drivers/nvme/host/fabrics.c

   1 /*
   2  * NVMe over Fabrics common host code.
   3  * Copyright (c) 2015-2016 HGST, a Western Digital Company.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  */
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15 #include <linux/init.h>
  16 #include <linux/miscdevice.h>
  17 #include <linux/module.h>
  18 #include <linux/mutex.h>
  19 #include <linux/parser.h>
  20 #include <linux/seq_file.h>
  21 #include "nvme.h"
  22 #include "fabrics.h"
  23
  24 static LIST_HEAD(nvmf_transports);
  25 static DEFINE_MUTEX(nvmf_transports_mutex);
  26
  27 static LIST_HEAD(nvmf_hosts);
  28 static DEFINE_MUTEX(nvmf_hosts_mutex);
  29
  30 static struct nvmf_host *nvmf_default_host;
  31
  32 static struct nvmf_host *__nvmf_host_find(const char *hostnqn)
  33 {
  34         struct nvmf_host *host;
  35
  36         list_for_each_entry(host, &nvmf_hosts, list) {
  37                 if (!strcmp(host->nqn, hostnqn))
  38                         return host;
  39         }
  40
  41         return NULL;
  42 }
  43
  44 static struct nvmf_host *nvmf_host_add(const char *hostnqn)
  45 {
  46         struct nvmf_host *host;
  47
  48         mutex_lock(&nvmf_hosts_mutex);
  49         host = __nvmf_host_find(hostnqn);
  50         if (host)
  51                 goto out_unlock;
  52
  53         host = kmalloc(sizeof(*host), GFP_KERNEL);
  54         if (!host)
  55                 goto out_unlock;
  56
  57         kref_init(&host->ref);
  58         memcpy(host->nqn, hostnqn, NVMF_NQN_SIZE);
  59         uuid_le_gen(&host->id);
  60
  61         list_add_tail(&host->list, &nvmf_hosts);
  62 out_unlock:
  63         mutex_unlock(&nvmf_hosts_mutex);
  64         return host;
  65 }
  66
  67 static struct nvmf_host *nvmf_host_default(void)
  68 {
  69         struct nvmf_host *host;
  70
  71         host = kmalloc(sizeof(*host), GFP_KERNEL);
  72         if (!host)
  73                 return NULL;
  74
  75         kref_init(&host->ref);
  76         uuid_le_gen(&host->id);
  77         snprintf(host->nqn, NVMF_NQN_SIZE,
  78                 "nqn.2014-08.org.nvmexpress:NVMf:uuid:%pUl", &host->id);
  79
  80         mutex_lock(&nvmf_hosts_mutex);
  81         list_add_tail(&host->list, &nvmf_hosts);
  82         mutex_unlock(&nvmf_hosts_mutex);
  83
  84         return host;
  85 }
  86
  87 static void nvmf_host_destroy(struct kref *ref)
  88 {
  89         struct nvmf_host *host = container_of(ref, struct nvmf_host, ref);
  90
  91         kfree(host);
  92 }
  93
  94 static void nvmf_host_put(struct nvmf_host *host)
  95 {
  96         if (host)
  97                 kref_put(&host->ref, nvmf_host_destroy);
  98 }
  99
 100 /**
 101  * nvmf_get_address() -  Get address/port
 102  * @ctrl:       Host NVMe controller instance which we got the address
 103  * @buf:        OUTPUT parameter that will contain the address/port
 104  * @size:       buffer size
 105  */
 106 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
 107 {
 108         return snprintf(buf, size, "traddr=%s,trsvcid=%s\n",
 109                         ctrl->opts->traddr, ctrl->opts->trsvcid);
 110 }
 111 EXPORT_SYMBOL_GPL(nvmf_get_address);
 112
 113 /**
 114  * nvmf_get_subsysnqn() - Get subsystem NQN
 115  * @ctrl:       Host NVMe controller instance which we got the NQN
 116  */
 117 const char *nvmf_get_subsysnqn(struct nvme_ctrl *ctrl)
 118 {
 119         return ctrl->opts->subsysnqn;
 120 }
 121 EXPORT_SYMBOL_GPL(nvmf_get_subsysnqn);
 122
 123 /**
 124  * nvmf_reg_read32() -  NVMe Fabrics "Property Get" API function.
 125  * @ctrl:       Host NVMe controller instance maintaining the admin
 126  *              queue used to submit the property read command to
 127  *              the allocated NVMe controller resource on the target system.
