *m_work_queue;
  93
  94   bool m_in_progress = false;
  95   EventEntry *m_event_entry = nullptr;
  96   Context *m_on_finish = nullptr;
  97
  98   SnapSeqs m_snap_seqs;
  99   bool m_snap_seqs_updated = false;
 100
 101   bool prune_snap_map(SnapSeqs *snap_seqs);
 102
 103   void refresh_image();
 104   void handle_refresh_image(int r);
 105
 106   void preprocess_event();
 107   int preprocess_snap_rename(librbd::journal::SnapRenameEvent &event);
 108
 109   void update_client();
 110   void handle_update_client(int r);
 111
 112   void finish(int r);
 113
 114 };
 115
 116 } // namespace image_replayer
 117 } // namespace mirror
 118 } // namespace rbd
 119
 120 extern template class rbd::mirror::image_replayer::EventPreprocessor<librbd::ImageCtx>;
 121
 122 #endif // RBD_MIRROR_IMAGE_REPLAYER_EVENT_PREPROCESSOR_H