net_kern.c

来自「linux 内核源代码」· C语言 代码 · 共 925 行 · 第 1/2 页

		  .remove 		= transport->user->remove,
		  .read 		= transport->kern->read,
		  .write 		= transport->kern->write,
		  .add_address 		= transport->user->add_address,
		  .delete_address  	= transport->user->delete_address });

	init_timer(&lp->tl);
	spin_lock_init(&lp->lock);
	lp->tl.function = uml_net_user_timer_expire;
	memcpy(lp->mac, device->mac, sizeof(lp->mac));

	if ((transport->user->init != NULL) &&
	    ((*transport->user->init)(&lp->user, dev) != 0))
		goto out_unregister;

	set_ether_mac(dev, device->mac);
	dev->mtu = transport->user->mtu;
	dev->open = uml_net_open;
	dev->hard_start_xmit = uml_net_start_xmit;
	dev->stop = uml_net_close;
	dev->get_stats = uml_net_get_stats;
	dev->set_multicast_list = uml_net_set_multicast_list;
	dev->tx_timeout = uml_net_tx_timeout;
	dev->set_mac_address = uml_net_set_mac;
	dev->change_mtu = uml_net_change_mtu;
	dev->ethtool_ops = &uml_net_ethtool_ops;
	dev->watchdog_timeo = (HZ >> 1);
	dev->irq = UM_ETH_IRQ;

	err = update_drop_skb(lp->max_packet);
	if (err)
		goto out_undo_user_init;

	rtnl_lock();
	err = register_netdevice(dev);
	rtnl_unlock();
	if (err)
		goto out_undo_user_init;

	spin_lock(&devices_lock);
	list_add(&device->list, &devices);
	spin_unlock(&devices_lock);

	return;

out_undo_user_init:
	if (transport->user->remove != NULL)
		(*transport->user->remove)(&lp->user);
out_unregister:
	platform_device_unregister(&device->pdev);
	return; /* platform_device_unregister frees dev and device */
out_free_netdev:
	free_netdev(dev);
out_free_device:
	kfree(device);
}

static struct uml_net *find_device(int n)
{
	struct uml_net *device;
	struct list_head *ele;

	spin_lock(&devices_lock);
	list_for_each(ele, &devices) {
		device = list_entry(ele, struct uml_net, list);
		if (device->index == n)
			goto out;
	}
	device = NULL;
 out:
	spin_unlock(&devices_lock);
	return device;
}

static int eth_parse(char *str, int *index_out, char **str_out,
		     char **error_out)
{
	char *end;
	int n, err = -EINVAL;;

	n = simple_strtoul(str, &end, 0);
	if (end == str) {
		*error_out = "Bad device number";
		return err;
	}

	str = end;
	if (*str != '=') {
		*error_out = "Expected '=' after device number";
		return err;
	}

	str++;
	if (find_device(n)) {
		*error_out = "Device already configured";
		return err;
	}

	*index_out = n;
	*str_out = str;
	return 0;
}

struct eth_init {
	struct list_head list;
	char *init;
	int index;
};

static DEFINE_SPINLOCK(transports_lock);
static LIST_HEAD(transports);

/* Filled in during early boot */
static LIST_HEAD(eth_cmd_line);

static int check_transport(struct transport *transport, char *eth, int n,
			   void **init_out, char **mac_out)
{
	int len;

	len = strlen(transport->name);
	if (strncmp(eth, transport->name, len))
		return 0;

	eth += len;
	if (*eth == ',')
		eth++;
	else if (*eth != '\0')
		return 0;

