net/nfc/netlink.c

   1 /*
   2  * Copyright (C) 2011 Instituto Nokia de Tecnologia
   3  *
   4  * Authors:
   5  *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
   6  *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the
  20  * Free Software Foundation, Inc.,
  21  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  22  */
  23
  24 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
  25
  26 #include <net/genetlink.h>
  27 #include <linux/nfc.h>
  28 #include <linux/slab.h>
  29
  30 #include "nfc.h"
  31
  32 static struct genl_multicast_group nfc_genl_event_mcgrp = {
  33         .name = NFC_GENL_MCAST_EVENT_NAME,
  34 };
  35
  36 struct genl_family nfc_genl_family = {
  37         .id = GENL_ID_GENERATE,
  38         .hdrsize = 0,
  39         .name = NFC_GENL_NAME,
  40         .version = NFC_GENL_VERSION,
  41         .maxattr = NFC_ATTR_MAX,
  42 };
  43
  44 static const struct nla_policy nfc_genl_policy[NFC_ATTR_MAX + 1] = {
  45         [NFC_ATTR_DEVICE_INDEX] = { .type = NLA_U32 },
  46         [NFC_ATTR_DEVICE_NAME] = { .type = NLA_STRING,
  47                                 .len = NFC_DEVICE_NAME_MAXSIZE },
  48         [NFC_ATTR_PROTOCOLS] = { .type = NLA_U32 },
  49         [NFC_ATTR_COMM_MODE] = { .type = NLA_U8 },
  50         [NFC_ATTR_RF_MODE] = { .type = NLA_U8 },
  51         [NFC_ATTR_DEVICE_POWERED] = { .type = NLA_U8 },
  52 };
  53
  54 static int nfc_genl_send_target(struct sk_buff *msg, struct nfc_target *target,
  55                                 struct netlink_callback *cb, int flags)
  56 {
  57         void *hdr;
  58
  59         hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
  60                           &nfc_genl_family, flags, NFC_CMD_GET_TARGET);
  61         if (!hdr)
  62                 return -EMSGSIZE;
  63
  64         genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
  65
  66         if (nla_put_u32(msg, NFC_ATTR_TARGET_INDEX, target->idx) ||
  67             nla_put_u32(msg, NFC_ATTR_PROTOCOLS, target->supported_protocols) ||
  68             nla_put_u16(msg, NFC_ATTR_TARGET_SENS_RES, target->sens_res) ||
  69             nla_put_u8(msg, NFC_ATTR_TARGET_SEL_RES, target->sel_res))
  70                 goto nla_put_failure;
  71         if (target->nfcid1_len > 0 &&
  72             nla_put(msg, NFC_ATTR_TARGET_NFCID1, target->nfcid1_len,
  73                     target->nfcid1))
  74                 goto nla_put_failure;
  75         if (target->sensb_res_len > 0 &&
  76             nla_put(msg, NFC_ATTR_TARGET_SENSB_RES, target->sensb_res_len,
  77                     target->sensb_res))
  78                 goto nla_put_failure;
  79         if (target->sensf_res_len > 0 &&
  80             nla_put(msg, NFC_ATTR_TARGET_SENSF_RES, target->sensf_res_len,
  81                     target->sensf_res))
  82                 goto nla_put_failure;
  83
  84         return genlmsg_end(msg, hdr);
  85
  86 nla_put_failure:
  87         genlmsg_cancel(msg, hdr);
  88         return -EMSGSIZE;
  89 }
  90
  91 static struct nfc_dev *__get_device_from_cb(struct netlink_callback *cb)
  92 {
  93         struct nfc_dev *dev;
  94         int rc;
  95         u32 idx;
  96
  97         rc = nlmsg_parse(cb->nlh, GENL_HDRLEN + nfc_genl_family.hdrsize,
  98                          nfc_genl_family.attrbuf,
  99                          nfc_genl_family.maxattr,
 100                          nfc_genl_policy);
 101         if (rc < 0)
 102                 return ERR_PTR(rc);
 103
 104         if (!nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX])
 105                 return ERR_PTR(-EINVAL);
 106
 107         idx = nla_get_u32(nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX]);
 108
 109         dev = nfc_get_device(idx);
 110         if (!dev)
 111                 return ERR_PTR(-ENODEV);
