drivers/nvme/target/core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Common code for the NVMe target.
   4  * Copyright (c) 2015-2016 HGST, a Western Digital Company.
   5  */
   6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   7 #include <linux/module.h>
   8 #include <linux/random.h>
   9 #include <linux/rculist.h>
  10 #include <linux/pci-p2pdma.h>
  11 #include <linux/scatterlist.h>
  12
  13 #define CREATE_TRACE_POINTS
  14 #include "trace.h"
  15
  16 #include "nvmet.h"
  17
  18 struct workqueue_struct *buffered_io_wq;
  19 static const struct nvmet_fabrics_ops *nvmet_transports[NVMF_TRTYPE_MAX];
  20 static DEFINE_IDA(cntlid_ida);
  21
  22 /*
  23  * This read/write semaphore is used to synchronize access to configuration
  24  * information on a target system that will result in discovery log page
  25  * information change for at least one host.
  26  * The full list of resources to protected by this semaphore is:
  27  *
  28  *  - subsystems list
  29  *  - per-subsystem allowed hosts list
  30  *  - allow_any_host subsystem attribute
  31  *  - nvmet_genctr
  32  *  - the nvmet_transports array
  33  *
  34  * When updating any of those lists/structures write lock should be obtained,
  35  * while when reading (popolating discovery log page or checking host-subsystem
  36  * link) read lock is obtained to allow concurrent reads.
  37  */
  38 DECLARE_RWSEM(nvmet_config_sem);
  39
  40 u32 nvmet_ana_group_enabled[NVMET_MAX_ANAGRPS + 1];
  41 u64 nvmet_ana_chgcnt;
  42 DECLARE_RWSEM(nvmet_ana_sem);
  43
  44 inline u16 errno_to_nvme_status(struct nvmet_req *req, int errno)
  45 {
  46         u16 status;
  47
  48         switch (errno) {
  49         case 0:
  50                 status = NVME_SC_SUCCESS;
  51                 break;
  52         case -ENOSPC:
  53                 req->error_loc = offsetof(struct nvme_rw_command, length);
  54                 status = NVME_SC_CAP_EXCEEDED | NVME_SC_DNR;
  55                 break;
  56         case -EREMOTEIO:
  57                 req->error_loc = offsetof(struct nvme_rw_command, slba);
  58                 status = NVME_SC_LBA_RANGE | NVME_SC_DNR;
  59                 break;
  60         case -EOPNOTSUPP:
  61                 req->error_loc = offsetof(struct nvme_common_command, opcode);
  62                 switch (req->cmd->common.opcode) {
  63                 case nvme_cmd_dsm:
  64                 case nvme_cmd_write_zeroes:
  65                         status = NVME_SC_ONCS_NOT_SUPPORTED | NVME_SC_DNR;
  66                         break;
  67                 default:
  68                         status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
  69                 }
  70                 break;
  71         case -ENODATA:
  72                 req->error_loc = offsetof(struct nvme_rw_command, nsid);
  73                 status = NVME_SC_ACCESS_DENIED;
  74                 break;
  75         case -EIO:
  76                 /* FALLTHRU */
  77         default:
  78                 req->error_loc = offsetof(struct nvme_common_command, opcode);
  79                 status = NVME_SC_INTERNAL | NVME_SC_DNR;
  80         }
  81
  82         return status;
  83 }
  84
  85 static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
  86                 const char *subsysnqn);
  87
  88 u16 nvmet_copy_to_sgl(struct nvmet_req *req, off_t off, const void *buf,
  89                 size_t len)
  90 {
  91         if (sg_pcopy_from_buffer(req->sg, req->sg_cnt, buf, len, off) != len) {
  92                 req->error_loc = offsetof(struct nvme_common_command, dptr);
  93                 return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
  94         }
  95         return 0;
  96 }
  97
  98 u16 nvmet_copy_from_sgl(struct nvmet_req *req, off_t off, void *buf, size_t len)
  99 {
 100         if (sg_pcopy_to_buffer(req->sg, req->sg_cnt, buf, len, off) != len) {
 101                 req->error_loc = offsetof(struct nvme_common_command, dptr);
 102                 return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
 103         }
 104         return 0;
 105 }
 106
 107 u16 nvmet_zero_sgl(struct nvmet_req *req, off_t off, size_t len)
 108 {
 109         if (sg_zero_buffer(req->sg, req->sg_cnt, len, off) != len) {
 110                 req->error_loc = offsetof(struct nvme_common_command, dptr);
 111                 return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
 112         }
 113         return 0;
 114 }
 115
 116 static unsigned int nvmet_max_nsid(struct nvmet_subsys *subsys)
 117 {
 118         struct nvmet_ns *ns;
 119
 120         if (list_empty(&subsys->namespaces))
 121                 return 0;
 122
 123         ns = list_last_entry(&subsys->namespaces, struct nvmet_ns, dev_link);
 124         return ns->nsid;
 125 }
 126
 127 static u32 nvmet_async_event_result(struct nvmet_async_event *aen)
 128 {
 129         return aen->event_type | (aen->event_info << 8) | (aen->log_page << 16);
 130 }
 131
 132 static void nvmet_async_events_free(struct nvmet_ctrl *ctrl)
 133 {
 134         struct nvmet_req *req;
 135
 136         while (1) {
 137                 mutex_lock(&ctrl->lock);
 138                 if (!ctrl->nr_async_event_cmds) {
 139                         mutex_unlock(&ctrl->lock);
 140                         return;
 141                 }
 142
 143                 req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds];
 144                 mutex_unlock(&ctrl->lock);
 145                 nvmet_req_complete(req, NVME_SC_INTERNAL | NVME_SC_DNR);
 146         }
 147 }
 148
 149 static void nvmet_async_event_work(struct work_struct *work)
 150 {
 151         struct nvmet_ctrl *ctrl =
 152                 container_of(work, struct nvmet_ctrl, async_event_work);
 153         struct nvmet_async_event *aen;
 154         struct nvmet_req *req;
 155
 156         while (1) {
 157                 mutex_lock(&ctrl->lock);
 158                 aen = list_first_entry_or_null(&ctrl->async_events,
 159                                 struct nvmet_async_event, entry);
 160                 if (!aen || !ctrl->nr_async_event_cmds) {
 161                         mutex_unlock(&ctrl->lock);
 162                         return;
 163                 }
 164
 165                 req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds];
 166                 nvmet_set_result(req, nvmet_async_event_result(aen));
 167
 168                 list_del(&aen->entry);
 169                 kfree(aen);
 170
 171                 mutex_unlock(&ctrl->lock);
