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                 fallthrough;
  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         unsigned long nsid = 0;
 119         struct nvmet_ns *cur;
 120         unsigned long idx;
 121
 122         xa_for_each(&subsys->namespaces, idx, cur)
 123                 nsid = cur->nsid;
 124
 125         return nsid;
 126 }
 127
 128 static u32 nvmet_async_event_result(struct nvmet_async_event *aen)
 129 {
 130         return aen->event_type | (aen->event_info << 8) | (aen->log_page << 16);
 131 }
 132
 133 static void nvmet_async_events_failall(struct nvmet_ctrl *ctrl)
 134 {
 135         u16 status = NVME_SC_INTERNAL | NVME_SC_DNR;
 136         struct nvmet_req *req;
 137
 138         mutex_lock(&ctrl->lock);
 139         while (ctrl->nr_async_event_cmds) {
 140                 req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds];
 141                 mutex_unlock(&ctrl->lock);
 142                 nvmet_req_complete(req, status);
 143                 mutex_lock(&ctrl->lock);
 144         }
 145         mutex_unlock(&ctrl->lock);
 146 }
 147
 148 static void nvmet_async_events_process(struct nvmet_ctrl *ctrl)
 149 {
 150         struct nvmet_async_event *aen;
 151         struct nvmet_req *req;
 152
 153         mutex_lock(&ctrl->lock);
 154         while (ctrl->nr_async_event_cmds && !list_empty(&ctrl->async_events)) {
 155                 aen = list_first_entry(&ctrl->async_events,
 156                                        struct nvmet_async_event, entry);
 157                 req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds];
 158                 nvmet_set_result(req, nvmet_async_event_result(aen));
 159
 160                 list_del(&aen->entry);
 161                 kfree(aen);
 162
 163                 mutex_unlock(&ctrl->lock);
 164                 trace_nvmet_async_event(ctrl, req->cqe->result.u32);
 165                 nvmet_req_complete(req, 0);
 166                 mutex_lock(&ctrl->lock);
 167         }
 168         mutex_unlock(&ctrl->lock);
 169 }
 170
 171 static void nvmet_async_events_free(struct nvmet_ctrl *ctrl)
 172 {
 173         struct nvmet_async_event *aen, *tmp;
 174
 175         mutex_lock(&ctrl->lock);
 176         list_for_each_entry_safe(aen, tmp, &ctrl->async_events, entry) {
 177                 list_del(&aen->entry);
 178                 kfree(aen);
 179         }
 180         mutex_unlock(&ctrl->lock);
 181 }
 182
 183 static void nvmet_async_event_work(struct work_struct *work)
 184 {
 185         struct nvmet_ctrl *ctrl =
 186                 container_of(work, struct nvmet_ctrl, async_event_work);
 187
 188         nvmet_async_events_process(ctrl);
 189 }
 190
 191 void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type,
 192                 u8 event_info, u8 log_page)
 193 {
 194         struct nvmet_async_event *aen;
 195
 196         aen = kmalloc(sizeof(*aen), GFP_KERNEL);
 197         if (!aen)
 198                 return;
 199
 200         aen->event_type = event_type;
 201         aen->event_info = event_info;
 202         aen->log_page = log_page;
 203
 204         mutex_lock(&ctrl->lock);
 205         list_add_tail(&aen->entry, &ctrl->async_events);
 206         mutex_unlock(&ctrl->lock);
 207
 208         schedule_work(&ctrl->async_event_work);
 209 }
 210
 211 static void nvmet_add_to_changed_ns_log(struct nvmet_ctrl *ctrl, __le32 nsid)
 212 {
 213         u32 i;
 214
 215         mutex_lock(&ctrl->lock);
 216         if (ctrl->nr_changed_ns > NVME_MAX_CHANGED_NAMESPACES)
 217                 goto out_unlock;
 218
 219         for (i = 0; i < ctrl->nr_changed_ns; i++) {
 220                 if (ctrl->changed_ns_list[i] == nsid)
 221                         goto out_unlock;
 222         }
 223
 224         if (ctrl->nr_changed_ns == NVME_MAX_CHANGED_NAMESPACES) {
 225                 ctrl->changed_ns_list[0] = cpu_to_le32(0xffffffff);
 226                 ctrl->nr_changed_ns = U32_MAX;
 227                 goto out_unlock;
 228         }
 229
 230         ctrl->changed_ns_list[ctrl->nr_changed_ns++] = nsid;
 231 out_unlock:
 232         mutex_unlock(&ctrl->lock);
 233 }
 234
 235 void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid)
 236 {
 237         struct nvmet_ctrl *ctrl;
 238
 239         lockdep_assert_held(&subsys->lock);
 240
 241         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
 242                 nvmet_add_to_changed_ns_log(ctrl, cpu_to_le32(nsid));
 243                 if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_NS_ATTR))
 244                         continue;
 245                 nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE,
 246                                 NVME_AER_NOTICE_NS_CHANGED,
 247                                 NVME_LOG_CHANGED_NS);
 248         }
 249 }
 250
 251 void nvmet_send_ana_event(struct nvmet_subsys *subsys,
 252                 struct nvmet_port *port)
 253 {
 254         struct nvmet_ctrl *ctrl;
 255
 256         mutex_lock(&subsys->lock);
 257         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
 258                 if (port && ctrl->port != port)
 259                         continue;
 260                 if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_ANA_CHANGE))
 261                         continue;
 262                 nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE,
 263                                 NVME_AER_NOTICE_ANA, NVME_LOG_ANA);
 264         }
 265         mutex_unlock(&subsys->lock);
 266 }
 267
 268 void nvmet_port_send_ana_event(struct nvmet_port *port)
 269 {
 270         struct nvmet_subsys_link *p;
 271
 272         down_read(&nvmet_config_sem);
 273         list_for_each_entry(p, &port->subsystems, entry)
 274                 nvmet_send_ana_event(p->subsys, port);
 275         up_read(&nvmet_config_sem);
 276 }
 277
 278 int nvmet_register_transport(const struct nvmet_fabrics_ops *ops)
 279 {
 280         int ret = 0;
 281
 282         down_write(&nvmet_config_sem);
 283         if (nvmet_transports[ops->type])
 284                 ret = -EINVAL;
 285         else
 286                 nvmet_transports[ops->type] = ops;
 287         up_write(&nvmet_config_sem);
 288
 289         return ret;
 290 }
 291 EXPORT_SYMBOL_GPL(nvmet_register_transport);
 292
 293 void nvmet_unregister_transport(const struct nvmet_fabrics_ops *ops)
 294 {
 295         down_write(&nvmet_config_sem);
 296         nvmet_transports[ops->type] = NULL;
 297         up_write(&nvmet_config_sem);
 298 }
 299 EXPORT_SYMBOL_GPL(nvmet_unregister_transport);
 300
 301 void nvmet_port_del_ctrls(struct nvmet_port *port, struct nvmet_subsys *subsys)
 302 {
 303         struct nvmet_ctrl *ctrl;
 304
 305         mutex_lock(&subsys->lock);
 306         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
 307                 if (ctrl->port == port)
 308                         ctrl->ops->delete_ctrl(ctrl);
 309         }
 310         mutex_unlock(&subsys->lock);
 311 }
 312
 313 int nvmet_enable_port(struct nvmet_port *port)
 314 {
 315         const struct nvmet_fabrics_ops *ops;
 316         int ret;
 317
 318         lockdep_assert_held(&nvmet_config_sem);
 319
 320         ops = nvmet_transports[port->disc_addr.trtype];
 321         if (!ops) {
 322                 up_write(&nvmet_config_sem);
 323                 request_module("nvmet-transport-%d", port->disc_addr.trtype);
 324                 down_write(&nvmet_config_sem);
 325                 ops = nvmet_transports[port->disc_addr.trtype];
 326                 if (!ops) {
 327                         pr_err("transport type %d not supported\n",
 328                                 port->disc_addr.trtype);
 329                         return -EINVAL;
 330                 }
 331         }
 332
 333         if (!try_module_get(ops->owner))
 334                 return -EINVAL;
 335
 336         /*
 337          * If the user requested PI support and the transport isn't pi capable,
 338          * don't enable the port.
