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
  62         list_add_tail(&host->list, &nvmf_hosts);
  63 out_unlock:
  64         mutex_unlock(&nvmf_hosts_mutex);
  65         return host;
  66 }
  67
  68 static struct nvmf_host *nvmf_host_default(void)
  69 {
  70         struct nvmf_host *host;
  71
  72         host = kmalloc(sizeof(*host), GFP_KERNEL);
  73         if (!host)
  74                 return NULL;
  75
  76         kref_init(&host->ref);
  77         snprintf(host->nqn, NVMF_NQN_SIZE,
  78                 "nqn.2014-08.org.nvmexpress:NVMf:uuid:%pUb", &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         mutex_lock(&nvmf_hosts_mutex);
  92         list_del(&host->list);
  93         mutex_unlock(&nvmf_hosts_mutex);
  94
  95         kfree(host);
  96 }
  97
  98 static void nvmf_host_put(struct nvmf_host *host)
  99 {
 100         if (host)
 101                 kref_put(&host->ref, nvmf_host_destroy);
 102 }
 103
 104 /**
 105  * nvmf_get_address() -  Get address/port
 106  * @ctrl:       Host NVMe controller instance which we got the address
 107  * @buf:        OUTPUT parameter that will contain the address/port
 108  * @size:       buffer size
 109  */
 110 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
 111 {
 112         int len = 0;
 113
 114         if (ctrl->opts->mask & NVMF_OPT_TRADDR)
 115                 len += snprintf(buf, size, "traddr=%s", ctrl->opts->traddr);
 116         if (ctrl->opts->mask & NVMF_OPT_TRSVCID)
 117                 len += snprintf(buf + len, size - len, "%strsvcid=%s",
 118                                 (len) ? "," : "", ctrl->opts->trsvcid);
 119         if (ctrl->opts->mask & NVMF_OPT_HOST_TRADDR)
 120                 len += snprintf(buf + len, size - len, "%shost_traddr=%s",
 121                                 (len) ? "," : "", ctrl->opts->host_traddr);
 122         len += snprintf(buf + len, size - len, "\n");
 123
 124         return len;
 125 }
 126 EXPORT_SYMBOL_GPL(nvmf_get_address);
 127
 128 /**
 129  * nvmf_reg_read32() -  NVMe Fabrics "Property Get" API function.
 130  * @ctrl:       Host NVMe controller instance maintaining the admin
 131  *              queue used to submit the property read command to
 132  *              the allocated NVMe controller resource on the target system.
 133  * @off:        Starting offset value of the targeted property
 134  *              register (see the fabrics section of the NVMe standard).
 135  * @val:        OUTPUT parameter that will contain the value of
 136  *              the property after a successful read.
 137  *
 138  * Used by the host system to retrieve a 32-bit capsule property value
 139  * from an NVMe controller on the target system.
 140  *
 141  * ("Capsule property" is an "PCIe register concept" applied to the
 142  * NVMe fabrics space.)
 143  *
 144  * Return:
 145  *      0: successful read
 146  *      > 0: NVMe error status code
 147  *      < 0: Linux errno error code
 148  */
 149 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
 150 {
 151         struct nvme_command cmd;
 152         union nvme_result res;
 153         int ret;
 154
 155         memset(&cmd, 0, sizeof(cmd));
 156         cmd.prop_get.opcode = nvme_fabrics_command;
 157         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
 158         cmd.prop_get.offset = cpu_to_le32(off);
 159
 160         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res, NULL, 0, 0,
 161                         NVME_QID_ANY, 0, 0);
 162
 163         if (ret >= 0)
 164                 *val = le64_to_cpu(res.u64);
 165         if (unlikely(ret != 0))
 166                 dev_err(ctrl->device,
 167                         "Property Get error: %d, offset %#x\n",
 168                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 169
 170         return ret;
 171 }
 172 EXPORT_SYMBOL_GPL(nvmf_reg_read32);
 173
 174 /**
 175  * nvmf_reg_read64() -  NVMe Fabrics "Property Get" API function.
 176  * @ctrl:       Host NVMe controller instance maintaining the admin
 177  *              queue used to submit the property read command to
 178  *              the allocated controller resource on the target system.
 179  * @off:        Starting offset value of the targeted property
 180  *              register (see the fabrics section of the NVMe standard).
 181  * @val:        OUTPUT parameter that will contain the value of
 182  *              the property after a successful read.
 183  *
 184  * Used by the host system to retrieve a 64-bit capsule property value
 185  * from an NVMe controller on the target system.
 186  *
 187  * ("Capsule property" is an "PCIe register concept" applied to the
 188  * NVMe fabrics space.)
