static int gve_adminq_issue_cmd()

in google/gve/gve_adminq.c [473:570]

• 85 lines of code
• 23 McCabe index (conditional complexity)

static int gve_adminq_issue_cmd(struct gve_priv *priv,
				union gve_adminq_command *cmd_orig)
{
	union gve_adminq_command *cmd;
	u32 opcode;
	u32 tail;

	tail = ioread32be(&priv->reg_bar0->adminq_event_counter);

	// Check if next command will overflow the buffer.
	if (((priv->adminq_prod_cnt + 1) & priv->adminq_mask) ==
	    (tail & priv->adminq_mask)) {
		int err;

		// Flush existing commands to make room.
		err = gve_adminq_kick_and_wait(priv);
		if (err)
			return err;

		// Retry.
		tail = ioread32be(&priv->reg_bar0->adminq_event_counter);
		if (((priv->adminq_prod_cnt + 1) & priv->adminq_mask) ==
		    (tail & priv->adminq_mask)) {
			// This should never happen. We just flushed the
			// command queue so there should be enough space.
			return -ENOMEM;
		}
	}

	cmd = &priv->adminq[priv->adminq_prod_cnt & priv->adminq_mask];
	priv->adminq_prod_cnt++;

	memcpy(cmd, cmd_orig, sizeof(*cmd_orig));
	opcode = be32_to_cpu(READ_ONCE(cmd->opcode));
	if (opcode == GVE_ADMINQ_EXTENDED_COMMAND)
		opcode = be32_to_cpu(cmd->extended_command.inner_opcode);

	switch (opcode) {
	case GVE_ADMINQ_DESCRIBE_DEVICE:
		priv->adminq_describe_device_cnt++;
		break;
	case GVE_ADMINQ_CONFIGURE_DEVICE_RESOURCES:
		priv->adminq_cfg_device_resources_cnt++;
		break;
	case GVE_ADMINQ_REGISTER_PAGE_LIST:
		priv->adminq_register_page_list_cnt++;
		break;
	case GVE_ADMINQ_UNREGISTER_PAGE_LIST:
		priv->adminq_unregister_page_list_cnt++;
		break;
	case GVE_ADMINQ_CREATE_TX_QUEUE:
		priv->adminq_create_tx_queue_cnt++;
		break;
	case GVE_ADMINQ_CREATE_RX_QUEUE:
		priv->adminq_create_rx_queue_cnt++;
		break;
	case GVE_ADMINQ_DESTROY_TX_QUEUE:
		priv->adminq_destroy_tx_queue_cnt++;
		break;
	case GVE_ADMINQ_DESTROY_RX_QUEUE:
		priv->adminq_destroy_rx_queue_cnt++;
		break;
	case GVE_ADMINQ_DECONFIGURE_DEVICE_RESOURCES:
		priv->adminq_dcfg_device_resources_cnt++;
		break;
	case GVE_ADMINQ_SET_DRIVER_PARAMETER:
		priv->adminq_set_driver_parameter_cnt++;
		break;
	case GVE_ADMINQ_REPORT_STATS:
		priv->adminq_report_stats_cnt++;
		break;
	case GVE_ADMINQ_REPORT_LINK_SPEED:
		priv->adminq_report_link_speed_cnt++;
		break;
	case GVE_ADMINQ_GET_PTYPE_MAP:
		priv->adminq_get_ptype_map_cnt++;
		break;
	case GVE_ADMINQ_VERIFY_DRIVER_COMPATIBILITY:
		priv->adminq_verify_driver_compatibility_cnt++;
		break;
	case GVE_ADMINQ_QUERY_FLOW_RULES:
		priv->adminq_query_flow_rules_cnt++;
		break;
	case GVE_ADMINQ_CONFIGURE_FLOW_RULE:
		priv->adminq_cfg_flow_rule_cnt++;
		break;
	case GVE_ADMINQ_CONFIGURE_RSS:
		priv->adminq_cfg_rss_cnt++;
		break;
	case GVE_ADMINQ_QUERY_RSS:
		priv->adminq_query_rss_cnt++;
		break;
	default:
		dev_err(&priv->pdev->dev, "unknown AQ command opcode %d\n", opcode);
	}

	return 0;
}