net/switchdev/switchdev.c

   1 /*
   2  * net/switchdev/switchdev.c - Switch device API
   3  * Copyright (c) 2014 Jiri Pirko <jiri@resnulli.us>
   4  * Copyright (c) 2014-2015 Scott Feldman <sfeldma@gmail.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/types.h>
  14 #include <linux/init.h>
  15 #include <linux/mutex.h>
  16 #include <linux/notifier.h>
  17 #include <linux/netdevice.h>
  18 #include <net/ip_fib.h>
  19 #include <net/switchdev.h>
  20
  21 /**
  22  *      netdev_switch_parent_id_get - Get ID of a switch
  23  *      @dev: port device
  24  *      @psid: switch ID
  25  *
  26  *      Get ID of a switch this port is part of.
  27  */
  28 int netdev_switch_parent_id_get(struct net_device *dev,
  29                                 struct netdev_phys_item_id *psid)
  30 {
  31         const struct net_device_ops *ops = dev->netdev_ops;
  32
  33         if (!ops->ndo_switch_parent_id_get)
  34                 return -EOPNOTSUPP;
  35         return ops->ndo_switch_parent_id_get(dev, psid);
  36 }
  37 EXPORT_SYMBOL_GPL(netdev_switch_parent_id_get);
  38
  39 /**
  40  *      netdev_switch_port_stp_update - Notify switch device port of STP
  41  *                                      state change
  42  *      @dev: port device
  43  *      @state: port STP state
  44  *
  45  *      Notify switch device port of bridge port STP state change.
  46  */
  47 int netdev_switch_port_stp_update(struct net_device *dev, u8 state)
  48 {
  49         const struct net_device_ops *ops = dev->netdev_ops;
  50
  51         if (!ops->ndo_switch_port_stp_update)
  52                 return -EOPNOTSUPP;
  53         WARN_ON(!ops->ndo_switch_parent_id_get);
  54         return ops->ndo_switch_port_stp_update(dev, state);
  55 }
  56 EXPORT_SYMBOL_GPL(netdev_switch_port_stp_update);
  57
  58 static DEFINE_MUTEX(netdev_switch_mutex);
  59 static RAW_NOTIFIER_HEAD(netdev_switch_notif_chain);
  60
  61 /**
  62  *      register_netdev_switch_notifier - Register nofifier
  63  *      @nb: notifier_block
  64  *
  65  *      Register switch device notifier. This should be used by code
  66  *      which needs to monitor events happening in particular device.
  67  *      Return values are same as for atomic_notifier_chain_register().
  68  */
  69 int register_netdev_switch_notifier(struct notifier_block *nb)
  70 {
  71         int err;
  72
  73         mutex_lock(&netdev_switch_mutex);
  74         err = raw_notifier_chain_register(&netdev_switch_notif_chain, nb);
  75         mutex_unlock(&netdev_switch_mutex);
  76         return err;
  77 }
  78 EXPORT_SYMBOL_GPL(register_netdev_switch_notifier);
  79
  80 /**
  81  *      unregister_netdev_switch_notifier - Unregister nofifier
  82  *      @nb: notifier_block
  83  *
  84  *      Unregister switch device notifier.
  85  *      Return values are same as for atomic_notifier_chain_unregister().
  86  */
  87 int unregister_netdev_switch_notifier(struct notifier_block *nb)
  88 {
  89         int err;
  90
  91         mutex_lock(&netdev_switch_mutex);
  92         err = raw_notifier_chain_unregister(&netdev_switch_notif_chain, nb);
  93         mutex_unlock(&netdev_switch_mutex);
  94         return err;
  95 }
  96 EXPORT_SYMBOL_GPL(unregister_netdev_switch_notifier);
  97
  98 /**
  99  *      call_netdev_switch_notifiers - Call nofifiers
 100  *      @val: value passed unmodified to notifier function
 101  *      @dev: port device
 102  *      @info: notifier information data
 103  *
 104  *      Call all network notifier blocks. This should be called by driver
 105  *      when it needs to propagate hardware event.
 106  *      Return values are same as for atomic_notifier_call_chain().