 112
 113         return dev;
 114 }
 115
 116 static int nfc_genl_dump_targets(struct sk_buff *skb,
 117                                  struct netlink_callback *cb)
 118 {
 119         int i = cb->args[0];
 120         struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
 121         int rc;
 122
 123         if (!dev) {
 124                 dev = __get_device_from_cb(cb);
 125                 if (IS_ERR(dev))
 126                         return PTR_ERR(dev);
 127
 128                 cb->args[1] = (long) dev;
 129         }
 130
 131         spin_lock_bh(&dev->targets_lock);
 132
 133         cb->seq = dev->targets_generation;
 134
 135         while (i < dev->n_targets) {
 136                 rc = nfc_genl_send_target(skb, &dev->targets[i], cb,
 137                                           NLM_F_MULTI);
 138                 if (rc < 0)
 139                         break;
 140
 141                 i++;
 142         }
 143
 144         spin_unlock_bh(&dev->targets_lock);
 145
 146         cb->args[0] = i;
 147
 148         return skb->len;
 149 }
 150
 151 static int nfc_genl_dump_targets_done(struct netlink_callback *cb)
 152 {
 153         struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
 154
 155         if (dev)
 156                 nfc_put_device(dev);
 157
 158         return 0;
 159 }
 160
 161 int nfc_genl_targets_found(struct nfc_dev *dev)
 162 {
 163         struct sk_buff *msg;
 164         void *hdr;
 165
 166         dev->genl_data.poll_req_pid = 0;
 167
 168         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
 169         if (!msg)
 170                 return -ENOMEM;
 171
 172         hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
 173                           NFC_EVENT_TARGETS_FOUND);
 174         if (!hdr)
 175                 goto free_msg;
 176
 177         if (nla_put_u32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx))
 178                 goto nla_put_failure;
 179
 180         genlmsg_end(msg, hdr);
 181
 182         return genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);
 183
 184 nla_put_failure:
 185         genlmsg_cancel(msg, hdr);
 186 free_msg:
 187         nlmsg_free(msg);
 188         return -EMSGSIZE;
 189 }
 190
 191 int nfc_genl_device_added(struct nfc_dev *dev)
 192 {
 193         struct sk_buff *msg;
 194         void *hdr;
 195
 196         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
 197         if (!msg)
 198                 return -ENOMEM;
 199
 200         hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
 201                           NFC_EVENT_DEVICE_ADDED);
 202         if (!hdr)
 203                 goto free_msg;
 204
 205         if (nla_put_string(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev)) ||
 206             nla_put_u32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx) ||
 207             nla_put_u32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols) ||
 208             nla_put_u8(msg, NFC_ATTR_DEVICE_POWERED, dev->dev_up))
 209                 goto nla_put_failure;
 210
 211         genlmsg_end(msg, hdr);
 212
 213         genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);
 214
 215         return 0;
 216
 217 nla_put_failure:
 218         genlmsg_cancel(msg, hdr);
 219 free_msg:
 220         nlmsg_free(msg);
 221         return -EMSGSIZE;
 222 }
 223
 224 int nfc_genl_device_removed(struct nfc_dev *dev)
 225 {
 226         struct sk_buff *msg;
 227         void *hdr;
 228
 229         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
 230         if (!msg)
 231                 return -ENOMEM;
 232
 233         hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
 234                           NFC_EVENT_DEVICE_REMOVED);
 235         if (!hdr)
 236                 goto free_msg;
