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 #include <generated/utsrelease.h>
  14
  15 #define CREATE_TRACE_POINTS
  16 #include "trace.h"
  17
  18 #include "nvmet.h"
  19
  20 struct kmem_cache *nvmet_bvec_cache;
  21 struct workqueue_struct *buffered_io_wq;
  22 struct workqueue_struct *zbd_wq;
  23 static const struct nvmet_fabrics_ops *nvmet_transports[NVMF_TRTYPE_MAX];
  24 static DEFINE_IDA(cntlid_ida);
  25
  26 struct workqueue_struct *nvmet_wq;
  27 EXPORT_SYMBOL_GPL(nvmet_wq);
  28
  29 /*
  30  * This read/write semaphore is used to synchronize access to configuration
  31  * information on a target system that will result in discovery log page
  32  * information change for at least one host.
  33  * The full list of resources to protected by this semaphore is:
  34  *
  35  *  - subsystems list
  36  *  - per-subsystem allowed hosts list
  37  *  - allow_any_host subsystem attribute
  38  *  - nvmet_genctr
  39  *  - the nvmet_transports array
  40  *
  41  * When updating any of those lists/structures write lock should be obtained,
  42  * while when reading (popolating discovery log page or checking host-subsystem
  43  * link) read lock is obtained to allow concurrent reads.
  44  */
  45 DECLARE_RWSEM(nvmet_config_sem);
  46
  47 u32 nvmet_ana_group_enabled[NVMET_MAX_ANAGRPS + 1];
  48 u64 nvmet_ana_chgcnt;
  49 DECLARE_RWSEM(nvmet_ana_sem);
  50
  51 inline u16 errno_to_nvme_status(struct nvmet_req *req, int errno)
  52 {
  53         switch (errno) {
  54         case 0:
  55                 return NVME_SC_SUCCESS;
  56         case -ENOSPC:
  57                 req->error_loc = offsetof(struct nvme_rw_command, length);
  58                 return NVME_SC_CAP_EXCEEDED | NVME_SC_DNR;
  59         case -EREMOTEIO:
  60                 req->error_loc = offsetof(struct nvme_rw_command, slba);
  61                 return  NVME_SC_LBA_RANGE | NVME_SC_DNR;
  62         case -EOPNOTSUPP:
  63                 req->error_loc = offsetof(struct nvme_common_command, opcode);
  64                 switch (req->cmd->common.opcode) {
  65                 case nvme_cmd_dsm:
  66                 case nvme_cmd_write_zeroes:
  67                         return NVME_SC_ONCS_NOT_SUPPORTED | NVME_SC_DNR;
  68                 default:
  69                         return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
  70                 }
  71                 break;
  72         case -ENODATA:
  73                 req->error_loc = offsetof(struct nvme_rw_command, nsid);
  74                 return NVME_SC_ACCESS_DENIED;
  75         case -EIO:
  76                 fallthrough;
  77         default:
  78                 req->error_loc = offsetof(struct nvme_common_command, opcode);
  79                 return NVME_SC_INTERNAL | NVME_SC_DNR;
  80         }
  81 }
  82
  83 u16 nvmet_report_invalid_opcode(struct nvmet_req *req)
  84 {
  85         pr_debug("unhandled cmd %d on qid %d\n", req->cmd->common.opcode,
  86                  req->sq->qid);
  87
  88         req->error_loc = offsetof(struct nvme_common_command, opcode);
  89         return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
  90 }
  91
  92 static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
  93                 const char *subsysnqn);
  94
  95 u16 nvmet_copy_to_sgl(struct nvmet_req *req, off_t off, const void *buf,
  96                 size_t len)
  97 {
  98         if (sg_pcopy_from_buffer(req->sg, req->sg_cnt, buf, len, off) != len) {
  99                 req->error_loc = offsetof(struct nvme_common_command, dptr);
 100                 return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
 101         }
 102         return 0;
 103 }
 104
 105 u16 nvmet_copy_from_sgl(struct nvmet_req *req, off_t off, void *buf, size_t len)
 106 {
 107         if (sg_pcopy_to_buffer(req->sg, req->sg_cnt, buf, len, off) != len) {
 108                 req->error_loc = offsetof(struct nvme_common_command, dptr);
 109                 return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
 110         }
 111         return 0;
 112 }
 113
 114 u16 nvmet_zero_sgl(struct nvmet_req *req, off_t off, size_t len)
 115 {
 116         if (sg_zero_buffer(req->sg, req->sg_cnt, len, off) != len) {
 117                 req->error_loc = offsetof(struct nvme_common_command, dptr);
 118                 return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
 119         }
 120         return 0;
 121 }
 122
 123 static u32 nvmet_max_nsid(struct nvmet_subsys *subsys)
 124 {
 125         struct nvmet_ns *cur;
 126         unsigned long idx;
 127         u32 nsid = 0;
 128
 129         xa_for_each(&subsys->namespaces, idx, cur)
 130                 nsid = cur->nsid;
 131
 132         return nsid;
 133 }
 134
 135 static u32 nvmet_async_event_result(struct nvmet_async_event *aen)
 136 {
 137         return aen->event_type | (aen->event_info << 8) | (aen->log_page << 16);
 138 }
 139
 140 static void nvmet_async_events_failall(struct nvmet_ctrl *ctrl)
 141 {
 142         struct nvmet_req *req;
 143
 144         mutex_lock(&ctrl->lock);
 145         while (ctrl->nr_async_event_cmds) {
 146                 req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds];
 147                 mutex_unlock(&ctrl->lock);
 148                 nvmet_req_complete(req, NVME_SC_INTERNAL | NVME_SC_DNR);
 149                 mutex_lock(&ctrl->lock);
 150         }
 151         mutex_unlock(&ctrl->lock);
 152 }
 153
 154 static void nvmet_async_events_process(struct nvmet_ctrl *ctrl)
 155 {
 156         struct nvmet_async_event *aen;
 157         struct nvmet_req *req;
 158
 159         mutex_lock(&ctrl->lock);
 160         while (ctrl->nr_async_event_cmds && !list_empty(&ctrl->async_events)) {
 161                 aen = list_first_entry(&ctrl->async_events,
 162                                        struct nvmet_async_event, entry);
 163                 req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds];
 164                 nvmet_set_result(req, nvmet_async_event_result(aen));
 165
 166                 list_del(&aen->entry);
 167                 kfree(aen);
 168
 169                 mutex_unlock(&ctrl->lock);
 170                 trace_nvmet_async_event(ctrl, req->cqe->result.u32);
 171                 nvmet_req_complete(req, 0);
 172                 mutex_lock(&ctrl->lock);
 173         }
 174         mutex_unlock(&ctrl->lock);
 175 }
 176
 177 static void nvmet_async_events_free(struct nvmet_ctrl *ctrl)
 178 {
 179         struct nvmet_async_event *aen, *tmp;
 180
 181         mutex_lock(&ctrl->lock);