 128  * @off:        Starting offset value of the targeted property
 129  *              register (see the fabrics section of the NVMe standard).
 130  * @val:        OUTPUT parameter that will contain the value of
 131  *              the property after a successful read.
 132  *
 133  * Used by the host system to retrieve a 32-bit capsule property value
 134  * from an NVMe controller on the target system.
 135  *
 136  * ("Capsule property" is an "PCIe register concept" applied to the
 137  * NVMe fabrics space.)
 138  *
 139  * Return:
 140  *      0: successful read
 141  *      > 0: NVMe error status code
 142  *      < 0: Linux errno error code
 143  */
 144 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
 145 {
 146         struct nvme_command cmd;
 147         struct nvme_completion cqe;
 148         int ret;
 149
 150         memset(&cmd, 0, sizeof(cmd));
 151         cmd.prop_get.opcode = nvme_fabrics_command;
 152         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
 153         cmd.prop_get.offset = cpu_to_le32(off);
 154
 155         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &cqe, NULL, 0, 0,
 156                         NVME_QID_ANY, 0, 0);
 157
 158         if (ret >= 0)
 159                 *val = le64_to_cpu(cqe.result64);
 160         if (unlikely(ret != 0))
 161                 dev_err(ctrl->device,
 162                         "Property Get error: %d, offset %#x\n",
 163                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 164
 165         return ret;
 166 }
 167 EXPORT_SYMBOL_GPL(nvmf_reg_read32);
 168
 169 /**
 170  * nvmf_reg_read64() -  NVMe Fabrics "Property Get" API function.
 171  * @ctrl:       Host NVMe controller instance maintaining the admin
 172  *              queue used to submit the property read command to
 173  *              the allocated controller resource on the target system.
 174  * @off:        Starting offset value of the targeted property
 175  *              register (see the fabrics section of the NVMe standard).
 176  * @val:        OUTPUT parameter that will contain the value of
 177  *              the property after a successful read.
 178  *
 179  * Used by the host system to retrieve a 64-bit capsule property value
 180  * from an NVMe controller on the target system.
 181  *
 182  * ("Capsule property" is an "PCIe register concept" applied to the
 183  * NVMe fabrics space.)
 184  *
 185  * Return:
 186  *      0: successful read
 187  *      > 0: NVMe error status code
 188  *      < 0: Linux errno error code
 189  */
 190 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
 191 {
 192         struct nvme_command cmd;
 193         struct nvme_completion cqe;
 194         int ret;
 195
 196         memset(&cmd, 0, sizeof(cmd));
 197         cmd.prop_get.opcode = nvme_fabrics_command;
 198         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
 199         cmd.prop_get.attrib = 1;
 200         cmd.prop_get.offset = cpu_to_le32(off);
 201
 202         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &cqe, NULL, 0, 0,
 203                         NVME_QID_ANY, 0, 0);
 204
 205         if (ret >= 0)
 206                 *val = le64_to_cpu(cqe.result64);
 207         if (unlikely(ret != 0))
 208                 dev_err(ctrl->device,
 209                         "Property Get error: %d, offset %#x\n",
 210                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 211         return ret;
 212 }
 213 EXPORT_SYMBOL_GPL(nvmf_reg_read64);
 214
 215 /**
 216  * nvmf_reg_write32() -  NVMe Fabrics "Property Write" API function.
 217  * @ctrl:       Host NVMe controller instance maintaining the admin
 218  *              queue used to submit the property read command to
 219  *              the allocated NVMe controller resource on the target system.
 220  * @off:        Starting offset value of the targeted property
 221  *              register (see the fabrics section of the NVMe standard).
 222  * @val:        Input parameter that contains the value to be
 223  *              written to the property.
 224  *
 225  * Used by the NVMe host system to write a 32-bit capsule property value
 226  * to an NVMe controller on the target system.
 227  *
 228  * ("Capsule property" is an "PCIe register concept" applied to the
 229  * NVMe fabrics space.)
 230  *
 231  * Return:
 232  *      0: successful write
 233  *      > 0: NVMe error status code
 234  *      < 0: Linux errno error code
 235  */
 236 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
 237 {
 238         struct nvme_command cmd;
 239         int ret;
 240
 241         memset(&cmd, 0, sizeof(cmd));
 242         cmd.prop_set.opcode = nvme_fabrics_command;
 243         cmd.prop_set.fctype = nvme_fabrics_type_property_set;
 244         cmd.prop_set.attrib = 0;
 245         cmd.prop_set.offset = cpu_to_le32(off);
 246         cmd.prop_set.value = cpu_to_le64(val);
 247
 248         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, NULL, NULL, 0, 0,
 249                         NVME_QID_ANY, 0, 0);
 250         if (unlikely(ret))
 251                 dev_err(ctrl->device,
 252                         "Property Set error: %d, offset %#x\n",
 253                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 254         return ret;
 255 }
 256 EXPORT_SYMBOL_GPL(nvmf_reg_write32);
 257
 258 /**
 259  * nvmf_log_connect_error() - Error-parsing-diagnostic print
 260  * out function for connect() errors.