 189  *
 190  * Return:
 191  *      0: successful read
 192  *      > 0: NVMe error status code
 193  *      < 0: Linux errno error code
 194  */
 195 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
 196 {
 197         struct nvme_command cmd;
 198         union nvme_result res;
 199         int ret;
 200
 201         memset(&cmd, 0, sizeof(cmd));
 202         cmd.prop_get.opcode = nvme_fabrics_command;
 203         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
 204         cmd.prop_get.attrib = 1;
 205         cmd.prop_get.offset = cpu_to_le32(off);
 206
 207         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res, NULL, 0, 0,
 208                         NVME_QID_ANY, 0, 0);
 209
 210         if (ret >= 0)
 211                 *val = le64_to_cpu(res.u64);
 212         if (unlikely(ret != 0))
 213                 dev_err(ctrl->device,
 214                         "Property Get error: %d, offset %#x\n",
 215                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 216         return ret;
 217 }
 218 EXPORT_SYMBOL_GPL(nvmf_reg_read64);
 219
 220 /**
 221  * nvmf_reg_write32() -  NVMe Fabrics "Property Write" API function.
 222  * @ctrl:       Host NVMe controller instance maintaining the admin
 223  *              queue used to submit the property read command to
 224  *              the allocated NVMe controller resource on the target system.
 225  * @off:        Starting offset value of the targeted property
 226  *              register (see the fabrics section of the NVMe standard).
 227  * @val:        Input parameter that contains the value to be
 228  *              written to the property.
 229  *
 230  * Used by the NVMe host system to write a 32-bit capsule property value
 231  * to an NVMe controller on the target system.
 232  *
 233  * ("Capsule property" is an "PCIe register concept" applied to the
 234  * NVMe fabrics space.)
 235  *
 236  * Return:
 237  *      0: successful write
 238  *      > 0: NVMe error status code
 239  *      < 0: Linux errno error code
 240  */
 241 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
 242 {
 243         struct nvme_command cmd;
 244         int ret;
 245
 246         memset(&cmd, 0, sizeof(cmd));
 247         cmd.prop_set.opcode = nvme_fabrics_command;
 248         cmd.prop_set.fctype = nvme_fabrics_type_property_set;
 249         cmd.prop_set.attrib = 0;
 250         cmd.prop_set.offset = cpu_to_le32(off);
 251         cmd.prop_set.value = cpu_to_le64(val);
 252
 253         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, NULL, NULL, 0, 0,
 254                         NVME_QID_ANY, 0, 0);
 255         if (unlikely(ret))
 256                 dev_err(ctrl->device,
 257                         "Property Set error: %d, offset %#x\n",
 258                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 259         return ret;
 260 }
 261 EXPORT_SYMBOL_GPL(nvmf_reg_write32);
 262
 263 /**
 264  * nvmf_log_connect_error() - Error-parsing-diagnostic print
 265  * out function for connect() errors.
 266  *
 267  * @ctrl: the specific /dev/nvmeX device that had the error.
 268  *
 269  * @errval: Error code to be decoded in a more human-friendly
 270  *          printout.
 271  *
 272  * @offset: For use with the NVMe error code NVME_SC_CONNECT_INVALID_PARAM.
 273  *
 274  * @cmd: This is the SQE portion of a submission capsule.
 275  *
 276  * @data: This is the "Data" portion of a submission capsule.
