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 <linux/module.h>
  41 #include <net/arp.h>
  42 #include <net/neighbour.h>
  43 #include <net/route.h>
  44 #include <net/netevent.h>
  45 #include <net/addrconf.h>
  46 #include <net/ip6_route.h>
  47 #include <rdma/ib_addr.h>
  48
  49 MODULE_AUTHOR("Sean Hefty");
  50 MODULE_DESCRIPTION("IB Address Translation");
  51 MODULE_LICENSE("Dual BSD/GPL");
  52
  53 struct addr_req {
  54         struct list_head list;
  55         struct sockaddr_storage src_addr;
  56         struct sockaddr_storage dst_addr;
  57         struct rdma_dev_addr *addr;
  58         struct rdma_addr_client *client;
  59         void *context;
  60         void (*callback)(int status, struct sockaddr *src_addr,
  61                          struct rdma_dev_addr *addr, void *context);
  62         unsigned long timeout;
  63         int status;
  64 };
  65
  66 static void process_req(struct work_struct *work);
  67
  68 static DEFINE_MUTEX(lock);
  69 static LIST_HEAD(req_list);
  70 static DECLARE_DELAYED_WORK(work, process_req);
  71 static struct workqueue_struct *addr_wq;
  72
  73 void rdma_addr_register_client(struct rdma_addr_client *client)
  74 {
  75         atomic_set(&client->refcount, 1);
  76         init_completion(&client->comp);
  77 }
  78 EXPORT_SYMBOL(rdma_addr_register_client);
  79
  80 static inline void put_client(struct rdma_addr_client *client)
  81 {
  82         if (atomic_dec_and_test(&client->refcount))
  83                 complete(&client->comp);
  84 }
  85
  86 void rdma_addr_unregister_client(struct rdma_addr_client *client)
  87 {
  88         put_client(client);
  89         wait_for_completion(&client->comp);
  90 }
  91 EXPORT_SYMBOL(rdma_addr_unregister_client);
  92
  93 int rdma_copy_addr(struct rdma_dev_addr *dev_addr, struct net_device *dev,
  94                      const unsigned char *dst_dev_addr)
  95 {
  96         dev_addr->dev_type = dev->type;
  97         memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
  98         memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
  99         if (dst_dev_addr)
 100                 memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
 101         dev_addr->bound_dev_if = dev->ifindex;
 102         return 0;
 103 }
 104 EXPORT_SYMBOL(rdma_copy_addr);
 105
 106 int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
 107 {
 108         struct net_device *dev;
 109         int ret = -EADDRNOTAVAIL;
 110
 111         if (dev_addr->bound_dev_if) {
 112                 dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if);
 113                 if (!dev)
 114                         return -ENODEV;
 115                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 116                 dev_put(dev);
 117                 return ret;
 118         }
 119
 120         switch (addr->sa_family) {
 121         case AF_INET:
 122                 dev = ip_dev_find(&init_net,
 123                         ((struct sockaddr_in *) addr)->sin_addr.s_addr);
 124
 125                 if (!dev)
 126                         return ret;
 127
 128                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 129                 dev_put(dev);
 130                 break;
 131
 132 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 133         case AF_INET6:
 134                 rcu_read_lock();
 135                 for_each_netdev_rcu(&init_net, dev) {
 136                         if (ipv6_chk_addr(&init_net,
 137                                           &((struct sockaddr_in6 *) addr)->sin6_addr,
 138                                           dev, 1)) {
 139                                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 140                                 break;
 141                         }
 142                 }
 143                 rcu_read_unlock();
 144                 break;
 145 #endif
 146         }
 147         return ret;
 148 }
 149 EXPORT_SYMBOL(rdma_translate_ip);
 150
 151 static void set_timeout(unsigned long time)
 152 {
 153         unsigned long delay;
 154
 155         cancel_delayed_work(&work);
 156
 157         delay = time - jiffies;
 158         if ((long)delay <= 0)
 159                 delay = 1;
 160
 161         queue_delayed_work(addr_wq, &work, delay);
 162 }
 163
 164 static void queue_req(struct addr_req *req)
 165 {
 166         struct addr_req *temp_req;
 167
 168         mutex_lock(&lock);
 169         list_for_each_entry_reverse(temp_req, &req_list, list) {
 170                 if (time_after_eq(req->timeout, temp_req->timeout))
 171                         break;
 172         }
 173
 174         list_add(&req->list, &temp_req->list);
 175
 176         if (req_list.next == &req->list)
 177                 set_timeout(req->timeout);
 178         mutex_unlock(&lock);
 179 }
 180
 181 static int dst_fetch_ha(struct dst_entry *dst, struct rdma_dev_addr *addr)