 261  *
 262  * @ctrl: the specific /dev/nvmeX device that had the error.
 263  *
 264  * @errval: Error code to be decoded in a more human-friendly
 265  *          printout.
 266  *
 267  * @offset: For use with the NVMe error code NVME_SC_CONNECT_INVALID_PARAM.
 268  *
 269  * @cmd: This is the SQE portion of a submission capsule.
 270  *
 271  * @data: This is the "Data" portion of a submission capsule.
 272  */
 273 static void nvmf_log_connect_error(struct nvme_ctrl *ctrl,
 274                 int errval, int offset, struct nvme_command *cmd,
 275                 struct nvmf_connect_data *data)
 276 {
 277         int err_sctype = errval & (~NVME_SC_DNR);
 278
 279         switch (err_sctype) {
 280
 281         case (NVME_SC_CONNECT_INVALID_PARAM):
 282                 if (offset >> 16) {
 283                         char *inv_data = "Connect Invalid Data Parameter";
 284
 285                         switch (offset & 0xffff) {
 286                         case (offsetof(struct nvmf_connect_data, cntlid)):
 287                                 dev_err(ctrl->device,
 288                                         "%s, cntlid: %d\n",
 289                                         inv_data, data->cntlid);
 290                                 break;
 291                         case (offsetof(struct nvmf_connect_data, hostnqn)):
 292                                 dev_err(ctrl->device,
 293                                         "%s, hostnqn \"%s\"\n",
 294                                         inv_data, data->hostnqn);
 295                                 break;
 296                         case (offsetof(struct nvmf_connect_data, subsysnqn)):
 297                                 dev_err(ctrl->device,
 298                                         "%s, subsysnqn \"%s\"\n",
 299                                         inv_data, data->subsysnqn);
 300                                 break;
 301                         default:
 302                                 dev_err(ctrl->device,
 303                                         "%s, starting byte offset: %d\n",
 304                                        inv_data, offset & 0xffff);
 305                                 break;
 306                         }
 307                 } else {
 308                         char *inv_sqe = "Connect Invalid SQE Parameter";
 309
 310                         switch (offset) {
 311                         case (offsetof(struct nvmf_connect_command, qid)):
 312                                 dev_err(ctrl->device,
 313                                        "%s, qid %d\n",
 314                                         inv_sqe, cmd->connect.qid);
 315                                 break;
 316                         default:
 317                                 dev_err(ctrl->device,
 318                                         "%s, starting byte offset: %d\n",
 319                                         inv_sqe, offset);
 320                         }
 321                 }
 322                 break;
 323         default:
 324                 dev_err(ctrl->device,
 325                         "Connect command failed, error wo/DNR bit: %d\n",
 326                         err_sctype);
 327                 break;
 328         } /* switch (err_sctype) */
 329 }
 330
 331 /**
 332  * nvmf_connect_admin_queue() - NVMe Fabrics Admin Queue "Connect"
 333  *                              API function.
 334  * @ctrl:       Host nvme controller instance used to request
 335  *              a new NVMe controller allocation on the target
 336  *              system and  establish an NVMe Admin connection to
 337  *              that controller.
 338  *
 339  * This function enables an NVMe host device to request a new allocation of
 340  * an NVMe controller resource on a target system as well establish a
 341  * fabrics-protocol connection of the NVMe Admin queue between the
 342  * host system device and the allocated NVMe controller on the
 343  * target system via a NVMe Fabrics "Connect" command.
