diff --git a/tests/unit/tests/engine/engine_common.c/prepare_clines_hit.c b/tests/unit/tests/engine/engine_common.c/prepare_clines_hit.c
new file mode 100644
index 0000000..d66bc8a
--- /dev/null
+++ b/tests/unit/tests/engine/engine_common.c/prepare_clines_hit.c
@@ -0,0 +1,198 @@
+/*
+ * <tested_file_path>src/engine/engine_common.c</tested_file_path>
+ * <tested_function>ocf_prepare_clines_hit</tested_function>
+ * <functions_to_leave>
+ *	INSERT HERE LIST OF FUNCTIONS YOU WANT TO LEAVE
+ *	ONE FUNCTION PER LINE
+ * </functions_to_leave>
+ */
+
+#undef static
+
+#undef inline
+
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <setjmp.h>
+#include <cmocka.h>
+#include "print_desc.h"
+
+#include "ocf/ocf.h"
+#include "../ocf_priv.h"
+#include "../ocf_cache_priv.h"
+#include "../ocf_queue_priv.h"
+#include "../ocf_freelist.h"
+#include "engine_common.h"
+#include "engine_debug.h"
+#include "../utils/utils_cache_line.h"
+#include "../ocf_request.h"
+#include "../utils/utils_cleaner.h"
+#include "../utils/utils_part.h"
+#include "../metadata/metadata.h"
+#include "../eviction/eviction.h"
+#include "../promotion/promotion.h"
+#include "../concurrency/ocf_concurrency.h"
+
+#include "engine/engine_common.c/prepare_clines_miss_generated_wraps.c"
+
+void __wrap_ocf_req_hash_unlock_rd(struct ocf_request *req)
+{
+}
+
+uint32_t __wrap_ocf_part_check_space(struct ocf_request *req,
+		uint32_t *to_evict)
+{
+	return mock();
+}
+
+int __wrap_lock_clines(struct ocf_request *req,
+		const struct ocf_engine_callbacks *engine_cbs)
+{
+	function_called();
+	return mock();
+}
+
+void __wrap_ocf_metadata_start_exclusive_access(
+		struct ocf_metadata_lock *metadata_lock)
+{
+}
+
+void __wrap_ocf_metadata_end_exclusive_access(
+		struct ocf_metadata_lock *metadata_lock)
+{
+}
+
+int __wrap_space_managment_evict_do(struct ocf_cache *cache,
+		struct ocf_request *req, uint32_t evict_cline_no)
+{
+	return mock();
+}
+
+bool __wrap_ocf_part_is_enabled(struct ocf_user_part *target_part)
+{
+	return mock();
+}
+
+bool __wrap_ocf_engine_needs_repart(struct ocf_request *req)
+{
+	return mock();
+}
+
+void __wrap_ocf_req_set_mapping_error(struct ocf_request *req)
+{
+	function_called();
+}
+
+static void ocf_prepare_clines_hit_test01(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Request is hit and part is enabled\n");
+	will_return(__wrap_ocf_part_is_enabled, true);
+	will_return(__wrap_ocf_engine_needs_repart, false);
+
+	will_return(__wrap_lock_clines, 0);
+	expect_function_call(__wrap_lock_clines);
+
+	assert_int_equal(ocf_prepare_clines_hit(&req, NULL), 0);
+}
+
+static void ocf_prepare_clines_hit_test02(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Request is hit but part is disabled - tigger eviction\n");
+	will_return(__wrap_ocf_part_is_enabled, false);
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_DISABLED);
+
+	expect_function_call(__wrap_ocf_req_set_mapping_error);
+
+	assert_int_equal(ocf_prepare_clines_hit(&req, NULL), -OCF_ERR_NO_LOCK);
+}
+
+static void ocf_prepare_clines_hit_test03(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Request needs repart, part has enough of a free space\n");
+	will_return(__wrap_ocf_part_is_enabled, true);
+	will_return(__wrap_ocf_engine_needs_repart, true);
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_HAS_SPACE);
+
+	expect_function_call(__wrap_lock_clines);
+	will_return(__wrap_lock_clines, 0);
+