 237
 238         if (nla_put_u32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx))
 239                 goto nla_put_failure;
 240
 241         genlmsg_end(msg, hdr);
 242
 243         genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);
 244
 245         return 0;
 246
 247 nla_put_failure:
 248         genlmsg_cancel(msg, hdr);
 249 free_msg:
 250         nlmsg_free(msg);
 251         return -EMSGSIZE;
 252 }
 253
 254 static int nfc_genl_send_device(struct sk_buff *msg, struct nfc_dev *dev,
 255                                 u32 pid, u32 seq,
 256                                 struct netlink_callback *cb,
 257                                 int flags)
 258 {
 259         void *hdr;
 260
 261         hdr = genlmsg_put(msg, pid, seq, &nfc_genl_family, flags,
 262                           NFC_CMD_GET_DEVICE);
 263         if (!hdr)
 264                 return -EMSGSIZE;
 265
 266         if (cb)
 267                 genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
 268
 269         if (nla_put_string(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev)) ||
 270             nla_put_u32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx) ||
 271             nla_put_u32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols) ||
 272             nla_put_u8(msg, NFC_ATTR_DEVICE_POWERED, dev->dev_up))
 273                 goto nla_put_failure;
 274
 275         return genlmsg_end(msg, hdr);
 276
 277 nla_put_failure:
 278         genlmsg_cancel(msg, hdr);
 279         return -EMSGSIZE;
 280 }
 281
 282 static int nfc_genl_dump_devices(struct sk_buff *skb,
 283                                  struct netlink_callback *cb)
 284 {
 285         struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0];
 286         struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
 287         bool first_call = false;
 288
 289         if (!iter) {
 290                 first_call = true;
 291                 iter = kmalloc(sizeof(struct class_dev_iter), GFP_KERNEL);
 292                 if (!iter)
 293                         return -ENOMEM;
 294                 cb->args[0] = (long) iter;
 295         }
 296
 297         mutex_lock(&nfc_devlist_mutex);
 298
 299         cb->seq = nfc_devlist_generation;
 300
 301         if (first_call) {
 302                 nfc_device_iter_init(iter);
 303                 dev = nfc_device_iter_next(iter);
 304         }
 305
 306         while (dev) {
 307                 int rc;
 308
 309                 rc = nfc_genl_send_device(skb, dev, NETLINK_CB(cb->skb).pid,
 310                                           cb->nlh->nlmsg_seq, cb, NLM_F_MULTI);
 311                 if (rc < 0)
 312                         break;
 313
 314                 dev = nfc_device_iter_next(iter);
 315         }
 316
 317         mutex_unlock(&nfc_devlist_mutex);
 318
 319         cb->args[1] = (long) dev;
 320
 321         return skb->len;
 322 }
 323
 324 static int nfc_genl_dump_devices_done(struct netlink_callback *cb)
 325 {
 326         struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0];
 327
 328         nfc_device_iter_exit(iter);
 329         kfree(iter);
 330
 331         return 0;
 332 }
 333
 334 int nfc_genl_dep_link_up_event(struct nfc_dev *dev, u32 target_idx,
 335                                u8 comm_mode, u8 rf_mode)
 336 {
 337         struct sk_buff *msg;
 338         void *hdr;
 339
 340         pr_debug("DEP link is up\n");
 341
 342         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
 343         if (!msg)
 344                 return -ENOMEM;
 345
 346         hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0, NFC_CMD_DEP_LINK_UP);
 347         if (!hdr)
 348                 goto free_msg;
 349
 350         if (nla_put_u32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx))