 182         list_for_each_entry_safe(aen, tmp, &ctrl->async_events, entry) {
 183                 list_del(&aen->entry);
 184                 kfree(aen);
 185         }
 186         mutex_unlock(&ctrl->lock);
 187 }
 188
 189 static void nvmet_async_event_work(struct work_struct *work)
 190 {
 191         struct nvmet_ctrl *ctrl =
 192                 container_of(work, struct nvmet_ctrl, async_event_work);
 193
 194         nvmet_async_events_process(ctrl);
 195 }
 196
 197 void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type,
 198                 u8 event_info, u8 log_page)
 199 {
 200         struct nvmet_async_event *aen;
 201
 202         aen = kmalloc(sizeof(*aen), GFP_KERNEL);
 203         if (!aen)
 204                 return;
 205
 206         aen->event_type = event_type;
 207         aen->event_info = event_info;
 208         aen->log_page = log_page;
 209
 210         mutex_lock(&ctrl->lock);
 211         list_add_tail(&aen->entry, &ctrl->async_events);
 212         mutex_unlock(&ctrl->lock);
 213
 214         queue_work(nvmet_wq, &ctrl->async_event_work);
 215 }
 216
 217 static void nvmet_add_to_changed_ns_log(struct nvmet_ctrl *ctrl, __le32 nsid)
 218 {
 219         u32 i;
 220
 221         mutex_lock(&ctrl->lock);
 222         if (ctrl->nr_changed_ns > NVME_MAX_CHANGED_NAMESPACES)
 223                 goto out_unlock;
 224
 225         for (i = 0; i < ctrl->nr_changed_ns; i++) {
 226                 if (ctrl->changed_ns_list[i] == nsid)
 227                         goto out_unlock;
 228         }
 229
 230         if (ctrl->nr_changed_ns == NVME_MAX_CHANGED_NAMESPACES) {
 231                 ctrl->changed_ns_list[0] = cpu_to_le32(0xffffffff);
 232                 ctrl->nr_changed_ns = U32_MAX;
 233                 goto out_unlock;
 234         }
 235
 236         ctrl->changed_ns_list[ctrl->nr_changed_ns++] = nsid;
 237 out_unlock:
 238         mutex_unlock(&ctrl->lock);
 239 }
 240
 241 void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid)
 242 {
 243         struct nvmet_ctrl *ctrl;
 244
 245         lockdep_assert_held(&subsys->lock);
 246
 247         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
 248                 nvmet_add_to_changed_ns_log(ctrl, cpu_to_le32(nsid));
 249                 if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_NS_ATTR))
 250                         continue;
 251                 nvmet_add_async_event(ctrl, NVME_AER_NOTICE,
 252                                 NVME_AER_NOTICE_NS_CHANGED,
 253                                 NVME_LOG_CHANGED_NS);
 254         }
 255 }
 256
 257 void nvmet_send_ana_event(struct nvmet_subsys *subsys,
 258                 struct nvmet_port *port)
 259 {
 260         struct nvmet_ctrl *ctrl;
 261
 262         mutex_lock(&subsys->lock);
 263         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
 264                 if (port && ctrl->port != port)
 265                         continue;
 266                 if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_ANA_CHANGE))
 267                         continue;
 268                 nvmet_add_async_event(ctrl, NVME_AER_NOTICE,
 269                                 NVME_AER_NOTICE_ANA, NVME_LOG_ANA);
 270         }
 271         mutex_unlock(&subsys->lock);
 272 }
 273
 274 void nvmet_port_send_ana_event(struct nvmet_port *port)
 275 {
 276         struct nvmet_subsys_link *p;
 277
 278         down_read(&nvmet_config_sem);
 279         list_for_each_entry(p, &port->subsystems, entry)
 280                 nvmet_send_ana_event(p->subsys, port);
 281         up_read(&nvmet_config_sem);
 282 }
 283
 284 int nvmet_register_transport(const struct nvmet_fabrics_ops *ops)
 285 {
 286         int ret = 0;
 287
 288         down_write(&nvmet_config_sem);
 289         if (nvmet_transports[ops->type])
 290                 ret = -EINVAL;
 291         else
 292                 nvmet_transports[ops->type] = ops;
 293         up_write(&nvmet_config_sem);
 294
 295         return ret;
 296 }
 297 EXPORT_SYMBOL_GPL(nvmet_register_transport);
 298
 299 void nvmet_unregister_transport(const struct nvmet_fabrics_ops *ops)
 300 {
 301         down_write(&nvmet_config_sem);
 302         nvmet_transports[ops->type] = NULL;
 303         up_write(&nvmet_config_sem);
 304 }
 305 EXPORT_SYMBOL_GPL(nvmet_unregister_transport);
 306
 307 void nvmet_port_del_ctrls(struct nvmet_port *port, struct nvmet_subsys *subsys)
 308 {
 309         struct nvmet_ctrl *ctrl;
 310
 311         mutex_lock(&subsys->lock);
 312         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
 313                 if (ctrl->port == port)
 314                         ctrl->ops->delete_ctrl(ctrl);
 315         }
 316         mutex_unlock(&subsys->lock);
 317 }
 318
 319 int nvmet_enable_port(struct nvmet_port *port)
 320 {
 321         const struct nvmet_fabrics_ops *ops;
 322         int ret;
 323
 324         lockdep_assert_held(&nvmet_config_sem);
 325
 326         ops = nvmet_transports[port->disc_addr.trtype];
 327         if (!ops) {
 328                 up_write(&nvmet_config_sem);
 329                 request_module("nvmet-transport-%d", port->disc_addr.trtype);
 330                 down_write(&nvmet_config_sem);
 331                 ops = nvmet_transports[port->disc_addr.trtype];
 332                 if (!ops) {
 333                         pr_err("transport type %d not supported\n",
 334                                 port->disc_addr.trtype);
 335                         return -EINVAL;
 336                 }
 337         }
 338
 339         if (!try_module_get(ops->owner))
 340                 return -EINVAL;
 341
 342         /*
 343          * If the user requested PI support and the transport isn't pi capable,
 344          * don't enable the port.
 345          */
 346         if (port->pi_enable && !(ops->flags & NVMF_METADATA_SUPPORTED)) {
 347                 pr_err("T10-PI is not supported by transport type %d\n",
 348                        port->disc_addr.trtype);
 349                 ret = -EINVAL;
 350                 goto out_put;
 351         }
 352
 353         ret = ops->add_port(port);
 354         if (ret)
 355                 goto out_put;
 356
 357         /* If the transport didn't set inline_data_size, then disable it. */
 358         if (port->inline_data_size < 0)
 359                 port->inline_data_size = 0;
 360
 361         /*
 362          * If the transport didn't set the max_queue_size properly, then clamp
 363          * it to the target limits. Also set default values in case the
 364          * transport didn't set it at all.