+	assert_int_equal(ocf_prepare_clines_hit(&req, NULL), 0);
+}
+
+static void ocf_prepare_clines_hit_test04(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Request needs repart, eviction fails\n");
+	will_return(__wrap_ocf_part_is_enabled, true);
+	will_return(__wrap_ocf_engine_needs_repart, true);
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+	will_return(__wrap_space_managment_evict_do, LOOKUP_MISS);
+	expect_function_call(__wrap_ocf_req_set_mapping_error);
+
+	assert_int_equal(ocf_prepare_clines_hit(&req, NULL), -OCF_ERR_NO_LOCK);
+}
+
+static void ocf_prepare_clines_hit_test05(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Request needs repart, eviction passed, no lock\n");
+
+	will_return(__wrap_ocf_part_is_enabled, true);
+	will_return(__wrap_ocf_engine_needs_repart, true);
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+	will_return(__wrap_space_managment_evict_do, LOOKUP_HIT);
+
+	expect_function_call(__wrap_lock_clines);
+	will_return(__wrap_lock_clines, OCF_ERR_NO_LOCK);
+
+	will_return(__wrap_ocf_part_is_enabled, true);
+
+	assert_int_equal(ocf_prepare_clines_hit(&req, NULL), OCF_ERR_NO_LOCK);
+}
+
+static void ocf_prepare_clines_hit_test06(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Partition is disabled, but has some cachelines assigned.\n");
+	print_test_description("Trigger eviction and but don't lock cachelines\n");
+
+	will_return(__wrap_ocf_part_is_enabled, false);
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+	will_return(__wrap_space_managment_evict_do, LOOKUP_HIT);
+
+	will_return(__wrap_ocf_part_is_enabled, false);
+	expect_function_call(__wrap_ocf_req_set_mapping_error);
+
+	assert_int_equal(ocf_prepare_clines_hit(&req, NULL), -OCF_ERR_NO_LOCK);
+}
+
+int main(void)
+{
+	const struct CMUnitTest tests[] = {
+		cmocka_unit_test(ocf_prepare_clines_hit_test01),
+		cmocka_unit_test(ocf_prepare_clines_hit_test02),
+		cmocka_unit_test(ocf_prepare_clines_hit_test03),
+		cmocka_unit_test(ocf_prepare_clines_hit_test04),
+		cmocka_unit_test(ocf_prepare_clines_hit_test05),
+		cmocka_unit_test(ocf_prepare_clines_hit_test06)
+	};
+
+	print_message("Unit test for ocf_prepare_clines_hit\n");
+
+	return cmocka_run_group_tests(tests, NULL, NULL);
+}
diff --git a/tests/unit/tests/engine/engine_common.c/prepare_clines_miss.c b/tests/unit/tests/engine/engine_common.c/prepare_clines_miss.c
new file mode 100644
index 0000000..81fec82
--- /dev/null
+++ b/tests/unit/tests/engine/engine_common.c/prepare_clines_miss.c
@@ -0,0 +1,263 @@
+/*
+ * <tested_file_path>src/engine/engine_common.c</tested_file_path>
+ * <tested_function>ocf_prepare_clines_miss</tested_function>
+ * <functions_to_leave>
+ *	INSERT HERE LIST OF FUNCTIONS YOU WANT TO LEAVE
+ *	ONE FUNCTION PER LINE
+ * </functions_to_leave>
+ */
+
+#undef static
+
+#undef inline
+
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <setjmp.h>
+#include <cmocka.h>
+#include "print_desc.h"
+
+#include "ocf/ocf.h"
+#include "../ocf_priv.h"
+#include "../ocf_cache_priv.h"
+#include "../ocf_queue_priv.h"
+#include "../ocf_freelist.h"
+#include "engine_common.h"
+#include "engine_debug.h"
+#include "../utils/utils_cache_line.h"
+#include "../ocf_request.h"
+#include "../utils/utils_cleaner.h"
+#include "../utils/utils_part.h"
+#include "../metadata/metadata.h"
+#include "../eviction/eviction.h"
+#include "../promotion/promotion.h"
+#include "../concurrency/ocf_concurrency.h"