 339          */
 340         if (port->pi_enable && !(ops->flags & NVMF_METADATA_SUPPORTED)) {
 341                 pr_err("T10-PI is not supported by transport type %d\n",
 342                        port->disc_addr.trtype);
 343                 ret = -EINVAL;
 344                 goto out_put;
 345         }
 346
 347         ret = ops->add_port(port);
 348         if (ret)
 349                 goto out_put;
 350
 351         /* If the transport didn't set inline_data_size, then disable it. */
 352         if (port->inline_data_size < 0)
 353                 port->inline_data_size = 0;
 354
 355         port->enabled = true;
 356         port->tr_ops = ops;
 357         return 0;
 358
 359 out_put:
 360         module_put(ops->owner);
 361         return ret;
 362 }
 363
 364 void nvmet_disable_port(struct nvmet_port *port)
 365 {
 366         const struct nvmet_fabrics_ops *ops;
 367
 368         lockdep_assert_held(&nvmet_config_sem);
 369
 370         port->enabled = false;
 371         port->tr_ops = NULL;
 372
 373         ops = nvmet_transports[port->disc_addr.trtype];
 374         ops->remove_port(port);
 375         module_put(ops->owner);
 376 }
 377
 378 static void nvmet_keep_alive_timer(struct work_struct *work)
 379 {
 380         struct nvmet_ctrl *ctrl = container_of(to_delayed_work(work),
 381                         struct nvmet_ctrl, ka_work);
 382         bool cmd_seen = ctrl->cmd_seen;
 383
 384         ctrl->cmd_seen = false;
 385         if (cmd_seen) {
 386                 pr_debug("ctrl %d reschedule traffic based keep-alive timer\n",
 387                         ctrl->cntlid);
 388                 schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
 389                 return;
 390         }
 391
 392         pr_err("ctrl %d keep-alive timer (%d seconds) expired!\n",
 393                 ctrl->cntlid, ctrl->kato);
 394
 395         nvmet_ctrl_fatal_error(ctrl);
 396 }
 397
 398 void nvmet_start_keep_alive_timer(struct nvmet_ctrl *ctrl)
 399 {
 400         if (unlikely(ctrl->kato == 0))
 401                 return;
 402
 403         pr_debug("ctrl %d start keep-alive timer for %d secs\n",
 404                 ctrl->cntlid, ctrl->kato);
 405
 406         INIT_DELAYED_WORK(&ctrl->ka_work, nvmet_keep_alive_timer);
 407         schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
 408 }
 409
 410 void nvmet_stop_keep_alive_timer(struct nvmet_ctrl *ctrl)
 411 {
 412         if (unlikely(ctrl->kato == 0))
 413                 return;
 414
 415         pr_debug("ctrl %d stop keep-alive\n", ctrl->cntlid);
 416
 417         cancel_delayed_work_sync(&ctrl->ka_work);
 418 }
 419
 420 struct nvmet_ns *nvmet_find_namespace(struct nvmet_ctrl *ctrl, __le32 nsid)
 421 {
 422         struct nvmet_ns *ns;
 423
 424         ns = xa_load(&ctrl->subsys->namespaces, le32_to_cpu(nsid));
 425         if (ns)
 426                 percpu_ref_get(&ns->ref);
 427
 428         return ns;
 429 }
 430
 431 static void nvmet_destroy_namespace(struct percpu_ref *ref)
 432 {
 433         struct nvmet_ns *ns = container_of(ref, struct nvmet_ns, ref);
 434
 435         complete(&ns->disable_done);
 436 }
 437
 438 void nvmet_put_namespace(struct nvmet_ns *ns)
 439 {
 440         percpu_ref_put(&ns->ref);
 441 }
 442
 443 static void nvmet_ns_dev_disable(struct nvmet_ns *ns)
 444 {
 445         nvmet_bdev_ns_disable(ns);
 446         nvmet_file_ns_disable(ns);
 447 }
 448
 449 static int nvmet_p2pmem_ns_enable(struct nvmet_ns *ns)
 450 {
 451         int ret;
 452         struct pci_dev *p2p_dev;
 453
 454         if (!ns->use_p2pmem)
 455                 return 0;
 456
 457         if (!ns->bdev) {
 458                 pr_err("peer-to-peer DMA is not supported by non-block device namespaces\n");
 459                 return -EINVAL;
 460         }
 461
 462         if (!blk_queue_pci_p2pdma(ns->bdev->bd_disk->queue)) {
 463                 pr_err("peer-to-peer DMA is not supported by the driver of %s\n",
 464                        ns->device_path);
 465                 return -EINVAL;
 466         }
 467
 468         if (ns->p2p_dev) {
 469                 ret = pci_p2pdma_distance(ns->p2p_dev, nvmet_ns_dev(ns), true);
 470                 if (ret < 0)
 471                         return -EINVAL;
 472         } else {
 473                 /*
 474                  * Right now we just check that there is p2pmem available so
 475                  * we can report an error to the user right away if there
 476                  * is not. We'll find the actual device to use once we
 477                  * setup the controller when the port's device is available.
