1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
5 * James Leu (jleu@mindspring.net).
6 * Copyright (C) 2001 by various other people who didn't put their name here.
9 #include <linux/memblock.h>
10 #include <linux/etherdevice.h>
11 #include <linux/ethtool.h>
12 #include <linux/inetdevice.h>
13 #include <linux/init.h>
14 #include <linux/list.h>
15 #include <linux/netdevice.h>
16 #include <linux/platform_device.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/skbuff.h>
19 #include <linux/slab.h>
20 #include <linux/spinlock.h>
24 #include "mconsole_kern.h"
28 #define DRIVER_NAME "uml-netdev"
30 static DEFINE_SPINLOCK(opened_lock);
31 static LIST_HEAD(opened);
34 * The drop_skb is used when we can't allocate an skb. The
35 * packet is read into drop_skb in order to get the data off the
36 * connection to the host.
37 * It is reallocated whenever a maximum packet size is seen which is
38 * larger than any seen before. update_drop_skb is called from
39 * eth_configure when a new interface is added.
41 static DEFINE_SPINLOCK(drop_lock);
42 static struct sk_buff *drop_skb;
45 static int update_drop_skb(int max)
51 spin_lock_irqsave(&drop_lock, flags);
57 new = dev_alloc_skb(max);
68 spin_unlock_irqrestore(&drop_lock, flags);
73 static int uml_net_rx(struct net_device *dev)
75 struct uml_net_private *lp = netdev_priv(dev);
79 /* If we can't allocate memory, try again next round. */
80 skb = dev_alloc_skb(lp->max_packet);
83 /* Read a packet into drop_skb and don't do anything with it. */
84 (*lp->read)(lp->fd, drop_skb, lp);
85 dev->stats.rx_dropped++;
90 skb_put(skb, lp->max_packet);
91 skb_reset_mac_header(skb);
92 pkt_len = (*lp->read)(lp->fd, skb, lp);
95 skb_trim(skb, pkt_len);
96 skb->protocol = (*lp->protocol)(skb);
98 dev->stats.rx_bytes += skb->len;
99 dev->stats.rx_packets++;
108 static void uml_dev_close(struct work_struct *work)
110 struct uml_net_private *lp =
111 container_of(work, struct uml_net_private, work);
115 static irqreturn_t uml_net_interrupt(int irq, void *dev_id)
117 struct net_device *dev = dev_id;
118 struct uml_net_private *lp = netdev_priv(dev);
121 if (!netif_running(dev))
124 spin_lock(&lp->lock);
125 while ((err = uml_net_rx(dev)) > 0) ;
128 "Device '%s' read returned %d, shutting it down\n",
130 /* dev_close can't be called in interrupt context, and takes
132 * And dev_close() can be safely called multiple times on the
133 * same device, since it tests for (dev->flags & IFF_UP). So
134 * there's no harm in delaying the device shutdown.
135 * Furthermore, the workqueue will not re-enqueue an already
136 * enqueued work item. */
137 schedule_work(&lp->work);
141 spin_unlock(&lp->lock);
145 static int uml_net_open(struct net_device *dev)
147 struct uml_net_private *lp = netdev_priv(dev);
155 lp->fd = (*lp->open)(&lp->user);
161 err = um_request_irq(dev->irq, lp->fd, IRQ_READ, uml_net_interrupt,
162 IRQF_SHARED, dev->name, dev);
164 printk(KERN_ERR "uml_net_open: failed to get irq(%d)\n", err);
169 netif_start_queue(dev);
171 /* clear buffer - it can happen that the host side of the interface
172 * is full when we get here. In this case, new data is never queued,
173 * SIGIOs never arrive, and the net never works.
