diff options
Diffstat (limited to 'arch/um/drivers/net_kern.c')
| -rw-r--r-- | arch/um/drivers/net_kern.c | 891 |
1 files changed, 891 insertions, 0 deletions
diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c new file mode 100644 index 000000000..1802cf4ef --- /dev/null +++ b/arch/um/drivers/net_kern.c @@ -0,0 +1,891 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) + * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and + * James Leu (jleu@mindspring.net). + * Copyright (C) 2001 by various other people who didn't put their name here. + */ + +#include <linux/memblock.h> +#include <linux/etherdevice.h> +#include <linux/ethtool.h> +#include <linux/inetdevice.h> +#include <linux/init.h> +#include <linux/list.h> +#include <linux/netdevice.h> +#include <linux/platform_device.h> +#include <linux/rtnetlink.h> +#include <linux/skbuff.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <init.h> +#include <irq_kern.h> +#include <irq_user.h> +#include "mconsole_kern.h" +#include <net_kern.h> +#include <net_user.h> + +#define DRIVER_NAME "uml-netdev" + +static DEFINE_SPINLOCK(opened_lock); +static LIST_HEAD(opened); + +/* + * The drop_skb is used when we can't allocate an skb. The + * packet is read into drop_skb in order to get the data off the + * connection to the host. + * It is reallocated whenever a maximum packet size is seen which is + * larger than any seen before. update_drop_skb is called from + * eth_configure when a new interface is added. + */ +static DEFINE_SPINLOCK(drop_lock); +static struct sk_buff *drop_skb; +static int drop_max; + +static int update_drop_skb(int max) +{ + struct sk_buff *new; + unsigned long flags; + int err = 0; + + spin_lock_irqsave(&drop_lock, flags); + + if (max <= drop_max) + goto out; + + err = -ENOMEM; + new = dev_alloc_skb(max); + if (new == NULL) + goto out; + + skb_put(new, max); + + kfree_skb(drop_skb); + drop_skb = new; + drop_max = max; + err = 0; +out: + spin_unlock_irqrestore(&drop_lock, flags); + + return err; +} + +static int uml_net_rx(struct net_device *dev) +{ + struct uml_net_private *lp = netdev_priv(dev); + int pkt_len; + struct sk_buff *skb; + + /* If we can't allocate memory, try again next round. */ + skb = dev_alloc_skb(lp->max_packet); + if (skb == NULL) { + drop_skb->dev = dev; + /* Read a packet into drop_skb and don't do anything with it. */ + (*lp->read)(lp->fd, drop_skb, lp); + dev->stats.rx_dropped++; + return 0; + } + + skb->dev = dev; + skb_put(skb, lp->max_packet); + skb_reset_mac_header(skb); + pkt_len = (*lp->read)(lp->fd, skb, lp); + + if (pkt_len > 0) { + skb_trim(skb, pkt_len); + skb->protocol = (*lp->protocol)(skb); + + dev->stats.rx_bytes += skb->len; + dev->stats.rx_packets++; + netif_rx(skb); + return pkt_len; + } + + kfree_skb(skb); + return pkt_len; +} + +static void uml_dev_close(struct work_struct *work) +{ + struct uml_net_private *lp = + container_of(work, struct uml_net_private, work); + dev_close(lp->dev); +} + +static irqreturn_t uml_net_interrupt(int irq, void *dev_id) +{ + struct net_device *dev = dev_id; + struct uml_net_private *lp = netdev_priv(dev); + int err; + + if (!netif_running(dev)) + return IRQ_NONE; + + spin_lock(&lp->lock); + while ((err = uml_net_rx(dev)) > 0) ; + if (err < 0) { + printk(KERN_ERR + "Device '%s' read returned %d, shutting it down\n", + dev->name, err); + /* dev_close can't be called in interrupt context, and takes + * again lp->lock. + * And dev_close() can be safely called multiple times on the + * same device, since it tests for (dev->flags & IFF_UP). So + * there's no harm in delaying the device shutdown. + * Furthermore, the workqueue will not re-enqueue an already + * enqueued work item. */ + schedule_work(&lp->work); + goto out; + } +out: + spin_unlock(&lp->lock); + return IRQ_HANDLED; +} + +static int uml_net_open(struct net_device *dev) +{ + struct uml_net_private *lp = netdev_priv(dev); + int err; + + if (lp->fd >= 0) { + err = -ENXIO; + goto out; + } + + lp->fd = (*lp->open)(&lp->user); + if (lp->fd < 0) { + err = lp->fd; + goto out; + } + + err = um_request_irq(dev->irq, lp->fd, IRQ_READ, uml_net_interrupt, + IRQF_SHARED, dev->name, dev); + if (err != 0) { + printk(KERN_ERR "uml_net_open: failed to get irq(%d)\n", err); + err = -ENETUNREACH; + goto out_close; + } + + netif_start_queue(dev); + + /* clear