 182 {
 183         struct neighbour *n;
 184         int ret;
 185
 186         rcu_read_lock();
 187         n = dst_get_neighbour_noref(dst);
 188         if (!n || !(n->nud_state & NUD_VALID)) {
 189                 if (n)
 190                         neigh_event_send(n, NULL);
 191                 ret = -ENODATA;
 192         } else {
 193                 ret = rdma_copy_addr(addr, dst->dev, n->ha);
 194         }
 195         rcu_read_unlock();
 196
 197         return ret;
 198 }
 199
 200 static int addr4_resolve(struct sockaddr_in *src_in,
 201                          struct sockaddr_in *dst_in,
 202                          struct rdma_dev_addr *addr)
 203 {
 204         __be32 src_ip = src_in->sin_addr.s_addr;
 205         __be32 dst_ip = dst_in->sin_addr.s_addr;
 206         struct rtable *rt;
 207         struct flowi4 fl4;
 208         int ret;
 209
 210         memset(&fl4, 0, sizeof(fl4));
 211         fl4.daddr = dst_ip;
 212         fl4.saddr = src_ip;
 213         fl4.flowi4_oif = addr->bound_dev_if;
 214         rt = ip_route_output_key(&init_net, &fl4);
 215         if (IS_ERR(rt)) {
 216                 ret = PTR_ERR(rt);
 217                 goto out;
 218         }
 219         src_in->sin_family = AF_INET;
 220         src_in->sin_addr.s_addr = fl4.saddr;
 221
 222         if (rt->dst.dev->flags & IFF_LOOPBACK) {
 223                 ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
 224                 if (!ret)
 225                         memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
 226                 goto put;
 227         }
 228
 229         /* If the device does ARP internally, return 'done' */
 230         if (rt->dst.dev->flags & IFF_NOARP) {
 231                 ret = rdma_copy_addr(addr, rt->dst.dev, NULL);
 232                 goto put;
 233         }
 234
 235         ret = dst_fetch_ha(&rt->dst, addr);
 236 put:
 237         ip_rt_put(rt);
 238 out:
 239         return ret;
 240 }
 241
 242 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 243 static int addr6_resolve(struct sockaddr_in6 *src_in,
 244                          struct sockaddr_in6 *dst_in,
 245                          struct rdma_dev_addr *addr)
 246 {
 247         struct flowi6 fl6;
 248         struct dst_entry *dst;
 249         int ret;
 250
 251         memset(&fl6, 0, sizeof fl6);
 252         fl6.daddr = dst_in->sin6_addr;
 253         fl6.saddr = src_in->sin6_addr;
 254         fl6.flowi6_oif = addr->bound_dev_if;
 255
 256         dst = ip6_route_output(&init_net, NULL, &fl6);
 257         if ((ret = dst->error))
 258                 goto put;
 259
 260         if (ipv6_addr_any(&fl6.saddr)) {
 261                 ret = ipv6_dev_get_saddr(&init_net, ip6_dst_idev(dst)->dev,
 262                                          &fl6.daddr, 0, &fl6.saddr);
 263                 if (ret)
 264                         goto put;
 265
 266                 src_in->sin6_family = AF_INET6;
 267                 src_in->sin6_addr = fl6.saddr;
 268         }
 269
 270         if (dst->dev->flags & IFF_LOOPBACK) {
 271                 ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
 272                 if (!ret)
 273                         memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
 274                 goto put;
 275         }
 276
 277         /* If the device does ARP internally, return 'done' */
 278         if (dst->dev->flags & IFF_NOARP) {
 279                 ret = rdma_copy_addr(addr, dst->dev, NULL);
 280                 goto put;
 281         }
 282
 283         ret = dst_fetch_ha(dst, addr);
 284 put:
 285         dst_release(dst);
 286         return ret;
 287 }
 288 #else
 289 static int addr6_resolve(struct sockaddr_in6 *src_in,
 290                          struct sockaddr_in6 *dst_in,
 291                          struct rdma_dev_addr *addr)
 292 {
 293         return -EADDRNOTAVAIL;
 294 }
 295 #endif
 296
 297 static int addr_resolve(struct sockaddr *src_in,
 298                         struct sockaddr *dst_in,
 299                         struct rdma_dev_addr *addr)
 300 {
 301         if (src_in->sa_family == AF_INET) {
 302                 return addr4_resolve((struct sockaddr_in *) src_in,
 303                         (struct sockaddr_in *) dst_in, addr);
 304         } else
 305                 return addr6_resolve((struct sockaddr_in6 *) src_in,
 306                         (struct sockaddr_in6 *) dst_in, addr);
 307 }
 308
 309 static void process_req(struct work_struct *work)
 310 {
 311         struct addr_req *req, *temp_req;
 312         struct sockaddr *src_in, *dst_in;
 313         struct list_head done_list;
 314
 315         INIT_LIST_HEAD(&done_list);
 316
 317         mutex_lock(&lock);
 318         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 319                 if (req->status == -ENODATA) {
