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                 kref_get(&host->ref);
  52                 goto out_unlock;
  53         }
  54
  55         host = kmalloc(sizeof(*host), GFP_KERNEL);
  56         if (!host)
  57                 goto out_unlock;
  58
  59         kref_init(&host->ref);
  60         memcpy(host->nqn, hostnqn, NVMF_NQN_SIZE);
  61         uuid_be_gen(&host->id);
  62
  63         list_add_tail(&host->list, &nvmf_hosts);
  64 out_unlock:
  65         mutex_unlock(&nvmf_hosts_mutex);
  66         return host;
  67 }
  68
  69 static struct nvmf_host *nvmf_host_default(void)
  70 {
  71         struct nvmf_host *host;
  72
  73         host = kmalloc(sizeof(*host), GFP_KERNEL);
  74         if (!host)
  75                 return NULL;
  76
  77         kref_init(&host->ref);
  78         uuid_be_gen(&host->id);
  79         snprintf(host->nqn, NVMF_NQN_SIZE,
  80                 "nqn.2014-08.org.nvmexpress:NVMf:uuid:%pUb", &host->id);
  81
  82         mutex_lock(&nvmf_hosts_mutex);
  83         list_add_tail(&host->list, &nvmf_hosts);
  84         mutex_unlock(&nvmf_hosts_mutex);
  85
  86         return host;
  87 }
  88
  89 static void nvmf_host_destroy(struct kref *ref)
  90 {
  91         struct nvmf_host *host = container_of(ref, struct nvmf_host, ref);
  92
  93         mutex_lock(&nvmf_hosts_mutex);
  94         list_del(&host->list);
  95         mutex_unlock(&nvmf_hosts_mutex);
  96
  97         kfree(host);
  98 }
  99
 100 static void nvmf_host_put(struct nvmf_host *host)
 101 {
 102         if (host)
 103                 kref_put(&host->ref, nvmf_host_destroy);
 104 }
 105
 106 /**
 107  * nvmf_get_address() -  Get address/port
 108  * @ctrl:       Host NVMe controller instance which we got the address
 109  * @buf:        OUTPUT parameter that will contain the address/port
 110  * @size:       buffer size
 111  */
 112 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
 113 {
 114         return snprintf(buf, size, "traddr=%s,trsvcid=%s\n",
 115                         ctrl->opts->traddr, ctrl->opts->trsvcid);
 116 }
 117 EXPORT_SYMBOL_GPL(nvmf_get_address);
 118
 119 /**
 120  * nvmf_get_subsysnqn() - Get subsystem NQN
 121  * @ctrl:       Host NVMe controller instance which we got the NQN
 122  */
 123 const char *nvmf_get_subsysnqn(struct nvme_ctrl *ctrl)
 124 {
 125         return ctrl->opts->subsysnqn;
 126 }
 127 EXPORT_SYMBOL_GPL(nvmf_get_subsysnqn);
 128
 129 /**
 130  * nvmf_reg_read32() -  NVMe Fabrics "Property Get" API function.
 131  * @ctrl:       Host NVMe controller instance maintaining the admin
 132  *              queue used to submit the property read command to
 133  *              the allocated NVMe controller resource on the target system.
 134  * @off:        Starting offset value of the targeted property
 135  *              register (see the fabrics section of the NVMe standard).
 136  * @val:        OUTPUT parameter that will contain the value of
 137  *              the property after a successful read.
 138  *
 139  * Used by the host system to retrieve a 32-bit capsule property value
 140  * from an NVMe controller on the target system.
 141  *
 142  * ("Capsule property" is an "PCIe register concept" applied to the
 143  * NVMe fabrics space.)
 144  *
 145  * Return:
 146  *      0: successful read
 147  *      > 0: NVMe error status code
 148  *      < 0: Linux errno error code
 149  */
 150 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
 151 {
 152         struct nvme_command cmd;
 153         struct nvme_completion cqe;
 154         int ret;
 155
 156         memset(&cmd, 0, sizeof(cmd));
 157         cmd.prop_get.opcode = nvme_fabrics_command;
 158         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
 159         cmd.prop_get.offset = cpu_to_le32(off);
 160
 161         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &cqe, NULL, 0, 0,
 162                         NVME_QID_ANY, 0, 0);
 163
 164         if (ret >= 0)
 165                 *val = le64_to_cpu(cqe.result64);
 166         if (unlikely(ret != 0))
 167                 dev_err(ctrl->device,
 168                         "Property Get error: %d, offset %#x\n",
 169                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 170
 171         return ret;
 172 }
 173 EXPORT_SYMBOL_GPL(nvmf_reg_read32);
 174
 175 /**
 176  * nvmf_reg_read64() -  NVMe Fabrics "Property Get" API function.
