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 DECLARE_RWSEM(nvmf_transports_rwsem);
  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         uuid_gen(&host->id);
  78         snprintf(host->nqn, NVMF_NQN_SIZE,
  79                 "nqn.2014-08.org.nvmexpress:uuid:%pUb", &host->id);
  80
  81         mutex_lock(&nvmf_hosts_mutex);
  82         list_add_tail(&host->list, &nvmf_hosts);
  83         mutex_unlock(&nvmf_hosts_mutex);
  84
  85         return host;
  86 }
  87
  88 static void nvmf_host_destroy(struct kref *ref)
  89 {
  90         struct nvmf_host *host = container_of(ref, struct nvmf_host, ref);
  91
  92         mutex_lock(&nvmf_hosts_mutex);
  93         list_del(&host->list);
  94         mutex_unlock(&nvmf_hosts_mutex);
  95
  96         kfree(host);
  97 }
  98
  99 static void nvmf_host_put(struct nvmf_host *host)
 100 {
 101         if (host)
 102                 kref_put(&host->ref, nvmf_host_destroy);
 103 }
 104
 105 /**
 106  * nvmf_get_address() -  Get address/port
 107  * @ctrl:       Host NVMe controller instance which we got the address
 108  * @buf:        OUTPUT parameter that will contain the address/port
 109  * @size:       buffer size
 110  */
 111 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
 112 {
 113         int len = 0;
 114
 115         if (ctrl->opts->mask & NVMF_OPT_TRADDR)
 116                 len += snprintf(buf, size, "traddr=%s", ctrl->opts->traddr);
 117         if (ctrl->opts->mask & NVMF_OPT_TRSVCID)
 118                 len += snprintf(buf + len, size - len, "%strsvcid=%s",
 119                                 (len) ? "," : "", ctrl->opts->trsvcid);
 120         if (ctrl->opts->mask & NVMF_OPT_HOST_TRADDR)
 121                 len += snprintf(buf + len, size - len, "%shost_traddr=%s",
 122                                 (len) ? "," : "", ctrl->opts->host_traddr);
 123         len += snprintf(buf + len, size - len, "\n");
 124
 125         return len;
 126 }
 127 EXPORT_SYMBOL_GPL(nvmf_get_address);
 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         union nvme_result res;
 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, &res, NULL, 0, 0,
 162                         NVME_QID_ANY, 0, 0);
 163
 164         if (ret >= 0)
 165                 *val = le64_to_cpu(res.u64);
 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         union nvme_result res;
 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, &res, NULL, 0, 0,
 209                         NVME_QID_ANY, 0, 0);
 210
 211         if (ret >= 0)
 212                 *val = le64_to_cpu(res.u64);
 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
 330         case NVME_SC_CONNECT_INVALID_HOST:
 331                 dev_err(ctrl->device,
 332                         "Connect for subsystem %s is not allowed, hostnqn: %s\n",
 333                         data->subsysnqn, data->hostnqn);
 334                 break;
 335
 336         case NVME_SC_CONNECT_CTRL_BUSY:
 337                 dev_err(ctrl->device,
 338                         "Connect command failed: controller is busy or not available\n");
 339                 break;
 340
 341         case NVME_SC_CONNECT_FORMAT:
 342                 dev_err(ctrl->device,
 343                         "Connect incompatible format: %d",
 344                         cmd->connect.recfmt);
 345                 break;
 346
 347         default:
 348                 dev_err(ctrl->device,
 349                         "Connect command failed, error wo/DNR bit: %d\n",
 350                         err_sctype);
 351                 break;
 352         } /* switch (err_sctype) */
 353 }
 354
 355 /**
 356  * nvmf_connect_admin_queue() - NVMe Fabrics Admin Queue "Connect"
 357  *                              API function.
 358  * @ctrl:       Host nvme controller instance used to request
 359  *              a new NVMe controller allocation on the target
 360  *              system and  establish an NVMe Admin connection to
 361  *              that controller.
 362  *
 363  * This function enables an NVMe host device to request a new allocation of
 364  * an NVMe controller resource on a target system as well establish a
 365  * fabrics-protocol connection of the NVMe Admin queue between the
 366  * host system device and the allocated NVMe controller on the
 367  * target system via a NVMe Fabrics "Connect" command.
