rbd-mirror: load/update image map state machine

Signed-off-by: Venky Shankar <vshankar@redhat.com>

src/tools/rbd_mirror/CMakeLists.txt

@@ -19,6 +19,8 @@ set(rbd_mirror_internal
   ServiceDaemon.cc
   Threads.cc
   types.cc
+  image_map/LoadRequest.cc
+  image_map/UpdateRequest.cc
   image_replayer/BootstrapRequest.cc
   image_replayer/CloseImageRequest.cc
   image_replayer/CreateImageRequest.cc
@@ -38,6 +40,7 @@ set(rbd_mirror_internal
   image_sync/SyncPointPruneRequest.cc
   pool_watcher/RefreshImagesRequest.cc
   service_daemon/Types.cc)
+
 add_library(rbd_mirror_internal STATIC
   ${rbd_mirror_internal})
 

src/tools/rbd_mirror/image_map/LoadRequest.cc

@@ -0,0 +1,98 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "common/debug.h"
+#include "common/errno.h"
+
+#include "librbd/Utils.h"
+#include "include/rbd_types.h"
+#include "cls/rbd/cls_rbd_client.h"
+
+#include "LoadRequest.h"
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_rbd_mirror
+#undef dout_prefix
+#define dout_prefix *_dout << "rbd::mirror::image_map::LoadRequest: "   \
+                           << this << " " << __func__
+
+namespace rbd {
+namespace mirror {
+namespace image_map {
+
+static const uint32_t MAX_RETURN = 1024;
+
+using librbd::util::create_rados_callback;
+
+template<typename I>
+LoadRequest<I>::LoadRequest(librados::IoCtx &ioctx,
+                            std::map<std::string, cls::rbd::MirrorImageMap> *image_mapping,
+                            Context *on_finish)
+  : m_ioctx(ioctx),
+    m_image_mapping(image_mapping),
+    m_on_finish(on_finish) {
+}
+
+template<typename I>
+void LoadRequest<I>::send() {
+  dout(20) << dendl;
+
+  image_map_list();
+}
+
+template<typename I>
+void LoadRequest<I>::image_map_list() {
+  dout(20) << dendl;
+
+  librados::ObjectReadOperation op;
+  librbd::cls_client::mirror_image_map_list_start(&op, m_start_after, MAX_RETURN);
+
+  librados::AioCompletion *aio_comp = create_rados_callback<
+    LoadRequest, &LoadRequest::handle_image_map_list>(this);
+
+  m_out_bl.clear();
+  int r = m_ioctx.aio_operate(RBD_MIRROR_LEADER, aio_comp, &op, &m_out_bl);
+  assert(r == 0);
+  aio_comp->release();
+}
+
+template<typename I>
+void LoadRequest<I>::handle_image_map_list(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  std::map<std::string, cls::rbd::MirrorImageMap> image_mapping;
+  if (r == 0) {
+    bufferlist::iterator it = m_out_bl.begin();
+    r = librbd::cls_client::mirror_image_map_list_finish(&it, &image_mapping);
+  }
+
+  if (r < 0) {
+    derr << ": failed to get image map: " << cpp_strerror(r) << dendl;
+    finish(r);
+    return;
+  }
+
+  m_image_mapping->insert(image_mapping.begin(), image_mapping.end());
+
+  if (image_mapping.size() == MAX_RETURN) {
+    m_start_after = image_mapping.rbegin()->first;
+    image_map_list();
+    return;
+  }
+
+  finish(0);
+}
+
+template<typename I>
+void LoadRequest<I>::finish(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  m_on_finish->complete(r);
+  delete this;
+}
+
+} // namespace image_map
+} // namespace mirror
+} // namespace rbd
+
+template class rbd::mirror::image_map::LoadRequest<librbd::ImageCtx>;

src/tools/rbd_mirror/image_map/LoadRequest.h

@@ -0,0 +1,64 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#ifndef CEPH_RBD_MIRROR_IMAGE_MAP_LOAD_REQUEST_H
+#define CEPH_RBD_MIRROR_IMAGE_MAP_LOAD_REQUEST_H
+
+#include "cls/rbd/cls_rbd_types.h"
+#include "include/rados/librados.hpp"
+
+class Context;
+
+namespace librbd { class ImageCtx; }
+
+namespace rbd {
+namespace mirror {
+namespace image_map {
+
+template<typename ImageCtxT = librbd::ImageCtx>
+class LoadRequest {
+public:
+  static LoadRequest *create(librados::IoCtx &ioctx,
+                             std::map<std::string, cls::rbd::MirrorImageMap> *image_mapping,
+                             Context *on_finish) {
+    return new LoadRequest(ioctx, image_mapping, on_finish);
+  }
+
+  void send();
+
+private:
+  /**
+   * @verbatim
+   *
+   *     <start>
+   *        |     . . . . . . . .
+   *        v     v             . MAX_RETURN
+   *  IMAGE_MAP_LIST. . . . . . .
+   *        |
+   *        v
+   *    <finish>
+   *
+   * @endverbatim
+   */
+  LoadRequest(librados::IoCtx &ioctx,
+              std::map<std::string, cls::rbd::MirrorImageMap> *image_mapping,
+              Context *on_finish);
+
+  librados::IoCtx &m_ioctx;
+  std::map<std::string, cls::rbd::MirrorImageMap> *m_image_mapping;
+  Context *m_on_finish;
+
+  bufferlist m_out_bl;
+  std::string m_start_after;
+
+  void image_map_list();
+  void handle_image_map_list(int r);
+
+  void finish(int r);
+};
+
+} // namespace image_map
+} // namespace mirror
+} // namespace rbd
+
+#endif // CEPH_RBD_MIRROR_IMAGE_MAP_LOAD_REQUEST_H

