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         int len = 0;
 115
 116         if (ctrl->opts->mask & NVMF_OPT_TRADDR)
 117                 len += snprintf(buf, size, "traddr=%s", ctrl->opts->traddr);
 118         if (ctrl->opts->mask & NVMF_OPT_TRSVCID)
 119                 len += snprintf(buf + len, size - len, "%strsvcid=%s",
 120                                 (len) ? "," : "", ctrl->opts->trsvcid);
 121         if (ctrl->opts->mask & NVMF_OPT_HOST_TRADDR)
 122                 len += snprintf(buf + len, size - len, "%shost_traddr=%s",
 123                                 (len) ? "," : "", ctrl->opts->host_traddr);
 124         len += snprintf(buf + len, size - len, "\n");
 125
 126         return len;
 127 }
 128 EXPORT_SYMBOL_GPL(nvmf_get_address);
 129
 130 /**
 131  * nvmf_get_subsysnqn() - Get subsystem NQN
 132  * @ctrl:       Host NVMe controller instance which we got the NQN
 133  */
 134 const char *nvmf_get_subsysnqn(struct nvme_ctrl *ctrl)
 135 {
 136         return ctrl->opts->subsysnqn;
 137 }
 138 EXPORT_SYMBOL_GPL(nvmf_get_subsysnqn);
 139
 140 /**
 141  * nvmf_reg_read32() -  NVMe Fabrics "Property Get" API function.
 142  * @ctrl:       Host NVMe controller instance maintaining the admin
 143  *              queue used to submit the property read command to
 144  *              the allocated NVMe controller resource on the target system.
 145  * @off:        Starting offset value of the targeted property
 146  *              register (see the fabrics section of the NVMe standard).
 147  * @val:        OUTPUT parameter that will contain the value of
 148  *              the property after a successful read.
 149  *
 150  * Used by the host system to retrieve a 32-bit capsule property value
 151  * from an NVMe controller on the target system.
 152  *
 153  * ("Capsule property" is an "PCIe register concept" applied to the
 154  * NVMe fabrics space.)
 155  *
 156  * Return:
 157  *      0: successful read
 158  *      > 0: NVMe error status code
 159  *      < 0: Linux errno error code
 160  */
 161 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
 162 {
 163         struct nvme_command cmd;
 164         union nvme_result res;
 165         int ret;
 166
 167         memset(&cmd, 0, sizeof(cmd));
 168         cmd.prop_get.opcode = nvme_fabrics_command;
 169         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
 170         cmd.prop_get.offset = cpu_to_le32(off);
 171
 172         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res, NULL, 0, 0,
 173                         NVME_QID_ANY, 0, 0);
 174
 175         if (ret >= 0)
 176                 *val = le64_to_cpu(res.u64);
 177         if (unlikely(ret != 0))
 178                 dev_err(ctrl->device,
 179                         "Property Get error: %d, offset %#x\n",
 180                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 181
 182         return ret;
 183 }
 184 EXPORT_SYMBOL_GPL(nvmf_reg_read32);
 185
 186 /**
 187  * nvmf_reg_read64() -  NVMe Fabrics "Property Get" API function.
 188  * @ctrl:       Host NVMe controller instance maintaining the admin
 189  *              queue used to submit the property read command to
 190  *              the allocated controller resource on the target system.
 191  * @off:        Starting offset value of the targeted property
 192  *              register (see the fabrics section of the NVMe standard).
 193  * @val:        OUTPUT parameter that will contain the value of
 194  *              the property after a successful read.
 195  *
 196  * Used by the host system to retrieve a 64-bit capsule property value
 197  * from an NVMe controller on the target system.
 198  *
 199  * ("Capsule property" is an "PCIe register concept" applied to the
 200  * NVMe fabrics space.)