 177  * @ctrl:       Host NVMe controller instance maintaining the admin
 178  *              queue used to submit the property read command to
 179  *              the allocated controller resource on the target system.
 180  * @off:        Starting offset value of the targeted property
 181  *              register (see the fabrics section of the NVMe standard).
 182  * @val:        OUTPUT parameter that will contain the value of
 183  *              the property after a successful read.
 184  *
 185  * Used by the host system to retrieve a 64-bit capsule property value
 186  * from an NVMe controller on the target system.
 187  *
 188  * ("Capsule property" is an "PCIe register concept" applied to the
 189  * NVMe fabrics space.)
 190  *
 191  * Return:
 192  *      0: successful read
 193  *      > 0: NVMe error status code
 194  *      < 0: Linux errno error code
 195  */
 196 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
 197 {
 198         struct nvme_command cmd;
 199         struct nvme_completion cqe;
 200         int ret;
 201
 202         memset(&cmd, 0, sizeof(cmd));
 203         cmd.prop_get.opcode = nvme_fabrics_command;
 204         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
 205         cmd.prop_get.attrib = 1;
 206         cmd.prop_get.offset = cpu_to_le32(off);
 207
 208         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &cqe, NULL, 0, 0,
 209                         NVME_QID_ANY, 0, 0);
 210
 211         if (ret >= 0)
 212                 *val = le64_to_cpu(cqe.result64);
 213         if (unlikely(ret != 0))
 214                 dev_err(ctrl->device,
 215                         "Property Get error: %d, offset %#x\n",
 216                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 217         return ret;
 218 }
 219 EXPORT_SYMBOL_GPL(nvmf_reg_read64);
 220
 221 /**
 222  * nvmf_reg_write32() -  NVMe Fabrics "Property Write" API function.
 223  * @ctrl:       Host NVMe controller instance maintaining the admin
 224  *              queue used to submit the property read command to
 225  *              the allocated NVMe controller resource on the target system.
 226  * @off:        Starting offset value of the targeted property
 227  *              register (see the fabrics section of the NVMe standard).
 228  * @val:        Input parameter that contains the value to be
 229  *              written to the property.
 230  *
 231  * Used by the NVMe host system to write a 32-bit capsule property value
 232  * to an NVMe controller on the target system.
 233  *
 234  * ("Capsule property" is an "PCIe register concept" applied to the
 235  * NVMe fabrics space.)
 236  *
 237  * Return:
 238  *      0: successful write
 239  *      > 0: NVMe error status code
 240  *      < 0: Linux errno error code
 241  */
 242 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
 243 {
 244         struct nvme_command cmd;
 245         int ret;
 246
 247         memset(&cmd, 0, sizeof(cmd));
 248         cmd.prop_set.opcode = nvme_fabrics_command;
 249         cmd.prop_set.fctype = nvme_fabrics_type_property_set;
 250         cmd.prop_set.attrib = 0;
 251         cmd.prop_set.offset = cpu_to_le32(off);
 252         cmd.prop_set.value = cpu_to_le64(val);
 253
 254         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, NULL, NULL, 0, 0,
 255                         NVME_QID_ANY, 0, 0);
 256         if (unlikely(ret))
 257                 dev_err(ctrl->device,
 258                         "Property Set error: %d, offset %#x\n",
 259                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 260         return ret;
 261 }
 262 EXPORT_SYMBOL_GPL(nvmf_reg_write32);
 263
 264 /**
 265  * nvmf_log_connect_error() - Error-parsing-diagnostic print
 266  * out function for connect() errors.
 267  *
 268  * @ctrl: the specific /dev/nvmeX device that had the error.
 269  *
 270  * @errval: Error code to be decoded in a more human-friendly
 271  *          printout.
 272  *
 273  * @offset: For use with the NVMe error code NVME_SC_CONNECT_INVALID_PARAM.
 274  *
 275  * @cmd: This is the SQE portion of a submission capsule.
 276  *
 277  * @data: This is the "Data" portion of a submission capsule.