 277  */
 278 static void nvmf_log_connect_error(struct nvme_ctrl *ctrl,
 279                 int errval, int offset, struct nvme_command *cmd,
 280                 struct nvmf_connect_data *data)
 281 {
 282         int err_sctype = errval & (~NVME_SC_DNR);
 283
 284         switch (err_sctype) {
 285
 286         case (NVME_SC_CONNECT_INVALID_PARAM):
 287                 if (offset >> 16) {
 288                         char *inv_data = "Connect Invalid Data Parameter";
 289
 290                         switch (offset & 0xffff) {
 291                         case (offsetof(struct nvmf_connect_data, cntlid)):
 292                                 dev_err(ctrl->device,
 293                                         "%s, cntlid: %d\n",
 294                                         inv_data, data->cntlid);
 295                                 break;
 296                         case (offsetof(struct nvmf_connect_data, hostnqn)):
 297                                 dev_err(ctrl->device,
 298                                         "%s, hostnqn \"%s\"\n",
 299                                         inv_data, data->hostnqn);
 300                                 break;
 301                         case (offsetof(struct nvmf_connect_data, subsysnqn)):
 302                                 dev_err(ctrl->device,
 303                                         "%s, subsysnqn \"%s\"\n",
 304                                         inv_data, data->subsysnqn);
 305                                 break;
 306                         default:
 307                                 dev_err(ctrl->device,
 308                                         "%s, starting byte offset: %d\n",
 309                                        inv_data, offset & 0xffff);
 310                                 break;
 311                         }
 312                 } else {
 313                         char *inv_sqe = "Connect Invalid SQE Parameter";
 314
 315                         switch (offset) {
 316                         case (offsetof(struct nvmf_connect_command, qid)):
 317                                 dev_err(ctrl->device,
 318                                        "%s, qid %d\n",
 319                                         inv_sqe, cmd->connect.qid);
 320                                 break;
 321                         default:
 322                                 dev_err(ctrl->device,
 323                                         "%s, starting byte offset: %d\n",
 324                                         inv_sqe, offset);
 325                         }
 326                 }
 327                 break;
 328
 329         case NVME_SC_CONNECT_INVALID_HOST:
 330                 dev_err(ctrl->device,
 331                         "Connect for subsystem %s is not allowed, hostnqn: %s\n",
 332                         data->subsysnqn, data->hostnqn);
 333                 break;
 334
 335         case NVME_SC_CONNECT_CTRL_BUSY:
 336                 dev_err(ctrl->device,
 337                         "Connect command failed: controller is busy or not available\n");
 338                 break;
 339
 340         case NVME_SC_CONNECT_FORMAT:
 341                 dev_err(ctrl->device,
 342                         "Connect incompatible format: %d",
 343                         cmd->connect.recfmt);
 344                 break;
 345
 346         default:
 347                 dev_err(ctrl->device,
 348                         "Connect command failed, error wo/DNR bit: %d\n",
 349                         err_sctype);
 350                 break;
 351         } /* switch (err_sctype) */
 352 }
 353
 354 /**
 355  * nvmf_connect_admin_queue() - NVMe Fabrics Admin Queue "Connect"
 356  *                              API function.
 357  * @ctrl:       Host nvme controller instance used to request
 358  *              a new NVMe controller allocation on the target
 359  *              system and  establish an NVMe Admin connection to
 360  *              that controller.
 361  *
 362  * This function enables an NVMe host device to request a new allocation of
 363  * an NVMe controller resource on a target system as well establish a
 364  * fabrics-protocol connection of the NVMe Admin queue between the
 365  * host system device and the allocated NVMe controller on the
 366  * target system via a NVMe Fabrics "Connect" command.
 367  *
 368  * Return:
 369  *      0: success
 370  *      > 0: NVMe error status code
 371  *      < 0: Linux errno error code
 372  *
 373  */
 374 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
 375 {
 376         struct nvme_command cmd;
 377         union nvme_result res;
 378         struct nvmf_connect_data *data;
 379         int ret;
 380
 381         memset(&cmd, 0, sizeof(cmd));
 382         cmd.connect.opcode = nvme_fabrics_command;
 383         cmd.connect.fctype = nvme_fabrics_type_connect;
 384         cmd.connect.qid = 0;
 385         cmd.connect.sqsize = cpu_to_le16(NVME_AQ_DEPTH - 1);
 386
 387         /*
 388          * Set keep-alive timeout in seconds granularity (ms * 1000)
 389          * and add a grace period for controller kato enforcement
 390          */
 391         cmd.connect.kato = ctrl->opts->discovery_nqn ? 0 :
 392                 cpu_to_le32((ctrl->kato + NVME_KATO_GRACE) * 1000);
 393
 394         data = kzalloc(sizeof(*data), GFP_KERNEL);
 395         if (!data)
 396                 return -ENOMEM;
 397
 398         uuid_copy(&data->hostid, &ctrl->opts->host->id);
 399         data->cntlid = cpu_to_le16(0xffff);
 400         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
 401         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
 402
 403         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res,
 404                         data, sizeof(*data), 0, NVME_QID_ANY, 1,
 405                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
 406         if (ret) {
 407                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(res.u32),
 408                                        &cmd, data);
 409                 goto out_free_data;
 410         }
 411
 412         ctrl->cntlid = le16_to_cpu(res.u16);
 413
 414 out_free_data:
 415         kfree(data);
 416         return ret;
 417 }
 418 EXPORT_SYMBOL_GPL(nvmf_connect_admin_queue);
 419
 420 /**
 421  * nvmf_connect_io_queue() - NVMe Fabrics I/O Queue "Connect"
 422  *                           API function.
 423  * @ctrl:       Host nvme controller instance used to establish an
 424  *              NVMe I/O queue connection to the already allocated NVMe
 425  *              controller on the target system.
 426  * @qid:        NVMe I/O queue number for the new I/O connection between
 427  *              host and target (note qid == 0 is illegal as this is
 428  *              the Admin queue, per NVMe standard).