 201  *
 202  * Return:
 203  *      0: successful read
 204  *      > 0: NVMe error status code
 205  *      < 0: Linux errno error code
 206  */
 207 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
 208 {
 209         struct nvme_command cmd;
 210         union nvme_result res;
 211         int ret;
 212
 213         memset(&cmd, 0, sizeof(cmd));
 214         cmd.prop_get.opcode = nvme_fabrics_command;
 215         cmd.prop_get.fctype = nvme_fabrics_type_property_get;
 216         cmd.prop_get.attrib = 1;
 217         cmd.prop_get.offset = cpu_to_le32(off);
 218
 219         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res, NULL, 0, 0,
 220                         NVME_QID_ANY, 0, 0);
 221
 222         if (ret >= 0)
 223                 *val = le64_to_cpu(res.u64);
 224         if (unlikely(ret != 0))
 225                 dev_err(ctrl->device,
 226                         "Property Get error: %d, offset %#x\n",
 227                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 228         return ret;
 229 }
 230 EXPORT_SYMBOL_GPL(nvmf_reg_read64);
 231
 232 /**
 233  * nvmf_reg_write32() -  NVMe Fabrics "Property Write" API function.
 234  * @ctrl:       Host NVMe controller instance maintaining the admin
 235  *              queue used to submit the property read command to
 236  *              the allocated NVMe controller resource on the target system.
 237  * @off:        Starting offset value of the targeted property
 238  *              register (see the fabrics section of the NVMe standard).
 239  * @val:        Input parameter that contains the value to be
 240  *              written to the property.
 241  *
 242  * Used by the NVMe host system to write a 32-bit capsule property value
 243  * to an NVMe controller on the target system.
 244  *
 245  * ("Capsule property" is an "PCIe register concept" applied to the
 246  * NVMe fabrics space.)
 247  *
 248  * Return:
 249  *      0: successful write
 250  *      > 0: NVMe error status code
 251  *      < 0: Linux errno error code
 252  */
 253 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
 254 {
 255         struct nvme_command cmd;
 256         int ret;
 257
 258         memset(&cmd, 0, sizeof(cmd));
 259         cmd.prop_set.opcode = nvme_fabrics_command;
 260         cmd.prop_set.fctype = nvme_fabrics_type_property_set;
 261         cmd.prop_set.attrib = 0;
 262         cmd.prop_set.offset = cpu_to_le32(off);
 263         cmd.prop_set.value = cpu_to_le64(val);
 264
 265         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, NULL, NULL, 0, 0,
 266                         NVME_QID_ANY, 0, 0);
 267         if (unlikely(ret))
 268                 dev_err(ctrl->device,
 269                         "Property Set error: %d, offset %#x\n",
 270                         ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
 271         return ret;
 272 }
 273 EXPORT_SYMBOL_GPL(nvmf_reg_write32);
 274
 275 /**
 276  * nvmf_log_connect_error() - Error-parsing-diagnostic print
 277  * out function for connect() errors.
 278  *
 279  * @ctrl: the specific /dev/nvmeX device that had the error.
 280  *
 281  * @errval: Error code to be decoded in a more human-friendly
 282  *          printout.
 283  *
 284  * @offset: For use with the NVMe error code NVME_SC_CONNECT_INVALID_PARAM.
 285  *
 286  * @cmd: This is the SQE portion of a submission capsule.
 287  *
 288  * @data: This is the "Data" portion of a submission capsule.
