drivers/infiniband/core/addr.c

   1 /*
   2  * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
   3  * Copyright (c) 2002-2005, Network Appliance, Inc. All rights reserved.
   4  * Copyright (c) 1999-2005, Mellanox Technologies, Inc. All rights reserved.
   5  * Copyright (c) 2005 Intel Corporation.  All rights reserved.
   6  *
   7  * This software is available to you under a choice of one of two
   8  * licenses.  You may choose to be licensed under the terms of the GNU
   9  * General Public License (GPL) Version 2, available from the file
  10  * COPYING in the main directory of this source tree, or the
  11  * OpenIB.org BSD license below:
  12  *
  13  *     Redistribution and use in source and binary forms, with or
  14  *     without modification, are permitted provided that the following
  15  *     conditions are met:
  16  *
  17  *      - Redistributions of source code must retain the above
  18  *        copyright notice, this list of conditions and the following
  19  *        disclaimer.
  20  *
  21  *      - Redistributions in binary form must reproduce the above
  22  *        copyright notice, this list of conditions and the following
  23  *        disclaimer in the documentation and/or other materials
  24  *        provided with the distribution.
  25  *
  26  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  27  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  28  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  29  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  30  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  31  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  32  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  33  * SOFTWARE.
  34  */
  35
  36 #include <linux/mutex.h>
  37 #include <linux/inetdevice.h>
  38 #include <linux/slab.h>
  39 #include <linux/workqueue.h>
  40 #include <net/arp.h>
  41 #include <net/neighbour.h>
  42 #include <net/route.h>
  43 #include <net/netevent.h>
  44 #include <net/addrconf.h>
  45 #include <net/ip6_route.h>
  46 #include <rdma/ib_addr.h>
  47
  48 MODULE_AUTHOR("Sean Hefty");
  49 MODULE_DESCRIPTION("IB Address Translation");
  50 MODULE_LICENSE("Dual BSD/GPL");
  51
  52 struct addr_req {
  53         struct list_head list;
  54         struct sockaddr_storage src_addr;
  55         struct sockaddr_storage dst_addr;
  56         struct rdma_dev_addr *addr;
  57         struct rdma_addr_client *client;
  58         void *context;
  59         void (*callback)(int status, struct sockaddr *src_addr,
  60                          struct rdma_dev_addr *addr, void *context);
  61         unsigned long timeout;
  62         int status;
  63 };
  64
  65 static void process_req(struct work_struct *work);
  66
  67 static DEFINE_MUTEX(lock);
  68 static LIST_HEAD(req_list);
  69 static DECLARE_DELAYED_WORK(work, process_req);
  70 static struct workqueue_struct *addr_wq;
  71
  72 void rdma_addr_register_client(struct rdma_addr_client *client)
  73 {
  74         atomic_set(&client->refcount, 1);
  75         init_completion(&client->comp);
  76 }
  77 EXPORT_SYMBOL(rdma_addr_register_client);
  78
  79 static inline void put_client(struct rdma_addr_client *client)
  80 {
  81         if (atomic_dec_and_test(&client->refcount))
  82                 complete(&client->comp);
  83 }
  84
  85 void rdma_addr_unregister_client(struct rdma_addr_client *client)
  86 {
  87         put_client(client);
  88         wait_for_completion(&client->comp);
  89 }
  90 EXPORT_SYMBOL(rdma_addr_unregister_client);
  91
  92 int rdma_copy_addr(struct rdma_dev_addr *dev_addr, struct net_device *dev,
  93                      const unsigned char *dst_dev_addr)
  94 {
  95         dev_addr->dev_type = dev->type;
  96         memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
  97         memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
  98         if (dst_dev_addr)
  99                 memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
 100         dev_addr->bound_dev_if = dev->ifindex;
 101         return 0;
 102 }
 103 EXPORT_SYMBOL(rdma_copy_addr);
 104
