Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

6 files changed, 1902 insertions, 0 deletions

diff --git a/src/test/librbd/mirror/snapshot/test_mock_CreateNonPrimaryRequest.cc b/src/test/librbd/mirror/snapshot/test_mock_CreateNonPrimaryRequest.cc
new file mode 100644
index 000000000..d7e70cab7
--- /dev/null
+++ b/src/test/librbd/mirror/snapshot/test_mock_CreateNonPrimaryRequest.cc
@@ -0,0 +1,388 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "test/librbd/test_mock_fixture.h"
+#include "test/librbd/test_support.h"
+#include "test/librbd/mock/MockImageCtx.h"
+#include "test/librbd/mock/MockOperations.h"
+#include "test/librados_test_stub/MockTestMemIoCtxImpl.h"
+#include "test/librados_test_stub/MockTestMemRadosClient.h"
+#include "librbd/mirror/snapshot/CreateNonPrimaryRequest.h"
+#include "librbd/mirror/snapshot/Utils.h"
+#include "librbd/mirror/snapshot/WriteImageStateRequest.h"
+
+namespace librbd {
+
+namespace {
+
+struct MockTestImageCtx : public MockImageCtx {
+  explicit MockTestImageCtx(librbd::ImageCtx& image_ctx) : MockImageCtx(image_ctx) {
+  }
+};
+
+} // anonymous namespace
+
+namespace mirror {
+namespace snapshot {
+namespace util {
+
+namespace {
+
+struct Mock {
+  static Mock* s_instance;
+
+  Mock() {
+    s_instance = this;
+  }
+
+  MOCK_METHOD1(can_create_non_primary_snapshot,
+               bool(librbd::MockTestImageCtx *));
+};
+
+Mock *Mock::s_instance = nullptr;
+
+} // anonymous namespace
+
+template<> bool can_create_non_primary_snapshot(
+    librbd::MockTestImageCtx *image_ctx) {
+  return Mock::s_instance->can_create_non_primary_snapshot(image_ctx);
+}
+
+} // namespace util
+
+template <>
+struct WriteImageStateRequest<MockTestImageCtx> {
+  uint64_t snap_id = CEPH_NOSNAP;
+  ImageState image_state;
+  Context* on_finish = nullptr;
+  static WriteImageStateRequest* s_instance;
+  static WriteImageStateRequest *create(MockTestImageCtx *image_ctx,
+                                        uint64_t snap_id,
+                                        const ImageState &image_state,
+                                        Context *on_finish) {
+    ceph_assert(s_instance != nullptr);
+    s_instance->snap_id = snap_id;
+    s_instance->image_state = image_state;
+    s_instance->on_finish = on_finish;
+    return s_instance;
+  }
+
+  MOCK_METHOD0(send, void());
+
+  WriteImageStateRequest() {
+    s_instance = this;
+  }
+};
+
+WriteImageStateRequest<MockTestImageCtx>* WriteImageStateRequest<MockTestImageCtx>::s_instance = nullptr;
+
+} // namespace snapshot
+} // namespace mirror
+} // namespace librbd
+
+// template definitions
+#include "librbd/mirror/snapshot/CreateNonPrimaryRequest.cc"
+template class librbd::mirror::snapshot::CreateNonPrimaryRequest<librbd::MockTestImageCtx>;
+
+namespace librbd {
+namespace mirror {
+namespace snapshot {
+
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::InSequence;
+using ::testing::Invoke;
+using ::testing::Return;
+using ::testing::StrEq;
+using ::testing::WithArg;
+
+class TestMockMirrorSnapshotCreateNonPrimaryRequest : public TestMockFixture {
+public:
+  typedef CreateNonPrimaryRequest<MockTestImageCtx> MockCreateNonPrimaryRequest;
+  typedef WriteImageStateRequest<MockTestImageCtx> MockWriteImageStateRequest;
+  typedef util::Mock MockUtils;
+
+  void expect_clone_md_ctx(MockTestImageCtx &mock_image_ctx) {
+    EXPECT_CALL(get_mock_io_ctx(mock_image_ctx.md_ctx), clone())
+      .WillOnce(Invoke([&mock_image_ctx]() {
+                         get_mock_io_ctx(mock_image_ctx.md_ctx).get();
+                         return &get_mock_io_ctx(mock_image_ctx.md_ctx);
+                       }));
+  }
+
+  void expect_refresh_image(MockTestImageCtx &mock_image_ctx,
+                            bool refresh_required, int r) {
+    EXPECT_CALL(*mock_image_ctx.state, is_refresh_required())
+      .WillOnce(Return(refresh_required));
+    if (refresh_required) {
+      EXPECT_CALL(*mock_image_ctx.state, refresh(_))
+        .WillOnce(CompleteContext(r, mock_image_ctx.image_ctx->op_work_queue));
+    }
+  }
+
+  void expect_get_mirror_image(MockTestImageCtx &mock_image_ctx,
+                               const cls::rbd::MirrorImage &mirror_image,
+                               int r) {
+    using ceph::encode;
+    bufferlist bl;
+    encode(mirror_image, bl);
+
+    EXPECT_CALL(get_mock_io_ctx(mock_image_ctx.md_ctx),
+                exec(RBD_MIRRORING, _, StrEq("rbd"), StrEq("mirror_image_get"),
+                     _, _, _, _))
+      .WillOnce(DoAll(WithArg<5>(CopyInBufferlist(bl)),
+                      Return(r)));
+  }
+
+  void expect_can_create_non_primary_snapshot(MockUtils &mock_utils,
+                                              bool result) {
+    EXPECT_CALL(mock_utils, can_create_non_primary_snapshot(_))
+      .WillOnce(Return(result));
+  }
+
+  void expect_get_mirror_peers(MockTestImageCtx &mock_image_ctx,
+                               const std::vector<cls::rbd::MirrorPeer> &peers,
+                               int r) {
+    using ceph::encode;
+    bufferlist bl;
+    encode(peers, bl);
+
+    EXPECT_CALL(get_mock_io_ctx(mock_image_ctx.md_ctx),
+                exec(RBD_MIRRORING, _, StrEq("rbd"), StrEq("mirror_peer_list"),
+                     _, _, _, _))
+      .WillOnce(DoAll(WithArg<5>(CopyInBufferlist(bl)),
+                      Return(r)));
+  }
+
+  void expect_create_snapshot(MockTestImageCtx &mock_image_ctx, int r) {
+    EXPECT_CALL(*mock_image_ctx.operations, snap_create(_, _, _, _, _))
+      .WillOnce(WithArg<4>(CompleteContext(
+                             r, mock_image_ctx.image_ctx->op_work_queue)));
+  }
+
+  void expect_write_image_state(
+      MockTestImageCtx &mock_image_ctx,
+      MockWriteImageStateRequest &mock_write_image_state_request, int r) {
+    EXPECT_CALL(mock_image_ctx, get_snap_id(_, _))
+      .WillOnce(Return(123));
+    EXPECT_CALL(mock_write_image_state_request, send())
+      .WillOnce(Invoke([&mock_image_ctx, &mock_write_image_state_request, r]() {
+                         mock_image_ctx.image_ctx->op_work_queue->queue(
+                           mock_write_image_state_request.on_finish, r);
+                       }));
+  }
+};
+
+TEST_F(TestMockMirrorSnapshotCreateNonPrimaryRequest, Success) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_refresh_image(mock_image_ctx, true, 0);
+  expect_get_mirror_image(
+    mock_image_ctx, {cls::rbd::MIRROR_IMAGE_MODE_SNAPSHOT, "gid",
+                     cls::rbd::MIRROR_IMAGE_STATE_ENABLED}, 0);
+  MockUtils mock_utils;
+  expect_can_create_non_primary_snapshot(mock_utils, true);
+  expect_create_snapshot(mock_image_ctx, 0);
+  MockWriteImageStateRequest mock_write_image_state_request;
+  expect_write_image_state(mock_image_ctx, mock_write_image_state_request, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockCreateNonPrimaryRequest(&mock_image_ctx, false,
+                                             "mirror_uuid", 123, {{1, 2}}, {},
+                                             nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreateNonPrimaryRequest, SuccessDemoted) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_clone_md_ctx(mock_image_ctx);
+  expect_refresh_image(mock_image_ctx, true, 0);
+  expect_get_mirror_image(
+    mock_image_ctx, {cls::rbd::MIRROR_IMAGE_MODE_SNAPSHOT, "gid",
+                     cls::rbd::MIRROR_IMAGE_STATE_ENABLED}, 0);
+  MockUtils mock_utils;
+  expect_can_create_non_primary_snapshot(mock_utils, true);
+  expect_get_mirror_peers(mock_image_ctx,
+                          {{"uuid", cls::rbd::MIRROR_PEER_DIRECTION_TX, "ceph",
+                            "mirror", "mirror uuid"}}, 0);
+  expect_create_snapshot(mock_image_ctx, 0);
+  MockWriteImageStateRequest mock_write_image_state_request;
+  expect_write_image_state(mock_image_ctx, mock_write_image_state_request, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockCreateNonPrimaryRequest(&mock_image_ctx, true,