 289  */
 290 static void nvmf_log_connect_error(struct nvme_ctrl *ctrl,
 291                 int errval, int offset, struct nvme_command *cmd,
 292                 struct nvmf_connect_data *data)
 293 {
 294         int err_sctype = errval & (~NVME_SC_DNR);
 295
 296         switch (err_sctype) {
 297
 298         case (NVME_SC_CONNECT_INVALID_PARAM):
 299                 if (offset >> 16) {
 300                         char *inv_data = "Connect Invalid Data Parameter";
 301
 302                         switch (offset & 0xffff) {
 303                         case (offsetof(struct nvmf_connect_data, cntlid)):
 304                                 dev_err(ctrl->device,
 305                                         "%s, cntlid: %d\n",
 306                                         inv_data, data->cntlid);
 307                                 break;
 308                         case (offsetof(struct nvmf_connect_data, hostnqn)):
 309                                 dev_err(ctrl->device,
 310                                         "%s, hostnqn \"%s\"\n",
 311                                         inv_data, data->hostnqn);
 312                                 break;
 313                         case (offsetof(struct nvmf_connect_data, subsysnqn)):
 314                                 dev_err(ctrl->device,
 315                                         "%s, subsysnqn \"%s\"\n",
 316                                         inv_data, data->subsysnqn);
 317                                 break;
 318                         default:
 319                                 dev_err(ctrl->device,
 320                                         "%s, starting byte offset: %d\n",
 321                                        inv_data, offset & 0xffff);
 322                                 break;
 323                         }
 324                 } else {
 325                         char *inv_sqe = "Connect Invalid SQE Parameter";
 326
 327                         switch (offset) {
 328                         case (offsetof(struct nvmf_connect_command, qid)):
 329                                 dev_err(ctrl->device,
 330                                        "%s, qid %d\n",
 331                                         inv_sqe, cmd->connect.qid);
 332                                 break;
 333                         default:
 334                                 dev_err(ctrl->device,
 335                                         "%s, starting byte offset: %d\n",
 336                                         inv_sqe, offset);
 337                         }
 338                 }
 339                 break;
 340         default:
 341                 dev_err(ctrl->device,
 342                         "Connect command failed, error wo/DNR bit: %d\n",
 343                         err_sctype);
 344                 break;
 345         } /* switch (err_sctype) */
 346 }
 347
 348 /**
 349  * nvmf_connect_admin_queue() - NVMe Fabrics Admin Queue "Connect"
 350  *                              API function.
 351  * @ctrl:       Host nvme controller instance used to request
 352  *              a new NVMe controller allocation on the target
 353  *              system and  establish an NVMe Admin connection to
 354  *              that controller.
 355  *
 356  * This function enables an NVMe host device to request a new allocation of
 357  * an NVMe controller resource on a target system as well establish a
 358  * fabrics-protocol connection of the NVMe Admin queue between the
 359  * host system device and the allocated NVMe controller on the
 360  * target system via a NVMe Fabrics "Connect" command.
 361  *
 362  * Return:
 363  *      0: success
 364  *      > 0: NVMe error status code
 365  *      < 0: Linux errno error code
 366  *
 367  */
 368 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
 369 {
 370         struct nvme_command cmd;
 371         union nvme_result res;
 372         struct nvmf_connect_data *data;
 373         int ret;
 374
 375         memset(&cmd, 0, sizeof(cmd));
 376         cmd.connect.opcode = nvme_fabrics_command;
 377         cmd.connect.fctype = nvme_fabrics_type_connect;
 378         cmd.connect.qid = 0;
 379
 380         /*
 381          * fabrics spec sets a minimum of depth 32 for admin queue,
 382          * so set the queue with this depth always until
 383          * justification otherwise.
 384          */
 385         cmd.connect.sqsize = cpu_to_le16(NVMF_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         memcpy(&data->hostid, &ctrl->opts->host->id, sizeof(uuid_be));
 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         memcpy(&data->hostid, &ctrl->opts->host->id, sizeof(uuid_be));
 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->opts->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_ERR,                 NULL                    }
 551 };
 552
 553 static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
 554                 const char *buf)
 555 {
 556         substring_t args[MAX_OPT_ARGS];
 557         char *options, *o, *p;
 558         int token, ret = 0;
 559         size_t nqnlen  = 0;
 560         int ctrl_loss_tmo = NVMF_DEF_CTRL_LOSS_TMO;
 561
 562         /* Set defaults */
 563         opts->queue_size = NVMF_DEF_QUEUE_SIZE;
 564         opts->nr_io_queues = num_online_cpus();
 565         opts->reconnect_delay = NVMF_DEF_RECONNECT_DELAY;
 566
 567         options = o = kstrdup(buf, GFP_KERNEL);
 568         if (!options)
 569                 return -ENOMEM;
 570
 571         while ((p = strsep(&o, ",\n")) != NULL) {