 368  *
 369  * Return:
 370  *      0: success
 371  *      > 0: NVMe error status code
 372  *      < 0: Linux errno error code
 373  *
 374  */
 375 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
 376 {
 377         struct nvme_command cmd;
 378         union nvme_result res;
 379         struct nvmf_connect_data *data;
 380         int ret;
 381
 382         memset(&cmd, 0, sizeof(cmd));
 383         cmd.connect.opcode = nvme_fabrics_command;
 384         cmd.connect.fctype = nvme_fabrics_type_connect;
 385         cmd.connect.qid = 0;
 386         cmd.connect.sqsize = cpu_to_le16(NVME_AQ_DEPTH - 1);
 387
 388         /*
 389          * Set keep-alive timeout in seconds granularity (ms * 1000)
 390          * and add a grace period for controller kato enforcement
 391          */
 392         cmd.connect.kato = ctrl->opts->discovery_nqn ? 0 :
 393                 cpu_to_le32((ctrl->kato + NVME_KATO_GRACE) * 1000);
 394
 395         data = kzalloc(sizeof(*data), GFP_KERNEL);
 396         if (!data)
 397                 return -ENOMEM;
 398
 399         uuid_copy(&data->hostid, &ctrl->opts->host->id);
 400         data->cntlid = cpu_to_le16(0xffff);
 401         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
 402         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
 403
 404         ret = __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, &res,
 405                         data, sizeof(*data), 0, NVME_QID_ANY, 1,
 406                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
 407         if (ret) {
 408                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(res.u32),
 409                                        &cmd, data);
 410                 goto out_free_data;
 411         }
 412
 413         ctrl->cntlid = le16_to_cpu(res.u16);
 414
 415 out_free_data:
 416         kfree(data);
 417         return ret;
 418 }
 419 EXPORT_SYMBOL_GPL(nvmf_connect_admin_queue);
 420
 421 /**
 422  * nvmf_connect_io_queue() - NVMe Fabrics I/O Queue "Connect"
 423  *                           API function.
 424  * @ctrl:       Host nvme controller instance used to establish an
 425  *              NVMe I/O queue connection to the already allocated NVMe
 426  *              controller on the target system.
 427  * @qid:        NVMe I/O queue number for the new I/O connection between
 428  *              host and target (note qid == 0 is illegal as this is
 429  *              the Admin queue, per NVMe standard).
 430  *
 431  * This function issues a fabrics-protocol connection
 432  * of a NVMe I/O queue (via NVMe Fabrics "Connect" command)
 433  * between the host system device and the allocated NVMe controller
 434  * on the target system.
 435  *
 436  * Return:
 437  *      0: success
 438  *      > 0: NVMe error status code
 439  *      < 0: Linux errno error code
 440  */
 441 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid)
 442 {
 443         struct nvme_command cmd;
 444         struct nvmf_connect_data *data;
 445         union nvme_result res;
 446         int ret;
 447
 448         memset(&cmd, 0, sizeof(cmd));
 449         cmd.connect.opcode = nvme_fabrics_command;
 450         cmd.connect.fctype = nvme_fabrics_type_connect;
 451         cmd.connect.qid = cpu_to_le16(qid);
 452         cmd.connect.sqsize = cpu_to_le16(ctrl->sqsize);
 453
 454         data = kzalloc(sizeof(*data), GFP_KERNEL);
 455         if (!data)
 456                 return -ENOMEM;
 457
 458         uuid_copy(&data->hostid, &ctrl->opts->host->id);
 459         data->cntlid = cpu_to_le16(ctrl->cntlid);
 460         strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
 461         strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
 462
 463         ret = __nvme_submit_sync_cmd(ctrl->connect_q, &cmd, &res,
 464                         data, sizeof(*data), 0, qid, 1,
 465                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
 466         if (ret) {
 467                 nvmf_log_connect_error(ctrl, ret, le32_to_cpu(res.u32),
 468                                        &cmd, data);
 469         }
 470         kfree(data);
 471         return ret;
 472 }
 473 EXPORT_SYMBOL_GPL(nvmf_connect_io_queue);
 474
 475 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl)
 476 {
 477         if (ctrl->opts->max_reconnects != -1 &&
 478             ctrl->nr_reconnects < ctrl->opts->max_reconnects)
 479                 return true;
 480
 481         return false;
 482 }
 483 EXPORT_SYMBOL_GPL(nvmf_should_reconnect);
 484
 485 /**
 486  * nvmf_register_transport() - NVMe Fabrics Library registration function.
