net/bridge/br_device.c

   1 /*
   2  *      Device handling code
   3  *      Linux ethernet bridge
   4  *
   5  *      Authors:
   6  *      Lennert Buytenhek               <buytenh@gnu.org>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/netpoll.h>
  17 #include <linux/etherdevice.h>
  18 #include <linux/ethtool.h>
  19 #include <linux/list.h>
  20 #include <linux/netfilter_bridge.h>
  21
  22 #include <asm/uaccess.h>
  23 #include "br_private.h"
  24
  25 /* net device transmit always called with no BH (preempt_disabled) */
  26 netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
  27 {
  28         struct net_bridge *br = netdev_priv(dev);
  29         const unsigned char *dest = skb->data;
  30         struct net_bridge_fdb_entry *dst;
  31         struct net_bridge_mdb_entry *mdst;
  32         struct br_cpu_netstats *brstats = this_cpu_ptr(br->stats);
  33
  34 #ifdef CONFIG_BRIDGE_NETFILTER
  35         if (skb->nf_bridge && (skb->nf_bridge->mask & BRNF_BRIDGED_DNAT)) {
  36                 br_nf_pre_routing_finish_bridge_slow(skb);
  37                 return NETDEV_TX_OK;
  38         }
  39 #endif
  40
  41         brstats->tx_packets++;
  42         brstats->tx_bytes += skb->len;
  43
  44         BR_INPUT_SKB_CB(skb)->brdev = dev;
  45
  46         skb_reset_mac_header(skb);
  47         skb_pull(skb, ETH_HLEN);
  48
  49         if (is_multicast_ether_addr(dest)) {
  50                 if (br_multicast_rcv(br, NULL, skb))
  51                         goto out;
  52
  53                 mdst = br_mdb_get(br, skb);
  54                 if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb))
  55                         br_multicast_deliver(mdst, skb);
  56                 else
  57                         br_flood_deliver(br, skb);
  58         } else if ((dst = __br_fdb_get(br, dest)) != NULL)
  59                 br_deliver(dst->dst, skb);
  60         else
  61                 br_flood_deliver(br, skb);
  62
  63 out:
  64         return NETDEV_TX_OK;
  65 }
  66
  67 static int br_dev_open(struct net_device *dev)
  68 {
  69         struct net_bridge *br = netdev_priv(dev);
  70
  71         br_features_recompute(br);
  72         netif_start_queue(dev);
  73         br_stp_enable_bridge(br);
  74         br_multicast_open(br);
  75
  76         return 0;
  77 }
  78
  79 static void br_dev_set_multicast_list(struct net_device *dev)
  80 {
  81 }
  82
  83 static int br_dev_stop(struct net_device *dev)
  84 {
  85         struct net_bridge *br = netdev_priv(dev);
  86
  87         br_stp_disable_bridge(br);
  88         br_multicast_stop(br);
  89
  90         netif_stop_queue(dev);
  91
  92         return 0;
  93 }
  94
  95 static struct net_device_stats *br_get_stats(struct net_device *dev)
  96 {
  97         struct net_bridge *br = netdev_priv(dev);
  98         struct net_device_stats *stats = &dev->stats;
  99         struct br_cpu_netstats sum = { 0 };
 100         unsigned int cpu;
 101
 102         for_each_possible_cpu(cpu) {
 103                 const struct br_cpu_netstats *bstats
 104                         = per_cpu_ptr(br->stats, cpu);
 105
 106                 sum.tx_bytes   += bstats->tx_bytes;
 107                 sum.tx_packets += bstats->tx_packets;
 108                 sum.rx_bytes   += bstats->rx_bytes;
 109                 sum.rx_packets += bstats->rx_packets;
 110         }
 111
 112         stats->tx_bytes   = sum.tx_bytes;
 113         stats->tx_packets = sum.tx_packets;
 114         stats->rx_bytes   = sum.rx_bytes;
 115         stats->rx_packets = sum.rx_packets;
 116
 117         return stats;