 572                 if (!*p)
 573                         continue;
 574
 575                 token = match_token(p, opt_tokens, args);
 576                 opts->mask |= token;
 577                 switch (token) {
 578                 case NVMF_OPT_TRANSPORT:
 579                         p = match_strdup(args);
 580                         if (!p) {
 581                                 ret = -ENOMEM;
 582                                 goto out;
 583                         }
 584                         opts->transport = p;
 585                         break;
 586                 case NVMF_OPT_NQN:
 587                         p = match_strdup(args);
 588                         if (!p) {
 589                                 ret = -ENOMEM;
 590                                 goto out;
 591                         }
 592                         opts->subsysnqn = p;
 593                         nqnlen = strlen(opts->subsysnqn);
 594                         if (nqnlen >= NVMF_NQN_SIZE) {
 595                                 pr_err("%s needs to be < %d bytes\n",
 596                                         opts->subsysnqn, NVMF_NQN_SIZE);
 597                                 ret = -EINVAL;
 598                                 goto out;
 599                         }
 600                         opts->discovery_nqn =
 601                                 !(strcmp(opts->subsysnqn,
 602                                          NVME_DISC_SUBSYS_NAME));
 603                         if (opts->discovery_nqn)
 604                                 opts->nr_io_queues = 0;
 605                         break;
 606                 case NVMF_OPT_TRADDR:
 607                         p = match_strdup(args);
 608                         if (!p) {
 609                                 ret = -ENOMEM;
 610                                 goto out;
 611                         }
 612                         opts->traddr = p;
 613                         break;
 614                 case NVMF_OPT_TRSVCID:
 615                         p = match_strdup(args);
 616                         if (!p) {
 617                                 ret = -ENOMEM;
 618                                 goto out;
 619                         }
 620                         opts->trsvcid = p;
 621                         break;
 622                 case NVMF_OPT_QUEUE_SIZE:
 623                         if (match_int(args, &token)) {
 624                                 ret = -EINVAL;
 625                                 goto out;
 626                         }
 627                         if (token < NVMF_MIN_QUEUE_SIZE ||
 628                             token > NVMF_MAX_QUEUE_SIZE) {
 629                                 pr_err("Invalid queue_size %d\n", token);
 630                                 ret = -EINVAL;
 631                                 goto out;
 632                         }
 633                         opts->queue_size = token;
 634                         break;
 635                 case NVMF_OPT_NR_IO_QUEUES:
 636                         if (match_int(args, &token)) {
 637                                 ret = -EINVAL;
 638                                 goto out;
 639                         }
 640                         if (token <= 0) {
 641                                 pr_err("Invalid number of IOQs %d\n", token);
 642                                 ret = -EINVAL;
 643                                 goto out;
 644                         }
 645                         opts->nr_io_queues = min_t(unsigned int,
 646                                         num_online_cpus(), token);
 647                         break;
 648                 case NVMF_OPT_KATO:
 649                         if (match_int(args, &token)) {
 650                                 ret = -EINVAL;
 651                                 goto out;
 652                         }
 653
 654                         if (opts->discovery_nqn) {
 655                                 pr_err("Discovery controllers cannot accept keep_alive_tmo != 0\n");
 656                                 ret = -EINVAL;
 657                                 goto out;
 658                         }
 659
 660                         if (token < 0) {
 661                                 pr_err("Invalid keep_alive_tmo %d\n", token);
 662                                 ret = -EINVAL;
 663                                 goto out;
 664                         } else if (token == 0) {
 665                                 /* Allowed for debug */
 666                                 pr_warn("keep_alive_tmo 0 won't execute keep alives!!!\n");
 667                         }
 668                         opts->kato = token;
 669                         break;
 670                 case NVMF_OPT_CTRL_LOSS_TMO:
 671                         if (match_int(args, &token)) {
 672                                 ret = -EINVAL;
 673                                 goto out;
 674                         }
 675
 676                         if (token < 0)
 677                                 pr_warn("ctrl_loss_tmo < 0 will reconnect forever\n");
 678                         ctrl_loss_tmo = token;
 679                         break;
 680                 case NVMF_OPT_HOSTNQN:
 681                         if (opts->host) {
 682                                 pr_err("hostnqn already user-assigned: %s\n",
 683                                        opts->host->nqn);
 684                                 ret = -EADDRINUSE;
 685                                 goto out;
