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 #include <rdma/ib.h>
  49
  50 MODULE_AUTHOR("Sean Hefty");
  51 MODULE_DESCRIPTION("IB Address Translation");
  52 MODULE_LICENSE("Dual BSD/GPL");
  53
  54 struct addr_req {
  55         struct list_head list;
  56         struct sockaddr_storage src_addr;
  57         struct sockaddr_storage dst_addr;
  58         struct rdma_dev_addr *addr;
  59         struct rdma_addr_client *client;
  60         void *context;
  61         void (*callback)(int status, struct sockaddr *src_addr,
  62                          struct rdma_dev_addr *addr, void *context);
  63         unsigned long timeout;
  64         int status;
  65 };
  66
  67 static void process_req(struct work_struct *work);
  68
  69 static DEFINE_MUTEX(lock);
  70 static LIST_HEAD(req_list);
  71 static DECLARE_DELAYED_WORK(work, process_req);
  72 static struct workqueue_struct *addr_wq;
  73
  74 int rdma_addr_size(struct sockaddr *addr)
  75 {
  76         switch (addr->sa_family) {
  77         case AF_INET:
  78                 return sizeof(struct sockaddr_in);
  79         case AF_INET6:
  80                 return sizeof(struct sockaddr_in6);
  81         case AF_IB:
  82                 return sizeof(struct sockaddr_ib);
  83         default:
  84                 return 0;
  85         }
  86 }
  87 EXPORT_SYMBOL(rdma_addr_size);
  88
  89 void rdma_addr_register_client(struct rdma_addr_client *client)
  90 {
  91         atomic_set(&client->refcount, 1);
  92         init_completion(&client->comp);
  93 }
  94 EXPORT_SYMBOL(rdma_addr_register_client);
  95
  96 static inline void put_client(struct rdma_addr_client *client)
  97 {
  98         if (atomic_dec_and_test(&client->refcount))
  99                 complete(&client->comp);
 100 }
 101
 102 void rdma_addr_unregister_client(struct rdma_addr_client *client)
 103 {
 104         put_client(client);
 105         wait_for_completion(&client->comp);
 106 }
 107 EXPORT_SYMBOL(rdma_addr_unregister_client);
 108
 109 int rdma_copy_addr(struct rdma_dev_addr *dev_addr, struct net_device *dev,
 110                      const unsigned char *dst_dev_addr)
 111 {
 112         dev_addr->dev_type = dev->type;
 113         memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
 114         memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
 115         if (dst_dev_addr)
 116                 memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
 117         dev_addr->bound_dev_if = dev->ifindex;
 118         return 0;
 119 }
 120 EXPORT_SYMBOL(rdma_copy_addr);
 121
 122 int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
 123 {
 124         struct net_device *dev;
 125         int ret = -EADDRNOTAVAIL;
 126
 127         if (dev_addr->bound_dev_if) {
 128                 dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if);
 129                 if (!dev)
 130                         return -ENODEV;
 131                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 132                 dev_put(dev);
 133                 return ret;
 134         }
 135
 136         switch (addr->sa_family) {
 137         case AF_INET:
 138                 dev = ip_dev_find(&init_net,
 139                         ((struct sockaddr_in *) addr)->sin_addr.s_addr);
 140
 141                 if (!dev)
 142                         return ret;
 143
 144                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 145                 dev_put(dev);
 146                 break;
 147
 148 #if IS_ENABLED(CONFIG_IPV6)
 149         case AF_INET6:
 150                 rcu_read_lock();
 151                 for_each_netdev_rcu(&init_net, dev) {
 152                         if (ipv6_chk_addr(&init_net,
 153                                           &((struct sockaddr_in6 *) addr)->sin6_addr,
 154                                           dev, 1)) {
 155                                 ret = rdma_copy_addr(dev_addr, dev, NULL);
 156                                 break;
 157                         }
 158                 }
 159                 rcu_read_unlock();
 160                 break;
 161 #endif
 162         }
 163         return ret;
 164 }
 165 EXPORT_SYMBOL(rdma_translate_ip);
 166
 167 static void set_timeout(unsigned long time)
 168 {
 169         unsigned long delay;
 170
 171         delay = time - jiffies;
 172         if ((long)delay <= 0)
 173                 delay = 1;
 174
 175         mod_delayed_work(addr_wq, &work, delay);
 176 }
 177
 178 static void queue_req(struct addr_req *req)
 179 {
 180         struct addr_req *temp_req;
 181
 182         mutex_lock(&lock);
 183         list_for_each_entry_reverse(temp_req, &req_list, list) {
 184                 if (time_after_eq(req->timeout, temp_req->timeout))
 185                         break;
 186         }
 187
 188         list_add(&req->list, &temp_req->list);
 189
 190         if (req_list.next == &req->list)
 191                 set_timeout(req->timeout);