 278  */
 279 static void nvmf_log_connect_error(struct nvme_ctrl *ctrl,
 280                 int errval, int offset, struct nvme_command *cmd,
 281                 struct nvmf_connect_data *data)
 282 {
 283         int err_sctype = errval & (~NVME_SC_DNR);
 284
 285         switch (err_sctype) {
 286
 287         case (NVME_SC_CONNECT_INVALID_PARAM):
 288                 if (offset >> 16) {
 289                         char *inv_data = "Connect Invalid Data Parameter";
 290
 291                         switch (offset & 0xffff) {
 292                         case (offsetof(struct nvmf_connect_data, cntlid)):
 293                                 dev_err(ctrl->device,
 294                                         "%s, cntlid: %d\n",
 295                                         inv_data, data->cntlid);
 296                                 break;
 297                         case (offsetof(struct nvmf_connect_data, hostnqn)):
 298                                 dev_err(ctrl->device,
 299                                         "%s, hostnqn \"%s\"\n",
 300                                         inv_data, data->hostnqn);
 301                                 break;
 302                         case (offsetof(struct nvmf_connect_data, subsysnqn)):
 303                                 dev_err(ctrl->device,
 304                                         "%s, subsysnqn \"%s\"\n",
 305                                         inv_data, data->subsysnqn);
 306                                 break;
 307                         default:
 308                                 dev_err(ctrl->device,
 309                                         "%s, starting byte offset: %d\n",
 310                                        inv_data, offset & 0xffff);
 311                                 break;
 312                         }
 313                 } else {
 314                         char *inv_sqe = "Connect Invalid SQE Parameter";
 315
 316                         switch (offset) {
 317                         case (offsetof(struct nvmf_connect_command, qid)):
 318                                 dev_err(ctrl->device,
 319                                        "%s, qid %d\n",
 320                                         inv_sqe, cmd->connect.qid);
 321                                 break;
 322                         default:
 323                                 dev_err(ctrl->device,
 324                                         "%s, starting byte offset: %d\n",
 325                                         inv_sqe, offset);
 326                         }
 327                 }
 328                 break;
 329         default:
 330                 dev_err(ctrl->device,
 331                         "Connect command failed, error wo/DNR bit: %d\n",
 332                         err_sctype);
 333                 break;
 334         } /* switch (err_sctype) */
 335 }
 336
 337 /**
 338  * nvmf_connect_admin_queue() - NVMe Fabrics Admin Queue "Connect"
 339  *                              API function.
 340  * @ctrl:       Host nvme controller instance used to request
 341  *              a new NVMe controller allocation on the target
 342  *              system and  establish an NVMe Admin connection to
 343  *              that controller.
 344  *
 345  * This function enables an NVMe host device to request a new allocation of
 346  * an NVMe controller resource on a target system as well establish a
 347  * fabrics-protocol connection of the NVMe Admin queue between the
 348  * host system device and the allocated NVMe controller on the
 349  * target system via a NVMe Fabrics "Connect" command.
 350  *
 351  * Return:
 352  *      0: success
 353  *      > 0: NVMe error status code
 354  *      < 0: Linux errno error code
 355  *
 356  */
 357 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
 358 {
 359         struct nvme_command cmd;
 360         struct nvme_completion cqe;
 361         struct nvmf_connect_data *data;
 362         int ret;
 363
 364         memset(&cmd, 0, sizeof(cmd));
 365         cmd.connect.opcode = nvme_fabrics_command;
 366         cmd.connect.fctype = nvme_fabrics_type_connect;
 367         cmd.connect.qid = 0;
 368
 369         /*
 370          * fabrics spec sets a minimum of depth 32 for admin queue,
 371          * so set the queue with this depth always until
 372          * justification otherwise.