 686                         }
 687                         p = match_strdup(args);
 688                         if (!p) {
 689                                 ret = -ENOMEM;
 690                                 goto out;
 691                         }
 692                         nqnlen = strlen(p);
 693                         if (nqnlen >= NVMF_NQN_SIZE) {
 694                                 pr_err("%s needs to be < %d bytes\n",
 695                                         p, NVMF_NQN_SIZE);
 696                                 kfree(p);
 697                                 ret = -EINVAL;
 698                                 goto out;
 699                         }
 700                         opts->host = nvmf_host_add(p);
 701                         kfree(p);
 702                         if (!opts->host) {
 703                                 ret = -ENOMEM;
 704                                 goto out;
 705                         }
 706                         break;
 707                 case NVMF_OPT_RECONNECT_DELAY:
 708                         if (match_int(args, &token)) {
 709                                 ret = -EINVAL;
 710                                 goto out;
 711                         }
 712                         if (token <= 0) {
 713                                 pr_err("Invalid reconnect_delay %d\n", token);
 714                                 ret = -EINVAL;
 715                                 goto out;
 716                         }
 717                         opts->reconnect_delay = token;
 718                         break;
 719                 case NVMF_OPT_HOST_TRADDR:
 720                         p = match_strdup(args);
 721                         if (!p) {
 722                                 ret = -ENOMEM;
 723                                 goto out;
 724                         }
 725                         opts->host_traddr = p;
 726                         break;
 727                 default:
 728                         pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
 729                                 p);
 730                         ret = -EINVAL;
 731                         goto out;
 732                 }
 733         }
 734
 735         if (ctrl_loss_tmo < 0)
 736                 opts->max_reconnects = -1;
 737         else
 738                 opts->max_reconnects = DIV_ROUND_UP(ctrl_loss_tmo,
 739                                                 opts->reconnect_delay);
 740
 741         if (!opts->host) {
 742                 kref_get(&nvmf_default_host->ref);
 743                 opts->host = nvmf_default_host;
 744         }
 745
 746 out:
 747         if (!opts->discovery_nqn && !opts->kato)
 748                 opts->kato = NVME_DEFAULT_KATO;
 749         kfree(options);
 750         return ret;
 751 }
 752
 753 static int nvmf_check_required_opts(struct nvmf_ctrl_options *opts,
 754                 unsigned int required_opts)
 755 {
 756         if ((opts->mask & required_opts) != required_opts) {
 757                 int i;
 758
 759                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
 760                         if ((opt_tokens[i].token & required_opts) &&
 761                             !(opt_tokens[i].token & opts->mask)) {
 762                                 pr_warn("missing parameter '%s'\n",
 763                                         opt_tokens[i].pattern);
 764                         }
 765                 }
 766
 767                 return -EINVAL;
 768         }
 769
 770         return 0;
 771 }
 772
 773 static int nvmf_check_allowed_opts(struct nvmf_ctrl_options *opts,
 774                 unsigned int allowed_opts)
 775 {
 776         if (opts->mask & ~allowed_opts) {
 777                 int i;
 778
 779                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
 780                         if (opt_tokens[i].token & ~allowed_opts) {
 781                                 pr_warn("invalid parameter '%s'\n",
 782                                         opt_tokens[i].pattern);
 783                         }
 784                 }
 785
 786                 return -EINVAL;
 787         }
 788
 789         return 0;
 790 }
 791
 792 void nvmf_free_options(struct nvmf_ctrl_options *opts)
 793 {
 794         nvmf_host_put(opts->host);
 795         kfree(opts->transport);
 796         kfree(opts->traddr);
 797         kfree(opts->trsvcid);
 798         kfree(opts->subsysnqn);
 799         kfree(opts->host_traddr);
 800         kfree(opts);
 801 }
 802 EXPORT_SYMBOL_GPL(nvmf_free_options);
 803
 804 #define NVMF_REQUIRED_OPTS      (NVMF_OPT_TRANSPORT | NVMF_OPT_NQN)
 805 #define NVMF_ALLOWED_OPTS       (NVMF_OPT_QUEUE_SIZE | NVMF_OPT_NR_IO_QUEUES | \
 806                                  NVMF_OPT_KATO | NVMF_OPT_HOSTNQN)
 807
 808 static struct nvme_ctrl *
 809 nvmf_create_ctrl(struct device *dev, const char *buf, size_t count)
 810 {
 811         struct nvmf_ctrl_options *opts;
 812         struct nvmf_transport_ops *ops;
 813         struct nvme_ctrl *ctrl;
 814         int ret;
 815
 816         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 817         if (!opts)
 818                 return ERR_PTR(-ENOMEM);
 819
 820         ret = nvmf_parse_options(opts, buf);
 821         if (ret)
 822                 goto out_free_opts;
 823
 824         /*
 825          * Check the generic options first as we need a valid transport for
 826          * the lookup below.  Then clear the generic flags so that transport
 827          * drivers don't have to care about them.