 478                  */
 479
 480                 p2p_dev = pci_p2pmem_find(nvmet_ns_dev(ns));
 481                 if (!p2p_dev) {
 482                         pr_err("no peer-to-peer memory is available for %s\n",
 483                                ns->device_path);
 484                         return -EINVAL;
 485                 }
 486
 487                 pci_dev_put(p2p_dev);
 488         }
 489
 490         return 0;
 491 }
 492
 493 /*
 494  * Note: ctrl->subsys->lock should be held when calling this function
 495  */
 496 static void nvmet_p2pmem_ns_add_p2p(struct nvmet_ctrl *ctrl,
 497                                     struct nvmet_ns *ns)
 498 {
 499         struct device *clients[2];
 500         struct pci_dev *p2p_dev;
 501         int ret;
 502
 503         if (!ctrl->p2p_client || !ns->use_p2pmem)
 504                 return;
 505
 506         if (ns->p2p_dev) {
 507                 ret = pci_p2pdma_distance(ns->p2p_dev, ctrl->p2p_client, true);
 508                 if (ret < 0)
 509                         return;
 510
 511                 p2p_dev = pci_dev_get(ns->p2p_dev);
 512         } else {
 513                 clients[0] = ctrl->p2p_client;
 514                 clients[1] = nvmet_ns_dev(ns);
 515
 516                 p2p_dev = pci_p2pmem_find_many(clients, ARRAY_SIZE(clients));
 517                 if (!p2p_dev) {
 518                         pr_err("no peer-to-peer memory is available that's supported by %s and %s\n",
 519                                dev_name(ctrl->p2p_client), ns->device_path);
 520                         return;
 521                 }
 522         }
 523
 524         ret = radix_tree_insert(&ctrl->p2p_ns_map, ns->nsid, p2p_dev);
 525         if (ret < 0)
 526                 pci_dev_put(p2p_dev);
 527
 528         pr_info("using p2pmem on %s for nsid %d\n", pci_name(p2p_dev),
 529                 ns->nsid);
 530 }
 531
 532 void nvmet_ns_revalidate(struct nvmet_ns *ns)
 533 {
 534         loff_t oldsize = ns->size;
 535
 536         if (ns->bdev)
 537                 nvmet_bdev_ns_revalidate(ns);
 538         else
 539                 nvmet_file_ns_revalidate(ns);
 540
 541         if (oldsize != ns->size)
 542                 nvmet_ns_changed(ns->subsys, ns->nsid);
 543 }
 544
 545 int nvmet_ns_enable(struct nvmet_ns *ns)
 546 {
 547         struct nvmet_subsys *subsys = ns->subsys;
 548         struct nvmet_ctrl *ctrl;
 549         int ret;
 550
 551         mutex_lock(&subsys->lock);
 552         ret = 0;
 553
 554         if (nvmet_passthru_ctrl(subsys)) {
 555                 pr_info("cannot enable both passthru and regular namespaces for a single subsystem");
 556                 goto out_unlock;
 557         }
 558
 559         if (ns->enabled)
 560                 goto out_unlock;
 561
 562         ret = -EMFILE;
 563         if (subsys->nr_namespaces == NVMET_MAX_NAMESPACES)
 564                 goto out_unlock;
 565
 566         ret = nvmet_bdev_ns_enable(ns);
 567         if (ret == -ENOTBLK)
 568                 ret = nvmet_file_ns_enable(ns);
 569         if (ret)
 570                 goto out_unlock;
 571
 572         ret = nvmet_p2pmem_ns_enable(ns);
 573         if (ret)
 574                 goto out_dev_disable;
 575
 576         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 577                 nvmet_p2pmem_ns_add_p2p(ctrl, ns);
 578
 579         ret = percpu_ref_init(&ns->ref, nvmet_destroy_namespace,
 580                                 0, GFP_KERNEL);
 581         if (ret)
 582                 goto out_dev_put;
 583
 584         if (ns->nsid > subsys->max_nsid)
 585                 subsys->max_nsid = ns->nsid;
 586
 587         ret = xa_insert(&subsys->namespaces, ns->nsid, ns, GFP_KERNEL);
 588         if (ret)
 589                 goto out_restore_subsys_maxnsid;
 590
 591         subsys->nr_namespaces++;
 592
 593         nvmet_ns_changed(subsys, ns->nsid);
 594         ns->enabled = true;
 595         ret = 0;
 596 out_unlock:
 597         mutex_unlock(&subsys->lock);
 598         return ret;
 599
 600 out_restore_subsys_maxnsid:
 601         subsys->max_nsid = nvmet_max_nsid(subsys);
 602         percpu_ref_exit(&ns->ref);
 603 out_dev_put:
 604         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 605                 pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
 606 out_dev_disable:
 607         nvmet_ns_dev_disable(ns);
 608         goto out_unlock;
 609 }
 610
 611 void nvmet_ns_disable(struct nvmet_ns *ns)
 612 {
 613         struct nvmet_subsys *subsys = ns->subsys;
 614         struct nvmet_ctrl *ctrl;
 615
 616         mutex_lock(&subsys->lock);
 617         if (!ns->enabled)
 618                 goto out_unlock;
 619
 620         ns->enabled = false;
 621         xa_erase(&ns->subsys->namespaces, ns->nsid);
 622         if (ns->nsid == subsys->max_nsid)
 623                 subsys->max_nsid = nvmet_max_nsid(subsys);
 624
 625         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 626                 pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
 627
 628         mutex_unlock(&subsys->lock);
 629
 630         /*
 631          * Now that we removed the namespaces from the lookup list, we
 632          * can kill the per_cpu ref and wait for any remaining references
 633          * to be dropped, as well as a RCU grace period for anyone only
 634          * using the namepace under rcu_read_lock().  Note that we can't
 635          * use call_rcu here as we need to ensure the namespaces have
 636          * been fully destroyed before unloading the module.