 344  *
 345  * Return:
 346  *      0: success
 347  *      > 0: NVMe error status code
 348  *      < 0: Linux errno error code
 349  *
 350  */
 351 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
 352 {
 353         struct nvme_command cmd;
 354         struct nvme_completion cqe;
 355         struct nvmf_connect_data *data;
 356         int ret;
 357
 358         memset(&cmd, 0, sizeof(cmd));
 359         cmd.connect.opcode = nvme_fabrics_command;
 360         cmd.connect.fctype = nvme_fabrics_type_connect;
 361         cmd.connect.qid = 0;
 362         cmd.connect.sqsize = cpu_to_le16(ctrl->sqsize);
 363         /*
 364          * Set keep-alive timeout in seconds granularity (ms * 1000)
 365          * and add a grace period for controller kato enforcement
 366          */
 367         cmd.connect.kato = ctrl->opts->discovery_nqn ? 0 :
 368                 cpu_to_le32((ctrl->kato + NVME_KATO_GRACE) * 1000);
 369
 370         data = kzalloc(sizeof(*data), GFP_KERNEL);
 371         if (!data)
 372                 return -ENOMEM;
 373
 374         memcpy(&data->hostid, &ctrl->opts->host->id, sizeof(uuid_le));
 375         data->cntlid = cpu_to_le16(0xffff);
 376         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
 377         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
 378
 379         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &cqe,
 380                         data, sizeof(*data), 0, NVME_QID_ANY, 1,
 381                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
 382         if (ret) {
 383                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(cqe.result),
 384                                        &cmd, data);
 385                 goto out_free_data;
 386         }
 387
 388         ctrl->cntlid = le16_to_cpu(cqe.result16);
 389
 390 out_free_data:
 391         kfree(data);
 392         return ret;
 393 }
 394 EXPORT_SYMBOL_GPL(nvmf_connect_admin_queue);
 395
 396 /**
 397  * nvmf_connect_io_queue() - NVMe Fabrics I/O Queue "Connect"
 398  *                           API function.
 399  * @ctrl:       Host nvme controller instance used to establish an
 400  *              NVMe I/O queue connection to the already allocated NVMe
 401  *              controller on the target system.
 402  * @qid:        NVMe I/O queue number for the new I/O connection between
 403  *              host and target (note qid == 0 is illegal as this is
 404  *              the Admin queue, per NVMe standard).
 405  *
 406  * This function issues a fabrics-protocol connection
 407  * of a NVMe I/O queue (via NVMe Fabrics "Connect" command)
 408  * between the host system device and the allocated NVMe controller
 409  * on the target system.
 410  *
 411  * Return:
 412  *      0: success
 413  *      > 0: NVMe error status code
 414  *      < 0: Linux errno error code
 415  */
 416 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid)
 417 {
 418         struct nvme_command cmd;
 419         struct nvmf_connect_data *data;
 420         struct nvme_completion cqe;
 421         int ret;
 422
 423         memset(&cmd, 0, sizeof(cmd));
 424         cmd.connect.opcode = nvme_fabrics_command;
 425         cmd.connect.fctype = nvme_fabrics_type_connect;
 426         cmd.connect.qid = cpu_to_le16(qid);
 427         cmd.connect.sqsize = cpu_to_le16(ctrl->sqsize);
 428
 429         data = kzalloc(sizeof(*data), GFP_KERNEL);
 430         if (!data)
 431                 return -ENOMEM;
 432
 433         memcpy(&data->hostid, &ctrl->opts->host->id, sizeof(uuid_le));
 434         data->cntlid = cpu_to_le16(ctrl->cntlid);
 435         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
 436         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
 437
 438         ret = __nvme_submit_sync_cmd(ctrl->connect_q, &cmd, &cqe,
 439                         data, sizeof(*data), 0, qid, 1,
 440                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
 441         if (ret) {
 442                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(cqe.result),
 443                                        &cmd, data);
 444         }
 445         kfree(data);
 446         return ret;
 447 }
 448 EXPORT_SYMBOL_GPL(nvmf_connect_io_queue);
 449
 450 /**
 451  * nvmf_register_transport() - NVMe Fabrics Library registration function.
 452  * @ops:        Transport ops instance to be registered to the
 453  *              common fabrics library.
 454  *
 455  * API function that registers the type of specific transport fabric
 456  * being implemented to the common NVMe fabrics library. Part of
 457  * the overall init sequence of starting up a fabrics driver.
 458  */
 459 void nvmf_register_transport(struct nvmf_transport_ops *ops)
 460 {
 461         mutex_lock(&nvmf_transports_mutex);
 462         list_add_tail(&ops->entry, &nvmf_transports);
 463         mutex_unlock(&nvmf_transports_mutex);
 464 }
 465 EXPORT_SYMBOL_GPL(nvmf_register_transport);
 466
 467 /**
 468  * nvmf_unregister_transport() - NVMe Fabrics Library unregistration function.
 469  * @ops:        Transport ops instance to be unregistered from the
 470  *              common fabrics library.
