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/workqueue.h>
  39 #include <net/arp.h>
  40 #include <net/neighbour.h>
  41 #include <net/route.h>
  42 #include <net/netevent.h>
  43 #include <net/addrconf.h>
  44 #include <net/ip6_route.h>
  45 #include <rdma/ib_addr.h>
  46
  47 MODULE_AUTHOR("Sean Hefty");
  48 MODULE_DESCRIPTION("IB Address Translation");
  49 MODULE_LICENSE("Dual BSD/GPL");
  50
  51 struct addr_req {
  52         struct list_head list;
  53         struct sockaddr_storage src_addr;
  54         struct sockaddr_storage dst_addr;
  55         struct rdma_dev_addr *addr;
  56         struct rdma_addr_client *client;
  57         void *context;
  58         void (*callback)(int status, struct sockaddr *src_addr,
  59                          struct rdma_dev_addr *addr, void *context);
  60         unsigned long timeout;
  61         int status;
  62 };
  63
  64 static void process_req(struct work_struct *work);
  65
  66 static DEFINE_MUTEX(lock);
  67 static LIST_HEAD(req_list);
  68 static DECLARE_DELAYED_WORK(work, process_req);
  69 static struct workqueue_struct *addr_wq;
  70
  71 void rdma_addr_register_client(struct rdma_addr_client *client)
  72 {
  73         atomic_set(&client->refcount, 1);
  74         init_completion(&client->comp);
  75 }
  76 EXPORT_SYMBOL(rdma_addr_register_client);
  77
  78 static inline void put_client(struct rdma_addr_client *client)
  79 {
  80         if (atomic_dec_and_test(&client->refcount))
  81                 complete(&client->comp);
  82 }
  83
  84 void rdma_addr_unregister_client(struct rdma_addr_client *client)
  85 {
  86         put_client(client);
  87         wait_for_completion(&client->comp);
  88 }
  89 EXPORT_SYMBOL(rdma_addr_unregister_client);
  90
  91 int rdma_copy_addr(struct rdma_dev_addr *dev_addr, struct net_device *dev,
  92                      const unsigned char *dst_dev_addr)
  93 {
  94         dev_addr->dev_type = dev->type;
  95         memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
  96         memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
  97         if (dst_dev_addr)
  98                 memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
  99         dev_addr->bound_dev_if = dev->ifindex;
 100         return 0;
 101 }
 102 EXPORT_SYMBOL(rdma_copy_addr);
 103
 104 int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
 105 {
 106         struct net_device *dev;
 107         int ret = -EADDRNOTAVAIL;
 108
 109         if (dev_addr->bound_dev_if) {
 110                 dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if);
 111                 if (!dev)
 112                         return -ENODEV;
 113                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 114                 dev_put(dev);
 115                 return ret;
 116         }
 117
 118         switch (addr->sa_family) {
 119         case AF_INET:
 120                 dev = ip_dev_find(&init_net,
 121                         ((struct sockaddr_in *) addr)->sin_addr.s_addr);
 122
 123                 if (!dev)
 124                         return ret;
 125
 126                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 127                 dev_put(dev);
 128                 break;
 129
 130 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 131         case AF_INET6:
 132                 read_lock(&dev_base_lock);
 133                 for_each_netdev(&init_net, dev) {
 134                         if (ipv6_chk_addr(&init_net,
 135                                           &((struct sockaddr_in6 *) addr)->sin6_addr,
 136                                           dev, 1)) {
 137                                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 138                                 break;
 139                         }
 140                 }
 141                 read_unlock(&dev_base_lock);
 142                 break;
 143 #endif
 144         }
 145         return ret;
 146 }
 147 EXPORT_SYMBOL(rdma_translate_ip);
 148
 149 static void set_timeout(unsigned long time)
 150 {
 151         unsigned long delay;
 152
 153         cancel_delayed_work(&work);
 154
 155         delay = time - jiffies;
 156         if ((long)delay <= 0)
 157                 delay = 1;
 158
 159         queue_delayed_work(addr_wq, &work, delay);
 160 }
 161
 162 static void queue_req(struct addr_req *req)
 163 {
 164         struct addr_req *temp_req;
 165
 166         mutex_lock(&lock);
 167         list_for_each_entry_reverse(temp_req, &req_list, list) {
 168                 if (time_after_eq(req->timeout, temp_req->timeout))
 169                         break;
 170         }
 171
 172         list_add(&req->list, &temp_req->list);
 173
 174         if (req_list.next == &req->list)
 175                 set_timeout(req->timeout);
 176         mutex_unlock(&lock);
 177 }
 178
 179 static int addr4_resolve(struct sockaddr_in *src_in,
 180                          struct sockaddr_in *dst_in,