 365          */
 366         if (port->max_queue_size < 0)
 367                 port->max_queue_size = NVMET_MAX_QUEUE_SIZE;
 368         else
 369                 port->max_queue_size = clamp_t(int, port->max_queue_size,
 370                                                NVMET_MIN_QUEUE_SIZE,
 371                                                NVMET_MAX_QUEUE_SIZE);
 372
 373         port->enabled = true;
 374         port->tr_ops = ops;
 375         return 0;
 376
 377 out_put:
 378         module_put(ops->owner);
 379         return ret;
 380 }
 381
 382 void nvmet_disable_port(struct nvmet_port *port)
 383 {
 384         const struct nvmet_fabrics_ops *ops;
 385
 386         lockdep_assert_held(&nvmet_config_sem);
 387
 388         port->enabled = false;
 389         port->tr_ops = NULL;
 390
 391         ops = nvmet_transports[port->disc_addr.trtype];
 392         ops->remove_port(port);
 393         module_put(ops->owner);
 394 }
 395
 396 static void nvmet_keep_alive_timer(struct work_struct *work)
 397 {
 398         struct nvmet_ctrl *ctrl = container_of(to_delayed_work(work),
 399                         struct nvmet_ctrl, ka_work);
 400         bool reset_tbkas = ctrl->reset_tbkas;
 401
 402         ctrl->reset_tbkas = false;
 403         if (reset_tbkas) {
 404                 pr_debug("ctrl %d reschedule traffic based keep-alive timer\n",
 405                         ctrl->cntlid);
 406                 queue_delayed_work(nvmet_wq, &ctrl->ka_work, ctrl->kato * HZ);
 407                 return;
 408         }
 409
 410         pr_err("ctrl %d keep-alive timer (%d seconds) expired!\n",
 411                 ctrl->cntlid, ctrl->kato);
 412
 413         nvmet_ctrl_fatal_error(ctrl);
 414 }
 415
 416 void nvmet_start_keep_alive_timer(struct nvmet_ctrl *ctrl)
 417 {
 418         if (unlikely(ctrl->kato == 0))
 419                 return;
 420
 421         pr_debug("ctrl %d start keep-alive timer for %d secs\n",
 422                 ctrl->cntlid, ctrl->kato);
 423
 424         queue_delayed_work(nvmet_wq, &ctrl->ka_work, ctrl->kato * HZ);
 425 }
 426
 427 void nvmet_stop_keep_alive_timer(struct nvmet_ctrl *ctrl)
 428 {
 429         if (unlikely(ctrl->kato == 0))
 430                 return;
 431
 432         pr_debug("ctrl %d stop keep-alive\n", ctrl->cntlid);
 433
 434         cancel_delayed_work_sync(&ctrl->ka_work);
 435 }
 436
 437 u16 nvmet_req_find_ns(struct nvmet_req *req)
 438 {
 439         u32 nsid = le32_to_cpu(req->cmd->common.nsid);
 440
 441         req->ns = xa_load(&nvmet_req_subsys(req)->namespaces, nsid);
 442         if (unlikely(!req->ns)) {
 443                 req->error_loc = offsetof(struct nvme_common_command, nsid);
 444                 return NVME_SC_INVALID_NS | NVME_SC_DNR;
 445         }
 446
 447         percpu_ref_get(&req->ns->ref);
 448         return NVME_SC_SUCCESS;
 449 }
 450
 451 static void nvmet_destroy_namespace(struct percpu_ref *ref)
 452 {
 453         struct nvmet_ns *ns = container_of(ref, struct nvmet_ns, ref);
 454
 455         complete(&ns->disable_done);
 456 }
 457
 458 void nvmet_put_namespace(struct nvmet_ns *ns)
 459 {
 460         percpu_ref_put(&ns->ref);
 461 }
 462
 463 static void nvmet_ns_dev_disable(struct nvmet_ns *ns)
 464 {
 465         nvmet_bdev_ns_disable(ns);
 466         nvmet_file_ns_disable(ns);
 467 }
 468
 469 static int nvmet_p2pmem_ns_enable(struct nvmet_ns *ns)
 470 {
 471         int ret;
 472         struct pci_dev *p2p_dev;
 473
 474         if (!ns->use_p2pmem)
 475                 return 0;
 476
 477         if (!ns->bdev) {
 478                 pr_err("peer-to-peer DMA is not supported by non-block device namespaces\n");
 479                 return -EINVAL;
 480         }
 481
 482         if (!blk_queue_pci_p2pdma(ns->bdev->bd_disk->queue)) {
 483                 pr_err("peer-to-peer DMA is not supported by the driver of %s\n",
 484                        ns->device_path);
 485                 return -EINVAL;
 486         }
 487
 488         if (ns->p2p_dev) {
 489                 ret = pci_p2pdma_distance(ns->p2p_dev, nvmet_ns_dev(ns), true);
 490                 if (ret < 0)
 491                         return -EINVAL;
 492         } else {
 493                 /*
 494                  * Right now we just check that there is p2pmem available so
 495                  * we can report an error to the user right away if there
 496                  * is not. We'll find the actual device to use once we
 497                  * setup the controller when the port's device is available.
 498                  */
 499
 500                 p2p_dev = pci_p2pmem_find(nvmet_ns_dev(ns));
 501                 if (!p2p_dev) {
 502                         pr_err("no peer-to-peer memory is available for %s\n",
 503                                ns->device_path);
 504                         return -EINVAL;
 505                 }
 506
 507                 pci_dev_put(p2p_dev);
 508         }
 509
 510         return 0;
 511 }
 512
 513 /*
 514  * Note: ctrl->subsys->lock should be held when calling this function
 515  */
 516 static void nvmet_p2pmem_ns_add_p2p(struct nvmet_ctrl *ctrl,
 517                                     struct nvmet_ns *ns)
 518 {
 519         struct device *clients[2];
 520         struct pci_dev *p2p_dev;
 521         int ret;
 522
 523         if (!ctrl->p2p_client || !ns->use_p2pmem)
 524                 return;
 525
 526         if (ns->p2p_dev) {
 527                 ret = pci_p2pdma_distance(ns->p2p_dev, ctrl->p2p_client, true);
 528                 if (ret < 0)
 529                         return;
 530
 531                 p2p_dev = pci_dev_get(ns->p2p_dev);
 532         } else {
 533                 clients[0] = ctrl->p2p_client;
 534                 clients[1] = nvmet_ns_dev(ns);
 535
 536                 p2p_dev = pci_p2pmem_find_many(clients, ARRAY_SIZE(clients));
 537                 if (!p2p_dev) {
 538                         pr_err("no peer-to-peer memory is available that's supported by %s and %s\n",
 539                                dev_name(ctrl->p2p_client), ns->device_path);
 540                         return;
 541                 }
 542         }
 543
 544         ret = radix_tree_insert(&ctrl->p2p_ns_map, ns->nsid, p2p_dev);
 545         if (ret < 0)
 546                 pci_dev_put(p2p_dev);
 547
 548         pr_info("using p2pmem on %s for nsid %d\n", pci_name(p2p_dev),
 549                 ns->nsid);
 550 }
 551
 552 bool nvmet_ns_revalidate(struct nvmet_ns *ns)
 553 {
 554         loff_t oldsize = ns->size;
 555
 556         if (ns->bdev)
 557                 nvmet_bdev_ns_revalidate(ns);
 558         else
 559                 nvmet_file_ns_revalidate(ns);
 560
 561         return oldsize != ns->size;
 562 }
 563
 564 int nvmet_ns_enable(struct nvmet_ns *ns)
 565 {
 566         struct nvmet_subsys *subsys = ns->subsys;
 567         struct nvmet_ctrl *ctrl;
 568         int ret;
 569
 570         mutex_lock(&subsys->lock);
 571         ret = 0;
 572
 573         if (nvmet_is_passthru_subsys(subsys)) {
 574                 pr_info("cannot enable both passthru and regular namespaces for a single subsystem");
 575                 goto out_unlock;
 576         }
 577
 578         if (ns->enabled)
 579                 goto out_unlock;
 580
 581         ret = -EMFILE;
 582         if (subsys->nr_namespaces == NVMET_MAX_NAMESPACES)
 583                 goto out_unlock;
 584
 585         ret = nvmet_bdev_ns_enable(ns);
 586         if (ret == -ENOTBLK)
 587                 ret = nvmet_file_ns_enable(ns);
 588         if (ret)
 589                 goto out_unlock;
 590
 591         ret = nvmet_p2pmem_ns_enable(ns);
 592         if (ret)
 593                 goto out_dev_disable;
 594
 595         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 596                 nvmet_p2pmem_ns_add_p2p(ctrl, ns);
 597
 598         ret = percpu_ref_init(&ns->ref, nvmet_destroy_namespace,
 599                                 0, GFP_KERNEL);
 600         if (ret)
 601                 goto out_dev_put;
 602
 603         if (ns->nsid > subsys->max_nsid)
 604                 subsys->max_nsid = ns->nsid;
 605
 606         ret = xa_insert(&subsys->namespaces, ns->nsid, ns, GFP_KERNEL);
 607         if (ret)
 608                 goto out_restore_subsys_maxnsid;
 609
 610         subsys->nr_namespaces++;
 611
 612         nvmet_ns_changed(subsys, ns->nsid);
 613         ns->enabled = true;
 614         ret = 0;
 615 out_unlock:
 616         mutex_unlock(&subsys->lock);
 617         return ret;
 618
 619 out_restore_subsys_maxnsid:
 620         subsys->max_nsid = nvmet_max_nsid(subsys);
 621         percpu_ref_exit(&ns->ref);
 622 out_dev_put:
 623         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 624                 pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
 625 out_dev_disable:
 626         nvmet_ns_dev_disable(ns);
 627         goto out_unlock;
 628 }
 629
 630 void nvmet_ns_disable(struct nvmet_ns *ns)
 631 {
 632         struct nvmet_subsys *subsys = ns->subsys;
 633         struct nvmet_ctrl *ctrl;
 634
 635         mutex_lock(&subsys->lock);
 636         if (!ns->enabled)
 637                 goto out_unlock;
 638
 639         ns->enabled = false;
 640         xa_erase(&ns->subsys->namespaces, ns->nsid);
 641         if (ns->nsid == subsys->max_nsid)
 642                 subsys->max_nsid = nvmet_max_nsid(subsys);
 643
 644         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 645                 pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
 646
 647         mutex_unlock(&subsys->lock);
 648
 649         /*
 650          * Now that we removed the namespaces from the lookup list, we
 651          * can kill the per_cpu ref and wait for any remaining references
 652          * to be dropped, as well as a RCU grace period for anyone only
 653          * using the namepace under rcu_read_lock().  Note that we can't
 654          * use call_rcu here as we need to ensure the namespaces have
 655          * been fully destroyed before unloading the module.
