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 (unlikely(netpoll_tx_running(dev))) {
  51                         br_flood_deliver(br, skb);
  52                         goto out;
  53                 }
  54                 if (br_multicast_rcv(br, NULL, skb))
  55                         goto out;
  56
  57                 mdst = br_mdb_get(br, skb);
  58                 if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb))
  59                         br_multicast_deliver(mdst, skb);
  60                 else
  61                         br_flood_deliver(br, skb);
  62         } else if ((dst = __br_fdb_get(br, dest)) != NULL)
  63                 br_deliver(dst->dst, skb);
  64         else
  65                 br_flood_deliver(br, skb);
  66
  67 out:
  68         return NETDEV_TX_OK;
  69 }
  70
  71 static int br_dev_open(struct net_device *dev)
  72 {
  73         struct net_bridge *br = netdev_priv(dev);
  74
  75         br_features_recompute(br);
  76         netif_start_queue(dev);
  77         br_stp_enable_bridge(br);
  78         br_multicast_open(br);
  79
  80         return 0;
  81 }
  82
  83 static void br_dev_set_multicast_list(struct net_device *dev)
  84 {
  85 }
  86
  87 static int br_dev_stop(struct net_device *dev)
  88 {
  89         struct net_bridge *br = netdev_priv(dev);
  90
  91         br_stp_disable_bridge(br);
  92         br_multicast_stop(br);
  93
  94         netif_stop_queue(dev);
  95
  96         return 0;
  97 }
  98
  99 static struct net_device_stats *br_get_stats(struct net_device *dev)
 100 {
 101         struct net_bridge *br = netdev_priv(dev);
 102         struct net_device_stats *stats = &dev->stats;
 103         struct br_cpu_netstats sum = { 0 };
 104         unsigned int cpu;
 105
 106         for_each_possible_cpu(cpu) {
 107                 const struct br_cpu_netstats *bstats
 108                         = per_cpu_ptr(br->stats, cpu);
 109
 110                 sum.tx_bytes   += bstats->tx_bytes;
 111                 sum.tx_packets += bstats->tx_packets;
 112                 sum.rx_bytes   += bstats->rx_bytes;
 113                 sum.rx_packets += bstats->rx_packets;
 114         }
 115
 116         stats->tx_bytes   = sum.tx_bytes;
 117         stats->tx_packets = sum.tx_packets;
 118         stats->rx_bytes   = sum.rx_bytes;
 119         stats->rx_packets = sum.rx_packets;
 120
 121         return stats;
 122 }
 123
 124 static int br_change_mtu(struct net_device *dev, int new_mtu)
 125 {
 126         struct net_bridge *br = netdev_priv(dev);
 127         if (new_mtu < 68 || new_mtu > br_min_mtu(br))
 128                 return -EINVAL;
 129
 130         dev->mtu = new_mtu;
 131
 132 #ifdef CONFIG_BRIDGE_NETFILTER
 133         /* remember the MTU in the rtable for PMTU */
 134         br->fake_rtable.dst.metrics[RTAX_MTU - 1] = new_mtu;
 135 #endif
 136
 137         return 0;
 138 }
 139
 140 /* Allow setting mac address to any valid ethernet address. */
 141 static int br_set_mac_address(struct net_device *dev, void *p)
 142 {
 143         struct net_bridge *br = netdev_priv(dev);
 144         struct sockaddr *addr = p;
 145
 146         if (!is_valid_ether_addr(addr->sa_data))
 147                 return -EINVAL;
 148
 149         spin_lock_bh(&br->lock);
 150         memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 151         br_stp_change_bridge_id(br, addr->sa_data);
 152         br->flags |= BR_SET_MAC_ADDR;
 153         spin_unlock_bh(&br->lock);
 154
 155         return 0;
 156 }
 157
 158 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info)
 159 {
 160         strcpy(info->driver, "bridge");
 161         strcpy(info->version, BR_VERSION);
 162         strcpy(info->fw_version, "N/A");
 163         strcpy(info->bus_info, "N/A");
 164 }
 165
 166 static int br_set_sg(struct net_device *dev, u32 data)
 167 {
 168         struct net_bridge *br = netdev_priv(dev);
 169
 170         if (data)
 171                 br->feature_mask |= NETIF_F_SG;
 172         else
 173                 br->feature_mask &= ~NETIF_F_SG;
 174
 175         br_features_recompute(br);
 176         return 0;
 177 }
 178
 179 static int br_set_tso(struct net_device *dev, u32 data)
 180 {
 181         struct net_bridge *br = netdev_priv(dev);
 182
 183         if (data)
 184                 br->feature_mask |= NETIF_F_TSO;
 185         else
 186                 br->feature_mask &= ~NETIF_F_TSO;
 187
 188         br_features_recompute(br);
 189         return 0;