 637          */
 638         percpu_ref_kill(&ns->ref);
 639         synchronize_rcu();
 640         wait_for_completion(&ns->disable_done);
 641         percpu_ref_exit(&ns->ref);
 642
 643         mutex_lock(&subsys->lock);
 644
 645         subsys->nr_namespaces--;
 646         nvmet_ns_changed(subsys, ns->nsid);
 647         nvmet_ns_dev_disable(ns);
 648 out_unlock:
 649         mutex_unlock(&subsys->lock);
 650 }
 651
 652 void nvmet_ns_free(struct nvmet_ns *ns)
 653 {
 654         nvmet_ns_disable(ns);
 655
 656         down_write(&nvmet_ana_sem);
 657         nvmet_ana_group_enabled[ns->anagrpid]--;
 658         up_write(&nvmet_ana_sem);
 659
 660         kfree(ns->device_path);
 661         kfree(ns);
 662 }
 663
 664 struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid)
 665 {
 666         struct nvmet_ns *ns;
 667
 668         ns = kzalloc(sizeof(*ns), GFP_KERNEL);
 669         if (!ns)
 670                 return NULL;
 671
 672         init_completion(&ns->disable_done);
 673
 674         ns->nsid = nsid;
 675         ns->subsys = subsys;
 676
 677         down_write(&nvmet_ana_sem);
 678         ns->anagrpid = NVMET_DEFAULT_ANA_GRPID;
 679         nvmet_ana_group_enabled[ns->anagrpid]++;
 680         up_write(&nvmet_ana_sem);
 681
 682         uuid_gen(&ns->uuid);
 683         ns->buffered_io = false;
 684
 685         return ns;
 686 }
 687
 688 static void nvmet_update_sq_head(struct nvmet_req *req)
 689 {
 690         if (req->sq->size) {
 691                 u32 old_sqhd, new_sqhd;
 692
 693                 do {
 694                         old_sqhd = req->sq->sqhd;
 695                         new_sqhd = (old_sqhd + 1) % req->sq->size;
 696                 } while (cmpxchg(&req->sq->sqhd, old_sqhd, new_sqhd) !=
 697                                         old_sqhd);
 698         }
 699         req->cqe->sq_head = cpu_to_le16(req->sq->sqhd & 0x0000FFFF);
 700 }
 701
 702 static void nvmet_set_error(struct nvmet_req *req, u16 status)
 703 {
 704         struct nvmet_ctrl *ctrl = req->sq->ctrl;
 705         struct nvme_error_slot *new_error_slot;
 706         unsigned long flags;
 707
 708         req->cqe->status = cpu_to_le16(status << 1);
 709
 710         if (!ctrl || req->error_loc == NVMET_NO_ERROR_LOC)
 711                 return;
 712
 713         spin_lock_irqsave(&ctrl->error_lock, flags);
 714         ctrl->err_counter++;
 715         new_error_slot =
 716                 &ctrl->slots[ctrl->err_counter % NVMET_ERROR_LOG_SLOTS];
 717
 718         new_error_slot->error_count = cpu_to_le64(ctrl->err_counter);
 719         new_error_slot->sqid = cpu_to_le16(req->sq->qid);
 720         new_error_slot->cmdid = cpu_to_le16(req->cmd->common.command_id);
 721         new_error_slot->status_field = cpu_to_le16(status << 1);
 722         new_error_slot->param_error_location = cpu_to_le16(req->error_loc);
 723         new_error_slot->lba = cpu_to_le64(req->error_slba);
 724         new_error_slot->nsid = req->cmd->common.nsid;
 725         spin_unlock_irqrestore(&ctrl->error_lock, flags);
 726
 727         /* set the more bit for this request */
 728         req->cqe->status |= cpu_to_le16(1 << 14);
 729 }
 730
 731 static void __nvmet_req_complete(struct nvmet_req *req, u16 status)
 732 {
 733         if (!req->sq->sqhd_disabled)
 734                 nvmet_update_sq_head(req);
 735         req->cqe->sq_id = cpu_to_le16(req->sq->qid);
 736         req->cqe->command_id = req->cmd->common.command_id;
 737
 738         if (unlikely(status))
 739                 nvmet_set_error(req, status);
 740
 741         trace_nvmet_req_complete(req);
 742
 743         if (req->ns)
 744                 nvmet_put_namespace(req->ns);
 745         req->ops->queue_response(req);
 746 }
 747
 748 void nvmet_req_complete(struct nvmet_req *req, u16 status)
 749 {
 750         __nvmet_req_complete(req, status);
 751         percpu_ref_put(&req->sq->ref);
 752 }
 753 EXPORT_SYMBOL_GPL(nvmet_req_complete);
 754
 755 void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq,
 756                 u16 qid, u16 size)
 757 {
 758         cq->qid = qid;
 759         cq->size = size;
 760
 761         ctrl->cqs[qid] = cq;
 762 }
 763
 764 void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq,
 765                 u16 qid, u16 size)
 766 {
 767         sq->sqhd = 0;
 768         sq->qid = qid;
 769         sq->size = size;
 770
 771         ctrl->sqs[qid] = sq;
 772 }
 773
 774 static void nvmet_confirm_sq(struct percpu_ref *ref)
 775 {
 776         struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref);
 777
 778         complete(&sq->confirm_done);
 779 }
 780
 781 void nvmet_sq_destroy(struct nvmet_sq *sq)
 782 {
 783         struct nvmet_ctrl *ctrl = sq->ctrl;
 784
 785         /*
 786          * If this is the admin queue, complete all AERs so that our
 787          * queue doesn't have outstanding requests on it.
 788          */
 789         if (ctrl && ctrl->sqs && ctrl->sqs[0] == sq)
 790                 nvmet_async_events_failall(ctrl);
 791         percpu_ref_kill_and_confirm(&sq->ref, nvmet_confirm_sq);
 792         wait_for_completion(&sq->confirm_done);
 793         wait_for_completion(&sq->free_done);
 794         percpu_ref_exit(&sq->ref);
 795
 796         if (ctrl) {
 797                 nvmet_ctrl_put(ctrl);
 798                 sq->ctrl = NULL; /* allows reusing the queue later */
 799         }
 800 }
 801 EXPORT_SYMBOL_GPL(nvmet_sq_destroy);
 802
 803 static void nvmet_sq_free(struct percpu_ref *ref)
 804 {
 805         struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref);
 806
 807         complete(&sq->free_done);
 808 }
 809
 810 int nvmet_sq_init(struct nvmet_sq *sq)
 811 {
 812         int ret;
 813
 814         ret = percpu_ref_init(&sq->ref, nvmet_sq_free, 0, GFP_KERNEL);
 815         if (ret) {
 816                 pr_err("percpu_ref init failed!\n");
 817                 return ret;
 818         }
 819         init_completion(&sq->free_done);
 820         init_completion(&sq->confirm_done);
 821
 822         return 0;
 823 }
 824 EXPORT_SYMBOL_GPL(nvmet_sq_init);
 825
 826 static inline u16 nvmet_check_ana_state(struct nvmet_port *port,
 827                 struct nvmet_ns *ns)
 828 {
 829         enum nvme_ana_state state = port->ana_state[ns->anagrpid];
 830
 831         if (unlikely(state == NVME_ANA_INACCESSIBLE))
 832                 return NVME_SC_ANA_INACCESSIBLE;
 833         if (unlikely(state == NVME_ANA_PERSISTENT_LOSS))
 834                 return NVME_SC_ANA_PERSISTENT_LOSS;
 835         if (unlikely(state == NVME_ANA_CHANGE))
 836                 return NVME_SC_ANA_TRANSITION;
 837         return 0;
 838 }
 839
 840 static inline u16 nvmet_io_cmd_check_access(struct nvmet_req *req)
 841 {
 842         if (unlikely(req->ns->readonly)) {
 843                 switch (req->cmd->common.opcode) {
 844                 case nvme_cmd_read:
 845                 case nvme_cmd_flush:
 846                         break;
 847                 default:
 848                         return NVME_SC_NS_WRITE_PROTECTED;
 849                 }
 850         }
 851
 852         return 0;
 853 }
 854
 855 static u16 nvmet_parse_io_cmd(struct nvmet_req *req)
 856 {
 857         struct nvme_command *cmd = req->cmd;
 858         u16 ret;
 859
 860         ret = nvmet_check_ctrl_status(req, cmd);
 861         if (unlikely(ret))
 862                 return ret;
 863
 864         if (nvmet_req_passthru_ctrl(req))
 865                 return nvmet_parse_passthru_io_cmd(req);
 866
 867         req->ns = nvmet_find_namespace(req->sq->ctrl, cmd->rw.nsid);
 868         if (unlikely(!req->ns)) {
 869                 req->error_loc = offsetof(struct nvme_common_command, nsid);
 870                 return NVME_SC_INVALID_NS | NVME_SC_DNR;
 871         }
 872         ret = nvmet_check_ana_state(req->port, req->ns);
 873         if (unlikely(ret)) {
 874                 req->error_loc = offsetof(struct nvme_common_command, nsid);
 875                 return ret;
 876         }
 877         ret = nvmet_io_cmd_check_access(req);
 878         if (unlikely(ret)) {
 879                 req->error_loc = offsetof(struct nvme_common_command, nsid);
 880                 return ret;
 881         }
 882
 883         if (req->ns->file)
 884                 return nvmet_file_parse_io_cmd(req);
 885         else
 886                 return nvmet_bdev_parse_io_cmd(req);
 887 }
 888
 889 bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
 890                 struct nvmet_sq *sq, const struct nvmet_fabrics_ops *ops)
 891 {
 892         u8 flags = req->cmd->common.flags;
 893         u16 status;
 894
 895         req->cq = cq;
 896         req->sq = sq;
 897         req->ops = ops;
 898         req->sg = NULL;
 899         req->metadata_sg = NULL;
 900         req->sg_cnt = 0;
 901         req->metadata_sg_cnt = 0;
 902         req->transfer_len = 0;
 903         req->metadata_len = 0;
 904         req->cqe->status = 0;
 905         req->cqe->sq_head = 0;
 906         req->ns = NULL;
 907         req->error_loc = NVMET_NO_ERROR_LOC;
 908         req->error_slba = 0;
 909
 910         trace_nvmet_req_init(req, req->cmd);
 911
 912         /* no support for fused commands yet */
 913         if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) {
 914                 req->error_loc = offsetof(struct nvme_common_command, flags);
 915                 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 916                 goto fail;
 917         }
 918
 919         /*
 920          * For fabrics, PSDT field shall describe metadata pointer (MPTR) that
 921          * contains an address of a single contiguous physical buffer that is
 922          * byte aligned.
