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 <type_traits>
  13
  14 #define dout_context g_ceph_context
  15 #define dout_subsys ceph_subsys_rbd_mirror
  16 #undef dout_prefix
  17 #define dout_prefix *_dout << "rbd::mirror::image_replayer::" \
  18                            << "PrepareLocalImageRequest: " << this << " " \
  19                            << __func__ << ": "
  20
  21 namespace rbd {
  22 namespace mirror {
  23 namespace image_replayer {
  24
  25 using librbd::util::create_context_callback;
  26 using librbd::util::create_rados_callback;
  27
  28 template <typename I>
  29 void PrepareLocalImageRequest<I>::send() {
  30   dout(20) << dendl;
  31   get_local_image_id();
  32 }
  33
  34 template <typename I>
  35 void PrepareLocalImageRequest<I>::get_local_image_id() {
  36   dout(20) << dendl;
  37
  38   // attempt to cross-reference a local image by the global image id
  39   librados::ObjectReadOperation op;
  40   librbd::cls_client::mirror_image_get_image_id_start(&op, m_global_image_id);
  41
  42   m_out_bl.clear();
  43   librados::AioCompletion *aio_comp = create_rados_callback<
  44     PrepareLocalImageRequest<I>,
  45     &PrepareLocalImageRequest<I>::handle_get_local_image_id>(
  46       this);
  47   int r = m_io_ctx.aio_operate(RBD_MIRRORING, aio_comp, &op, &m_out_bl);
  48   assert(r == 0);
  49   aio_comp->release();
  50 }
  51
  52 template <typename I>
  53 void PrepareLocalImageRequest<I>::handle_get_local_image_id(int r) {
  54   if (r == 0) {
  55     bufferlist::iterator iter = m_out_bl.begin();
  56     r = librbd::cls_client::mirror_image_get_image_id_finish(
  57       &iter, m_local_image_id);
  58   }
  59
  60   dout(20) << "r=" << r << ", "
  61            << "local_image_id=" << *m_local_image_id << dendl;
  62
  63   if (r < 0) {
  64     if (r == -ENOENT) {
  65       dout(10) << "image not registered locally" << dendl;
  66     } else {
  67       derr << "failed to retrieve local image id: " << cpp_strerror(r)
  68            << dendl;
  69     }
  70     finish(r);
  71     return;
  72   }
  73
  74   get_mirror_state();
  75 }
  76
  77 template <typename I>
  78 void PrepareLocalImageRequest<I>::get_mirror_state() {
  79   dout(20) << dendl;
  80
  81   librados::ObjectReadOperation op;
  82   librbd::cls_client::mirror_image_get_start(&op, *m_local_image_id);
  83
  84   m_out_bl.clear();
  85   librados::AioCompletion *aio_comp = create_rados_callback<
  86     PrepareLocalImageRequest<I>,
  87     &PrepareLocalImageRequest<I>::handle_get_mirror_state>(this);
  88   int r = m_io_ctx.aio_operate(RBD_MIRRORING, aio_comp, &op, &m_out_bl);
  89   assert(r == 0);
  90   aio_comp->release();
  91 }
  92
  93 template <typename I>
  94 void PrepareLocalImageRequest<I>::handle_get_mirror_state(int r) {
  95   dout(20) << ": r=" << r << dendl;
  96
  97   cls::rbd::MirrorImage mirror_image;
  98   if (r == 0) {
  99     bufferlist::iterator iter = m_out_bl.begin();
 100     r = librbd::cls_client::mirror_image_get_finish(&iter, &mirror_image);
 101   }
 102
 103   if (r < 0) {
 104     derr << "failed to retrieve image mirror state: " << cpp_strerror(r)
 105          << dendl;
 106     finish(r);
 107     return;
 108   }
 109
 110   // TODO save current mirror state to determine if we should
 111   // delete a partially formed image
 112   // (e.g. MIRROR_IMAGE_STATE_CREATING/DELETING)
 113
 114   get_tag_owner();
 115 }
 116
 117 template <typename I>
 118 void PrepareLocalImageRequest<I>::get_tag_owner() {
 119   // deduce the class type for the journal to support unit tests
 120   using Journal = typename std::decay<
 121     typename std::remove_pointer<decltype(std::declval<I>().journal)>
 122     ::type>::type;
 123
 124   dout(20) << dendl;
 125
 126   Context *ctx = create_context_callback<
 127     PrepareLocalImageRequest<I>,
 128     &PrepareLocalImageRequest<I>::handle_get_tag_owner>(this);
 129   Journal::get_tag_owner(m_io_ctx, *m_local_image_id, m_tag_owner,
 130                          m_work_queue, ctx);
 131 }
 132
 133 template <typename I>
 134 void PrepareLocalImageRequest<I>::handle_get_tag_owner(int r) {
 135   dout(20) << "r=" << r << ", "
 136            << "tag_owner=" << *m_tag_owner << dendl;
 137
 138   if (r < 0) {
 139     derr << "failed to retrieve journal tag owner: " << cpp_strerror(r)
 140          << dendl;
 141     finish(r);
 142     return;
 143   }
 144
 145   finish(0);
 146 }
 147
 148 template <typename I>
 149 void PrepareLocalImageRequest<I>::finish(int r) {
 150   dout(20) << "r=" << r << dendl;
 151
 152   m_on_finish->complete(r);
 153   delete this;
 154 }
 155
 156 } // namespace image_replayer
 157 } // namespace mirror
 158 } // namespace rbd
 159
 160 template class rbd::mirror::image_replayer::PrepareLocalImageRequest<librbd::ImageCtx>;