buffer - it can happen that the host side of the interface + * is full when we get here. In this case, new data is never queued, + * SIGIOs never arrive, and the net never works. + */ + while ((err = uml_net_rx(dev)) > 0) ; + + spin_lock(&opened_lock); + list_add(&lp->list, &opened); + spin_unlock(&opened_lock); + + return 0; +out_close: + if (lp->close != NULL) (*lp->close)(lp->fd, &lp->user); + lp->fd = -1; +out: + return err; +} + +static int uml_net_close(struct net_device *dev) +{ + struct uml_net_private *lp = netdev_priv(dev); + + netif_stop_queue(dev); + + um_free_irq(dev->irq, dev); + if (lp->close != NULL) + (*lp->close)(lp->fd, &lp->user); + lp->fd = -1; + + spin_lock(&opened_lock); + list_del(&lp->list); + spin_unlock(&opened_lock); + + return 0; +} + +static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct uml_net_private *lp = netdev_priv(dev); + unsigned long flags; + int len; + + netif_stop_queue(dev); + + spin_lock_irqsave(&lp->lock, flags); + + len = (*lp->write)(lp->fd, skb, lp); + skb_tx_timestamp(skb); + + if (len == skb->len) { + dev->stats.tx_packets++; + dev->stats.tx_bytes += skb->len; + netif_trans_update(dev); + netif_start_queue(dev); + + /* this is normally done in the interrupt when tx finishes */ + netif_wake_queue(dev); + } + else if (len == 0) { + netif_start_queue(dev); + dev->stats.tx_dropped++; + } + else { + netif_start_queue(dev); + printk(KERN_ERR "uml_net_start_xmit: failed(%d)\n", len); + } + + spin_unlock_irqrestore(&lp->lock, flags); + + dev_consume_skb_any(skb); + + return NETDEV_TX_OK; +} + +static void uml_net_set_multicast_list(struct net_device *dev) +{ + return; +} + +static void uml_net_tx_timeout(struct net_device *dev, unsigned int txqueue) +{ + netif_trans_update(dev); + netif_wake_queue(dev); +} + +#ifdef CONFIG_NET_POLL_CONTROLLER +static void uml_net_poll_controller(struct net_device *dev) +{ + disable_irq(dev->irq); + uml_net_interrupt(dev->irq, dev); + enable_irq(dev->irq); +} +#endif + +static void uml_net_get_drvinfo(struct net_device *dev, + struct ethtool_drvinfo *info) +{ + strlcpy(info->driver, DRIVER_NAME, sizeof(info->driver)); +} + +static const struct ethtool_ops uml_net_ethtool_ops = { + .get_drvinfo = uml_net_get_drvinfo, + .get_link = ethtool_op_get_link, + .get_ts_info = ethtool_op_get_ts_info, +}; + +void uml_net_setup_etheraddr(struct net_device *dev, char *str) +{ + unsigned char *addr = dev->dev_addr; + char *end; + int i; + + if (str == NULL) + goto random; + + for (i = 0; i < 6; i++) { + addr[i] = simple_strtoul(str, &end, 16); + if ((end == str) || + ((*end != ':') && (*end != ',') && (*end != '\0'))) { + printk(KERN_ERR + "setup_etheraddr: failed to parse '%s' " + "as an ethernet address\n", str); + goto random; + } + str = end + 1; + } + if (is_multicast_ether_addr(addr)) { + printk(KERN_ERR + "Attempt to assign a multicast ethernet address to a " + "device disallowed\n"); + goto random; + } + if (!is_valid_ether_addr(addr)) { + printk(KERN_ERR + "Attempt to assign an invalid ethernet address to a " + "device disallowed\n"); + goto random; + } + if (!is_local_ether_addr(addr)) { + printk(KERN_WARNING + "Warning: Assigning a globally valid ethernet " + "address to a device\n"); + printk(KERN_WARNING "You should set the 2nd rightmost bit in " + "the first byte of the MAC,\n"); + printk(KERN_WARNING "i.e. %02x:%02x:%02x:%02x:%02x:%02x\n", + addr[0] | 0x02, addr[1], addr[2], addr[3], addr[4], + addr[5]); + } + return; + +random: + printk(KERN_INFO + "Choosing a random ethernet address for device %s\n", dev->name); + eth_hw_addr_random(dev); +} + +static DEFINE_SPINLOCK(devices_lock); +static LIST_HEAD(devices); + +static struct platform_driver uml_net_driver = { + .driver = { + .name = DRIVER_NAME, + }, +}; + +static void net_device_release(struct device *dev) +{ + struct uml_net *device = dev_get_drvdata(dev); + struct net_device *netdev = device->dev; + struct uml_net_private *lp = netdev_priv(netdev); + + if (lp->remove != NULL) + (*lp->remove)(&lp->user); + list_del(&device->list); + kfree(device); + free_netdev(netdev); +} + +static const struct net_device_ops uml_netdev_ops = { + .ndo_open = uml_net_open, + .ndo_stop = uml_net_close, + .ndo_start_xmit = uml_net_start_xmit, + .ndo_set_rx_mode = uml_net_set_multicast_list, + .ndo_tx_timeout = uml_net_tx_timeout, + .ndo_set_mac_address = eth_mac_addr, + .ndo_validate_addr = eth_validate_addr, +#ifdef CONFIG_NET_POLL_CONTROLLER + .ndo_poll_controller = uml_net_poll_controller, +#endif +}; + +/* + * Ensures that platform_driver_register is called only once by + * eth_configure. Will be set in an initcall. + */ +static int driver_registered; + +static void eth_configure(int n, void *init, char *mac, + struct transport *transport, gfp_t gfp_mask) +{ + struct uml_net *device; + struct net_device *dev; + struct uml_net_private *lp; + int err, size; + + size = transport->private_size + sizeof(struct uml_net_private); + + device = kzalloc(sizeof(*device), gfp_mask); + if (device == NULL) { + printk(KERN_ERR "eth_configure failed to allocate struct " + "uml_net\n"); + return; + } + + dev = alloc_etherdev(size); + if (dev == NULL) { + printk(KERN_ERR "eth_configure: failed to allocate struct " + "net_device for eth%d\n", n); + goto out_free_device; + } + + INIT_LIST_HEAD(&device->list); + device->index = n; + + /* If this name ends up conflicting with an existing registered + * netdevice, that is OK, register_netdev{,ice}() will notice this + * and fail. + */ + snprintf(dev->name, sizeof(dev->name), "eth%d", n); + + uml_net_setup_etheraddr(dev, mac); + + printk(KERN_INFO "Netdevice %d (%pM) : ", n, dev->dev_addr); + + lp = netdev_priv(dev); + /* This points to the transport private data. It's still clear, but we + * must memset it to 0 *now*. Let's help the drivers. */ + memset(lp, 0, size); + INIT_WORK(&lp->work, uml_dev_close); + + /* sysfs register */ + if (!driver_registered) { + platform_driver_register(¨_net_driver); + driver_registered = 1; + } + device->pdev.id = n; + device->pdev.name = DRIVER_NAME; + device->pdev.dev.release = net_device_release; + dev_set_drvdata(&device->pdev.dev, device); + if (platform_device_register(&device->pdev)) + goto out_free_netdev; + SET_NETDEV_DEV(dev,&device->pdev.dev); + + device->dev = dev; + + /* + * These just fill in a data structure, so there's no failure + * to be worried about. + */ + (*transport->kern->init)(dev, init); + + *lp = ((struct uml_net_private) + { .list = LIST_HEAD_INIT(lp->list), + .dev = dev, + .fd = -1, + .mac = { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0}, + .max_packet = transport->user->max_packet, + .protocol = transport->kern->protocol, + .open = transport->user->open, + .close = transport->user->close, + .remove = transport->user->remove, + .read = transport->kern->read, + .write = transport->kern->write, + .add_address = transport->user->add_address, + .delete_address = transport->user->delete_address }); + + spin_lock_init(&lp->lock); + memcpy(lp->mac, dev->dev_addr, sizeof(lp->mac)); + + if ((transport->user->init != NULL) && + ((*transport->user->init)(&lp->user, dev) != 0)) + goto out_unregister; + + dev->mtu = transport->user->mtu; + dev->netdev_ops = ¨_netdev_ops; + dev->ethtool_ops = ¨_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, gfp_t gfp_mask) +{ + 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_mask); + 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, ð_cmd_line) { + eth = list_entry(ele, struct eth_init, list); + match = check_transport(new, eth->init, eth->index, &init, + &mac, GFP_KERNEL); + if (!match) + continue; + else if (init != NULL) { + eth_configure(eth->index, init, mac, new, GFP_KERNEL); + kfree(init); + } + list_del(ð->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, GFP_ATOMIC)) + continue; + if (init != NULL) { + eth_configure(index, init, mac, transport, GFP_ATOMIC); + 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 = memblock_alloc(sizeof(*new), SMP_CACHE_BYTES); + if (!new) + panic("%s: Failed to allocate %zu bytes\n", __func__, + sizeof(*new)); + + INIT_LIST_HEAD(&new->list); + new->index = n; + new->init = str; + + list_add_tail(&new->list, ð_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 = netdev_priv(dev); + 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->netdev_ops->ndo_open != uml_net_open) + return NOTIFY_DONE; + + lp = netdev_priv(dev); + + 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 */ +static 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(¨_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); + um_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); +} |