initial code repo
[stor4nfv.git] / src / ceph / src / tools / rbd_mirror / ImageSync.cc
diff --git a/src/ceph/src/tools/rbd_mirror/ImageSync.cc b/src/ceph/src/tools/rbd_mirror/ImageSync.cc
new file mode 100644 (file)
index 0000000..644ee90
--- /dev/null
@@ -0,0 +1,410 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "ImageSync.h"
+#include "InstanceWatcher.h"
+#include "ProgressContext.h"
+#include "common/errno.h"
+#include "journal/Journaler.h"
+#include "librbd/ExclusiveLock.h"
+#include "librbd/ImageCtx.h"
+#include "librbd/ObjectMap.h"
+#include "librbd/Utils.h"
+#include "librbd/journal/Types.h"
+#include "tools/rbd_mirror/image_sync/ImageCopyRequest.h"
+#include "tools/rbd_mirror/image_sync/SnapshotCopyRequest.h"
+#include "tools/rbd_mirror/image_sync/SyncPointCreateRequest.h"
+#include "tools/rbd_mirror/image_sync/SyncPointPruneRequest.h"
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_rbd_mirror
+#undef dout_prefix
+#define dout_prefix *_dout << "rbd::mirror::ImageSync: " \
+                           << this << " " << __func__
+
+namespace rbd {
+namespace mirror {
+
+using namespace image_sync;
+using librbd::util::create_context_callback;
+using librbd::util::unique_lock_name;
+
+template <typename I>
+ImageSync<I>::ImageSync(I *local_image_ctx, I *remote_image_ctx,
+                        SafeTimer *timer, Mutex *timer_lock,
+                        const std::string &mirror_uuid, Journaler *journaler,
+                        MirrorPeerClientMeta *client_meta,
+                        ContextWQ *work_queue,
+                        InstanceWatcher<I> *instance_watcher,
+                        Context *on_finish, ProgressContext *progress_ctx)
+  : BaseRequest("rbd::mirror::ImageSync", local_image_ctx->cct, on_finish),
+    m_local_image_ctx(local_image_ctx), m_remote_image_ctx(remote_image_ctx),
+    m_timer(timer), m_timer_lock(timer_lock), m_mirror_uuid(mirror_uuid),
+    m_journaler(journaler), m_client_meta(client_meta),
+    m_work_queue(work_queue), m_instance_watcher(instance_watcher),
+    m_progress_ctx(progress_ctx),
+    m_lock(unique_lock_name("ImageSync::m_lock", this)) {
+}
+
+template <typename I>
+ImageSync<I>::~ImageSync() {
+  assert(m_snapshot_copy_request == nullptr);
+  assert(m_image_copy_request == nullptr);
+}
+
+template <typename I>
+void ImageSync<I>::send() {
+  send_notify_sync_request();
+}
+
+template <typename I>
+void ImageSync<I>::cancel() {
+  Mutex::Locker locker(m_lock);
+
+  dout(20) << dendl;
+
+  m_canceled = true;
+
+  if (m_instance_watcher->cancel_sync_request(m_local_image_ctx->id)) {
+    return;
+  }
+
+  if (m_snapshot_copy_request != nullptr) {
+    m_snapshot_copy_request->cancel();
+  }
+
+  if (m_image_copy_request != nullptr) {
+    m_image_copy_request->cancel();
+  }
+}
+
+template <typename I>
+void ImageSync<I>::send_notify_sync_request() {
+  update_progress("NOTIFY_SYNC_REQUEST");
+
+  dout(20) << dendl;
+
+  Context *ctx = create_context_callback<
+    ImageSync<I>, &ImageSync<I>::handle_notify_sync_request>(this);
+  m_instance_watcher->notify_sync_request(m_local_image_ctx->id, ctx);
+}
+
+template <typename I>
+void ImageSync<I>::handle_notify_sync_request(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  if (r < 0) {
+    BaseRequest::finish(r);
+    return;
+  }
+
+  send_prune_catch_up_sync_point();
+}
+
+template <typename I>
+void ImageSync<I>::send_prune_catch_up_sync_point() {
+  update_progress("PRUNE_CATCH_UP_SYNC_POINT");
+
+  if (m_client_meta->sync_points.empty()) {
+    send_create_sync_point();
+    return;
+  }
+
+  dout(20) << dendl;
+
+  // prune will remove sync points with missing snapshots and
+  // ensure we have a maximum of one sync point (in case we
+  // restarted)
+  Context *ctx = create_context_callback<
+    ImageSync<I>, &ImageSync<I>::handle_prune_catch_up_sync_point>(this);