 923          */
 924         if (unlikely((flags & NVME_CMD_SGL_ALL) != NVME_CMD_SGL_METABUF)) {
 925                 req->error_loc = offsetof(struct nvme_common_command, flags);
 926                 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 927                 goto fail;
 928         }
 929
 930         if (unlikely(!req->sq->ctrl))
 931                 /* will return an error for any non-connect command: */
 932                 status = nvmet_parse_connect_cmd(req);
 933         else if (likely(req->sq->qid != 0))
 934                 status = nvmet_parse_io_cmd(req);
 935         else
 936                 status = nvmet_parse_admin_cmd(req);
 937
 938         if (status)
 939                 goto fail;
 940
 941         if (unlikely(!percpu_ref_tryget_live(&sq->ref))) {
 942                 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 943                 goto fail;
 944         }
 945
 946         if (sq->ctrl)
 947                 sq->ctrl->cmd_seen = true;
 948
 949         return true;
 950
 951 fail:
 952         __nvmet_req_complete(req, status);
 953         return false;
 954 }
 955 EXPORT_SYMBOL_GPL(nvmet_req_init);
 956
 957 void nvmet_req_uninit(struct nvmet_req *req)
 958 {
 959         percpu_ref_put(&req->sq->ref);
 960         if (req->ns)
 961                 nvmet_put_namespace(req->ns);
 962 }
 963 EXPORT_SYMBOL_GPL(nvmet_req_uninit);
 964
 965 bool nvmet_check_transfer_len(struct nvmet_req *req, size_t len)
 966 {
 967         if (unlikely(len != req->transfer_len)) {
 968                 req->error_loc = offsetof(struct nvme_common_command, dptr);
 969                 nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR);
 970                 return false;
 971         }
 972
 973         return true;
 974 }
 975 EXPORT_SYMBOL_GPL(nvmet_check_transfer_len);
 976
 977 bool nvmet_check_data_len_lte(struct nvmet_req *req, size_t data_len)
 978 {
 979         if (unlikely(data_len > req->transfer_len)) {
 980                 req->error_loc = offsetof(struct nvme_common_command, dptr);
 981                 nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR);
 982                 return false;
 983         }
 984
 985         return true;
 986 }
 987
 988 static unsigned int nvmet_data_transfer_len(struct nvmet_req *req)
 989 {
 990         return req->transfer_len - req->metadata_len;
 991 }
 992
 993 static int nvmet_req_alloc_p2pmem_sgls(struct nvmet_req *req)
 994 {
 995         req->sg = pci_p2pmem_alloc_sgl(req->p2p_dev, &req->sg_cnt,
 996                         nvmet_data_transfer_len(req));
 997         if (!req->sg)
 998                 goto out_err;
 999
1000         if (req->metadata_len) {
1001                 req->metadata_sg = pci_p2pmem_alloc_sgl(req->p2p_dev,
1002                                 &req->metadata_sg_cnt, req->metadata_len);
1003                 if (!req->metadata_sg)
1004                         goto out_free_sg;
1005         }
1006         return 0;
1007 out_free_sg:
1008         pci_p2pmem_free_sgl(req->p2p_dev, req->sg);
1009 out_err:
1010         return -ENOMEM;
1011 }
1012
1013 static bool nvmet_req_find_p2p_dev(struct nvmet_req *req)
1014 {
1015         if (!IS_ENABLED(CONFIG_PCI_P2PDMA))
1016                 return false;
1017
1018         if (req->sq->ctrl && req->sq->qid && req->ns) {
1019                 req->p2p_dev = radix_tree_lookup(&req->sq->ctrl->p2p_ns_map,
1020                                                  req->ns->nsid);
1021                 if (req->p2p_dev)
1022                         return true;
1023         }
1024
1025         req->p2p_dev = NULL;
1026         return false;
1027 }
1028
1029 int nvmet_req_alloc_sgls(struct nvmet_req *req)
1030 {
1031         if (nvmet_req_find_p2p_dev(req) && !nvmet_req_alloc_p2pmem_sgls(req))
1032                 return 0;
1033
1034         req->sg = sgl_alloc(nvmet_data_transfer_len(req), GFP_KERNEL,
1035                             &req->sg_cnt);
1036         if (unlikely(!req->sg))
1037                 goto out;
1038
1039         if (req->metadata_len) {
1040                 req->metadata_sg = sgl_alloc(req->metadata_len, GFP_KERNEL,
1041                                              &req->metadata_sg_cnt);
1042                 if (unlikely(!req->metadata_sg))
1043                         goto out_free;
1044         }
1045
1046         return 0;
1047 out_free:
1048         sgl_free(req->sg);
1049 out:
1050         return -ENOMEM;
1051 }
1052 EXPORT_SYMBOL_GPL(nvmet_req_alloc_sgls);
1053
1054 void nvmet_req_free_sgls(struct nvmet_req *req)
1055 {
1056         if (req->p2p_dev) {
1057                 pci_p2pmem_free_sgl(req->p2p_dev, req->sg);
1058                 if (req->metadata_sg)
1059                         pci_p2pmem_free_sgl(req->p2p_dev, req->metadata_sg);
1060         } else {
1061                 sgl_free(req->sg);
1062                 if (req->metadata_sg)
1063                         sgl_free(req->metadata_sg);
1064         }
1065
1066         req->sg = NULL;
1067         req->metadata_sg = NULL;
1068         req->sg_cnt = 0;
1069         req->metadata_sg_cnt = 0;
1070 }
1071 EXPORT_SYMBOL_GPL(nvmet_req_free_sgls);
1072
1073 static inline bool nvmet_cc_en(u32 cc)
1074 {
1075         return (cc >> NVME_CC_EN_SHIFT) & 0x1;
1076 }
1077
1078 static inline u8 nvmet_cc_css(u32 cc)
1079 {
1080         return (cc >> NVME_CC_CSS_SHIFT) & 0x7;
1081 }
1082
1083 static inline u8 nvmet_cc_mps(u32 cc)
1084 {
1085         return (cc >> NVME_CC_MPS_SHIFT) & 0xf;
1086 }
1087
1088 static inline u8 nvmet_cc_ams(u32 cc)
1089 {
1090         return (cc >> NVME_CC_AMS_SHIFT) & 0x7;
1091 }
1092
1093 static inline u8 nvmet_cc_shn(u32 cc)
1094 {
1095         return (cc >> NVME_CC_SHN_SHIFT) & 0x3;
1096 }
1097
1098 static inline u8 nvmet_cc_iosqes(u32 cc)
1099 {
1100         return (cc >> NVME_CC_IOSQES_SHIFT) & 0xf;
1101 }
1102
