net/smc/smc_pnet.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   4  *
   5  *  Generic netlink support functions to configure an SMC-R PNET table
   6  *
   7  *  Copyright IBM Corp. 2016
   8  *
   9  *  Author(s):  Thomas Richter <tmricht@linux.vnet.ibm.com>
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/list.h>
  14 #include <linux/ctype.h>
  15 #include <net/netlink.h>
  16 #include <net/genetlink.h>
  17
  18 #include <uapi/linux/if.h>
  19 #include <uapi/linux/smc.h>
  20
  21 #include <rdma/ib_verbs.h>
  22
  23 #include "smc_pnet.h"
  24 #include "smc_ib.h"
  25 #include "smc_ism.h"
  26
  27 static struct nla_policy smc_pnet_policy[SMC_PNETID_MAX + 1] = {
  28         [SMC_PNETID_NAME] = {
  29                 .type = NLA_NUL_STRING,
  30                 .len = SMC_MAX_PNETID_LEN - 1
  31         },
  32         [SMC_PNETID_ETHNAME] = {
  33                 .type = NLA_NUL_STRING,
  34                 .len = IFNAMSIZ - 1
  35         },
  36         [SMC_PNETID_IBNAME] = {
  37                 .type = NLA_NUL_STRING,
  38                 .len = IB_DEVICE_NAME_MAX - 1
  39         },
  40         [SMC_PNETID_IBPORT] = { .type = NLA_U8 }
  41 };
  42
  43 static struct genl_family smc_pnet_nl_family;
  44
  45 /**
  46  * struct smc_pnettable - SMC PNET table anchor
  47  * @lock: Lock for list action
  48  * @pnetlist: List of PNETIDs
  49  */
  50 static struct smc_pnettable {
  51         rwlock_t lock;
  52         struct list_head pnetlist;
  53 } smc_pnettable = {
  54         .pnetlist = LIST_HEAD_INIT(smc_pnettable.pnetlist),
  55         .lock = __RW_LOCK_UNLOCKED(smc_pnettable.lock)
  56 };
  57
  58 /**
  59  * struct smc_pnetentry - pnet identifier name entry
  60  * @list: List node.
  61  * @pnet_name: Pnet identifier name
  62  * @ndev: pointer to network device.
  63  * @smcibdev: Pointer to IB device.
  64  */
  65 struct smc_pnetentry {
  66         struct list_head list;
  67         char pnet_name[SMC_MAX_PNETID_LEN + 1];
  68         struct net_device *ndev;
  69         struct smc_ib_device *smcibdev;
  70         u8 ib_port;
  71 };
  72
  73 /* Check if two RDMA device entries are identical. Use device name and port
  74  * number for comparison.
  75  */
  76 static bool smc_pnet_same_ibname(struct smc_pnetentry *pnetelem, char *ibname,
  77                                  u8 ibport)
  78 {
  79         return pnetelem->ib_port == ibport &&
  80                !strncmp(pnetelem->smcibdev->ibdev->name, ibname,
  81                         sizeof(pnetelem->smcibdev->ibdev->name));
  82 }
  83
  84 /* Find a pnetid in the pnet table.
  85  */
  86 static struct smc_pnetentry *smc_pnet_find_pnetid(char *pnet_name)
  87 {
  88         struct smc_pnetentry *pnetelem, *found_pnetelem = NULL;
  89
  90         read_lock(&smc_pnettable.lock);
  91         list_for_each_entry(pnetelem, &smc_pnettable.pnetlist, list) {
  92                 if (!strncmp(pnetelem->pnet_name, pnet_name,
  93                              sizeof(pnetelem->pnet_name))) {
  94                         found_pnetelem = pnetelem;
  95                         break;
  96                 }
  97         }
  98         read_unlock(&smc_pnettable.lock);
  99         return found_pnetelem;
 100 }
 101
 102 /* Remove a pnetid from the pnet table.