	*init_out = kmalloc(transport->setup_size, GFP_KERNEL);
	if (*init_out == NULL)
		return 1;

	if (!transport->setup(eth, mac_out, *init_out)) {
		kfree(*init_out);
		*init_out = NULL;
	}
	return 1;
}

void register_transport(struct transport *new)
{
	struct list_head *ele, *next;
	struct eth_init *eth;
	void *init;
	char *mac = NULL;
	int match;

	spin_lock(&transports_lock);
	BUG_ON(!list_empty(&new->list));
	list_add(&new->list, &transports);
	spin_unlock(&transports_lock);

	list_for_each_safe(ele, next, &eth_cmd_line) {
		eth = list_entry(ele, struct eth_init, list);
		match = check_transport(new, eth->init, eth->index, &init,
					&mac);
		if (!match)
			continue;
		else if (init != NULL) {
			eth_configure(eth->index, init, mac, new);
			kfree(init);
		}
		list_del(&eth->list);
	}
}

static int eth_setup_common(char *str, int index)
{
	struct list_head *ele;
	struct transport *transport;
	void *init;
	char *mac = NULL;
	int found = 0;

	spin_lock(&transports_lock);
	list_for_each(ele, &transports) {
		transport = list_entry(ele, struct transport, list);
	        if (!check_transport(transport, str, index, &init, &mac))
			continue;
		if (init != NULL) {
			eth_configure(index, init, mac, transport);
			kfree(init);
		}
		found = 1;
		break;
	}

	spin_unlock(&transports_lock);
	return found;
}

static int __init eth_setup(char *str)
{
	struct eth_init *new;
	char *error;
	int n, err;

	err = eth_parse(str, &n, &str, &error);
	if (err) {
		printk(KERN_ERR "eth_setup - Couldn't parse '%s' : %s\n",
		       str, error);
		return 1;
	}

	new = alloc_bootmem(sizeof(*new));
	if (new == NULL) {
		printk(KERN_ERR "eth_init : alloc_bootmem failed\n");
		return 1;
	}

	INIT_LIST_HEAD(&new->list);
	new->index = n;
	new->init = str;

	list_add_tail(&new->list, &eth_cmd_line);
	return 1;
}

__setup("eth", eth_setup);
__uml_help(eth_setup,
"eth[0-9]+=<transport>,<options>\n"
"    Configure a network device.\n\n"
);

static int net_config(char *str, char **error_out)
{
	int n, err;

	err = eth_parse(str, &n, &str, error_out);
	if (err)
		return err;

	/* This string is broken up and the pieces used by the underlying
	 * driver.  So, it is freed only if eth_setup_common fails.
	 */
	str = kstrdup(str, GFP_KERNEL);
	if (str == NULL) {
	        *error_out = "net_config failed to strdup string";
		return -ENOMEM;
	}
	err = !eth_setup_common(str, n);
	if (err)
		kfree(str);
	return err;
}

static int net_id(char **str, int *start_out, int *end_out)
{
	char *end;
	int n;

	n = simple_strtoul(*str, &end, 0);
	if ((*end != '\0') || (end == *str))
		return -1;

	*start_out = n;
	*end_out = n;
	*str = end;
	return n;
}

static int net_remove(int n, char **error_out)
{
	struct uml_net *device;
	struct net_device *dev;
	struct uml_net_private *lp;

	device = find_device(n);
	if (device == NULL)
		return -ENODEV;

	dev = device->dev;
	lp = dev->priv;
	if (lp->fd > 0)
		return -EBUSY;
	unregister_netdev(dev);
	platform_device_unregister(&device->pdev);

	return 0;
}

static struct mc_device net_mc = {
	.list		= LIST_HEAD_INIT(net_mc.list),
	.name		= "eth",
	.config		= net_config,
	.get_config	= NULL,
	.id		= net_id,
	.remove		= net_remove,
};

#ifdef CONFIG_INET
static int uml_inetaddr_event(struct notifier_block *this, unsigned long event,
			      void *ptr)
{
	struct in_ifaddr *ifa = ptr;
	struct net_device *dev = ifa->ifa_dev->dev;
	struct uml_net_private *lp;
	void (*proc)(unsigned char *, unsigned char *, void *);
	unsigned char addr_buf[4], netmask_buf[4];

	if (dev->open != uml_net_open)
		return NOTIFY_DONE;

	lp = dev->priv;

	proc = NULL;
	switch (event) {
	case NETDEV_UP:
		proc = lp->add_address;
		break;
	case NETDEV_DOWN:
		proc = lp->delete_address;
		break;
	}
	if (proc != NULL) {
		memcpy(addr_buf, &ifa->ifa_address, sizeof(addr_buf));
		memcpy(netmask_buf, &ifa->ifa_mask, sizeof(netmask_buf));
		(*proc)(addr_buf, netmask_buf, &lp->user);
	}
	return NOTIFY_DONE;
}