 487  * @ops:        Transport ops instance to be registered to the
 488  *              common fabrics library.
 489  *
 490  * API function that registers the type of specific transport fabric
 491  * being implemented to the common NVMe fabrics library. Part of
 492  * the overall init sequence of starting up a fabrics driver.
 493  */
 494 int nvmf_register_transport(struct nvmf_transport_ops *ops)
 495 {
 496         if (!ops->create_ctrl)
 497                 return -EINVAL;
 498
 499         down_write(&nvmf_transports_rwsem);
 500         list_add_tail(&ops->entry, &nvmf_transports);
 501         up_write(&nvmf_transports_rwsem);
 502
 503         return 0;
 504 }
 505 EXPORT_SYMBOL_GPL(nvmf_register_transport);
 506
 507 /**
 508  * nvmf_unregister_transport() - NVMe Fabrics Library unregistration function.
 509  * @ops:        Transport ops instance to be unregistered from the
 510  *              common fabrics library.
 511  *
 512  * Fabrics API function that unregisters the type of specific transport
 513  * fabric being implemented from the common NVMe fabrics library.
 514  * Part of the overall exit sequence of unloading the implemented driver.
 515  */
 516 void nvmf_unregister_transport(struct nvmf_transport_ops *ops)
 517 {
 518         down_write(&nvmf_transports_rwsem);
 519         list_del(&ops->entry);
 520         up_write(&nvmf_transports_rwsem);
 521 }
 522 EXPORT_SYMBOL_GPL(nvmf_unregister_transport);
 523
 524 static struct nvmf_transport_ops *nvmf_lookup_transport(
 525                 struct nvmf_ctrl_options *opts)
 526 {
 527         struct nvmf_transport_ops *ops;
 528
 529         lockdep_assert_held(&nvmf_transports_rwsem);
 530
 531         list_for_each_entry(ops, &nvmf_transports, entry) {
 532                 if (strcmp(ops->name, opts->transport) == 0)
 533                         return ops;
 534         }
 535
 536         return NULL;
 537 }
 538
 539 blk_status_t nvmf_check_if_ready(struct nvme_ctrl *ctrl, struct request *rq,
 540                 bool queue_live, bool is_connected)
 541 {
 542         struct nvme_command *cmd = nvme_req(rq)->cmd;
 543
 544         if (likely(ctrl->state == NVME_CTRL_LIVE && is_connected))
 545                 return BLK_STS_OK;
 546
 547         switch (ctrl->state) {
 548         case NVME_CTRL_DELETING:
 549                 goto reject_io;
 550
 551         case NVME_CTRL_NEW:
 552         case NVME_CTRL_CONNECTING:
 553                 if (!is_connected)
 554                         /*
 555                          * This is the case of starting a new
 556                          * association but connectivity was lost
 557                          * before it was fully created. We need to
 558                          * error the commands used to initialize the
 559                          * controller so the reconnect can go into a
 560                          * retry attempt. The commands should all be
 561                          * marked REQ_FAILFAST_DRIVER, which will hit
 562                          * the reject path below. Anything else will
 563                          * be queued while the state settles.
 564                          */
 565                         goto reject_or_queue_io;
 566
 567                 if ((queue_live &&
 568                      !(nvme_req(rq)->flags & NVME_REQ_USERCMD)) ||
 569                     (!queue_live && blk_rq_is_passthrough(rq) &&
 570                      cmd->common.opcode == nvme_fabrics_command &&
 571                      cmd->fabrics.fctype == nvme_fabrics_type_connect))
 572                         /*
 573                          * If queue is live, allow only commands that
 574                          * are internally generated pass through. These
 575                          * are commands on the admin queue to initialize
 576                          * the controller. This will reject any ioctl
 577                          * admin cmds received while initializing.
 578                          *
 579                          * If the queue is not live, allow only a
 580                          * connect command. This will reject any ioctl
 581                          * admin cmd as well as initialization commands
 582                          * if the controller reverted the queue to non-live.