 471  *
 472  * Fabrics API function that unregisters the type of specific transport
 473  * fabric being implemented from the common NVMe fabrics library.
 474  * Part of the overall exit sequence of unloading the implemented driver.
 475  */
 476 void nvmf_unregister_transport(struct nvmf_transport_ops *ops)
 477 {
 478         mutex_lock(&nvmf_transports_mutex);
 479         list_del(&ops->entry);
 480         mutex_unlock(&nvmf_transports_mutex);
 481 }
 482 EXPORT_SYMBOL_GPL(nvmf_unregister_transport);
 483
 484 static struct nvmf_transport_ops *nvmf_lookup_transport(
 485                 struct nvmf_ctrl_options *opts)
 486 {
 487         struct nvmf_transport_ops *ops;
 488
 489         lockdep_assert_held(&nvmf_transports_mutex);
 490
 491         list_for_each_entry(ops, &nvmf_transports, entry) {
 492                 if (strcmp(ops->name, opts->transport) == 0)
 493                         return ops;
 494         }
 495
 496         return NULL;
 497 }
 498
 499 static const match_table_t opt_tokens = {
 500         { NVMF_OPT_TRANSPORT,           "transport=%s"          },
 501         { NVMF_OPT_TRADDR,              "traddr=%s"             },
 502         { NVMF_OPT_TRSVCID,             "trsvcid=%s"            },
 503         { NVMF_OPT_NQN,                 "nqn=%s"                },
 504         { NVMF_OPT_QUEUE_SIZE,          "queue_size=%d"         },
 505         { NVMF_OPT_NR_IO_QUEUES,        "nr_io_queues=%d"       },
 506         { NVMF_OPT_RECONNECT_DELAY,     "reconnect_delay=%d"    },
 507         { NVMF_OPT_KATO,                "keep_alive_tmo=%d"     },
 508         { NVMF_OPT_HOSTNQN,             "hostnqn=%s"            },
 509         { NVMF_OPT_ERR,                 NULL                    }
 510 };
 511
 512 static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
 513                 const char *buf)
 514 {
 515         substring_t args[MAX_OPT_ARGS];
 516         char *options, *o, *p;
 517         int token, ret = 0;
 518         size_t nqnlen  = 0;
 519
 520         /* Set defaults */
 521         opts->queue_size = NVMF_DEF_QUEUE_SIZE;
 522         opts->nr_io_queues = num_online_cpus();
 523         opts->reconnect_delay = NVMF_DEF_RECONNECT_DELAY;
 524
 525         options = o = kstrdup(buf, GFP_KERNEL);
 526         if (!options)
 527                 return -ENOMEM;
 528
 529         while ((p = strsep(&o, ",\n")) != NULL) {
 530                 if (!*p)
 531                         continue;
 532
 533                 token = match_token(p, opt_tokens, args);
 534                 opts->mask |= token;
 535                 switch (token) {
 536                 case NVMF_OPT_TRANSPORT:
 537                         p = match_strdup(args);
 538                         if (!p) {
 539                                 ret = -ENOMEM;
 540                                 goto out;
 541                         }
 542                         opts->transport = p;
 543                         break;
 544                 case NVMF_OPT_NQN:
 545                         p = match_strdup(args);
 546                         if (!p) {
 547                                 ret = -ENOMEM;
 548                                 goto out;
 549                         }
 550                         opts->subsysnqn = p;
 551                         nqnlen = strlen(opts->subsysnqn);
 552                         if (nqnlen >= NVMF_NQN_SIZE) {
 553                                 pr_err("%s needs to be < %d bytes\n",
 554                                 opts->subsysnqn, NVMF_NQN_SIZE);
 555                                 ret = -EINVAL;
 556                                 goto out;
 557                         }
 558                         opts->discovery_nqn =
 559                                 !(strcmp(opts->subsysnqn,
 560                                          NVME_DISC_SUBSYS_NAME));
 561                         if (opts->discovery_nqn)
 562                                 opts->nr_io_queues = 0;
 563                         break;
 564                 case NVMF_OPT_TRADDR:
 565                         p = match_strdup(args);
 566                         if (!p) {
 567                                 ret = -ENOMEM;
 568                                 goto out;
 569                         }
 570                         opts->traddr = p;
 571                         break;
 572                 case NVMF_OPT_TRSVCID:
 573                         p = match_strdup(args);
 574                         if (!p) {
 575                                 ret = -ENOMEM;
 576                                 goto out;
 577                         }
 578                         opts->trsvcid = p;
 579                         break;
 580                 case NVMF_OPT_QUEUE_SIZE:
 581                         if (match_int(args, &token)) {
 582                                 ret = -EINVAL;
 583                                 goto out;
 584                         }
 585                         if (token < NVMF_MIN_QUEUE_SIZE ||
 586                             token > NVMF_MAX_QUEUE_SIZE) {
 587                                 pr_err("Invalid queue_size %d\n", token);
 588                                 ret = -EINVAL;