1103 static inline u8 nvmet_cc_iocqes(u32 cc)
1104 {
1105         return (cc >> NVME_CC_IOCQES_SHIFT) & 0xf;
1106 }
1107
1108 static void nvmet_start_ctrl(struct nvmet_ctrl *ctrl)
1109 {
1110         lockdep_assert_held(&ctrl->lock);
1111
1112         if (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES ||
1113             nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES ||
1114             nvmet_cc_mps(ctrl->cc) != 0 ||
1115             nvmet_cc_ams(ctrl->cc) != 0 ||
1116             nvmet_cc_css(ctrl->cc) != 0) {
1117                 ctrl->csts = NVME_CSTS_CFS;
1118                 return;
1119         }
1120
1121         ctrl->csts = NVME_CSTS_RDY;
1122
1123         /*
1124          * Controllers that are not yet enabled should not really enforce the
1125          * keep alive timeout, but we still want to track a timeout and cleanup
1126          * in case a host died before it enabled the controller.  Hence, simply
1127          * reset the keep alive timer when the controller is enabled.
1128          */
1129         if (ctrl->kato)
1130                 mod_delayed_work(system_wq, &ctrl->ka_work, ctrl->kato * HZ);
1131 }
1132
1133 static void nvmet_clear_ctrl(struct nvmet_ctrl *ctrl)
1134 {
1135         lockdep_assert_held(&ctrl->lock);
1136
1137         /* XXX: tear down queues? */
1138         ctrl->csts &= ~NVME_CSTS_RDY;
1139         ctrl->cc = 0;
1140 }
1141
1142 void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new)
1143 {
1144         u32 old;
1145
1146         mutex_lock(&ctrl->lock);
1147         old = ctrl->cc;
1148         ctrl->cc = new;
1149
1150         if (nvmet_cc_en(new) && !nvmet_cc_en(old))
1151                 nvmet_start_ctrl(ctrl);
1152         if (!nvmet_cc_en(new) && nvmet_cc_en(old))
1153                 nvmet_clear_ctrl(ctrl);
1154         if (nvmet_cc_shn(new) && !nvmet_cc_shn(old)) {
1155                 nvmet_clear_ctrl(ctrl);
1156                 ctrl->csts |= NVME_CSTS_SHST_CMPLT;
1157         }
1158         if (!nvmet_cc_shn(new) && nvmet_cc_shn(old))
1159                 ctrl->csts &= ~NVME_CSTS_SHST_CMPLT;
1160         mutex_unlock(&ctrl->lock);
1161 }
1162
1163 static void nvmet_init_cap(struct nvmet_ctrl *ctrl)
1164 {
1165         /* command sets supported: NVMe command set: */
1166         ctrl->cap = (1ULL << 37);
1167         /* CC.EN timeout in 500msec units: */
1168         ctrl->cap |= (15ULL << 24);
1169         /* maximum queue entries supported: */
1170         ctrl->cap |= NVMET_QUEUE_SIZE - 1;
1171 }
1172
1173 u16 nvmet_ctrl_find_get(const char *subsysnqn, const char *hostnqn, u16 cntlid,
1174                 struct nvmet_req *req, struct nvmet_ctrl **ret)
1175 {
1176         struct nvmet_subsys *subsys;
1177         struct nvmet_ctrl *ctrl;
1178         u16 status = 0;
1179
1180         subsys = nvmet_find_get_subsys(req->port, subsysnqn);
1181         if (!subsys) {
1182                 pr_warn("connect request for invalid subsystem %s!\n",
1183                         subsysnqn);
1184                 req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn);
1185                 return NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1186         }
1187
1188         mutex_lock(&subsys->lock);
1189         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
1190                 if (ctrl->cntlid == cntlid) {
1191                         if (strncmp(hostnqn, ctrl->hostnqn, NVMF_NQN_SIZE)) {
1192                                 pr_warn("hostnqn mismatch.\n");
1193                                 continue;
1194                         }
1195                         if (!kref_get_unless_zero(&ctrl->ref))
1196                                 continue;
1197
1198                         *ret = ctrl;
1199                         goto out;
1200                 }
1201         }
1202
1203         pr_warn("could not find controller %d for subsys %s / host %s\n",
1204                 cntlid, subsysnqn, hostnqn);
1205         req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(cntlid);
1206         status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1207
1208 out:
1209         mutex_unlock(&subsys->lock);
1210         nvmet_subsys_put(subsys);
1211         return status;
1212 }
1213
1214 u16 nvmet_check_ctrl_status(struct nvmet_req *req, struct nvme_command *cmd)
1215 {
1216         if (unlikely(!(req->sq->ctrl->cc & NVME_CC_ENABLE))) {
1217                 pr_err("got cmd %d while CC.EN == 0 on qid = %d\n",
1218                        cmd->common.opcode, req->sq->qid);
1219                 return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
1220         }
1221
1222         if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
1223                 pr_err("got cmd %d while CSTS.RDY == 0 on qid = %d\n",
1224                        cmd->common.opcode, req->sq->qid);
1225                 return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
1226         }
1227         return 0;
1228 }
1229
1230 bool nvmet_host_allowed(struct nvmet_subsys *subsys, const char *hostnqn)
1231 {
1232         struct nvmet_host_link *p;
1233
1234         lockdep_assert_held(&nvmet_config_sem);
1235
1236         if (subsys->allow_any_host)
1237                 return true;
1238
1239         if (subsys->type == NVME_NQN_DISC) /* allow all access to disc subsys */
1240                 return true;
1241
1242         list_for_each_entry(p, &subsys->hosts, entry) {
1243                 if (!strcmp(nvmet_host_name(p->host), hostnqn))
1244                         return true;
1245         }
1246
1247         return false;
1248 }
1249
1250 /*
1251  * Note: ctrl->subsys->lock should be held when calling this function
1252  */
1253 static void nvmet_setup_p2p_ns_map(struct nvmet_ctrl *ctrl,
1254                 struct nvmet_req *req)
1255 {
1256         struct nvmet_ns *ns;
1257         unsigned long idx;