 373          */
 374         cmd.connect.sqsize = cpu_to_le16(NVMF_AQ_DEPTH - 1);
 375
 376         /*
 377          * Set keep-alive timeout in seconds granularity (ms * 1000)
 378          * and add a grace period for controller kato enforcement
 379          */
 380         cmd.connect.kato = ctrl->opts->discovery_nqn ? 0 :
 381                 cpu_to_le32((ctrl->kato + NVME_KATO_GRACE) * 1000);
 382
 383         data = kzalloc(sizeof(*data), GFP_KERNEL);
 384         if (!data)
 385                 return -ENOMEM;
 386
 387         memcpy(&data->hostid, &ctrl->opts->host->id, sizeof(uuid_be));
 388         data->cntlid = cpu_to_le16(0xffff);
 389         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
 390         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
 391
 392         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &cqe,
 393                         data, sizeof(*data), 0, NVME_QID_ANY, 1,
 394                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
 395         if (ret) {
 396                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(cqe.result),
 397                                        &cmd, data);
 398                 goto out_free_data;
 399         }
 400
 401         ctrl->cntlid = le16_to_cpu(cqe.result16);
 402
 403 out_free_data:
 404         kfree(data);
 405         return ret;
 406 }
 407 EXPORT_SYMBOL_GPL(nvmf_connect_admin_queue);
 408
 409 /**
 410  * nvmf_connect_io_queue() - NVMe Fabrics I/O Queue "Connect"
 411  *                           API function.
 412  * @ctrl:       Host nvme controller instance used to establish an
 413  *              NVMe I/O queue connection to the already allocated NVMe
 414  *              controller on the target system.
 415  * @qid:        NVMe I/O queue number for the new I/O connection between
 416  *              host and target (note qid == 0 is illegal as this is
 417  *              the Admin queue, per NVMe standard).
 418  *
 419  * This function issues a fabrics-protocol connection
 420  * of a NVMe I/O queue (via NVMe Fabrics "Connect" command)
 421  * between the host system device and the allocated NVMe controller
 422  * on the target system.
 423  *
 424  * Return:
 425  *      0: success
 426  *      > 0: NVMe error status code
 427  *      < 0: Linux errno error code
 428  */
 429 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid)
 430 {
 431         struct nvme_command cmd;
 432         struct nvmf_connect_data *data;
 433         struct nvme_completion cqe;
 434         int ret;
 435
 436         memset(&cmd, 0, sizeof(cmd));
 437         cmd.connect.opcode = nvme_fabrics_command;
 438         cmd.connect.fctype = nvme_fabrics_type_connect;
 439         cmd.connect.qid = cpu_to_le16(qid);
 440         cmd.connect.sqsize = cpu_to_le16(ctrl->sqsize);
 441
 442         data = kzalloc(sizeof(*data), GFP_KERNEL);
 443         if (!data)
 444                 return -ENOMEM;
 445
 446         memcpy(&data->hostid, &ctrl->opts->host->id, sizeof(uuid_be));
 447         data->cntlid = cpu_to_le16(ctrl->cntlid);
 448         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
 449         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
 450
 451         ret = __nvme_submit_sync_cmd(ctrl->connect_q, &cmd, &cqe,
 452                         data, sizeof(*data), 0, qid, 1,
 453                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
 454         if (ret) {
 455                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(cqe.result),
 456                                        &cmd, data);
 457         }
 458         kfree(data);
 459         return ret;
 460 }
 461 EXPORT_SYMBOL_GPL(nvmf_connect_io_queue);
 462
 463 /**
 464  * nvmf_register_transport() - NVMe Fabrics Library registration function.
 465  * @ops:        Transport ops instance to be registered to the
 466  *              common fabrics library.
 467  *
 468  * API function that registers the type of specific transport fabric
 469  * being implemented to the common NVMe fabrics library. Part of
 470  * the overall init sequence of starting up a fabrics driver.
 471  */
 472 void nvmf_register_transport(struct nvmf_transport_ops *ops)
 473 {
 474         mutex_lock(&nvmf_transports_mutex);
 475         list_add_tail(&ops->entry, &nvmf_transports);
 476         mutex_unlock(&nvmf_transports_mutex);
 477 }
 478 EXPORT_SYMBOL_GPL(nvmf_register_transport);
 479
 480 /**
 481  * nvmf_unregister_transport() - NVMe Fabrics Library unregistration function.
 482  * @ops:        Transport ops instance to be unregistered from the
 483  *              common fabrics library.
 484  *
 485  * Fabrics API function that unregisters the type of specific transport
 486  * fabric being implemented from the common NVMe fabrics library.
 487  * Part of the overall exit sequence of unloading the implemented driver.
