path: root/net/switchdev/switchdev.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * net/switchdev/switchdev.c - Switch device API
 * Copyright (c) 2014-2015 Jiri Pirko <jiri@resnulli.us>
 * Copyright (c) 2014-2015 Scott Feldman <sfeldma@gmail.com>
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if_bridge.h>
#include <linux/list.h>
#include <linux/workqueue.h>
#include <linux/if_vlan.h>
#include <linux/rtnetlink.h>
#include <net/switchdev.h>

static bool switchdev_obj_eq(const struct switchdev_obj *a,
			     const struct switchdev_obj *b)
{
	const struct switchdev_obj_port_vlan *va, *vb;
	const struct switchdev_obj_port_mdb *ma, *mb;

	if (a->id != b->id || a->orig_dev != b->orig_dev)
		return false;

	switch (a->id) {
	case SWITCHDEV_OBJ_ID_PORT_VLAN:
		va = SWITCHDEV_OBJ_PORT_VLAN(a);
		vb = SWITCHDEV_OBJ_PORT_VLAN(b);
		return va->flags == vb->flags &&
			va->vid == vb->vid &&
			va->changed == vb->changed;
	case SWITCHDEV_OBJ_ID_PORT_MDB:
	case SWITCHDEV_OBJ_ID_HOST_MDB:
		ma = SWITCHDEV_OBJ_PORT_MDB(a);
		mb = SWITCHDEV_OBJ_PORT_MDB(b);
		return ma->vid == mb->vid &&
			ether_addr_equal(ma->addr, mb->addr);
	default:
		break;
	}

	BUG();
}

static LIST_HEAD(deferred);
static DEFINE_SPINLOCK(deferred_lock);

typedef void switchdev_deferred_func_t(struct net_device *dev,
				       const void *data);

struct switchdev_deferred_item {
	struct list_head list;
	struct net_device *dev;
	netdevice_tracker dev_tracker;
	switchdev_deferred_func_t *func;
	unsigned long data[];
};

static struct switchdev_deferred_item *switchdev_deferred_dequeue(void)
{
	struct switchdev_deferred_item *dfitem;

	spin_lock_bh(&deferred_lock);
	if (list_empty(&deferred)) {
		dfitem = NULL;
		goto unlock;
	}
	dfitem = list_first_entry(&deferred,
				  struct switchdev_deferred_item, list);
	list_del(&dfitem->list);
unlock:
	spin_unlock_bh(&deferred_lock);
	return dfitem;
}

/**
 *	switchdev_deferred_process - Process ops in deferred queue
 *
 *	Called to flush the ops currently queued in deferred ops queue.
 *	rtnl_lock must be held.
 */
void switchdev_deferred_process(void)
{
	struct switchdev_deferred_item *dfitem;

	ASSERT_RTNL();

	while ((dfitem = switchdev_deferred_dequeue())) {
		dfitem->func(dfitem->dev, dfitem->data);
		netdev_put(dfitem->dev, &dfitem->dev_tracker);
		kfree(dfitem);
	}
}
EXPORT_SYMBOL_GPL(switchdev_deferred_process);

static void switchdev_deferred_process_work(struct work_struct *work)
{
	rtnl_lock();
	switchdev_deferred_process();
	rtnl_unlock();
}

static DECLARE_WORK(deferred_process_work, switchdev_deferred_process_work);

static int switchdev_deferred_enqueue(struct net_device *dev,
				      const void *data, size_t data_len,
				      switchdev_deferred_func_t *func)
{
	struct switchdev_deferred_item *dfitem;

	dfitem = kmalloc(struct_size(dfitem, data, data_len), GFP_ATOMIC);
	if (!dfitem)
		return -ENOMEM;
	dfitem->dev = dev;
	dfitem->func = func;
	memcpy(dfitem->data, data, data_len);
	netdev_hold(dev, &dfitem->dev_tracker, GFP_ATOMIC);
	spin_lock_bh(&deferred_lock);
	list_add_tail(&dfitem->list, &deferred);
	spin_unlock_bh(&deferred_lock);
	schedule_work(&deferred_process_work);
	return 0;
}

static int switchdev_port_attr_notify(enum switchdev_notifier_type nt,
				      struct net_device *dev,
				      const struct switchdev_attr *attr,
				      struct netlink_ext_ack *extack)
{
	int err;
	int rc;

	struct switchdev_notifier_port_attr_info attr_info = {
		.attr = attr,
		.handled = false,
	};

	rc = call_switchdev_blocking_notifiers(nt, dev,
					       &attr_info.info, extack);
	err = notifier_to_errno(rc);
	if (err) {
		WARN_ON(!attr_info.handled);
		return err;
	}

	if (!attr_info.handled)
		return -EOPNOTSUPP;

	return 0;
}

static int switchdev_port_attr_set_now(struct net_device *dev,
				       const struct switchdev_attr *attr,
				       struct netlink_ext_ack *extack)
{
	return switchdev_port_attr_notify(SWITCHDEV_PORT_ATTR_SET, dev, attr,
					  extack);
}

static void switchdev_port_attr_set_deferred(struct net_device *dev,
					     const void *data)
{
	const struct switchdev_attr *attr = data;
	int err;

	err = switchdev_port_attr_set_now(dev, attr, NULL);
	if (err && err != -EOPNOTSUPP)
		netdev_err(dev, "failed (err=%d) to set attribute (id=%d)\n",
			   err, attr->id);
	if (attr->complete)
		attr->complete(dev, err, attr->complete_priv);
}

static int switchdev_port_attr_set_defer(struct net_device *d