ceph/src/librbd/image/SetSnapRequest.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_IMAGE_SNAP_SET_REQUEST_H
   5 #define CEPH_LIBRBD_IMAGE_SNAP_SET_REQUEST_H
   6
   7 #include "cls/rbd/cls_rbd_client.h"
   8 #include <string>
   9
  10 class Context;
  11
  12 namespace librbd {
  13
  14 template <typename> class ExclusiveLock;
  15 class ImageCtx;
  16 template <typename> class ObjectMap;
  17
  18 namespace image {
  19
  20 template <typename> class RefreshParentRequest;
  21
  22 template <typename ImageCtxT = ImageCtx>
  23 class SetSnapRequest {
  24 public:
  25   static SetSnapRequest *create(ImageCtxT &image_ctx,
  26                                 const cls::rbd::SnapshotNamespace& snap_namespace,
  27                                 const std::string &snap_name,
  28                                 Context *on_finish) {
  29     return new SetSnapRequest(image_ctx, snap_namespace, snap_name, on_finish);
  30   }
  31
  32   ~SetSnapRequest();
  33
  34   void send();
  35
  36 private:
  37   /**
  38    * @verbatim
  39    *
  40    * <start>
  41    *    |
  42    *    | (set snap)
  43    *    |-----------> BLOCK_WRITES
  44    *    |                 |
  45    *    |                 v
  46    *    |             SHUTDOWN_EXCLUSIVE_LOCK (skip if lock inactive
  47    *    |                 |                    or disabled)
  48    *    |                 v
  49    *    |             REFRESH_PARENT (skip if no parent
  50    *    |                 |           or refresh not needed)
  51    *    |                 v
  52    *    |             OPEN_OBJECT_MAP (skip if map disabled)
  53    *    |                 |
  54    *    |                 v
  55    *    |              <apply>
  56    *    |                 |
  57    *    |                 v
  58    *    |             FINALIZE_REFRESH_PARENT (skip if no parent
  59    *    |                 |                    or refresh not needed)
  60    *    |                 v
  61    *    |             <finish>
  62    *    |
  63    *    \-----------> INIT_EXCLUSIVE_LOCK (skip if active or
  64    *                      |                disabled)
  65    *                      v
  66    *                  REFRESH_PARENT (skip if no parent
  67    *                      |           or refresh not needed)
  68    *                      v
  69    *                   <apply>
  70    *                      |
  71    *                      v
  72    *                  FINALIZE_REFRESH_PARENT (skip if no parent
  73    *                      |                    or refresh not needed)
  74    *                      v
  75    *                  <finish>
  76    *
  77    * @endverbatim
  78    */
  79
  80   SetSnapRequest(ImageCtxT &image_ctx, const cls::rbd::SnapshotNamespace& snap_namespace,
  81                  const std::string &snap_name,
  82                 Context *on_finish);
  83
  84   ImageCtxT &m_image_ctx;
  85   cls::rbd::SnapshotNamespace m_snap_namespace;
  86   std::string m_snap_name;
  87   Context *m_on_finish;
  88
  89   uint64_t m_snap_id;
  90   ExclusiveLock<ImageCtxT> *m_exclusive_lock;
  91   ObjectMap<ImageCtxT> *m_object_map;
  92   RefreshParentRequest<ImageCtxT> *m_refresh_parent;
  93
  94   bool m_writes_blocked;
  95
  96   void send_block_writes();
  97   Context *handle_block_writes(int *result);
  98
  99   void send_init_exclusive_lock();
 100   Context *handle_init_exclusive_lock(int *result);
 101
 102   Context *send_shut_down_exclusive_lock(int *result);
 103   Context *handle_shut_down_exclusive_lock(int *result);
 104
 105   Context *send_refresh_parent(int *result);
 106   Context *handle_refresh_parent(int *result);
 107
 108   Context *send_open_object_map(int *result);
 109   Context *handle_open_object_map(int *result);
 110
 111   Context *send_finalize_refresh_parent(int *result);
 112   Context *handle_finalize_refresh_parent(int *result);
 113
 114   int apply();
 115   void finalize();
 116   void send_complete();
 117 };
 118
 119 } // namespace image
 120 } // namespace librbd
 121
 122 extern template class librbd::image::SetSnapRequest<librbd::ImageCtx>;
 123
 124 #endif // CEPH_LIBRBD_IMAGE_SNAP_SET_REQUEST_H