 429  *
 430  * This function issues a fabrics-protocol connection
 431  * of a NVMe I/O queue (via NVMe Fabrics "Connect" command)
 432  * between the host system device and the allocated NVMe controller
 433  * on the target system.
 434  *
 435  * Return:
 436  *      0: success
 437  *      > 0: NVMe error status code
 438  *      < 0: Linux errno error code
 439  */
 440 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid)
 441 {
 442         struct nvme_command cmd;
 443         struct nvmf_connect_data *data;
 444         union nvme_result res;
 445         int ret;
 446
 447         memset(&cmd, 0, sizeof(cmd));
 448         cmd.connect.opcode = nvme_fabrics_command;
 449         cmd.connect.fctype = nvme_fabrics_type_connect;
 450         cmd.connect.qid = cpu_to_le16(qid);
 451         cmd.connect.sqsize = cpu_to_le16(ctrl->sqsize);
 452
 453         data = kzalloc(sizeof(*data), GFP_KERNEL);
 454         if (!data)
 455                 return -ENOMEM;
 456
 457         uuid_copy(&data->hostid, &ctrl->opts->host->id);
 458         data->cntlid = cpu_to_le16(ctrl->cntlid);
 459         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
 460         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
 461
 462         ret = __nvme_submit_sync_cmd(ctrl->connect_q, &cmd, &res,
 463                         data, sizeof(*data), 0, qid, 1,
 464                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
 465         if (ret) {
 466                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(res.u32),
 467                                        &cmd, data);
 468         }
 469         kfree(data);
 470         return ret;
 471 }
 472 EXPORT_SYMBOL_GPL(nvmf_connect_io_queue);
 473
 474 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl)
 475 {
 476         if (ctrl->opts->max_reconnects != -1 &&
 477             ctrl->nr_reconnects < ctrl->opts->max_reconnects)
 478                 return true;
 479
 480         return false;
 481 }
 482 EXPORT_SYMBOL_GPL(nvmf_should_reconnect);
 483
 484 /**
 485  * nvmf_register_transport() - NVMe Fabrics Library registration function.
 486  * @ops:        Transport ops instance to be registered to the
 487  *              common fabrics library.
 488  *
 489  * API function that registers the type of specific transport fabric
 490  * being implemented to the common NVMe fabrics library. Part of
 491  * the overall init sequence of starting up a fabrics driver.
 492  */
 493 int nvmf_register_transport(struct nvmf_transport_ops *ops)
 494 {
 495         if (!ops->create_ctrl)
 496                 return -EINVAL;
 497
 498         mutex_lock(&nvmf_transports_mutex);
 499         list_add_tail(&ops->entry, &nvmf_transports);
 500         mutex_unlock(&nvmf_transports_mutex);
 501
 502         return 0;
 503 }
 504 EXPORT_SYMBOL_GPL(nvmf_register_transport);
 505
 506 /**
 507  * nvmf_unregister_transport() - NVMe Fabrics Library unregistration function.
 508  * @ops:        Transport ops instance to be unregistered from the
 509  *              common fabrics library.
 510  *
 511  * Fabrics API function that unregisters the type of specific transport
 512  * fabric being implemented from the common NVMe fabrics library.
 513  * Part of the overall exit sequence of unloading the implemented driver.
 514  */
 515 void nvmf_unregister_transport(struct nvmf_transport_ops *ops)
 516 {
 517         mutex_lock(&nvmf_transports_mutex);
 518         list_del(&ops->entry);
 519         mutex_unlock(&nvmf_transports_mutex);
 520 }
 521 EXPORT_SYMBOL_GPL(nvmf_unregister_transport);
 522
 523 static struct nvmf_transport_ops *nvmf_lookup_transport(
 524                 struct nvmf_ctrl_options *opts)
 525 {
 526         struct nvmf_transport_ops *ops;
 527
 528         lockdep_assert_held(&nvmf_transports_mutex);
 529
 530         list_for_each_entry(ops, &nvmf_transports, entry) {
 531                 if (strcmp(ops->name, opts->transport) == 0)
 532                         return ops;
 533         }
 534
 535         return NULL;
 536 }
 537
 538 static const match_table_t opt_tokens = {
 539         { NVMF_OPT_TRANSPORT,           "transport=%s"          },
 540         { NVMF_OPT_TRADDR,              "traddr=%s"             },
 541         { NVMF_OPT_TRSVCID,             "trsvcid=%s"            },
 542         { NVMF_OPT_NQN,                 "nqn=%s"                },
 543         { NVMF_OPT_QUEUE_SIZE,          "queue_size=%d"         },
 544         { NVMF_OPT_NR_IO_QUEUES,        "nr_io_queues=%d"       },
 545         { NVMF_OPT_RECONNECT_DELAY,     "reconnect_delay=%d"    },
 546         { NVMF_OPT_CTRL_LOSS_TMO,       "ctrl_loss_tmo=%d"      },
 547         { NVMF_OPT_KATO,                "keep_alive_tmo=%d"     },
 548         { NVMF_OPT_HOSTNQN,             "hostnqn=%s"            },
