X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=src%2Fceph%2Fsrc%2Ftools%2Frbd_mirror%2Fimage_replayer%2FOpenLocalImageRequest.cc;fp=src%2Fceph%2Fsrc%2Ftools%2Frbd_mirror%2Fimage_replayer%2FOpenLocalImageRequest.cc;h=a54216a8328cab410591fa983bb9111babb7dd57;hb=812ff6ca9fcd3e629e49d4328905f33eee8ca3f5;hp=0000000000000000000000000000000000000000;hpb=15280273faafb77777eab341909a3f495cf248d9;p=stor4nfv.git

diff --git a/src/ceph/src/tools/rbd_mirror/image_replayer/OpenLocalImageRequest.cc b/src/ceph/src/tools/rbd_mirror/image_replayer/OpenLocalImageRequest.cc
new file mode 100644
index 0000000..a54216a
--- /dev/null
+++ b/src/ceph/src/tools/rbd_mirror/image_replayer/OpenLocalImageRequest.cc
@@ -0,0 +1,254 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "include/compat.h"
+#include "CloseImageRequest.h"
+#include "IsPrimaryRequest.h"
+#include "OpenLocalImageRequest.h"
+#include "common/errno.h"
+#include "common/WorkQueue.h"
+#include "librbd/ExclusiveLock.h"
+#include "librbd/ImageCtx.h"
+#include "librbd/ImageState.h"
+#include "librbd/Journal.h"
+#include "librbd/Utils.h"
+#include "librbd/exclusive_lock/Policy.h"
+#include "librbd/journal/Policy.h"
+#include <type_traits>
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_rbd_mirror
+#undef dout_prefix
+#define dout_prefix *_dout << "rbd::mirror::image_replayer::OpenLocalImageRequest: " \
+                           << this << " " << __func__ << " "
+
+namespace rbd {
+namespace mirror {
+namespace image_replayer {
+
+using librbd::util::create_context_callback;
+
+namespace {
+
+template <typename I>
+struct MirrorExclusiveLockPolicy : public librbd::exclusive_lock::Policy {
+  I *image_ctx;
+
+  MirrorExclusiveLockPolicy(I *image_ctx) : image_ctx(image_ctx) {
+  }
+
+  bool may_auto_request_lock() override {
+    return false;
+  }
+
+  int lock_requested(bool force) override {
+    int r = -EROFS;
+    {
+      RWLock::RLocker owner_locker(image_ctx->owner_lock);
+      RWLock::RLocker snap_locker(image_ctx->snap_lock);
+      if (image_ctx->journal == nullptr || image_ctx->journal->is_tag_owner()) {
+        r = 0;
+      }
+    }
+
+    if (r == 0) {
+      // if the local image journal has been closed or if it was (force)
+      // promoted allow the lock to be released to another client
+      image_ctx->exclusive_lock->release_lock(nullptr);
+    }
+    return r;
+  }
+
+};
+
+struct MirrorJournalPolicy : public librbd::journal::Policy {
+  ContextWQ *work_queue;
+
+  MirrorJournalPolicy(ContextWQ *work_queue) : work_queue(work_queue) {
+  }
+
+  bool append_disabled() const override {
+    // avoid recording any events to the local journal
+    return true;
+  }
+  bool journal_disabled() const override {
+    return false;
+  }
+
+  void allocate_tag_on_lock(Context *on_finish) override {
+    // rbd-mirror will manually create tags by copying them from the peer
+    work_queue->queue(on_finish, 0);
+  }
+};
+
+} // anonymous namespace
+
+template <typename I>
+OpenLocalImageRequest<I>::OpenLocalImageRequest(librados::IoCtx &local_io_ctx,
+                                                I **local_image_ctx,
+                                                const std::string &local_image_id,
+                                                ContextWQ *work_queue,
+                                                Context *on_finish)
+  : m_local_io_ctx(local_io_ctx), m_local_image_ctx(local_image_ctx),
+    m_local_image_id(local_image_id), m_work_queue(work_queue),
+    m_on_finish(on_finish) {
+}
+
+template <typename I>
+void OpenLocalImageRequest<I>::send() {
+  send_open_image();
+}
+
+template <typename I>
+void OpenLocalImageRequest<I>::send_open_image() {
+  dout(20) << dendl;
+
+  *m_local_image_ctx = I::create("", m_local_image_id, nullptr,
+                                 m_local_io_ctx, false);
+  {
+    RWLock::WLocker owner_locker((*m_local_image_ctx)->owner_lock);
+    RWLock::WLocker snap_locker((*m_local_image_ctx)->snap_lock);
