1 files changed, 299 insertions, 0 deletions
diff --git a/src/librbd/exclusive_lock/PreReleaseRequest.cc b/src/librbd/exclusive_lock/PreReleaseRequest.cc
new file mode 100644
index 00000000..7dbae6c5
--- /dev/null
+++ b/src/librbd/exclusive_lock/PreReleaseRequest.cc
@@ -0,0 +1,299 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "librbd/exclusive_lock/PreReleaseRequest.h"
+#include "common/AsyncOpTracker.h"
+#include "common/dout.h"
+#include "common/errno.h"
+#include "librbd/ExclusiveLock.h"
+#include "librbd/ImageState.h"
+#include "librbd/ImageWatcher.h"
+#include "librbd/Journal.h"
+#include "librbd/ObjectMap.h"
+#include "librbd/Utils.h"
+#include "librbd/io/ImageRequestWQ.h"
+#include "librbd/io/ObjectDispatcher.h"
+
+#define dout_subsys ceph_subsys_rbd
+#undef dout_prefix
+#define dout_prefix *_dout << "librbd::exclusive_lock::PreReleaseRequest: " \
+                           << this << " " << __func__ << ": "
+
+namespace librbd {
+namespace exclusive_lock {
+
+using util::create_async_context_callback;
+using util::create_context_callback;
+
+template <typename I>
+PreReleaseRequest<I>* PreReleaseRequest<I>::create(
+    I &image_ctx, bool shutting_down, AsyncOpTracker &async_op_tracker,
+    Context *on_finish) {
+  return new PreReleaseRequest(image_ctx, shutting_down, async_op_tracker,
+                               on_finish);
+}
+
+template <typename I>
+PreReleaseRequest<I>::PreReleaseRequest(I &image_ctx, bool shutting_down,
+                                        AsyncOpTracker &async_op_tracker,
+                                        Context *on_finish)
+  : m_image_ctx(image_ctx), m_shutting_down(shutting_down),
+    m_async_op_tracker(async_op_tracker),
+    m_on_finish(create_async_context_callback(image_ctx, on_finish)) {
+}
+
+template <typename I>
+PreReleaseRequest<I>::~PreReleaseRequest() {
+  if (!m_shutting_down) {
+    m_image_ctx.state->handle_prepare_lock_complete();
+  }
+}
+
+template <typename I>
+void PreReleaseRequest<I>::send() {
+  send_prepare_lock();
+}
+
+template <typename I>
+void PreReleaseRequest<I>::send_prepare_lock() {
+  if (m_shutting_down) {
+    send_cancel_op_requests();
+    return;
+  }
+
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  // release the lock if the image is not busy performing other actions
+  Context *ctx = create_context_callback<
+    PreReleaseRequest<I>, &PreReleaseRequest<I>::handle_prepare_lock>(this);
+  m_image_ctx.state->prepare_lock(ctx);
+}
+
+template <typename I>
+void PreReleaseRequest<I>::handle_prepare_lock(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << "r=" << r << dendl;
+
+  send_cancel_op_requests();
+}
+
+template <typename I>
+void PreReleaseRequest<I>::send_cancel_op_requests() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  using klass = PreReleaseRequest<I>;
+  Context *ctx = create_context_callback<
+    klass, &klass::handle_cancel_op_requests>(this);
+  m_image_ctx.cancel_async_requests(ctx);
+}
+
+template <typename I>
+void PreReleaseRequest<I>::handle_cancel_op_requests(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << "r=" << r << dendl;
+
+  ceph_assert(r == 0);
+
+  send_block_writes();
+}
+
+template <typename I>
+void PreReleaseRequest<I>::send_block_writes() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  using klass = PreReleaseRequest<I>;
+  Context *ctx = create_context_callback<
+    klass, &klass::handle_block_writes>(this);
+
+  {
+    RWLock::RLocker owner_locker(m_image_ctx.owner_lock);
+    // setting the lock as required will automatically cause the IO
+    // queue to re-request the lock if any IO is queued
+    if (m_image_ctx.clone_copy_on_read ||
+        m_image_ctx.test_features(RBD_FEATURE_JOURNALING)) {
+      m_image_ctx.io_work_queue->set_require_lock(io::DIRECTION_BOTH, true);
+    } else {
+      m_image_ctx.io_work_queue->set_require_lock(io::DIRECTION_WRITE, true);
+    }
+    m_image_ctx.io_work_queue->block_writes(ctx);
+  }
+}
+
+template <typename I>
+void PreReleaseRequest<I>::handle_block_writes(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << "r=" << r << dendl;
+
+  if (r == -EBLACKLISTED) {