 172                 nvmet_req_complete(req, 0);
 173         }
 174 }
 175
 176 void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type,
 177                 u8 event_info, u8 log_page)
 178 {
 179         struct nvmet_async_event *aen;
 180
 181         aen = kmalloc(sizeof(*aen), GFP_KERNEL);
 182         if (!aen)
 183                 return;
 184
 185         aen->event_type = event_type;
 186         aen->event_info = event_info;
 187         aen->log_page = log_page;
 188
 189         mutex_lock(&ctrl->lock);
 190         list_add_tail(&aen->entry, &ctrl->async_events);
 191         mutex_unlock(&ctrl->lock);
 192
 193         schedule_work(&ctrl->async_event_work);
 194 }
 195
 196 static void nvmet_add_to_changed_ns_log(struct nvmet_ctrl *ctrl, __le32 nsid)
 197 {
 198         u32 i;
 199
 200         mutex_lock(&ctrl->lock);
 201         if (ctrl->nr_changed_ns > NVME_MAX_CHANGED_NAMESPACES)
 202                 goto out_unlock;
 203
 204         for (i = 0; i < ctrl->nr_changed_ns; i++) {
 205                 if (ctrl->changed_ns_list[i] == nsid)
 206                         goto out_unlock;
 207         }
 208
 209         if (ctrl->nr_changed_ns == NVME_MAX_CHANGED_NAMESPACES) {
 210                 ctrl->changed_ns_list[0] = cpu_to_le32(0xffffffff);
 211                 ctrl->nr_changed_ns = U32_MAX;
 212                 goto out_unlock;
 213         }
 214
 215         ctrl->changed_ns_list[ctrl->nr_changed_ns++] = nsid;
 216 out_unlock:
 217         mutex_unlock(&ctrl->lock);
 218 }
 219
 220 void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid)
 221 {
 222         struct nvmet_ctrl *ctrl;
 223
 224         lockdep_assert_held(&subsys->lock);
 225
 226         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
 227                 nvmet_add_to_changed_ns_log(ctrl, cpu_to_le32(nsid));
 228                 if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_NS_ATTR))
 229                         continue;
 230                 nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE,
 231                                 NVME_AER_NOTICE_NS_CHANGED,
 232                                 NVME_LOG_CHANGED_NS);
 233         }
 234 }
 235
 236 void nvmet_send_ana_event(struct nvmet_subsys *subsys,
 237                 struct nvmet_port *port)
 238 {
 239         struct nvmet_ctrl *ctrl;
 240
 241         mutex_lock(&subsys->lock);
 242         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
 243                 if (port && ctrl->port != port)
 244                         continue;
 245                 if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_ANA_CHANGE))
 246                         continue;
 247                 nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE,
 248                                 NVME_AER_NOTICE_ANA, NVME_LOG_ANA);
 249         }
 250         mutex_unlock(&subsys->lock);
 251 }
 252
 253 void nvmet_port_send_ana_event(struct nvmet_port *port)
 254 {
 255         struct nvmet_subsys_link *p;
 256
 257         down_read(&nvmet_config_sem);
 258         list_for_each_entry(p, &port->subsystems, entry)
 259                 nvmet_send_ana_event(p->subsys, port);
 260         up_read(&nvmet_config_sem);
 261 }
 262
 263 int nvmet_register_transport(const struct nvmet_fabrics_ops *ops)
 264 {
 265         int ret = 0;
 266
 267         down_write(&nvmet_config_sem);
 268         if (nvmet_transports[ops->type])
 269                 ret = -EINVAL;
 270         else
 271                 nvmet_transports[ops->type] = ops;
 272         up_write(&nvmet_config_sem);
 273
 274         return ret;
 275 }
 276 EXPORT_SYMBOL_GPL(nvmet_register_transport);
 277
 278 void nvmet_unregister_transport(const struct nvmet_fabrics_ops *ops)
 279 {
 280         down_write(&nvmet_config_sem);
 281         nvmet_transports[ops->type] = NULL;
 282         up_write(&nvmet_config_sem);
 283 }
 284 EXPORT_SYMBOL_GPL(nvmet_unregister_transport);
 285
 286 void nvmet_port_del_ctrls(struct nvmet_port *port, struct nvmet_subsys *subsys)
 287 {
 288         struct nvmet_ctrl *ctrl;
 289
 290         mutex_lock(&subsys->lock);
 291         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
 292                 if (ctrl->port == port)
 293                         ctrl->ops->delete_ctrl(ctrl);
 294         }
 295         mutex_unlock(&subsys->lock);
 296 }
 297
 298 int nvmet_enable_port(struct nvmet_port *port)
 299 {
 300         const struct nvmet_fabrics_ops *ops;
 301         int ret;
 302
 303         lockdep_assert_held(&nvmet_config_sem);
 304
 305         ops = nvmet_transports[port->disc_addr.trtype];
 306         if (!ops) {
 307                 up_write(&nvmet_config_sem);
 308                 request_module("nvmet-transport-%d", port->disc_addr.trtype);
 309                 down_write(&nvmet_config_sem);
 310                 ops = nvmet_transports[port->disc_addr.trtype];
 311                 if (!ops) {
 312                         pr_err("transport type %d not supported\n",
 313                                 port->disc_addr.trtype);
 314                         return -EINVAL;
 315                 }
 316         }
 317
 318         if (!try_module_get(ops->owner))
 319                 return -EINVAL;
 320
 321         ret = ops->add_port(port);
 322         if (ret) {
 323                 module_put(ops->owner);
 324                 return ret;
 325         }
 326
 327         /* If the transport didn't set inline_data_size, then disable it. */
 328         if (port->inline_data_size < 0)
 329                 port->inline_data_size = 0;
 330
 331         port->enabled = true;
 332         port->tr_ops = ops;
 333         return 0;
 334 }
 335
 336 void nvmet_disable_port(struct nvmet_port *port)
 337 {
 338         const struct nvmet_fabrics_ops *ops;
 339
 340         lockdep_assert_held(&nvmet_config_sem);
 341
 342         port->enabled = false;
 343         port->tr_ops = NULL;
 344
 345         ops = nvmet_transports[port->disc_addr.trtype];
 346         ops->remove_port(port);
 347         module_put(ops->owner);
 348 }
 349
 350 static void nvmet_keep_alive_timer(struct work_struct *work)
 351 {
 352         struct nvmet_ctrl *ctrl = container_of(to_delayed_work(work),
 353                         struct nvmet_ctrl, ka_work);
 354         bool cmd_seen = ctrl->cmd_seen;
 355
 356         ctrl->cmd_seen = false;
 357         if (cmd_seen) {
 358                 pr_debug("ctrl %d reschedule traffic based keep-alive timer\n",
 359                         ctrl->cntlid);