 107  */
 108 int call_netdev_switch_notifiers(unsigned long val, struct net_device *dev,
 109                                  struct netdev_switch_notifier_info *info)
 110 {
 111         int err;
 112
 113         info->dev = dev;
 114         mutex_lock(&netdev_switch_mutex);
 115         err = raw_notifier_call_chain(&netdev_switch_notif_chain, val, info);
 116         mutex_unlock(&netdev_switch_mutex);
 117         return err;
 118 }
 119 EXPORT_SYMBOL_GPL(call_netdev_switch_notifiers);
 120
 121 /**
 122  *      netdev_switch_port_bridge_setlink - Notify switch device port of bridge
 123  *      port attributes
 124  *
 125  *      @dev: port device
 126  *      @nlh: netlink msg with bridge port attributes
 127  *      @flags: bridge setlink flags
 128  *
 129  *      Notify switch device port of bridge port attributes
 130  */
 131 int netdev_switch_port_bridge_setlink(struct net_device *dev,
 132                                       struct nlmsghdr *nlh, u16 flags)
 133 {
 134         const struct net_device_ops *ops = dev->netdev_ops;
 135
 136         if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
 137                 return 0;
 138
 139         if (!ops->ndo_bridge_setlink)
 140                 return -EOPNOTSUPP;
 141
 142         return ops->ndo_bridge_setlink(dev, nlh, flags);
 143 }
 144 EXPORT_SYMBOL_GPL(netdev_switch_port_bridge_setlink);
 145
 146 /**
 147  *      netdev_switch_port_bridge_dellink - Notify switch device port of bridge
 148  *      port attribute delete
 149  *
 150  *      @dev: port device
 151  *      @nlh: netlink msg with bridge port attributes
 152  *      @flags: bridge setlink flags
 153  *
 154  *      Notify switch device port of bridge port attribute delete
 155  */
 156 int netdev_switch_port_bridge_dellink(struct net_device *dev,
 157                                       struct nlmsghdr *nlh, u16 flags)
 158 {
 159         const struct net_device_ops *ops = dev->netdev_ops;
 160
 161         if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
 162                 return 0;
 163
 164         if (!ops->ndo_bridge_dellink)
 165                 return -EOPNOTSUPP;
 166
 167         return ops->ndo_bridge_dellink(dev, nlh, flags);
 168 }
 169 EXPORT_SYMBOL_GPL(netdev_switch_port_bridge_dellink);
 170
 171 /**
 172  *      ndo_dflt_netdev_switch_port_bridge_setlink - default ndo bridge setlink
 173  *                                                   op for master devices
 174  *
 175  *      @dev: port device
 176  *      @nlh: netlink msg with bridge port attributes
 177  *      @flags: bridge setlink flags
 178  *
 179  *      Notify master device slaves of bridge port attributes
 180  */
 181 int ndo_dflt_netdev_switch_port_bridge_setlink(struct net_device *dev,
 182                                                struct nlmsghdr *nlh, u16 flags)
 183 {
 184         struct net_device *lower_dev;
 185         struct list_head *iter;
 186         int ret = 0, err = 0;
 187
 188         if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
 189                 return ret;
 190
 191         netdev_for_each_lower_dev(dev, lower_dev, iter) {
 192                 err = netdev_switch_port_bridge_setlink(lower_dev, nlh, flags);
 193                 if (err && err != -EOPNOTSUPP)
 194                         ret = err;
 195         }
 196
 197         return ret;
 198 }
 199 EXPORT_SYMBOL_GPL(ndo_dflt_netdev_switch_port_bridge_setlink);
 200
 201 /**
 202  *      ndo_dflt_netdev_switch_port_bridge_dellink - default ndo bridge dellink
 203  *                                                   op for master devices
 204  *
 205  *      @dev: port device
 206  *      @nlh: netlink msg with bridge port attributes
 207  *      @flags: bridge dellink flags
 208  *
 209  *      Notify master device slaves of bridge port attribute deletes
 210  */
 211 int ndo_dflt_netdev_switch_port_bridge_dellink(struct net_device *dev,
 212                                                struct nlmsghdr *nlh, u16 flags)
 213 {
 214         struct net_device *lower_dev;
 215         struct list_head *iter;
 216         int ret = 0, err = 0;
 217
 218         if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
 219                 return ret;
 220
 221         netdev_for_each_lower_dev(dev, lower_dev, iter) {
 222                 err = netdev_switch_port_bridge_dellink(lower_dev, nlh, flags);
 223                 if (err && err != -EOPNOTSUPP)
 224                         ret = err;
 225         }
 226
 227         return ret;
 228 }
 229 EXPORT_SYMBOL_GPL(ndo_dflt_netdev_switch_port_bridge_dellink);
 230
 231 static struct net_device *netdev_switch_get_lowest_dev(struct net_device *dev)
 232 {
 233         const struct net_device_ops *ops = dev->netdev_ops;
 234         struct net_device *lower_dev;
 235         struct net_device *port_dev;
 236         struct list_head *iter;
 237
 238         /* Recusively search down until we find a sw port dev.
 239          * (A sw port dev supports ndo_switch_parent_id_get).