 105 int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
 106 {
 107         struct net_device *dev;
 108         int ret = -EADDRNOTAVAIL;
 109
 110         if (dev_addr->bound_dev_if) {
 111                 dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if);
 112                 if (!dev)
 113                         return -ENODEV;
 114                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 115                 dev_put(dev);
 116                 return ret;
 117         }
 118
 119         switch (addr->sa_family) {
 120         case AF_INET:
 121                 dev = ip_dev_find(&init_net,
 122                         ((struct sockaddr_in *) addr)->sin_addr.s_addr);
 123
 124                 if (!dev)
 125                         return ret;
 126
 127                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 128                 dev_put(dev);
 129                 break;
 130
 131 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 132         case AF_INET6:
 133                 rcu_read_lock();
 134                 for_each_netdev_rcu(&init_net, dev) {
 135                         if (ipv6_chk_addr(&init_net,
 136                                           &((struct sockaddr_in6 *) addr)->sin6_addr,
 137                                           dev, 1)) {
 138                                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 139                                 break;
 140                         }
 141                 }
 142                 rcu_read_unlock();
 143                 break;
 144 #endif
 145         }
 146         return ret;
 147 }
 148 EXPORT_SYMBOL(rdma_translate_ip);
 149
 150 static void set_timeout(unsigned long time)
 151 {
 152         unsigned long delay;
 153
 154         cancel_delayed_work(&work);
 155
 156         delay = time - jiffies;
 157         if ((long)delay <= 0)
 158                 delay = 1;
 159
 160         queue_delayed_work(addr_wq, &work, delay);
 161 }
 162
 163 static void queue_req(struct addr_req *req)
 164 {
 165         struct addr_req *temp_req;
 166
 167         mutex_lock(&lock);
 168         list_for_each_entry_reverse(temp_req, &req_list, list) {
 169                 if (time_after_eq(req->timeout, temp_req->timeout))
 170                         break;
 171         }
 172
 173         list_add(&req->list, &temp_req->list);
 174
 175         if (req_list.next == &req->list)
 176                 set_timeout(req->timeout);
 177         mutex_unlock(&lock);
 178 }
 179
 180 static int addr4_resolve(struct sockaddr_in *src_in,
 181                          struct sockaddr_in *dst_in,
 182                          struct rdma_dev_addr *addr)
 183 {
 184         __be32 src_ip = src_in->sin_addr.s_addr;
 185         __be32 dst_ip = dst_in->sin_addr.s_addr;
 186         struct rtable *rt;
 187         struct neighbour *neigh;
 188         int ret;
 189
 190         rt = ip_route_output(&init_net, dst_ip, src_ip, 0, addr->bound_dev_if);
 191         if (IS_ERR(rt)) {
 192                 ret = PTR_ERR(rt);
 193                 goto out;
 194         }
 195         src_in->sin_family = AF_INET;
 196         src_in->sin_addr.s_addr = rt->rt_src;
 197
 198         if (rt->dst.dev->flags & IFF_LOOPBACK) {
 199                 ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
 200                 if (!ret)
 201                         memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
 202                 goto put;
 203         }
 204
 205         /* If the device does ARP internally, return 'done' */
 206         if (rt->dst.dev->flags & IFF_NOARP) {
 207                 ret = rdma_copy_addr(addr, rt->dst.dev, NULL);
 208                 goto put;
 209         }
 210
 211         neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, rt->dst.dev);
 212         if (!neigh || !(neigh->nud_state & NUD_VALID)) {
 213                 neigh_event_send(rt->dst.neighbour, NULL);
 214                 ret = -ENODATA;
 215                 if (neigh)
 216                         goto release;
 217                 goto put;
 218         }
 219
 220         ret = rdma_copy_addr(addr, neigh->dev, neigh->ha);