 549         { NVMF_OPT_HOST_TRADDR,         "host_traddr=%s"        },
 550         { NVMF_OPT_HOST_ID,             "hostid=%s"             },
 551         { NVMF_OPT_ERR,                 NULL                    }
 552 };
 553
 554 static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
 555                 const char *buf)
 556 {
 557         substring_t args[MAX_OPT_ARGS];
 558         char *options, *o, *p;
 559         int token, ret = 0;
 560         size_t nqnlen  = 0;
 561         int ctrl_loss_tmo = NVMF_DEF_CTRL_LOSS_TMO;
 562         uuid_t hostid;
 563
 564         /* Set defaults */
 565         opts->queue_size = NVMF_DEF_QUEUE_SIZE;
 566         opts->nr_io_queues = num_online_cpus();
 567         opts->reconnect_delay = NVMF_DEF_RECONNECT_DELAY;
 568
 569         options = o = kstrdup(buf, GFP_KERNEL);
 570         if (!options)
 571                 return -ENOMEM;
 572
 573         uuid_gen(&hostid);
 574
 575         while ((p = strsep(&o, ",\n")) != NULL) {
 576                 if (!*p)
 577                         continue;
 578
 579                 token = match_token(p, opt_tokens, args);
 580                 opts->mask |= token;
 581                 switch (token) {
 582                 case NVMF_OPT_TRANSPORT:
 583                         p = match_strdup(args);
 584                         if (!p) {
 585                                 ret = -ENOMEM;
 586                                 goto out;
 587                         }
 588                         opts->transport = p;
 589                         break;
 590                 case NVMF_OPT_NQN:
 591                         p = match_strdup(args);
 592                         if (!p) {
 593                                 ret = -ENOMEM;
 594                                 goto out;
 595                         }
 596                         opts->subsysnqn = p;
 597                         nqnlen = strlen(opts->subsysnqn);
 598                         if (nqnlen >= NVMF_NQN_SIZE) {
 599                                 pr_err("%s needs to be < %d bytes\n",
 600                                         opts->subsysnqn, NVMF_NQN_SIZE);
 601                                 ret = -EINVAL;
 602                                 goto out;
 603                         }
 604                         opts->discovery_nqn =
 605                                 !(strcmp(opts->subsysnqn,
 606                                          NVME_DISC_SUBSYS_NAME));
 607                         if (opts->discovery_nqn)
 608                                 opts->nr_io_queues = 0;
 609                         break;
 610                 case NVMF_OPT_TRADDR:
 611                         p = match_strdup(args);
 612                         if (!p) {
 613                                 ret = -ENOMEM;
 614                                 goto out;
 615                         }
 616                         opts->traddr = p;
 617                         break;
 618                 case NVMF_OPT_TRSVCID:
 619                         p = match_strdup(args);
 620                         if (!p) {
 621                                 ret = -ENOMEM;
 622                                 goto out;
 623                         }
 624                         opts->trsvcid = p;
 625                         break;
 626                 case NVMF_OPT_QUEUE_SIZE:
 627                         if (match_int(args, &token)) {
 628                                 ret = -EINVAL;
 629                                 goto out;
 630                         }
 631                         if (token < NVMF_MIN_QUEUE_SIZE ||
 632                             token > NVMF_MAX_QUEUE_SIZE) {
 633                                 pr_err("Invalid queue_size %d\n", token);
 634                                 ret = -EINVAL;
 635                                 goto out;
 636                         }
 637                         opts->queue_size = token;
 638                         break;
 639                 case NVMF_OPT_NR_IO_QUEUES:
 640                         if (match_int(args, &token)) {
 641                                 ret = -EINVAL;
 642                                 goto out;
 643                         }
 644                         if (token <= 0) {
 645                                 pr_err("Invalid number of IOQs %d\n", token);
 646                                 ret = -EINVAL;
 647                                 goto out;
 648                         }
 649                         opts->nr_io_queues = min_t(unsigned int,
 650                                         num_online_cpus(), token);
 651                         break;
 652                 case NVMF_OPT_KATO:
 653                         if (match_int(args, &token)) {
 654                                 ret = -EINVAL;
 655                                 goto out;