 190 }
 191
 192 static int br_set_tx_csum(struct net_device *dev, u32 data)
 193 {
 194         struct net_bridge *br = netdev_priv(dev);
 195
 196         if (data)
 197                 br->feature_mask |= NETIF_F_NO_CSUM;
 198         else
 199                 br->feature_mask &= ~NETIF_F_ALL_CSUM;
 200
 201         br_features_recompute(br);
 202         return 0;
 203 }
 204
 205 #ifdef CONFIG_NET_POLL_CONTROLLER
 206 static void br_poll_controller(struct net_device *br_dev)
 207 {
 208 }
 209
 210 static void br_netpoll_cleanup(struct net_device *dev)
 211 {
 212         struct net_bridge *br = netdev_priv(dev);
 213         struct net_bridge_port *p, *n;
 214
 215         list_for_each_entry_safe(p, n, &br->port_list, list) {
 216                 br_netpoll_disable(p);
 217         }
 218 }
 219
 220 static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
 221 {
 222         struct net_bridge *br = netdev_priv(dev);
 223         struct net_bridge_port *p, *n;
 224         int err = 0;
 225
 226         list_for_each_entry_safe(p, n, &br->port_list, list) {
 227                 if (!p->dev)
 228                         continue;
 229
 230                 err = br_netpoll_enable(p);
 231                 if (err)
 232                         goto fail;
 233         }
 234
 235 out:
 236         return err;
 237
 238 fail:
 239         br_netpoll_cleanup(dev);
 240         goto out;
 241 }
 242
 243 int br_netpoll_enable(struct net_bridge_port *p)
 244 {
 245         struct netpoll *np;
 246         int err = 0;
 247
 248         np = kzalloc(sizeof(*p->np), GFP_KERNEL);
 249         err = -ENOMEM;
 250         if (!np)
 251                 goto out;
 252
 253         np->dev = p->dev;
 254
 255         err = __netpoll_setup(np);
 256         if (err) {
 257                 kfree(np);
 258                 goto out;
 259         }
 260
 261         p->np = np;
 262
 263 out:
 264         return err;
 265 }
 266
 267 void br_netpoll_disable(struct net_bridge_port *p)
 268 {
 269         struct netpoll *np = p->np;
 270
 271         if (!np)
 272                 return;
 273
 274         p->np = NULL;
 275
 276         /* Wait for transmitting packets to finish before freeing. */
 277         synchronize_rcu_bh();
 278
 279         __netpoll_cleanup(np);
 280         kfree(np);
 281 }
 282
 283 #endif
 284
 285 static const struct ethtool_ops br_ethtool_ops = {
 286         .get_drvinfo    = br_getinfo,
 287         .get_link       = ethtool_op_get_link,
 288         .get_tx_csum    = ethtool_op_get_tx_csum,
 289         .set_tx_csum    = br_set_tx_csum,
 290         .get_sg         = ethtool_op_get_sg,
 291         .set_sg         = br_set_sg,
 292         .get_tso        = ethtool_op_get_tso,
 293         .set_tso        = br_set_tso,
 294         .get_ufo        = ethtool_op_get_ufo,
 295         .set_ufo        = ethtool_op_set_ufo,
 296         .get_flags      = ethtool_op_get_flags,
 297 };
 298
 299 static const struct net_device_ops br_netdev_ops = {
 300         .ndo_open                = br_dev_open,
 301         .ndo_stop                = br_dev_stop,
 302         .ndo_start_xmit          = br_dev_xmit,
 303         .ndo_get_stats           = br_get_stats,
 304         .ndo_set_mac_address     = br_set_mac_address,
 305         .ndo_set_multicast_list  = br_dev_set_multicast_list,
 306         .ndo_change_mtu          = br_change_mtu,
 307         .ndo_do_ioctl            = br_dev_ioctl,
 308 #ifdef CONFIG_NET_POLL_CONTROLLER
 309         .ndo_netpoll_setup       = br_netpoll_setup,
 310         .ndo_netpoll_cleanup     = br_netpoll_cleanup,
 311         .ndo_poll_controller     = br_poll_controller,
 312 #endif
 313 };
 314
 315 static void br_dev_free(struct net_device *dev)
 316 {
 317         struct net_bridge *br = netdev_priv(dev);
 318
 319         free_percpu(br->stats);
 320         free_netdev(dev);
 321 }
 322
 323 void br_dev_setup(struct net_device *dev)
 324 {
 325         random_ether_addr(dev->dev_addr);
 326         ether_setup(dev);
 327
 328         dev->netdev_ops = &br_netdev_ops;
 329         dev->destructor = br_dev_free;
 330         SET_ETHTOOL_OPS(dev, &br_ethtool_ops);
 331         dev->tx_queue_len = 0;
 332         dev->priv_flags = IFF_EBRIDGE;
 333
 334         dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
 335                         NETIF_F_GSO_MASK | NETIF_F_NO_CSUM | NETIF_F_LLTX |
 336                         NETIF_F_NETNS_LOCAL | NETIF_F_GSO;
 337 }