Introduce cache bind operation

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

casadm/cas_lib.c

@@ -68,6 +68,7 @@ static const char *cache_states_name[ocf_cache_state_max + 1] = {
 		[ocf_cache_state_stopping] = "Stopping",
 		[ocf_cache_state_initializing] = "Initializing",
 		[ocf_cache_state_incomplete] = "Incomplete",
+		[ocf_cache_state_passive] = "Passive",
 		[ocf_cache_state_max] = "Unknown",
 };
 
@@ -2775,8 +2776,12 @@ int list_caches(unsigned int list_format, bool by_id_path)
 					cache_mode_to_name(curr_cache->mode));
 		} else {
 			tmp_status = get_cache_state_name(curr_cache->state);
-			snprintf(mode_string, sizeof(mode_string), "%s",
+			if (curr_cache->state & (1 << ocf_cache_state_passive)) {
-					cache_mode_to_name(curr_cache->mode));
+				strncpy(mode_string, "-", sizeof(mode_string));
+			} else {
+				snprintf(mode_string, sizeof(mode_string), "%s",
+						cache_mode_to_name(curr_cache->mode));
+			}
 		}
 
 		fprintf(intermediate_file[1], TAG(TREE_BRANCH)

casadm/cas_main.c

@@ -198,6 +198,8 @@ int start_cache_command_handle_option(char *opt, const char **arg)
 		command_args_values.cache_id = atoi(arg[0]);
 	} else if (!strcmp(opt, "load")) {
 		command_args_values.state = CACHE_INIT_LOAD;
+	} else if (!strcmp(opt, "bind")) {
+		command_args_values.state = CACHE_INIT_BIND;
 	} else if (!strcmp(opt, "cache-device")) {
 		if(validate_device_name(arg[0]) == FAILURE)
 			return FAILURE;
@@ -243,6 +245,7 @@ static cli_option start_options[] = {
 	{'d', "cache-device", CACHE_DEVICE_DESC, 1, "DEVICE", CLI_OPTION_REQUIRED},
 	{'i', "cache-id", CACHE_ID_DESC_LONG, 1, "ID", 0},
 	{'l', "load", "Load cache metadata from caching device (DANGEROUS - see manual or Admin Guide for details)"},
+	{'b', "bind", "Bind caching device (DANGEROUS - see manual or Admin Guide for details)"},
 	{'f', "force", "Force the creation of cache instance"},
 	{'c', "cache-mode", "Set cache mode from available: {"CAS_CLI_HELP_START_CACHE_MODES"} "CAS_CLI_HELP_START_CACHE_MODES_FULL"; without this parameter Write-Through will be set by default", 1, "NAME"},
 	{'x', "cache-line-size", "Set cache line size in kibibytes: {4,8,16,32,64}[KiB] (default: %d)", 1, "NUMBER",  CLI_OPTION_DEFAULT_INT, 0, 0, ocf_cache_line_size_default / KiB},
@@ -293,6 +296,11 @@ int handle_start()
 		return FAILURE;
 	}
 
+	if (command_args_values.state == CACHE_INIT_BIND && command_args_values.force) {
+		cas_printf(LOG_ERR, "Use of 'bind' and 'force' simultaneously is forbidden.\n");
+		return FAILURE;
+	}
+
 	cache_device = open(command_args_values.cache_device, O_RDONLY);
 
 	if (cache_device < 0) {

modules/cas_cache/classifier.c

@@ -1215,7 +1215,8 @@ ocf_part_id_t cas_cls_classify(ocf_cache_t cache, struct bio *bio)
 	cas_cls_eval_t ret;
 
 	cls = cas_get_classifier(cache);
-	ENV_BUG_ON(!cls);
+	if (!cls)
+		return 0;
 
 	_cas_cls_get_bio_context(bio, &io);
 

modules/cas_cache/layer_cache_management.c

@@ -576,7 +576,8 @@ static int exit_instance_finish(void *data)
 	else
 		result = ctx->error;
 
-	cas_cls_deinit(ctx->cache);
+	if (!ocf_cache_is_passive(ctx->cache))
+		cas_cls_deinit(ctx->cache);
 
 	vfree(cache_priv);
 
@@ -1382,19 +1383,6 @@ error_affter_lock:
 	return result;
 }
 
-static int _cache_mngt_create_exported_object(ocf_core_t core, void *cntx)
-{
-	int result;
-
-	result = kcas_core_create_exported_object(core);
-	if (result)
-		return result;
-
-	result = kcas_core_activate_exported_object(core);
-
-	return result;
-}
-
 static int _cache_mngt_remove_core_flush(ocf_cache_t cache,
 		struct kcas_remove_core *cmd)
 {
@@ -1726,7 +1714,20 @@ out_get:
 	return result;
 }
 