 583                          */
 584                         return BLK_STS_OK;
 585
 586                 /*
 587                  * fall-thru to the reject_or_queue_io clause
 588                  */
 589                 break;
 590
 591         /* these cases fall-thru
 592          * case NVME_CTRL_LIVE:
 593          * case NVME_CTRL_RESETTING:
 594          */
 595         default:
 596                 break;
 597         }
 598
 599 reject_or_queue_io:
 600         /*
 601          * Any other new io is something we're not in a state to send
 602          * to the device. Default action is to busy it and retry it
 603          * after the controller state is recovered. However, anything
 604          * marked for failfast or nvme multipath is immediately failed.
 605          * Note: commands used to initialize the controller will be
 606          *  marked for failfast.
 607          * Note: nvme cli/ioctl commands are marked for failfast.
 608          */
 609         if (!blk_noretry_request(rq) && !(rq->cmd_flags & REQ_NVME_MPATH))
 610                 return BLK_STS_RESOURCE;
 611
 612 reject_io:
 613         nvme_req(rq)->status = NVME_SC_ABORT_REQ;
 614         return BLK_STS_IOERR;
 615 }
 616 EXPORT_SYMBOL_GPL(nvmf_check_if_ready);
 617
 618 static const match_table_t opt_tokens = {
 619         { NVMF_OPT_TRANSPORT,           "transport=%s"          },
 620         { NVMF_OPT_TRADDR,              "traddr=%s"             },
 621         { NVMF_OPT_TRSVCID,             "trsvcid=%s"            },
 622         { NVMF_OPT_NQN,                 "nqn=%s"                },
 623         { NVMF_OPT_QUEUE_SIZE,          "queue_size=%d"         },
 624         { NVMF_OPT_NR_IO_QUEUES,        "nr_io_queues=%d"       },
 625         { NVMF_OPT_RECONNECT_DELAY,     "reconnect_delay=%d"    },
 626         { NVMF_OPT_CTRL_LOSS_TMO,       "ctrl_loss_tmo=%d"      },
 627         { NVMF_OPT_KATO,                "keep_alive_tmo=%d"     },
 628         { NVMF_OPT_HOSTNQN,             "hostnqn=%s"            },
 629         { NVMF_OPT_HOST_TRADDR,         "host_traddr=%s"        },
 630         { NVMF_OPT_HOST_ID,             "hostid=%s"             },
 631         { NVMF_OPT_DUP_CONNECT,         "duplicate_connect"     },
 632         { NVMF_OPT_ERR,                 NULL                    }
 633 };
 634
 635 static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
 636                 const char *buf)
 637 {
 638         substring_t args[MAX_OPT_ARGS];
 639         char *options, *o, *p;
 640         int token, ret = 0;
 641         size_t nqnlen  = 0;
 642         int ctrl_loss_tmo = NVMF_DEF_CTRL_LOSS_TMO;
 643         uuid_t hostid;
 644
 645         /* Set defaults */
 646         opts->queue_size = NVMF_DEF_QUEUE_SIZE;
 647         opts->nr_io_queues = num_online_cpus();
 648         opts->reconnect_delay = NVMF_DEF_RECONNECT_DELAY;
 649         opts->kato = NVME_DEFAULT_KATO;
 650         opts->duplicate_connect = false;
 651
 652         options = o = kstrdup(buf, GFP_KERNEL);
 653         if (!options)
 654                 return -ENOMEM;
 655
 656         uuid_gen(&hostid);
 657
 658         while ((p = strsep(&o, ",\n")) != NULL) {
 659                 if (!*p)
 660                         continue;
 661
 662                 token = match_token(p, opt_tokens, args);
 663                 opts->mask |= token;
 664                 switch (token) {
 665                 case NVMF_OPT_TRANSPORT:
 666                         p = match_strdup(args);
 667                         if (!p) {
 668                                 ret = -ENOMEM;
 669                                 goto out;
 670                         }
 671                         opts->transport = p;
 672                         break;
 673                 case NVMF_OPT_NQN:
 674                         p = match_strdup(args);
 675                         if (!p) {
 676                                 ret = -ENOMEM;
 677                                 goto out;
 678                         }
 679                         opts->subsysnqn = p;
 680                         nqnlen = strlen(opts->subsysnqn);
 681                         if (nqnlen >= NVMF_NQN_SIZE) {
 682                                 pr_err("%s needs to be < %d bytes\n",
 683                                         opts->subsysnqn, NVMF_NQN_SIZE);
 684                                 ret = -EINVAL;
 685                                 goto out;
 686                         }
 687                         opts->discovery_nqn =
 688                                 !(strcmp(opts->subsysnqn,
 689                                          NVME_DISC_SUBSYS_NAME));
 690                         if (opts->discovery_nqn) {
 691                                 opts->kato = 0;
 692                                 opts->nr_io_queues = 0;
 693                         }
 694                         break;
 695                 case NVMF_OPT_TRADDR:
 696                         p = match_strdup(args);
 697                         if (!p) {
 698                                 ret = -ENOMEM;
 699                                 goto out;
 700                         }
 701                         opts->traddr = p;