 656          */
 657         percpu_ref_kill(&ns->ref);
 658         synchronize_rcu();
 659         wait_for_completion(&ns->disable_done);
 660         percpu_ref_exit(&ns->ref);
 661
 662         mutex_lock(&subsys->lock);
 663
 664         subsys->nr_namespaces--;
 665         nvmet_ns_changed(subsys, ns->nsid);
 666         nvmet_ns_dev_disable(ns);
 667 out_unlock:
 668         mutex_unlock(&subsys->lock);
 669 }
 670
 671 void nvmet_ns_free(struct nvmet_ns *ns)
 672 {
 673         nvmet_ns_disable(ns);
 674
 675         down_write(&nvmet_ana_sem);
 676         nvmet_ana_group_enabled[ns->anagrpid]--;
 677         up_write(&nvmet_ana_sem);
 678
 679         kfree(ns->device_path);
 680         kfree(ns);
 681 }
 682
 683 struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid)
 684 {
 685         struct nvmet_ns *ns;
 686
 687         ns = kzalloc(sizeof(*ns), GFP_KERNEL);
 688         if (!ns)
 689                 return NULL;
 690
 691         init_completion(&ns->disable_done);
 692
 693         ns->nsid = nsid;
 694         ns->subsys = subsys;
 695
 696         down_write(&nvmet_ana_sem);
 697         ns->anagrpid = NVMET_DEFAULT_ANA_GRPID;
 698         nvmet_ana_group_enabled[ns->anagrpid]++;
 699         up_write(&nvmet_ana_sem);
 700
 701         uuid_gen(&ns->uuid);
 702         ns->buffered_io = false;
 703         ns->csi = NVME_CSI_NVM;
 704
 705         return ns;
 706 }
 707
 708 static void nvmet_update_sq_head(struct nvmet_req *req)
 709 {
 710         if (req->sq->size) {
 711                 u32 old_sqhd, new_sqhd;
 712
 713                 old_sqhd = READ_ONCE(req->sq->sqhd);
 714                 do {
 715                         new_sqhd = (old_sqhd + 1) % req->sq->size;
 716                 } while (!try_cmpxchg(&req->sq->sqhd, &old_sqhd, new_sqhd));
 717         }
 718         req->cqe->sq_head = cpu_to_le16(req->sq->sqhd & 0x0000FFFF);
 719 }
 720
 721 static void nvmet_set_error(struct nvmet_req *req, u16 status)
 722 {
 723         struct nvmet_ctrl *ctrl = req->sq->ctrl;
 724         struct nvme_error_slot *new_error_slot;
 725         unsigned long flags;
 726
 727         req->cqe->status = cpu_to_le16(status << 1);
 728
 729         if (!ctrl || req->error_loc == NVMET_NO_ERROR_LOC)
 730                 return;
 731
 732         spin_lock_irqsave(&ctrl->error_lock, flags);
 733         ctrl->err_counter++;
 734         new_error_slot =
 735                 &ctrl->slots[ctrl->err_counter % NVMET_ERROR_LOG_SLOTS];
 736
 737         new_error_slot->error_count = cpu_to_le64(ctrl->err_counter);
 738         new_error_slot->sqid = cpu_to_le16(req->sq->qid);
 739         new_error_slot->cmdid = cpu_to_le16(req->cmd->common.command_id);
 740         new_error_slot->status_field = cpu_to_le16(status << 1);
 741         new_error_slot->param_error_location = cpu_to_le16(req->error_loc);
 742         new_error_slot->lba = cpu_to_le64(req->error_slba);
 743         new_error_slot->nsid = req->cmd->common.nsid;
 744         spin_unlock_irqrestore(&ctrl->error_lock, flags);
 745
 746         /* set the more bit for this request */
 747         req->cqe->status |= cpu_to_le16(1 << 14);
 748 }
 749
 750 static void __nvmet_req_complete(struct nvmet_req *req, u16 status)
 751 {
 752         struct nvmet_ns *ns = req->ns;
 753
 754         if (!req->sq->sqhd_disabled)
 755                 nvmet_update_sq_head(req);
 756         req->cqe->sq_id = cpu_to_le16(req->sq->qid);
 757         req->cqe->command_id = req->cmd->common.command_id;
 758
 759         if (unlikely(status))
 760                 nvmet_set_error(req, status);
 761
 762         trace_nvmet_req_complete(req);
 763
 764         req->ops->queue_response(req);
 765         if (ns)
 766                 nvmet_put_namespace(ns);
 767 }
 768
 769 void nvmet_req_complete(struct nvmet_req *req, u16 status)
 770 {
 771         struct nvmet_sq *sq = req->sq;
 772
 773         __nvmet_req_complete(req, status);
 774         percpu_ref_put(&sq->ref);
 775 }
 776 EXPORT_SYMBOL_GPL(nvmet_req_complete);
 777
 778 void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq,
 779                 u16 qid, u16 size)
 780 {
 781         cq->qid = qid;
 782         cq->size = size;
 783 }
 784
 785 void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq,
 786                 u16 qid, u16 size)
 787 {
 788         sq->sqhd = 0;
 789         sq->qid = qid;
 790         sq->size = size;
 791
 792         ctrl->sqs[qid] = sq;
 793 }
 794
 795 static void nvmet_confirm_sq(struct percpu_ref *ref)
 796 {
 797         struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref);
 798
 799         complete(&sq->confirm_done);
 800 }
 801
 802 void nvmet_sq_destroy(struct nvmet_sq *sq)
 803 {
 804         struct nvmet_ctrl *ctrl = sq->ctrl;
 805
 806         /*
 807          * If this is the admin queue, complete all AERs so that our
 808          * queue doesn't have outstanding requests on it.
 809          */
 810         if (ctrl && ctrl->sqs && ctrl->sqs[0] == sq)
 811                 nvmet_async_events_failall(ctrl);
 812         percpu_ref_kill_and_confirm(&sq->ref, nvmet_confirm_sq);
 813         wait_for_completion(&sq->confirm_done);
 814         wait_for_completion(&sq->free_done);
 815         percpu_ref_exit(&sq->ref);
 816         nvmet_auth_sq_free(sq);
 817
 818         if (ctrl) {
 819                 /*
 820                  * The teardown flow may take some time, and the host may not
 821                  * send us keep-alive during this period, hence reset the
 822                  * traffic based keep-alive timer so we don't trigger a
 823                  * controller teardown as a result of a keep-alive expiration.