 589                                 goto out;
 590                         }
 591                         opts->queue_size = token;
 592                         break;
 593                 case NVMF_OPT_NR_IO_QUEUES:
 594                         if (match_int(args, &token)) {
 595                                 ret = -EINVAL;
 596                                 goto out;
 597                         }
 598                         if (token <= 0) {
 599                                 pr_err("Invalid number of IOQs %d\n", token);
 600                                 ret = -EINVAL;
 601                                 goto out;
 602                         }
 603                         opts->nr_io_queues = min_t(unsigned int,
 604                                         num_online_cpus(), token);
 605                         break;
 606                 case NVMF_OPT_KATO:
 607                         if (match_int(args, &token)) {
 608                                 ret = -EINVAL;
 609                                 goto out;
 610                         }
 611
 612                         if (opts->discovery_nqn) {
 613                                 pr_err("Discovery controllers cannot accept keep_alive_tmo != 0\n");
 614                                 ret = -EINVAL;
 615                                 goto out;
 616                         }
 617
 618                         if (token < 0) {
 619                                 pr_err("Invalid keep_alive_tmo %d\n", token);
 620                                 ret = -EINVAL;
 621                                 goto out;
 622                         } else if (token == 0) {
 623                                 /* Allowed for debug */
 624                                 pr_warn("keep_alive_tmo 0 won't execute keep alives!!!\n");
 625                         }
 626                         opts->kato = token;
 627                         break;
 628                 case NVMF_OPT_HOSTNQN:
 629                         if (opts->host) {
 630                                 pr_err("hostnqn already user-assigned: %s\n",
 631                                        opts->host->nqn);
 632                                 ret = -EADDRINUSE;
 633                                 goto out;
 634                         }
 635                         p = match_strdup(args);
 636                         if (!p) {
 637                                 ret = -ENOMEM;
 638                                 goto out;
 639                         }
 640                         nqnlen = strlen(p);
 641                         if (nqnlen >= NVMF_NQN_SIZE) {
 642                                 pr_err("%s needs to be < %d bytes\n",
 643                                         p, NVMF_NQN_SIZE);
 644                                 ret = -EINVAL;
 645                                 goto out;
 646                         }
 647                         opts->host = nvmf_host_add(p);
 648                         if (!opts->host) {
 649                                 ret = -ENOMEM;
 650                                 goto out;
 651                         }
 652                         break;
 653                 case NVMF_OPT_RECONNECT_DELAY:
 654                         if (match_int(args, &token)) {
 655                                 ret = -EINVAL;
 656                                 goto out;
 657                         }
 658                         if (token <= 0) {
 659                                 pr_err("Invalid reconnect_delay %d\n", token);
 660                                 ret = -EINVAL;
 661                                 goto out;
 662                         }
 663                         opts->reconnect_delay = token;
 664                         break;
 665                 default:
 666                         pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
 667                                 p);
 668                         ret = -EINVAL;
 669                         goto out;
 670                 }
 671         }
 672
 673         if (!opts->host) {
 674                 kref_get(&nvmf_default_host->ref);
 675                 opts->host = nvmf_default_host;
 676         }
 677
 678 out:
 679         if (!opts->discovery_nqn && !opts->kato)
 680                 opts->kato = NVME_DEFAULT_KATO;
 681         kfree(options);
 682         return ret;
 683 }
 684
 685 static int nvmf_check_required_opts(struct nvmf_ctrl_options *opts,
 686                 unsigned int required_opts)
 687 {
 688         if ((opts->mask & required_opts) != required_opts) {
 689                 int i;
 690
 691                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
 692                         if ((opt_tokens[i].token & required_opts) &&
 693                             !(opt_tokens[i].token & opts->mask)) {
 694                                 pr_warn("missing parameter '%s'\n",
 695                                         opt_tokens[i].pattern);
 696                         }
 697                 }
 698
 699                 return -EINVAL;
 700         }
 701
 702         return 0;
 703 }
 704
 705 static int nvmf_check_allowed_opts(struct nvmf_ctrl_options *opts,