 192         mutex_unlock(&lock);
 193 }
 194
 195 static int dst_fetch_ha(struct dst_entry *dst, struct rdma_dev_addr *dev_addr, void *daddr)
 196 {
 197         struct neighbour *n;
 198         int ret;
 199
 200         n = dst_neigh_lookup(dst, daddr);
 201
 202         rcu_read_lock();
 203         if (!n || !(n->nud_state & NUD_VALID)) {
 204                 if (n)
 205                         neigh_event_send(n, NULL);
 206                 ret = -ENODATA;
 207         } else {
 208                 ret = rdma_copy_addr(dev_addr, dst->dev, n->ha);
 209         }
 210         rcu_read_unlock();
 211
 212         if (n)
 213                 neigh_release(n);
 214
 215         return ret;
 216 }
 217
 218 static int addr4_resolve(struct sockaddr_in *src_in,
 219                          struct sockaddr_in *dst_in,
 220                          struct rdma_dev_addr *addr)
 221 {
 222         __be32 src_ip = src_in->sin_addr.s_addr;
 223         __be32 dst_ip = dst_in->sin_addr.s_addr;
 224         struct rtable *rt;
 225         struct flowi4 fl4;
 226         int ret;
 227
 228         memset(&fl4, 0, sizeof(fl4));
 229         fl4.daddr = dst_ip;
 230         fl4.saddr = src_ip;
 231         fl4.flowi4_oif = addr->bound_dev_if;
 232         rt = ip_route_output_key(&init_net, &fl4);
 233         if (IS_ERR(rt)) {
 234                 ret = PTR_ERR(rt);
 235                 goto out;
 236         }
 237         src_in->sin_family = AF_INET;
 238         src_in->sin_addr.s_addr = fl4.saddr;
 239
 240         if (rt->dst.dev->flags & IFF_LOOPBACK) {
 241                 ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
 242                 if (!ret)
 243                         memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
 244                 goto put;
 245         }
 246
 247         /* If the device does ARP internally, return 'done' */
 248         if (rt->dst.dev->flags & IFF_NOARP) {
 249                 ret = rdma_copy_addr(addr, rt->dst.dev, NULL);
 250                 goto put;
 251         }
 252
 253         ret = dst_fetch_ha(&rt->dst, addr, &fl4.daddr);
 254 put:
 255         ip_rt_put(rt);
 256 out:
 257         return ret;
 258 }
 259
 260 #if IS_ENABLED(CONFIG_IPV6)
 261 static int addr6_resolve(struct sockaddr_in6 *src_in,
 262                          struct sockaddr_in6 *dst_in,
 263                          struct rdma_dev_addr *addr)
 264 {
 265         struct flowi6 fl6;
 266         struct dst_entry *dst;
 267         int ret;
 268
 269         memset(&fl6, 0, sizeof fl6);
 270         fl6.daddr = dst_in->sin6_addr;
 271         fl6.saddr = src_in->sin6_addr;
 272         fl6.flowi6_oif = addr->bound_dev_if;
 273
 274         dst = ip6_route_output(&init_net, NULL, &fl6);
 275         if ((ret = dst->error))
 276                 goto put;
 277
 278         if (ipv6_addr_any(&fl6.saddr)) {
 279                 ret = ipv6_dev_get_saddr(&init_net, ip6_dst_idev(dst)->dev,
 280                                          &fl6.daddr, 0, &fl6.saddr);
 281                 if (ret)
 282                         goto put;
 283
 284                 src_in->sin6_family = AF_INET6;
 285                 src_in->sin6_addr = fl6.saddr;
 286         }
 287
 288         if (dst->dev->flags & IFF_LOOPBACK) {
 289                 ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
 290                 if (!ret)
 291                         memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
 292                 goto put;
 293         }
 294
 295         /* If the device does ARP internally, return 'done' */
 296         if (dst->dev->flags & IFF_NOARP) {
 297                 ret = rdma_copy_addr(addr, dst->dev, NULL);
 298                 goto put;
 299         }
 300
 301         ret = dst_fetch_ha(dst, addr, &fl6.daddr);
 302 put:
 303         dst_release(dst);
 304         return ret;
 305 }
 306 #else
 307 static int addr6_resolve(struct sockaddr_in6 *src_in,
 308                          struct sockaddr_in6 *dst_in,
 309                          struct rdma_dev_addr *addr)
 310 {
 311         return -EADDRNOTAVAIL;
 312 }
 313 #endif
 314
 315 static int addr_resolve(struct sockaddr *src_in,
 316                         struct sockaddr *dst_in,
 317                         struct rdma_dev_addr *addr)
 318 {
 319         if (src_in->sa_family == AF_INET) {
 320                 return addr4_resolve((struct sockaddr_in *) src_in,
 321                         (struct sockaddr_in *) dst_in, addr);
 322         } else
 323                 return addr6_resolve((struct sockaddr_in6 *) src_in,
 324                         (struct sockaddr_in6 *) dst_in, addr);
 325 }
 326
 327 static void process_req(struct work_struct *work)
 328 {
 329         struct addr_req *req, *temp_req;
 330         struct sockaddr *src_in, *dst_in;
 331         struct list_head done_list;
 332
 333         INIT_LIST_HEAD(&done_list);
 334
 335         mutex_lock(&lock);