175 while ((err = uml_net_rx(dev)) > 0) ;
177 spin_lock(&opened_lock);
178 list_add(&lp->list, &opened);
179 spin_unlock(&opened_lock);
183 if (lp->close != NULL) (*lp->close)(lp->fd, &lp->user);
189 static int uml_net_close(struct net_device *dev)
191 struct uml_net_private *lp = netdev_priv(dev);
193 netif_stop_queue(dev);
195 um_free_irq(dev->irq, dev);
196 if (lp->close != NULL)
197 (*lp->close)(lp->fd, &lp->user);
200 spin_lock(&opened_lock);
202 spin_unlock(&opened_lock);
207 static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
209 struct uml_net_private *lp = netdev_priv(dev);
213 netif_stop_queue(dev);
215 spin_lock_irqsave(&lp->lock, flags);
217 len = (*lp->write)(lp->fd, skb, lp);
218 skb_tx_timestamp(skb);
220 if (len == skb->len) {
221 dev->stats.tx_packets++;
222 dev->stats.tx_bytes += skb->len;
223 netif_trans_update(dev);
224 netif_start_queue(dev);
226 /* this is normally done in the interrupt when tx finishes */
227 netif_wake_queue(dev);
230 netif_start_queue(dev);
231 dev->stats.tx_dropped++;
234 netif_start_queue(dev);
235 printk(KERN_ERR "uml_net_start_xmit: failed(%d)\n", len);
238 spin_unlock_irqrestore(&lp->lock, flags);
240 dev_consume_skb_any(skb);
245 static void uml_net_set_multicast_list(struct net_device *dev)
250 static void uml_net_tx_timeout(struct net_device *dev)
252 netif_trans_update(dev);
253 netif_wake_queue(dev);
256 #ifdef CONFIG_NET_POLL_CONTROLLER
257 static void uml_net_poll_controller(struct net_device *dev)
259 disable_irq(dev->irq);
260 uml_net_interrupt(dev->irq, dev);
261 enable_irq(dev->irq);
265 static void uml_net_get_drvinfo(struct net_device *dev,
266 struct ethtool_drvinfo *info)
268 strlcpy(info->driver, DRIVER_NAME, sizeof(info->driver));
269 strlcpy(info->version, "42", sizeof(info->version));
272 static const struct ethtool_ops uml_net_ethtool_ops = {
273 .get_drvinfo = uml_net_get_drvinfo,
274 .get_link = ethtool_op_get_link,
275 .get_ts_info = ethtool_op_get_ts_info,
278 static void uml_net_user_timer_expire(struct timer_list *t)
281 struct uml_net_private *lp = from_timer(lp, t, tl);
282 struct connection *conn = &lp->user;
284 dprintk(KERN_INFO "uml_net_user_timer_expire [%p]\n", conn);
289 void uml_net_setup_etheraddr(struct net_device *dev, char *str)
291 unsigned char *addr = dev->dev_addr;
298 for (i = 0; i < 6; i++) {
299 addr[i] = simple_strtoul(str, &end, 16);
301 ((*end != ':') && (*end != ',') && (*end != '\0'))) {
303 "setup_etheraddr: failed to parse '%s' "
304 "as an ethernet address\n", str);
309 if (is_multicast_ether_addr(addr)) {
311 "Attempt to assign a multicast ethernet address to a "
312 "device disallowed\n");
315 if (!is_valid_ether_addr(addr)) {
317 "Attempt to assign an invalid ethernet address to a "
318 "device disallowed\n");
321 if (!is_local_ether_addr(addr)) {
323 "Warning: Assigning a globally valid ethernet "
324 "address to a device\n");
325 printk(KERN_WARNING "You should set the 2nd rightmost bit in "
326 "the first byte of the MAC,\n");
327 printk(KERN_WARNING "i.e. %02x:%02x:%02x:%02x:%02x:%02x\n",
328 addr[0] | 0x02, addr[1], addr[2], addr[3], addr[4],
335 "Choosing a random ethernet address for device %s\n", dev->name);
336 eth_hw_addr_random(dev);
339 static DEFINE_SPINLOCK(devices_lock);
340 static LIST_HEAD(devices);
342 static struct platform_driver uml_net_driver = {
348 static void net_device_release(struct device *dev)
350 struct uml_net *device = dev_get_drvdata(dev);
351 struct net_device *netdev = device->dev;
352 struct uml_net_private *lp = netdev_priv(netdev);
354 if (lp->remove != NULL)
355 (*lp->remove)(&lp->user);
356 list_del(&device->list);
361 static const struct net_device_ops uml_netdev_ops = {
362 .ndo_open = uml_net_open,
363 .ndo_stop = uml_net_close,
364 .ndo_start_xmit = uml_net_start_xmit,
365 .ndo_set_rx_mode = uml_net_set_multicast_list,
366 .ndo_tx_timeout = uml_net_tx_timeout,
367 .ndo_set_mac_address = eth_mac_addr,
368 .ndo_validate_addr = eth_validate_addr,
369 #ifdef CONFIG_NET_POLL_CONTROLLER
370 .ndo_poll_controller = uml_net_poll_controller,
375 * Ensures that platform_driver_register is called only once by
376 * eth_configure. Will be set in an initcall.