+                                             "mirror_uuid", 123, {{1, 2}}, {},
+                                             nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreateNonPrimaryRequest, RefreshError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_refresh_image(mock_image_ctx, true, -EINVAL);
+
+  C_SaferCond ctx;
+  auto req = new MockCreateNonPrimaryRequest(&mock_image_ctx, false,
+                                             "mirror_uuid", 123, {{1, 2}}, {},
+                                             nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreateNonPrimaryRequest, GetMirrorImageError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_refresh_image(mock_image_ctx, false, 0);
+  expect_get_mirror_image(
+    mock_image_ctx, {cls::rbd::MIRROR_IMAGE_MODE_SNAPSHOT, "gid",
+                     cls::rbd::MIRROR_IMAGE_STATE_ENABLED}, -EINVAL);
+
+  C_SaferCond ctx;
+  auto req = new MockCreateNonPrimaryRequest(&mock_image_ctx, false,
+                                             "mirror_uuid", 123, {{1, 2}}, {},
+                                             nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreateNonPrimaryRequest, CanNotError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_refresh_image(mock_image_ctx, false, 0);
+  expect_get_mirror_image(
+    mock_image_ctx, {cls::rbd::MIRROR_IMAGE_MODE_SNAPSHOT, "gid",
+                     cls::rbd::MIRROR_IMAGE_STATE_ENABLED}, 0);
+  MockUtils mock_utils;
+  expect_can_create_non_primary_snapshot(mock_utils, false);
+
+  C_SaferCond ctx;
+  auto req = new MockCreateNonPrimaryRequest(&mock_image_ctx, false,
+                                             "mirror_uuid", 123, {{1, 2}}, {},
+                                             nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreateNonPrimaryRequest, GetMirrorPeersError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_clone_md_ctx(mock_image_ctx);
+  expect_refresh_image(mock_image_ctx, true, 0);
+  expect_get_mirror_image(
+    mock_image_ctx, {cls::rbd::MIRROR_IMAGE_MODE_SNAPSHOT, "gid",
+                     cls::rbd::MIRROR_IMAGE_STATE_ENABLED}, 0);
+  MockUtils mock_utils;
+  expect_can_create_non_primary_snapshot(mock_utils, true);
+  expect_get_mirror_peers(mock_image_ctx, {}, -EPERM);
+
+  C_SaferCond ctx;
+  auto req = new MockCreateNonPrimaryRequest(&mock_image_ctx, true,
+                                             "mirror_uuid", 123, {{1, 2}}, {},
+                                             nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(-EPERM, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreateNonPrimaryRequest, CreateSnapshotError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_refresh_image(mock_image_ctx, true, 0);
+  expect_get_mirror_image(
+    mock_image_ctx, {cls::rbd::MIRROR_IMAGE_MODE_SNAPSHOT, "gid",
+                     cls::rbd::MIRROR_IMAGE_STATE_ENABLED}, 0);
+  MockUtils mock_utils;
+  expect_can_create_non_primary_snapshot(mock_utils, true);
+  expect_create_snapshot(mock_image_ctx, -EINVAL);
+
+  C_SaferCond ctx;
+  auto req = new MockCreateNonPrimaryRequest(&mock_image_ctx, false,
+                                             "mirror_uuid", 123, {{1, 2}}, {},
+                                             nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreateNonPrimaryRequest, WriteImageStateError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_refresh_image(mock_image_ctx, true, 0);
+  expect_get_mirror_image(
+    mock_image_ctx, {cls::rbd::MIRROR_IMAGE_MODE_SNAPSHOT, "gid",
+                     cls::rbd::MIRROR_IMAGE_STATE_ENABLED}, 0);
+  MockUtils mock_utils;
+  expect_can_create_non_primary_snapshot(mock_utils, true);
+  expect_create_snapshot(mock_image_ctx, 0);
+  MockWriteImageStateRequest mock_write_image_state_request;
+  expect_write_image_state(mock_image_ctx, mock_write_image_state_request,
+                           -EINVAL);
+
+  C_SaferCond ctx;
+  auto req = new MockCreateNonPrimaryRequest(&mock_image_ctx, false,
+                                             "mirror_uuid", 123, {{1, 2}}, {},
+                                             nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+} // namespace snapshot
+} // namespace mirror
+} // namespace librbd
diff --git a/src/test/librbd/mirror/snapshot/test_mock_CreatePrimaryRequest.cc b/src/test/librbd/mirror/snapshot/test_mock_CreatePrimaryRequest.cc
new file mode 100644
index 000000000..bf0363486
--- /dev/null
+++ b/src/test/librbd/mirror/snapshot/test_mock_CreatePrimaryRequest.cc
@@ -0,0 +1,404 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "include/stringify.h"
+#include "test/librbd/test_mock_fixture.h"
+#include "test/librbd/test_support.h"
+#include "test/librbd/mock/MockImageCtx.h"
+#include "test/librbd/mock/MockOperations.h"
+#include "test/librados_test_stub/MockTestMemIoCtxImpl.h"
+#include "test/librados_test_stub/MockTestMemRadosClient.h"
+#include "librbd/mirror/snapshot/CreatePrimaryRequest.h"
+#include "librbd/mirror/snapshot/UnlinkPeerRequest.h"
+#include "librbd/mirror/snapshot/Utils.h"
+
+namespace librbd {
+
+namespace {
+
+struct MockTestImageCtx : public MockImageCtx {
+  explicit MockTestImageCtx(librbd::ImageCtx& image_ctx) : MockImageCtx(image_ctx) {
+  }
+};
+
+} // anonymous namespace
+
+namespace mirror {
+namespace snapshot {
+namespace util {
+
+namespace {
+
+struct Mock {
+  static Mock* s_instance;
+
+  Mock() {
+    s_instance = this;
+  }
+
+  MOCK_METHOD4(can_create_primary_snapshot,
+               bool(librbd::MockTestImageCtx *, bool, bool, uint64_t *));
+};
+
+Mock *Mock::s_instance = nullptr;
+
+} // anonymous namespace
+
+template<> bool can_create_primary_snapshot(librbd::MockTestImageCtx *image_ctx,
+                                            bool demoted, bool force,
+                                            bool* requires_orphan,
+                                            uint64_t *rollback_snap_id) {
+  return Mock::s_instance->can_create_primary_snapshot(image_ctx, demoted,
+                                                       force, rollback_snap_id);
+}
+
+} // namespace util
+
+template <>
+struct UnlinkPeerRequest<MockTestImageCtx> {
+  uint64_t snap_id = CEPH_NOSNAP;
+  std::string mirror_peer_uuid;
+  Context* on_finish = nullptr;
+  static UnlinkPeerRequest* s_instance;
+  static UnlinkPeerRequest *create(MockTestImageCtx *image_ctx,
+                                   uint64_t snap_id,
+                                   const std::string &mirror_peer_uuid,
+                                   Context *on_finish) {
+    ceph_assert(s_instance != nullptr);
+    s_instance->snap_id = snap_id;
+    s_instance->mirror_peer_uuid = mirror_peer_uuid;
+    s_instance->on_finish = on_finish;
+    return s_instance;
+  }
+
+  MOCK_METHOD0(send, void());
+
+  UnlinkPeerRequest() {
+    s_instance = this;
+  }
+};
+
+UnlinkPeerRequest<MockTestImageCtx>* UnlinkPeerRequest<MockTestImageCtx>::s_instance = nullptr;
+
+} // namespace snapshot
+} // namespace mirror
+} // namespace librbd
+
+// template definitions
+#include "librbd/mirror/snapshot/CreatePrimaryRequest.cc"
+template class librbd::mirror::snapshot::CreatePrimaryRequest<librbd::MockTestImageCtx>;
+
+namespace librbd {
+namespace mirror {
+namespace snapshot {
+
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::InSequence;
+using ::testing::Invoke;
+using ::testing::Return;
+using ::testing::StrEq;
+using ::testing::WithArg;
+
+class TestMockMirrorSnapshotCreatePrimaryRequest : public TestMockFixture {
+public:
+  typedef CreatePrimaryRequest<MockTestImageCtx> MockCreatePrimaryRequest;
+  typedef UnlinkPeerRequest<MockTestImageCtx> MockUnlinkPeerRequest;
+  typedef util::Mock MockUtils;
+
+  uint64_t m_snap_seq = 0;
+
+  void snap_create(MockTestImageCtx &mock_image_ctx,
+                   const cls::rbd::SnapshotNamespace &ns,