+    (*m_local_image_ctx)->set_exclusive_lock_policy(
+      new MirrorExclusiveLockPolicy<I>(*m_local_image_ctx));
+    (*m_local_image_ctx)->set_journal_policy(
+      new MirrorJournalPolicy(m_work_queue));
+  }
+
+  Context *ctx = create_context_callback<
+    OpenLocalImageRequest<I>, &OpenLocalImageRequest<I>::handle_open_image>(
+      this);
+  (*m_local_image_ctx)->state->open(false, ctx);
+}
+
+template <typename I>
+void OpenLocalImageRequest<I>::handle_open_image(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  if (r < 0) {
+    derr << ": failed to open image '" << m_local_image_id << "': "
+         << cpp_strerror(r) << dendl;
+    (*m_local_image_ctx)->destroy();
+    *m_local_image_ctx = nullptr;
+    finish(r);
+    return;
+  }
+
+  send_is_primary();
+}
+
+template <typename I>
+void OpenLocalImageRequest<I>::send_is_primary() {
+  dout(20) << dendl;
+
+  Context *ctx = create_context_callback<
+    OpenLocalImageRequest<I>, &OpenLocalImageRequest<I>::handle_is_primary>(
+      this);
+  IsPrimaryRequest<I> *request = IsPrimaryRequest<I>::create(*m_local_image_ctx,
+                                                             &m_primary, ctx);
+  request->send();
+}
+
+template <typename I>
+void OpenLocalImageRequest<I>::handle_is_primary(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  if (r < 0) {
+    derr << ": error querying local image primary status: " << cpp_strerror(r)
+         << dendl;
+    send_close_image(r);
+    return;
+  }
+
+  // if the local image owns the tag -- don't steal the lock since
+  // we aren't going to mirror peer data into this image anyway
+  if (m_primary) {
+    dout(10) << ": local image is primary -- skipping image replay" << dendl;
+    send_close_image(-EREMOTEIO);
+    return;
+  }
+
+  send_lock_image();
+}
+
+template <typename I>
+void OpenLocalImageRequest<I>::send_lock_image() {
+  dout(20) << dendl;
+
+  RWLock::RLocker owner_locker((*m_local_image_ctx)->owner_lock);
+  if ((*m_local_image_ctx)->exclusive_lock == nullptr) {
+    derr << ": image does not support exclusive lock" << dendl;
+    send_close_image(-EINVAL);
+    return;
+  }
+
+  // disallow any proxied maintenance operations before grabbing lock
+  (*m_local_image_ctx)->exclusive_lock->block_requests(-EROFS);
+
+  Context *ctx = create_context_callback<
+    OpenLocalImageRequest<I>, &OpenLocalImageRequest<I>::handle_lock_image>(
+      this);
+
+  (*m_local_image_ctx)->exclusive_lock->acquire_lock(ctx);
+}
+
+template <typename I>
+void OpenLocalImageRequest<I>::handle_lock_image(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  if (r < 0) {
+    derr << ": failed to lock image '" << m_local_image_id << "': "
+       << cpp_strerror(r) << dendl;
+    send_close_image(r);
+    return;
+  }
+
+  {
+    RWLock::RLocker owner_locker((*m_local_image_ctx)->owner_lock);
+    if ((*m_local_image_ctx)->exclusive_lock == nullptr ||
+	!(*m_local_image_ctx)->exclusive_lock->is_lock_owner()) {
+      derr << ": image is not locked" << dendl;
+      send_close_image(-EBUSY);
+      return;
+    }
+  }
+
+  finish(0);
+}
+
+template <typename I>
+void OpenLocalImageRequest<I>::send_close_image(int r) {
+  dout(20) << dendl;
+
+  if (m_ret_val == 0 && r < 0) {
+    m_ret_val = r;
+  }
+
+  Context *ctx = create_context_callback<
+    OpenLocalImageRequest<I>, &OpenLocalImageRequest<I>::handle_close_image>(
+      this);
+  CloseImageRequest<I> *request = CloseImageRequest<I>::create(
+    m_local_image_ctx, ctx);
+  request->send();
+}
+
+template <typename I>
+void OpenLocalImageRequest<I>::handle_close_image(int r) {
+  dout(20) << dendl;
+
+  assert(r == 0);
+  finish(m_ret_val);
+}
+
+template <typename I>
+void OpenLocalImageRequest<I>::finish(int r) {
+  dout(20) << ": r=" << r << dendl;
+
+  m_on_finish->complete(r);
+  delete this;
+}
+
+} // namespace image_replayer
+} // namespace mirror
+} // namespace rbd
+
+template class rbd::mirror::image_replayer::OpenLocalImageRequest<librbd::ImageCtx>;