+    // allow clean shut down if blacklisted
+    lderr(cct) << "failed to block writes because client is blacklisted"
+               << dendl;
+  } else if (r < 0) {
+    lderr(cct) << "failed to block writes: " << cpp_strerror(r) << dendl;
+    m_image_ctx.io_work_queue->unblock_writes();
+    save_result(r);
+    finish();
+    return;
+  }
+
+  send_wait_for_ops();
+}
+
+template <typename I>
+void PreReleaseRequest<I>::send_wait_for_ops() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  Context *ctx = create_context_callback<
+    PreReleaseRequest<I>, &PreReleaseRequest<I>::handle_wait_for_ops>(this);
+  m_async_op_tracker.wait_for_ops(ctx);
+}
+
+template <typename I>
+void PreReleaseRequest<I>::handle_wait_for_ops(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  send_invalidate_cache();
+}
+
+template <typename I>
+void PreReleaseRequest<I>::send_invalidate_cache() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  RWLock::RLocker owner_lock(m_image_ctx.owner_lock);
+  Context *ctx = create_context_callback<
+      PreReleaseRequest<I>,
+      &PreReleaseRequest<I>::handle_invalidate_cache>(this);
+  m_image_ctx.io_object_dispatcher->invalidate_cache(ctx);
+}
+
+template <typename I>
+void PreReleaseRequest<I>::handle_invalidate_cache(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << "r=" << r << dendl;
+
+  if (r < 0 && r != -EBLACKLISTED && r != -EBUSY) {
+    lderr(cct) << "failed to invalidate cache: " << cpp_strerror(r)
+               << dendl;
+    m_image_ctx.io_work_queue->unblock_writes();
+    save_result(r);
+    finish();
+    return;
+  }
+
+  send_flush_notifies();
+}
+
+template <typename I>
+void PreReleaseRequest<I>::send_flush_notifies() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  using klass = PreReleaseRequest<I>;
+  Context *ctx =
+    create_context_callback<klass, &klass::handle_flush_notifies>(this);
+  m_image_ctx.image_watcher->flush(ctx);
+}
+
+template <typename I>
+void PreReleaseRequest<I>::handle_flush_notifies(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  ceph_assert(r == 0);
+  send_close_journal();
+}
+
+template <typename I>
+void PreReleaseRequest<I>::send_close_journal() {
+  {
+    RWLock::WLocker snap_locker(m_image_ctx.snap_lock);
+    std::swap(m_journal, m_image_ctx.journal);
+  }
+
+  if (m_journal == nullptr) {
+    send_close_object_map();
+    return;
+  }
+
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  using klass = PreReleaseRequest<I>;
+  Context *ctx = create_context_callback<klass, &klass::handle_close_journal>(
+    this);
+  m_journal->close(ctx);
+}
+
+template <typename I>
+void PreReleaseRequest<I>::handle_close_journal(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << "r=" << r << dendl;
+
+  if (r < 0) {
+    // error implies some journal events were not flushed -- continue
+    lderr(cct) << "failed to close journal: " << cpp_strerror(r) << dendl;
+  }
+
+  delete m_journal;
+
+  send_close_object_map();
+}
+
+template <typename I>
+void PreReleaseRequest<I>::send_close_object_map() {
+  {
+    RWLock::WLocker snap_locker(m_image_ctx.snap_lock);
+    std::swap(m_object_map, m_image_ctx.object_map);
+  }
+
+  if (m_object_map == nullptr) {
+    send_unlock();
+    return;
+  }
+
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  using klass = PreReleaseRequest<I>;
+  Context *ctx = create_context_callback<
+    klass, &klass::handle_close_object_map>(this);
+  m_object_map->close(ctx);
+}
+
+template <typename I>
+void PreReleaseRequest<I>::handle_close_object_map(int r) {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << "r=" << r << dendl;
+
+  if (r < 0) {
+    lderr(cct) << "failed to close object map: " << cpp_strerror(r) << dendl;
+  }
+
+  delete m_object_map;
+  send_unlock();
+}
+
+template <typename I>
+void PreReleaseRequest<I>::send_unlock() {
+  CephContext *cct = m_image_ctx.cct;
+  ldout(cct, 10) << dendl;
+
+  finish();
+}
+
+template <typename I>
+void PreReleaseRequest<I>::finish() {
+  m_on_finish->complete(m_error_result);
+  delete this;
+}
+
+} // namespace exclusive_lock
+} // namespace librbd
+
+template class librbd::exclusive_lock::PreReleaseRequest<librbd::ImageCtx>;