static ssize_t nvm_authenticate_sysfs()

in switch.c [1779:1838]

• 49 lines of code
• 13 McCabe index (conditional complexity)

static ssize_t nvm_authenticate_sysfs(struct device *dev, const char *buf,
				      bool disconnect)
{
	struct tb_switch *sw = tb_to_switch(dev);
	int val, ret;

	pm_runtime_get_sync(&sw->dev);

	if (!mutex_trylock(&sw->tb->lock)) {
		ret = restart_syscall();
		goto exit_rpm;
	}

	/* If NVMem devices are not yet added */
	if (!sw->nvm) {
		ret = -EAGAIN;
		goto exit_unlock;
	}

	ret = kstrtoint(buf, 10, &val);
	if (ret)
		goto exit_unlock;

	/* Always clear the authentication status */
	nvm_clear_auth_status(sw);

	if (val > 0) {
		if (val == AUTHENTICATE_ONLY) {
			if (disconnect)
				ret = -EINVAL;
			else
				ret = nvm_authenticate(sw, true);
		} else {
			if (!sw->nvm->flushed) {
				if (!sw->nvm->buf) {
					ret = -EINVAL;
					goto exit_unlock;
				}

				ret = nvm_validate_and_write(sw);
				if (ret || val == WRITE_ONLY)
					goto exit_unlock;
			}
			if (val == WRITE_AND_AUTHENTICATE) {
				if (disconnect)
					ret = tb_lc_force_power(sw);
				else
					ret = nvm_authenticate(sw, false);
			}
		}
	}

exit_unlock:
	mutex_unlock(&sw->tb->lock);
exit_rpm:
	pm_runtime_mark_last_busy(&sw->dev);
	pm_runtime_put_autosuspend(&sw->dev);

	return ret;
}