 221 release:
 222         neigh_release(neigh);
 223 put:
 224         ip_rt_put(rt);
 225 out:
 226         return ret;
 227 }
 228
 229 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 230 static int addr6_resolve(struct sockaddr_in6 *src_in,
 231                          struct sockaddr_in6 *dst_in,
 232                          struct rdma_dev_addr *addr)
 233 {
 234         struct flowi6 fl6;
 235         struct neighbour *neigh;
 236         struct dst_entry *dst;
 237         int ret;
 238
 239         memset(&fl6, 0, sizeof fl6);
 240         ipv6_addr_copy(&fl6.daddr, &dst_in->sin6_addr);
 241         ipv6_addr_copy(&fl6.saddr, &src_in->sin6_addr);
 242         fl6.flowi6_oif = addr->bound_dev_if;
 243
 244         dst = ip6_route_output(&init_net, NULL, &fl6);
 245         if ((ret = dst->error))
 246                 goto put;
 247
 248         if (ipv6_addr_any(&fl6.saddr)) {
 249                 ret = ipv6_dev_get_saddr(&init_net, ip6_dst_idev(dst)->dev,
 250                                          &fl6.daddr, 0, &fl6.saddr);
 251                 if (ret)
 252                         goto put;
 253
 254                 src_in->sin6_family = AF_INET6;
 255                 ipv6_addr_copy(&src_in->sin6_addr, &fl6.saddr);
 256         }
 257
 258         if (dst->dev->flags & IFF_LOOPBACK) {
 259                 ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
 260                 if (!ret)
 261                         memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
 262                 goto put;
 263         }
 264
 265         /* If the device does ARP internally, return 'done' */
 266         if (dst->dev->flags & IFF_NOARP) {
 267                 ret = rdma_copy_addr(addr, dst->dev, NULL);
 268                 goto put;
 269         }
 270
 271         neigh = dst->neighbour;
 272         if (!neigh || !(neigh->nud_state & NUD_VALID)) {
 273                 neigh_event_send(dst->neighbour, NULL);
 274                 ret = -ENODATA;
 275                 goto put;
 276         }
 277
 278         ret = rdma_copy_addr(addr, dst->dev, neigh->ha);
 279 put:
 280         dst_release(dst);
 281         return ret;
 282 }
 283 #else
 284 static int addr6_resolve(struct sockaddr_in6 *src_in,
 285                          struct sockaddr_in6 *dst_in,
 286                          struct rdma_dev_addr *addr)
 287 {
 288         return -EADDRNOTAVAIL;
 289 }
 290 #endif
 291
 292 static int addr_resolve(struct sockaddr *src_in,
 293                         struct sockaddr *dst_in,
 294                         struct rdma_dev_addr *addr)
 295 {
 296         if (src_in->sa_family == AF_INET) {
 297                 return addr4_resolve((struct sockaddr_in *) src_in,
 298                         (struct sockaddr_in *) dst_in, addr);
 299         } else
 300                 return addr6_resolve((struct sockaddr_in6 *) src_in,
 301                         (struct sockaddr_in6 *) dst_in, addr);
 302 }
 303
 304 static void process_req(struct work_struct *work)
 305 {
 306         struct addr_req *req, *temp_req;
 307         struct sockaddr *src_in, *dst_in;
 308         struct list_head done_list;
 309
 310         INIT_LIST_HEAD(&done_list);
 311
 312         mutex_lock(&lock);
 313         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 314                 if (req->status == -ENODATA) {
 315                         src_in = (struct sockaddr *) &req->src_addr;
 316                         dst_in = (struct sockaddr *) &req->dst_addr;
 317                         req->status = addr_resolve(src_in, dst_in, req->addr);
 318                         if (req->status && time_after_eq(jiffies, req->timeout))
 319                                 req->status = -ETIMEDOUT;
 320                         else if (req->status == -ENODATA)
 321                                 continue;
 322                 }
 323                 list_move_tail(&req->list, &done_list);
 324         }
 325
 326         if (!list_empty(&req_list)) {
 327                 req = list_entry(req_list.next, struct addr_req, list);
 328                 set_timeout(req->timeout);