 656                         }
 657
 658                         if (opts->discovery_nqn) {
 659                                 pr_err("Discovery controllers cannot accept keep_alive_tmo != 0\n");
 660                                 ret = -EINVAL;
 661                                 goto out;
 662                         }
 663
 664                         if (token < 0) {
 665                                 pr_err("Invalid keep_alive_tmo %d\n", token);
 666                                 ret = -EINVAL;
 667                                 goto out;
 668                         } else if (token == 0) {
 669                                 /* Allowed for debug */
 670                                 pr_warn("keep_alive_tmo 0 won't execute keep alives!!!\n");
 671                         }
 672                         opts->kato = token;
 673                         break;
 674                 case NVMF_OPT_CTRL_LOSS_TMO:
 675                         if (match_int(args, &token)) {
 676                                 ret = -EINVAL;
 677                                 goto out;
 678                         }
 679
 680                         if (token < 0)
 681                                 pr_warn("ctrl_loss_tmo < 0 will reconnect forever\n");
 682                         ctrl_loss_tmo = token;
 683                         break;
 684                 case NVMF_OPT_HOSTNQN:
 685                         if (opts->host) {
 686                                 pr_err("hostnqn already user-assigned: %s\n",
 687                                        opts->host->nqn);
 688                                 ret = -EADDRINUSE;
 689                                 goto out;
 690                         }
 691                         p = match_strdup(args);
 692                         if (!p) {
 693                                 ret = -ENOMEM;
 694                                 goto out;
 695                         }
 696                         nqnlen = strlen(p);
 697                         if (nqnlen >= NVMF_NQN_SIZE) {
 698                                 pr_err("%s needs to be < %d bytes\n",
 699                                         p, NVMF_NQN_SIZE);
 700                                 kfree(p);
 701                                 ret = -EINVAL;
 702                                 goto out;
 703                         }
 704                         opts->host = nvmf_host_add(p);
 705                         kfree(p);
 706                         if (!opts->host) {
 707                                 ret = -ENOMEM;
 708                                 goto out;
 709                         }
 710                         break;
 711                 case NVMF_OPT_RECONNECT_DELAY:
 712                         if (match_int(args, &token)) {
 713                                 ret = -EINVAL;
 714                                 goto out;
 715                         }
 716                         if (token <= 0) {
 717                                 pr_err("Invalid reconnect_delay %d\n", token);
 718                                 ret = -EINVAL;
 719                                 goto out;
 720                         }
 721                         opts->reconnect_delay = token;
 722                         break;
 723                 case NVMF_OPT_HOST_TRADDR:
 724                         p = match_strdup(args);
 725                         if (!p) {
 726                                 ret = -ENOMEM;
 727                                 goto out;
 728                         }
 729                         opts->host_traddr = p;
 730                         break;
 731                 case NVMF_OPT_HOST_ID:
 732                         p = match_strdup(args);
 733                         if (!p) {
 734                                 ret = -ENOMEM;
 735                                 goto out;
 736                         }
 737                         if (uuid_parse(p, &hostid)) {
 738                                 ret = -EINVAL;
 739                                 goto out;
 740                         }
 741                         break;
 742                 default:
 743                         pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
 744                                 p);
 745                         ret = -EINVAL;
 746                         goto out;
 747                 }
 748         }
 749
 750         if (ctrl_loss_tmo < 0)
 751                 opts->max_reconnects = -1;
 752         else
 753                 opts->max_reconnects = DIV_ROUND_UP(ctrl_loss_tmo,
 754                                                 opts->reconnect_delay);
 755
 756         if (!opts->host) {
 757                 kref_get(&nvmf_default_host->ref);
 758                 opts->host = nvmf_default_host;
 759         }
 760