1258
1259         if (!req->p2p_client)
1260                 return;
1261
1262         ctrl->p2p_client = get_device(req->p2p_client);
1263
1264         xa_for_each(&ctrl->subsys->namespaces, idx, ns)
1265                 nvmet_p2pmem_ns_add_p2p(ctrl, ns);
1266 }
1267
1268 /*
1269  * Note: ctrl->subsys->lock should be held when calling this function
1270  */
1271 static void nvmet_release_p2p_ns_map(struct nvmet_ctrl *ctrl)
1272 {
1273         struct radix_tree_iter iter;
1274         void __rcu **slot;
1275
1276         radix_tree_for_each_slot(slot, &ctrl->p2p_ns_map, &iter, 0)
1277                 pci_dev_put(radix_tree_deref_slot(slot));
1278
1279         put_device(ctrl->p2p_client);
1280 }
1281
1282 static void nvmet_fatal_error_handler(struct work_struct *work)
1283 {
1284         struct nvmet_ctrl *ctrl =
1285                         container_of(work, struct nvmet_ctrl, fatal_err_work);
1286
1287         pr_err("ctrl %d fatal error occurred!\n", ctrl->cntlid);
1288         ctrl->ops->delete_ctrl(ctrl);
1289 }
1290
1291 u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
1292                 struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp)
1293 {
1294         struct nvmet_subsys *subsys;
1295         struct nvmet_ctrl *ctrl;
1296         int ret;
1297         u16 status;
1298
1299         status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1300         subsys = nvmet_find_get_subsys(req->port, subsysnqn);
1301         if (!subsys) {
1302                 pr_warn("connect request for invalid subsystem %s!\n",
1303                         subsysnqn);
1304                 req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn);
1305                 goto out;
1306         }
1307
1308         status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1309         down_read(&nvmet_config_sem);
1310         if (!nvmet_host_allowed(subsys, hostnqn)) {
1311                 pr_info("connect by host %s for subsystem %s not allowed\n",
1312                         hostnqn, subsysnqn);
1313                 req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(hostnqn);
1314                 up_read(&nvmet_config_sem);
1315                 status = NVME_SC_CONNECT_INVALID_HOST | NVME_SC_DNR;
1316                 goto out_put_subsystem;
1317         }
1318         up_read(&nvmet_config_sem);
1319
1320         status = NVME_SC_INTERNAL;
1321         ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
1322         if (!ctrl)
1323                 goto out_put_subsystem;
1324         mutex_init(&ctrl->lock);
1325
1326         nvmet_init_cap(ctrl);
1327
1328         ctrl->port = req->port;
1329
1330         INIT_WORK(&ctrl->async_event_work, nvmet_async_event_work);
1331         INIT_LIST_HEAD(&ctrl->async_events);
1332         INIT_RADIX_TREE(&ctrl->p2p_ns_map, GFP_KERNEL);
1333         INIT_WORK(&ctrl->fatal_err_work, nvmet_fatal_error_handler);
1334
1335         memcpy(ctrl->subsysnqn, subsysnqn, NVMF_NQN_SIZE);
1336         memcpy(ctrl->hostnqn, hostnqn, NVMF_NQN_SIZE);
1337
1338         kref_init(&ctrl->ref);
1339         ctrl->subsys = subsys;
1340         WRITE_ONCE(ctrl->aen_enabled, NVMET_AEN_CFG_OPTIONAL);
1341
1342         ctrl->changed_ns_list = kmalloc_array(NVME_MAX_CHANGED_NAMESPACES,
1343                         sizeof(__le32), GFP_KERNEL);
1344         if (!ctrl->changed_ns_list)
1345                 goto out_free_ctrl;
1346
1347         ctrl->cqs = kcalloc(subsys->max_qid + 1,
1348                         sizeof(struct nvmet_cq *),
1349                         GFP_KERNEL);
1350         if (!ctrl->cqs)
1351                 goto out_free_changed_ns_list;
1352
1353         ctrl->sqs = kcalloc(subsys->max_qid + 1,
1354                         sizeof(struct nvmet_sq *),
1355                         GFP_KERNEL);
1356         if (!ctrl->sqs)
1357                 goto out_free_cqs;
1358
1359         if (subsys->cntlid_min > subsys->cntlid_max)
1360                 goto out_free_cqs;
1361
1362         ret = ida_simple_get(&cntlid_ida,
1363                              subsys->cntlid_min, subsys->cntlid_max,
1364                              GFP_KERNEL);
1365         if (ret < 0) {
1366                 status = NVME_SC_CONNECT_CTRL_BUSY | NVME_SC_DNR;
1367                 goto out_free_sqs;
1368         }
1369         ctrl->cntlid = ret;
1370
1371         ctrl->ops = req->ops;
1372
1373         /*
1374          * Discovery controllers may use some arbitrary high value
1375          * in order to cleanup stale discovery sessions
1376          */
1377         if ((ctrl->subsys->type == NVME_NQN_DISC) && !kato)
1378                 kato = NVMET_DISC_KATO_MS;
1379
1380         /* keep-alive timeout in seconds */
1381         ctrl->kato = DIV_ROUND_UP(kato, 1000);
1382
1383         ctrl->err_counter = 0;
1384         spin_lock_init(&ctrl->error_lock);
1385
1386         nvmet_start_keep_alive_timer(ctrl);
1387
1388         mutex_lock(&subsys->lock);
1389         list_add_tail(&ctrl->subsys_entry, &subsys->ctrls);
1390         nvmet_setup_p2p_ns_map(ctrl, req);
1391         mutex_unlock(&subsys->lock);
1392
1393         *ctrlp = ctrl;
1394         return 0;
1395
1396 out_free_sqs:
1397         kfree(ctrl->sqs);
1398 out_free_cqs:
1399         kfree(ctrl->cqs);
1400 out_free_changed_ns_list:
1401         kfree(ctrl->changed_ns_list);
1402 out_free_ctrl:
1403         kfree(ctrl);
1404 out_put_subsystem:
1405         nvmet_subsys_put(subsys);
1406 out:
1407         return status;
1408 }
1409
1410 static void nvmet_ctrl_free(struct kref *ref)
1411 {
1412         struct nvmet_ctrl *ctrl = container_of(ref, struct nvmet_ctrl, ref);
1413         struct nvmet_subsys *subsys = ctrl->subsys;
1414
1415         mutex_lock(&subsys->lock);
1416         nvmet_release_p2p_ns_map(ctrl);
1417         list_del(&ctrl->subsys_entry);
1418         mutex_unlock(&subsys->lock);