-static int _cache_mngt_destroy_exported_object(ocf_core_t core, void *cntx)
+static int _cache_mngt_create_core_exp_obj(ocf_core_t core, void *cntx)
+{
+	int result;
+
+	result = kcas_core_create_exported_object(core);
+	if (result)
+		return result;
+
+	result = kcas_core_activate_exported_object(core);
+
+	return result;
+}
+
+static int _cache_mngt_destroy_core_exp_obj(ocf_core_t core, void *cntx)
 {
 	if (kcas_core_destroy_exported_object(core)) {
 		ocf_cache_t cache = ocf_core_get_cache(core);
@@ -1739,21 +1740,46 @@ static int _cache_mngt_destroy_exported_object(ocf_core_t core, void *cntx)
 	return 0;
 }
 
-static int cache_mngt_initialize_core_objects(ocf_cache_t cache)
+static int cache_mngt_initialize_core_exported_objects(ocf_cache_t cache)
 {
 	int result;
 
-	result = ocf_core_visit(cache, _cache_mngt_create_exported_object, NULL,
+	result = ocf_core_visit(cache, _cache_mngt_create_core_exp_obj, NULL,
 			true);
 	if (result) {
 		/* Need to cleanup */
-		ocf_core_visit(cache, _cache_mngt_destroy_exported_object, NULL,
+		ocf_core_visit(cache, _cache_mngt_destroy_core_exp_obj, NULL,
 				true);
 	}
 
 	return result;
 }
 
+static void cache_mngt_destroy_cache_exp_obj(ocf_cache_t cache)
+{
+	if (kcas_cache_destroy_exported_object(cache)) {
+		printk(KERN_ERR "Cannot destroy %s exported object\n",
+				ocf_cache_get_name(cache));
+	}
+}
+
+static int cache_mngt_initialize_cache_exported_object(ocf_cache_t cache)
+{
+	int result;
+
+	result = kcas_cache_create_exported_object(cache);
+	if (result)
+		return result;
+
+	result = kcas_cache_activate_exported_object(cache);
+	if (result) {
+		cache_mngt_destroy_cache_exp_obj(cache);
+		return result;
+	}
+
+	return 0;
+}
+
 int cache_mngt_prepare_cache_cfg(struct ocf_mngt_cache_config *cfg,
 		struct ocf_mngt_cache_device_config *device_cfg,
 		struct kcas_start_cache *cmd)
@@ -1812,6 +1838,7 @@ int cache_mngt_prepare_cache_cfg(struct ocf_mngt_cache_config *cfg,
 	case CACHE_INIT_LOAD:
 		device_cfg->open_cores = true;
 	case CACHE_INIT_NEW:
+	case CACHE_INIT_BIND:
 		break;
 	default:
 		return -OCF_ERR_INVAL;
@@ -2042,7 +2069,8 @@ out_bdev:
 	return result;
 }
 
-static int _cache_start_finalize(ocf_cache_t cache)
+static int _cache_start_finalize(ocf_cache_t cache,
+		struct kcas_start_cache *cmd)
 {
 	struct cache_priv *cache_priv = ocf_cache_get_priv(cache);
 	struct _cache_mngt_attach_context *ctx = cache_priv->attach_context;
@@ -2050,21 +2078,37 @@ static int _cache_start_finalize(ocf_cache_t cache)
 
 	_cache_mngt_log_cache_device_path(cache, ctx->device_cfg);
 
-	result = cas_cls_init(cache);
+	if (cmd->init_cache != CACHE_INIT_BIND) {
-	if (result) {
+		result = cas_cls_init(cache);
-		ctx->ocf_start_error = result;
+		if (result) {
-		return result;
+			ctx->ocf_start_error = result;
-	}
+			return result;
-	ctx->cls_inited = true;
+		}
-
+		ctx->cls_inited = true;
-	result = cache_mngt_initialize_core_objects(cache);
-	if (result) {
-		ctx->ocf_start_error = result;
-		return result;
 	}
 