 824                  */
 825                 ctrl->reset_tbkas = true;
 826                 sq->ctrl->sqs[sq->qid] = NULL;
 827                 nvmet_ctrl_put(ctrl);
 828                 sq->ctrl = NULL; /* allows reusing the queue later */
 829         }
 830 }
 831 EXPORT_SYMBOL_GPL(nvmet_sq_destroy);
 832
 833 static void nvmet_sq_free(struct percpu_ref *ref)
 834 {
 835         struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref);
 836
 837         complete(&sq->free_done);
 838 }
 839
 840 int nvmet_sq_init(struct nvmet_sq *sq)
 841 {
 842         int ret;
 843
 844         ret = percpu_ref_init(&sq->ref, nvmet_sq_free, 0, GFP_KERNEL);
 845         if (ret) {
 846                 pr_err("percpu_ref init failed!\n");
 847                 return ret;
 848         }
 849         init_completion(&sq->free_done);
 850         init_completion(&sq->confirm_done);
 851         nvmet_auth_sq_init(sq);
 852
 853         return 0;
 854 }
 855 EXPORT_SYMBOL_GPL(nvmet_sq_init);
 856
 857 static inline u16 nvmet_check_ana_state(struct nvmet_port *port,
 858                 struct nvmet_ns *ns)
 859 {
 860         enum nvme_ana_state state = port->ana_state[ns->anagrpid];
 861
 862         if (unlikely(state == NVME_ANA_INACCESSIBLE))
 863                 return NVME_SC_ANA_INACCESSIBLE;
 864         if (unlikely(state == NVME_ANA_PERSISTENT_LOSS))
 865                 return NVME_SC_ANA_PERSISTENT_LOSS;
 866         if (unlikely(state == NVME_ANA_CHANGE))
 867                 return NVME_SC_ANA_TRANSITION;
 868         return 0;
 869 }
 870
 871 static inline u16 nvmet_io_cmd_check_access(struct nvmet_req *req)
 872 {
 873         if (unlikely(req->ns->readonly)) {
 874                 switch (req->cmd->common.opcode) {
 875                 case nvme_cmd_read:
 876                 case nvme_cmd_flush:
 877                         break;
 878                 default:
 879                         return NVME_SC_NS_WRITE_PROTECTED;
 880                 }
 881         }
 882
 883         return 0;
 884 }
 885
 886 static u16 nvmet_parse_io_cmd(struct nvmet_req *req)
 887 {
 888         struct nvme_command *cmd = req->cmd;
 889         u16 ret;
 890
 891         if (nvme_is_fabrics(cmd))
 892                 return nvmet_parse_fabrics_io_cmd(req);
 893
 894         if (unlikely(!nvmet_check_auth_status(req)))
 895                 return NVME_SC_AUTH_REQUIRED | NVME_SC_DNR;
 896
 897         ret = nvmet_check_ctrl_status(req);
 898         if (unlikely(ret))
 899                 return ret;
 900
 901         if (nvmet_is_passthru_req(req))
 902                 return nvmet_parse_passthru_io_cmd(req);
 903
 904         ret = nvmet_req_find_ns(req);
 905         if (unlikely(ret))
 906                 return ret;
 907
 908         ret = nvmet_check_ana_state(req->port, req->ns);
 909         if (unlikely(ret)) {
 910                 req->error_loc = offsetof(struct nvme_common_command, nsid);
 911                 return ret;
 912         }
 913         ret = nvmet_io_cmd_check_access(req);
 914         if (unlikely(ret)) {
 915                 req->error_loc = offsetof(struct nvme_common_command, nsid);
 916                 return ret;
 917         }
 918
 919         switch (req->ns->csi) {
 920         case NVME_CSI_NVM:
 921                 if (req->ns->file)
 922                         return nvmet_file_parse_io_cmd(req);
 923                 return nvmet_bdev_parse_io_cmd(req);
 924         case NVME_CSI_ZNS:
 925                 if (IS_ENABLED(CONFIG_BLK_DEV_ZONED))
 926                         return nvmet_bdev_zns_parse_io_cmd(req);
 927                 return NVME_SC_INVALID_IO_CMD_SET;
 928         default:
 929                 return NVME_SC_INVALID_IO_CMD_SET;
 930         }
 931 }
 932
 933 bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
 934                 struct nvmet_sq *sq, const struct nvmet_fabrics_ops *ops)
 935 {
 936         u8 flags = req->cmd->common.flags;
 937         u16 status;
 938
 939         req->cq = cq;
 940         req->sq = sq;
 941         req->ops = ops;
 942         req->sg = NULL;
 943         req->metadata_sg = NULL;
 944         req->sg_cnt = 0;
 945         req->metadata_sg_cnt = 0;
 946         req->transfer_len = 0;
 947         req->metadata_len = 0;
 948         req->cqe->status = 0;
 949         req->cqe->sq_head = 0;
 950         req->ns = NULL;
 951         req->error_loc = NVMET_NO_ERROR_LOC;
 952         req->error_slba = 0;
 953
 954         /* no support for fused commands yet */
 955         if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) {
 956                 req->error_loc = offsetof(struct nvme_common_command, flags);
 957                 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 958                 goto fail;
 959         }
 960
 961         /*
 962          * For fabrics, PSDT field shall describe metadata pointer (MPTR) that
 963          * contains an address of a single contiguous physical buffer that is
 964          * byte aligned.
 965          */
 966         if (unlikely((flags & NVME_CMD_SGL_ALL) != NVME_CMD_SGL_METABUF)) {
 967                 req->error_loc = offsetof(struct nvme_common_command, flags);
 968                 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 969                 goto fail;
 970         }
 971
 972         if (unlikely(!req->sq->ctrl))
 973                 /* will return an error for any non-connect command: */
 974                 status = nvmet_parse_connect_cmd(req);
 975         else if (likely(req->sq->qid != 0))
 976                 status = nvmet_parse_io_cmd(req);
 977         else
 978                 status = nvmet_parse_admin_cmd(req);
 979
 980         if (status)
 981                 goto fail;
 982
 983         trace_nvmet_req_init(req, req->cmd);
 984
 985         if (unlikely(!percpu_ref_tryget_live(&sq->ref))) {
 986                 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 987                 goto fail;
 988         }
 989
 990         if (sq->ctrl)
 991                 sq->ctrl->reset_tbkas = true;
 992
 993         return true;
 994
 995 fail:
 996         __nvmet_req_complete(req, status);
 997         return false;
 998 }
 999 EXPORT_SYMBOL_GPL(nvmet_req_init);
1000
1001 void nvmet_req_uninit(struct nvmet_req *req)
1002 {
1003         percpu_ref_put(&req->sq->ref);
