Purge cache command

Purge invalidates all cache lines. It is very usefull feature for tests.

Calling purge is possbile with casadm `--script` swtich.

Signed-off-by: Michal Mielewczyk <michal.mielewczyk@intel.com>

casadm/cas_lib.c

@@ -1915,6 +1915,29 @@ int core_pool_remove(const char *core_device)
 	return SUCCESS;
 }
 
+int purge_cache(unsigned int cache_id)
+{
+	int fd = 0;
+	struct kcas_flush_cache cmd;
+
+	fd = open_ctrl_device();
+	if (fd == -1)
+		return FAILURE;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.cache_id = cache_id;
+	/* synchronous flag */
+	if (run_ioctl_interruptible(fd, KCAS_IOCTL_PURGE_CACHE, &cmd, "Purging cache",
+			cache_id, OCF_CORE_ID_INVALID) < 0) {
+		close(fd);
+		print_err(cmd.ext_err_code);
+		return FAILURE;
+	}
+
+	close(fd);
+	return SUCCESS;
+}
+
 #define DIRTY_FLUSHING_WARNING "You have interrupted flushing of cache dirty data. CAS continues to operate\nnormally and dirty data that remains on cache device will be flushed by cleaning thread.\n"
 int flush_cache(unsigned int cache_id)
 {

casadm/cas_lib.h

@@ -220,6 +220,8 @@ int get_core_pool_count(int fd);
 
 int reset_counters(unsigned int cache_id, unsigned int core_id);
 
+int purge_cache(unsigned int cache_id);
+
 int flush_cache(unsigned int cache_id);
 int flush_core(unsigned int cache_id, unsigned int core_id);
 

casadm/cas_main.c

@@ -1419,6 +1419,7 @@ enum {
 
 	script_cmd_add_core,
 	script_cmd_remove_core,
+	script_cmd_purge_cache,
 
 	script_cmd_max_id,
 
@@ -1477,6 +1478,14 @@ static cli_option script_params_options[] = {
 			| (1 << script_opt_core_id),
 		.flags = CLI_COMMAND_HIDDEN,
 	},
+	[script_cmd_purge_cache] = {
+		.short_name = 0,
+		.long_name = "purge-cache",
+		.args_count = 0,
+		.arg = NULL,
+		.priv = (1 << script_opt_cache_id),
+		.flags = CLI_COMMAND_HIDDEN,
+	},
 	[script_opt_cache_device] = {
 		.short_name = 0,
 		.long_name = "cache-device",
@@ -1491,7 +1500,8 @@ static cli_option script_params_options[] = {
 		.args_count = 1,
 		.arg = "ID",
 		.priv = (1 << script_cmd_remove_core)
-			| (1 << script_cmd_add_core),
+			| (1 << script_cmd_add_core)
+			| (1 << script_cmd_purge_cache),
 		.flags = (CLI_OPTION_RANGE_INT | CLI_OPTION_HIDDEN),
 		.min_value = OCF_CACHE_ID_MIN,
 		.max_value = OCF_CACHE_ID_MAX,
@@ -1658,6 +1668,8 @@ int script_handle() {
 			command_args_values.detach,
 			command_args_values.no_flush
 			);
+	case script_cmd_purge_cache:
+		return purge_cache(command_args_values.cache_id);
 	}
 
 	return FAILURE;