 360                 schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
 361                 return;
 362         }
 363
 364         pr_err("ctrl %d keep-alive timer (%d seconds) expired!\n",
 365                 ctrl->cntlid, ctrl->kato);
 366
 367         nvmet_ctrl_fatal_error(ctrl);
 368 }
 369
 370 static void nvmet_start_keep_alive_timer(struct nvmet_ctrl *ctrl)
 371 {
 372         pr_debug("ctrl %d start keep-alive timer for %d secs\n",
 373                 ctrl->cntlid, ctrl->kato);
 374
 375         INIT_DELAYED_WORK(&ctrl->ka_work, nvmet_keep_alive_timer);
 376         schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
 377 }
 378
 379 static void nvmet_stop_keep_alive_timer(struct nvmet_ctrl *ctrl)
 380 {
 381         pr_debug("ctrl %d stop keep-alive\n", ctrl->cntlid);
 382
 383         cancel_delayed_work_sync(&ctrl->ka_work);
 384 }
 385
 386 static struct nvmet_ns *__nvmet_find_namespace(struct nvmet_ctrl *ctrl,
 387                 __le32 nsid)
 388 {
 389         struct nvmet_ns *ns;
 390
 391         list_for_each_entry_rcu(ns, &ctrl->subsys->namespaces, dev_link) {
 392                 if (ns->nsid == le32_to_cpu(nsid))
 393                         return ns;
 394         }
 395
 396         return NULL;
 397 }
 398
 399 struct nvmet_ns *nvmet_find_namespace(struct nvmet_ctrl *ctrl, __le32 nsid)
 400 {
 401         struct nvmet_ns *ns;
 402
 403         rcu_read_lock();
 404         ns = __nvmet_find_namespace(ctrl, nsid);
 405         if (ns)
 406                 percpu_ref_get(&ns->ref);
 407         rcu_read_unlock();
 408
 409         return ns;
 410 }
 411
 412 static void nvmet_destroy_namespace(struct percpu_ref *ref)
 413 {
 414         struct nvmet_ns *ns = container_of(ref, struct nvmet_ns, ref);
 415
 416         complete(&ns->disable_done);
 417 }
 418
 419 void nvmet_put_namespace(struct nvmet_ns *ns)
 420 {
 421         percpu_ref_put(&ns->ref);
 422 }
 423
 424 static void nvmet_ns_dev_disable(struct nvmet_ns *ns)
 425 {
 426         nvmet_bdev_ns_disable(ns);
 427         nvmet_file_ns_disable(ns);
 428 }
 429
 430 static int nvmet_p2pmem_ns_enable(struct nvmet_ns *ns)
 431 {
 432         int ret;
 433         struct pci_dev *p2p_dev;
 434
 435         if (!ns->use_p2pmem)
 436                 return 0;
 437
 438         if (!ns->bdev) {
 439                 pr_err("peer-to-peer DMA is not supported by non-block device namespaces\n");
 440                 return -EINVAL;
 441         }
 442
 443         if (!blk_queue_pci_p2pdma(ns->bdev->bd_queue)) {
 444                 pr_err("peer-to-peer DMA is not supported by the driver of %s\n",
 445                        ns->device_path);
 446                 return -EINVAL;
 447         }
 448
 449         if (ns->p2p_dev) {
 450                 ret = pci_p2pdma_distance(ns->p2p_dev, nvmet_ns_dev(ns), true);
 451                 if (ret < 0)
 452                         return -EINVAL;
 453         } else {
 454                 /*
 455                  * Right now we just check that there is p2pmem available so
 456                  * we can report an error to the user right away if there
 457                  * is not. We'll find the actual device to use once we
 458                  * setup the controller when the port's device is available.
 459                  */
 460
 461                 p2p_dev = pci_p2pmem_find(nvmet_ns_dev(ns));
 462                 if (!p2p_dev) {
 463                         pr_err("no peer-to-peer memory is available for %s\n",
 464                                ns->device_path);
 465                         return -EINVAL;
 466                 }
 467
 468                 pci_dev_put(p2p_dev);
 469         }
 470
 471         return 0;
 472 }
 473
 474 /*
 475  * Note: ctrl->subsys->lock should be held when calling this function
 476  */
 477 static void nvmet_p2pmem_ns_add_p2p(struct nvmet_ctrl *ctrl,
 478                                     struct nvmet_ns *ns)
 479 {
 480         struct device *clients[2];
 481         struct pci_dev *p2p_dev;
 482         int ret;
 483
 484         if (!ctrl->p2p_client || !ns->use_p2pmem)
 485                 return;
 486
 487         if (ns->p2p_dev) {
 488                 ret = pci_p2pdma_distance(ns->p2p_dev, ctrl->p2p_client, true);
 489                 if (ret < 0)
 490                         return;
 491
 492                 p2p_dev = pci_dev_get(ns->p2p_dev);
 493         } else {
 494                 clients[0] = ctrl->p2p_client;
 495                 clients[1] = nvmet_ns_dev(ns);
 496
 497                 p2p_dev = pci_p2pmem_find_many(clients, ARRAY_SIZE(clients));
 498                 if (!p2p_dev) {
 499                         pr_err("no peer-to-peer memory is available that's supported by %s and %s\n",
 500                                dev_name(ctrl->p2p_client), ns->device_path);
 501                         return;
 502                 }
 503         }
 504
 505         ret = radix_tree_insert(&ctrl->p2p_ns_map, ns->nsid, p2p_dev);
 506         if (ret < 0)
 507                 pci_dev_put(p2p_dev);
 508
 509         pr_info("using p2pmem on %s for nsid %d\n", pci_name(p2p_dev),
 510                 ns->nsid);
 511 }
 512
 513 int nvmet_ns_enable(struct nvmet_ns *ns)
 514 {
 515         struct nvmet_subsys *subsys = ns->subsys;
 516         struct nvmet_ctrl *ctrl;
 517         int ret;
 518
 519         mutex_lock(&subsys->lock);
 520         ret = 0;
 521         if (ns->enabled)
 522                 goto out_unlock;
 523
 524         ret = -EMFILE;
 525         if (subsys->nr_namespaces == NVMET_MAX_NAMESPACES)
 526                 goto out_unlock;
 527
 528         ret = nvmet_bdev_ns_enable(ns);
 529         if (ret == -ENOTBLK)
 530                 ret = nvmet_file_ns_enable(ns);
 531         if (ret)
 532                 goto out_unlock;
 533
 534         ret = nvmet_p2pmem_ns_enable(ns);
 535         if (ret)
 536                 goto out_dev_disable;
 537
 538         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 539                 nvmet_p2pmem_ns_add_p2p(ctrl, ns);
 540
 541         ret = percpu_ref_init(&ns->ref, nvmet_destroy_namespace,
 542                                 0, GFP_KERNEL);
 543         if (ret)
 544                 goto out_dev_put;
 545
 546         if (ns->nsid > subsys->max_nsid)
 547                 subsys->max_nsid = ns->nsid;
 548
 549         /*
 550          * The namespaces list needs to be sorted to simplify the implementation
 551          * of the Identify Namepace List subcommand.