378 static int driver_registered;
380 static void eth_configure(int n, void *init, char *mac,
381 struct transport *transport, gfp_t gfp_mask)
383 struct uml_net *device;
384 struct net_device *dev;
385 struct uml_net_private *lp;
388 size = transport->private_size + sizeof(struct uml_net_private);
390 device = kzalloc(sizeof(*device), gfp_mask);
391 if (device == NULL) {
392 printk(KERN_ERR "eth_configure failed to allocate struct "
397 dev = alloc_etherdev(size);
399 printk(KERN_ERR "eth_configure: failed to allocate struct "
400 "net_device for eth%d\n", n);
401 goto out_free_device;
404 INIT_LIST_HEAD(&device->list);
407 /* If this name ends up conflicting with an existing registered
408 * netdevice, that is OK, register_netdev{,ice}() will notice this
411 snprintf(dev->name, sizeof(dev->name), "eth%d", n);
413 uml_net_setup_etheraddr(dev, mac);
415 printk(KERN_INFO "Netdevice %d (%pM) : ", n, dev->dev_addr);
417 lp = netdev_priv(dev);
418 /* This points to the transport private data. It's still clear, but we
419 * must memset it to 0 *now*. Let's help the drivers. */
421 INIT_WORK(&lp->work, uml_dev_close);
424 if (!driver_registered) {
425 platform_driver_register(¨_net_driver);
426 driver_registered = 1;
429 device->pdev.name = DRIVER_NAME;
430 device->pdev.dev.release = net_device_release;
431 dev_set_drvdata(&device->pdev.dev, device);
432 if (platform_device_register(&device->pdev))
433 goto out_free_netdev;
434 SET_NETDEV_DEV(dev,&device->pdev.dev);
439 * These just fill in a data structure, so there's no failure
440 * to be worried about.
442 (*transport->kern->init)(dev, init);
444 *lp = ((struct uml_net_private)
445 { .list = LIST_HEAD_INIT(lp->list),
448 .mac = { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0},
449 .max_packet = transport->user->max_packet,
450 .protocol = transport->kern->protocol,
451 .open = transport->user->open,
452 .close = transport->user->close,
453 .remove = transport->user->remove,
454 .read = transport->kern->read,
455 .write = transport->kern->write,
456 .add_address = transport->user->add_address,
457 .delete_address = transport->user->delete_address });
459 timer_setup(&lp->tl, uml_net_user_timer_expire, 0);
460 spin_lock_init(&lp->lock);
461 memcpy(lp->mac, dev->dev_addr, sizeof(lp->mac));
463 if ((transport->user->init != NULL) &&
464 ((*transport->user->init)(&lp->user, dev) != 0))
467 dev->mtu = transport->user->mtu;
468 dev->netdev_ops = ¨_netdev_ops;
469 dev->ethtool_ops = ¨_net_ethtool_ops;
470 dev->watchdog_timeo = (HZ >> 1);
471 dev->irq = UM_ETH_IRQ;
473 err = update_drop_skb(lp->max_packet);
475 goto out_undo_user_init;
478 err = register_netdevice(dev);
481 goto out_undo_user_init;
483 spin_lock(&devices_lock);
484 list_add(&device->list, &devices);
485 spin_unlock(&devices_lock);
490 if (transport->user->remove != NULL)
491 (*transport->user->remove)(&lp->user);