+  SyncPointPruneRequest<I> *request = SyncPointPruneRequest<I>::create(
+    m_remote_image_ctx, false, m_journaler, m_client_meta, ctx);
+  request->send();
+}
+
+template <typename I>
+void ImageSync<I>::handle_prune_catch_up_sync_point(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  if (r < 0) {
+    derr << ": failed to prune catch-up sync point: "
+         << cpp_strerror(r) << dendl;
+    finish(r);
+    return;
+  }
+
+  send_create_sync_point();
+}
+
+template <typename I>
+void ImageSync<I>::send_create_sync_point() {
+  update_progress("CREATE_SYNC_POINT");
+
+  // TODO: when support for disconnecting laggy clients is added,
+  //       re-connect and create catch-up sync point
+  if (m_client_meta->sync_points.size() > 0) {
+    send_copy_snapshots();
+    return;
+  }
+
+  dout(20) << dendl;
+
+  Context *ctx = create_context_callback<
+    ImageSync<I>, &ImageSync<I>::handle_create_sync_point>(this);
+  SyncPointCreateRequest<I> *request = SyncPointCreateRequest<I>::create(
+    m_remote_image_ctx, m_mirror_uuid, m_journaler, m_client_meta, ctx);
+  request->send();
+}
+
+template <typename I>
+void ImageSync<I>::handle_create_sync_point(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  if (r < 0) {
+    derr << ": failed to create sync point: " << cpp_strerror(r)
+         << dendl;
+    finish(r);
+    return;
+  }
+
+  send_copy_snapshots();
+}
+
+template <typename I>
+void ImageSync<I>::send_copy_snapshots() {
+  m_lock.Lock();
+  if (m_canceled) {
+    m_lock.Unlock();
+    finish(-ECANCELED);
+    return;
+  }
+
+  dout(20) << dendl;
+
+  Context *ctx = create_context_callback<
+    ImageSync<I>, &ImageSync<I>::handle_copy_snapshots>(this);
+  m_snapshot_copy_request = SnapshotCopyRequest<I>::create(
+    m_local_image_ctx, m_remote_image_ctx, &m_snap_map, m_journaler,
+    m_client_meta, m_work_queue, ctx);
+  m_snapshot_copy_request->get();
+  m_lock.Unlock();
+
+  update_progress("COPY_SNAPSHOTS");
+
+  m_snapshot_copy_request->send();
+}
+
+template <typename I>
+void ImageSync<I>::handle_copy_snapshots(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  {
+    Mutex::Locker locker(m_lock);
+    m_snapshot_copy_request->put();
+    m_snapshot_copy_request = nullptr;
+    if (r == 0 && m_canceled) {
+      r = -ECANCELED;
+    }
+  }
+
+  if (r == -ECANCELED) {
+    dout(10) << ": snapshot copy canceled" << dendl;
+    finish(r);
+    return;
+  } else if (r < 0) {
+    derr << ": failed to copy snapshot metadata: " << cpp_strerror(r) << dendl;
+    finish(r);
+    return;
+  }
+
+  send_copy_image();
+}
+
+template <typename I>
+void ImageSync<I>::send_copy_image() {
+  m_lock.Lock();
+  if (m_canceled) {
+    m_lock.Unlock();
+    finish(-ECANCELED);
+    return;
+  }
+
+  dout(20) << dendl;
+
+  Context *ctx = create_context_callback<
+    ImageSync<I>, &ImageSync<I>::handle_copy_image>(this);
+  m_image_copy_request = ImageCopyRequest<I>::create(
+    m_local_image_ctx, m_remote_image_ctx, m_timer, m_timer_lock,
+    m_journaler, m_client_meta, &m_client_meta->sync_points.front(),
+    ctx, m_progress_ctx);
+  m_image_copy_request->get();
+  m_lock.Unlock();
+
+  update_progress("COPY_IMAGE");
+
+  m_image_copy_request->send();
+}
+
+template <typename I>
+void ImageSync<I>::handle_copy_image(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  {
+    Mutex::Locker locker(m_lock);
+    m_image_copy_request->put();
+    m_image_copy_request = nullptr;
+    if (r == 0 && m_canceled) {
+      r = -ECANCELED;
+    }
+  }
+
+  if (r == -ECANCELED) {
+    dout(10) << ": image copy canceled" << dendl;
+    finish(r);
+    return;
+  } else if (r < 0) {
+    derr << ": failed to copy image: " << cpp_strerror(r) << dendl;
+    finish(r);
+    return;
+  }
+
+  send_copy_object_map();
+}
+
+template <typename I>
+void ImageSync<I>::send_copy_object_map() {
+  update_progress("COPY_OBJECT_MAP");