 552          */
 553         if (list_empty(&subsys->namespaces)) {
 554                 list_add_tail_rcu(&ns->dev_link, &subsys->namespaces);
 555         } else {
 556                 struct nvmet_ns *old;
 557
 558                 list_for_each_entry_rcu(old, &subsys->namespaces, dev_link) {
 559                         BUG_ON(ns->nsid == old->nsid);
 560                         if (ns->nsid < old->nsid)
 561                                 break;
 562                 }
 563
 564                 list_add_tail_rcu(&ns->dev_link, &old->dev_link);
 565         }
 566         subsys->nr_namespaces++;
 567
 568         nvmet_ns_changed(subsys, ns->nsid);
 569         ns->enabled = true;
 570         ret = 0;
 571 out_unlock:
 572         mutex_unlock(&subsys->lock);
 573         return ret;
 574 out_dev_put:
 575         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 576                 pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
 577 out_dev_disable:
 578         nvmet_ns_dev_disable(ns);
 579         goto out_unlock;
 580 }
 581
 582 void nvmet_ns_disable(struct nvmet_ns *ns)
 583 {
 584         struct nvmet_subsys *subsys = ns->subsys;
 585         struct nvmet_ctrl *ctrl;
 586
 587         mutex_lock(&subsys->lock);
 588         if (!ns->enabled)
 589                 goto out_unlock;
 590
 591         ns->enabled = false;
 592         list_del_rcu(&ns->dev_link);
 593         if (ns->nsid == subsys->max_nsid)
 594                 subsys->max_nsid = nvmet_max_nsid(subsys);
 595
 596         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 597                 pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
 598
 599         mutex_unlock(&subsys->lock);
 600
 601         /*
 602          * Now that we removed the namespaces from the lookup list, we
 603          * can kill the per_cpu ref and wait for any remaining references
 604          * to be dropped, as well as a RCU grace period for anyone only
 605          * using the namepace under rcu_read_lock().  Note that we can't
 606          * use call_rcu here as we need to ensure the namespaces have
 607          * been fully destroyed before unloading the module.
 608          */
 609         percpu_ref_kill(&ns->ref);
 610         synchronize_rcu();
 611         wait_for_completion(&ns->disable_done);
 612         percpu_ref_exit(&ns->ref);
 613
 614         mutex_lock(&subsys->lock);
 615
 616         subsys->nr_namespaces--;
 617         nvmet_ns_changed(subsys, ns->nsid);
 618         nvmet_ns_dev_disable(ns);
 619 out_unlock:
 620         mutex_unlock(&subsys->lock);
 621 }
 622
 623 void nvmet_ns_free(struct nvmet_ns *ns)
 624 {
 625         nvmet_ns_disable(ns);
 626
 627         down_write(&nvmet_ana_sem);
 628         nvmet_ana_group_enabled[ns->anagrpid]--;
 629         up_write(&nvmet_ana_sem);
 630
 631         kfree(ns->device_path);
 632         kfree(ns);
 633 }
 634
 635 struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid)
 636 {
 637         struct nvmet_ns *ns;
 638
 639         ns = kzalloc(sizeof(*ns), GFP_KERNEL);
 640         if (!ns)
 641                 return NULL;
 642
 643         INIT_LIST_HEAD(&ns->dev_link);
 644         init_completion(&ns->disable_done);
 645
 646         ns->nsid = nsid;
 647         ns->subsys = subsys;
 648
 649         down_write(&nvmet_ana_sem);
 650         ns->anagrpid = NVMET_DEFAULT_ANA_GRPID;
 651         nvmet_ana_group_enabled[ns->anagrpid]++;
 652         up_write(&nvmet_ana_sem);
 653
 654         uuid_gen(&ns->uuid);
 655         ns->buffered_io = false;
 656
 657         return ns;
 658 }
 659
 660 static void nvmet_update_sq_head(struct nvmet_req *req)
 661 {
 662         if (req->sq->size) {
 663                 u32 old_sqhd, new_sqhd;
 664
 665                 do {
 666                         old_sqhd = req->sq->sqhd;
 667                         new_sqhd = (old_sqhd + 1) % req->sq->size;
 668                 } while (cmpxchg(&req->sq->sqhd, old_sqhd, new_sqhd) !=
 669                                         old_sqhd);
 670         }
 671         req->cqe->sq_head = cpu_to_le16(req->sq->sqhd & 0x0000FFFF);
 672 }
 673
 674 static void nvmet_set_error(struct nvmet_req *req, u16 status)
 675 {
 676         struct nvmet_ctrl *ctrl = req->sq->ctrl;
 677         struct nvme_error_slot *new_error_slot;
 678         unsigned long flags;
 679
 680         req->cqe->status = cpu_to_le16(status << 1);
 681
 682         if (!ctrl || req->error_loc == NVMET_NO_ERROR_LOC)
 683                 return;
 684
 685         spin_lock_irqsave(&ctrl->error_lock, flags);
 686         ctrl->err_counter++;
 687         new_error_slot =
 688                 &ctrl->slots[ctrl->err_counter % NVMET_ERROR_LOG_SLOTS];
 689
 690         new_error_slot->error_count = cpu_to_le64(ctrl->err_counter);
 691         new_error_slot->sqid = cpu_to_le16(req->sq->qid);
 692         new_error_slot->cmdid = cpu_to_le16(req->cmd->common.command_id);
 693         new_error_slot->status_field = cpu_to_le16(status << 1);
 694         new_error_slot->param_error_location = cpu_to_le16(req->error_loc);
 695         new_error_slot->lba = cpu_to_le64(req->error_slba);
 696         new_error_slot->nsid = req->cmd->common.nsid;
 697         spin_unlock_irqrestore(&ctrl->error_lock, flags);
 698
 699         /* set the more bit for this request */
 700         req->cqe->status |= cpu_to_le16(1 << 14);
 701 }
 702
 703 static void __nvmet_req_complete(struct nvmet_req *req, u16 status)
 704 {
 705         if (!req->sq->sqhd_disabled)
 706                 nvmet_update_sq_head(req);
 707         req->cqe->sq_id = cpu_to_le16(req->sq->qid);
 708         req->cqe->command_id = req->cmd->common.command_id;
 709
 710         if (unlikely(status))
 711                 nvmet_set_error(req, status);
 712
 713         trace_nvmet_req_complete(req);
 714
 715         if (req->ns)
 716                 nvmet_put_namespace(req->ns);
 717         req->ops->queue_response(req);
 718 }
 719
 720 void nvmet_req_complete(struct nvmet_req *req, u16 status)
 721 {
 722         __nvmet_req_complete(req, status);
 723         percpu_ref_put(&req->sq->ref);
 724 }
 725 EXPORT_SYMBOL_GPL(nvmet_req_complete);
 726
 727 void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq,
 728                 u16 qid, u16 size)
 729 {
 730         cq->qid = qid;
 731         cq->size = size;
 732
 733         ctrl->cqs[qid] = cq;
 734 }
 735
 736 void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq,
 737                 u16 qid, u16 size)
 738 {
 739         sq->sqhd = 0;
 740         sq->qid = qid;
 741         sq->size = size;
 742
 743         ctrl->sqs[qid] = sq;
 744 }
 745
 746 static void nvmet_confirm_sq(struct percpu_ref *ref)
 747 {
 748         struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref);
 749
 750         complete(&sq->confirm_done);
 751 }
 752
 753 void nvmet_sq_destroy(struct nvmet_sq *sq)
 754 {
 755         /*
 756          * If this is the admin queue, complete all AERs so that our
 757          * queue doesn't have outstanding requests on it.