 103  */
 104 static int smc_pnet_remove_by_pnetid(char *pnet_name)
 105 {
 106         struct smc_pnetentry *pnetelem, *tmp_pe;
 107         int rc = -ENOENT;
 108
 109         write_lock(&smc_pnettable.lock);
 110         list_for_each_entry_safe(pnetelem, tmp_pe, &smc_pnettable.pnetlist,
 111                                  list) {
 112                 if (!strncmp(pnetelem->pnet_name, pnet_name,
 113                              sizeof(pnetelem->pnet_name))) {
 114                         list_del(&pnetelem->list);
 115                         dev_put(pnetelem->ndev);
 116                         kfree(pnetelem);
 117                         rc = 0;
 118                         break;
 119                 }
 120         }
 121         write_unlock(&smc_pnettable.lock);
 122         return rc;
 123 }
 124
 125 /* Remove a pnet entry mentioning a given network device from the pnet table.
 126  */
 127 static int smc_pnet_remove_by_ndev(struct net_device *ndev)
 128 {
 129         struct smc_pnetentry *pnetelem, *tmp_pe;
 130         int rc = -ENOENT;
 131
 132         write_lock(&smc_pnettable.lock);
 133         list_for_each_entry_safe(pnetelem, tmp_pe, &smc_pnettable.pnetlist,
 134                                  list) {
 135                 if (pnetelem->ndev == ndev) {
 136                         list_del(&pnetelem->list);
 137                         dev_put(pnetelem->ndev);
 138                         kfree(pnetelem);
 139                         rc = 0;
 140                         break;
 141                 }
 142         }
 143         write_unlock(&smc_pnettable.lock);
 144         return rc;
 145 }
 146
 147 /* Remove a pnet entry mentioning a given ib device from the pnet table.
 148  */
 149 int smc_pnet_remove_by_ibdev(struct smc_ib_device *ibdev)
 150 {
 151         struct smc_pnetentry *pnetelem, *tmp_pe;
 152         int rc = -ENOENT;
 153
 154         write_lock(&smc_pnettable.lock);
 155         list_for_each_entry_safe(pnetelem, tmp_pe, &smc_pnettable.pnetlist,
 156                                  list) {
 157                 if (pnetelem->smcibdev == ibdev) {
 158                         list_del(&pnetelem->list);
 159                         dev_put(pnetelem->ndev);
 160                         kfree(pnetelem);
 161                         rc = 0;
 162                         break;
 163                 }
 164         }
 165         write_unlock(&smc_pnettable.lock);
 166         return rc;
 167 }
 168
 169 /* Append a pnetid to the end of the pnet table if not already on this list.
 170  */
 171 static int smc_pnet_enter(struct smc_pnetentry *new_pnetelem)
 172 {
 173         struct smc_pnetentry *pnetelem;
 174         int rc = -EEXIST;
 175
 176         write_lock(&smc_pnettable.lock);
 177         list_for_each_entry(pnetelem, &smc_pnettable.pnetlist, list) {
 178                 if (!strncmp(pnetelem->pnet_name, new_pnetelem->pnet_name,
 179                              sizeof(new_pnetelem->pnet_name)) ||
 180                     !strncmp(pnetelem->ndev->name, new_pnetelem->ndev->name,
 181                              sizeof(new_pnetelem->ndev->name)) ||
 182                     smc_pnet_same_ibname(pnetelem,
 183                                          new_pnetelem->smcibdev->ibdev->name,
 184                                          new_pnetelem->ib_port)) {
 185                         dev_put(pnetelem->ndev);
 186                         goto found;
 187                 }
 188         }
 189         list_add_tail(&new_pnetelem->list, &smc_pnettable.pnetlist);
 190         rc = 0;
 191 found:
 192         write_unlock(&smc_pnettable.lock);
 193         return rc;
 194 }
 195
 196 /* The limit for pnetid is 16 characters.
 197  * Valid characters should be (single-byte character set) a-z, A-Z, 0-9.
 198  * Lower case letters are converted to upper case.
 199  * Interior blanks should not be used.
 200  */
 201 static bool smc_pnetid_valid(const char *pnet_name, char *pnetid)
 202 {
 203         char *bf = skip_spaces(pnet_name);
 204         size_t len = strlen(bf);
 205         char *end = bf + len;
 206
 207         if (!len)
 208                 return false;
 209         while (--end >= bf && isspace(*end))
 210                 ;
 211         if (end - bf >= SMC_MAX_PNETID_LEN)
 212                 return false;
 213         while (bf <= end) {
 214                 if (!isalnum(*bf))
 215                         return false;
 216                 *pnetid++ = islower(*bf) ? toupper(*bf) : *bf;
 217                 bf++;
 218         }
 219         *pnetid = '\0';
 220         return true;
 221 }
 222
 223 /* Find an infiniband device by a given name. The device might not exist. */
 224 static struct smc_ib_device *smc_pnet_find_ib(char *ib_name)
 225 {
 226         struct smc_ib_device *ibdev;
 227
 228         spin_lock(&smc_ib_devices.lock);
 229         list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
 230                 if (!strncmp(ibdev->ibdev->name, ib_name,
 231                              sizeof(ibdev->ibdev->name))) {
 232                         goto out;
 233                 }
 234         }
 235         ibdev = NULL;
 236 out:
 237         spin_unlock(&smc_ib_devices.lock);
 238         return ibdev;
 239 }
 240
 241 /* Parse the supplied netlink attributes and fill a pnetentry structure.