 702                         break;
 703                 case NVMF_OPT_TRSVCID:
 704                         p = match_strdup(args);
 705                         if (!p) {
 706                                 ret = -ENOMEM;
 707                                 goto out;
 708                         }
 709                         opts->trsvcid = p;
 710                         break;
 711                 case NVMF_OPT_QUEUE_SIZE:
 712                         if (match_int(args, &token)) {
 713                                 ret = -EINVAL;
 714                                 goto out;
 715                         }
 716                         if (token < NVMF_MIN_QUEUE_SIZE ||
 717                             token > NVMF_MAX_QUEUE_SIZE) {
 718                                 pr_err("Invalid queue_size %d\n", token);
 719                                 ret = -EINVAL;
 720                                 goto out;
 721                         }
 722                         opts->queue_size = token;
 723                         break;
 724                 case NVMF_OPT_NR_IO_QUEUES:
 725                         if (match_int(args, &token)) {
 726                                 ret = -EINVAL;
 727                                 goto out;
 728                         }
 729                         if (token <= 0) {
 730                                 pr_err("Invalid number of IOQs %d\n", token);
 731                                 ret = -EINVAL;
 732                                 goto out;
 733                         }
 734                         if (opts->discovery_nqn) {
 735                                 pr_debug("Ignoring nr_io_queues value for discovery controller\n");
 736                                 break;
 737                         }
 738
 739                         opts->nr_io_queues = min_t(unsigned int,
 740                                         num_online_cpus(), token);
 741                         break;
 742                 case NVMF_OPT_KATO:
 743                         if (match_int(args, &token)) {
 744                                 ret = -EINVAL;
 745                                 goto out;
 746                         }
 747
 748                         if (token < 0) {
 749                                 pr_err("Invalid keep_alive_tmo %d\n", token);
 750                                 ret = -EINVAL;
 751                                 goto out;
 752                         } else if (token == 0 && !opts->discovery_nqn) {
 753                                 /* Allowed for debug */
 754                                 pr_warn("keep_alive_tmo 0 won't execute keep alives!!!\n");
 755                         }
 756                         opts->kato = token;
 757
 758                         if (opts->discovery_nqn && opts->kato) {
 759                                 pr_err("Discovery controllers cannot accept KATO != 0\n");
 760                                 ret = -EINVAL;
 761                                 goto out;
 762                         }
 763
 764                         break;
 765                 case NVMF_OPT_CTRL_LOSS_TMO:
 766                         if (match_int(args, &token)) {
 767                                 ret = -EINVAL;
 768                                 goto out;
 769                         }
 770
 771                         if (token < 0)
 772                                 pr_warn("ctrl_loss_tmo < 0 will reconnect forever\n");
 773                         ctrl_loss_tmo = token;
 774                         break;
 775                 case NVMF_OPT_HOSTNQN:
 776                         if (opts->host) {
 777                                 pr_err("hostnqn already user-assigned: %s\n",
 778                                        opts->host->nqn);
 779                                 ret = -EADDRINUSE;
 780                                 goto out;
 781                         }
 782                         p = match_strdup(args);
 783                         if (!p) {
 784                                 ret = -ENOMEM;
 785                                 goto out;
 786                         }
 787                         nqnlen = strlen(p);
 788                         if (nqnlen >= NVMF_NQN_SIZE) {
 789                                 pr_err("%s needs to be < %d bytes\n",
 790                                         p, NVMF_NQN_SIZE);
 791                                 kfree(p);
 792                                 ret = -EINVAL;
 793                                 goto out;
 794                         }
 795                         opts->host = nvmf_host_add(p);
 796                         kfree(p);
 797                         if (!opts->host) {
 798                                 ret = -ENOMEM;
 799                                 goto out;
 800                         }
 801                         break;
 802                 case NVMF_OPT_RECONNECT_DELAY:
 803                         if (match_int(args, &token)) {
 804                                 ret = -EINVAL;
 805                                 goto out;
 806                         }
 807                         if (token <= 0) {
 808                                 pr_err("Invalid reconnect_delay %d\n", token);