 181                          struct rdma_dev_addr *addr)
 182 {
 183         __be32 src_ip = src_in->sin_addr.s_addr;
 184         __be32 dst_ip = dst_in->sin_addr.s_addr;
 185         struct flowi fl;
 186         struct rtable *rt;
 187         struct neighbour *neigh;
 188         int ret;
 189
 190         memset(&fl, 0, sizeof fl);
 191         fl.nl_u.ip4_u.daddr = dst_ip;
 192         fl.nl_u.ip4_u.saddr = src_ip;
 193         fl.oif = addr->bound_dev_if;
 194
 195         ret = ip_route_output_key(&init_net, &rt, &fl);
 196         if (ret)
 197                 goto out;
 198
 199         src_in->sin_family = AF_INET;
 200         src_in->sin_addr.s_addr = rt->rt_src;
 201
 202         if (rt->idev->dev->flags & IFF_LOOPBACK) {
 203                 ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
 204                 if (!ret)
 205                         memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
 206                 goto put;
 207         }
 208
 209         /* If the device does ARP internally, return 'done' */
 210         if (rt->idev->dev->flags & IFF_NOARP) {
 211                 rdma_copy_addr(addr, rt->idev->dev, NULL);
 212                 goto put;
 213         }
 214
 215         neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, rt->idev->dev);
 216         if (!neigh || !(neigh->nud_state & NUD_VALID)) {
 217                 neigh_event_send(rt->u.dst.neighbour, NULL);
 218                 ret = -ENODATA;
 219                 if (neigh)
 220                         goto release;
 221                 goto put;
 222         }
 223
 224         ret = rdma_copy_addr(addr, neigh->dev, neigh->ha);
 225 release:
 226         neigh_release(neigh);
 227 put:
 228         ip_rt_put(rt);
 229 out:
 230         return ret;
 231 }
 232
 233 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 234 static int addr6_resolve(struct sockaddr_in6 *src_in,
 235                          struct sockaddr_in6 *dst_in,
 236                          struct rdma_dev_addr *addr)
 237 {
 238         struct flowi fl;
 239         struct neighbour *neigh;
 240         struct dst_entry *dst;
 241         int ret;
 242
 243         memset(&fl, 0, sizeof fl);
 244         ipv6_addr_copy(&fl.fl6_dst, &dst_in->sin6_addr);
 245         ipv6_addr_copy(&fl.fl6_src, &src_in->sin6_addr);
 246         fl.oif = addr->bound_dev_if;
 247
 248         dst = ip6_route_output(&init_net, NULL, &fl);
 249         if ((ret = dst->error))
 250                 goto put;
 251
 252         if (ipv6_addr_any(&fl.fl6_src)) {
 253                 ret = ipv6_dev_get_saddr(&init_net, ip6_dst_idev(dst)->dev,
 254                                          &fl.fl6_dst, 0, &fl.fl6_src);
 255                 if (ret)
 256                         goto put;
 257
 258                 src_in->sin6_family = AF_INET6;
 259                 ipv6_addr_copy(&src_in->sin6_addr, &fl.fl6_src);
 260         }
 261
 262         if (dst->dev->flags & IFF_LOOPBACK) {
 263                 ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
 264                 if (!ret)
 265                         memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
 266                 goto put;
 267         }
 268
 269         /* If the device does ARP internally, return 'done' */
 270         if (dst->dev->flags & IFF_NOARP) {
 271                 ret = rdma_copy_addr(addr, dst->dev, NULL);
 272                 goto put;
 273         }
 274
 275         neigh = dst->neighbour;
 276         if (!neigh || !(neigh->nud_state & NUD_VALID)) {
 277                 neigh_event_send(dst->neighbour, NULL);
 278                 ret = -ENODATA;
 279                 goto put;
 280         }
 281
 282         ret = rdma_copy_addr(addr, dst->dev, neigh->ha);
 283 put:
 284         dst_release(dst);
 285         return ret;
 286 }
 287 #else
 288 static int addr6_resolve(struct sockaddr_in6 *src_in,
 289                          struct sockaddr_in6 *dst_in,
 290                          struct rdma_dev_addr *addr)
 291 {
 292         return -EADDRNOTAVAIL;
 293 }
 294 #endif
 295
 296 static int addr_resolve(struct sockaddr *src_in,
 297                         struct sockaddr *dst_in,
 298                         struct rdma_dev_addr *addr)
 299 {
 300         if (src_in->sa_family == AF_INET) {
 301                 return addr4_resolve((struct sockaddr_in *) src_in,
 302                         (struct sockaddr_in *) dst_in, addr);
 303         } else
 304                 return addr6_resolve((struct sockaddr_in6 *) src_in,
 305                         (struct sockaddr_in6 *) dst_in, addr);
 306 }
 307
 308 static void process_req(struct work_struct *work)
 309 {
 310         struct addr_req *req, *temp_req;
 311         struct sockaddr *src_in, *dst_in;
 312         struct list_head done_list;
 313
 314         INIT_LIST_HEAD(&done_list);
 315
 316         mutex_lock(&lock);