 242  * For ethernet and infiniband device names verify that the devices exist.
 243  */
 244 static int smc_pnet_fill_entry(struct net *net, struct smc_pnetentry *pnetelem,
 245                                struct nlattr *tb[])
 246 {
 247         char *string, *ibname;
 248         int rc;
 249
 250         memset(pnetelem, 0, sizeof(*pnetelem));
 251         INIT_LIST_HEAD(&pnetelem->list);
 252
 253         rc = -EINVAL;
 254         if (!tb[SMC_PNETID_NAME])
 255                 goto error;
 256         string = (char *)nla_data(tb[SMC_PNETID_NAME]);
 257         if (!smc_pnetid_valid(string, pnetelem->pnet_name))
 258                 goto error;
 259
 260         rc = -EINVAL;
 261         if (!tb[SMC_PNETID_ETHNAME])
 262                 goto error;
 263         rc = -ENOENT;
 264         string = (char *)nla_data(tb[SMC_PNETID_ETHNAME]);
 265         pnetelem->ndev = dev_get_by_name(net, string);
 266         if (!pnetelem->ndev)
 267                 goto error;
 268
 269         rc = -EINVAL;
 270         if (!tb[SMC_PNETID_IBNAME])
 271                 goto error;
 272         rc = -ENOENT;
 273         ibname = (char *)nla_data(tb[SMC_PNETID_IBNAME]);
 274         ibname = strim(ibname);
 275         pnetelem->smcibdev = smc_pnet_find_ib(ibname);
 276         if (!pnetelem->smcibdev)
 277                 goto error;
 278
 279         rc = -EINVAL;
 280         if (!tb[SMC_PNETID_IBPORT])
 281                 goto error;
 282         pnetelem->ib_port = nla_get_u8(tb[SMC_PNETID_IBPORT]);
 283         if (pnetelem->ib_port < 1 || pnetelem->ib_port > SMC_MAX_PORTS)
 284                 goto error;
 285
 286         return 0;
 287
 288 error:
 289         if (pnetelem->ndev)
 290                 dev_put(pnetelem->ndev);
 291         return rc;
 292 }
 293
 294 /* Convert an smc_pnetentry to a netlink attribute sequence */
 295 static int smc_pnet_set_nla(struct sk_buff *msg, struct smc_pnetentry *pnetelem)
 296 {
 297         if (nla_put_string(msg, SMC_PNETID_NAME, pnetelem->pnet_name) ||
 298             nla_put_string(msg, SMC_PNETID_ETHNAME, pnetelem->ndev->name) ||
 299             nla_put_string(msg, SMC_PNETID_IBNAME,
 300                            pnetelem->smcibdev->ibdev->name) ||
 301             nla_put_u8(msg, SMC_PNETID_IBPORT, pnetelem->ib_port))
 302                 return -1;
 303         return 0;
 304 }
 305
 306 /* Retrieve one PNETID entry */
 307 static int smc_pnet_get(struct sk_buff *skb, struct genl_info *info)
 308 {
 309         struct smc_pnetentry *pnetelem;
 310         struct sk_buff *msg;
 311         void *hdr;
 312         int rc;
 313
 314         if (!info->attrs[SMC_PNETID_NAME])
 315                 return -EINVAL;
 316         pnetelem = smc_pnet_find_pnetid(
 317                                 (char *)nla_data(info->attrs[SMC_PNETID_NAME]));
 318         if (!pnetelem)
 319                 return -ENOENT;
 320         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 321         if (!msg)
 322                 return -ENOMEM;
 323
 324         hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