1004         if (req->ns)
1005                 nvmet_put_namespace(req->ns);
1006 }
1007 EXPORT_SYMBOL_GPL(nvmet_req_uninit);
1008
1009 bool nvmet_check_transfer_len(struct nvmet_req *req, size_t len)
1010 {
1011         if (unlikely(len != req->transfer_len)) {
1012                 req->error_loc = offsetof(struct nvme_common_command, dptr);
1013                 nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR);
1014                 return false;
1015         }
1016
1017         return true;
1018 }
1019 EXPORT_SYMBOL_GPL(nvmet_check_transfer_len);
1020
1021 bool nvmet_check_data_len_lte(struct nvmet_req *req, size_t data_len)
1022 {
1023         if (unlikely(data_len > req->transfer_len)) {
1024                 req->error_loc = offsetof(struct nvme_common_command, dptr);
1025                 nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR);
1026                 return false;
1027         }
1028
1029         return true;
1030 }
1031
1032 static unsigned int nvmet_data_transfer_len(struct nvmet_req *req)
1033 {
1034         return req->transfer_len - req->metadata_len;
1035 }
1036
1037 static int nvmet_req_alloc_p2pmem_sgls(struct pci_dev *p2p_dev,
1038                 struct nvmet_req *req)
1039 {
1040         req->sg = pci_p2pmem_alloc_sgl(p2p_dev, &req->sg_cnt,
1041                         nvmet_data_transfer_len(req));
1042         if (!req->sg)
1043                 goto out_err;
1044
1045         if (req->metadata_len) {
1046                 req->metadata_sg = pci_p2pmem_alloc_sgl(p2p_dev,
1047                                 &req->metadata_sg_cnt, req->metadata_len);
1048                 if (!req->metadata_sg)
1049                         goto out_free_sg;
1050         }
1051
1052         req->p2p_dev = p2p_dev;
1053
1054         return 0;
1055 out_free_sg:
1056         pci_p2pmem_free_sgl(req->p2p_dev, req->sg);
1057 out_err:
1058         return -ENOMEM;
1059 }
1060
1061 static struct pci_dev *nvmet_req_find_p2p_dev(struct nvmet_req *req)
1062 {
1063         if (!IS_ENABLED(CONFIG_PCI_P2PDMA) ||
1064             !req->sq->ctrl || !req->sq->qid || !req->ns)
1065                 return NULL;
1066         return radix_tree_lookup(&req->sq->ctrl->p2p_ns_map, req->ns->nsid);
1067 }
1068
1069 int nvmet_req_alloc_sgls(struct nvmet_req *req)
1070 {
1071         struct pci_dev *p2p_dev = nvmet_req_find_p2p_dev(req);
1072
1073         if (p2p_dev && !nvmet_req_alloc_p2pmem_sgls(p2p_dev, req))
1074                 return 0;
1075
1076         req->sg = sgl_alloc(nvmet_data_transfer_len(req), GFP_KERNEL,
1077                             &req->sg_cnt);
1078         if (unlikely(!req->sg))
1079                 goto out;
1080
1081         if (req->metadata_len) {
1082                 req->metadata_sg = sgl_alloc(req->metadata_len, GFP_KERNEL,
1083                                              &req->metadata_sg_cnt);
1084                 if (unlikely(!req->metadata_sg))
1085                         goto out_free;
1086         }
1087
1088         return 0;
1089 out_free:
1090         sgl_free(req->sg);
1091 out:
1092         return -ENOMEM;
1093 }
1094 EXPORT_SYMBOL_GPL(nvmet_req_alloc_sgls);
1095
1096 void nvmet_req_free_sgls(struct nvmet_req *req)
1097 {
1098         if (req->p2p_dev) {
1099                 pci_p2pmem_free_sgl(req->p2p_dev, req->sg);
1100                 if (req->metadata_sg)
1101                         pci_p2pmem_free_sgl(req->p2p_dev, req->metadata_sg);
1102                 req->p2p_dev = NULL;
1103         } else {
1104                 sgl_free(req->sg);
1105                 if (req->metadata_sg)
1106                         sgl_free(req->metadata_sg);
1107         }
1108
1109         req->sg = NULL;
1110         req->metadata_sg = NULL;
1111         req->sg_cnt = 0;
1112         req->metadata_sg_cnt = 0;
1113 }
1114 EXPORT_SYMBOL_GPL(nvmet_req_free_sgls);
1115
1116 static inline bool nvmet_cc_en(u32 cc)
1117 {
1118         return (cc >> NVME_CC_EN_SHIFT) & 0x1;
1119 }
1120
1121 static inline u8 nvmet_cc_css(u32 cc)
1122 {
1123         return (cc >> NVME_CC_CSS_SHIFT) & 0x7;
1124 }
1125
1126 static inline u8 nvmet_cc_mps(u32 cc)
1127 {
1128         return (cc >> NVME_CC_MPS_SHIFT) & 0xf;
1129 }
1130
1131 static inline u8 nvmet_cc_ams(u32 cc)
1132 {
1133         return (cc >> NVME_CC_AMS_SHIFT) & 0x7;
1134 }
1135
1136 static inline u8 nvmet_cc_shn(u32 cc)
1137 {
1138         return (cc >> NVME_CC_SHN_SHIFT) & 0x3;
1139 }
1140
1141 static inline u8 nvmet_cc_iosqes(u32 cc)
1142 {
1143         return (cc >> NVME_CC_IOSQES_SHIFT) & 0xf;
1144 }
1145
1146 static inline u8 nvmet_cc_iocqes(u32 cc)
1147 {
1148         return (cc >> NVME_CC_IOCQES_SHIFT) & 0xf;
1149 }
1150
1151 static inline bool nvmet_css_supported(u8 cc_css)
1152 {
1153         switch (cc_css << NVME_CC_CSS_SHIFT) {
1154         case NVME_CC_CSS_NVM:
1155         case NVME_CC_CSS_CSI:
1156                 return true;
1157         default:
1158                 return false;
1159         }
1160 }
1161
1162 static void nvmet_start_ctrl(struct nvmet_ctrl *ctrl)
1163 {
1164         lockdep_assert_held(&ctrl->lock);
1165
1166         /*
1167          * Only I/O controllers should verify iosqes,iocqes.
1168          * Strictly speaking, the spec says a discovery controller
1169          * should verify iosqes,iocqes are zeroed, however that
1170          * would break backwards compatibility, so don't enforce it.
1171          */
1172         if (!nvmet_is_disc_subsys(ctrl->subsys) &&
1173             (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES ||
1174              nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES)) {
1175                 ctrl->csts = NVME_CSTS_CFS;
1176                 return;
1177         }
1178
1179         if (nvmet_cc_mps(ctrl->cc) != 0 ||
1180             nvmet_cc_ams(ctrl->cc) != 0 ||
1181             !nvmet_css_supported(nvmet_cc_css(ctrl->cc))) {
1182                 ctrl->csts = NVME_CSTS_CFS;
1183                 return;
1184         }
1185
1186         ctrl->csts = NVME_CSTS_RDY;
1187
1188         /*
1189          * Controllers that are not yet enabled should not really enforce the
1190          * keep alive timeout, but we still want to track a timeout and cleanup
1191          * in case a host died before it enabled the controller.  Hence, simply
1192          * reset the keep alive timer when the controller is enabled.
