ceph/src/librbd/mirror/DemoteRequest.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 CEPH_LIBRBD_MIRROR_DEMOTE_REQUEST_H
   5 #define CEPH_LIBRBD_MIRROR_DEMOTE_REQUEST_H
   6
   7 #include "cls/rbd/cls_rbd_types.h"
   8 #include "librbd/mirror/Types.h"
   9
  10 struct Context;
  11
  12 namespace librbd {
  13
  14 struct ImageCtx;
  15
  16 namespace mirror {
  17
  18 template <typename ImageCtxT = librbd::ImageCtx>
  19 class DemoteRequest {
  20 public:
  21   static DemoteRequest *create(ImageCtxT &image_ctx, Context *on_finish) {
  22     return new DemoteRequest(image_ctx, on_finish);
  23   }
  24
  25   DemoteRequest(ImageCtxT &image_ctx, Context *on_finish)
  26     : m_image_ctx(image_ctx), m_on_finish(on_finish) {
  27   }
  28
  29   void send();
  30
  31 private:
  32   /**
  33    * @verbatim
  34    *
  35    * <start>
  36    *    |
  37    *    v
  38    * GET_INFO
  39    *    |
  40    *    v
  41    * ACQUIRE_LOCK * * * *
  42    *    |               *
  43    *    v               *
  44    * DEMOTE             *
  45    *    |               *
  46    *    v               *
  47    * RELEASE_LOCK       *
  48    *    |               *
  49    *    v               *
  50    * <finish> < * * * * *
  51    *
  52    * @endverbatim
  53    */
  54
  55   ImageCtxT &m_image_ctx;
  56   Context *m_on_finish;
  57
  58   int m_ret_val = 0;
  59   bool m_blocked_requests = false;
  60
  61   cls::rbd::MirrorImage m_mirror_image;
  62   PromotionState m_promotion_state;
  63
  64   void get_info();
  65   void handle_get_info(int r);
  66
  67   void acquire_lock();
  68   void handle_acquire_lock(int r);
  69
  70   void demote();
  71   void handle_demote(int r);
  72
  73   void release_lock();
  74   void handle_release_lock(int r);
  75
  76   void finish(int r);
  77
  78 };
  79
  80 } // namespace mirror
  81 } // namespace librbd
  82
  83 extern template class librbd::mirror::DemoteRequest<librbd::ImageCtx>;
  84
  85 #endif // CEPH_LIBRBD_MIRROR_DEMOTE_REQUEST_H