/* uml_net_init shouldn't be called twice on two CPUs at the same time */
struct notifier_block uml_inetaddr_notifier = {
	.notifier_call		= uml_inetaddr_event,
};

static void inet_register(void)
{
	struct list_head *ele;
	struct uml_net_private *lp;
	struct in_device *ip;
	struct in_ifaddr *in;

	register_inetaddr_notifier(&uml_inetaddr_notifier);

	/* Devices may have been opened already, so the uml_inetaddr_notifier
	 * didn't get a chance to run for them.  This fakes it so that
	 * addresses which have already been set up get handled properly.
	 */
	spin_lock(&opened_lock);
	list_for_each(ele, &opened) {
		lp = list_entry(ele, struct uml_net_private, list);
		ip = lp->dev->ip_ptr;
		if (ip == NULL)
			continue;
		in = ip->ifa_list;
		while (in != NULL) {
			uml_inetaddr_event(NULL, NETDEV_UP, in);
			in = in->ifa_next;
		}
	}
	spin_unlock(&opened_lock);
}
#else
static inline void inet_register(void)
{
}
#endif

static int uml_net_init(void)
{
	mconsole_register_dev(&net_mc);
	inet_register();
	return 0;
}

__initcall(uml_net_init);

static void close_devices(void)
{
	struct list_head *ele;
	struct uml_net_private *lp;

	spin_lock(&opened_lock);
	list_for_each(ele, &opened) {
		lp = list_entry(ele, struct uml_net_private, list);
		free_irq(lp->dev->irq, lp->dev);
		if ((lp->close != NULL) && (lp->fd >= 0))
			(*lp->close)(lp->fd, &lp->user);
		if (lp->remove != NULL)
			(*lp->remove)(&lp->user);
	}
	spin_unlock(&opened_lock);
}

__uml_exitcall(close_devices);

void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *,
					void *),
		    void *arg)
{
	struct net_device *dev = d;
	struct in_device *ip = dev->ip_ptr;
	struct in_ifaddr *in;
	unsigned char address[4], netmask[4];

	if (ip == NULL) return;
	in = ip->ifa_list;
	while (in != NULL) {
		memcpy(address, &in->ifa_address, sizeof(address));
		memcpy(netmask, &in->ifa_mask, sizeof(netmask));
		(*cb)(address, netmask, arg);
		in = in->ifa_next;
	}
}

int dev_netmask(void *d, void *m)
{
	struct net_device *dev = d;
	struct in_device *ip = dev->ip_ptr;
	struct in_ifaddr *in;
	__be32 *mask_out = m;

	if (ip == NULL)
		return 1;

	in = ip->ifa_list;
	if (in == NULL)
		return 1;

	*mask_out = in->ifa_mask;
	return 0;
}

void *get_output_buffer(int *len_out)
{
	void *ret;

	ret = (void *) __get_free_pages(GFP_KERNEL, 0);
	if (ret) *len_out = PAGE_SIZE;
	else *len_out = 0;
	return ret;
}

void free_output_buffer(void *buffer)
{
	free_pages((unsigned long) buffer, 0);
}

int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out,
		     char **gate_addr)
{
	char *remain;

	remain = split_if_spec(str, dev_name, mac_out, gate_addr, NULL);
	if (remain != NULL) {
		printk(KERN_ERR "tap_setup_common - Extra garbage on "
		       "specification : '%s'\n", remain);
		return 1;
	}

	return 0;
}

unsigned short eth_protocol(struct sk_buff *skb)
{
	return eth_type_trans(skb, skb->dev);
}