 488  */
 489 void nvmf_unregister_transport(struct nvmf_transport_ops *ops)
 490 {
 491         mutex_lock(&nvmf_transports_mutex);
 492         list_del(&ops->entry);
 493         mutex_unlock(&nvmf_transports_mutex);
 494 }
 495 EXPORT_SYMBOL_GPL(nvmf_unregister_transport);
 496
 497 static struct nvmf_transport_ops *nvmf_lookup_transport(
 498                 struct nvmf_ctrl_options *opts)
 499 {
 500         struct nvmf_transport_ops *ops;
 501
 502         lockdep_assert_held(&nvmf_transports_mutex);
 503
 504         list_for_each_entry(ops, &nvmf_transports, entry) {
 505                 if (strcmp(ops->name, opts->transport) == 0)
 506                         return ops;
 507         }
 508
 509         return NULL;
 510 }
 511
 512 static const match_table_t opt_tokens = {
 513         { NVMF_OPT_TRANSPORT,           "transport=%s"          },
 514         { NVMF_OPT_TRADDR,              "traddr=%s"             },
 515         { NVMF_OPT_TRSVCID,             "trsvcid=%s"            },
 516         { NVMF_OPT_NQN,                 "nqn=%s"                },
 517         { NVMF_OPT_QUEUE_SIZE,          "queue_size=%d"         },
 518         { NVMF_OPT_NR_IO_QUEUES,        "nr_io_queues=%d"       },
 519         { NVMF_OPT_RECONNECT_DELAY,     "reconnect_delay=%d"    },
 520         { NVMF_OPT_KATO,                "keep_alive_tmo=%d"     },
 521         { NVMF_OPT_HOSTNQN,             "hostnqn=%s"            },
 522         { NVMF_OPT_ERR,                 NULL                    }
 523 };
 524
 525 static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
 526                 const char *buf)
 527 {
 528         substring_t args[MAX_OPT_ARGS];
 529         char *options, *o, *p;
 530         int token, ret = 0;
 531         size_t nqnlen  = 0;
 532
 533         /* Set defaults */
 534         opts->queue_size = NVMF_DEF_QUEUE_SIZE;
 535         opts->nr_io_queues = num_online_cpus();
 536         opts->reconnect_delay = NVMF_DEF_RECONNECT_DELAY;
 537
 538         options = o = kstrdup(buf, GFP_KERNEL);
 539         if (!options)
 540                 return -ENOMEM;
 541
 542         while ((p = strsep(&o, ",\n")) != NULL) {
 543                 if (!*p)
 544                         continue;
 545
 546                 token = match_token(p, opt_tokens, args);
 547                 opts->mask |= token;
 548                 switch (token) {
 549                 case NVMF_OPT_TRANSPORT:
 550                         p = match_strdup(args);
 551                         if (!p) {
 552                                 ret = -ENOMEM;
 553                                 goto out;
 554                         }
 555                         opts->transport = p;
 556                         break;
 557                 case NVMF_OPT_NQN:
 558                         p = match_strdup(args);
 559                         if (!p) {
 560                                 ret = -ENOMEM;
 561                                 goto out;
 562                         }
 563                         opts->subsysnqn = p;
 564                         nqnlen = strlen(opts->subsysnqn);
 565                         if (nqnlen >= NVMF_NQN_SIZE) {
 566                                 pr_err("%s needs to be < %d bytes\n",
 567                                 opts->subsysnqn, NVMF_NQN_SIZE);
 568                                 ret = -EINVAL;
 569                                 goto out;
 570                         }
 571                         opts->discovery_nqn =
 572                                 !(strcmp(opts->subsysnqn,
 573                                          NVME_DISC_SUBSYS_NAME));
 574                         if (opts->discovery_nqn)
 575                                 opts->nr_io_queues = 0;
 576                         break;
 577                 case NVMF_OPT_TRADDR:
 578                         p = match_strdup(args);
 579                         if (!p) {
 580                                 ret = -ENOMEM;
 581                                 goto out;
 582                         }
 583                         opts->traddr = p;
 584                         break;
 585                 case NVMF_OPT_TRSVCID:
 586                         p = match_strdup(args);
 587                         if (!p) {
 588                                 ret = -ENOMEM;
 589                                 goto out;
 590                         }
 591                         opts->trsvcid = p;
 592                         break;
 593                 case NVMF_OPT_QUEUE_SIZE:
 594                         if (match_int(args, &token)) {
 595                                 ret = -EINVAL;
 596                                 goto out;
 597                         }
 598                         if (token < NVMF_MIN_QUEUE_SIZE ||
 599                             token > NVMF_MAX_QUEUE_SIZE) {
 600                                 pr_err("Invalid queue_size %d\n", token);
 601                                 ret = -EINVAL;
 602                                 goto out;
 603                         }
 604                         opts->queue_size = token;