493 platform_device_unregister(&device->pdev);
494 return; /* platform_device_unregister frees dev and device */
501 static struct uml_net *find_device(int n)
503 struct uml_net *device;
504 struct list_head *ele;
506 spin_lock(&devices_lock);
507 list_for_each(ele, &devices) {
508 device = list_entry(ele, struct uml_net, list);
509 if (device->index == n)
514 spin_unlock(&devices_lock);
518 static int eth_parse(char *str, int *index_out, char **str_out,
522 int n, err = -EINVAL;
524 n = simple_strtoul(str, &end, 0);
526 *error_out = "Bad device number";
532 *error_out = "Expected '=' after device number";
537 if (find_device(n)) {
538 *error_out = "Device already configured";
548 struct list_head list;
553 static DEFINE_SPINLOCK(transports_lock);
554 static LIST_HEAD(transports);
556 /* Filled in during early boot */
557 static LIST_HEAD(eth_cmd_line);
559 static int check_transport(struct transport *transport, char *eth, int n,
560 void **init_out, char **mac_out, gfp_t gfp_mask)
564 len = strlen(transport->name);
565 if (strncmp(eth, transport->name, len))
571 else if (*eth != '\0')
574 *init_out = kmalloc(transport->setup_size, gfp_mask);
575 if (*init_out == NULL)
578 if (!transport->setup(eth, mac_out, *init_out)) {
585 void register_transport(struct transport *new)
587 struct list_head *ele, *next;
588 struct eth_init *eth;
593 spin_lock(&transports_lock);
594 BUG_ON(!list_empty(&new->list));
595 list_add(&new->list, &transports);
596 spin_unlock(&transports_lock);
598 list_for_each_safe(ele, next, ð_cmd_line) {
599 eth = list_entry(ele, struct eth_init, list);
600 match = check_transport(new, eth->init, eth->index, &init,
604 else if (init != NULL) {
605 eth_configure(eth->index, init, mac, new, GFP_KERNEL);
608 list_del(ð->list);
612 static int eth_setup_common(char *str, int index)
614 struct list_head *ele;
615 struct transport *transport;
620 spin_lock(&transports_lock);
621 list_for_each(ele, &transports) {
622 transport = list_entry(ele, struct transport, list);
623 if (!check_transport(transport, str, index, &init,
627 eth_configure(index, init, mac, transport, GFP_ATOMIC);
634 spin_unlock(&transports_lock);
638 static int __init eth_setup(char *str)
640 struct eth_init *new;
644 err = eth_parse(str, &n, &str, &error);
646 printk(KERN_ERR "eth_setup - Couldn't parse '%s' : %s\n",
651 new = memblock_alloc(sizeof(*new), SMP_CACHE_BYTES);
653 panic("%s: Failed to allocate %zu bytes\n", __func__,
656 INIT_LIST_HEAD(&new->list);
660 list_add_tail(&new->list, ð_cmd_line);
664 __setup("eth", eth_setup);
665 __uml_help(eth_setup,
666 "eth[0-9]+=<transport>,<options>\n"
667 " Configure a network device.\n\n"
670 static int net_config(char *str, char **error_out)
674 err = eth_parse(str, &n, &str, error_out);
678 /* This string is broken up and the pieces used by the underlying
679 * driver. So, it is freed only if eth_setup_common fails.