 329         }
 330         mutex_unlock(&lock);
 331
 332         list_for_each_entry_safe(req, temp_req, &done_list, list) {
 333                 list_del(&req->list);
 334                 req->callback(req->status, (struct sockaddr *) &req->src_addr,
 335                         req->addr, req->context);
 336                 put_client(req->client);
 337                 kfree(req);
 338         }
 339 }
 340
 341 int rdma_resolve_ip(struct rdma_addr_client *client,
 342                     struct sockaddr *src_addr, struct sockaddr *dst_addr,
 343                     struct rdma_dev_addr *addr, int timeout_ms,
 344                     void (*callback)(int status, struct sockaddr *src_addr,
 345                                      struct rdma_dev_addr *addr, void *context),
 346                     void *context)
 347 {
 348         struct sockaddr *src_in, *dst_in;
 349         struct addr_req *req;
 350         int ret = 0;
 351
 352         req = kzalloc(sizeof *req, GFP_KERNEL);
 353         if (!req)
 354                 return -ENOMEM;
 355
 356         src_in = (struct sockaddr *) &req->src_addr;
 357         dst_in = (struct sockaddr *) &req->dst_addr;
 358
 359         if (src_addr) {
 360                 if (src_addr->sa_family != dst_addr->sa_family) {
 361                         ret = -EINVAL;
 362                         goto err;
 363                 }
 364
 365                 memcpy(src_in, src_addr, ip_addr_size(src_addr));
 366         } else {
 367                 src_in->sa_family = dst_addr->sa_family;
 368         }
 369
 370         memcpy(dst_in, dst_addr, ip_addr_size(dst_addr));
 371         req->addr = addr;
 372         req->callback = callback;
 373         req->context = context;
 374         req->client = client;
 375         atomic_inc(&client->refcount);
 376
 377         req->status = addr_resolve(src_in, dst_in, addr);
 378         switch (req->status) {
 379         case 0:
 380                 req->timeout = jiffies;
 381                 queue_req(req);
 382                 break;
 383         case -ENODATA:
 384                 req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
 385                 queue_req(req);
 386                 break;
 387         default:
 388                 ret = req->status;
 389                 atomic_dec(&client->refcount);
 390                 goto err;
 391         }
 392         return ret;
 393 err:
 394         kfree(req);
 395         return ret;
 396 }
 397 EXPORT_SYMBOL(rdma_resolve_ip);
 398
 399 void rdma_addr_cancel(struct rdma_dev_addr *addr)
 400 {
 401         struct addr_req *req, *temp_req;
 402
 403         mutex_lock(&lock);
 404         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 405                 if (req->addr == addr) {
 406                         req->status = -ECANCELED;
 407                         req->timeout = jiffies;
 408                         list_move(&req->list, &req_list);
 409                         set_timeout(req->timeout);
 410                         break;
 411                 }
 412         }
 413         mutex_unlock(&lock);
 414 }
 415 EXPORT_SYMBOL(rdma_addr_cancel);
 416
 417 static int netevent_callback(struct notifier_block *self, unsigned long event,
 418         void *ctx)
 419 {
 420         if (event == NETEVENT_NEIGH_UPDATE) {
 421                 struct neighbour *neigh = ctx;
 422
 423                 if (neigh->nud_state & NUD_VALID) {
 424                         set_timeout(jiffies);
 425                 }
 426         }
 427         return 0;
 428 }
 429
 430 static struct notifier_block nb = {
 431         .notifier_call = netevent_callback
 432 };
 433
 434 static int __init addr_init(void)
 435 {
 436         addr_wq = create_singlethread_workqueue("ib_addr");
 437         if (!addr_wq)
 438                 return -ENOMEM;
 439
 440         register_netevent_notifier(&nb);
 441         return 0;
 442 }
 443
 444 static void __exit addr_cleanup(void)
 445 {
 446         unregister_netevent_notifier(&nb);
 447         destroy_workqueue(addr_wq);
 448 }
 449
 450 module_init(addr_init);
 451 module_exit(addr_cleanup);