+                   const std::string& snap_name) {
+    ASSERT_TRUE(mock_image_ctx.snap_info.insert(
+                  {m_snap_seq++,
+                   SnapInfo{snap_name, ns, 0, {}, 0, 0, {}}}).second);
+  }
+
+  void expect_clone_md_ctx(MockTestImageCtx &mock_image_ctx) {
+    EXPECT_CALL(get_mock_io_ctx(mock_image_ctx.md_ctx), clone())
+      .WillOnce(Invoke([&mock_image_ctx]() {
+                         get_mock_io_ctx(mock_image_ctx.md_ctx).get();
+                         return &get_mock_io_ctx(mock_image_ctx.md_ctx);
+                       }));
+  }
+
+  void expect_can_create_primary_snapshot(MockUtils &mock_utils, bool demoted,
+                                          bool force, bool result) {
+    EXPECT_CALL(mock_utils,
+                can_create_primary_snapshot(_, demoted, force, nullptr))
+      .WillOnce(Return(result));
+  }
+
+  void expect_get_mirror_peers(MockTestImageCtx &mock_image_ctx,
+                               const std::vector<cls::rbd::MirrorPeer> &peers,
+                               int r) {
+    using ceph::encode;
+    bufferlist bl;
+    encode(peers, bl);
+
+    EXPECT_CALL(get_mock_io_ctx(mock_image_ctx.md_ctx),
+                exec(RBD_MIRRORING, _, StrEq("rbd"), StrEq("mirror_peer_list"),
+                     _, _, _, _))
+      .WillOnce(DoAll(WithArg<5>(CopyInBufferlist(bl)),
+                      Return(r)));
+  }
+
+  void expect_create_snapshot(MockTestImageCtx &mock_image_ctx, int r) {
+    EXPECT_CALL(*mock_image_ctx.operations, snap_create(_, _, _, _, _))
+      .WillOnce(DoAll(
+                  Invoke([this, &mock_image_ctx, r](
+                             const cls::rbd::SnapshotNamespace &ns,
+                             const std::string& snap_name,
+                             uint64_t flags,
+                             ProgressContext &prog_ctx,
+                             Context *on_finish) {
+                           if (r != 0) {
+                             return;
+                           }
+                           snap_create(mock_image_ctx, ns, snap_name);
+                         }),
+                  WithArg<4>(CompleteContext(
+                               r, mock_image_ctx.image_ctx->op_work_queue))
+                  ));
+  }
+
+  void expect_unlink_peer(MockTestImageCtx &mock_image_ctx,
+                          MockUnlinkPeerRequest &mock_unlink_peer_request,
+                          uint64_t snap_id, const std::string &peer_uuid,
+                          bool is_linked, int r) {
+    EXPECT_CALL(mock_unlink_peer_request, send())
+      .WillOnce(Invoke([&mock_image_ctx, &mock_unlink_peer_request,
+                        snap_id, peer_uuid, is_linked, r]() {
+                         ASSERT_EQ(mock_unlink_peer_request.mirror_peer_uuid,
+                                   peer_uuid);
+                         ASSERT_EQ(mock_unlink_peer_request.snap_id, snap_id);
+                         if (r == 0) {
+                           auto it = mock_image_ctx.snap_info.find(snap_id);
+                           ASSERT_NE(it, mock_image_ctx.snap_info.end());
+                           auto info =
+                             boost::get<cls::rbd::MirrorSnapshotNamespace>(
+                               &it->second.snap_namespace);
+                           ASSERT_NE(nullptr, info);
+                           ASSERT_EQ(is_linked, info->mirror_peer_uuids.erase(
+                                     peer_uuid));
+                           if (info->mirror_peer_uuids.empty()) {
+                             mock_image_ctx.snap_info.erase(it);
+                           }
+                         }
+                         mock_image_ctx.image_ctx->op_work_queue->queue(
+                           mock_unlink_peer_request.on_finish, r);
+                       }));
+  }
+};
+
+TEST_F(TestMockMirrorSnapshotCreatePrimaryRequest, Success) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_clone_md_ctx(mock_image_ctx);
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, false, false, true);
+  expect_get_mirror_peers(mock_image_ctx,
+                          {{"uuid", cls::rbd::MIRROR_PEER_DIRECTION_TX, "ceph",
+                            "mirror", "mirror uuid"}}, 0);
+  expect_create_snapshot(mock_image_ctx, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockCreatePrimaryRequest(&mock_image_ctx, "gid", CEPH_NOSNAP,
+                                          0U, 0U, nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreatePrimaryRequest, CanNotError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_clone_md_ctx(mock_image_ctx);
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, false, false, false);
+
+  C_SaferCond ctx;
+  auto req = new MockCreatePrimaryRequest(&mock_image_ctx, "gid", CEPH_NOSNAP,
+                                          0U, 0U, nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreatePrimaryRequest, GetMirrorPeersError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_clone_md_ctx(mock_image_ctx);
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, false, false, true);
+  expect_get_mirror_peers(mock_image_ctx,
+                          {{"uuid", cls::rbd::MIRROR_PEER_DIRECTION_TX, "ceph",
+                            "mirror", "mirror uuid"}}, -EINVAL);
+
+  C_SaferCond ctx;
+  auto req = new MockCreatePrimaryRequest(&mock_image_ctx, "gid", CEPH_NOSNAP,
+                                          0U, 0U, nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreatePrimaryRequest, CreateSnapshotError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_clone_md_ctx(mock_image_ctx);
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, false, false, true);
+  expect_get_mirror_peers(mock_image_ctx,
+                          {{"uuid", cls::rbd::MIRROR_PEER_DIRECTION_TX, "ceph",
+                            "mirror", "mirror uuid"}}, 0);
+  expect_create_snapshot(mock_image_ctx, -EINVAL);
+
+  C_SaferCond ctx;
+  auto req = new MockCreatePrimaryRequest(&mock_image_ctx, "gid", CEPH_NOSNAP,
+                                          0U, 0U, nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreatePrimaryRequest, SuccessUnlinkPeer) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+  ictx->config.set_val("rbd_mirroring_max_mirroring_snapshots", "3");
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  for (int i = 0; i < 3; i++) {
+    cls::rbd::MirrorSnapshotNamespace ns{
+      cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"uuid"}, "", CEPH_NOSNAP};
+    snap_create(mock_image_ctx, ns, "mirror_snap");
+  }
+
+  InSequence seq;
+
+  expect_clone_md_ctx(mock_image_ctx);
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, false, false, true);
+  expect_get_mirror_peers(mock_image_ctx,
+                          {{"uuid", cls::rbd::MIRROR_PEER_DIRECTION_TX, "ceph",
+                            "mirror", "mirror uuid"}}, 0);
+  expect_create_snapshot(mock_image_ctx, 0);
+  MockUnlinkPeerRequest mock_unlink_peer_request;
+  auto it = mock_image_ctx.snap_info.rbegin();
+  auto snap_id = it->first;
+  expect_unlink_peer(mock_image_ctx, mock_unlink_peer_request, snap_id, "uuid",
+                     true, 0);
+  C_SaferCond ctx;
+  auto req = new MockCreatePrimaryRequest(&mock_image_ctx, "gid", CEPH_NOSNAP,
+                                          0U, 0U, nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreatePrimaryRequest, SuccessUnlinkNoPeer) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+  ictx->config.set_val("rbd_mirroring_max_mirroring_snapshots", "3");
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  cls::rbd::MirrorSnapshotNamespace ns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {}, "", CEPH_NOSNAP};
+  snap_create(mock_image_ctx, ns, "mirror_snap");
+
+  InSequence seq;
+
+  expect_clone_md_ctx(mock_image_ctx);
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, false, false, true);
