Ensure that cache name is set and unique

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

inc/ocf_err.h

@@ -57,10 +57,10 @@ typedef enum {
 	/** Start cache failure */
 	OCF_ERR_START_CACHE_FAIL,
 
-	/** Cache ID does not exist */
+	/** Cache ID/name does not exist */
 	OCF_ERR_CACHE_NOT_EXIST,
 
-	/** Cache ID already exists */
+	/** Cache ID/name already exists */
 	OCF_ERR_CACHE_EXIST,
 
 	/** Too many core devices in cache */

inc/ocf_mngt.h

@@ -101,6 +101,22 @@ uint32_t ocf_mngt_cache_get_count(ocf_ctx_t ctx);
  */
 int ocf_mngt_cache_get_by_id(ocf_ctx_t ctx, ocf_cache_id_t id, ocf_cache_t *cache);
 
+/**
+ * @brief Get OCF cache by name
+ *
+ * @note This function on success also increases reference counter
+ *       in given cache
+ *
+ * @param[in] ctx OCF context
+ * @param[in] name OCF cache name
+ * @param[out] cache OCF cache handle
+ *
+ * @retval 0 Get cache successfully
+ * @retval -OCF_ERR_CACHE_NOT_EXIST Cache with given name doesn't exist
+ */
+int ocf_mngt_cache_get_by_name(ocf_ctx_t ctx, const char* name,
+		ocf_cache_t *cache);
+
 /**
  * @brief Increment reference counter of cache
  *
@@ -247,8 +263,7 @@ struct ocf_mngt_cache_config {
 	ocf_cache_id_t id;
 
 	/**
-	 * @brief Cache name. In case of being NULL, cache id is stringified to
-	 *		cache name
+	 * @brief Cache name
 	 */
 	const char *name;
 
@@ -309,13 +324,15 @@ struct ocf_mngt_cache_config {
 /**
  * @brief Initialize core config to default values
  *
+ * @note This function doesn't initialize name field which has no default
+ *       value and is required to be set by user.
+ *
  * @param[in] cfg Cache config stucture
  */
 static inline void ocf_mngt_cache_config_set_default(
 		struct ocf_mngt_cache_config *cfg)
 {
 	cfg->id = OCF_CACHE_ID_INVALID;
-	cfg->name = NULL;
 	cfg->cache_mode = ocf_cache_mode_default;
 	cfg->eviction_policy = ocf_eviction_default;
 	cfg->promotion_policy = ocf_promotion_default;

src/mngt/ocf_mngt_cache.c

@@ -726,18 +726,20 @@ static int _ocf_mngt_init_prepare_cache(struct ocf_cache_mngt_init_params *param
 		}
 	}
 
-	if (cfg->name) {
-		ret = env_strncpy(cache_name, sizeof(cache_name) - 1,
-				cfg->name, sizeof(cache_name) - 1);
-		if (ret)
-			goto out;
-	} else {
-		ret = snprintf(cache_name, sizeof(cache_name),
-				"cache%hu", param->id);
-		if (ret < 0)
+	/* Check if cache with specified name exists */
+	ret = ocf_mngt_cache_get_by_name(param->ctx, cfg->name, &cache);
+	if (!ret) {
+		ocf_mngt_cache_put(cache);
+		/* Cache already exist */
+		ret = -OCF_ERR_CACHE_EXIST;
 		goto out;
 	}
 
+	ret = env_strncpy(cache_name, sizeof(cache_name),
+			cfg->name, sizeof(cache_name));
+	if (ret)
+		goto out;
+
 	ocf_log(param->ctx, log_info, "Inserting cache %s\n", cache_name);
 
 	ret = _ocf_mngt_init_new_cache(param);
@@ -1643,6 +1645,9 @@ static int _ocf_mngt_cache_validate_cfg(struct ocf_mngt_cache_config *cfg)
 	if (cfg->id > OCF_CACHE_ID_MAX)
 		return -OCF_ERR_INVAL;
 
+	if (!cfg->name)
+		return -OCF_ERR_INVAL;
+
 	if (!ocf_cache_mode_is_valid(cfg->cache_mode))
 		return -OCF_ERR_INVALID_CACHE_MODE;
 

src/mngt/ocf_mngt_common.c

@@ -183,6 +183,44 @@ int ocf_mngt_cache_get_by_id(ocf_ctx_t ocf_ctx, ocf_cache_id_t id, ocf_cache_t *
 	return error;
 }
 
+int ocf_mngt_cache_get_by_name(ocf_ctx_t ctx, const char *name,
+		ocf_cache_t *cache)
+{
+	struct ocf_cache *instance = NULL;
+	struct ocf_cache *iter = NULL;
+
+	OCF_CHECK_NULL(ctx);
+	OCF_CHECK_NULL(cache);
+
+	/* Lock caches list */
+	env_rmutex_lock(&ctx->lock);
+
+	list_for_each_entry(iter, &ctx->caches, list) {
+		if (!env_strncmp(ocf_cache_get_name(iter), name,
+				OCF_CACHE_NAME_SIZE)) {
+			instance = iter;
+			break;
+		}
+	}
+
+	if (instance) {
+		/* if cache is either fully initialized or during recovery */
+		if (!ocf_refcnt_inc(&instance->refcnt.cache)) {
+			/* Cache not initialized yet */
+			instance = NULL;
+		}
+	}
+
+	env_rmutex_unlock(&ctx->lock);
+
+	if (!instance)
+		return -OCF_ERR_CACHE_NOT_EXIST;
+
+	*cache = instance;
+
+	return 0;
+}
+
 typedef void (*ocf_lock_fn_t)(ocf_async_lock_waiter_t waiter);
 
 typedef int (*ocf_trylock_fn_t)(ocf_async_lock_t lock);