 761         uuid_copy(&opts->host->id, &hostid);
 762
 763 out:
 764         if (!opts->discovery_nqn && !opts->kato)
 765                 opts->kato = NVME_DEFAULT_KATO;
 766         kfree(options);
 767         return ret;
 768 }
 769
 770 static int nvmf_check_required_opts(struct nvmf_ctrl_options *opts,
 771                 unsigned int required_opts)
 772 {
 773         if ((opts->mask & required_opts) != required_opts) {
 774                 int i;
 775
 776                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
 777                         if ((opt_tokens[i].token & required_opts) &&
 778                             !(opt_tokens[i].token & opts->mask)) {
 779                                 pr_warn("missing parameter '%s'\n",
 780                                         opt_tokens[i].pattern);
 781                         }
 782                 }
 783
 784                 return -EINVAL;
 785         }
 786
 787         return 0;
 788 }
 789
 790 static int nvmf_check_allowed_opts(struct nvmf_ctrl_options *opts,
 791                 unsigned int allowed_opts)
 792 {
 793         if (opts->mask & ~allowed_opts) {
 794                 int i;
 795
 796                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
 797                         if ((opt_tokens[i].token & opts->mask) &&
 798                             (opt_tokens[i].token & ~allowed_opts)) {
 799                                 pr_warn("invalid parameter '%s'\n",
 800                                         opt_tokens[i].pattern);
 801                         }
 802                 }
 803
 804                 return -EINVAL;
 805         }
 806
 807         return 0;
 808 }
 809
 810 void nvmf_free_options(struct nvmf_ctrl_options *opts)
 811 {
 812         nvmf_host_put(opts->host);
 813         kfree(opts->transport);
 814         kfree(opts->traddr);
 815         kfree(opts->trsvcid);
 816         kfree(opts->subsysnqn);
 817         kfree(opts->host_traddr);
 818         kfree(opts);
 819 }
 820 EXPORT_SYMBOL_GPL(nvmf_free_options);
 821
 822 #define NVMF_REQUIRED_OPTS      (NVMF_OPT_TRANSPORT | NVMF_OPT_NQN)
 823 #define NVMF_ALLOWED_OPTS       (NVMF_OPT_QUEUE_SIZE | NVMF_OPT_NR_IO_QUEUES | \
 824                                  NVMF_OPT_KATO | NVMF_OPT_HOSTNQN | \
 825                                  NVMF_OPT_HOST_ID)
 826
 827 static struct nvme_ctrl *
 828 nvmf_create_ctrl(struct device *dev, const char *buf, size_t count)
 829 {
 830         struct nvmf_ctrl_options *opts;
 831         struct nvmf_transport_ops *ops;
 832         struct nvme_ctrl *ctrl;
 833         int ret;
 834
 835         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 836         if (!opts)
 837                 return ERR_PTR(-ENOMEM);
 838
 839         ret = nvmf_parse_options(opts, buf);
 840         if (ret)
 841                 goto out_free_opts;
 842
 843         /*
 844          * Check the generic options first as we need a valid transport for
 845          * the lookup below.  Then clear the generic flags so that transport
 846          * drivers don't have to care about them.
 847          */
 848         ret = nvmf_check_required_opts(opts, NVMF_REQUIRED_OPTS);
 849         if (ret)
 850                 goto out_free_opts;
 851         opts->mask &= ~NVMF_REQUIRED_OPTS;
 852
 853         mutex_lock(&nvmf_transports_mutex);
 854         ops = nvmf_lookup_transport(opts);
 855         if (!ops) {
 856                 pr_info("no handler found for transport %s.\n",
 857                         opts->transport);
 858                 ret = -EINVAL;
 859                 goto out_unlock;
 860         }
 861
 862         ret = nvmf_check_required_opts(opts, ops->required_opts);
 863         if (ret)
 864                 goto out_unlock;
 865         ret = nvmf_check_allowed_opts(opts, NVMF_ALLOWED_OPTS |
 866                                 ops->allowed_opts | ops->required_opts);
 867         if (ret)
 868                 goto out_unlock;
 869
 870         ctrl = ops->create_ctrl(dev, opts);
 871         if (IS_ERR(ctrl)) {
 872                 ret = PTR_ERR(ctrl);
 873                 goto out_unlock;
 874         }
 875
 876         if (strcmp(ctrl->subnqn, opts->subsysnqn)) {
 877                 dev_warn(ctrl->device,
 878                         "controller returned incorrect NQN: \"%s\".\n",
 879                         ctrl->subnqn);
 880                 mutex_unlock(&nvmf_transports_mutex);
 881                 ctrl->ops->delete_ctrl(ctrl);
 882                 return ERR_PTR(-EINVAL);
 883         }
 884
 885         mutex_unlock(&nvmf_transports_mutex);
 886         return ctrl;
 887
 888 out_unlock:
 889         mutex_unlock(&nvmf_transports_mutex);
 890 out_free_opts:
 891         nvmf_free_options(opts);
 892         return ERR_PTR(ret);
 893 }
 894