 706                 unsigned int allowed_opts)
 707 {
 708         if (opts->mask & ~allowed_opts) {
 709                 int i;
 710
 711                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
 712                         if (opt_tokens[i].token & ~allowed_opts) {
 713                                 pr_warn("invalid parameter '%s'\n",
 714                                         opt_tokens[i].pattern);
 715                         }
 716                 }
 717
 718                 return -EINVAL;
 719         }
 720
 721         return 0;
 722 }
 723
 724 void nvmf_free_options(struct nvmf_ctrl_options *opts)
 725 {
 726         nvmf_host_put(opts->host);
 727         kfree(opts->transport);
 728         kfree(opts->traddr);
 729         kfree(opts->trsvcid);
 730         kfree(opts->subsysnqn);
 731         kfree(opts);
 732 }
 733 EXPORT_SYMBOL_GPL(nvmf_free_options);
 734
 735 #define NVMF_REQUIRED_OPTS      (NVMF_OPT_TRANSPORT | NVMF_OPT_NQN)
 736 #define NVMF_ALLOWED_OPTS       (NVMF_OPT_QUEUE_SIZE | NVMF_OPT_NR_IO_QUEUES | \
 737                                  NVMF_OPT_KATO | NVMF_OPT_HOSTNQN)
 738
 739 static struct nvme_ctrl *
 740 nvmf_create_ctrl(struct device *dev, const char *buf, size_t count)
 741 {
 742         struct nvmf_ctrl_options *opts;
 743         struct nvmf_transport_ops *ops;
 744         struct nvme_ctrl *ctrl;
 745         int ret;
 746
 747         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 748         if (!opts)
 749                 return ERR_PTR(-ENOMEM);
 750
 751         ret = nvmf_parse_options(opts, buf);
 752         if (ret)
 753                 goto out_free_opts;
 754
 755         /*
 756          * Check the generic options first as we need a valid transport for
 757          * the lookup below.  Then clear the generic flags so that transport
 758          * drivers don't have to care about them.
 759          */
 760         ret = nvmf_check_required_opts(opts, NVMF_REQUIRED_OPTS);
 761         if (ret)
 762                 goto out_free_opts;
 763         opts->mask &= ~NVMF_REQUIRED_OPTS;
 764
 765         mutex_lock(&nvmf_transports_mutex);
 766         ops = nvmf_lookup_transport(opts);
 767         if (!ops) {
 768                 pr_info("no handler found for transport %s.\n",
 769                         opts->transport);
 770                 ret = -EINVAL;
 771                 goto out_unlock;
 772         }
 773
 774         ret = nvmf_check_required_opts(opts, ops->required_opts);
 775         if (ret)
 776                 goto out_unlock;
 777         ret = nvmf_check_allowed_opts(opts, NVMF_ALLOWED_OPTS |
 778                                 ops->allowed_opts | ops->required_opts);
 779         if (ret)
 780                 goto out_unlock;
 781
 782         ctrl = ops->create_ctrl(dev, opts);
 783         if (IS_ERR(ctrl)) {
 784                 ret = PTR_ERR(ctrl);
 785                 goto out_unlock;
 786         }
 787
 788         mutex_unlock(&nvmf_transports_mutex);
 789         return ctrl;
 790
 791 out_unlock:
 792         mutex_unlock(&nvmf_transports_mutex);
 793 out_free_opts:
 794         nvmf_host_put(opts->host);
 795         kfree(opts);
 796         return ERR_PTR(ret);
 797 }
 798
 799 static struct class *nvmf_class;
 800 static struct device *nvmf_device;
 801 static DEFINE_MUTEX(nvmf_dev_mutex);
 802
 803 static ssize_t nvmf_dev_write(struct file *file, const char __user *ubuf,
 804                 size_t count, loff_t *pos)
 805 {
 806         struct seq_file *seq_file = file->private_data;
 807         struct nvme_ctrl *ctrl;
 808         const char *buf;
 809         int ret = 0;
 810
 811         if (count > PAGE_SIZE)
 812                 return -ENOMEM;
 813
 814         buf = memdup_user_nul(ubuf, count);
 815         if (IS_ERR(buf))
 816                 return PTR_ERR(buf);
 817
 818         mutex_lock(&nvmf_dev_mutex);
 819         if (seq_file->private) {
 820                 ret = -EINVAL;
 821                 goto out_unlock;
 822         }
 823
 824         ctrl = nvmf_create_ctrl(nvmf_device, buf, count);
 825         if (IS_ERR(ctrl)) {
 826                 ret = PTR_ERR(ctrl);
 827                 goto out_unlock;
 828         }
 829
 830         seq_file->private = ctrl;
 831
 832 out_unlock:
 833         mutex_unlock(&nvmf_dev_mutex);
 834         kfree(buf);
 835         return ret ? ret : count;
 836 }
 837
 838 static int nvmf_dev_show(struct seq_file *seq_file, void *private)
 839 {
 840         struct nvme_ctrl *ctrl;
 841         int ret = 0;
 842
 843         mutex_lock(&nvmf_dev_mutex);
 844         ctrl = seq_file->private;
 845         if (!ctrl) {
 846                 ret = -EINVAL;
 847                 goto out_unlock;
 848         }
 849
 850         seq_printf(seq_file, "instance=%d,cntlid=%d\n",
 851                         ctrl->instance, ctrl->cntlid);
 852
 853 out_unlock:
 854         mutex_unlock(&nvmf_dev_mutex);
 855         return ret;
 856 }
 857
 858 static int nvmf_dev_open(struct inode *inode, struct file *file)
 859 {
 860         /*
 861          * The miscdevice code initializes file->private_data, but doesn't
 862          * make use of it later.