 758          */
 759         if (sq->ctrl && sq->ctrl->sqs && sq->ctrl->sqs[0] == sq)
 760                 nvmet_async_events_free(sq->ctrl);
 761         percpu_ref_kill_and_confirm(&sq->ref, nvmet_confirm_sq);
 762         wait_for_completion(&sq->confirm_done);
 763         wait_for_completion(&sq->free_done);
 764         percpu_ref_exit(&sq->ref);
 765
 766         if (sq->ctrl) {
 767                 nvmet_ctrl_put(sq->ctrl);
 768                 sq->ctrl = NULL; /* allows reusing the queue later */
 769         }
 770 }
 771 EXPORT_SYMBOL_GPL(nvmet_sq_destroy);
 772
 773 static void nvmet_sq_free(struct percpu_ref *ref)
 774 {
 775         struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref);
 776
 777         complete(&sq->free_done);
 778 }
 779
 780 int nvmet_sq_init(struct nvmet_sq *sq)
 781 {
 782         int ret;
 783
 784         ret = percpu_ref_init(&sq->ref, nvmet_sq_free, 0, GFP_KERNEL);
 785         if (ret) {
 786                 pr_err("percpu_ref init failed!\n");
 787                 return ret;
 788         }
 789         init_completion(&sq->free_done);
 790         init_completion(&sq->confirm_done);
 791
 792         return 0;
 793 }
 794 EXPORT_SYMBOL_GPL(nvmet_sq_init);
 795
 796 static inline u16 nvmet_check_ana_state(struct nvmet_port *port,
 797                 struct nvmet_ns *ns)
 798 {
 799         enum nvme_ana_state state = port->ana_state[ns->anagrpid];
 800
 801         if (unlikely(state == NVME_ANA_INACCESSIBLE))
 802                 return NVME_SC_ANA_INACCESSIBLE;
 803         if (unlikely(state == NVME_ANA_PERSISTENT_LOSS))
 804                 return NVME_SC_ANA_PERSISTENT_LOSS;
 805         if (unlikely(state == NVME_ANA_CHANGE))
 806                 return NVME_SC_ANA_TRANSITION;
 807         return 0;
 808 }
 809
 810 static inline u16 nvmet_io_cmd_check_access(struct nvmet_req *req)
 811 {
 812         if (unlikely(req->ns->readonly)) {
 813                 switch (req->cmd->common.opcode) {
 814                 case nvme_cmd_read:
 815                 case nvme_cmd_flush:
 816                         break;
 817                 default:
 818                         return NVME_SC_NS_WRITE_PROTECTED;
 819                 }
 820         }
 821
 822         return 0;
 823 }
 824
 825 static u16 nvmet_parse_io_cmd(struct nvmet_req *req)
 826 {
 827         struct nvme_command *cmd = req->cmd;
 828         u16 ret;
 829
 830         ret = nvmet_check_ctrl_status(req, cmd);
 831         if (unlikely(ret))
 832                 return ret;
 833
 834         req->ns = nvmet_find_namespace(req->sq->ctrl, cmd->rw.nsid);
 835         if (unlikely(!req->ns)) {
 836                 req->error_loc = offsetof(struct nvme_common_command, nsid);
 837                 return NVME_SC_INVALID_NS | NVME_SC_DNR;
 838         }
 839         ret = nvmet_check_ana_state(req->port, req->ns);
 840         if (unlikely(ret)) {
 841                 req->error_loc = offsetof(struct nvme_common_command, nsid);
 842                 return ret;
 843         }
 844         ret = nvmet_io_cmd_check_access(req);
 845         if (unlikely(ret)) {
 846                 req->error_loc = offsetof(struct nvme_common_command, nsid);
 847                 return ret;
 848         }
 849
 850         if (req->ns->file)
 851                 return nvmet_file_parse_io_cmd(req);
 852         else
 853                 return nvmet_bdev_parse_io_cmd(req);
 854 }
 855
 856 bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
 857                 struct nvmet_sq *sq, const struct nvmet_fabrics_ops *ops)
 858 {
 859         u8 flags = req->cmd->common.flags;
 860         u16 status;
 861
 862         req->cq = cq;
 863         req->sq = sq;
 864         req->ops = ops;
 865         req->sg = NULL;
 866         req->sg_cnt = 0;
 867         req->transfer_len = 0;
 868         req->cqe->status = 0;
 869         req->cqe->sq_head = 0;
 870         req->ns = NULL;
 871         req->error_loc = NVMET_NO_ERROR_LOC;
 872         req->error_slba = 0;
 873
 874         trace_nvmet_req_init(req, req->cmd);
 875
 876         /* no support for fused commands yet */
 877         if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) {
 878                 req->error_loc = offsetof(struct nvme_common_command, flags);
 879                 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 880                 goto fail;
 881         }
 882
 883         /*
 884          * For fabrics, PSDT field shall describe metadata pointer (MPTR) that
 885          * contains an address of a single contiguous physical buffer that is
 886          * byte aligned.
 887          */
 888         if (unlikely((flags & NVME_CMD_SGL_ALL) != NVME_CMD_SGL_METABUF)) {
 889                 req->error_loc = offsetof(struct nvme_common_command, flags);
 890                 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 891                 goto fail;
 892         }
 893
 894         if (unlikely(!req->sq->ctrl))
 895                 /* will return an error for any Non-connect command: */
 896                 status = nvmet_parse_connect_cmd(req);
 897         else if (likely(req->sq->qid != 0))
 898                 status = nvmet_parse_io_cmd(req);
 899         else if (nvme_is_fabrics(req->cmd))
 900                 status = nvmet_parse_fabrics_cmd(req);
 901         else if (req->sq->ctrl->subsys->type == NVME_NQN_DISC)
 902                 status = nvmet_parse_discovery_cmd(req);
 903         else
 904                 status = nvmet_parse_admin_cmd(req);
 905
 906         if (status)
 907                 goto fail;
 908
 909         if (unlikely(!percpu_ref_tryget_live(&sq->ref))) {
 910                 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 911                 goto fail;
 912         }
 913
 914         if (sq->ctrl)
 915                 sq->ctrl->cmd_seen = true;
 916
 917         return true;
 918
 919 fail:
 920         __nvmet_req_complete(req, status);
 921         return false;
 922 }
 923 EXPORT_SYMBOL_GPL(nvmet_req_init);
 924
 925 void nvmet_req_uninit(struct nvmet_req *req)
 926 {
 927         percpu_ref_put(&req->sq->ref);
 928         if (req->ns)
 929                 nvmet_put_namespace(req->ns);
 930 }
 931 EXPORT_SYMBOL_GPL(nvmet_req_uninit);
 932
 933 void nvmet_req_execute(struct nvmet_req *req)
 934 {
 935         if (unlikely(req->data_len != req->transfer_len)) {
 936                 req->error_loc = offsetof(struct nvme_common_command, dptr);
 937                 nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR);