src/tools/rbd_mirror/image_map/UpdateRequest.cc

@@ -0,0 +1,100 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "common/debug.h"
+#include "common/errno.h"
+
+#include "librbd/Utils.h"
+#include "include/rbd_types.h"
+#include "cls/rbd/cls_rbd_client.h"
+
+#include "UpdateRequest.h"
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_rbd_mirror
+#undef dout_prefix
+#define dout_prefix *_dout << "rbd::mirror::image_map::UpdateRequest: "   \
+                           << this << " " << __func__
+
+namespace rbd {
+namespace mirror {
+namespace image_map {
+
+using librbd::util::create_rados_callback;
+
+static const uint32_t MAX_UPDATE = 256;
+
+template <typename I>
+UpdateRequest<I>::UpdateRequest(librados::IoCtx &ioctx,
+                                std::map<std::string, cls::rbd::MirrorImageMap> &&update_mapping,
+                                std::set<std::string> &&remove_global_image_ids, Context *on_finish)
+  : m_ioctx(ioctx),
+    m_update_mapping(update_mapping),
+    m_remove_global_image_ids(remove_global_image_ids),
+    m_on_finish(on_finish) {
+}
+
+template <typename I>
+void UpdateRequest<I>::send() {
+  dout(20) << dendl;
+
+  update_image_map();
+}
+
+template <typename I>
+void UpdateRequest<I>::update_image_map() {
+  dout(20) << dendl;
+
+  if (m_update_mapping.empty() && m_remove_global_image_ids.empty()) {
+    finish(0);
+    return;
+  }
+
+  uint32_t nr_updates = 0;
+  librados::ObjectWriteOperation op;
+
+  auto it1 = m_update_mapping.begin();
+  while (it1 != m_update_mapping.end() && nr_updates++ < MAX_UPDATE) {
+    librbd::cls_client::mirror_image_map_update(&op, it1->first, it1->second);
+    it1 = m_update_mapping.erase(it1);
+  }
+
+  auto it2 = m_remove_global_image_ids.begin();
+  while (it2 != m_remove_global_image_ids.end() && nr_updates++ < MAX_UPDATE) {
+    librbd::cls_client::mirror_image_map_remove(&op, *it2);
+    it2 = m_remove_global_image_ids.erase(it2);
+  }
+
+  librados::AioCompletion *aio_comp = create_rados_callback<
+    UpdateRequest, &UpdateRequest::handle_update_image_map>(this);
+  int r = m_ioctx.aio_operate(RBD_MIRROR_LEADER, aio_comp, &op);
+  assert(r == 0);
+  aio_comp->release();
+}
+
+template <typename I>
+void UpdateRequest<I>::handle_update_image_map(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  if (r < 0) {
+    derr << ": failed to update image map: " << cpp_strerror(r) << dendl;
+    finish(r);
+    return;
+  }
+
+  update_image_map();
+}
+
+template <typename I>
+void UpdateRequest<I>::finish(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  m_on_finish->complete(r);
+  delete this;
+}
+
+} // namespace image_map
+} // namespace mirror
+} // namespace rbd
+
+template class rbd::mirror::image_map::UpdateRequest<librbd::ImageCtx>;

src/tools/rbd_mirror/image_map/UpdateRequest.h

@@ -0,0 +1,65 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#ifndef CEPH_RBD_MIRROR_IMAGE_MAP_UPDATE_REQUEST_H
+#define CEPH_RBD_MIRROR_IMAGE_MAP_UPDATE_REQUEST_H
+
+#include "cls/rbd/cls_rbd_types.h"
+#include "include/rados/librados.hpp"
+
+class Context;
+
+namespace librbd { class ImageCtx; }
+
+namespace rbd {
+namespace mirror {
+namespace image_map {
+
+template<typename ImageCtxT = librbd::ImageCtx>
+class UpdateRequest {
+public:
+  // accepts an image map for updation and a collection of
+  // global image ids to purge.
+  static UpdateRequest *create(librados::IoCtx &ioctx,
+                               std::map<std::string, cls::rbd::MirrorImageMap> &&update_mapping,
+                               std::set<std::string> &&remove_global_image_ids, Context *on_finish) {
+    return new UpdateRequest(ioctx, std::move(update_mapping), std::move(remove_global_image_ids),
+                             on_finish);
+  }
+
+  void send();
+
+private:
+  /**
+   * @verbatim
+   *
+   *     <start>
+   *        |       . . . . . . . .
+   *        v       v             . MAX_UPDATE
+   *  UPDATE_IMAGE_MAP. . . . . . .
+   *        |
+   *        v
+   *    <finish>
+   *
+   * @endverbatim
+   */
+  UpdateRequest(librados::IoCtx &ioctx,
+                std::map<std::string, cls::rbd::MirrorImageMap> &&update_mapping,
+                std::set<std::string> &&remove_global_image_ids, Context *on_finish);
+
+  librados::IoCtx &m_ioctx;
+  std::map<std::string, cls::rbd::MirrorImageMap> m_update_mapping;
+  std::set<std::string> m_remove_global_image_ids;
+  Context *m_on_finish;
+
+  void update_image_map();
+  void handle_update_image_map(int r);
+
+  void finish(int r);
+};
+
+} // namespace image_map
+} // namespace mirror
+} // namespace rbd
+
+#endif // CEPH_RBD_MIRROR_IMAGE_MAP_UPDATE_REQUEST_H