 351                 goto nla_put_failure;
 352         if (rf_mode == NFC_RF_INITIATOR &&
 353             nla_put_u32(msg, NFC_ATTR_TARGET_INDEX, target_idx))
 354                 goto nla_put_failure;
 355         if (nla_put_u8(msg, NFC_ATTR_COMM_MODE, comm_mode) ||
 356             nla_put_u8(msg, NFC_ATTR_RF_MODE, rf_mode))
 357                 goto nla_put_failure;
 358
 359         genlmsg_end(msg, hdr);
 360
 361         dev->dep_link_up = true;
 362
 363         genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);
 364
 365         return 0;
 366
 367 nla_put_failure:
 368         genlmsg_cancel(msg, hdr);
 369 free_msg:
 370         nlmsg_free(msg);
 371         return -EMSGSIZE;
 372 }
 373
 374 int nfc_genl_dep_link_down_event(struct nfc_dev *dev)
 375 {
 376         struct sk_buff *msg;
 377         void *hdr;
 378
 379         pr_debug("DEP link is down\n");
 380
 381         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
 382         if (!msg)
 383                 return -ENOMEM;
 384
 385         hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
 386                           NFC_CMD_DEP_LINK_DOWN);
 387         if (!hdr)
 388                 goto free_msg;
 389
 390         if (nla_put_u32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx))
 391                 goto nla_put_failure;
 392
 393         genlmsg_end(msg, hdr);
 394
 395         genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);
 396
 397         return 0;
 398
 399 nla_put_failure:
 400         genlmsg_cancel(msg, hdr);
 401 free_msg:
 402         nlmsg_free(msg);
 403         return -EMSGSIZE;
 404 }
 405
 406 static int nfc_genl_get_device(struct sk_buff *skb, struct genl_info *info)
 407 {
 408         struct sk_buff *msg;
 409         struct nfc_dev *dev;
 410         u32 idx;
 411         int rc = -ENOBUFS;
 412
 413         if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
 414                 return -EINVAL;
 415
 416         idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
 417
 418         dev = nfc_get_device(idx);
 419         if (!dev)
 420                 return -ENODEV;
 421
 422         msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
 423         if (!msg) {
 424                 rc = -ENOMEM;
 425                 goto out_putdev;
 426         }
 427
 428         rc = nfc_genl_send_device(msg, dev, info->snd_pid, info->snd_seq,
 429                                   NULL, 0);
 430         if (rc < 0)
 431                 goto out_free;
 432
 433         nfc_put_device(dev);
 434
 435         return genlmsg_reply(msg, info);
 436
 437 out_free:
 438         nlmsg_free(msg);
 439 out_putdev:
 440         nfc_put_device(dev);
 441         return rc;
 442 }
 443
 444 static int nfc_genl_dev_up(struct sk_buff *skb, struct genl_info *info)
 445 {
 446         struct nfc_dev *dev;
 447         int rc;
 448         u32 idx;
 449
 450         if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
 451                 return -EINVAL;
 452
 453         idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
 454
 455         dev = nfc_get_device(idx);
 456         if (!dev)
 457                 return -ENODEV;
 458
 459         rc = nfc_dev_up(dev);
 460
 461         nfc_put_device(dev);
 462         return rc;
 463 }
 464
 465 static int nfc_genl_dev_down(struct sk_buff *skb, struct genl_info *info)
 466 {
 467         struct nfc_dev *dev;
 468         int rc;
 469         u32 idx;
 470
 471         if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
 472                 return -EINVAL;
 473
 474         idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
 475
 476         dev = nfc_get_device(idx);
 477         if (!dev)
 478                 return -ENODEV;
 479