 938         } else
 939                 req->execute(req);
 940 }
 941 EXPORT_SYMBOL_GPL(nvmet_req_execute);
 942
 943 int nvmet_req_alloc_sgl(struct nvmet_req *req)
 944 {
 945         struct pci_dev *p2p_dev = NULL;
 946
 947         if (IS_ENABLED(CONFIG_PCI_P2PDMA)) {
 948                 if (req->sq->ctrl && req->ns)
 949                         p2p_dev = radix_tree_lookup(&req->sq->ctrl->p2p_ns_map,
 950                                                     req->ns->nsid);
 951
 952                 req->p2p_dev = NULL;
 953                 if (req->sq->qid && p2p_dev) {
 954                         req->sg = pci_p2pmem_alloc_sgl(p2p_dev, &req->sg_cnt,
 955                                                        req->transfer_len);
 956                         if (req->sg) {
 957                                 req->p2p_dev = p2p_dev;
 958                                 return 0;
 959                         }
 960                 }
 961
 962                 /*
 963                  * If no P2P memory was available we fallback to using
 964                  * regular memory
 965                  */
 966         }
 967
 968         req->sg = sgl_alloc(req->transfer_len, GFP_KERNEL, &req->sg_cnt);
 969         if (!req->sg)
 970                 return -ENOMEM;
 971
 972         return 0;
 973 }
 974 EXPORT_SYMBOL_GPL(nvmet_req_alloc_sgl);
 975
 976 void nvmet_req_free_sgl(struct nvmet_req *req)
 977 {
 978         if (req->p2p_dev)
 979                 pci_p2pmem_free_sgl(req->p2p_dev, req->sg);
 980         else
 981                 sgl_free(req->sg);
 982
 983         req->sg = NULL;
 984         req->sg_cnt = 0;
 985 }
 986 EXPORT_SYMBOL_GPL(nvmet_req_free_sgl);
 987
 988 static inline bool nvmet_cc_en(u32 cc)
 989 {
 990         return (cc >> NVME_CC_EN_SHIFT) & 0x1;
 991 }
 992
 993 static inline u8 nvmet_cc_css(u32 cc)
 994 {
 995         return (cc >> NVME_CC_CSS_SHIFT) & 0x7;
 996 }
 997
 998 static inline u8 nvmet_cc_mps(u32 cc)
 999 {
1000         return (cc >> NVME_CC_MPS_SHIFT) & 0xf;
1001 }
1002
1003 static inline u8 nvmet_cc_ams(u32 cc)
1004 {
1005         return (cc >> NVME_CC_AMS_SHIFT) & 0x7;
1006 }
1007
1008 static inline u8 nvmet_cc_shn(u32 cc)
1009 {
1010         return (cc >> NVME_CC_SHN_SHIFT) & 0x3;
1011 }
1012
1013 static inline u8 nvmet_cc_iosqes(u32 cc)
1014 {
1015         return (cc >> NVME_CC_IOSQES_SHIFT) & 0xf;
1016 }
1017
1018 static inline u8 nvmet_cc_iocqes(u32 cc)
1019 {
1020         return (cc >> NVME_CC_IOCQES_SHIFT) & 0xf;
1021 }
1022
1023 static void nvmet_start_ctrl(struct nvmet_ctrl *ctrl)
1024 {
1025         lockdep_assert_held(&ctrl->lock);
1026
1027         if (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES ||
1028             nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES ||
1029             nvmet_cc_mps(ctrl->cc) != 0 ||
1030             nvmet_cc_ams(ctrl->cc) != 0 ||
1031             nvmet_cc_css(ctrl->cc) != 0) {
1032                 ctrl->csts = NVME_CSTS_CFS;
1033                 return;
1034         }
1035
1036         ctrl->csts = NVME_CSTS_RDY;
1037
1038         /*
1039          * Controllers that are not yet enabled should not really enforce the
1040          * keep alive timeout, but we still want to track a timeout and cleanup
1041          * in case a host died before it enabled the controller.  Hence, simply
1042          * reset the keep alive timer when the controller is enabled.
1043          */
1044         mod_delayed_work(system_wq, &ctrl->ka_work, ctrl->kato * HZ);
1045 }
1046
1047 static void nvmet_clear_ctrl(struct nvmet_ctrl *ctrl)
1048 {
1049         lockdep_assert_held(&ctrl->lock);
1050
1051         /* XXX: tear down queues? */
1052         ctrl->csts &= ~NVME_CSTS_RDY;
1053         ctrl->cc = 0;
1054 }
1055
1056 void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new)
1057 {
1058         u32 old;
1059
1060         mutex_lock(&ctrl->lock);
1061         old = ctrl->cc;
1062         ctrl->cc = new;
1063
1064         if (nvmet_cc_en(new) && !nvmet_cc_en(old))
1065                 nvmet_start_ctrl(ctrl);
1066         if (!nvmet_cc_en(new) && nvmet_cc_en(old))
1067                 nvmet_clear_ctrl(ctrl);
1068         if (nvmet_cc_shn(new) && !nvmet_cc_shn(old)) {
1069                 nvmet_clear_ctrl(ctrl);
1070                 ctrl->csts |= NVME_CSTS_SHST_CMPLT;
1071         }
1072         if (!nvmet_cc_shn(new) && nvmet_cc_shn(old))
1073                 ctrl->csts &= ~NVME_CSTS_SHST_CMPLT;
1074         mutex_unlock(&ctrl->lock);
1075 }
1076
1077 static void nvmet_init_cap(struct nvmet_ctrl *ctrl)
1078 {
1079         /* command sets supported: NVMe command set: */
1080         ctrl->cap = (1ULL << 37);
1081         /* CC.EN timeout in 500msec units: */
1082         ctrl->cap |= (15ULL << 24);
1083         /* maximum queue entries supported: */
1084         ctrl->cap |= NVMET_QUEUE_SIZE - 1;
1085 }
1086
1087 u16 nvmet_ctrl_find_get(const char *subsysnqn, const char *hostnqn, u16 cntlid,
1088                 struct nvmet_req *req, struct nvmet_ctrl **ret)
1089 {
1090         struct nvmet_subsys *subsys;
1091         struct nvmet_ctrl *ctrl;
1092         u16 status = 0;
1093
1094         subsys = nvmet_find_get_subsys(req->port, subsysnqn);
1095         if (!subsys) {
1096                 pr_warn("connect request for invalid subsystem %s!\n",
1097                         subsysnqn);
1098                 req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn);
1099                 return NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1100         }
1101
1102         mutex_lock(&subsys->lock);
1103         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
1104                 if (ctrl->cntlid == cntlid) {
1105                         if (strncmp(hostnqn, ctrl->hostnqn, NVMF_NQN_SIZE)) {
1106                                 pr_warn("hostnqn mismatch.\n");
1107                                 continue;
1108                         }
1109                         if (!kref_get_unless_zero(&ctrl->ref))
1110                                 continue;
1111
1112                         *ret = ctrl;
1113                         goto out;
1114                 }
1115         }
1116
1117         pr_warn("could not find controller %d for subsys %s / host %s\n",
1118                 cntlid, subsysnqn, hostnqn);
1119         req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(cntlid);
1120         status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1121
1122 out:
1123         mutex_unlock(&subsys->lock);