 118 }
 119
 120 static int br_change_mtu(struct net_device *dev, int new_mtu)
 121 {
 122         struct net_bridge *br = netdev_priv(dev);
 123         if (new_mtu < 68 || new_mtu > br_min_mtu(br))
 124                 return -EINVAL;
 125
 126         dev->mtu = new_mtu;
 127
 128 #ifdef CONFIG_BRIDGE_NETFILTER
 129         /* remember the MTU in the rtable for PMTU */
 130         br->fake_rtable.u.dst.metrics[RTAX_MTU - 1] = new_mtu;
 131 #endif
 132
 133         return 0;
 134 }
 135
 136 /* Allow setting mac address to any valid ethernet address. */
 137 static int br_set_mac_address(struct net_device *dev, void *p)
 138 {
 139         struct net_bridge *br = netdev_priv(dev);
 140         struct sockaddr *addr = p;
 141
 142         if (!is_valid_ether_addr(addr->sa_data))
 143                 return -EINVAL;
 144
 145         spin_lock_bh(&br->lock);
 146         memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 147         br_stp_change_bridge_id(br, addr->sa_data);
 148         br->flags |= BR_SET_MAC_ADDR;
 149         spin_unlock_bh(&br->lock);
 150
 151         return 0;
 152 }
 153
 154 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info)
 155 {
 156         strcpy(info->driver, "bridge");
 157         strcpy(info->version, BR_VERSION);
 158         strcpy(info->fw_version, "N/A");
 159         strcpy(info->bus_info, "N/A");
 160 }
 161
 162 static int br_set_sg(struct net_device *dev, u32 data)
 163 {
 164         struct net_bridge *br = netdev_priv(dev);
 165
 166         if (data)
 167                 br->feature_mask |= NETIF_F_SG;
 168         else
 169                 br->feature_mask &= ~NETIF_F_SG;
 170
 171         br_features_recompute(br);
 172         return 0;
 173 }
 174
 175 static int br_set_tso(struct net_device *dev, u32 data)
 176 {
 177         struct net_bridge *br = netdev_priv(dev);
 178
 179         if (data)
 180                 br->feature_mask |= NETIF_F_TSO;
 181         else
 182                 br->feature_mask &= ~NETIF_F_TSO;
 183
 184         br_features_recompute(br);
 185         return 0;
 186 }
 187
 188 static int br_set_tx_csum(struct net_device *dev, u32 data)
 189 {
 190         struct net_bridge *br = netdev_priv(dev);
 191
 192         if (data)
 193                 br->feature_mask |= NETIF_F_NO_CSUM;
 194         else
 195                 br->feature_mask &= ~NETIF_F_ALL_CSUM;
 196
 197         br_features_recompute(br);
 198         return 0;
 199 }
 200
 201 #ifdef CONFIG_NET_POLL_CONTROLLER
 202 static bool br_devices_support_netpoll(struct net_bridge *br)
 203 {
 204         struct net_bridge_port *p;
 205         bool ret = true;
 206         int count = 0;
 207         unsigned long flags;
 208
 209         spin_lock_irqsave(&br->lock, flags);
 210         list_for_each_entry(p, &br->port_list, list) {
 211                 count++;
 212                 if ((p->dev->priv_flags & IFF_DISABLE_NETPOLL) ||
 213                     !p->dev->netdev_ops->ndo_poll_controller)
 214                         ret = false;
 215         }
 216         spin_unlock_irqrestore(&br->lock, flags);
 217         return count != 0 && ret;
 218 }
 219
 220 static void br_poll_controller(struct net_device *br_dev)
 221 {
 222         struct netpoll *np = br_dev->npinfo->netpoll;
 223
 224         if (np->real_dev != br_dev)
 225                 netpoll_poll_dev(np->real_dev);
 226 }
 227
 228 void br_netpoll_cleanup(struct net_device *dev)
 229 {
 230         struct net_bridge *br = netdev_priv(dev);
 231         struct net_bridge_port *p, *n;
 232         const struct net_device_ops *ops;
 233