 320                         src_in = (struct sockaddr *) &req->src_addr;
 321                         dst_in = (struct sockaddr *) &req->dst_addr;
 322                         req->status = addr_resolve(src_in, dst_in, req->addr);
 323                         if (req->status && time_after_eq(jiffies, req->timeout))
 324                                 req->status = -ETIMEDOUT;
 325                         else if (req->status == -ENODATA)
 326                                 continue;
 327                 }
 328                 list_move_tail(&req->list, &done_list);
 329         }
 330
 331         if (!list_empty(&req_list)) {
 332                 req = list_entry(req_list.next, struct addr_req, list);
 333                 set_timeout(req->timeout);
 334         }
 335         mutex_unlock(&lock);
 336
 337         list_for_each_entry_safe(req, temp_req, &done_list, list) {
 338                 list_del(&req->list);
 339                 req->callback(req->status, (struct sockaddr *) &req->src_addr,
 340                         req->addr, req->context);
 341                 put_client(req->client);
 342                 kfree(req);
 343         }
 344 }
 345
 346 int rdma_resolve_ip(struct rdma_addr_client *client,
 347                     struct sockaddr *src_addr, struct sockaddr *dst_addr,
 348                     struct rdma_dev_addr *addr, int timeout_ms,
 349                     void (*callback)(int status, struct sockaddr *src_addr,
 350                                      struct rdma_dev_addr *addr, void *context),
 351                     void *context)
 352 {
 353         struct sockaddr *src_in, *dst_in;
 354         struct addr_req *req;
 355         int ret = 0;
 356
 357         req = kzalloc(sizeof *req, GFP_KERNEL);
 358         if (!req)
 359                 return -ENOMEM;
 360
 361         src_in = (struct sockaddr *) &req->src_addr;
 362         dst_in = (struct sockaddr *) &req->dst_addr;
 363
 364         if (src_addr) {
 365                 if (src_addr->sa_family != dst_addr->sa_family) {
 366                         ret = -EINVAL;
 367                         goto err;
 368                 }
 369
 370                 memcpy(src_in, src_addr, ip_addr_size(src_addr));
 371         } else {
 372                 src_in->sa_family = dst_addr->sa_family;
 373         }
 374
 375         memcpy(dst_in, dst_addr, ip_addr_size(dst_addr));
 376         req->addr = addr;
 377         req->callback = callback;
 378         req->context = context;
 379         req->client = client;
 380         atomic_inc(&client->refcount);
 381
 382         req->status = addr_resolve(src_in, dst_in, addr);
 383         switch (req->status) {
 384         case 0:
 385                 req->timeout = jiffies;
 386                 queue_req(req);
 387                 break;
 388         case -ENODATA:
 389                 req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
 390                 queue_req(req);
 391                 break;
 392         default:
 393                 ret = req->status;
 394                 atomic_dec(&client->refcount);
 395                 goto err;
 396         }
 397         return ret;
 398 err:
 399         kfree(req);
 400         return ret;
 401 }
 402 EXPORT_SYMBOL(rdma_resolve_ip);
 403
 404 void rdma_addr_cancel(struct rdma_dev_addr *addr)
 405 {
 406         struct addr_req *req, *temp_req;
 407
 408         mutex_lock(&lock);
 409         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 410                 if (req->addr == addr) {
 411                         req->status = -ECANCELED;
 412                         req->timeout = jiffies;
 413                         list_move(&req->list, &req_list);
 414                         set_timeout(req->timeout);
 415                         break;
 416                 }
 417         }
 418         mutex_unlock(&lock);
 419 }
 420 EXPORT_SYMBOL(rdma_addr_cancel);
 421
 422 static int netevent_callback(struct notifier_block *self, unsigned long event,
 423         void *ctx)
 424 {
 425         if (event == NETEVENT_NEIGH_UPDATE) {
 426                 struct neighbour *neigh = ctx;
 427
 428                 if (neigh->nud_state & NUD_VALID) {
 429                         set_timeout(jiffies);
 430                 }
 431         }
 432         return 0;
 433 }
 434
 435 static struct notifier_block nb = {
 436         .notifier_call = netevent_callback
 437 };
 438
 439 static int __init addr_init(void)
 440 {
 441         addr_wq = create_singlethread_workqueue("ib_addr");
 442         if (!addr_wq)
 443                 return -ENOMEM;
 444
 445         register_netevent_notifier(&nb);
 446         return 0;
 447 }
 448
 449 static void __exit addr_cleanup(void)
 450 {
 451         unregister_netevent_notifier(&nb);
 452         destroy_workqueue(addr_wq);
 453 }
 454
 455 module_init(addr_init);
 456 module_exit(addr_cleanup);