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 licensed under one of the following licenses:
   8  *
   9  * 1) under the terms of the "Common Public License 1.0" a copy of which is
  10  *    available from the Open Source Initiative, see
  11  *    http://www.opensource.org/licenses/cpl.php.
  12  *
  13  * 2) under the terms of the "The BSD License" a copy of which is
  14  *    available from the Open Source Initiative, see
  15  *    http://www.opensource.org/licenses/bsd-license.php.
  16  *
  17  * 3) under the terms of the "GNU General Public License (GPL) Version 2" a
  18  *    copy of which is available from the Open Source Initiative, see
  19  *    http://www.opensource.org/licenses/gpl-license.php.
  20  *
  21  * Licensee has the right to choose one of the above licenses.
  22  *
  23  * Redistributions of source code must retain the above copyright
  24  * notice and one of the license notices.
  25  *
  26  * Redistributions in binary form must reproduce both the above copyright
  27  * notice, one of the license notices in the documentation
  28  * and/or other materials provided with the distribution.
  29  */
  30
  31 #include <linux/mutex.h>
  32 #include <linux/inetdevice.h>
  33 #include <linux/workqueue.h>
  34 #include <linux/if_arp.h>
  35 #include <net/arp.h>
  36 #include <net/neighbour.h>
  37 #include <net/route.h>
  38 #include <net/netevent.h>
  39 #include <rdma/ib_addr.h>
  40
  41 MODULE_AUTHOR("Sean Hefty");
  42 MODULE_DESCRIPTION("IB Address Translation");
  43 MODULE_LICENSE("Dual BSD/GPL");
  44
  45 struct addr_req {
  46         struct list_head list;
  47         struct sockaddr src_addr;
  48         struct sockaddr dst_addr;
  49         struct rdma_dev_addr *addr;
  50         void *context;
  51         void (*callback)(int status, struct sockaddr *src_addr,
  52                          struct rdma_dev_addr *addr, void *context);
  53         unsigned long timeout;
  54         int status;
  55 };
  56
  57 static void process_req(void *data);
  58
  59 static DEFINE_MUTEX(lock);
  60 static LIST_HEAD(req_list);
  61 static DECLARE_WORK(work, process_req, NULL);
  62 static struct workqueue_struct *addr_wq;
  63
  64 int rdma_copy_addr(struct rdma_dev_addr *dev_addr, struct net_device *dev,
  65                      const unsigned char *dst_dev_addr)
  66 {
  67         switch (dev->type) {
  68         case ARPHRD_INFINIBAND:
  69                 dev_addr->dev_type = RDMA_NODE_IB_CA;
  70                 break;
  71         case ARPHRD_ETHER:
  72                 dev_addr->dev_type = RDMA_NODE_RNIC;
  73                 break;
  74         default:
  75                 return -EADDRNOTAVAIL;
  76         }
  77
  78         memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
  79         memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
  80         if (dst_dev_addr)
  81                 memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
  82         return 0;
  83 }
  84 EXPORT_SYMBOL(rdma_copy_addr);
  85
  86 int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
  87 {
  88         struct net_device *dev;
  89         u32 ip = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
  90         int ret;
  91
  92         dev = ip_dev_find(ip);
  93         if (!dev)
  94                 return -EADDRNOTAVAIL;
  95
  96         ret = rdma_copy_addr(dev_addr, dev, NULL);
  97         dev_put(dev);
  98         return ret;
  99 }
 100 EXPORT_SYMBOL(rdma_translate_ip);
 101
 102 static void set_timeout(unsigned long time)
 103 {
 104         unsigned long delay;
 105
 106         cancel_delayed_work(&work);
 107
 108         delay = time - jiffies;
 109         if ((long)delay <= 0)
 110                 delay = 1;
 111
 112         queue_delayed_work(addr_wq, &work, delay);
 113 }
 114
 115 static void queue_req(struct addr_req *req)
 116 {
 117         struct addr_req *temp_req;
 118
 119         mutex_lock(&lock);
 120         list_for_each_entry_reverse(temp_req, &req_list, list) {
 121                 if (time_after(req->timeout, temp_req->timeout))
 122                         break;
 123         }
 124
 125         list_add(&req->list, &temp_req->list);
 126
 127         if (req_list.next == &req->list)
 128                 set_timeout(req->timeout);