 234         br->dev->npinfo = NULL;
 235         list_for_each_entry_safe(p, n, &br->port_list, list) {
 236                 if (p->dev) {
 237                         ops = p->dev->netdev_ops;
 238                         if (ops->ndo_netpoll_cleanup)
 239                                 ops->ndo_netpoll_cleanup(p->dev);
 240                         else
 241                                 p->dev->npinfo = NULL;
 242                 }
 243         }
 244 }
 245
 246 void br_netpoll_disable(struct net_bridge *br,
 247                         struct net_device *dev)
 248 {
 249         if (br_devices_support_netpoll(br))
 250                 br->dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
 251         if (dev->netdev_ops->ndo_netpoll_cleanup)
 252                 dev->netdev_ops->ndo_netpoll_cleanup(dev);
 253         else
 254                 dev->npinfo = NULL;
 255 }
 256
 257 void br_netpoll_enable(struct net_bridge *br,
 258                        struct net_device *dev)
 259 {
 260         if (br_devices_support_netpoll(br)) {
 261                 br->dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
 262                 if (br->dev->npinfo)
 263                         dev->npinfo = br->dev->npinfo;
 264         } else if (!(br->dev->priv_flags & IFF_DISABLE_NETPOLL)) {
 265                 br->dev->priv_flags |= IFF_DISABLE_NETPOLL;
 266                 br_info(br,"new device %s does not support netpoll (disabling)",
 267                         dev->name);
 268         }
 269 }
 270
 271 #endif
 272
 273 static const struct ethtool_ops br_ethtool_ops = {
 274         .get_drvinfo    = br_getinfo,
 275         .get_link       = ethtool_op_get_link,
 276         .get_tx_csum    = ethtool_op_get_tx_csum,
 277         .set_tx_csum    = br_set_tx_csum,
 278         .get_sg         = ethtool_op_get_sg,
 279         .set_sg         = br_set_sg,
 280         .get_tso        = ethtool_op_get_tso,
 281         .set_tso        = br_set_tso,
 282         .get_ufo        = ethtool_op_get_ufo,
 283         .set_ufo        = ethtool_op_set_ufo,
 284         .get_flags      = ethtool_op_get_flags,
 285 };
 286
 287 static const struct net_device_ops br_netdev_ops = {
 288         .ndo_open                = br_dev_open,
 289         .ndo_stop                = br_dev_stop,
 290         .ndo_start_xmit          = br_dev_xmit,
 291         .ndo_get_stats           = br_get_stats,
 292         .ndo_set_mac_address     = br_set_mac_address,
 293         .ndo_set_multicast_list  = br_dev_set_multicast_list,
 294         .ndo_change_mtu          = br_change_mtu,
 295         .ndo_do_ioctl            = br_dev_ioctl,
 296 #ifdef CONFIG_NET_POLL_CONTROLLER
 297         .ndo_netpoll_cleanup     = br_netpoll_cleanup,
 298         .ndo_poll_controller     = br_poll_controller,
 299 #endif
 300 };
 301
 302 static void br_dev_free(struct net_device *dev)
 303 {
 304         struct net_bridge *br = netdev_priv(dev);
 305
 306         free_percpu(br->stats);
 307         free_netdev(dev);
 308 }
 309
 310 void br_dev_setup(struct net_device *dev)
 311 {
 312         random_ether_addr(dev->dev_addr);
 313         ether_setup(dev);
 314
 315         dev->netdev_ops = &br_netdev_ops;
 316         dev->destructor = br_dev_free;
 317         SET_ETHTOOL_OPS(dev, &br_ethtool_ops);
 318         dev->tx_queue_len = 0;
 319         dev->priv_flags = IFF_EBRIDGE;
 320
 321         dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
 322                         NETIF_F_GSO_MASK | NETIF_F_NO_CSUM | NETIF_F_LLTX |
 323                         NETIF_F_NETNS_LOCAL | NETIF_F_GSO;
 324 }