1124         nvmet_subsys_put(subsys);
1125         return status;
1126 }
1127
1128 u16 nvmet_check_ctrl_status(struct nvmet_req *req, struct nvme_command *cmd)
1129 {
1130         if (unlikely(!(req->sq->ctrl->cc & NVME_CC_ENABLE))) {
1131                 pr_err("got cmd %d while CC.EN == 0 on qid = %d\n",
1132                        cmd->common.opcode, req->sq->qid);
1133                 return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
1134         }
1135
1136         if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
1137                 pr_err("got cmd %d while CSTS.RDY == 0 on qid = %d\n",
1138                        cmd->common.opcode, req->sq->qid);
1139                 return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
1140         }
1141         return 0;
1142 }
1143
1144 bool nvmet_host_allowed(struct nvmet_subsys *subsys, const char *hostnqn)
1145 {
1146         struct nvmet_host_link *p;
1147
1148         lockdep_assert_held(&nvmet_config_sem);
1149
1150         if (subsys->allow_any_host)
1151                 return true;
1152
1153         if (subsys->type == NVME_NQN_DISC) /* allow all access to disc subsys */
1154                 return true;
1155
1156         list_for_each_entry(p, &subsys->hosts, entry) {
1157                 if (!strcmp(nvmet_host_name(p->host), hostnqn))
1158                         return true;
1159         }
1160
1161         return false;
1162 }
1163
1164 /*
1165  * Note: ctrl->subsys->lock should be held when calling this function
1166  */
1167 static void nvmet_setup_p2p_ns_map(struct nvmet_ctrl *ctrl,
1168                 struct nvmet_req *req)
1169 {
1170         struct nvmet_ns *ns;
1171
1172         if (!req->p2p_client)
1173                 return;
1174
1175         ctrl->p2p_client = get_device(req->p2p_client);
1176
1177         list_for_each_entry_rcu(ns, &ctrl->subsys->namespaces, dev_link)
1178                 nvmet_p2pmem_ns_add_p2p(ctrl, ns);
1179 }
1180
1181 /*
1182  * Note: ctrl->subsys->lock should be held when calling this function
1183  */
1184 static void nvmet_release_p2p_ns_map(struct nvmet_ctrl *ctrl)
1185 {
1186         struct radix_tree_iter iter;
1187         void __rcu **slot;
1188
1189         radix_tree_for_each_slot(slot, &ctrl->p2p_ns_map, &iter, 0)
1190                 pci_dev_put(radix_tree_deref_slot(slot));
1191
1192         put_device(ctrl->p2p_client);
1193 }
1194
1195 static void nvmet_fatal_error_handler(struct work_struct *work)
1196 {
1197         struct nvmet_ctrl *ctrl =
1198                         container_of(work, struct nvmet_ctrl, fatal_err_work);
1199
1200         pr_err("ctrl %d fatal error occurred!\n", ctrl->cntlid);
1201         ctrl->ops->delete_ctrl(ctrl);
1202 }
1203
1204 u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
1205                 struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp)
1206 {
1207         struct nvmet_subsys *subsys;
1208         struct nvmet_ctrl *ctrl;
1209         int ret;
1210         u16 status;
1211
1212         status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1213         subsys = nvmet_find_get_subsys(req->port, subsysnqn);
1214         if (!subsys) {
1215                 pr_warn("connect request for invalid subsystem %s!\n",
1216                         subsysnqn);
1217                 req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn);
1218                 goto out;
1219         }
1220
1221         status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1222         down_read(&nvmet_config_sem);
1223         if (!nvmet_host_allowed(subsys, hostnqn)) {
1224                 pr_info("connect by host %s for subsystem %s not allowed\n",
1225                         hostnqn, subsysnqn);
1226                 req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(hostnqn);
1227                 up_read(&nvmet_config_sem);
1228                 status = NVME_SC_CONNECT_INVALID_HOST | NVME_SC_DNR;
1229                 goto out_put_subsystem;
1230         }
1231         up_read(&nvmet_config_sem);
1232
1233         status = NVME_SC_INTERNAL;
1234         ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
1235         if (!ctrl)
1236                 goto out_put_subsystem;
1237         mutex_init(&ctrl->lock);
1238
1239         nvmet_init_cap(ctrl);
1240
1241         ctrl->port = req->port;
1242
1243         INIT_WORK(&ctrl->async_event_work, nvmet_async_event_work);
1244         INIT_LIST_HEAD(&ctrl->async_events);
1245         INIT_RADIX_TREE(&ctrl->p2p_ns_map, GFP_KERNEL);
1246         INIT_WORK(&ctrl->fatal_err_work, nvmet_fatal_error_handler);
1247
1248         memcpy(ctrl->subsysnqn, subsysnqn, NVMF_NQN_SIZE);
1249         memcpy(ctrl->hostnqn, hostnqn, NVMF_NQN_SIZE);
1250
1251         kref_init(&ctrl->ref);
1252         ctrl->subsys = subsys;
1253         WRITE_ONCE(ctrl->aen_enabled, NVMET_AEN_CFG_OPTIONAL);
1254
1255         ctrl->changed_ns_list = kmalloc_array(NVME_MAX_CHANGED_NAMESPACES,
1256                         sizeof(__le32), GFP_KERNEL);
1257         if (!ctrl->changed_ns_list)
1258                 goto out_free_ctrl;
1259
1260         ctrl->cqs = kcalloc(subsys->max_qid + 1,
1261                         sizeof(struct nvmet_cq *),
1262                         GFP_KERNEL);
1263         if (!ctrl->cqs)
1264                 goto out_free_changed_ns_list;
1265
1266         ctrl->sqs = kcalloc(subsys->max_qid + 1,
1267                         sizeof(struct nvmet_sq *),
1268                         GFP_KERNEL);
1269         if (!ctrl->sqs)
1270                 goto out_free_cqs;
1271
1272         ret = ida_simple_get(&cntlid_ida,
1273                              NVME_CNTLID_MIN, NVME_CNTLID_MAX,
1274                              GFP_KERNEL);
1275         if (ret < 0) {
1276                 status = NVME_SC_CONNECT_CTRL_BUSY | NVME_SC_DNR;
1277                 goto out_free_sqs;
1278         }
1279         ctrl->cntlid = ret;
1280
1281         ctrl->ops = req->ops;
1282
1283         /*
1284          * Discovery controllers may use some arbitrary high value
1285          * in order to cleanup stale discovery sessions
1286          */
1287         if ((ctrl->subsys->type == NVME_NQN_DISC) && !kato)
1288                 kato = NVMET_DISC_KATO_MS;
1289
1290         /* keep-alive timeout in seconds */
1291         ctrl->kato = DIV_ROUND_UP(kato, 1000);
1292
1293         ctrl->err_counter = 0;
1294         spin_lock_init(&ctrl->error_lock);
1295
1296         nvmet_start_keep_alive_timer(ctrl);
1297