 809                                 ret = -EINVAL;
 810                                 goto out;
 811                         }
 812                         opts->reconnect_delay = token;
 813                         break;
 814                 case NVMF_OPT_HOST_TRADDR:
 815                         p = match_strdup(args);
 816                         if (!p) {
 817                                 ret = -ENOMEM;
 818                                 goto out;
 819                         }
 820                         opts->host_traddr = p;
 821                         break;
 822                 case NVMF_OPT_HOST_ID:
 823                         p = match_strdup(args);
 824                         if (!p) {
 825                                 ret = -ENOMEM;
 826                                 goto out;
 827                         }
 828                         ret = uuid_parse(p, &hostid);
 829                         if (ret) {
 830                                 pr_err("Invalid hostid %s\n", p);
 831                                 ret = -EINVAL;
 832                                 kfree(p);
 833                                 goto out;
 834                         }
 835                         kfree(p);
 836                         break;
 837                 case NVMF_OPT_DUP_CONNECT:
 838                         opts->duplicate_connect = true;
 839                         break;
 840                 default:
 841                         pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
 842                                 p);
 843                         ret = -EINVAL;
 844                         goto out;
 845                 }
 846         }
 847
 848         if (ctrl_loss_tmo < 0)
 849                 opts->max_reconnects = -1;
 850         else
 851                 opts->max_reconnects = DIV_ROUND_UP(ctrl_loss_tmo,
 852                                                 opts->reconnect_delay);
 853
 854         if (!opts->host) {
 855                 kref_get(&nvmf_default_host->ref);
 856                 opts->host = nvmf_default_host;
 857         }
 858
 859         uuid_copy(&opts->host->id, &hostid);
 860
 861 out:
 862         kfree(options);
 863         return ret;
 864 }
 865
 866 static int nvmf_check_required_opts(struct nvmf_ctrl_options *opts,
 867                 unsigned int required_opts)
 868 {
 869         if ((opts->mask & required_opts) != required_opts) {
 870                 int i;
 871
 872                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
 873                         if ((opt_tokens[i].token & required_opts) &&
 874                             !(opt_tokens[i].token & opts->mask)) {
 875                                 pr_warn("missing parameter '%s'\n",
 876                                         opt_tokens[i].pattern);
 877                         }
 878                 }
 879
 880                 return -EINVAL;
 881         }
 882
 883         return 0;
 884 }
 885
 886 static int nvmf_check_allowed_opts(struct nvmf_ctrl_options *opts,
 887                 unsigned int allowed_opts)
 888 {
 889         if (opts->mask & ~allowed_opts) {
 890                 int i;
 891
 892                 for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
 893                         if ((opt_tokens[i].token & opts->mask) &&
 894                             (opt_tokens[i].token & ~allowed_opts)) {
 895                                 pr_warn("invalid parameter '%s'\n",
 896                                         opt_tokens[i].pattern);
 897                         }
 898                 }
 899
 900                 return -EINVAL;
 901         }
 902
 903         return 0;
 904 }
 905
 906 void nvmf_free_options(struct nvmf_ctrl_options *opts)
 907 {
 908         nvmf_host_put(opts->host);
 909         kfree(opts->transport);
 910         kfree(opts->traddr);
 911         kfree(opts->trsvcid);
 912         kfree(opts->subsysnqn);
 913         kfree(opts->host_traddr);
 914         kfree(opts);
 915 }
 916 EXPORT_SYMBOL_GPL(nvmf_free_options);
 917
 918 #define NVMF_REQUIRED_OPTS      (NVMF_OPT_TRANSPORT | NVMF_OPT_NQN)
 919 #define NVMF_ALLOWED_OPTS       (NVMF_OPT_QUEUE_SIZE | NVMF_OPT_NR_IO_QUEUES | \
 920                                  NVMF_OPT_KATO | NVMF_OPT_HOSTNQN | \
 921                                  NVMF_OPT_HOST_ID | NVMF_OPT_DUP_CONNECT)
 922
 923 static struct nvme_ctrl *
 924 nvmf_create_ctrl(struct device *dev, const char *buf, size_t count)
 925 {
 926         struct nvmf_ctrl_options *opts;
 927         struct nvmf_transport_ops *ops;
 928         struct nvme_ctrl *ctrl;
 929         int ret;
 930
 931         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 932         if (!opts)
 933                 return ERR_PTR(-ENOMEM);
 934
 935         ret = nvmf_parse_options(opts, buf);
 936         if (ret)
 937                 goto out_free_opts;
 938
 939
 940         request_module("nvme-%s", opts->transport);
 941
 942         /*
 943          * Check the generic options first as we need a valid transport for
 944          * the lookup below.  Then clear the generic flags so that transport
 945          * drivers don't have to care about them.
