Add option to disable cleaner

This allows to avoid allocating cleaner metadata section and effectively
save up to 20% of metadata memory footprint.

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>

src/metadata/metadata.c

@@ -638,7 +638,8 @@ static void ocf_metadata_flush_unlock_collision_page(
  * Initialize hash metadata interface
  */
 int ocf_metadata_init_variable_size(struct ocf_cache *cache,
-		uint64_t device_size, ocf_cache_line_size_t line_size)
+		uint64_t device_size, ocf_cache_line_size_t line_size,
+		bool cleaner_disabled)
 {
 	int result = 0;
 	uint32_t i = 0;
@@ -688,6 +689,12 @@ int ocf_metadata_init_variable_size(struct ocf_cache *cache,
 			raw->raw_type = metadata_raw_type_atomic;
 		}
 
+		if (i == metadata_segment_cleaning && cleaner_disabled) {
+			raw->entry_size = 0;
+			raw->entries_in_page = 1;
+			continue;
+		}
+
 		/* Entry size configuration */
 		raw->entry_size
 			= ocf_metadata_get_element_size(i, line_size);
@@ -715,6 +722,9 @@ int ocf_metadata_init_variable_size(struct ocf_cache *cache,
 	 */
 	for (i = metadata_segment_variable_size_start;
 			i < metadata_segment_max; i++) {
+		if (i == metadata_segment_cleaning && cleaner_disabled)
+			continue;
+
 		if (i == metadata_segment_collision) {
 			lock_page =
 				ocf_metadata_flush_lock_collision_page;
@@ -779,6 +789,7 @@ finalize:
 
 	cache->conf_meta->cachelines = ctrl->cachelines;
 	cache->conf_meta->line_size = line_size;
+	cache->conf_meta->cleaner_disabled = cleaner_disabled;
 
 	ocf_metadata_raw_info(cache, ctrl);
 
@@ -1620,6 +1631,7 @@ static void ocf_metadata_load_properties_cmpl(
 	properties.shutdown_status = superblock->clean_shutdown;
 	properties.dirty_flushed = superblock->dirty_flushed;
 	properties.cache_name = superblock->name;
+	properties.cleaner_disabled = superblock->cleaner_disabled;
 
 	OCF_CMPL_RET(priv, 0, &properties);
 }

src/metadata/metadata.h

@@ -41,10 +41,12 @@ int ocf_metadata_init(struct ocf_cache *cache,
  * @param cache - Cache instance
  * @param device_size - Device size in bytes
  * @param cache_line_size Cache line size
+ * @param cleaner_disabled Cleaner is disabled
  * @return 0 - Operation success otherwise failure
  */
 int ocf_metadata_init_variable_size(struct ocf_cache *cache,
-		uint64_t device_size, ocf_cache_line_size_t cache_line_size);
+		uint64_t device_size, ocf_cache_line_size_t line_size,
+		bool cleaner_disabled);
 
 /**
  * @brief Initialize collision table
@@ -201,6 +203,7 @@ struct ocf_metadata_load_properties {
 	ocf_cache_mode_t cache_mode;
 	ocf_cache_line_size_t line_size;
 	char *cache_name;
+	bool cleaner_disabled;
 };
 
 typedef void (*ocf_metadata_load_properties_end_t)(void *priv, int error,

src/metadata/metadata_cleaning_policy.c

@@ -18,6 +18,8 @@ ocf_metadata_get_cleaning_policy(struct ocf_cache *cache,
 	struct ocf_metadata_ctrl *ctrl
 		= (struct ocf_metadata_ctrl *) cache->metadata.priv;
 
+	ENV_BUG_ON(cache->conf_meta->cleaner_disabled);
+
 	return ocf_metadata_raw_wr_access(cache,
 			&(ctrl->raw_desc[metadata_segment_cleaning]), line);
 }

src/metadata/metadata_superblock.c

@@ -110,8 +110,11 @@ static void ocf_metadata_store_segment(ocf_pipeline_t pipeline,
 int ocf_metadata_validate_superblock(ocf_ctx_t ctx,
 		struct ocf_superblock_config *superblock)
 {
+	const char *segment_name;
 	uint32_t crc;
 
+	segment_name = ocf_metadata_segment_names[metadata_segment_sb_config];
+
 	if (superblock->magic_number != CACHE_MAGIC_NUMBER) {
 		ocf_log(ctx, log_info, "Cannot detect pre-existing metadata\n");
 		return -OCF_ERR_NO_METADATA;
@@ -178,6 +181,14 @@ int ocf_metadata_validate_superblock(ocf_ctx_t ctx,
 		return -OCF_ERR_INVAL;
 	}
 
+	if (superblock->cleaner_disabled &&
+			superblock->cleaning_policy_type != ocf_cleaning_nop) {
+		ocf_log(ctx, log_err, "Loading %s: cleaner is disabled, but "
+				"cleaning policy is not set to nop!\n",
+				segment_name);
+		return -OCF_ERR_INVAL;
+	}
+
 	if (superblock->promotion_policy_type < 0 ||
 			superblock->promotion_policy_type >=
 					ocf_promotion_max) {

src/metadata/metadata_superblock.h

@@ -45,6 +45,7 @@ struct ocf_superblock_config {
 	unsigned long valid_core_bitmap[(OCF_CORE_MAX /
 			(sizeof(unsigned long) * 8)) + 1];
 
+	bool cleaner_disabled;
 	ocf_cleaning_t cleaning_policy_type;
 	struct cleaning_policy_config cleaning[CLEANING_POLICY_TYPE_MAX];