1298         mutex_lock(&subsys->lock);
1299         list_add_tail(&ctrl->subsys_entry, &subsys->ctrls);
1300         nvmet_setup_p2p_ns_map(ctrl, req);
1301         mutex_unlock(&subsys->lock);
1302
1303         *ctrlp = ctrl;
1304         return 0;
1305
1306 out_free_sqs:
1307         kfree(ctrl->sqs);
1308 out_free_cqs:
1309         kfree(ctrl->cqs);
1310 out_free_changed_ns_list:
1311         kfree(ctrl->changed_ns_list);
1312 out_free_ctrl:
1313         kfree(ctrl);
1314 out_put_subsystem:
1315         nvmet_subsys_put(subsys);
1316 out:
1317         return status;
1318 }
1319
1320 static void nvmet_ctrl_free(struct kref *ref)
1321 {
1322         struct nvmet_ctrl *ctrl = container_of(ref, struct nvmet_ctrl, ref);
1323         struct nvmet_subsys *subsys = ctrl->subsys;
1324
1325         mutex_lock(&subsys->lock);
1326         nvmet_release_p2p_ns_map(ctrl);
1327         list_del(&ctrl->subsys_entry);
1328         mutex_unlock(&subsys->lock);
1329
1330         nvmet_stop_keep_alive_timer(ctrl);
1331
1332         flush_work(&ctrl->async_event_work);
1333         cancel_work_sync(&ctrl->fatal_err_work);
1334
1335         ida_simple_remove(&cntlid_ida, ctrl->cntlid);
1336
1337         kfree(ctrl->sqs);
1338         kfree(ctrl->cqs);
1339         kfree(ctrl->changed_ns_list);
1340         kfree(ctrl);
1341
1342         nvmet_subsys_put(subsys);
1343 }
1344
1345 void nvmet_ctrl_put(struct nvmet_ctrl *ctrl)
1346 {
1347         kref_put(&ctrl->ref, nvmet_ctrl_free);
1348 }
1349
1350 void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl)
1351 {
1352         mutex_lock(&ctrl->lock);
1353         if (!(ctrl->csts & NVME_CSTS_CFS)) {
1354                 ctrl->csts |= NVME_CSTS_CFS;
1355                 schedule_work(&ctrl->fatal_err_work);
1356         }
1357         mutex_unlock(&ctrl->lock);
1358 }
1359 EXPORT_SYMBOL_GPL(nvmet_ctrl_fatal_error);
1360
1361 static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
1362                 const char *subsysnqn)
1363 {
1364         struct nvmet_subsys_link *p;
1365
1366         if (!port)
1367                 return NULL;
1368
1369         if (!strcmp(NVME_DISC_SUBSYS_NAME, subsysnqn)) {
1370                 if (!kref_get_unless_zero(&nvmet_disc_subsys->ref))
1371                         return NULL;
1372                 return nvmet_disc_subsys;
1373         }
1374
1375         down_read(&nvmet_config_sem);
1376         list_for_each_entry(p, &port->subsystems, entry) {
1377                 if (!strncmp(p->subsys->subsysnqn, subsysnqn,
1378                                 NVMF_NQN_SIZE)) {
1379                         if (!kref_get_unless_zero(&p->subsys->ref))
1380                                 break;
1381                         up_read(&nvmet_config_sem);
1382                         return p->subsys;
1383                 }
1384         }
1385         up_read(&nvmet_config_sem);
1386         return NULL;
1387 }
1388
1389 struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
1390                 enum nvme_subsys_type type)
1391 {
1392         struct nvmet_subsys *subsys;
1393
1394         subsys = kzalloc(sizeof(*subsys), GFP_KERNEL);
1395         if (!subsys)
1396                 return ERR_PTR(-ENOMEM);
1397
1398         subsys->ver = NVME_VS(1, 3, 0); /* NVMe 1.3.0 */
1399         /* generate a random serial number as our controllers are ephemeral: */
1400         get_random_bytes(&subsys->serial, sizeof(subsys->serial));
1401
1402         switch (type) {
1403         case NVME_NQN_NVME:
1404                 subsys->max_qid = NVMET_NR_QUEUES;
1405                 break;
1406         case NVME_NQN_DISC:
1407                 subsys->max_qid = 0;
1408                 break;
1409         default:
1410                 pr_err("%s: Unknown Subsystem type - %d\n", __func__, type);
1411                 kfree(subsys);
1412                 return ERR_PTR(-EINVAL);
1413         }
1414         subsys->type = type;
1415         subsys->subsysnqn = kstrndup(subsysnqn, NVMF_NQN_SIZE,
1416                         GFP_KERNEL);
1417         if (!subsys->subsysnqn) {
1418                 kfree(subsys);
1419                 return ERR_PTR(-ENOMEM);
1420         }
1421
1422         kref_init(&subsys->ref);
1423
1424         mutex_init(&subsys->lock);
1425         INIT_LIST_HEAD(&subsys->namespaces);
1426         INIT_LIST_HEAD(&subsys->ctrls);
1427         INIT_LIST_HEAD(&subsys->hosts);
1428
1429         return subsys;
1430 }
1431
1432 static void nvmet_subsys_free(struct kref *ref)
1433 {
1434         struct nvmet_subsys *subsys =
1435                 container_of(ref, struct nvmet_subsys, ref);
1436
1437         WARN_ON_ONCE(!list_empty(&subsys->namespaces));
1438
1439         kfree(subsys->subsysnqn);
1440         kfree(subsys);
1441 }
1442
1443 void nvmet_subsys_del_ctrls(struct nvmet_subsys *subsys)
1444 {
1445         struct nvmet_ctrl *ctrl;
1446
1447         mutex_lock(&subsys->lock);
1448         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
1449                 ctrl->ops->delete_ctrl(ctrl);
1450         mutex_unlock(&subsys->lock);
1451 }
1452
1453 void nvmet_subsys_put(struct nvmet_subsys *subsys)
1454 {
1455         kref_put(&subsys->ref, nvmet_subsys_free);
1456 }
1457
1458 static int __init nvmet_init(void)
1459 {
1460         int error;
1461
1462         nvmet_ana_group_enabled[NVMET_DEFAULT_ANA_GRPID] = 1;
1463
1464         buffered_io_wq = alloc_workqueue("nvmet-buffered-io-wq",
1465                         WQ_MEM_RECLAIM, 0);
1466         if (!buffered_io_wq) {
1467                 error = -ENOMEM;
1468                 goto out;
1469         }
1470
1471         error = nvmet_init_discovery();
1472         if (error)
1473                 goto out_free_work_queue;
1474
1475         error = nvmet_init_configfs();
1476         if (error)
1477                 goto out_exit_discovery;
1478         return 0;
1479
1480 out_exit_discovery:
1481         nvmet_exit_discovery();
1482 out_free_work_queue:
1483         destroy_workqueue(buffered_io_wq);
1484 out:
1485         return error;
1486 }
1487
1488 static void __exit nvmet_exit(void)
1489 {
1490         nvmet_exit_configfs();
1491         nvmet_exit_discovery();
1492         ida_destroy(&cntlid_ida);
1493         destroy_workqueue(buffered_io_wq);
1494
1495         BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_entry) != 1024);
1496         BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_hdr) != 1024);
1497 }
1498
1499 module_init(nvmet_init);
1500 module_exit(nvmet_exit);
1501
1502 MODULE_LICENSE("GPL v2");