 946          */
 947         ret = nvmf_check_required_opts(opts, NVMF_REQUIRED_OPTS);
 948         if (ret)
 949                 goto out_free_opts;
 950         opts->mask &= ~NVMF_REQUIRED_OPTS;
 951
 952         down_read(&nvmf_transports_rwsem);
 953         ops = nvmf_lookup_transport(opts);
 954         if (!ops) {
 955                 pr_info("no handler found for transport %s.\n",
 956                         opts->transport);
 957                 ret = -EINVAL;
 958                 goto out_unlock;
 959         }
 960
 961         if (!try_module_get(ops->module)) {
 962                 ret = -EBUSY;
 963                 goto out_unlock;
 964         }
 965
 966         ret = nvmf_check_required_opts(opts, ops->required_opts);
 967         if (ret)
 968                 goto out_module_put;
 969         ret = nvmf_check_allowed_opts(opts, NVMF_ALLOWED_OPTS |
 970                                 ops->allowed_opts | ops->required_opts);
 971         if (ret)
 972                 goto out_module_put;
 973
 974         ctrl = ops->create_ctrl(dev, opts);
 975         if (IS_ERR(ctrl)) {
 976                 ret = PTR_ERR(ctrl);
 977                 goto out_module_put;
 978         }
 979
 980         if (strcmp(ctrl->subsys->subnqn, opts->subsysnqn)) {
 981                 dev_warn(ctrl->device,
 982                         "controller returned incorrect NQN: \"%s\".\n",
 983                         ctrl->subsys->subnqn);
 984                 module_put(ops->module);
 985                 up_read(&nvmf_transports_rwsem);
 986                 nvme_delete_ctrl_sync(ctrl);
 987                 return ERR_PTR(-EINVAL);
 988         }
 989
 990         module_put(ops->module);
 991         up_read(&nvmf_transports_rwsem);
 992         return ctrl;
 993
 994 out_module_put:
 995         module_put(ops->module);
 996 out_unlock:
 997         up_read(&nvmf_transports_rwsem);
 998 out_free_opts:
 999         nvmf_free_options(opts);
1000         return ERR_PTR(ret);
1001 }
1002
1003 static struct class *nvmf_class;
1004 static struct device *nvmf_device;
1005 static DEFINE_MUTEX(nvmf_dev_mutex);
1006
1007 static ssize_t nvmf_dev_write(struct file *file, const char __user *ubuf,
1008                 size_t count, loff_t *pos)
1009 {
1010         struct seq_file *seq_file = file->private_data;
1011         struct nvme_ctrl *ctrl;
1012         const char *buf;
1013         int ret = 0;
1014
1015         if (count > PAGE_SIZE)
1016                 return -ENOMEM;
1017
1018         buf = memdup_user_nul(ubuf, count);
1019         if (IS_ERR(buf))
1020                 return PTR_ERR(buf);
1021
1022         mutex_lock(&nvmf_dev_mutex);
1023         if (seq_file->private) {
1024                 ret = -EINVAL;
1025                 goto out_unlock;
1026         }
1027
1028         ctrl = nvmf_create_ctrl(nvmf_device, buf, count);
1029         if (IS_ERR(ctrl)) {
1030                 ret = PTR_ERR(ctrl);
1031                 goto out_unlock;
1032         }
1033
1034         seq_file->private = ctrl;
1035
1036 out_unlock:
1037         mutex_unlock(&nvmf_dev_mutex);
1038         kfree(buf);
1039         return ret ? ret : count;
1040 }
1041
1042 static int nvmf_dev_show(struct seq_file *seq_file, void *private)
1043 {
1044         struct nvme_ctrl *ctrl;
1045         int ret = 0;
1046
1047         mutex_lock(&nvmf_dev_mutex);
1048         ctrl = seq_file->private;
1049         if (!ctrl) {
1050                 ret = -EINVAL;
1051                 goto out_unlock;
1052         }
1053
1054         seq_printf(seq_file, "instance=%d,cntlid=%d\n",
1055                         ctrl->instance, ctrl->cntlid);
1056
1057 out_unlock:
1058         mutex_unlock(&nvmf_dev_mutex);
1059         return ret;
1060 }
1061
1062 static int nvmf_dev_open(struct inode *inode, struct file *file)
1063 {
1064         /*
1065          * The miscdevice code initializes file->private_data, but doesn't
1066          * make use of it later.