 480         rc = nfc_dev_down(dev);
 481
 482         nfc_put_device(dev);
 483         return rc;
 484 }
 485
 486 static int nfc_genl_start_poll(struct sk_buff *skb, struct genl_info *info)
 487 {
 488         struct nfc_dev *dev;
 489         int rc;
 490         u32 idx;
 491         u32 protocols;
 492
 493         pr_debug("Poll start\n");
 494
 495         if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
 496             !info->attrs[NFC_ATTR_PROTOCOLS])
 497                 return -EINVAL;
 498
 499         idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
 500         protocols = nla_get_u32(info->attrs[NFC_ATTR_PROTOCOLS]);
 501
 502         dev = nfc_get_device(idx);
 503         if (!dev)
 504                 return -ENODEV;
 505
 506         mutex_lock(&dev->genl_data.genl_data_mutex);
 507
 508         rc = nfc_start_poll(dev, protocols);
 509         if (!rc)
 510                 dev->genl_data.poll_req_pid = info->snd_pid;
 511
 512         mutex_unlock(&dev->genl_data.genl_data_mutex);
 513
 514         nfc_put_device(dev);
 515         return rc;
 516 }
 517
 518 static int nfc_genl_stop_poll(struct sk_buff *skb, struct genl_info *info)
 519 {
 520         struct nfc_dev *dev;
 521         int rc;
 522         u32 idx;
 523
 524         if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
 525                 return -EINVAL;
 526
 527         idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
 528
 529         dev = nfc_get_device(idx);
 530         if (!dev)
 531                 return -ENODEV;
 532
 533         mutex_lock(&dev->genl_data.genl_data_mutex);
 534
 535         if (dev->genl_data.poll_req_pid != info->snd_pid) {
 536                 rc = -EBUSY;
 537                 goto out;
 538         }
 539
 540         rc = nfc_stop_poll(dev);
 541         dev->genl_data.poll_req_pid = 0;
 542
 543 out:
 544         mutex_unlock(&dev->genl_data.genl_data_mutex);
 545         nfc_put_device(dev);
 546         return rc;
 547 }
 548
 549 static int nfc_genl_dep_link_up(struct sk_buff *skb, struct genl_info *info)
 550 {
 551         struct nfc_dev *dev;
 552         int rc, tgt_idx;
 553         u32 idx;
 554         u8 comm;
 555
 556         pr_debug("DEP link up\n");
 557
 558         if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
 559             !info->attrs[NFC_ATTR_COMM_MODE])
 560                 return -EINVAL;
 561
 562         idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
 563         if (!info->attrs[NFC_ATTR_TARGET_INDEX])
 564                 tgt_idx = NFC_TARGET_IDX_ANY;
 565         else
 566                 tgt_idx = nla_get_u32(info->attrs[NFC_ATTR_TARGET_INDEX]);
 567
 568         comm = nla_get_u8(info->attrs[NFC_ATTR_COMM_MODE]);
 569
 570         if (comm != NFC_COMM_ACTIVE && comm != NFC_COMM_PASSIVE)
 571                 return -EINVAL;
 572
 573         dev = nfc_get_device(idx);
 574         if (!dev)
 575                 return -ENODEV;
 576
 577         rc = nfc_dep_link_up(dev, tgt_idx, comm);
 578
 579         nfc_put_device(dev);
 580
 581         return rc;
 582 }
 583
 584 static int nfc_genl_dep_link_down(struct sk_buff *skb, struct genl_info *info)
 585 {
 586         struct nfc_dev *dev;
 587         int rc;
 588         u32 idx;
 589
 590         if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
 591                 return -EINVAL;
 592
 593         idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
 594
 595         dev = nfc_get_device(idx);
 596         if (!dev)
 597                 return -ENODEV;
 598
 599         rc = nfc_dep_link_down(dev);
 600
 601         nfc_put_device(dev);
 602         return rc;
 603 }
 604
 605 static struct genl_ops nfc_genl_ops[] = {
 606         {
 607                 .cmd = NFC_CMD_GET_DEVICE,