 325                           &smc_pnet_nl_family, 0, SMC_PNETID_GET);
 326         if (!hdr) {
 327                 rc = -EMSGSIZE;
 328                 goto err_out;
 329         }
 330
 331         if (smc_pnet_set_nla(msg, pnetelem)) {
 332                 rc = -ENOBUFS;
 333                 goto err_out;
 334         }
 335
 336         genlmsg_end(msg, hdr);
 337         return genlmsg_reply(msg, info);
 338
 339 err_out:
 340         nlmsg_free(msg);
 341         return rc;
 342 }
 343
 344 static int smc_pnet_add(struct sk_buff *skb, struct genl_info *info)
 345 {
 346         struct net *net = genl_info_net(info);
 347         struct smc_pnetentry *pnetelem;
 348         int rc;
 349
 350         pnetelem = kzalloc(sizeof(*pnetelem), GFP_KERNEL);
 351         if (!pnetelem)
 352                 return -ENOMEM;
 353         rc = smc_pnet_fill_entry(net, pnetelem, info->attrs);
 354         if (!rc)
 355                 rc = smc_pnet_enter(pnetelem);
 356         if (rc) {
 357                 kfree(pnetelem);
 358                 return rc;
 359         }
 360         return rc;
 361 }
 362
 363 static int smc_pnet_del(struct sk_buff *skb, struct genl_info *info)
 364 {
 365         if (!info->attrs[SMC_PNETID_NAME])
 366                 return -EINVAL;
 367         return smc_pnet_remove_by_pnetid(
 368                                 (char *)nla_data(info->attrs[SMC_PNETID_NAME]));
 369 }
 370
 371 static int smc_pnet_dump_start(struct netlink_callback *cb)
 372 {
 373         cb->args[0] = 0;
 374         return 0;
 375 }
 376
 377 static int smc_pnet_dumpinfo(struct sk_buff *skb,
 378                              u32 portid, u32 seq, u32 flags,
 379                              struct smc_pnetentry *pnetelem)
 380 {
 381         void *hdr;
 382
 383         hdr = genlmsg_put(skb, portid, seq, &smc_pnet_nl_family,
 384                           flags, SMC_PNETID_GET);
 385         if (!hdr)
 386                 return -ENOMEM;
 387         if (smc_pnet_set_nla(skb, pnetelem) < 0) {
 388                 genlmsg_cancel(skb, hdr);
 389                 return -EMSGSIZE;
 390         }
 391         genlmsg_end(skb, hdr);
 392         return 0;
 393 }
 394
 395 static int smc_pnet_dump(struct sk_buff *skb, struct netlink_callback *cb)
 396 {
 397         struct smc_pnetentry *pnetelem;
 398         int idx = 0;
 399
 400         read_lock(&smc_pnettable.lock);
 401         list_for_each_entry(pnetelem, &smc_pnettable.pnetlist, list) {
 402                 if (idx++ < cb->args[0])
 403                         continue;
 404                 if (smc_pnet_dumpinfo(skb, NETLINK_CB(cb->skb).portid,
 405                                       cb->nlh->nlmsg_seq, NLM_F_MULTI,
 406                                       pnetelem)) {
 407                         --idx;
 408                         break;
 409                 }
 410         }
 411         cb->args[0] = idx;
 412         read_unlock(&smc_pnettable.lock);
 413         return skb->len;
 414 }
 415
 416 /* Remove and delete all pnetids from pnet table.