 605                         break;
 606                 case NVMF_OPT_NR_IO_QUEUES:
 607                         if (match_int(args, &token)) {
 608                                 ret = -EINVAL;
 609                                 goto out;
 610                         }
 611                         if (token <= 0) {
 612                                 pr_err("Invalid number of IOQs %d\n", token);
 613                                 ret = -EINVAL;
 614                                 goto out;
 615                         }
 616                         opts->nr_io_queues = min_t(unsigned int,
 617                                         num_online_cpus(), token);
 618                         break;
 619                 case NVMF_OPT_KATO:
 620                         if (match_int(args, &token)) {
 621                                 ret = -EINVAL;
 622                                 goto out;
 623                         }
 624
 625                         if (opts->discovery_nqn) {
 626                                 pr_err("Discovery controllers cannot accept keep_alive_tmo != 0\n");
 627                                 ret = -EINVAL;
 628                                 goto out;
 629                         }
 630
 631                         if (token < 0) {
 632                                 pr_err("Invalid keep_alive_tmo %d\n", token);
 633                                 ret = -EINVAL;
 634                                 goto out;
 635                         } else if (token == 0) {
 636                                 /* Allowed for debug */
 637                                 pr_warn("keep_alive_tmo 0 won't execute keep alives!!!\n");
 638                         }
 639                         opts->kato = token;
 640                         break;
 641                 case NVMF_OPT_HOSTNQN:
 642                         if (opts->host) {
 643                                 pr_err("hostnqn already user-assigned: %s\n",
 644                                        opts->host->nqn);
 645                                 ret = -EADDRINUSE;
 646                                 goto out;
 647                         }
 648                         p = match_strdup(args);
 649                         if (!p) {
 650                                 ret = -ENOMEM;
 651                                 goto out;
 652                         }
 653                         nqnlen = strlen(p);
 654                         if (nqnlen >= NVMF_NQN_SIZE) {
 655                                 pr_err("%s needs to be < %d bytes\n",
 656                                         p, NVMF_NQN_SIZE);
 657                                 ret = -EINVAL;
 658                                 goto out;
 659                         }
 660                         opts->host = nvmf_host_add(p);
 661                         if (!opts->host) {
 662                                 ret = -ENOMEM;
 663                                 goto out;
 664                         }
 665                         break;
 666                 case NVMF_OPT_RECONNECT_DELAY:
 667                         if (match_int(args, &token)) {
 668                                 ret = -EINVAL;
 669                                 goto out;
 670                         }
 671                         if (token <= 0) {
 672                                 pr_err("Invalid reconnect_delay %d\n", token);
 673                                 ret = -EINVAL;
 674                                 goto out;
 675                         }
 676                         opts->reconnect_delay = token;
 677                         break;
 678                 default:
 679                         pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
 680                                 p);
 681                         ret = -EINVAL;
 682                         goto out;
 683                 }
 684         }
 685
 686         if (!opts->host) {
 687                 kref_get(&nvmf_default_host->ref);
 688                 opts->host = nvmf_default_host;
 689         }
 690
 691 out:
 692         if (!opts->discovery_nqn && !opts->kato)
 693                 opts->kato = NVME_DEFAULT_KATO;
 694         kfree(options);
 695         return ret;
 696 }
 697
 698 static int nvmf_check_required_opts(struct nvmf_ctrl_options *opts,
 699                 unsigned int required_opts)
 700 {
 701         if ((opts->mask & required_opts) != required_opts) {
 702                 int i;
 703
 704                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
 705                         if ((opt_tokens[i].token & required_opts) &&
 706                             !(opt_tokens[i].token & opts->mask)) {
 707                                 pr_warn("missing parameter '%s'\n",
 708                                         opt_tokens[i].pattern);
 709                         }
 710                 }
 711
 712                 return -EINVAL;
 713         }
 714
 715         return 0;
 716 }
 717
 718 static int nvmf_check_allowed_opts(struct nvmf_ctrl_options *opts,
 719                 unsigned int allowed_opts)
 720 {