+
+#include "engine/engine_common.c/prepare_clines_miss_generated_wraps.c"
+
+void __wrap_ocf_req_hash_lock_upgrade(struct ocf_request *req)
+{
+}
+
+void __wrap_ocf_req_hash_unlock_wr(struct ocf_request *req)
+{
+}
+
+uint32_t __wrap_ocf_part_check_space(struct ocf_request *req,
+		uint32_t *to_evict)
+{
+	return mock();
+}
+
+int __wrap_lock_clines(struct ocf_request *req,
+		const struct ocf_engine_callbacks *engine_cbs)
+{
+	function_called();
+	return mock();
+}
+
+void __wrap_ocf_metadata_start_exclusive_access(
+		struct ocf_metadata_lock *metadata_lock)
+{
+}
+
+void __wrap_ocf_metadata_end_exclusive_access(
+		struct ocf_metadata_lock *metadata_lock)
+{
+}
+
+int __wrap_space_managment_evict_do(struct ocf_cache *cache,
+		struct ocf_request *req, uint32_t evict_cline_no)
+{
+	function_called();
+	return mock();
+}
+
+bool __wrap_ocf_part_is_enabled(struct ocf_user_part *target_part)
+{
+	return mock();
+}
+
+void __wrap_ocf_engine_map(struct ocf_request *req)
+{
+	function_called();
+}
+
+bool __wrap_ocf_req_test_mapping_error(struct ocf_request *req)
+{
+	return mock();
+}
+
+void __wrap_ocf_req_set_mapping_error(struct ocf_request *req)
+{
+	function_called();
+}
+
+static void ocf_prepare_clines_miss_test01(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Target part is disabled and empty\n");
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_DISABLED);
+	expect_function_call(__wrap_ocf_req_set_mapping_error);
+	assert_int_equal(ocf_prepare_clines_miss(&req, NULL), -OCF_ERR_NO_LOCK);
+}
+
+static void ocf_prepare_clines_miss_test02(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Target part is disabled but has cachelines assigned.\n");
+	print_test_description("\tTrigger eviction and mark mapping error\n");
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+
+	expect_function_call(__wrap_space_managment_evict_do);
+	will_return(__wrap_space_managment_evict_do, LOOKUP_MAPPED);
+	will_return(__wrap_ocf_part_is_enabled, false);
+	expect_function_call(__wrap_ocf_req_set_mapping_error);
+
+	assert_int_equal(ocf_prepare_clines_miss(&req, NULL), -OCF_ERR_NO_LOCK);
+}
+
+static void ocf_prepare_clines_miss_test03(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Target part is enabled but doesn't have enough space.\n");
+	print_test_description("\tEviction is ok and cachelines lock is acquired.\n");
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+
+	expect_function_call(__wrap_space_managment_evict_do);
+	will_return(__wrap_space_managment_evict_do, LOOKUP_MAPPED);
+	will_return(__wrap_ocf_part_is_enabled, true);
+
+	expect_function_call(__wrap_ocf_engine_map);
+
+	will_return(__wrap_ocf_req_test_mapping_error, false);
+
+	will_return(__wrap_lock_clines, 0);
+	expect_function_call(__wrap_lock_clines);
+
+	assert_int_equal(ocf_prepare_clines_miss(&req, NULL), 0);
+}
+
+static void ocf_prepare_clines_miss_test04(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Target part is enabled but doesn't have enough space.\n");
+	print_test_description("\tEviction failed\n");
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+
+	expect_function_call(__wrap_space_managment_evict_do);
+	will_return(__wrap_space_managment_evict_do, LOOKUP_MISS);
+	expect_function_call(__wrap_ocf_req_set_mapping_error);
+
+	assert_int_equal(ocf_prepare_clines_miss(&req, NULL), -OCF_ERR_NO_LOCK);
+}
+
