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 BH 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         rcu_read_lock();
  50         if (is_multicast_ether_addr(dest)) {
  51                 if (br_multicast_rcv(br, NULL, skb))
  52                         goto out;
  53
  54                 mdst = br_mdb_get(br, skb);
  55                 if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb))
  56                         br_multicast_deliver(mdst, skb);
  57                 else
  58                         br_flood_deliver(br, skb);
  59         } else if ((dst = __br_fdb_get(br, dest)) != NULL)
  60                 br_deliver(dst->dst, skb);
  61         else
  62                 br_flood_deliver(br, skb);
  63
  64 out:
  65         rcu_read_unlock();
  66         return NETDEV_TX_OK;
  67 }
  68
  69 static int br_dev_open(struct net_device *dev)
  70 {
  71         struct net_bridge *br = netdev_priv(dev);
  72
  73         br_features_recompute(br);
  74         netif_start_queue(dev);
  75         br_stp_enable_bridge(br);
  76         br_multicast_open(br);
  77
  78         return 0;
  79 }
  80
  81 static void br_dev_set_multicast_list(struct net_device *dev)
  82 {
  83 }
  84
  85 static int br_dev_stop(struct net_device *dev)
  86 {
  87         struct net_bridge *br = netdev_priv(dev);
  88
  89         br_stp_disable_bridge(br);
  90         br_multicast_stop(br);
  91
  92         netif_stop_queue(dev);
  93
  94         return 0;
  95 }
  96
  97 static struct net_device_stats *br_get_stats(struct net_device *dev)
  98 {
  99         struct net_bridge *br = netdev_priv(dev);
 100         struct net_device_stats *stats = &dev->stats;
 101         struct br_cpu_netstats sum = { 0 };
 102         unsigned int cpu;
 103
 104         for_each_possible_cpu(cpu) {
 105                 const struct br_cpu_netstats *bstats
 106                         = per_cpu_ptr(br->stats, cpu);
 107
 108                 sum.tx_bytes   += bstats->tx_bytes;
 109                 sum.tx_packets += bstats->tx_packets;
 110                 sum.rx_bytes   += bstats->rx_bytes;
 111                 sum.rx_packets += bstats->rx_packets;
 112         }
 113
 114         stats->tx_bytes   = sum.tx_bytes;
 115         stats->tx_packets = sum.tx_packets;
 116         stats->rx_bytes   = sum.rx_bytes;
 117         stats->rx_packets = sum.rx_packets;
 118
 119         return stats;
 120 }
 121
 122 static int br_change_mtu(struct net_device *dev, int new_mtu)
 123 {
 124         struct net_bridge *br = netdev_priv(dev);
 125         if (new_mtu < 68 || new_mtu > br_min_mtu(br))
 126                 return -EINVAL;
 127
 128         dev->mtu = new_mtu;
 129
 130 #ifdef CONFIG_BRIDGE_NETFILTER
 131         /* remember the MTU in the rtable for PMTU */
 132         br->fake_rtable.u.dst.metrics[RTAX_MTU - 1] = new_mtu;
 133 #endif
 134
 135         return 0;
 136 }
 137
 138 /* Allow setting mac address to any valid ethernet address. */
 139 static int br_set_mac_address(struct net_device *dev, void *p)
 140 {
 141         struct net_bridge *br = netdev_priv(dev);
 142         struct sockaddr *addr = p;
 143
 144         if (!is_valid_ether_addr(addr->sa_data))
 145                 return -EINVAL;
 146
 147         spin_lock_bh(&br->lock);
 148         memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 149         br_stp_change_bridge_id(br, addr->sa_data);
 150         br->flags |= BR_SET_MAC_ADDR;
 151         spin_unlock_bh(&br->lock);
 152
 153         return 0;
 154 }
 155
 156 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info)
 157 {
 158         strcpy(info->driver, "bridge");
 159         strcpy(info->version, BR_VERSION);
 160         strcpy(info->fw_version, "N/A");
 161         strcpy(info->bus_info, "N/A");
 162 }
 163
 164 static int br_set_sg(struct net_device *dev, u32 data)
 165 {
 166         struct net_bridge *br = netdev_priv(dev);
 167
 168         if (data)
 169                 br->feature_mask |= NETIF_F_SG;
 170         else
 171                 br->feature_mask &= ~NETIF_F_SG;
 172
 173         br_features_recompute(br);
 174         return 0;
 175 }
 176
 177 static int br_set_tso(struct net_device *dev, u32 data)
 178 {
 179         struct net_bridge *br = netdev_priv(dev);
 180
 181         if (data)
 182                 br->feature_mask |= NETIF_F_TSO;
 183         else
 184                 br->feature_mask &= ~NETIF_F_TSO;
 185
 186         br_features_recompute(br);
 187         return 0;
 188 }
 189
 190 static int br_set_tx_csum(struct net_device *dev, u32 data)
 191 {
 192         struct net_bridge *br = netdev_priv(dev);
 193
 194         if (data)