 417  */
 418 static int smc_pnet_flush(struct sk_buff *skb, struct genl_info *info)
 419 {
 420         struct smc_pnetentry *pnetelem, *tmp_pe;
 421
 422         write_lock(&smc_pnettable.lock);
 423         list_for_each_entry_safe(pnetelem, tmp_pe, &smc_pnettable.pnetlist,
 424                                  list) {
 425                 list_del(&pnetelem->list);
 426                 dev_put(pnetelem->ndev);
 427                 kfree(pnetelem);
 428         }
 429         write_unlock(&smc_pnettable.lock);
 430         return 0;
 431 }
 432
 433 /* SMC_PNETID generic netlink operation definition */
 434 static const struct genl_ops smc_pnet_ops[] = {
 435         {
 436                 .cmd = SMC_PNETID_GET,
 437                 .flags = GENL_ADMIN_PERM,
 438                 .policy = smc_pnet_policy,
 439                 .doit = smc_pnet_get,
 440                 .dumpit = smc_pnet_dump,
 441                 .start = smc_pnet_dump_start
 442         },
 443         {
 444                 .cmd = SMC_PNETID_ADD,
 445                 .flags = GENL_ADMIN_PERM,
 446                 .policy = smc_pnet_policy,
 447                 .doit = smc_pnet_add
 448         },
 449         {
 450                 .cmd = SMC_PNETID_DEL,
 451                 .flags = GENL_ADMIN_PERM,
 452                 .policy = smc_pnet_policy,
 453                 .doit = smc_pnet_del
 454         },
 455         {
 456                 .cmd = SMC_PNETID_FLUSH,
 457                 .flags = GENL_ADMIN_PERM,
 458                 .policy = smc_pnet_policy,
 459                 .doit = smc_pnet_flush
 460         }
 461 };
 462
 463 /* SMC_PNETID family definition */
 464 static struct genl_family smc_pnet_nl_family __ro_after_init = {
 465         .hdrsize = 0,
 466         .name = SMCR_GENL_FAMILY_NAME,
 467         .version = SMCR_GENL_FAMILY_VERSION,
 468         .maxattr = SMC_PNETID_MAX,
 469         .netnsok = true,
 470         .module = THIS_MODULE,
 471         .ops = smc_pnet_ops,
 472         .n_ops =  ARRAY_SIZE(smc_pnet_ops)
 473 };
 474
 475 static int smc_pnet_netdev_event(struct notifier_block *this,
 476                                  unsigned long event, void *ptr)
 477 {
 478         struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
 479
 480         switch (event) {
 481         case NETDEV_REBOOT:
 482         case NETDEV_UNREGISTER:
 483                 smc_pnet_remove_by_ndev(event_dev);
 484                 return NOTIFY_OK;
 485         default:
 486                 return NOTIFY_DONE;
 487         }
 488 }
 489
 490 static struct notifier_block smc_netdev_notifier = {
 491         .notifier_call = smc_pnet_netdev_event
 492 };
 493
 494 int __init smc_pnet_init(void)
 495 {
 496         int rc;
 497
 498         rc = genl_register_family(&smc_pnet_nl_family);
 499         if (rc)
 500                 return rc;
 501         rc = register_netdevice_notifier(&smc_netdev_notifier);
 502         if (rc)
 503                 genl_unregister_family(&smc_pnet_nl_family);
 504         return rc;
 505 }
 506
 507 void smc_pnet_exit(void)
 508 {
 509         smc_pnet_flush(NULL, NULL);
 510         unregister_netdevice_notifier(&smc_netdev_notifier);
 511         genl_unregister_family(&smc_pnet_nl_family);
 512 }
 513
 514 /* Determine one base device for stacked net devices.
 515  * If the lower device level contains more than one devices
 516  * (for instance with bonding slaves), just the first device
 517  * is used to reach a base device.
 518  */
 519 static struct net_device *pnet_find_base_ndev(struct net_device *ndev)
 520 {
 521         int i, nest_lvl;
 522
 523         rtnl_lock();
 524         nest_lvl = dev_get_nest_level(ndev);
 525         for (i = 0; i < nest_lvl; i++) {
 526                 struct list_head *lower = &ndev->adj_list.lower;
 527
 528                 if (list_empty(lower))
 529                         break;
 530                 lower = lower->next;
 531                 ndev = netdev_lower_get_next(ndev, &lower);
 532         }
 533         rtnl_unlock();
 534         return ndev;
 535 }
 536
 537 /* Determine the corresponding IB device port based on the hardware PNETID.
 538  * Searching stops at the first matching active IB device port with vlan_id
 539  * configured.