+  expect_get_mirror_peers(mock_image_ctx,
+                          {{"uuid", cls::rbd::MIRROR_PEER_DIRECTION_TX, "ceph",
+                            "mirror", "mirror uuid"}}, 0);
+  expect_create_snapshot(mock_image_ctx, 0);
+  MockUnlinkPeerRequest mock_unlink_peer_request;
+  auto it = mock_image_ctx.snap_info.rbegin();
+  auto snap_id = it->first;
+  std::list<string> peer_uuids = {"uuid"};
+  expect_unlink_peer(mock_image_ctx, mock_unlink_peer_request, snap_id, "uuid",
+                     false, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockCreatePrimaryRequest(&mock_image_ctx, "gid", CEPH_NOSNAP,
+                                          0U, 0U, nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotCreatePrimaryRequest, SuccessUnlinkMultiplePeers) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+  ictx->config.set_val("rbd_mirroring_max_mirroring_snapshots", "3");
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  for (int i = 0; i < 3; i++) {
+    cls::rbd::MirrorSnapshotNamespace ns{
+      cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"uuid1", "uuid2"}, "",
+      CEPH_NOSNAP};
+    snap_create(mock_image_ctx, ns, "mirror_snap");
+  }
+
+  InSequence seq;
+
+  expect_clone_md_ctx(mock_image_ctx);
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, false, false, true);
+  expect_get_mirror_peers(mock_image_ctx,
+                          {{"uuid1", cls::rbd::MIRROR_PEER_DIRECTION_TX, "ceph",
+                            "mirror", "mirror uuid"},
+                           {"uuid2", cls::rbd::MIRROR_PEER_DIRECTION_TX, "ceph",
+                            "mirror", "mirror uuid"}}, 0);
+  expect_create_snapshot(mock_image_ctx, 0);
+  MockUnlinkPeerRequest mock_unlink_peer_request;
+  auto it = mock_image_ctx.snap_info.rbegin();
+  auto snap_id = it->first;
+  expect_unlink_peer(mock_image_ctx, mock_unlink_peer_request, snap_id, "uuid1",
+                     true, 0);
+  expect_unlink_peer(mock_image_ctx, mock_unlink_peer_request, snap_id, "uuid2",
+                     true, 0);
+  C_SaferCond ctx;
+  auto req = new MockCreatePrimaryRequest(&mock_image_ctx, "gid", CEPH_NOSNAP,
+                                          0U, 0U, nullptr, &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+} // namespace snapshot
+} // namespace mirror
+} // namespace librbd
+
diff --git a/src/test/librbd/mirror/snapshot/test_mock_ImageMeta.cc b/src/test/librbd/mirror/snapshot/test_mock_ImageMeta.cc
new file mode 100644
index 000000000..70a5eaeb0
--- /dev/null
+++ b/src/test/librbd/mirror/snapshot/test_mock_ImageMeta.cc
@@ -0,0 +1,159 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "test/librbd/test_mock_fixture.h"
+#include "test/librbd/test_support.h"
+#include "test/librbd/mock/MockImageCtx.h"
+#include "test/librados_test_stub/MockTestMemIoCtxImpl.h"
+#include "librbd/ImageState.h"
+#include "librbd/mirror/snapshot/ImageMeta.h"
+#include "librbd/mirror/snapshot/Utils.h"
+
+namespace librbd {
+namespace {
+
+struct MockTestImageCtx : public MockImageCtx {
+  MockTestImageCtx(librbd::ImageCtx& image_ctx) : MockImageCtx(image_ctx) {
+  }
+};
+
+} // anonymous namespace
+} // namespace librbd
+
+#include "librbd/mirror/snapshot/ImageMeta.cc"
+
+namespace librbd {
+namespace mirror {
+namespace snapshot {
+
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::InSequence;
+using ::testing::Invoke;
+using ::testing::Return;
+using ::testing::StrEq;
+using ::testing::WithArg;
+
+class TestMockMirrorSnapshotImageMeta : public TestMockFixture {
+public:
+  typedef ImageMeta<MockTestImageCtx> MockImageMeta;
+
+  void expect_metadata_get(MockTestImageCtx& mock_image_ctx,
+                           const std::string& mirror_uuid,
+                           const std::string& value, int r) {
+    bufferlist in_bl;
+    ceph::encode(util::get_image_meta_key(mirror_uuid), in_bl);
+
+    bufferlist out_bl;
+    ceph::encode(value, out_bl);
+
+    EXPECT_CALL(get_mock_io_ctx(mock_image_ctx.md_ctx),
+                exec(mock_image_ctx.header_oid, _, StrEq("rbd"),
+                     StrEq("metadata_get"), ContentsEqual(in_bl), _, _, _))
+      .WillOnce(DoAll(WithArg<5>(CopyInBufferlist(out_bl)),
+                      Return(r)));
+  }
+
+  void expect_metadata_set(MockTestImageCtx& mock_image_ctx,
+                           const std::string& mirror_uuid,
+                           const std::string& value, int r) {
+    bufferlist value_bl;
+    value_bl.append(value);
+
+    bufferlist in_bl;
+    ceph::encode(
+      std::map<std::string, bufferlist>{
+        {util::get_image_meta_key(mirror_uuid), value_bl}},
+      in_bl);
+
+    EXPECT_CALL(get_mock_io_ctx(mock_image_ctx.md_ctx),
+                exec(mock_image_ctx.header_oid, _, StrEq("rbd"),
+                     StrEq("metadata_set"), ContentsEqual(in_bl), _, _, _))
+      .WillOnce(Return(r));
+  }
+};
+
+TEST_F(TestMockMirrorSnapshotImageMeta, Load) {
+  librbd::ImageCtx* image_ctx;
+  ASSERT_EQ(0, open_image(m_image_name, &image_ctx));
+  MockTestImageCtx mock_image_ctx(*image_ctx);
+
+  InSequence seq;
+  expect_metadata_get(mock_image_ctx, "mirror uuid",
+                      "{\"resync_requested\": true}", 0);
+
+  MockImageMeta mock_image_meta(&mock_image_ctx, "mirror uuid");
+  C_SaferCond ctx;
+  mock_image_meta.load(&ctx);
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotImageMeta, LoadError) {
+  librbd::ImageCtx* image_ctx;
+  ASSERT_EQ(0, open_image(m_image_name, &image_ctx));
+  MockTestImageCtx mock_image_ctx(*image_ctx);
+
+  InSequence seq;
+  expect_metadata_get(mock_image_ctx, "mirror uuid",
+                      "{\"resync_requested\": true}", -EINVAL);
+
+  MockImageMeta mock_image_meta(&mock_image_ctx, "mirror uuid");
+  C_SaferCond ctx;
+  mock_image_meta.load(&ctx);
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotImageMeta, LoadCorrupt) {
+  librbd::ImageCtx* image_ctx;
+  ASSERT_EQ(0, open_image(m_image_name, &image_ctx));
+  MockTestImageCtx mock_image_ctx(*image_ctx);
+
+  InSequence seq;
+  expect_metadata_get(mock_image_ctx, "mirror uuid",
+                      "\"resync_requested\": true}", 0);
+
+  MockImageMeta mock_image_meta(&mock_image_ctx, "mirror uuid");
+  C_SaferCond ctx;
+  mock_image_meta.load(&ctx);
+  ASSERT_EQ(-EBADMSG, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotImageMeta, Save) {
+  librbd::ImageCtx* image_ctx;
+  ASSERT_EQ(0, open_image(m_image_name, &image_ctx));
+  MockTestImageCtx mock_image_ctx(*image_ctx);
+
+  InSequence seq;
+  expect_metadata_set(mock_image_ctx, "mirror uuid",
+                      "{\"resync_requested\": true}", 0);
+
+  MockImageMeta mock_image_meta(&mock_image_ctx, "mirror uuid");
+  mock_image_meta.resync_requested = true;
+
+  C_SaferCond ctx;
+  mock_image_meta.save(&ctx);
+  ASSERT_EQ(0, ctx.wait());
+
+  // should have sent image-update notification
+  ASSERT_TRUE(image_ctx->state->is_refresh_required());
+}
+
+TEST_F(TestMockMirrorSnapshotImageMeta, SaveError) {
+  librbd::ImageCtx* image_ctx;
+  ASSERT_EQ(0, open_image(m_image_name, &image_ctx));
+  MockTestImageCtx mock_image_ctx(*image_ctx);
+
+  InSequence seq;
+  expect_metadata_set(mock_image_ctx, "mirror uuid",
+                      "{\"resync_requested\": false}", -EINVAL);
+
+  MockImageMeta mock_image_meta(&mock_image_ctx, "mirror uuid");
+
+  C_SaferCond ctx;
+  mock_image_meta.save(&ctx);
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+} // namespace snapshot
+} // namespace mirror
+} // namespace librbd
diff --git a/src/test/librbd/mirror/snapshot/test_mock_PromoteRequest.cc b/src/test/librbd/mirror/snapshot/test_mock_PromoteRequest.cc
new file mode 100644
index 000000000..af9c34933
--- /dev/null
+++ b/src/test/librbd/mirror/snapshot/test_mock_PromoteRequest.cc
@@ -0,0 +1,389 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "include/stringify.h"
+#include "test/librbd/test_mock_fixture.h"
+#include "test/librbd/test_support.h"