 863          */
 864         file->private_data = NULL;
 865         return single_open(file, nvmf_dev_show, NULL);
 866 }
 867
 868 static int nvmf_dev_release(struct inode *inode, struct file *file)
 869 {
 870         struct seq_file *seq_file = file->private_data;
 871         struct nvme_ctrl *ctrl = seq_file->private;
 872
 873         if (ctrl)
 874                 nvme_put_ctrl(ctrl);
 875         return single_release(inode, file);
 876 }
 877
 878 static const struct file_operations nvmf_dev_fops = {
 879         .owner          = THIS_MODULE,
 880         .write          = nvmf_dev_write,
 881         .read           = seq_read,
 882         .open           = nvmf_dev_open,
 883         .release        = nvmf_dev_release,
 884 };
 885
 886 static struct miscdevice nvmf_misc = {
 887         .minor          = MISC_DYNAMIC_MINOR,
 888         .name           = "nvme-fabrics",
 889         .fops           = &nvmf_dev_fops,
 890 };
 891
 892 static int __init nvmf_init(void)
 893 {
 894         int ret;
 895
 896         nvmf_default_host = nvmf_host_default();
 897         if (!nvmf_default_host)
 898                 return -ENOMEM;
 899
 900         nvmf_class = class_create(THIS_MODULE, "nvme-fabrics");
 901         if (IS_ERR(nvmf_class)) {
 902                 pr_err("couldn't register class nvme-fabrics\n");
 903                 ret = PTR_ERR(nvmf_class);
 904                 goto out_free_host;
 905         }
 906
 907         nvmf_device =
 908                 device_create(nvmf_class, NULL, MKDEV(0, 0), NULL, "ctl");
 909         if (IS_ERR(nvmf_device)) {
 910                 pr_err("couldn't create nvme-fabris device!\n");
 911                 ret = PTR_ERR(nvmf_device);
 912                 goto out_destroy_class;
 913         }
 914
 915         ret = misc_register(&nvmf_misc);
 916         if (ret) {
 917                 pr_err("couldn't register misc device: %d\n", ret);
 918                 goto out_destroy_device;
 919         }
 920
 921         return 0;
 922
 923 out_destroy_device:
 924         device_destroy(nvmf_class, MKDEV(0, 0));
 925 out_destroy_class:
 926         class_destroy(nvmf_class);
 927 out_free_host:
 928         nvmf_host_put(nvmf_default_host);
 929         return ret;
 930 }
 931
 932 static void __exit nvmf_exit(void)
 933 {
 934         misc_deregister(&nvmf_misc);
 935         device_destroy(nvmf_class, MKDEV(0, 0));
 936         class_destroy(nvmf_class);
 937         nvmf_host_put(nvmf_default_host);
 938
 939         BUILD_BUG_ON(sizeof(struct nvmf_connect_command) != 64);
 940         BUILD_BUG_ON(sizeof(struct nvmf_property_get_command) != 64);
 941         BUILD_BUG_ON(sizeof(struct nvmf_property_set_command) != 64);
 942         BUILD_BUG_ON(sizeof(struct nvmf_connect_data) != 1024);
 943 }
 944
 945 MODULE_LICENSE("GPL v2");
 946
 947 module_init(nvmf_init);
 948 module_exit(nvmf_exit);