 721         if (opts->mask & ~allowed_opts) {
 722                 int i;
 723
 724                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
 725                         if (opt_tokens[i].token & ~allowed_opts) {
 726                                 pr_warn("invalid parameter '%s'\n",
 727                                         opt_tokens[i].pattern);
 728                         }
 729                 }
 730
 731                 return -EINVAL;
 732         }
 733
 734         return 0;
 735 }
 736
 737 void nvmf_free_options(struct nvmf_ctrl_options *opts)
 738 {
 739         nvmf_host_put(opts->host);
 740         kfree(opts->transport);
 741         kfree(opts->traddr);
 742         kfree(opts->trsvcid);
 743         kfree(opts->subsysnqn);
 744         kfree(opts);
 745 }
 746 EXPORT_SYMBOL_GPL(nvmf_free_options);
 747
 748 #define NVMF_REQUIRED_OPTS      (NVMF_OPT_TRANSPORT | NVMF_OPT_NQN)
 749 #define NVMF_ALLOWED_OPTS       (NVMF_OPT_QUEUE_SIZE | NVMF_OPT_NR_IO_QUEUES | \
 750                                  NVMF_OPT_KATO | NVMF_OPT_HOSTNQN)
 751
 752 static struct nvme_ctrl *
 753 nvmf_create_ctrl(struct device *dev, const char *buf, size_t count)
 754 {
 755         struct nvmf_ctrl_options *opts;
 756         struct nvmf_transport_ops *ops;
 757         struct nvme_ctrl *ctrl;
 758         int ret;
 759
 760         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 761         if (!opts)
 762                 return ERR_PTR(-ENOMEM);
 763
 764         ret = nvmf_parse_options(opts, buf);
 765         if (ret)
 766                 goto out_free_opts;
 767
 768         /*
 769          * Check the generic options first as we need a valid transport for
 770          * the lookup below.  Then clear the generic flags so that transport
 771          * drivers don't have to care about them.
 772          */
 773         ret = nvmf_check_required_opts(opts, NVMF_REQUIRED_OPTS);
 774         if (ret)
 775                 goto out_free_opts;
 776         opts->mask &= ~NVMF_REQUIRED_OPTS;
 777
 778         mutex_lock(&nvmf_transports_mutex);
 779         ops = nvmf_lookup_transport(opts);
 780         if (!ops) {
 781                 pr_info("no handler found for transport %s.\n",
 782                         opts->transport);
 783                 ret = -EINVAL;
 784                 goto out_unlock;
 785         }
 786
 787         ret = nvmf_check_required_opts(opts, ops->required_opts);
 788         if (ret)
 789                 goto out_unlock;
 790         ret = nvmf_check_allowed_opts(opts, NVMF_ALLOWED_OPTS |
 791                                 ops->allowed_opts | ops->required_opts);
 792         if (ret)
 793                 goto out_unlock;
 794
 795         ctrl = ops->create_ctrl(dev, opts);
 796         if (IS_ERR(ctrl)) {
 797                 ret = PTR_ERR(ctrl);
 798                 goto out_unlock;
 799         }
 800
 801         mutex_unlock(&nvmf_transports_mutex);
 802         return ctrl;
 803
 804 out_unlock:
 805         mutex_unlock(&nvmf_transports_mutex);
 806 out_free_opts:
 807         nvmf_host_put(opts->host);
 808         kfree(opts);
 809         return ERR_PTR(ret);
 810 }
 811
 812 static struct class *nvmf_class;
 813 static struct device *nvmf_device;
 814 static DEFINE_MUTEX(nvmf_dev_mutex);
 815
 816 static ssize_t nvmf_dev_write(struct file *file, const char __user *ubuf,
 817                 size_t count, loff_t *pos)
 818 {
 819         struct seq_file *seq_file = file->private_data;
 820         struct nvme_ctrl *ctrl;
 821         const char *buf;
 822         int ret = 0;
 823
 824         if (count > PAGE_SIZE)
 825                 return -ENOMEM;
 826
 827         buf = memdup_user_nul(ubuf, count);
 828         if (IS_ERR(buf))
 829                 return PTR_ERR(buf);
 830
 831         mutex_lock(&nvmf_dev_mutex);
 832         if (seq_file->private) {
 833                 ret = -EINVAL;
 834                 goto out_unlock;
 835         }
 836
 837         ctrl = nvmf_create_ctrl(nvmf_device, buf, count);
 838         if (IS_ERR(ctrl)) {
 839                 ret = PTR_ERR(ctrl);
 840                 goto out_unlock;
 841         }
 842
 843         seq_file->private = ctrl;
 844
 845 out_unlock:
 846         mutex_unlock(&nvmf_dev_mutex);
 847         kfree(buf);
 848         return ret ? ret : count;
 849 }
 850
 851 static int nvmf_dev_show(struct seq_file *seq_file, void *private)
 852 {
 853         struct nvme_ctrl *ctrl;
 854         int ret = 0;
 855
 856         mutex_lock(&nvmf_dev_mutex);
 857         ctrl = seq_file->private;
 858         if (!ctrl) {
 859                 ret = -EINVAL;
 860                 goto out_unlock;
 861         }
 862
 863         seq_printf(seq_file, "instance=%d,cntlid=%d\n",
 864                         ctrl->instance, ctrl->cntlid);
 865
 866 out_unlock:
 867         mutex_unlock(&nvmf_dev_mutex);
 868         return ret;
 869 }
 870
 871 static int nvmf_dev_open(struct inode *inode, struct file *file)
 872 {
 873         /*
 874          * The miscdevice code initializes file->private_data, but doesn't
 875          * make use of it later.