 129         mutex_unlock(&lock);
 130 }
 131
 132 static void addr_send_arp(struct sockaddr_in *dst_in)
 133 {
 134         struct rtable *rt;
 135         struct flowi fl;
 136         u32 dst_ip = dst_in->sin_addr.s_addr;
 137
 138         memset(&fl, 0, sizeof fl);
 139         fl.nl_u.ip4_u.daddr = dst_ip;
 140         if (ip_route_output_key(&rt, &fl))
 141                 return;
 142
 143         arp_send(ARPOP_REQUEST, ETH_P_ARP, rt->rt_gateway, rt->idev->dev,
 144                  rt->rt_src, NULL, rt->idev->dev->dev_addr, NULL);
 145         ip_rt_put(rt);
 146 }
 147
 148 static int addr_resolve_remote(struct sockaddr_in *src_in,
 149                                struct sockaddr_in *dst_in,
 150                                struct rdma_dev_addr *addr)
 151 {
 152         u32 src_ip = src_in->sin_addr.s_addr;
 153         u32 dst_ip = dst_in->sin_addr.s_addr;
 154         struct flowi fl;
 155         struct rtable *rt;
 156         struct neighbour *neigh;
 157         int ret;
 158
 159         memset(&fl, 0, sizeof fl);
 160         fl.nl_u.ip4_u.daddr = dst_ip;
 161         fl.nl_u.ip4_u.saddr = src_ip;
 162         ret = ip_route_output_key(&rt, &fl);
 163         if (ret)
 164                 goto out;
 165
 166         /* If the device does ARP internally, return 'done' */
 167         if (rt->idev->dev->flags & IFF_NOARP) {
 168                 rdma_copy_addr(addr, rt->idev->dev, NULL);
 169                 goto put;
 170         }
 171
 172         neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, rt->idev->dev);
 173         if (!neigh) {
 174                 ret = -ENODATA;
 175                 goto put;
 176         }
 177
 178         if (!(neigh->nud_state & NUD_VALID)) {
 179                 ret = -ENODATA;
 180                 goto release;
 181         }
 182
 183         if (!src_ip) {
 184                 src_in->sin_family = dst_in->sin_family;
 185                 src_in->sin_addr.s_addr = rt->rt_src;
 186         }
 187
 188         ret = rdma_copy_addr(addr, neigh->dev, neigh->ha);
 189 release:
 190         neigh_release(neigh);
 191 put:
 192         ip_rt_put(rt);
 193 out:
 194         return ret;
 195 }
 196
 197 static void process_req(void *data)
 198 {
 199         struct addr_req *req, *temp_req;
 200         struct sockaddr_in *src_in, *dst_in;
 201         struct list_head done_list;
 202
 203         INIT_LIST_HEAD(&done_list);
 204
 205         mutex_lock(&lock);
 206         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 207                 if (req->status) {
 208                         src_in = (struct sockaddr_in *) &req->src_addr;
 209                         dst_in = (struct sockaddr_in *) &req->dst_addr;
 210                         req->status = addr_resolve_remote(src_in, dst_in,
 211                                                           req->addr);
 212                 }
 213                 if (req->status && time_after(jiffies, req->timeout))
 214                         req->status = -ETIMEDOUT;
 215                 else if (req->status == -ENODATA)
 216                         continue;
 217
 218                 list_del(&req->list);
 219                 list_add_tail(&req->list, &done_list);
 220         }
 221
 222         if (!list_empty(&req_list)) {
 223                 req = list_entry(req_list.next, struct addr_req, list);
 224                 set_timeout(req->timeout);
 225         }
 226         mutex_unlock(&lock);
 227
 228         list_for_each_entry_safe(req, temp_req, &done_list, list) {
 229                 list_del(&req->list);
 230                 req->callback(req->status, &req->src_addr, req->addr,
 231                               req->context);
 232                 kfree(req);
 233         }
 234 }
 235
 236 static int addr_resolve_local(struct sockaddr_in *src_in,
 237                               struct sockaddr_in *dst_in,
 238                               struct rdma_dev_addr *addr)
 239 {
 240         struct net_device *dev;
 241         u32 src_ip = src_in->sin_addr.s_addr;
 242         u32 dst_ip = dst_in->sin_addr.s_addr;
 243         int ret;
 244
 245         dev = ip_dev_find(dst_ip);
 246         if (!dev)
 247                 return -EADDRNOTAVAIL;
 248
 249         if (ZERONET(src_ip)) {