1419
1420         nvmet_stop_keep_alive_timer(ctrl);
1421
1422         flush_work(&ctrl->async_event_work);
1423         cancel_work_sync(&ctrl->fatal_err_work);
1424
1425         ida_simple_remove(&cntlid_ida, ctrl->cntlid);
1426
1427         nvmet_async_events_free(ctrl);
1428         kfree(ctrl->sqs);
1429         kfree(ctrl->cqs);
1430         kfree(ctrl->changed_ns_list);
1431         kfree(ctrl);
1432
1433         nvmet_subsys_put(subsys);
1434 }
1435
1436 void nvmet_ctrl_put(struct nvmet_ctrl *ctrl)
1437 {
1438         kref_put(&ctrl->ref, nvmet_ctrl_free);
1439 }
1440
1441 void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl)
1442 {
1443         mutex_lock(&ctrl->lock);
1444         if (!(ctrl->csts & NVME_CSTS_CFS)) {
1445                 ctrl->csts |= NVME_CSTS_CFS;
1446                 schedule_work(&ctrl->fatal_err_work);
1447         }
1448         mutex_unlock(&ctrl->lock);
1449 }
1450 EXPORT_SYMBOL_GPL(nvmet_ctrl_fatal_error);
1451
1452 static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
1453                 const char *subsysnqn)
1454 {
1455         struct nvmet_subsys_link *p;
1456
1457         if (!port)
1458                 return NULL;
1459
1460         if (!strcmp(NVME_DISC_SUBSYS_NAME, subsysnqn)) {
1461                 if (!kref_get_unless_zero(&nvmet_disc_subsys->ref))
1462                         return NULL;
1463                 return nvmet_disc_subsys;
1464         }
1465
1466         down_read(&nvmet_config_sem);
1467         list_for_each_entry(p, &port->subsystems, entry) {
1468                 if (!strncmp(p->subsys->subsysnqn, subsysnqn,
1469                                 NVMF_NQN_SIZE)) {
1470                         if (!kref_get_unless_zero(&p->subsys->ref))
1471                                 break;
1472                         up_read(&nvmet_config_sem);
1473                         return p->subsys;
1474                 }
1475         }
1476         up_read(&nvmet_config_sem);
1477         return NULL;
1478 }
1479
1480 struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
1481                 enum nvme_subsys_type type)
1482 {
1483         struct nvmet_subsys *subsys;
1484
1485         subsys = kzalloc(sizeof(*subsys), GFP_KERNEL);
1486         if (!subsys)
1487                 return ERR_PTR(-ENOMEM);
1488
1489         subsys->ver = NVMET_DEFAULT_VS;
1490         /* generate a random serial number as our controllers are ephemeral: */
1491         get_random_bytes(&subsys->serial, sizeof(subsys->serial));
1492
1493         switch (type) {
1494         case NVME_NQN_NVME:
1495                 subsys->max_qid = NVMET_NR_QUEUES;
1496                 break;
1497         case NVME_NQN_DISC:
1498                 subsys->max_qid = 0;
1499                 break;
1500         default:
1501                 pr_err("%s: Unknown Subsystem type - %d\n", __func__, type);
1502                 kfree(subsys);
1503                 return ERR_PTR(-EINVAL);
1504         }
1505         subsys->type = type;
1506         subsys->subsysnqn = kstrndup(subsysnqn, NVMF_NQN_SIZE,
1507                         GFP_KERNEL);
1508         if (!subsys->subsysnqn) {
1509                 kfree(subsys);
1510                 return ERR_PTR(-ENOMEM);
1511         }
1512         subsys->cntlid_min = NVME_CNTLID_MIN;
1513         subsys->cntlid_max = NVME_CNTLID_MAX;
1514         kref_init(&subsys->ref);
1515
1516         mutex_init(&subsys->lock);
1517         xa_init(&subsys->namespaces);
1518         INIT_LIST_HEAD(&subsys->ctrls);
1519         INIT_LIST_HEAD(&subsys->hosts);
1520
1521         return subsys;
1522 }
1523
1524 static void nvmet_subsys_free(struct kref *ref)
1525 {
1526         struct nvmet_subsys *subsys =
1527                 container_of(ref, struct nvmet_subsys, ref);
1528
1529         WARN_ON_ONCE(!xa_empty(&subsys->namespaces));
1530
1531         xa_destroy(&subsys->namespaces);
1532         nvmet_passthru_subsys_free(subsys);
1533
1534         kfree(subsys->subsysnqn);
1535         kfree_rcu(subsys->model, rcuhead);
1536         kfree(subsys);
1537 }
1538
1539 void nvmet_subsys_del_ctrls(struct nvmet_subsys *subsys)
1540 {
1541         struct nvmet_ctrl *ctrl;
1542
1543         mutex_lock(&subsys->lock);
1544         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
1545                 ctrl->ops->delete_ctrl(ctrl);
1546         mutex_unlock(&subsys->lock);
1547 }
1548
1549 void nvmet_subsys_put(struct nvmet_subsys *subsys)
1550 {
1551         kref_put(&subsys->ref, nvmet_subsys_free);
1552 }
1553
1554 static int __init nvmet_init(void)
1555 {
1556         int error;
1557
1558         nvmet_ana_group_enabled[NVMET_DEFAULT_ANA_GRPID] = 1;
1559
1560         buffered_io_wq = alloc_workqueue("nvmet-buffered-io-wq",
1561                         WQ_MEM_RECLAIM, 0);
1562         if (!buffered_io_wq) {
1563                 error = -ENOMEM;
1564                 goto out;
1565         }
1566
1567         error = nvmet_init_discovery();
1568         if (error)
1569                 goto out_free_work_queue;
1570
1571         error = nvmet_init_configfs();
1572         if (error)
1573                 goto out_exit_discovery;
1574         return 0;
1575
1576 out_exit_discovery:
1577         nvmet_exit_discovery();
1578 out_free_work_queue:
1579         destroy_workqueue(buffered_io_wq);
1580 out:
1581         return error;
1582 }
1583
1584 static void __exit nvmet_exit(void)
1585 {
1586         nvmet_exit_configfs();
1587         nvmet_exit_discovery();
1588         ida_destroy(&cntlid_ida);
1589         destroy_workqueue(buffered_io_wq);
1590
1591         BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_entry) != 1024);
1592         BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_hdr) != 1024);
1593 }
1594
1595 module_init(nvmet_init);
1596 module_exit(nvmet_exit);
1597
1598 MODULE_LICENSE("GPL v2");