 540  */
 541 static void smc_pnet_find_roce_by_pnetid(struct net_device *ndev,
 542                                          struct smc_ib_device **smcibdev,
 543                                          u8 *ibport, unsigned short vlan_id,
 544                                          u8 gid[])
 545 {
 546         u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
 547         struct smc_ib_device *ibdev;
 548         int i;
 549
 550         ndev = pnet_find_base_ndev(ndev);
 551         if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
 552                                    ndev_pnetid))
 553                 return; /* pnetid could not be determined */
 554
 555         spin_lock(&smc_ib_devices.lock);
 556         list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
 557                 for (i = 1; i <= SMC_MAX_PORTS; i++) {
 558                         if (!rdma_is_port_valid(ibdev->ibdev, i))
 559                                 continue;
 560                         if (!memcmp(ibdev->pnetid[i - 1], ndev_pnetid,
 561                                     SMC_MAX_PNETID_LEN) &&
 562                             smc_ib_port_active(ibdev, i) &&
 563                             !smc_ib_determine_gid(ibdev, i, vlan_id, gid,
 564                                                   NULL))  {
 565                                 *smcibdev = ibdev;
 566                                 *ibport = i;
 567                                 goto out;
 568                         }
 569                 }
 570         }
 571 out:
 572         spin_unlock(&smc_ib_devices.lock);
 573 }
 574
 575 static void smc_pnet_find_ism_by_pnetid(struct net_device *ndev,
 576                                         struct smcd_dev **smcismdev)
 577 {
 578         u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
 579         struct smcd_dev *ismdev;
 580
 581         ndev = pnet_find_base_ndev(ndev);
 582         if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
 583                                    ndev_pnetid))
 584                 return; /* pnetid could not be determined */
 585
 586         spin_lock(&smcd_dev_list.lock);
 587         list_for_each_entry(ismdev, &smcd_dev_list.list, list) {
 588                 if (!memcmp(ismdev->pnetid, ndev_pnetid, SMC_MAX_PNETID_LEN)) {
 589                         *smcismdev = ismdev;
 590                         break;
 591                 }
 592         }
 593         spin_unlock(&smcd_dev_list.lock);
 594 }
 595
 596 /* Lookup of coupled ib_device via SMC pnet table */
 597 static void smc_pnet_find_roce_by_table(struct net_device *netdev,
 598                                         struct smc_ib_device **smcibdev,
 599                                         u8 *ibport, unsigned short vlan_id,
 600                                         u8 gid[])
 601 {
 602         struct smc_pnetentry *pnetelem;
 603
 604         read_lock(&smc_pnettable.lock);
 605         list_for_each_entry(pnetelem, &smc_pnettable.pnetlist, list) {
 606                 if (netdev == pnetelem->ndev) {
 607                         if (smc_ib_port_active(pnetelem->smcibdev,
 608                                                pnetelem->ib_port) &&
 609                             !smc_ib_determine_gid(pnetelem->smcibdev,
 610                                                   pnetelem->ib_port, vlan_id,
 611                                                   gid, NULL)) {
 612                                 *smcibdev = pnetelem->smcibdev;
 613                                 *ibport = pnetelem->ib_port;
 614                         }
 615                         break;
 616                 }
 617         }
 618         read_unlock(&smc_pnettable.lock);
 619 }
 620
 621 /* PNET table analysis for a given sock:
 622  * determine ib_device and port belonging to used internal TCP socket
 623  * ethernet interface.
 624  */
 625 void smc_pnet_find_roce_resource(struct sock *sk,
 626                                  struct smc_ib_device **smcibdev, u8 *ibport,
 627                                  unsigned short vlan_id, u8 gid[])
 628 {
 629         struct dst_entry *dst = sk_dst_get(sk);
 630
 631         *smcibdev = NULL;
 632         *ibport = 0;
 633
 634         if (!dst)
 635                 goto out;
 636         if (!dst->dev)
 637                 goto out_rel;
 638
 639         /* if possible, lookup via hardware-defined pnetid */
 640         smc_pnet_find_roce_by_pnetid(dst->dev, smcibdev, ibport, vlan_id, gid);
 641         if (*smcibdev)
 642                 goto out_rel;
 643
 644         /* lookup via SMC PNET table */
 645         smc_pnet_find_roce_by_table(dst->dev, smcibdev, ibport, vlan_id, gid);
 646
 647 out_rel:
 648         dst_release(dst);
 649 out:
 650         return;
 651 }
 652
 653 void smc_pnet_find_ism_resource(struct sock *sk, struct smcd_dev **smcismdev)
 654 {
 655         struct dst_entry *dst = sk_dst_get(sk);
 656
 657         *smcismdev = NULL;
 658         if (!dst)
 659                 goto out;
 660         if (!dst->dev)
 661                 goto out_rel;
 662
 663         /* if possible, lookup via hardware-defined pnetid */
 664         smc_pnet_find_ism_by_pnetid(dst->dev, smcismdev);
 665
 666 out_rel:
 667         dst_release(dst);
 668 out:
 669         return;
 670 }