+static void ocf_prepare_clines_miss_test05(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Target part is enabled but doesn't have enough space.\n");
+	print_test_description("Eviction is ok, but mapping failed.\n");
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+
+	expect_function_call(__wrap_space_managment_evict_do);
+	will_return(__wrap_space_managment_evict_do, LOOKUP_HIT);
+
+	will_return(__wrap_ocf_part_is_enabled, true);
+
+	expect_function_call(__wrap_ocf_engine_map);
+	will_return(__wrap_ocf_req_test_mapping_error, true);
+
+	assert_int_equal(ocf_prepare_clines_miss(&req, NULL), -OCF_ERR_NO_LOCK);
+}
+
+static void ocf_prepare_clines_miss_test06(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Target part is enabled but doesn't have enough space.\n");
+	print_test_description("Eviction and mapping were ok, but failed to lock cachelines.\n");
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+
+	expect_function_call(__wrap_space_managment_evict_do);
+	will_return(__wrap_space_managment_evict_do, LOOKUP_HIT);
+
+	will_return(__wrap_ocf_part_is_enabled, true);
+
+	expect_function_call(__wrap_ocf_engine_map);
+	will_return(__wrap_ocf_req_test_mapping_error, false);
+
+	expect_function_call(__wrap_lock_clines);
+	will_return(__wrap_lock_clines, -OCF_ERR_NO_LOCK);
+
+	expect_function_call(__wrap_ocf_req_set_mapping_error);
+
+	assert_int_equal(ocf_prepare_clines_miss(&req, NULL), -OCF_ERR_NO_LOCK);
+}
+
+static void ocf_prepare_clines_miss_test07(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Target part is enabled but doesn't have enough space.\n");
+	print_test_description("Eviction and mapping were ok, lock not acquired.\n");
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+	will_return(__wrap_ocf_part_check_space, OCF_PART_IS_FULL);
+
+	expect_function_call(__wrap_space_managment_evict_do);
+	will_return(__wrap_space_managment_evict_do, LOOKUP_HIT);
+
+	will_return(__wrap_ocf_part_is_enabled, true);
+
+	expect_function_call(__wrap_ocf_engine_map);
+	will_return(__wrap_ocf_req_test_mapping_error, false);
+
+	expect_function_call(__wrap_lock_clines);
+	will_return(__wrap_lock_clines, OCF_LOCK_NOT_ACQUIRED);
+
+	assert_int_equal(ocf_prepare_clines_miss(&req, NULL), OCF_LOCK_NOT_ACQUIRED);
+}
+
+static void ocf_prepare_clines_miss_test08(void **state)
+{
+	struct ocf_request req = {};
+	print_test_description("Target part is enabled has enough space.\n");
+	print_test_description("\tMapping and cacheline lock are both ok\n");
+
+	will_return(__wrap_ocf_part_check_space, OCF_PART_HAS_SPACE);
+
+	expect_function_call(__wrap_ocf_engine_map);
+	will_return(__wrap_ocf_req_test_mapping_error, false);
+
+	expect_function_call(__wrap_lock_clines);
+	will_return(__wrap_lock_clines, OCF_LOCK_ACQUIRED);
+
+	assert_int_equal(ocf_prepare_clines_miss(&req, NULL), OCF_LOCK_ACQUIRED);
+}
+
+int main(void)
+{
+	const struct CMUnitTest tests[] = {
+		cmocka_unit_test(ocf_prepare_clines_miss_test01),
+		cmocka_unit_test(ocf_prepare_clines_miss_test02),
+		cmocka_unit_test(ocf_prepare_clines_miss_test03),
+		cmocka_unit_test(ocf_prepare_clines_miss_test04),
+		cmocka_unit_test(ocf_prepare_clines_miss_test05),
+		cmocka_unit_test(ocf_prepare_clines_miss_test06),
+		cmocka_unit_test(ocf_prepare_clines_miss_test07),
+		cmocka_unit_test(ocf_prepare_clines_miss_test08)
+	};
+
+	print_message("Unit test for ocf_prepare_clines_miss\n");
+
+	return cmocka_run_group_tests(tests, NULL, NULL);
+}