1193          */
1194         if (ctrl->kato)
1195                 mod_delayed_work(nvmet_wq, &ctrl->ka_work, ctrl->kato * HZ);
1196 }
1197
1198 static void nvmet_clear_ctrl(struct nvmet_ctrl *ctrl)
1199 {
1200         lockdep_assert_held(&ctrl->lock);
1201
1202         /* XXX: tear down queues? */
1203         ctrl->csts &= ~NVME_CSTS_RDY;
1204         ctrl->cc = 0;
1205 }
1206
1207 void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new)
1208 {
1209         u32 old;
1210
1211         mutex_lock(&ctrl->lock);
1212         old = ctrl->cc;
1213         ctrl->cc = new;
1214
1215         if (nvmet_cc_en(new) && !nvmet_cc_en(old))
1216                 nvmet_start_ctrl(ctrl);
1217         if (!nvmet_cc_en(new) && nvmet_cc_en(old))
1218                 nvmet_clear_ctrl(ctrl);
1219         if (nvmet_cc_shn(new) && !nvmet_cc_shn(old)) {
1220                 nvmet_clear_ctrl(ctrl);
1221                 ctrl->csts |= NVME_CSTS_SHST_CMPLT;
1222         }
1223         if (!nvmet_cc_shn(new) && nvmet_cc_shn(old))
1224                 ctrl->csts &= ~NVME_CSTS_SHST_CMPLT;
1225         mutex_unlock(&ctrl->lock);
1226 }
1227
1228 static void nvmet_init_cap(struct nvmet_ctrl *ctrl)
1229 {
1230         /* command sets supported: NVMe command set: */
1231         ctrl->cap = (1ULL << 37);
1232         /* Controller supports one or more I/O Command Sets */
1233         ctrl->cap |= (1ULL << 43);
1234         /* CC.EN timeout in 500msec units: */
1235         ctrl->cap |= (15ULL << 24);
1236         /* maximum queue entries supported: */
1237         if (ctrl->ops->get_max_queue_size)
1238                 ctrl->cap |= min_t(u16, ctrl->ops->get_max_queue_size(ctrl),
1239                                    ctrl->port->max_queue_size) - 1;
1240         else
1241                 ctrl->cap |= ctrl->port->max_queue_size - 1;
1242
1243         if (nvmet_is_passthru_subsys(ctrl->subsys))
1244                 nvmet_passthrough_override_cap(ctrl);
1245 }
1246
1247 struct nvmet_ctrl *nvmet_ctrl_find_get(const char *subsysnqn,
1248                                        const char *hostnqn, u16 cntlid,
1249                                        struct nvmet_req *req)
1250 {
1251         struct nvmet_ctrl *ctrl = NULL;
1252         struct nvmet_subsys *subsys;
1253
1254         subsys = nvmet_find_get_subsys(req->port, subsysnqn);
1255         if (!subsys) {
1256                 pr_warn("connect request for invalid subsystem %s!\n",
1257                         subsysnqn);
1258                 req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn);
1259                 goto out;
1260         }
1261
1262         mutex_lock(&subsys->lock);
1263         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
1264                 if (ctrl->cntlid == cntlid) {
1265                         if (strncmp(hostnqn, ctrl->hostnqn, NVMF_NQN_SIZE)) {
1266                                 pr_warn("hostnqn mismatch.\n");
1267                                 continue;
1268                         }
1269                         if (!kref_get_unless_zero(&ctrl->ref))
1270                                 continue;
1271
1272                         /* ctrl found */
1273                         goto found;
1274                 }
1275         }
1276
1277         ctrl = NULL; /* ctrl not found */
1278         pr_warn("could not find controller %d for subsys %s / host %s\n",
1279                 cntlid, subsysnqn, hostnqn);
1280         req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(cntlid);
1281
1282 found:
1283         mutex_unlock(&subsys->lock);
1284         nvmet_subsys_put(subsys);
1285 out:
1286         return ctrl;
1287 }
1288
1289 u16 nvmet_check_ctrl_status(struct nvmet_req *req)
1290 {
1291         if (unlikely(!(req->sq->ctrl->cc & NVME_CC_ENABLE))) {
1292                 pr_err("got cmd %d while CC.EN == 0 on qid = %d\n",
1293                        req->cmd->common.opcode, req->sq->qid);
1294                 return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
1295         }
1296
1297         if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
1298                 pr_err("got cmd %d while CSTS.RDY == 0 on qid = %d\n",
1299                        req->cmd->common.opcode, req->sq->qid);
1300                 return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
1301         }
1302
1303         if (unlikely(!nvmet_check_auth_status(req))) {
1304                 pr_warn("qid %d not authenticated\n", req->sq->qid);
1305                 return NVME_SC_AUTH_REQUIRED | NVME_SC_DNR;
1306         }
1307         return 0;
1308 }
1309
1310 bool nvmet_host_allowed(struct nvmet_subsys *subsys, const char *hostnqn)
1311 {
1312         struct nvmet_host_link *p;
1313
1314         lockdep_assert_held(&nvmet_config_sem);
1315
1316         if (subsys->allow_any_host)
1317                 return true;
1318
1319         if (nvmet_is_disc_subsys(subsys)) /* allow all access to disc subsys */
1320                 return true;
1321
1322         list_for_each_entry(p, &subsys->hosts, entry) {
1323                 if (!strcmp(nvmet_host_name(p->host), hostnqn))
1324                         return true;
1325         }
1326
1327         return false;
1328 }
1329
1330 /*
1331  * Note: ctrl->subsys->lock should be held when calling this function
1332  */
1333 static void nvmet_setup_p2p_ns_map(struct nvmet_ctrl *ctrl,
1334                 struct nvmet_req *req)
1335 {
1336         struct nvmet_ns *ns;
1337         unsigned long idx;
1338
1339         if (!req->p2p_client)
1340                 return;
1341
1342         ctrl->p2p_client = get_device(req->p2p_client);
1343
1344         xa_for_each(&ctrl->subsys->namespaces, idx, ns)
1345                 nvmet_p2pmem_ns_add_p2p(ctrl, ns);
1346 }
1347
1348 /*
1349  * Note: ctrl->subsys->lock should be held when calling this function
1350  */
1351 static void nvmet_release_p2p_ns_map(struct nvmet_ctrl *ctrl)
1352 {
1353         struct radix_tree_iter iter;
1354         void __rcu **slot;
1355
1356         radix_tree_for_each_slot(slot, &ctrl->p2p_ns_map, &iter, 0)
1357                 pci_dev_put(radix_tree_deref_slot(slot));
1358
1359         put_device(ctrl->p2p_client);
1360 }
1361
1362 static void nvmet_fatal_error_handler(struct work_struct *work)
1363 {
1364         struct nvmet_ctrl *ctrl =
1365                         container_of(work, struct nvmet_ctrl, fatal_err_work);
1366
1367         pr_err("ctrl %d fatal error occurred!\n", ctrl->cntlid);
1368         ctrl->ops->delete_ctrl(ctrl);
1369 }
1370
1371 u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
1372                 struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp)
1373 {
1374         struct nvmet_subsys *subsys;
1375         struct nvmet_ctrl *ctrl;
1376         int ret;
1377         u16 status;
1378
1379         status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1380         subsys = nvmet_find_get_subsys(req->port, subsysnqn);
1381         if (!subsys) {
1382                 pr_warn("connect request for invalid subsystem %s!\n",
1383                         subsysnqn);
1384                 req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn);
1385                 req->error_loc = offsetof(struct nvme_common_command, dptr);
1386                 goto out;
1387         }
1388
1389         down_read(&nvmet_config_sem);
1390         if (!nvmet_host_allowed(subsys, hostnqn)) {
1391                 pr_info("connect by host %s for subsystem %s not allowed\n",
1392                         hostnqn, subsysnqn);
1393                 req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(hostnqn);
1394                 up_read(&nvmet_config_sem);
1395                 status = NVME_SC_CONNECT_INVALID_HOST | NVME_SC_DNR;
1396                 req->error_loc = offsetof(struct nvme_common_command, dptr);
