1 files changed, 255 insertions, 0 deletions
diff --git a/src/librbd/journal/DemoteRequest.cc b/src/librbd/journal/DemoteRequest.cc
new file mode 100644
index 000000000..564391978
--- /dev/null
+++ b/src/librbd/journal/DemoteRequest.cc
@@ -0,0 +1,255 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "librbd/journal/DemoteRequest.h"
+#include "common/dout.h"
+#include "common/errno.h"
+#include "journal/Journaler.h"
+#include "journal/Settings.h"
+#include "librbd/ImageCtx.h"
+#include "librbd/Journal.h"
+#include "librbd/Utils.h"
+#include "librbd/asio/ContextWQ.h"
+#include "librbd/journal/OpenRequest.h"
+
+#define dout_subsys ceph_subsys_rbd
+#undef dout_prefix
+#define dout_prefix *_dout << "librbd::journal::DemoteRequest: " << this \
+                           << " " << __func__ << ": "
+
+namespace librbd {
+namespace journal {
+
+using librbd::util::create_async_context_callback;
+using librbd::util::create_context_callback;
+
+template <typename I>
+DemoteRequest<I>::DemoteRequest(I &image_ctx, Context *on_finish)
+  : m_image_ctx(image_ctx), m_on_finish(on_finish),
+    m_lock(ceph::make_mutex("DemoteRequest::m_lock")) {
+}
+
+template <typename I>
+DemoteRequest<I>::~DemoteRequest() {
+  ceph_assert(m_journaler == nullptr);
+}
+
+template <typename I>
+void DemoteRequest<I>::send() {
+  open_journaler();
+}
+
+template <typename I>
+void DemoteRequest<I>::open_journaler() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << dendl;
+
+  m_journaler = new Journaler(m_image_ctx.md_ctx, m_image_ctx.id,
+                              Journal<>::IMAGE_CLIENT_ID, {}, nullptr);
+  auto ctx = create_async_context_callback(
+    m_image_ctx, create_context_callback<
+      DemoteRequest<I>, &DemoteRequest<I>::handle_open_journaler>(this));
+  auto req = OpenRequest<I>::create(&m_image_ctx, m_journaler, &m_lock,
+                                    &m_client_meta, &m_tag_tid, &m_tag_data,
+                                    ctx);
+  req->send();
+}
+
+template <typename I>
+void DemoteRequest<I>::handle_open_journaler(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << "r=" << r << dendl;
+
+  if (r < 0) {
+    m_ret_val = r;
+    lderr(cct) << "failed to open journal: " << cpp_strerror(r) << dendl;
+    shut_down_journaler();
+    return;
+  } else if (m_tag_data.mirror_uuid != Journal<>::LOCAL_MIRROR_UUID) {
+    m_ret_val = -EINVAL;
+    lderr(cct) << "image is not currently the primary" << dendl;
+    shut_down_journaler();
+    return;
+  }
+
+  allocate_tag();
+}
+
+template <typename I>
+void DemoteRequest<I>::allocate_tag() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << dendl;
+
+  cls::journal::Client client;
+  int r = m_journaler->get_cached_client(Journal<>::IMAGE_CLIENT_ID, &client);
+  if (r < 0) {
+    m_ret_val = r;
+    lderr(cct) << "failed to retrieve client: " << cpp_strerror(r) << dendl;
+    shut_down_journaler();
+    return;
+  }
+
+  TagPredecessor predecessor;
+  predecessor.mirror_uuid = Journal<>::LOCAL_MIRROR_UUID;
+  if (!client.commit_position.object_positions.empty()) {
+    auto position = client.commit_position.object_positions.front();
+    predecessor.commit_valid = true;
+    predecessor.tag_tid = position.tag_tid;
+    predecessor.entry_tid = position.entry_tid;
+  }
+
+  TagData tag_data;
+  tag_data.mirror_uuid = Journal<>::ORPHAN_MIRROR_UUID;
+  tag_data.predecessor = std::move(predecessor);
+
+  bufferlist tag_bl;
+  encode(tag_data, tag_bl);
+
+  auto ctx = create_context_callback<
+    DemoteRequest<I>, &DemoteRequest<I>::handle_allocate_tag>(this);