 250                 src_in->sin_family = dst_in->sin_family;
 251                 src_in->sin_addr.s_addr = dst_ip;
 252                 ret = rdma_copy_addr(addr, dev, dev->dev_addr);
 253         } else if (LOOPBACK(src_ip)) {
 254                 ret = rdma_translate_ip((struct sockaddr *)dst_in, addr);
 255                 if (!ret)
 256                         memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
 257         } else {
 258                 ret = rdma_translate_ip((struct sockaddr *)src_in, addr);
 259                 if (!ret)
 260                         memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
 261         }
 262
 263         dev_put(dev);
 264         return ret;
 265 }
 266
 267 int rdma_resolve_ip(struct sockaddr *src_addr, struct sockaddr *dst_addr,
 268                     struct rdma_dev_addr *addr, int timeout_ms,
 269                     void (*callback)(int status, struct sockaddr *src_addr,
 270                                      struct rdma_dev_addr *addr, void *context),
 271                     void *context)
 272 {
 273         struct sockaddr_in *src_in, *dst_in;
 274         struct addr_req *req;
 275         int ret = 0;
 276
 277         req = kmalloc(sizeof *req, GFP_KERNEL);
 278         if (!req)
 279                 return -ENOMEM;
 280         memset(req, 0, sizeof *req);
 281
 282         if (src_addr)
 283                 memcpy(&req->src_addr, src_addr, ip_addr_size(src_addr));
 284         memcpy(&req->dst_addr, dst_addr, ip_addr_size(dst_addr));
 285         req->addr = addr;
 286         req->callback = callback;
 287         req->context = context;
 288
 289         src_in = (struct sockaddr_in *) &req->src_addr;
 290         dst_in = (struct sockaddr_in *) &req->dst_addr;
 291
 292         req->status = addr_resolve_local(src_in, dst_in, addr);
 293         if (req->status == -EADDRNOTAVAIL)
 294                 req->status = addr_resolve_remote(src_in, dst_in, addr);
 295
 296         switch (req->status) {
 297         case 0:
 298                 req->timeout = jiffies;
 299                 queue_req(req);
 300                 break;
 301         case -ENODATA:
 302                 req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
 303                 queue_req(req);
 304                 addr_send_arp(dst_in);
 305                 break;
 306         default:
 307                 ret = req->status;
 308                 kfree(req);
 309                 break;
 310         }
 311         return ret;
 312 }
 313 EXPORT_SYMBOL(rdma_resolve_ip);
 314
 315 void rdma_addr_cancel(struct rdma_dev_addr *addr)
 316 {
 317         struct addr_req *req, *temp_req;
 318
 319         mutex_lock(&lock);
 320         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 321                 if (req->addr == addr) {
 322                         req->status = -ECANCELED;
 323                         req->timeout = jiffies;
 324                         list_del(&req->list);
 325                         list_add(&req->list, &req_list);
 326                         set_timeout(req->timeout);
 327                         break;
 328                 }
 329         }
 330         mutex_unlock(&lock);
 331 }
 332 EXPORT_SYMBOL(rdma_addr_cancel);
 333
 334 static int netevent_callback(struct notifier_block *self, unsigned long event,
 335         void *ctx)
 336 {
 337         if (event == NETEVENT_NEIGH_UPDATE) {
 338                 struct neighbour *neigh = ctx;
 339
 340                 if (neigh->dev->type == ARPHRD_INFINIBAND &&
 341                     (neigh->nud_state & NUD_VALID)) {
 342                         set_timeout(jiffies);
 343                 }
 344         }
 345         return 0;
 346 }
 347
 348 static struct notifier_block nb = {
 349         .notifier_call = netevent_callback
 350 };
 351
 352 static int addr_init(void)
 353 {
 354         addr_wq = create_singlethread_workqueue("ib_addr_wq");
 355         if (!addr_wq)
 356                 return -ENOMEM;
 357
 358         register_netevent_notifier(&nb);
 359         return 0;
 360 }
 361
 362 static void addr_cleanup(void)
 363 {
 364         unregister_netevent_notifier(&nb);
 365         destroy_workqueue(addr_wq);
 366 }
 367
 368 module_init(addr_init);
 369 module_exit(addr_cleanup);