runner: Add Media Change

This patch series will add media change that is
triggered via targetcli without involving the kernel

Based on patches my Bryant G. Ly.

Signed-off-by: Bryant G. Ly <[email protected]>
Signed-off-by: Mike Christie <[email protected]>

file_optical.c

@@ -1559,6 +1559,7 @@ static struct tcmur_handler fbo_handler = {
 	.subtype = "fbo",
 	.handle_cmd = fbo_handle_cmd,
 	.nr_threads = 1,
+	.medium_change_supp = 1,
 };
 
 /* Entry point must be named "handler_init". */

main.c

@@ -189,8 +189,62 @@ on_check_config(TCMUService1 *interface,
 	return TRUE;
 }
 
+static gboolean
+on_change_medium(TCMUService1 *interface,
+		 GDBusMethodInvocation *invocation,
+		 gchar *name,
+		 guint64 size,
+		 gchar *cfgstring,
+		 gpointer user_data)
+{
+	struct tcmulib_context *ctx = user_data;
+	struct tcmur_handler *rhandler;
+	struct tcmu_device *dev = NULL;
+	char *reason = NULL;
+	int ret = 0;
+
+	dev = tcmulib_lookup_dev_by_tcmu_name(ctx, name);
+	if (!dev) {
+		ret = ENODEV;
+		reason = "Device not found.";
+		goto exit;
+	}
+
+	rhandler = tcmu_get_runner_handler(dev);
+	if (!rhandler->medium_change_supp) {
+		ret = EOPNOTSUPP;
+		reason = "Handler does not support medium changes.";
+		goto exit;
+	}
+
+	tcmu_block_device(dev);
+	tcmu_flush_device(dev);
+
+	tcmu_set_cfgfs_ctrl_str(dev, "dev_config", cfgstring);
+	tcmu_update_num_lbas(dev, size);
+	tcmu_set_dev_size(dev);
+
+	ret = tcmu_reopen_dev(dev, false, 0);
+	if (ret == 0) {
+		reason = "success";
+	} else {
+		reason = strerror(ret);
+	}
+
+	tcmu_dev_set_pending_ua(dev, TCMUR_UA_DEV_MEDIUM_CHANGED);
+	tcmu_unblock_device(dev);
+
+exit:
+	g_dbus_method_invocation_return_value(invocation,
+		g_variant_new("(is)", ret, reason));
+
+	return TRUE;
+}
+
 static void
-dbus_export_handler(struct tcmur_handler *handler, GCallback check_config)
+dbus_export_handler(struct tcmulib_context *tcmulib_context,
+		    struct tcmur_handler *handler, GCallback check_config,
+		    GCallback change_medium)
 {
 	GDBusObjectSkeleton *object;
 	char obj_name[128];
@@ -205,6 +259,10 @@ dbus_export_handler(struct tcmur_handler *handler, GCallback check_config)
 			 "handle-check-config",
 			 check_config,
 			 handler); /* user_data */
+	g_signal_connect(interface,
+			 "handle-change-medium",
+			 change_medium,
+			 tcmulib_context);
 	tcmuservice1_set_config_desc(interface, handler->cfg_desc);
 	g_dbus_object_manager_server_export(manager, G_DBUS_OBJECT_SKELETON(object));
 	g_object_unref(object);
@@ -216,12 +274,14 @@ static void dbus_bus_acquired(GDBusConnection *connection,
 {
 	struct tcmur_handler **handler;
 
-	tcmu_dbg("bus %s acquired\n", name);
+	tcmu_dbg("bus %s acquired %p\n", name, user_data);
 
 	manager = g_dbus_object_manager_server_new("/org/kernel/TCMUService1");
 
 	darray_foreach(handler, g_runner_handlers) {
-		dbus_export_handler(*handler, G_CALLBACK(on_check_config));
+		dbus_export_handler(user_data, *handler,
+				    G_CALLBACK(on_check_config),
+				    G_CALLBACK(on_change_medium));
 	}
 
 	g_dbus_object_manager_server_set_connection(manager, connection);
@@ -902,7 +962,7 @@ int main(int argc, char **argv)
 				dbus_bus_acquired,
 				dbus_name_acquired, // name acquired
 				dbus_name_lost, // name lost
-				NULL, // user data
+				tcmulib_context, // user data
 				NULL  // user date free func
 		);
 

tcmu-handler.xml

@@ -16,6 +16,13 @@ that the configstring is valid before the device has been created.
       <arg type="b" name="is_valid" direction="out"/>
       <arg type="s" name="message" direction="out"/>
     </method>
+    <method name="ChangeMedium">
+      <arg type="s" name="name" direction="in"/>
+      <arg type="t" name="size" direction="in"/>
+      <arg type="s" name="configstr" direction="in"/>
+      <arg type="i" name="ret" direction="out"/>
+      <arg type="s" name="message" direction="out"/>
+    </method>
   </interface>
   <interface name="org.kernel.TCMUService1.HandlerManager1">
     <method name="RegisterHandler">

tcmu-runner.h

@@ -59,6 +59,11 @@ struct tcmur_handler {
 
 	int (*reconfig)(struct tcmu_device *dev, struct tcmulib_cfg_info *cfg);
 
+	/*
+	 * True if handler supports medium changes via reopen calls.
+	 */
+	bool medium_change_supp;
+
 	/* Per-device added/removed callbacks */
 	int (*open)(struct tcmu_device *dev, bool reopen);
 	void (*close)(struct tcmu_device *dev);

tcmur_device.c

@@ -426,6 +426,10 @@ int tcmu_dev_handle_pending_ua(struct tcmu_device *dev, struct tcmulib_cmd *cmd)
 		/* Device capacity has changed */
 		tcmu_set_sense_data(cmd->sense_buf, UNIT_ATTENTION, 0x2A09);
 		break;
+	case TCMUR_UA_DEV_MEDIUM_CHANGED:
+		/* medium changed */
+		tcmu_set_sense_data(cmd->sense_buf, UNIT_ATTENTION, 0x2800);
+		break;
 	default:
 		tcmu_dev_err(dev, "Unhandled UA %d\n", ua);
 		goto unlock;

tcmur_device.h

@@ -22,6 +22,7 @@
 #define TCMUR_DEV_FLAG_STOPPED		(1 << 4)
 
 #define TCMUR_UA_DEV_SIZE_CHANGED	0
+#define TCMUR_UA_DEV_MEDIUM_CHANGED	1
 
 enum {
 	TMCUR_DEV_FAILOVER_ALL_ACTIVE,