 317         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 318                 if (req->status == -ENODATA) {
 319                         src_in = (struct sockaddr *) &req->src_addr;
 320                         dst_in = (struct sockaddr *) &req->dst_addr;
 321                         req->status = addr_resolve(src_in, dst_in, req->addr);
 322                         if (req->status && time_after_eq(jiffies, req->timeout))
 323                                 req->status = -ETIMEDOUT;
 324                         else if (req->status == -ENODATA)
 325                                 continue;
 326                 }
 327                 list_move_tail(&req->list, &done_list);
 328         }
 329
 330         if (!list_empty(&req_list)) {
 331                 req = list_entry(req_list.next, struct addr_req, list);
 332                 set_timeout(req->timeout);
 333         }
 334         mutex_unlock(&lock);
 335
 336         list_for_each_entry_safe(req, temp_req, &done_list, list) {
 337                 list_del(&req->list);
 338                 req->callback(req->status, (struct sockaddr *) &req->src_addr,
 339                         req->addr, req->context);
 340                 put_client(req->client);
 341                 kfree(req);
 342         }
 343 }
 344
 345 int rdma_resolve_ip(struct rdma_addr_client *client,
 346                     struct sockaddr *src_addr, struct sockaddr *dst_addr,
 347                     struct rdma_dev_addr *addr, int timeout_ms,
 348                     void (*callback)(int status, struct sockaddr *src_addr,
 349                                      struct rdma_dev_addr *addr, void *context),
 350                     void *context)
 351 {
 352         struct sockaddr *src_in, *dst_in;
 353         struct addr_req *req;
 354         int ret = 0;
 355
 356         req = kzalloc(sizeof *req, GFP_KERNEL);
 357         if (!req)
 358                 return -ENOMEM;
 359
 360         src_in = (struct sockaddr *) &req->src_addr;
 361         dst_in = (struct sockaddr *) &req->dst_addr;
 362
 363         if (src_addr) {
 364                 if (src_addr->sa_family != dst_addr->sa_family) {
 365                         ret = -EINVAL;
 366                         goto err;
 367                 }
 368
 369                 memcpy(src_in, src_addr, ip_addr_size(src_addr));
 370         } else {
 371                 src_in->sa_family = dst_addr->sa_family;
 372         }
 373
 374         memcpy(dst_in, dst_addr, ip_addr_size(dst_addr));
 375         req->addr = addr;
 376         req->callback = callback;
 377         req->context = context;
 378         req->client = client;
 379         atomic_inc(&client->refcount);
 380
 381         req->status = addr_resolve(src_in, dst_in, addr);
 382         switch (req->status) {
 383         case 0:
 384                 req->timeout = jiffies;
 385                 queue_req(req);
 386                 break;
 387         case -ENODATA:
 388                 req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
 389                 queue_req(req);
 390                 break;
 391         default:
 392                 ret = req->status;
 393                 atomic_dec(&client->refcount);
 394                 goto err;
 395         }
 396         return ret;
 397 err:
 398         kfree(req);
 399         return ret;
 400 }
 401 EXPORT_SYMBOL(rdma_resolve_ip);
 402
 403 void rdma_addr_cancel(struct rdma_dev_addr *addr)
 404 {
 405         struct addr_req *req, *temp_req;
 406
 407         mutex_lock(&lock);
 408         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 409                 if (req->addr == addr) {
 410                         req->status = -ECANCELED;
 411                         req->timeout = jiffies;
 412                         list_move(&req->list, &req_list);
 413                         set_timeout(req->timeout);
 414                         break;
 415                 }
 416         }
 417         mutex_unlock(&lock);
 418 }
 419 EXPORT_SYMBOL(rdma_addr_cancel);
 420
 421 static int netevent_callback(struct notifier_block *self, unsigned long event,
 422         void *ctx)
 423 {
 424         if (event == NETEVENT_NEIGH_UPDATE) {
 425                 struct neighbour *neigh = ctx;
 426
 427                 if (neigh->nud_state & NUD_VALID) {
 428                         set_timeout(jiffies);
 429                 }
 430         }
 431         return 0;
 432 }
 433
 434 static struct notifier_block nb = {
 435         .notifier_call = netevent_callback
 436 };
 437
 438 static int __init addr_init(void)
 439 {
 440         addr_wq = create_singlethread_workqueue("ib_addr");
 441         if (!addr_wq)
 442                 return -ENOMEM;
 443
 444         register_netevent_notifier(&nb);
 445         return 0;
 446 }
 447
 448 static void __exit addr_cleanup(void)
 449 {
 450         unregister_netevent_notifier(&nb);
 451         destroy_workqueue(addr_wq);
 452 }
 453
 454 module_init(addr_init);
 455 module_exit(addr_cleanup);