+#include "test/librbd/mock/MockImageCtx.h"
+#include "test/librbd/mock/MockOperations.h"
+#include "test/librados_test_stub/MockTestMemIoCtxImpl.h"
+#include "test/librados_test_stub/MockTestMemRadosClient.h"
+#include "librbd/image/ListWatchersRequest.h"
+#include "librbd/mirror/snapshot/CreateNonPrimaryRequest.h"
+#include "librbd/mirror/snapshot/CreatePrimaryRequest.h"
+#include "librbd/mirror/snapshot/PromoteRequest.h"
+#include "librbd/mirror/snapshot/Utils.h"
+
+namespace librbd {
+
+namespace {
+
+struct MockTestImageCtx : public MockImageCtx {
+  explicit MockTestImageCtx(librbd::ImageCtx& image_ctx) : MockImageCtx(image_ctx) {
+  }
+};
+
+} // anonymous namespace
+
+namespace image {
+
+template <>
+struct ListWatchersRequest<MockTestImageCtx> {
+  std::list<obj_watch_t> *watchers;
+  Context* on_finish = nullptr;
+  static ListWatchersRequest* s_instance;
+  static ListWatchersRequest *create(MockTestImageCtx &image_ctx, int flags,
+                                     std::list<obj_watch_t> *watchers,
+                                     Context *on_finish) {
+    ceph_assert(s_instance != nullptr);
+    s_instance->watchers = watchers;
+    s_instance->on_finish = on_finish;
+    return s_instance;
+  }
+
+  MOCK_METHOD0(send, void());
+
+  ListWatchersRequest() {
+    s_instance = this;
+  }
+};
+
+ListWatchersRequest<MockTestImageCtx>* ListWatchersRequest<MockTestImageCtx>::s_instance = nullptr;
+
+} // namespace image
+
+namespace mirror {
+namespace snapshot {
+namespace util {
+
+namespace {
+
+struct Mock {
+  static Mock* s_instance;
+
+  Mock() {
+    s_instance = this;
+  }
+
+  MOCK_METHOD5(can_create_primary_snapshot,
+               bool(librbd::MockTestImageCtx *, bool, bool, bool*, uint64_t *));
+};
+
+Mock *Mock::s_instance = nullptr;
+
+} // anonymous namespace
+
+template<> bool can_create_primary_snapshot(librbd::MockTestImageCtx *image_ctx,
+                                            bool demoted, bool force,
+                                            bool* requires_orphan,
+                                            uint64_t *rollback_snap_id) {
+  return Mock::s_instance->can_create_primary_snapshot(image_ctx, demoted,
+                                                       force, requires_orphan,
+                                                       rollback_snap_id);
+}
+
+} // namespace util
+
+template <>
+struct CreateNonPrimaryRequest<MockTestImageCtx> {
+  std::string primary_mirror_uuid;
+  uint64_t primary_snap_id = CEPH_NOSNAP;
+  Context* on_finish = nullptr;
+  static CreateNonPrimaryRequest* s_instance;
+  static CreateNonPrimaryRequest *create(MockTestImageCtx *image_ctx,
+                                         bool demoted,
+                                         const std::string &primary_mirror_uuid,
+                                         uint64_t primary_snap_id,
+                                         SnapSeqs snap_seqs,
+                                         const ImageState &image_state,
+                                         uint64_t *snap_id,
+                                         Context *on_finish) {
+    ceph_assert(s_instance != nullptr);
+    s_instance->primary_mirror_uuid = primary_mirror_uuid;
+    s_instance->primary_snap_id = primary_snap_id;
+    s_instance->on_finish = on_finish;
+    return s_instance;
+  }
+
+  MOCK_METHOD0(send, void());
+
+  CreateNonPrimaryRequest() {
+    s_instance = this;
+  }
+};
+
+CreateNonPrimaryRequest<MockTestImageCtx>* CreateNonPrimaryRequest<MockTestImageCtx>::s_instance = nullptr;
+
+template <>
+struct CreatePrimaryRequest<MockTestImageCtx> {
+  bool demoted = false;
+  bool force = false;
+  Context* on_finish = nullptr;
+  static CreatePrimaryRequest* s_instance;
+  static CreatePrimaryRequest *create(MockTestImageCtx *image_ctx,
+                                      const std::string& global_image_id,
+                                      uint64_t clean_since_snap_id,
+                                      uint64_t snap_create_flags,
+                                      uint32_t flags, uint64_t *snap_id,
+                                      Context *on_finish) {
+    ceph_assert(s_instance != nullptr);
+    s_instance->demoted = ((flags & CREATE_PRIMARY_FLAG_DEMOTED) != 0);
+    s_instance->force = ((flags & CREATE_PRIMARY_FLAG_FORCE) != 0);
+    s_instance->on_finish = on_finish;
+    return s_instance;
+  }
+
+  MOCK_METHOD0(send, void());
+
+  CreatePrimaryRequest() {
+    s_instance = this;
+  }
+};
+
+CreatePrimaryRequest<MockTestImageCtx>* CreatePrimaryRequest<MockTestImageCtx>::s_instance = nullptr;
+
+} // namespace snapshot
+} // namespace mirror
+} // namespace librbd
+
+// template definitions
+#include "librbd/mirror/snapshot/PromoteRequest.cc"
+template class librbd::mirror::snapshot::PromoteRequest<librbd::MockTestImageCtx>;
+
+namespace librbd {
+namespace mirror {
+namespace snapshot {
+
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::InSequence;
+using ::testing::Invoke;
+using ::testing::Return;
+using ::testing::StrEq;
+using ::testing::WithArg;
+using ::testing::WithArgs;
+
+class TestMockMirrorSnapshotPromoteRequest : public TestMockFixture {
+public:
+  typedef librbd::image::ListWatchersRequest<MockTestImageCtx> MockListWatchersRequest;
+  typedef PromoteRequest<MockTestImageCtx> MockPromoteRequest;
+  typedef CreateNonPrimaryRequest<MockTestImageCtx> MockCreateNonPrimaryRequest;
+  typedef CreatePrimaryRequest<MockTestImageCtx> MockCreatePrimaryRequest;
+  typedef util::Mock MockUtils;
+
+  void expect_can_create_primary_snapshot(MockUtils &mock_utils, bool force,
+                                          bool requires_orphan,
+                                          uint64_t rollback_snap_id,
+                                          bool result) {
+    EXPECT_CALL(mock_utils,
+                can_create_primary_snapshot(_, false, force, _, _))
+      .WillOnce(DoAll(
+                  WithArgs<3,4 >(Invoke(
+                    [requires_orphan, rollback_snap_id]
+                    (bool* orphan, uint64_t *snap_id) {
+                      *orphan = requires_orphan;
+                      *snap_id = rollback_snap_id;
+                    })),
+                  Return(result)));
+  }
+
+  void expect_create_orphan_snapshot(
+      MockTestImageCtx &mock_image_ctx,
+      MockCreateNonPrimaryRequest &mock_create_non_primary_request, int r) {
+    EXPECT_CALL(mock_create_non_primary_request, send())
+      .WillOnce(
+        Invoke([&mock_image_ctx, &mock_create_non_primary_request, r]() {
+                 mock_image_ctx.image_ctx->op_work_queue->queue(
+                   mock_create_non_primary_request.on_finish, r);
+               }));
+  }
+
+  void expect_list_watchers(
+      MockTestImageCtx &mock_image_ctx,
+      MockListWatchersRequest &mock_list_watchers_request,
+      const std::list<obj_watch_t> &watchers, int r) {
+    EXPECT_CALL(mock_list_watchers_request, send())
+      .WillOnce(
+        Invoke([&mock_image_ctx, &mock_list_watchers_request, watchers, r]() {
+                 *mock_list_watchers_request.watchers = watchers;
+                 mock_image_ctx.image_ctx->op_work_queue->queue(
+                   mock_list_watchers_request.on_finish, r);
+               }));
+  }
+
+  void expect_acquire_lock(MockTestImageCtx &mock_image_ctx, int r) {
+    if (mock_image_ctx.exclusive_lock == nullptr) {
+      return;
+    }
+    EXPECT_CALL(*mock_image_ctx.exclusive_lock, is_lock_owner())
+      .WillOnce(Return(false));
+    EXPECT_CALL(*mock_image_ctx.exclusive_lock, block_requests(_));
+    EXPECT_CALL(*mock_image_ctx.exclusive_lock, acquire_lock(_))
+      .WillOnce(CompleteContext(r, mock_image_ctx.image_ctx->op_work_queue));
+    if (r == 0) {
+      EXPECT_CALL(*mock_image_ctx.exclusive_lock, is_lock_owner())
+        .WillOnce(Return(true));
+    }
+  }
+
+  void expect_get_snap_info(MockTestImageCtx &mock_image_ctx,