 876          */
 877         file->private_data = NULL;
 878         return single_open(file, nvmf_dev_show, NULL);
 879 }
 880
 881 static int nvmf_dev_release(struct inode *inode, struct file *file)
 882 {
 883         struct seq_file *seq_file = file->private_data;
 884         struct nvme_ctrl *ctrl = seq_file->private;
 885
 886         if (ctrl)
 887                 nvme_put_ctrl(ctrl);
 888         return single_release(inode, file);
 889 }
 890
 891 static const struct file_operations nvmf_dev_fops = {
 892         .owner          = THIS_MODULE,
 893         .write          = nvmf_dev_write,
 894         .read           = seq_read,
 895         .open           = nvmf_dev_open,
 896         .release        = nvmf_dev_release,
 897 };
 898
 899 static struct miscdevice nvmf_misc = {
 900         .minor          = MISC_DYNAMIC_MINOR,
 901         .name           = "nvme-fabrics",
 902         .fops           = &nvmf_dev_fops,
 903 };
 904
 905 static int __init nvmf_init(void)
 906 {
 907         int ret;
 908
 909         nvmf_default_host = nvmf_host_default();
 910         if (!nvmf_default_host)
 911                 return -ENOMEM;
 912
 913         nvmf_class = class_create(THIS_MODULE, "nvme-fabrics");
 914         if (IS_ERR(nvmf_class)) {
 915                 pr_err("couldn't register class nvme-fabrics\n");
 916                 ret = PTR_ERR(nvmf_class);
 917                 goto out_free_host;
 918         }
 919
 920         nvmf_device =
 921                 device_create(nvmf_class, NULL, MKDEV(0, 0), NULL, "ctl");
 922         if (IS_ERR(nvmf_device)) {
 923                 pr_err("couldn't create nvme-fabris device!\n");
 924                 ret = PTR_ERR(nvmf_device);
 925                 goto out_destroy_class;
 926         }
 927
 928         ret = misc_register(&nvmf_misc);
 929         if (ret) {
 930                 pr_err("couldn't register misc device: %d\n", ret);
 931                 goto out_destroy_device;
 932         }
 933
 934         return 0;
 935
 936 out_destroy_device:
 937         device_destroy(nvmf_class, MKDEV(0, 0));
 938 out_destroy_class:
 939         class_destroy(nvmf_class);
 940 out_free_host:
 941         nvmf_host_put(nvmf_default_host);
 942         return ret;
 943 }
 944
 945 static void __exit nvmf_exit(void)
 946 {
 947         misc_deregister(&nvmf_misc);
 948         device_destroy(nvmf_class, MKDEV(0, 0));
 949         class_destroy(nvmf_class);
 950         nvmf_host_put(nvmf_default_host);
 951
 952         BUILD_BUG_ON(sizeof(struct nvmf_connect_command) != 64);
 953         BUILD_BUG_ON(sizeof(struct nvmf_property_get_command) != 64);
 954         BUILD_BUG_ON(sizeof(struct nvmf_property_set_command) != 64);
 955         BUILD_BUG_ON(sizeof(struct nvmf_connect_data) != 1024);
 956 }
 957
 958 MODULE_LICENSE("GPL v2");
 959
 960 module_init(nvmf_init);
 961 module_exit(nvmf_exit);