 195                 br->feature_mask |= NETIF_F_NO_CSUM;
 196         else
 197                 br->feature_mask &= ~NETIF_F_ALL_CSUM;
 198
 199         br_features_recompute(br);
 200         return 0;
 201 }
 202
 203 #ifdef CONFIG_NET_POLL_CONTROLLER
 204 static bool br_devices_support_netpoll(struct net_bridge *br)
 205 {
 206         struct net_bridge_port *p;
 207         bool ret = true;
 208         int count = 0;
 209         unsigned long flags;
 210
 211         spin_lock_irqsave(&br->lock, flags);
 212         list_for_each_entry(p, &br->port_list, list) {
 213                 count++;
 214                 if ((p->dev->priv_flags & IFF_DISABLE_NETPOLL) ||
 215                     !p->dev->netdev_ops->ndo_poll_controller)
 216                         ret = false;
 217         }
 218         spin_unlock_irqrestore(&br->lock, flags);
 219         return count != 0 && ret;
 220 }
 221
 222 void br_netpoll_cleanup(struct net_device *dev)
 223 {
 224         struct net_bridge *br = netdev_priv(dev);
 225         struct net_bridge_port *p, *n;
 226         const struct net_device_ops *ops;
 227
 228         br->dev->npinfo = NULL;
 229         list_for_each_entry_safe(p, n, &br->port_list, list) {
 230                 if (p->dev) {
 231                         ops = p->dev->netdev_ops;
 232                         if (ops->ndo_netpoll_cleanup)
 233                                 ops->ndo_netpoll_cleanup(p->dev);
 234                         else
 235                                 p->dev->npinfo = NULL;
 236                 }
 237         }
 238 }
 239
 240 void br_netpoll_disable(struct net_bridge *br,
 241                         struct net_device *dev)
 242 {
 243         if (br_devices_support_netpoll(br))
 244                 br->dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
 245         if (dev->netdev_ops->ndo_netpoll_cleanup)
 246                 dev->netdev_ops->ndo_netpoll_cleanup(dev);
 247         else
 248                 dev->npinfo = NULL;
 249 }
 250
 251 void br_netpoll_enable(struct net_bridge *br,
 252                        struct net_device *dev)
 253 {
 254         if (br_devices_support_netpoll(br)) {
 255                 br->dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
 256                 if (br->dev->npinfo)
 257                         dev->npinfo = br->dev->npinfo;
 258         } else if (!(br->dev->priv_flags & IFF_DISABLE_NETPOLL)) {
 259                 br->dev->priv_flags |= IFF_DISABLE_NETPOLL;
 260                 br_info(br,"new device %s does not support netpoll (disabling)",
 261                         dev->name);
 262         }
 263 }
 264
 265 #endif
 266
 267 static const struct ethtool_ops br_ethtool_ops = {
 268         .get_drvinfo    = br_getinfo,
 269         .get_link       = ethtool_op_get_link,
 270         .get_tx_csum    = ethtool_op_get_tx_csum,
 271         .set_tx_csum    = br_set_tx_csum,
 272         .get_sg         = ethtool_op_get_sg,
 273         .set_sg         = br_set_sg,
 274         .get_tso        = ethtool_op_get_tso,
 275         .set_tso        = br_set_tso,
 276         .get_ufo        = ethtool_op_get_ufo,
 277         .set_ufo        = ethtool_op_set_ufo,
 278         .get_flags      = ethtool_op_get_flags,
 279 };
 280
 281 static const struct net_device_ops br_netdev_ops = {
 282         .ndo_open                = br_dev_open,
 283         .ndo_stop                = br_dev_stop,
 284         .ndo_start_xmit          = br_dev_xmit,
 285         .ndo_get_stats           = br_get_stats,
 286         .ndo_set_mac_address     = br_set_mac_address,
 287         .ndo_set_multicast_list  = br_dev_set_multicast_list,
 288         .ndo_change_mtu          = br_change_mtu,
 289         .ndo_do_ioctl            = br_dev_ioctl,
 290 #ifdef CONFIG_NET_POLL_CONTROLLER
 291         .ndo_netpoll_cleanup     = br_netpoll_cleanup,
 292 #endif
 293 };
 294
 295 static void br_dev_free(struct net_device *dev)
 296 {
 297         struct net_bridge *br = netdev_priv(dev);
 298
 299         free_percpu(br->stats);
 300         free_netdev(dev);
 301 }
 302
 303 void br_dev_setup(struct net_device *dev)
 304 {
 305         random_ether_addr(dev->dev_addr);
 306         ether_setup(dev);
 307
 308         dev->netdev_ops = &br_netdev_ops;
 309         dev->destructor = br_dev_free;
 310         SET_ETHTOOL_OPS(dev, &br_ethtool_ops);
 311         dev->tx_queue_len = 0;
 312         dev->priv_flags = IFF_EBRIDGE;
 313
 314         dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
 315                         NETIF_F_GSO_MASK | NETIF_F_NO_CSUM | NETIF_F_LLTX |
 316                         NETIF_F_NETNS_LOCAL | NETIF_F_GSO;
 317 }