+                            uint64_t snap_id, const SnapInfo* snap_info) {
+    EXPECT_CALL(mock_image_ctx, get_snap_info(snap_id))
+      .WillOnce(Return(snap_info));
+  }
+
+  void expect_rollback(MockTestImageCtx &mock_image_ctx, uint64_t snap_id,
+                       const SnapInfo* snap_info, int r) {
+    expect_get_snap_info(mock_image_ctx, snap_id, snap_info);
+    EXPECT_CALL(*mock_image_ctx.operations,
+                execute_snap_rollback(snap_info->snap_namespace,
+                                      snap_info->name, _, _))
+      .WillOnce(WithArg<3>(CompleteContext(
+                             r, mock_image_ctx.image_ctx->op_work_queue)));
+  }
+
+  void expect_create_promote_snapshot(
+      MockTestImageCtx &mock_image_ctx,
+      MockCreatePrimaryRequest &mock_create_primary_request, int r) {
+    EXPECT_CALL(mock_create_primary_request, send())
+      .WillOnce(
+        Invoke([&mock_image_ctx, &mock_create_primary_request, r]() {
+                 mock_image_ctx.image_ctx->op_work_queue->queue(
+                   mock_create_primary_request.on_finish, r);
+               }));
+  }
+
+  void expect_release_lock(MockTestImageCtx &mock_image_ctx, int r) {
+    if (mock_image_ctx.exclusive_lock == nullptr) {
+      return;
+    }
+    EXPECT_CALL(*mock_image_ctx.exclusive_lock, unblock_requests());
+    EXPECT_CALL(*mock_image_ctx.exclusive_lock, release_lock(_))
+      .WillOnce(CompleteContext(r, mock_image_ctx.image_ctx->op_work_queue));
+  }
+};
+
+TEST_F(TestMockMirrorSnapshotPromoteRequest, Success) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, true, false, CEPH_NOSNAP,
+                                     true);
+  MockCreatePrimaryRequest mock_create_primary_request;
+  expect_create_promote_snapshot(mock_image_ctx, mock_create_primary_request,
+                                 0);
+  C_SaferCond ctx;
+  auto req = new MockPromoteRequest(&mock_image_ctx, "gid", &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotPromoteRequest, SuccessForce) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  expect_op_work_queue(mock_image_ctx);
+
+  MockExclusiveLock mock_exclusive_lock;
+  if (ictx->test_features(RBD_FEATURE_EXCLUSIVE_LOCK)) {
+    mock_image_ctx.exclusive_lock = &mock_exclusive_lock;
+  }
+
+  InSequence seq;
+
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, true, true, CEPH_NOSNAP, true);
+  MockCreateNonPrimaryRequest mock_create_non_primary_request;
+  expect_create_orphan_snapshot(mock_image_ctx, mock_create_non_primary_request,
+                                0);
+  MockListWatchersRequest mock_list_watchers_request;
+  expect_list_watchers(mock_image_ctx, mock_list_watchers_request, {}, 0);
+  expect_acquire_lock(mock_image_ctx, 0);
+
+  SnapInfo snap_info = {"snap", cls::rbd::MirrorSnapshotNamespace{}, 0,
+                        {}, 0, 0, {}};
+  MockCreatePrimaryRequest mock_create_primary_request;
+  expect_create_promote_snapshot(mock_image_ctx, mock_create_primary_request,
+                                 0);
+  expect_release_lock(mock_image_ctx, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockPromoteRequest(&mock_image_ctx, "gid", &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotPromoteRequest, SuccessRollback) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  expect_op_work_queue(mock_image_ctx);
+
+  MockExclusiveLock mock_exclusive_lock;
+  if (ictx->test_features(RBD_FEATURE_EXCLUSIVE_LOCK)) {
+    mock_image_ctx.exclusive_lock = &mock_exclusive_lock;
+  }
+
+  InSequence seq;
+
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, true, false, 123, true);
+  MockCreateNonPrimaryRequest mock_create_non_primary_request;
+  expect_create_orphan_snapshot(mock_image_ctx, mock_create_non_primary_request,
+                                0);
+  MockListWatchersRequest mock_list_watchers_request;
+  expect_list_watchers(mock_image_ctx, mock_list_watchers_request, {}, 0);
+  expect_acquire_lock(mock_image_ctx, 0);
+
+  SnapInfo snap_info = {"snap", cls::rbd::MirrorSnapshotNamespace{}, 0,
+                        {}, 0, 0, {}};
+  expect_rollback(mock_image_ctx, 123, &snap_info, 0);
+  MockCreatePrimaryRequest mock_create_primary_request;
+  expect_create_promote_snapshot(mock_image_ctx, mock_create_primary_request,
+                                 0);
+  expect_release_lock(mock_image_ctx, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockPromoteRequest(&mock_image_ctx, "gid", &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotPromoteRequest, ErrorCannotRollback) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  expect_op_work_queue(mock_image_ctx);
+
+  InSequence seq;
+
+  MockUtils mock_utils;
+  expect_can_create_primary_snapshot(mock_utils, true, false, CEPH_NOSNAP,
+                                     false);
+
+  C_SaferCond ctx;
+  auto req = new MockPromoteRequest(&mock_image_ctx, "gid", &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+} // namespace snapshot
+} // namespace mirror
+} // namespace librbd
+
diff --git a/src/test/librbd/mirror/snapshot/test_mock_UnlinkPeerRequest.cc b/src/test/librbd/mirror/snapshot/test_mock_UnlinkPeerRequest.cc
new file mode 100644
index 000000000..456b6ccdc
--- /dev/null
+++ b/src/test/librbd/mirror/snapshot/test_mock_UnlinkPeerRequest.cc
@@ -0,0 +1,385 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "test/librbd/test_mock_fixture.h"
+#include "test/librbd/test_support.h"
+#include "test/librbd/mock/MockImageCtx.h"
+#include "test/librbd/mock/MockOperations.h"
+#include "test/librados_test_stub/MockTestMemIoCtxImpl.h"
+#include "test/librados_test_stub/MockTestMemRadosClient.h"
+#include "librbd/mirror/snapshot/UnlinkPeerRequest.h"
+
+namespace librbd {
+
+namespace {
+
+struct MockTestImageCtx : public MockImageCtx {
+  explicit MockTestImageCtx(librbd::ImageCtx& image_ctx) : MockImageCtx(image_ctx) {
+  }
+};
+
+} // anonymous namespace
+} // namespace librbd
+
+// template definitions
+#include "librbd/mirror/snapshot/UnlinkPeerRequest.cc"
+template class librbd::mirror::snapshot::UnlinkPeerRequest<librbd::MockTestImageCtx>;
+
+namespace librbd {
+namespace mirror {
+namespace snapshot {
+
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::InSequence;
+using ::testing::Invoke;
+using ::testing::Return;
+using ::testing::StrEq;
+
+class TestMockMirrorSnapshotUnlinkPeerRequest : public TestMockFixture {
+public:
+  typedef UnlinkPeerRequest<MockTestImageCtx> MockUnlinkPeerRequest;
+
+  uint64_t m_snap_seq = 0;
+
+  uint64_t snap_create(MockTestImageCtx &mock_image_ctx,
+                   const cls::rbd::SnapshotNamespace &ns,
+                   const std::string& snap_name) {
+    EXPECT_TRUE(mock_image_ctx.snap_info.insert(
+                  {++m_snap_seq,
+                   SnapInfo{snap_name, ns, 0, {}, 0, 0, {}}}).second);
+    return m_snap_seq;
+  }
+
+  void expect_get_snap_info(MockTestImageCtx &mock_image_ctx,
+                            librados::snap_t snap_id) {
+    EXPECT_CALL(mock_image_ctx, get_snap_info(snap_id))
+      .WillRepeatedly(Invoke([&mock_image_ctx](
+                                 librados::snap_t snap_id) -> librbd::SnapInfo * {
+                               auto it = mock_image_ctx.snap_info.find(snap_id);
+                               if (it == mock_image_ctx.snap_info.end()) {
+                                 return nullptr;
+                               }
+                               return &it->second;
+                             }));
+  }
+
+  void expect_is_refresh_required(MockTestImageCtx &mock_image_ctx,
+                                  bool refresh_required) {
+    EXPECT_CALL(*mock_image_ctx.state, is_refresh_required())
+      .WillOnce(Return(refresh_required));
+  }
+
+  void expect_refresh_image(MockTestImageCtx &mock_image_ctx, int r) {
+    EXPECT_CALL(*mock_image_ctx.state, refresh(_))
+      .WillOnce(CompleteContext(r, mock_image_ctx.image_ctx->op_work_queue));
