linux/drivers/net/ethernet/sfc/efx_common.c

// SPDX-License-Identifier: GPL-2.0-only
/****************************************************************************
 * Driver for Solarflare network controllers and boards
 * Copyright 2018 Solarflare Communications Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation, incorporated herein by reference.
 */

#include "net_driver.h"
#include <linux/module.h>
#include <linux/netdevice.h>
#include "efx_common.h"
#include "efx_channels.h"
#include "efx.h"
#include "mcdi.h"
#include "selftest.h"
#include "rx_common.h"
#include "tx_common.h"
#include "nic.h"
#include "io.h"
#include "mcdi_pcol.h"

/* Reset workqueue. If any NIC has a hardware failure then a reset will be
 * queued onto this work queue. This is not a per-nic work queue, because
 * efx_reset_work() acquires the rtnl lock, so resets are naturally serialised.
 */
static struct workqueue_struct *reset_workqueue;

int efx_create_reset_workqueue(void)
{
	reset_workqueue = create_singlethread_workqueue("sfc_reset");
	if (!reset_workqueue) {
		printk(KERN_ERR "Failed to create reset workqueue\n");
		return -ENOMEM;
	}

	return 0;
}

void efx_queue_reset_work(struct efx_nic *efx)
{
	queue_work(reset_workqueue, &efx->reset_work);
}

void efx_flush_reset_workqueue(struct efx_nic *efx)
{
	cancel_work_sync(&efx->reset_work);
}

void efx_destroy_reset_workqueue(void)
{
	if (reset_workqueue) {
		destroy_workqueue(reset_workqueue);
		reset_workqueue = NULL;
	}
}

/* We assume that efx->type->reconfigure_mac will always try to sync RX
 * filters and therefore needs to read-lock the filter table against freeing
 */
void efx_mac_reconfigure(struct efx_nic *efx)
{
	down_read(&efx->filter_sem);
	efx->type->reconfigure_mac(efx);
	up_read(&efx->filter_sem);
}

/* This ensures that the kernel is kept informed (via
 * netif_carrier_on/off) of the link status, and also maintains the
 * link status's stop on the port's TX queue.
 */
void efx_link_status_changed(struct efx_nic *efx)
{
	struct efx_link_state *link_state = &efx->link_state;

	/* SFC Bug 5356: A net_dev notifier is registered, so we must ensure
	 * that no events are triggered between unregister_netdev() and the
	 * driver unloading. A more general condition is that NETDEV_CHANGE
	 * can only be generated between NETDEV_UP and NETDEV_DOWN
	 */
	if (!netif_running(efx->net_dev))
		return;

	if (link_state->up != netif_carrier_ok(efx->net_dev)) {
		efx->n_link_state_changes++;

		if (link_state->up)
			netif_carrier_on(efx->net_dev);
		else
			netif_carrier_off(efx->net_dev);
	}

	/* Status message for kernel log */
	if (link_state->up)
		netif_info(efx, link, efx->net_dev,
			   "link up at %uMbps %s-duplex (MTU %d)\n",
			   link_state->speed, link_state->fd ? "full" : "half",
			   efx->net_dev->mtu);
	else
		netif_info(efx, link, efx->net_dev, "link down\n");
}