 608                 .doit = nfc_genl_get_device,
 609                 .dumpit = nfc_genl_dump_devices,
 610                 .done = nfc_genl_dump_devices_done,
 611                 .policy = nfc_genl_policy,
 612         },
 613         {
 614                 .cmd = NFC_CMD_DEV_UP,
 615                 .doit = nfc_genl_dev_up,
 616                 .policy = nfc_genl_policy,
 617         },
 618         {
 619                 .cmd = NFC_CMD_DEV_DOWN,
 620                 .doit = nfc_genl_dev_down,
 621                 .policy = nfc_genl_policy,
 622         },
 623         {
 624                 .cmd = NFC_CMD_START_POLL,
 625                 .doit = nfc_genl_start_poll,
 626                 .policy = nfc_genl_policy,
 627         },
 628         {
 629                 .cmd = NFC_CMD_STOP_POLL,
 630                 .doit = nfc_genl_stop_poll,
 631                 .policy = nfc_genl_policy,
 632         },
 633         {
 634                 .cmd = NFC_CMD_DEP_LINK_UP,
 635                 .doit = nfc_genl_dep_link_up,
 636                 .policy = nfc_genl_policy,
 637         },
 638         {
 639                 .cmd = NFC_CMD_DEP_LINK_DOWN,
 640                 .doit = nfc_genl_dep_link_down,
 641                 .policy = nfc_genl_policy,
 642         },
 643         {
 644                 .cmd = NFC_CMD_GET_TARGET,
 645                 .dumpit = nfc_genl_dump_targets,
 646                 .done = nfc_genl_dump_targets_done,
 647                 .policy = nfc_genl_policy,
 648         },
 649 };
 650
 651 static int nfc_genl_rcv_nl_event(struct notifier_block *this,
 652                                  unsigned long event, void *ptr)
 653 {
 654         struct netlink_notify *n = ptr;
 655         struct class_dev_iter iter;
 656         struct nfc_dev *dev;
 657
 658         if (event != NETLINK_URELEASE || n->protocol != NETLINK_GENERIC)
 659                 goto out;
 660
 661         pr_debug("NETLINK_URELEASE event from id %d\n", n->pid);
 662
 663         nfc_device_iter_init(&iter);
 664         dev = nfc_device_iter_next(&iter);
 665
 666         while (dev) {
 667                 if (dev->genl_data.poll_req_pid == n->pid) {
 668                         nfc_stop_poll(dev);
 669                         dev->genl_data.poll_req_pid = 0;
 670                 }
 671                 dev = nfc_device_iter_next(&iter);
 672         }
 673
 674         nfc_device_iter_exit(&iter);
 675
 676 out:
 677         return NOTIFY_DONE;
 678 }
 679
 680 void nfc_genl_data_init(struct nfc_genl_data *genl_data)
 681 {
 682         genl_data->poll_req_pid = 0;
 683         mutex_init(&genl_data->genl_data_mutex);
 684 }
 685
 686 void nfc_genl_data_exit(struct nfc_genl_data *genl_data)
 687 {
 688         mutex_destroy(&genl_data->genl_data_mutex);
 689 }
 690
 691 static struct notifier_block nl_notifier = {
 692         .notifier_call  = nfc_genl_rcv_nl_event,
 693 };
 694
 695 /**
 696  * nfc_genl_init() - Initialize netlink interface
 697  *
 698  * This initialization function registers the nfc netlink family.
 699  */
 700 int __init nfc_genl_init(void)
 701 {
 702         int rc;
 703
 704         rc = genl_register_family_with_ops(&nfc_genl_family, nfc_genl_ops,
 705                                            ARRAY_SIZE(nfc_genl_ops));
 706         if (rc)
 707                 return rc;
 708
 709         rc = genl_register_mc_group(&nfc_genl_family, &nfc_genl_event_mcgrp);
 710
 711         netlink_register_notifier(&nl_notifier);
 712
 713         return rc;
 714 }
 715
 716 /**
 717  * nfc_genl_exit() - Deinitialize netlink interface
 718  *
 719  * This exit function unregisters the nfc netlink family.
 720  */
 721 void nfc_genl_exit(void)
 722 {
 723         netlink_unregister_notifier(&nl_notifier);
 724         genl_unregister_family(&nfc_genl_family);
 725 }