+  }
+
+  void expect_unlink_peer(MockTestImageCtx &mock_image_ctx, uint64_t snap_id,
+                          const std::string &peer_uuid, int r) {
+    using ceph::encode;
+    bufferlist bl;
+    encode(snapid_t{snap_id}, bl);
+    encode(peer_uuid, bl);
+
+    EXPECT_CALL(get_mock_io_ctx(mock_image_ctx.md_ctx),
+                exec(mock_image_ctx.header_oid, _, StrEq("rbd"),
+                     StrEq("mirror_image_snapshot_unlink_peer"),
+                     ContentsEqual(bl), _, _, _))
+      .WillOnce(Invoke([&mock_image_ctx, snap_id, peer_uuid, r](auto&&... args) -> int {
+                         if (r == 0) {
+                           auto it = mock_image_ctx.snap_info.find(snap_id);
+                           EXPECT_NE(it, mock_image_ctx.snap_info.end());
+                           auto info =
+                             boost::get<cls::rbd::MirrorSnapshotNamespace>(
+                               &it->second.snap_namespace);
+                           EXPECT_NE(nullptr, info);
+                           EXPECT_NE(0, info->mirror_peer_uuids.erase(
+                                       peer_uuid));
+                         }
+                         return r;
+                       }));
+  }
+
+  void expect_notify_update(MockTestImageCtx &mock_image_ctx, int r) {
+    EXPECT_CALL(mock_image_ctx, notify_update(_))
+      .WillOnce(CompleteContext(r, mock_image_ctx.image_ctx->op_work_queue));
+  }
+
+  void expect_remove_snapshot(MockTestImageCtx &mock_image_ctx,
+                              uint64_t snap_id, int r) {
+    EXPECT_CALL(*mock_image_ctx.operations, snap_remove(_, _, _))
+      .WillOnce(Invoke([&mock_image_ctx, snap_id, r](
+                           const cls::rbd::SnapshotNamespace &snap_namespace,
+                           const std::string &snap_name, Context *on_finish) {
+                         if (r == 0) {
+                           auto it = mock_image_ctx.snap_info.find(snap_id);
+                           EXPECT_NE(it, mock_image_ctx.snap_info.end());
+                           EXPECT_EQ(it->second.snap_namespace, snap_namespace);
+                           EXPECT_EQ(it->second.name, snap_name);
+                           mock_image_ctx.snap_info.erase(it);
+                         }
+                         mock_image_ctx.image_ctx->op_work_queue->queue(
+                           on_finish, r);
+                       }));
+  }
+};
+
+TEST_F(TestMockMirrorSnapshotUnlinkPeerRequest, Success) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  cls::rbd::MirrorSnapshotNamespace ns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"peer1_uuid", "peer2_uuid"},
+    "", CEPH_NOSNAP};
+  auto snap_id = snap_create(mock_image_ctx, ns, "mirror_snap");
+
+  expect_get_snap_info(mock_image_ctx, snap_id);
+
+  InSequence seq;
+
+  expect_is_refresh_required(mock_image_ctx, true);
+  expect_refresh_image(mock_image_ctx, 0);
+  expect_unlink_peer(mock_image_ctx, snap_id, "peer1_uuid", 0);
+  expect_notify_update(mock_image_ctx, 0);
+  expect_refresh_image(mock_image_ctx, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockUnlinkPeerRequest(&mock_image_ctx, snap_id, "peer1_uuid",
+                                       &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotUnlinkPeerRequest, RemoveSnapshot) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  cls::rbd::MirrorSnapshotNamespace ns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"peer_uuid"},
+    "", CEPH_NOSNAP};
+  auto snap_id = snap_create(mock_image_ctx, ns, "mirror_snap");
+  snap_create(mock_image_ctx, ns, "mirror_snap2");
+
+  expect_get_snap_info(mock_image_ctx, snap_id);
+
+  InSequence seq;
+
+  expect_is_refresh_required(mock_image_ctx, true);
+  expect_refresh_image(mock_image_ctx, 0);
+  expect_remove_snapshot(mock_image_ctx, snap_id, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockUnlinkPeerRequest(&mock_image_ctx, snap_id, "peer_uuid",
+                                       &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotUnlinkPeerRequest, SnapshotRemoveEmptyPeers) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  cls::rbd::MirrorSnapshotNamespace ns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {},
+    "", CEPH_NOSNAP};
+  auto snap_id = snap_create(mock_image_ctx, ns, "mirror_snap");
+  ns.mirror_peer_uuids = {"peer_uuid"};
+  snap_create(mock_image_ctx, ns, "mirror_snap2");
+
+  expect_get_snap_info(mock_image_ctx, snap_id);
+
+  InSequence seq;
+
+  expect_is_refresh_required(mock_image_ctx, true);
+  expect_refresh_image(mock_image_ctx, 0);
+  expect_remove_snapshot(mock_image_ctx, snap_id, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockUnlinkPeerRequest(&mock_image_ctx, snap_id, "peer_uuid",
+                                       &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotUnlinkPeerRequest, SnapshotDNE) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  expect_get_snap_info(mock_image_ctx, 123);
+
+  InSequence seq;
+
+  expect_is_refresh_required(mock_image_ctx, true);
+  expect_refresh_image(mock_image_ctx, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockUnlinkPeerRequest(&mock_image_ctx, 123, "peer_uuid", &ctx);
+  req->send();
+  ASSERT_EQ(-ENOENT, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotUnlinkPeerRequest, PeerDNE) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  cls::rbd::MirrorSnapshotNamespace ns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"peer_uuid"},
+    "", CEPH_NOSNAP};
+  auto snap_id = snap_create(mock_image_ctx, ns, "mirror_snap");
+
+  expect_get_snap_info(mock_image_ctx, snap_id);
+
+  InSequence seq;
+
+  expect_is_refresh_required(mock_image_ctx, true);
+  expect_refresh_image(mock_image_ctx, 0);
+
+  C_SaferCond ctx;
+  auto req = new MockUnlinkPeerRequest(&mock_image_ctx, snap_id, "unknown_peer",
+                                       &ctx);
+  req->send();
+  ASSERT_EQ(0, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotUnlinkPeerRequest, InvalidSnapshot) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  cls::rbd::UserSnapshotNamespace ns;
+  auto snap_id = snap_create(mock_image_ctx, ns, "user_snap");
+
+  expect_get_snap_info(mock_image_ctx, snap_id);
+
+  InSequence seq;
+
+  expect_is_refresh_required(mock_image_ctx, false);
+
+  C_SaferCond ctx;
+  auto req = new MockUnlinkPeerRequest(&mock_image_ctx, snap_id, "peer_uuid",
+                                       &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotUnlinkPeerRequest, RefreshError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  InSequence seq;
+
+  expect_is_refresh_required(mock_image_ctx, true);
+  expect_refresh_image(mock_image_ctx, -EINVAL);
+
+  C_SaferCond ctx;
+  auto req = new MockUnlinkPeerRequest(&mock_image_ctx, 123, "peer_uuid", &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotUnlinkPeerRequest, UnlinkError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  cls::rbd::MirrorSnapshotNamespace ns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"peer1_uuid", "peer2_uuid"},
+    "", CEPH_NOSNAP};
+  auto snap_id = snap_create(mock_image_ctx, ns, "mirror_snap");
+
+  expect_get_snap_info(mock_image_ctx, snap_id);
+
+  InSequence seq;
+
+  expect_is_refresh_required(mock_image_ctx, false);
+  expect_unlink_peer(mock_image_ctx, snap_id, "peer1_uuid", -EINVAL);
+
+  C_SaferCond ctx;
+  auto req = new MockUnlinkPeerRequest(&mock_image_ctx, snap_id, "peer1_uuid",
+                                       &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotUnlinkPeerRequest, NotifyError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  cls::rbd::MirrorSnapshotNamespace ns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"peer1_uuid", "peer2_uuid"},
+    "", CEPH_NOSNAP};
+  auto snap_id = snap_create(mock_image_ctx, ns, "mirror_snap");
+
+  expect_get_snap_info(mock_image_ctx, snap_id);