+  m_journaler->allocate_tag(m_client_meta.tag_class, tag_bl, &m_tag, ctx);
+}
+
+template <typename I>
+void DemoteRequest<I>::handle_allocate_tag(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << "r=" << r << dendl;
+
+  if (r < 0) {
+    m_ret_val = r;
+    lderr(cct) << "failed to allocate tag: " << cpp_strerror(r) << dendl;
+    shut_down_journaler();
+    return;
+  }
+
+  m_tag_tid = m_tag.tid;
+  append_event();
+}
+
+template <typename I>
+void DemoteRequest<I>::append_event() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << dendl;
+
+  EventEntry event_entry{DemotePromoteEvent{}, {}};
+  bufferlist event_entry_bl;
+  encode(event_entry, event_entry_bl);
+
+  m_journaler->start_append(0);
+  m_future = m_journaler->append(m_tag_tid, event_entry_bl);
+
+  auto ctx = create_context_callback<
+    DemoteRequest<I>, &DemoteRequest<I>::handle_append_event>(this);
+  m_future.flush(ctx);
+
+}
+
+template <typename I>
+void DemoteRequest<I>::handle_append_event(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << "r=" << r << dendl;
+
+  if (r < 0) {
+    m_ret_val = r;
+    lderr(cct) << "failed to append demotion journal event: " << cpp_strerror(r)
+               << dendl;
+    stop_append();
+    return;
+  }
+
+  commit_event();
+}
+
+template <typename I>
+void DemoteRequest<I>::commit_event() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << dendl;
+
+  m_journaler->committed(m_future);
+
+  auto ctx = create_context_callback<
+    DemoteRequest<I>, &DemoteRequest<I>::handle_commit_event>(this);
+  m_journaler->flush_commit_position(ctx);
+}
+
+template <typename I>
+void DemoteRequest<I>::handle_commit_event(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << "r=" << r << dendl;
+
+  if (r < 0) {
+    m_ret_val = r;
+    lderr(cct) << "failed to flush demotion commit position: "
+               << cpp_strerror(r) << dendl;
+  }
+
+  stop_append();
+}
+
+template <typename I>
+void DemoteRequest<I>::stop_append() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << dendl;
+
+  auto ctx = create_context_callback<
+    DemoteRequest<I>, &DemoteRequest<I>::handle_stop_append>(this);
+  m_journaler->stop_append(ctx);
+}
+
+template <typename I>
+void DemoteRequest<I>::handle_stop_append(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << "r=" << r << dendl;
+
+  if (r < 0) {
+    if (m_ret_val == 0) {
+      m_ret_val = r;
+    }
+    lderr(cct) << "failed to stop journal append: " << cpp_strerror(r) << dendl;
+  }
+
+  shut_down_journaler();
+}
+
+template <typename I>
+void DemoteRequest<I>::shut_down_journaler() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << dendl;
+
+  Context *ctx = create_async_context_callback(
+    m_image_ctx, create_context_callback<
+      DemoteRequest<I>, &DemoteRequest<I>::handle_shut_down_journaler>(this));
+  m_journaler->shut_down(ctx);
+}
+
+template <typename I>
+void DemoteRequest<I>::handle_shut_down_journaler(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << "r=" << r << dendl;
+
+  if (r < 0) {
+    lderr(cct) << "failed to shut down journal: " << cpp_strerror(r) << dendl;
+  }
+
+  delete m_journaler;
+  m_journaler = nullptr;
+  finish(r);
+}
+
+template <typename I>
+void DemoteRequest<I>::finish(int r) {
+  if (m_ret_val < 0) {
+    r = m_ret_val;
+  }
+
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 20) << "r=" << r << dendl;
+
+  m_on_finish->complete(r);
+  delete this;
+}
+
+} // namespace journal
+} // namespace librbd
+
+template class librbd::journal::DemoteRequest<librbd::ImageCtx>;