681 str = kstrdup(str, GFP_KERNEL);
683 *error_out = "net_config failed to strdup string";
686 err = !eth_setup_common(str, n);
692 static int net_id(char **str, int *start_out, int *end_out)
697 n = simple_strtoul(*str, &end, 0);
698 if ((*end != '\0') || (end == *str))
707 static int net_remove(int n, char **error_out)
709 struct uml_net *device;
710 struct net_device *dev;
711 struct uml_net_private *lp;
713 device = find_device(n);
718 lp = netdev_priv(dev);
721 unregister_netdev(dev);
722 platform_device_unregister(&device->pdev);
727 static struct mc_device net_mc = {
728 .list = LIST_HEAD_INIT(net_mc.list),
730 .config = net_config,
733 .remove = net_remove,
737 static int uml_inetaddr_event(struct notifier_block *this, unsigned long event,
740 struct in_ifaddr *ifa = ptr;
741 struct net_device *dev = ifa->ifa_dev->dev;
742 struct uml_net_private *lp;
743 void (*proc)(unsigned char *, unsigned char *, void *);
744 unsigned char addr_buf[4], netmask_buf[4];
746 if (dev->netdev_ops->ndo_open != uml_net_open)
749 lp = netdev_priv(dev);
754 proc = lp->add_address;
757 proc = lp->delete_address;
761 memcpy(addr_buf, &ifa->ifa_address, sizeof(addr_buf));
762 memcpy(netmask_buf, &ifa->ifa_mask, sizeof(netmask_buf));
763 (*proc)(addr_buf, netmask_buf, &lp->user);
768 /* uml_net_init shouldn't be called twice on two CPUs at the same time */
769 static struct notifier_block uml_inetaddr_notifier = {
770 .notifier_call = uml_inetaddr_event,
773 static void inet_register(void)
775 struct list_head *ele;
776 struct uml_net_private *lp;
777 struct in_device *ip;
778 struct in_ifaddr *in;
780 register_inetaddr_notifier(¨_inetaddr_notifier);
782 /* Devices may have been opened already, so the uml_inetaddr_notifier
783 * didn't get a chance to run for them. This fakes it so that
784 * addresses which have already been set up get handled properly.
786 spin_lock(&opened_lock);
787 list_for_each(ele, &opened) {
788 lp = list_entry(ele, struct uml_net_private, list);
789 ip = lp->dev->ip_ptr;
794 uml_inetaddr_event(NULL, NETDEV_UP, in);
798 spin_unlock(&opened_lock);
801 static inline void inet_register(void)
806 static int uml_net_init(void)
808 mconsole_register_dev(&net_mc);
813 __initcall(uml_net_init);
815 static void close_devices(void)
817 struct list_head *ele;
818 struct uml_net_private *lp;
820 spin_lock(&opened_lock);
821 list_for_each(ele, &opened) {
822 lp = list_entry(ele, struct uml_net_private, list);
823 um_free_irq(lp->dev->irq, lp->dev);
824 if ((lp->close != NULL) && (lp->fd >= 0))
825 (*lp->close)(lp->fd, &lp->user);
826 if (lp->remove != NULL)
827 (*lp->remove)(&lp->user);
829 spin_unlock(&opened_lock);
832 __uml_exitcall(close_devices);
834 void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *,
838 struct net_device *dev = d;
839 struct in_device *ip = dev->ip_ptr;
840 struct in_ifaddr *in;
841 unsigned char address[4], netmask[4];
843 if (ip == NULL) return;
846 memcpy(address, &in->ifa_address, sizeof(address));
847 memcpy(netmask, &in->ifa_mask, sizeof(netmask));
848 (*cb)(address, netmask, arg);
853 int dev_netmask(void *d, void *m)
855 struct net_device *dev = d;
856 struct in_device *ip = dev->ip_ptr;
857 struct in_ifaddr *in;
858 __be32 *mask_out = m;
867 *mask_out = in->ifa_mask;
871 void *get_output_buffer(int *len_out)
875 ret = (void *) __get_free_pages(GFP_KERNEL, 0);
876 if (ret) *len_out = PAGE_SIZE;
881 void free_output_buffer(void *buffer)
883 free_pages((unsigned long) buffer, 0);
886 int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out,
891 remain = split_if_spec(str, dev_name, mac_out, gate_addr, NULL);
892 if (remain != NULL) {
893 printk(KERN_ERR "tap_setup_common - Extra garbage on "
894 "specification : '%s'\n", remain);
901 unsigned short eth_protocol(struct sk_buff *skb)
903 return eth_type_trans(skb, skb->dev);