-	ocf_core_visit(cache, _cache_mngt_core_device_loaded_visitor,
+	switch(cmd->init_cache) {
-			NULL, false);
+	case CACHE_INIT_LOAD:
+		result = cache_mngt_initialize_core_exported_objects(cache);
+		if (result) {
+			ctx->ocf_start_error = result;
+			return result;
+		}
+		ocf_core_visit(cache, _cache_mngt_core_device_loaded_visitor,
+				NULL, false);
+		break;
+	case CACHE_INIT_BIND:
+		result = cache_mngt_initialize_cache_exported_object(cache);
+		if (result) {
+			ctx->ocf_start_error = result;
+			return result;
+		}
+		break;
+	case CACHE_INIT_NEW:
+		break;
+	default:
+		BUG();
+	}
 
 	init_instance_complete(ctx, cache);
 
@@ -2079,12 +2123,11 @@ int cache_mngt_init_instance(struct ocf_mngt_cache_config *cfg,
 	ocf_cache_t cache;
 	struct cache_priv *cache_priv;
 	int result = 0, rollback_result = 0;
-	bool load = (cmd && cmd->init_cache == CACHE_INIT_LOAD);
 
 	if (!try_module_get(THIS_MODULE))
 		return -KCAS_ERR_SYSTEM;
 
-	if (load)
+	if (cmd->init_cache == CACHE_INIT_LOAD)
 		result = _cache_mngt_check_metadata(cfg, cmd->cache_path_name);
 	if (result) {
 		module_put(THIS_MODULE);
@@ -2134,12 +2177,22 @@ int cache_mngt_init_instance(struct ocf_mngt_cache_config *cfg,
 	cache_priv = ocf_cache_get_priv(cache);
 	cache_priv->attach_context = context;
 
-	if (load) {
+	switch (cmd->init_cache) {
-		ocf_mngt_cache_load(cache, device_cfg,
+	case CACHE_INIT_NEW:
-				_cache_mngt_start_complete, context);
-	} else {
 		ocf_mngt_cache_attach(cache, device_cfg,
 				_cache_mngt_start_complete, context);
+		break;
+	case CACHE_INIT_LOAD:
+		ocf_mngt_cache_load(cache, device_cfg,
+				_cache_mngt_start_complete, context);
+		break;
+	case CACHE_INIT_BIND:
+		ocf_mngt_cache_bind(cache, device_cfg,
+				_cache_mngt_start_complete, context);
+		break;
+	default:
+		result = -OCF_ERR_INVAL;
+		goto err;
 	}
 	result = wait_for_completion_interruptible(&context->async.cmpl);
 
@@ -2150,7 +2203,7 @@ int cache_mngt_init_instance(struct ocf_mngt_cache_config *cfg,
 	if (result)
 		goto err;
 
-	result = _cache_start_finalize(cache);
+	result = _cache_start_finalize(cache, cmd);
 	if (result)
 		goto err;
 
@@ -2474,7 +2527,7 @@ int cache_mngt_exit_instance(const char *cache_name, size_t name_len, int flush)
 	 * this time, so we need to flush cache again after disabling
 	 * exported object. The second flush should be much faster.
 	*/
-	if (flush)
+	if (flush && ocf_cache_is_running(cache))
 		status = _cache_flush_with_lock(cache);
 	if (status)
 		goto put;
@@ -2494,16 +2547,21 @@ int cache_mngt_exit_instance(const char *cache_name, size_t name_len, int flush)
 	status = kcas_cache_destroy_all_core_exported_objects(cache);
 	if (status != 0) {
 		printk(KERN_WARNING
-			"Failed to remove all cached devices\n");
+				"Failed to remove all cached devices\n");
+		goto stop_thread;
+	}
+	status = kcas_cache_destroy_exported_object(cache);
+	if (status != 0) {
+		printk(KERN_WARNING
+				"Failed to remove cache exported object\n");
 		goto stop_thread;
 	}
 
 	/* Flush cache again. This time we don't allow interruption. */
-	if (flush)
+	if (flush && ocf_cache_is_running(cache))
 		flush_status = _cache_mngt_cache_flush_uninterruptible(cache);
 	context->flush_status = flush_status;
 
-
 	if (flush && !flush_status)
 		BUG_ON(ocf_mngt_cache_is_dirty(cache));
 

modules/include/cas_ioctl_codes.h

@@ -36,6 +36,7 @@
 
 #define CACHE_INIT_NEW	0 /**< initialize new metadata from fresh start */
 #define CACHE_INIT_LOAD	1 /**< load existing metadata */
+#define CACHE_INIT_BIND	2 /**< bind existing metadata */
 
 struct kcas_start_cache {
 	/**

ocf

@@ -1 +1 @@
-Subproject commit 865d29d0cb93a71ce37a8410914c35005aa6ed54
+Subproject commit 886c8d4e31e160f36d5ca3d0698a79811c8c0eca