 828          */
 829         ret = nvmf_check_required_opts(opts, NVMF_REQUIRED_OPTS);
 830         if (ret)
 831                 goto out_free_opts;
 832         opts->mask &= ~NVMF_REQUIRED_OPTS;
 833
 834         mutex_lock(&nvmf_transports_mutex);
 835         ops = nvmf_lookup_transport(opts);
 836         if (!ops) {
 837                 pr_info("no handler found for transport %s.\n",
 838                         opts->transport);
 839                 ret = -EINVAL;
 840                 goto out_unlock;
 841         }
 842
 843         ret = nvmf_check_required_opts(opts, ops->required_opts);
 844         if (ret)
 845                 goto out_unlock;
 846         ret = nvmf_check_allowed_opts(opts, NVMF_ALLOWED_OPTS |
 847                                 ops->allowed_opts | ops->required_opts);
 848         if (ret)
 849                 goto out_unlock;
 850
 851         ctrl = ops->create_ctrl(dev, opts);
 852         if (IS_ERR(ctrl)) {
 853                 ret = PTR_ERR(ctrl);
 854                 goto out_unlock;
 855         }
 856
 857         mutex_unlock(&nvmf_transports_mutex);
 858         return ctrl;
 859
 860 out_unlock:
 861         mutex_unlock(&nvmf_transports_mutex);
 862 out_free_opts:
 863         nvmf_free_options(opts);
 864         return ERR_PTR(ret);
 865 }
 866
 867 static struct class *nvmf_class;
 868 static struct device *nvmf_device;
 869 static DEFINE_MUTEX(nvmf_dev_mutex);
 870
 871 static ssize_t nvmf_dev_write(struct file *file, const char __user *ubuf,
 872                 size_t count, loff_t *pos)
 873 {
 874         struct seq_file *seq_file = file->private_data;
 875         struct nvme_ctrl *ctrl;
 876         const char *buf;
 877         int ret = 0;
 878
 879         if (count > PAGE_SIZE)
 880                 return -ENOMEM;
 881
 882         buf = memdup_user_nul(ubuf, count);
 883         if (IS_ERR(buf))
 884                 return PTR_ERR(buf);
 885
 886         mutex_lock(&nvmf_dev_mutex);
 887         if (seq_file->private) {
 888                 ret = -EINVAL;
 889                 goto out_unlock;
 890         }
 891
 892         ctrl = nvmf_create_ctrl(nvmf_device, buf, count);
 893         if (IS_ERR(ctrl)) {
 894                 ret = PTR_ERR(ctrl);
 895                 goto out_unlock;
 896         }
 897
 898         seq_file->private = ctrl;
 899
 900 out_unlock:
 901         mutex_unlock(&nvmf_dev_mutex);
 902         kfree(buf);
 903         return ret ? ret : count;
 904 }
 905
 906 static int nvmf_dev_show(struct seq_file *seq_file, void *private)
 907 {
 908         struct nvme_ctrl *ctrl;
 909         int ret = 0;
 910
 911         mutex_lock(&nvmf_dev_mutex);
 912         ctrl = seq_file->private;
 913         if (!ctrl) {
 914                 ret = -EINVAL;
 915                 goto out_unlock;
 916         }
 917
 918         seq_printf(seq_file, "instance=%d,cntlid=%d\n",
 919                         ctrl->instance, ctrl->cntlid);
 920
 921 out_unlock:
 922         mutex_unlock(&nvmf_dev_mutex);
 923         return ret;
 924 }
 925
 926 static int nvmf_dev_open(struct inode *inode, struct file *file)
 927 {
 928         /*
 929          * The miscdevice code initializes file->private_data, but doesn't
 930          * make use of it later.