 240          */
 241
 242         if (dev->features & NETIF_F_HW_SWITCH_OFFLOAD &&
 243             ops->ndo_switch_parent_id_get)
 244                 return dev;
 245
 246         netdev_for_each_lower_dev(dev, lower_dev, iter) {
 247                 port_dev = netdev_switch_get_lowest_dev(lower_dev);
 248                 if (port_dev)
 249                         return port_dev;
 250         }
 251
 252         return NULL;
 253 }
 254
 255 static struct net_device *netdev_switch_get_dev_by_nhs(struct fib_info *fi)
 256 {
 257         struct netdev_phys_item_id psid;
 258         struct netdev_phys_item_id prev_psid;
 259         struct net_device *dev = NULL;
 260         int nhsel;
 261
 262         /* For this route, all nexthop devs must be on the same switch. */
 263
 264         for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
 265                 const struct fib_nh *nh = &fi->fib_nh[nhsel];
 266
 267                 if (!nh->nh_dev)
 268                         return NULL;
 269
 270                 dev = netdev_switch_get_lowest_dev(nh->nh_dev);
 271                 if (!dev)
 272                         return NULL;
 273
 274                 if (netdev_switch_parent_id_get(dev, &psid))
 275                         return NULL;
 276
 277                 if (nhsel > 0) {
 278                         if (prev_psid.id_len != psid.id_len)
 279                                 return NULL;
 280                         if (memcmp(prev_psid.id, psid.id, psid.id_len))
 281                                 return NULL;
 282                 }
 283
 284                 prev_psid = psid;
 285         }
 286
 287         return dev;
 288 }
 289
 290 /**
 291  *      netdev_switch_fib_ipv4_add - Add IPv4 route entry to switch
 292  *
 293  *      @dst: route's IPv4 destination address
 294  *      @dst_len: destination address length (prefix length)
 295  *      @fi: route FIB info structure
 296  *      @tos: route TOS
 297  *      @type: route type
 298  *      @nlflags: netlink flags passed in (NLM_F_*)
 299  *      @tb_id: route table ID
 300  *
 301  *      Add IPv4 route entry to switch device.
 302  */
 303 int netdev_switch_fib_ipv4_add(u32 dst, int dst_len, struct fib_info *fi,
 304                                u8 tos, u8 type, u32 nlflags, u32 tb_id)
 305 {
 306         struct net_device *dev;
 307         const struct net_device_ops *ops;
 308         int err = 0;
 309
 310         /* Don't offload route if using custom ip rules or if
 311          * IPv4 FIB offloading has been disabled completely.
 312          */
 313
 314 #ifdef CONFIG_IP_MULTIPLE_TABLES
 315         if (fi->fib_net->ipv4.fib_has_custom_rules)
 316                 return 0;
 317 #endif
 318
 319         if (fi->fib_net->ipv4.fib_offload_disabled)
 320                 return 0;
 321
 322         dev = netdev_switch_get_dev_by_nhs(fi);
 323         if (!dev)
 324                 return 0;
 325         ops = dev->netdev_ops;
 326
 327         if (ops->ndo_switch_fib_ipv4_add) {
 328                 err = ops->ndo_switch_fib_ipv4_add(dev, htonl(dst), dst_len,
 329                                                    fi, tos, type, nlflags,
 330                                                    tb_id);
 331                 if (!err)
 332                         fi->fib_flags |= RTNH_F_EXTERNAL;
 333         }
 334
 335         return err;
 336 }
 337 EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_add);
 338
 339 /**
 340  *      netdev_switch_fib_ipv4_del - Delete IPv4 route entry from switch
 341  *
 342  *      @dst: route's IPv4 destination address
 343  *      @dst_len: destination address length (prefix length)
 344  *      @fi: route FIB info structure
 345  *      @tos: route TOS
 346  *      @type: route type
 347  *      @tb_id: route table ID
 348  *
 349  *      Delete IPv4 route entry from switch device.
 350  */
 351 int netdev_switch_fib_ipv4_del(u32 dst, int dst_len, struct fib_info *fi,
 352                                u8 tos, u8 type, u32 tb_id)
 353 {
 354         struct net_device *dev;
 355         const struct net_device_ops *ops;
 356         int err = 0;
 357
 358         if (!(fi->fib_flags & RTNH_F_EXTERNAL))
 359                 return 0;
 360
 361         dev = netdev_switch_get_dev_by_nhs(fi);
 362         if (!dev)
 363                 return 0;
 364         ops = dev->netdev_ops;
 365
 366         if (ops->ndo_switch_fib_ipv4_del) {
 367                 err = ops->ndo_switch_fib_ipv4_del(dev, htonl(dst), dst_len,
 368                                                    fi, tos, type, tb_id);
 369                 if (!err)
 370                         fi->fib_flags &= ~RTNH_F_EXTERNAL;
 371         }
 372
 373         return err;
 374 }
 375 EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_del);
 376
 377 /**
 378  *      netdev_switch_fib_ipv4_abort - Abort an IPv4 FIB operation
 379  *
 380  *      @fi: route FIB info structure
 381  */
 382 void netdev_switch_fib_ipv4_abort(struct fib_info *fi)
 383 {
 384         /* There was a problem installing this route to the offload
 385          * device.  For now, until we come up with more refined
 386          * policy handling, abruptly end IPv4 fib offloading for
 387          * for entire net by flushing offload device(s) of all
 388          * IPv4 routes, and mark IPv4 fib offloading broken from
 389          * this point forward.
 390          */
 391
 392         fib_flush_external(fi->fib_net);
 393         fi->fib_net->ipv4.fib_offload_disabled = true;
 394 }
 395 EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_abort);