 895 static struct class *nvmf_class;
 896 static struct device *nvmf_device;
 897 static DEFINE_MUTEX(nvmf_dev_mutex);
 898
 899 static ssize_t nvmf_dev_write(struct file *file, const char __user *ubuf,
 900                 size_t count, loff_t *pos)
 901 {
 902         struct seq_file *seq_file = file->private_data;
 903         struct nvme_ctrl *ctrl;
 904         const char *buf;
 905         int ret = 0;
 906
 907         if (count > PAGE_SIZE)
 908                 return -ENOMEM;
 909
 910         buf = memdup_user_nul(ubuf, count);
 911         if (IS_ERR(buf))
 912                 return PTR_ERR(buf);
 913
 914         mutex_lock(&nvmf_dev_mutex);
 915         if (seq_file->private) {
 916                 ret = -EINVAL;
 917                 goto out_unlock;
 918         }
 919
 920         ctrl = nvmf_create_ctrl(nvmf_device, buf, count);
 921         if (IS_ERR(ctrl)) {
 922                 ret = PTR_ERR(ctrl);
 923                 goto out_unlock;
 924         }
 925
 926         seq_file->private = ctrl;
 927
 928 out_unlock:
 929         mutex_unlock(&nvmf_dev_mutex);
 930         kfree(buf);
 931         return ret ? ret : count;
 932 }
 933
 934 static int nvmf_dev_show(struct seq_file *seq_file, void *private)
 935 {
 936         struct nvme_ctrl *ctrl;
 937         int ret = 0;
 938
 939         mutex_lock(&nvmf_dev_mutex);
 940         ctrl = seq_file->private;
 941         if (!ctrl) {
 942                 ret = -EINVAL;
 943                 goto out_unlock;
 944         }
 945
 946         seq_printf(seq_file, "instance=%d,cntlid=%d\n",
 947                         ctrl->instance, ctrl->cntlid);
 948
 949 out_unlock:
 950         mutex_unlock(&nvmf_dev_mutex);
 951         return ret;
 952 }
 953
 954 static int nvmf_dev_open(struct inode *inode, struct file *file)
 955 {
 956         /*
 957          * The miscdevice code initializes file->private_data, but doesn't
 958          * make use of it later.
 959          */
 960         file->private_data = NULL;
 961         return single_open(file, nvmf_dev_show, NULL);
 962 }
 963
 964 static int nvmf_dev_release(struct inode *inode, struct file *file)
 965 {
 966         struct seq_file *seq_file = file->private_data;
 967         struct nvme_ctrl *ctrl = seq_file->private;
 968
 969         if (ctrl)
 970                 nvme_put_ctrl(ctrl);
 971         return single_release(inode, file);
 972 }
 973
 974 static const struct file_operations nvmf_dev_fops = {
 975         .owner          = THIS_MODULE,
 976         .write          = nvmf_dev_write,
 977         .read           = seq_read,
 978         .open           = nvmf_dev_open,
 979         .release        = nvmf_dev_release,
 980 };
 981
 982 static struct miscdevice nvmf_misc = {
 983         .minor          = MISC_DYNAMIC_MINOR,
 984         .name           = "nvme-fabrics",
 985         .fops           = &nvmf_dev_fops,
 986 };
 987
 988 static int __init nvmf_init(void)
 989 {
 990         int ret;
 991
 992         nvmf_default_host = nvmf_host_default();
 993         if (!nvmf_default_host)
 994                 return -ENOMEM;
 995
 996         nvmf_class = class_create(THIS_MODULE, "nvme-fabrics");
 997         if (IS_ERR(nvmf_class)) {
 998                 pr_err("couldn't register class nvme-fabrics\n");
 999                 ret = PTR_ERR(nvmf_class);
1000                 goto out_free_host;
1001         }
1002
1003         nvmf_device =
1004                 device_create(nvmf_class, NULL, MKDEV(0, 0), NULL, "ctl");
1005         if (IS_ERR(nvmf_device)) {
1006                 pr_err("couldn't create nvme-fabris device!\n");
1007                 ret = PTR_ERR(nvmf_device);
1008                 goto out_destroy_class;
1009         }
1010
1011         ret = misc_register(&nvmf_misc);
1012         if (ret) {
1013                 pr_err("couldn't register misc device: %d\n", ret);
1014                 goto out_destroy_device;
1015         }
1016
1017         return 0;
1018
1019 out_destroy_device:
1020         device_destroy(nvmf_class, MKDEV(0, 0));
1021 out_destroy_class:
1022         class_destroy(nvmf_class);
1023 out_free_host:
1024         nvmf_host_put(nvmf_default_host);
1025         return ret;
1026 }
1027
1028 static void __exit nvmf_exit(void)
1029 {
1030         misc_deregister(&nvmf_misc);
1031         device_destroy(nvmf_class, MKDEV(0, 0));
1032         class_destroy(nvmf_class);
1033         nvmf_host_put(nvmf_default_host);
1034
1035         BUILD_BUG_ON(sizeof(struct nvmf_connect_command) != 64);
1036         BUILD_BUG_ON(sizeof(struct nvmf_property_get_command) != 64);
1037         BUILD_BUG_ON(sizeof(struct nvmf_property_set_command) != 64);
1038         BUILD_BUG_ON(sizeof(struct nvmf_connect_data) != 1024);
1039 }
1040
1041 MODULE_LICENSE("GPL v2");
1042
1043 module_init(nvmf_init);
1044 module_exit(nvmf_exit);