 336         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 337                 if (req->status == -ENODATA) {
 338                         src_in = (struct sockaddr *) &req->src_addr;
 339                         dst_in = (struct sockaddr *) &req->dst_addr;
 340                         req->status = addr_resolve(src_in, dst_in, req->addr);
 341                         if (req->status && time_after_eq(jiffies, req->timeout))
 342                                 req->status = -ETIMEDOUT;
 343                         else if (req->status == -ENODATA)
 344                                 continue;
 345                 }
 346                 list_move_tail(&req->list, &done_list);
 347         }
 348
 349         if (!list_empty(&req_list)) {
 350                 req = list_entry(req_list.next, struct addr_req, list);
 351                 set_timeout(req->timeout);
 352         }
 353         mutex_unlock(&lock);
 354
 355         list_for_each_entry_safe(req, temp_req, &done_list, list) {
 356                 list_del(&req->list);
 357                 req->callback(req->status, (struct sockaddr *) &req->src_addr,
 358                         req->addr, req->context);
 359                 put_client(req->client);
 360                 kfree(req);
 361         }
 362 }
 363
 364 int rdma_resolve_ip(struct rdma_addr_client *client,
 365                     struct sockaddr *src_addr, struct sockaddr *dst_addr,
 366                     struct rdma_dev_addr *addr, int timeout_ms,
 367                     void (*callback)(int status, struct sockaddr *src_addr,
 368                                      struct rdma_dev_addr *addr, void *context),
 369                     void *context)
 370 {
 371         struct sockaddr *src_in, *dst_in;
 372         struct addr_req *req;
 373         int ret = 0;
 374
 375         req = kzalloc(sizeof *req, GFP_KERNEL);
 376         if (!req)
 377                 return -ENOMEM;
 378
 379         src_in = (struct sockaddr *) &req->src_addr;
 380         dst_in = (struct sockaddr *) &req->dst_addr;
 381
 382         if (src_addr) {
 383                 if (src_addr->sa_family != dst_addr->sa_family) {
 384                         ret = -EINVAL;
 385                         goto err;
 386                 }
 387
 388                 memcpy(src_in, src_addr, rdma_addr_size(src_addr));
 389         } else {
 390                 src_in->sa_family = dst_addr->sa_family;
 391         }
 392
 393         memcpy(dst_in, dst_addr, rdma_addr_size(dst_addr));
 394         req->addr = addr;
 395         req->callback = callback;
 396         req->context = context;
 397         req->client = client;
 398         atomic_inc(&client->refcount);
 399
 400         req->status = addr_resolve(src_in, dst_in, addr);
 401         switch (req->status) {
 402         case 0:
 403                 req->timeout = jiffies;
 404                 queue_req(req);
 405                 break;
 406         case -ENODATA:
 407                 req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
 408                 queue_req(req);
 409                 break;
 410         default:
 411                 ret = req->status;
 412                 atomic_dec(&client->refcount);
 413                 goto err;
 414         }
 415         return ret;
 416 err:
 417         kfree(req);
 418         return ret;
 419 }
 420 EXPORT_SYMBOL(rdma_resolve_ip);
 421
 422 void rdma_addr_cancel(struct rdma_dev_addr *addr)
 423 {
 424         struct addr_req *req, *temp_req;
 425
 426         mutex_lock(&lock);
 427         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 428                 if (req->addr == addr) {
 429                         req->status = -ECANCELED;
 430                         req->timeout = jiffies;
 431                         list_move(&req->list, &req_list);
 432                         set_timeout(req->timeout);
 433                         break;
 434                 }
 435         }
 436         mutex_unlock(&lock);
 437 }
 438 EXPORT_SYMBOL(rdma_addr_cancel);
 439
 440 static int netevent_callback(struct notifier_block *self, unsigned long event,
 441         void *ctx)
 442 {
 443         if (event == NETEVENT_NEIGH_UPDATE) {
 444                 struct neighbour *neigh = ctx;
 445
 446                 if (neigh->nud_state & NUD_VALID) {
 447                         set_timeout(jiffies);
 448                 }
 449         }
 450         return 0;
 451 }
 452
 453 static struct notifier_block nb = {
 454         .notifier_call = netevent_callback
 455 };
 456
 457 static int __init addr_init(void)
 458 {
 459         addr_wq = create_singlethread_workqueue("ib_addr");
 460         if (!addr_wq)
 461                 return -ENOMEM;
 462
 463         register_netevent_notifier(&nb);
 464         return 0;
 465 }
 466
 467 static void __exit addr_cleanup(void)
 468 {
 469         unregister_netevent_notifier(&nb);
 470         destroy_workqueue(addr_wq);
 471 }
 472
 473 module_init(addr_init);
 474 module_exit(addr_cleanup);