+
+  InSequence seq;
+
+  expect_is_refresh_required(mock_image_ctx, false);
+  expect_unlink_peer(mock_image_ctx, snap_id, "peer1_uuid", 0);
+  expect_notify_update(mock_image_ctx, -EINVAL);
+
+  C_SaferCond ctx;
+  auto req = new MockUnlinkPeerRequest(&mock_image_ctx, snap_id, "peer1_uuid",
+                                       &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+TEST_F(TestMockMirrorSnapshotUnlinkPeerRequest, RemoveSnapshotError) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+  cls::rbd::MirrorSnapshotNamespace ns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"peer_uuid"},
+    "", CEPH_NOSNAP};
+  auto snap_id = snap_create(mock_image_ctx, ns, "mirror_snap");
+  snap_create(mock_image_ctx, ns, "mirror_snap2");
+
+  expect_get_snap_info(mock_image_ctx, snap_id);
+
+  InSequence seq;
+
+  expect_is_refresh_required(mock_image_ctx, false);
+  expect_remove_snapshot(mock_image_ctx, snap_id, -EINVAL);
+
+  C_SaferCond ctx;
+  auto req = new MockUnlinkPeerRequest(&mock_image_ctx, snap_id, "peer_uuid",
+                                       &ctx);
+  req->send();
+  ASSERT_EQ(-EINVAL, ctx.wait());
+}
+
+} // namespace snapshot
+} // namespace mirror
+} // namespace librbd
diff --git a/src/test/librbd/mirror/snapshot/test_mock_Utils.cc b/src/test/librbd/mirror/snapshot/test_mock_Utils.cc
new file mode 100644
index 000000000..410dc3eba
--- /dev/null
+++ b/src/test/librbd/mirror/snapshot/test_mock_Utils.cc
@@ -0,0 +1,177 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "include/stringify.h"
+#include "test/librbd/test_mock_fixture.h"
+#include "test/librbd/test_support.h"
+#include "test/librbd/mock/MockImageCtx.h"
+#include "test/librbd/mock/MockOperations.h"
+#include "test/librados_test_stub/MockTestMemIoCtxImpl.h"
+#include "test/librados_test_stub/MockTestMemRadosClient.h"
+#include "librbd/mirror/snapshot/UnlinkPeerRequest.h"
+#include "librbd/mirror/snapshot/Utils.h"
+
+namespace librbd {
+
+namespace {
+
+struct MockTestImageCtx : public MockImageCtx {
+  explicit MockTestImageCtx(librbd::ImageCtx& image_ctx) : MockImageCtx(image_ctx) {
+  }
+};
+
+} // anonymous namespace
+} // namespace librbd
+
+// template definitions
+#include "librbd/mirror/snapshot/Utils.cc"
+template bool librbd::mirror::snapshot::util::can_create_primary_snapshot(
+  librbd::MockTestImageCtx *image_ctx, bool demoted, bool force,
+  bool* requires_orphan, uint64_t *rollback_snap_id);
+template bool librbd::mirror::snapshot::util::can_create_non_primary_snapshot(
+  librbd::MockTestImageCtx *image_ctx);
+
+namespace librbd {
+namespace mirror {
+namespace snapshot {
+
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::InSequence;
+using ::testing::Invoke;
+using ::testing::Return;
+using ::testing::StrEq;
+using ::testing::WithArg;
+
+class TestMockMirrorSnapshotUtils : public TestMockFixture {
+public:
+  uint64_t m_snap_seq = 0;
+
+  uint64_t snap_create(MockTestImageCtx &mock_image_ctx,
+                       const cls::rbd::SnapshotNamespace &ns,
+                       const std::string& snap_name) {
+    EXPECT_TRUE(mock_image_ctx.snap_info.insert(
+                  {++m_snap_seq,
+                   SnapInfo{snap_name, ns, 0, {}, 0, 0, {}}}).second);
+    return m_snap_seq;
+  }
+};
+
+TEST_F(TestMockMirrorSnapshotUtils, CanCreatePrimarySnapshot) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  // no previous mirror snapshots found
+  bool requires_orphan;
+  uint64_t rollback_snap_id;
+  ASSERT_TRUE(util::can_create_primary_snapshot(&mock_image_ctx, false, false,
+                                                &requires_orphan,
+                                                &rollback_snap_id));
+  ASSERT_FALSE(requires_orphan);
+  ASSERT_EQ(rollback_snap_id, CEPH_NOSNAP);
+
+  cls::rbd::MirrorSnapshotNamespace nns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_NON_PRIMARY, {}, "mirror_uuid", 123};
+  nns.complete = true;
+  auto copied_snap_id = snap_create(mock_image_ctx, nns, "NPS1");
+
+  // without force, previous snapshot is non-primary
+  ASSERT_FALSE(util::can_create_primary_snapshot(&mock_image_ctx, false, false,
+                                                 nullptr, nullptr));
+
+  // demoted, previous snapshot is non-primary
+  ASSERT_FALSE(util::can_create_primary_snapshot(&mock_image_ctx, true, true,
+                                                 nullptr, nullptr));
+
+  // previous non-primary snapshot is copied
+  ASSERT_TRUE(util::can_create_primary_snapshot(&mock_image_ctx, false, true,
+                                                &requires_orphan,
+                                                &rollback_snap_id));
+  ASSERT_TRUE(requires_orphan);
+  ASSERT_EQ(rollback_snap_id, CEPH_NOSNAP);
+
+  nns.complete = false;
+  snap_create(mock_image_ctx, nns, "NPS2");
+
+  // previous non-primary snapshot is not copied yet
+  ASSERT_FALSE(util::can_create_primary_snapshot(&mock_image_ctx, false, true,
+                                                 nullptr, nullptr));
+
+  // can rollback
+  ASSERT_TRUE(util::can_create_primary_snapshot(&mock_image_ctx, false, true,
+                                                nullptr, &rollback_snap_id));
+  ASSERT_EQ(rollback_snap_id, copied_snap_id);
+
+  nns.state = cls::rbd::MIRROR_SNAPSHOT_STATE_NON_PRIMARY_DEMOTED;
+  snap_create(mock_image_ctx, nns, "NPS3");
+
+  // previous non-primary snapshot is orphan
+  ASSERT_TRUE(util::can_create_primary_snapshot(&mock_image_ctx, false, true,
+                                                nullptr, nullptr));
+
+  cls::rbd::MirrorSnapshotNamespace pns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY_DEMOTED, {"uuid"}, "", CEPH_NOSNAP};
+  snap_create(mock_image_ctx, pns, "PS1");
+
+  // previous primary snapshot is demoted, no force
+  ASSERT_FALSE(util::can_create_primary_snapshot(&mock_image_ctx, false, false,
+                                                 nullptr, nullptr));
+
+  // previous primary snapshot is demoted, force
+  ASSERT_TRUE(util::can_create_primary_snapshot(&mock_image_ctx, false, true,
+                                                nullptr, nullptr));
+
+  pns.state = cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY;
+  snap_create(mock_image_ctx, pns, "PS2");
+
+  // previous snapshot is not demoted primary
+  ASSERT_TRUE(util::can_create_primary_snapshot(&mock_image_ctx, false, false,
+                                                nullptr, nullptr));
+}
+
+TEST_F(TestMockMirrorSnapshotUtils, CanCreateNonPrimarySnapshot) {
+  REQUIRE_FORMAT_V2();
+
+  librbd::ImageCtx *ictx;
+  ASSERT_EQ(0, open_image(m_image_name, &ictx));
+
+  MockTestImageCtx mock_image_ctx(*ictx);
+
+  // no previous mirror snapshots found
+  ASSERT_TRUE(util::can_create_non_primary_snapshot(&mock_image_ctx));
+
+  cls::rbd::MirrorSnapshotNamespace nns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_NON_PRIMARY, {}, "mirror_uuid", 123};
+  snap_create(mock_image_ctx, nns, "NPS1");
+
+  // previous non-primary snapshot is not copied yet
+  ASSERT_FALSE(util::can_create_non_primary_snapshot(&mock_image_ctx));
+
+  nns.complete = true;
+  snap_create(mock_image_ctx, nns, "NPS2");
+
+  // previous non-primary snapshot is copied
+  ASSERT_TRUE(util::can_create_non_primary_snapshot(&mock_image_ctx));
+
+  cls::rbd::MirrorSnapshotNamespace pns{
+    cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"uuid"}, "", CEPH_NOSNAP};
+  snap_create(mock_image_ctx, pns, "PS1");
+
+  // previous primary snapshot is not in demoted state
+  ASSERT_FALSE(util::can_create_non_primary_snapshot(&mock_image_ctx));
+
+  pns.state = cls::rbd::MIRROR_SNAPSHOT_STATE_NON_PRIMARY_DEMOTED;
+  snap_create(mock_image_ctx, pns, "PS2");
+
+  // previous primary snapshot is in demoted state
+  ASSERT_TRUE(util::can_create_non_primary_snapshot(&mock_image_ctx));
+}
+
+} // namespace snapshot
+} // namespace mirror
+} // namespace librbd
+