ceph/src/tools/rbd_mirror/image_replayer/PrepareLocalImageRequest.cc

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3
   4 #include "tools/rbd_mirror/image_replayer/PrepareLocalImageRequest.h"
   5 #include "include/rados/librados.hpp"
   6 #include "cls/rbd/cls_rbd_client.h"
   7 #include "common/errno.h"
   8 #include "librbd/ImageCtx.h"
   9 #include "librbd/Journal.h"
  10 #include "librbd/Utils.h"
  11 #include "tools/rbd_mirror/Threads.h"
  12 #include "tools/rbd_mirror/image_replayer/GetMirrorImageIdRequest.h"
  13 #include <type_traits>
  14
  15 #define dout_context g_ceph_context
  16 #define dout_subsys ceph_subsys_rbd_mirror
  17 #undef dout_prefix
  18 #define dout_prefix *_dout << "rbd::mirror::image_replayer::" \
  19                            << "PrepareLocalImageRequest: " << this << " " \
  20                            << __func__ << ": "
  21
  22 namespace rbd {
  23 namespace mirror {
  24 namespace image_replayer {
  25
  26 using librbd::util::create_context_callback;
  27 using librbd::util::create_rados_callback;
  28
  29 template <typename I>
  30 void PrepareLocalImageRequest<I>::send() {
  31   dout(20) << dendl;
  32   get_local_image_id();
  33 }
  34
  35 template <typename I>
  36 void PrepareLocalImageRequest<I>::get_local_image_id() {
  37   dout(20) << dendl;
  38
  39   Context *ctx = create_context_callback<
  40     PrepareLocalImageRequest<I>,
  41     &PrepareLocalImageRequest<I>::handle_get_local_image_id>(this);
  42   auto req = GetMirrorImageIdRequest<I>::create(m_io_ctx, m_global_image_id,
  43                                                 m_local_image_id, ctx);
  44   req->send();
  45 }
  46
  47 template <typename I>
  48 void PrepareLocalImageRequest<I>::handle_get_local_image_id(int r) {
  49   dout(20) << "r=" << r << ", "
  50            << "local_image_id=" << *m_local_image_id << dendl;
  51
  52   if (r < 0) {
  53     finish(r);
  54     return;
  55   }
  56
  57   get_local_image_name();
  58 }
  59
  60 template <typename I>
  61 void PrepareLocalImageRequest<I>::get_local_image_name() {
  62   dout(20) << dendl;
  63
  64   librados::ObjectReadOperation op;
  65   librbd::cls_client::dir_get_name_start(&op, *m_local_image_id);
  66
  67   m_out_bl.clear();
  68   librados::AioCompletion *aio_comp = create_rados_callback<
  69     PrepareLocalImageRequest<I>,
  70     &PrepareLocalImageRequest<I>::handle_get_local_image_name>(this);
  71   int r = m_io_ctx.aio_operate(RBD_DIRECTORY, aio_comp, &op, &m_out_bl);
  72   assert(r == 0);
  73   aio_comp->release();
  74 }
  75
  76 template <typename I>
  77 void PrepareLocalImageRequest<I>::handle_get_local_image_name(int r) {
  78   dout(20) << "r=" << r << dendl;
  79
  80   if (r == 0) {
  81     bufferlist::iterator it = m_out_bl.begin();
  82     r = librbd::cls_client::dir_get_name_finish(&it, m_local_image_name);
  83   }
  84
  85   if (r < 0) {
  86     if (r != -ENOENT) {
  87       derr << "failed to retrieve image name: " << cpp_strerror(r) << dendl;
  88     }
  89     finish(r);
  90     return;
  91   }
  92
  93   get_mirror_state();
  94 }
  95
  96 template <typename I>
  97 void PrepareLocalImageRequest<I>::get_mirror_state() {
  98   dout(20) << dendl;
  99
 100   librados::ObjectReadOperation op;
 101   librbd::cls_client::mirror_image_get_start(&op, *m_local_image_id);
 102
 103   m_out_bl.clear();
 104   librados::AioCompletion *aio_comp = create_rados_callback<
 105     PrepareLocalImageRequest<I>,
 106     &PrepareLocalImageRequest<I>::handle_get_mirror_state>(this);
 107   int r = m_io_ctx.aio_operate(RBD_MIRRORING, aio_comp, &op, &m_out_bl);
 108   assert(r == 0);
 109   aio_comp->release();
 110 }
 111
 112 template <typename I>
 113 void PrepareLocalImageRequest<I>::handle_get_mirror_state(int r) {
 114   dout(20) << ": r=" << r << dendl;
 115
 116   cls::rbd::MirrorImage mirror_image;
 117   if (r == 0) {
 118     bufferlist::iterator iter = m_out_bl.begin();
 119     r = librbd::cls_client::mirror_image_get_finish(&iter, &mirror_image);
 120   }
 121
 122   if (r < 0) {
 123     derr << "failed to retrieve image mirror state: " << cpp_strerror(r)
 124          << dendl;
 125     finish(r);
 126     return;
 127   }
 128
 129   // TODO save current mirror state to determine if we should
 130   // delete a partially formed image
 131   // (e.g. MIRROR_IMAGE_STATE_CREATING/DELETING)
 132
 133   get_tag_owner();
 134 }
 135
 136 template <typename I>
 137 void PrepareLocalImageRequest<I>::get_tag_owner() {
 138   // deduce the class type for the journal to support unit tests
 139   using Journal = typename std::decay<
 140     typename std::remove_pointer<decltype(std::declval<I>().journal)>
 141     ::type>::type;
 142
 143   dout(20) << dendl;
 144
 145   Context *ctx = create_context_callback<
 146     PrepareLocalImageRequest<I>,
 147     &PrepareLocalImageRequest<I>::handle_get_tag_owner>(this);
 148   Journal::get_tag_owner(m_io_ctx, *m_local_image_id, m_tag_owner,
 149                          m_work_queue, ctx);
 150 }
 151
 152 template <typename I>
 153 void PrepareLocalImageRequest<I>::handle_get_tag_owner(int r) {
 154   dout(20) << "r=" << r << ", "
 155            << "tag_owner=" << *m_tag_owner << dendl;
 156
 157   if (r < 0) {
 158     derr << "failed to retrieve journal tag owner: " << cpp_strerror(r)
 159          << dendl;
 160     finish(r);
 161     return;
 162   }
 163
 164   finish(0);
 165 }
 166
 167 template <typename I>
 168 void PrepareLocalImageRequest<I>::finish(int r) {
 169   dout(20) << "r=" << r << dendl;
 170
 171   m_on_finish->complete(r);
 172   delete this;
 173 }
 174
 175 } // namespace image_replayer
 176 } // namespace mirror
 177 } // namespace rbd
 178
 179 template class rbd::mirror::image_replayer::PrepareLocalImageRequest<librbd::ImageCtx>;