1067          */
1068         file->private_data = NULL;
1069         return single_open(file, nvmf_dev_show, NULL);
1070 }
1071
1072 static int nvmf_dev_release(struct inode *inode, struct file *file)
1073 {
1074         struct seq_file *seq_file = file->private_data;
1075         struct nvme_ctrl *ctrl = seq_file->private;
1076
1077         if (ctrl)
1078                 nvme_put_ctrl(ctrl);
1079         return single_release(inode, file);
1080 }
1081
1082 static const struct file_operations nvmf_dev_fops = {
1083         .owner          = THIS_MODULE,
1084         .write          = nvmf_dev_write,
1085         .read           = seq_read,
1086         .open           = nvmf_dev_open,
1087         .release        = nvmf_dev_release,
1088 };
1089
1090 static struct miscdevice nvmf_misc = {
1091         .minor          = MISC_DYNAMIC_MINOR,
1092         .name           = "nvme-fabrics",
1093         .fops           = &nvmf_dev_fops,
1094 };
1095
1096 static int __init nvmf_init(void)
1097 {
1098         int ret;
1099
1100         nvmf_default_host = nvmf_host_default();
1101         if (!nvmf_default_host)
1102                 return -ENOMEM;
1103
1104         nvmf_class = class_create(THIS_MODULE, "nvme-fabrics");
1105         if (IS_ERR(nvmf_class)) {
1106                 pr_err("couldn't register class nvme-fabrics\n");
1107                 ret = PTR_ERR(nvmf_class);
1108                 goto out_free_host;
1109         }
1110
1111         nvmf_device =
1112                 device_create(nvmf_class, NULL, MKDEV(0, 0), NULL, "ctl");
1113         if (IS_ERR(nvmf_device)) {
1114                 pr_err("couldn't create nvme-fabris device!\n");
1115                 ret = PTR_ERR(nvmf_device);
1116                 goto out_destroy_class;
1117         }
1118
1119         ret = misc_register(&nvmf_misc);
1120         if (ret) {
1121                 pr_err("couldn't register misc device: %d\n", ret);
1122                 goto out_destroy_device;
1123         }
1124
1125         return 0;
1126
1127 out_destroy_device:
1128         device_destroy(nvmf_class, MKDEV(0, 0));
1129 out_destroy_class:
1130         class_destroy(nvmf_class);
1131 out_free_host:
1132         nvmf_host_put(nvmf_default_host);
1133         return ret;
1134 }
1135
1136 static void __exit nvmf_exit(void)
1137 {
1138         misc_deregister(&nvmf_misc);
1139         device_destroy(nvmf_class, MKDEV(0, 0));
1140         class_destroy(nvmf_class);
1141         nvmf_host_put(nvmf_default_host);
1142
1143         BUILD_BUG_ON(sizeof(struct nvmf_connect_command) != 64);
1144         BUILD_BUG_ON(sizeof(struct nvmf_property_get_command) != 64);
1145         BUILD_BUG_ON(sizeof(struct nvmf_property_set_command) != 64);
1146         BUILD_BUG_ON(sizeof(struct nvmf_connect_data) != 1024);
1147 }
1148
1149 MODULE_LICENSE("GPL v2");
1150
1151 module_init(nvmf_init);
1152 module_exit(nvmf_exit);