+
+  m_local_image_ctx->owner_lock.get_read();
+  m_local_image_ctx->snap_lock.get_read();
+  if (!m_local_image_ctx->test_features(RBD_FEATURE_OBJECT_MAP,
+                                        m_local_image_ctx->snap_lock)) {
+    m_local_image_ctx->snap_lock.put_read();
+    m_local_image_ctx->owner_lock.put_read();
+    send_prune_sync_points();
+    return;
+  }
+
+  assert(m_local_image_ctx->object_map != nullptr);
+
+  assert(!m_client_meta->sync_points.empty());
+  librbd::journal::MirrorPeerSyncPoint &sync_point =
+    m_client_meta->sync_points.front();
+  auto snap_id_it = m_local_image_ctx->snap_ids.find(
+    {cls::rbd::UserSnapshotNamespace(), sync_point.snap_name});
+  assert(snap_id_it != m_local_image_ctx->snap_ids.end());
+  librados::snap_t snap_id = snap_id_it->second;
+
+  dout(20) << ": snap_id=" << snap_id << ", "
+           << "snap_name=" << sync_point.snap_name << dendl;
+
+  Context *finish_op_ctx = nullptr;
+  if (m_local_image_ctx->exclusive_lock != nullptr) {
+    finish_op_ctx = m_local_image_ctx->exclusive_lock->start_op();
+  }
+  if (finish_op_ctx == nullptr) {
+    derr << ": lost exclusive lock" << dendl;
+    m_local_image_ctx->snap_lock.put_read();
+    m_local_image_ctx->owner_lock.put_read();
+    finish(-EROFS);
+    return;
+  }
+
+  // rollback the object map (copy snapshot object map to HEAD)
+  RWLock::WLocker object_map_locker(m_local_image_ctx->object_map_lock);
+  auto ctx = new FunctionContext([this, finish_op_ctx](int r) {
+      handle_copy_object_map(r);
+      finish_op_ctx->complete(0);
+    });
+  m_local_image_ctx->object_map->rollback(snap_id, ctx);
+  m_local_image_ctx->snap_lock.put_read();
+  m_local_image_ctx->owner_lock.put_read();
+}
+
+template <typename I>
+void ImageSync<I>::handle_copy_object_map(int r) {
+  dout(20) << dendl;
+
+  assert(r == 0);
+  send_refresh_object_map();
+}
+
+template <typename I>
+void ImageSync<I>::send_refresh_object_map() {
+  dout(20) << dendl;
+
+  update_progress("REFRESH_OBJECT_MAP");
+
+  Context *ctx = create_context_callback<
+    ImageSync<I>, &ImageSync<I>::handle_refresh_object_map>(this);
+  m_object_map = m_local_image_ctx->create_object_map(CEPH_NOSNAP);
+  m_object_map->open(ctx);
+}
+
+template <typename I>
+void ImageSync<I>::handle_refresh_object_map(int r) {
+  dout(20) << dendl;
+
+  assert(r == 0);
+  {
+    RWLock::WLocker snap_locker(m_local_image_ctx->snap_lock);
+    std::swap(m_local_image_ctx->object_map, m_object_map);
+  }
+  delete m_object_map;
+
+  send_prune_sync_points();
+}
+
+template <typename I>
+void ImageSync<I>::send_prune_sync_points() {
+  dout(20) << dendl;
+
+  update_progress("PRUNE_SYNC_POINTS");
+
+  Context *ctx = create_context_callback<
+    ImageSync<I>, &ImageSync<I>::handle_prune_sync_points>(this);
+  SyncPointPruneRequest<I> *request = SyncPointPruneRequest<I>::create(
+    m_remote_image_ctx, true, m_journaler, m_client_meta, ctx);
+  request->send();
+}
+
+template <typename I>
+void ImageSync<I>::handle_prune_sync_points(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  if (r < 0) {
+    derr << ": failed to prune sync point: "
+         << cpp_strerror(r) << dendl;
+    finish(r);
+    return;
+  }
+
+  if (!m_client_meta->sync_points.empty()) {
+    send_copy_image();
+    return;
+  }
+
+  finish(0);
+}
+
+template <typename I>
+void ImageSync<I>::update_progress(const std::string &description) {
+  dout(20) << ": " << description << dendl;
+
+  if (m_progress_ctx) {
+    m_progress_ctx->update_progress("IMAGE_SYNC/" + description);
+  }
+}
+
+template <typename I>
+void ImageSync<I>::finish(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  m_instance_watcher->notify_sync_complete(m_local_image_ctx->id);
+  BaseRequest::finish(r);
+}
+
+} // namespace mirror
+} // namespace rbd
+
+template class rbd::mirror::ImageSync<librbd::ImageCtx>;