 931          */
 932         file->private_data = NULL;
 933         return single_open(file, nvmf_dev_show, NULL);
 934 }
 935
 936 static int nvmf_dev_release(struct inode *inode, struct file *file)
 937 {
 938         struct seq_file *seq_file = file->private_data;
 939         struct nvme_ctrl *ctrl = seq_file->private;
 940
 941         if (ctrl)
 942                 nvme_put_ctrl(ctrl);
 943         return single_release(inode, file);
 944 }
 945
 946 static const struct file_operations nvmf_dev_fops = {
 947         .owner          = THIS_MODULE,
 948         .write          = nvmf_dev_write,
 949         .read           = seq_read,
 950         .open           = nvmf_dev_open,
 951         .release        = nvmf_dev_release,
 952 };
 953
 954 static struct miscdevice nvmf_misc = {
 955         .minor          = MISC_DYNAMIC_MINOR,
 956         .name           = "nvme-fabrics",
 957         .fops           = &nvmf_dev_fops,
 958 };
 959
 960 static int __init nvmf_init(void)
 961 {
 962         int ret;
 963
 964         nvmf_default_host = nvmf_host_default();
 965         if (!nvmf_default_host)
 966                 return -ENOMEM;
 967
 968         nvmf_class = class_create(THIS_MODULE, "nvme-fabrics");
 969         if (IS_ERR(nvmf_class)) {
 970                 pr_err("couldn't register class nvme-fabrics\n");
 971                 ret = PTR_ERR(nvmf_class);
 972                 goto out_free_host;
 973         }
 974
 975         nvmf_device =
 976                 device_create(nvmf_class, NULL, MKDEV(0, 0), NULL, "ctl");
 977         if (IS_ERR(nvmf_device)) {
 978                 pr_err("couldn't create nvme-fabris device!\n");
 979                 ret = PTR_ERR(nvmf_device);
 980                 goto out_destroy_class;
 981         }
 982
 983         ret = misc_register(&nvmf_misc);
 984         if (ret) {
 985                 pr_err("couldn't register misc device: %d\n", ret);
 986                 goto out_destroy_device;
 987         }
 988
 989         return 0;
 990
 991 out_destroy_device:
 992         device_destroy(nvmf_class, MKDEV(0, 0));
 993 out_destroy_class:
 994         class_destroy(nvmf_class);
 995 out_free_host:
 996         nvmf_host_put(nvmf_default_host);
 997         return ret;
 998 }
 999
1000 static void __exit nvmf_exit(void)
1001 {
1002         misc_deregister(&nvmf_misc);
1003         device_destroy(nvmf_class, MKDEV(0, 0));
1004         class_destroy(nvmf_class);
1005         nvmf_host_put(nvmf_default_host);
1006
1007         BUILD_BUG_ON(sizeof(struct nvmf_connect_command) != 64);
1008         BUILD_BUG_ON(sizeof(struct nvmf_property_get_command) != 64);
1009         BUILD_BUG_ON(sizeof(struct nvmf_property_set_command) != 64);
1010         BUILD_BUG_ON(sizeof(struct nvmf_connect_data) != 1024);
1011 }
1012
1013 MODULE_LICENSE("GPL v2");
1014
1015 module_init(nvmf_init);
1016 module_exit(nvmf_exit);