static ssize_t do_id_store()

in bus.c [64:105]

• 39 lines of code
• 10 McCabe index (conditional complexity)

static ssize_t do_id_store(struct device_driver *drv, const char *buf,
		size_t count, enum id_action action)
{
	struct dax_device_driver *dax_drv = to_dax_drv(drv);
	unsigned int region_id, id;
	char devname[DAX_NAME_LEN];
	struct dax_id *dax_id;
	ssize_t rc = count;
	int fields;

	fields = sscanf(buf, "dax%d.%d", &region_id, &id);
	if (fields != 2)
		return -EINVAL;
	sprintf(devname, "dax%d.%d", region_id, id);
	if (!sysfs_streq(buf, devname))
		return -EINVAL;

	mutex_lock(&dax_bus_lock);
	dax_id = __dax_match_id(dax_drv, buf);
	if (!dax_id) {
		if (action == ID_ADD) {
			dax_id = kzalloc(sizeof(*dax_id), GFP_KERNEL);
			if (dax_id) {
				strncpy(dax_id->dev_name, buf, DAX_NAME_LEN);
				list_add(&dax_id->list, &dax_drv->ids);
			} else
				rc = -ENOMEM;
		}
	} else if (action == ID_REMOVE) {
		list_del(&dax_id->list);
		kfree(dax_id);
	}
	mutex_unlock(&dax_bus_lock);

	if (rc < 0)
		return rc;
	if (action == ID_ADD)
		rc = driver_attach(drv);
	if (rc)
		return rc;
	return count;
}