1397                 goto out_put_subsystem;
1398         }
1399         up_read(&nvmet_config_sem);
1400
1401         status = NVME_SC_INTERNAL;
1402         ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
1403         if (!ctrl)
1404                 goto out_put_subsystem;
1405         mutex_init(&ctrl->lock);
1406
1407         ctrl->port = req->port;
1408         ctrl->ops = req->ops;
1409
1410 #ifdef CONFIG_NVME_TARGET_PASSTHRU
1411         /* By default, set loop targets to clear IDS by default */
1412         if (ctrl->port->disc_addr.trtype == NVMF_TRTYPE_LOOP)
1413                 subsys->clear_ids = 1;
1414 #endif
1415
1416         INIT_WORK(&ctrl->async_event_work, nvmet_async_event_work);
1417         INIT_LIST_HEAD(&ctrl->async_events);
1418         INIT_RADIX_TREE(&ctrl->p2p_ns_map, GFP_KERNEL);
1419         INIT_WORK(&ctrl->fatal_err_work, nvmet_fatal_error_handler);
1420         INIT_DELAYED_WORK(&ctrl->ka_work, nvmet_keep_alive_timer);
1421
1422         memcpy(ctrl->subsysnqn, subsysnqn, NVMF_NQN_SIZE);
1423         memcpy(ctrl->hostnqn, hostnqn, NVMF_NQN_SIZE);
1424
1425         kref_init(&ctrl->ref);
1426         ctrl->subsys = subsys;
1427         ctrl->pi_support = ctrl->port->pi_enable && ctrl->subsys->pi_support;
1428         nvmet_init_cap(ctrl);
1429         WRITE_ONCE(ctrl->aen_enabled, NVMET_AEN_CFG_OPTIONAL);
1430
1431         ctrl->changed_ns_list = kmalloc_array(NVME_MAX_CHANGED_NAMESPACES,
1432                         sizeof(__le32), GFP_KERNEL);
1433         if (!ctrl->changed_ns_list)
1434                 goto out_free_ctrl;
1435
1436         ctrl->sqs = kcalloc(subsys->max_qid + 1,
1437                         sizeof(struct nvmet_sq *),
1438                         GFP_KERNEL);
1439         if (!ctrl->sqs)
1440                 goto out_free_changed_ns_list;
1441
1442         ret = ida_alloc_range(&cntlid_ida,
1443                              subsys->cntlid_min, subsys->cntlid_max,
1444                              GFP_KERNEL);
1445         if (ret < 0) {
1446                 status = NVME_SC_CONNECT_CTRL_BUSY | NVME_SC_DNR;
1447                 goto out_free_sqs;
1448         }
1449         ctrl->cntlid = ret;
1450
1451         /*
1452          * Discovery controllers may use some arbitrary high value
1453          * in order to cleanup stale discovery sessions
1454          */
1455         if (nvmet_is_disc_subsys(ctrl->subsys) && !kato)
1456                 kato = NVMET_DISC_KATO_MS;
1457
1458         /* keep-alive timeout in seconds */
1459         ctrl->kato = DIV_ROUND_UP(kato, 1000);
1460
1461         ctrl->err_counter = 0;
1462         spin_lock_init(&ctrl->error_lock);
1463
1464         nvmet_start_keep_alive_timer(ctrl);
1465
1466         mutex_lock(&subsys->lock);
1467         list_add_tail(&ctrl->subsys_entry, &subsys->ctrls);
1468         nvmet_setup_p2p_ns_map(ctrl, req);
1469         mutex_unlock(&subsys->lock);
1470
1471         *ctrlp = ctrl;
1472         return 0;
1473
1474 out_free_sqs:
1475         kfree(ctrl->sqs);
1476 out_free_changed_ns_list:
1477         kfree(ctrl->changed_ns_list);
1478 out_free_ctrl:
1479         kfree(ctrl);
1480 out_put_subsystem:
1481         nvmet_subsys_put(subsys);
1482 out:
1483         return status;
1484 }
1485
1486 static void nvmet_ctrl_free(struct kref *ref)
1487 {
1488         struct nvmet_ctrl *ctrl = container_of(ref, struct nvmet_ctrl, ref);
1489         struct nvmet_subsys *subsys = ctrl->subsys;
1490
1491         mutex_lock(&subsys->lock);
1492         nvmet_release_p2p_ns_map(ctrl);
1493         list_del(&ctrl->subsys_entry);
1494         mutex_unlock(&subsys->lock);
1495
1496         nvmet_stop_keep_alive_timer(ctrl);
1497
1498         flush_work(&ctrl->async_event_work);
1499         cancel_work_sync(&ctrl->fatal_err_work);
1500
1501         nvmet_destroy_auth(ctrl);
1502
1503         ida_free(&cntlid_ida, ctrl->cntlid);
1504
1505         nvmet_async_events_free(ctrl);
1506         kfree(ctrl->sqs);
1507         kfree(ctrl->changed_ns_list);
1508         kfree(ctrl);
1509
1510         nvmet_subsys_put(subsys);
1511 }
1512
1513 void nvmet_ctrl_put(struct nvmet_ctrl *ctrl)
1514 {
1515         kref_put(&ctrl->ref, nvmet_ctrl_free);
1516 }
1517
1518 void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl)
1519 {
1520         mutex_lock(&ctrl->lock);
1521         if (!(ctrl->csts & NVME_CSTS_CFS)) {
1522                 ctrl->csts |= NVME_CSTS_CFS;
1523                 queue_work(nvmet_wq, &ctrl->fatal_err_work);
1524         }
1525         mutex_unlock(&ctrl->lock);
1526 }
1527 EXPORT_SYMBOL_GPL(nvmet_ctrl_fatal_error);
1528
1529 static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
1530                 const char *subsysnqn)
1531 {
1532         struct nvmet_subsys_link *p;
1533
1534         if (!port)
1535                 return NULL;
1536
1537         if (!strcmp(NVME_DISC_SUBSYS_NAME, subsysnqn)) {
1538                 if (!kref_get_unless_zero(&nvmet_disc_subsys->ref))
1539                         return NULL;
1540                 return nvmet_disc_subsys;
1541         }
1542
1543         down_read(&nvmet_config_sem);
1544         list_for_each_entry(p, &port->subsystems, entry) {
1545                 if (!strncmp(p->subsys->subsysnqn, subsysnqn,
1546                                 NVMF_NQN_SIZE)) {
1547                         if (!kref_get_unless_zero(&p->subsys->ref))
1548                                 break;
1549                         up_read(&nvmet_config_sem);
1550                         return p->subsys;
1551                 }
1552         }
1553         up_read(&nvmet_config_sem);
1554         return NULL;
1555 }
1556
1557 struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
1558                 enum nvme_subsys_type type)
1559 {
1560         struct nvmet_subsys *subsys;
1561         char serial[NVMET_SN_MAX_SIZE / 2];
1562         int ret;
1563
1564         subsys = kzalloc(sizeof(*subsys), GFP_KERNEL);
1565         if (!subsys)
1566                 return ERR_PTR(-ENOMEM);
1567
1568         subsys->ver = NVMET_DEFAULT_VS;
1569         /* generate a random serial number as our controllers are ephemeral: */
1570         get_random_bytes(&serial, sizeof(serial));
1571         bin2hex(subsys->serial, &serial, sizeof(serial));
1572
1573         subsys->model_number = kstrdup(NVMET_DEFAULT_CTRL_MODEL, GFP_KERNEL);
1574         if (!subsys->model_number) {
1575                 ret = -ENOMEM;
1576                 goto free_subsys;
1577         }
1578
1579         subsys->ieee_oui = 0;
1580
1581         subsys->firmware_rev = kstrndup(UTS_RELEASE, NVMET_FR_MAX_SIZE, GFP_KERNEL);
1582         if (!subsys->firmware_rev) {
1583                 ret = -ENOMEM;
1584                 goto free_mn;
1585         }
1586
1587         switch (type) {
1588         case NVME_NQN_NVME:
1589                 subsys->max_qid = NVMET_NR_QUEUES;
1590                 break;
1591         case NVME_NQN_DISC:
1592         case NVME_NQN_CURR:
1593                 subsys->max_qid = 0;
1594                 break;
1595         default:
1596                 pr_err("%s: Unknown Subsystem type - %d\n", __func__, type);
1597                 ret = -EINVAL;
1598                 goto free_fr;
1599         }
1600         subsys->type = type;
1601         subsys->subsysnqn = kstrndup(subsysnqn, NVMF_NQN_SIZE,
1602                         GFP_KERNEL);
1603         if (!subsys->subsysnqn) {
1604                 ret = -ENOMEM;
1605                 goto free_fr;
1606         }
1607         subsys->cntlid_min = NVME_CNTLID_MIN;
1608         subsys->cntlid_max = NVME_CNTLID_MAX;
1609         kref_init(&subsys->ref);
1610
1611         mutex_init(&subsys->lock);
1612         xa_init(&subsys->namespaces);
1613         INIT_LIST_HEAD(&subsys->ctrls);
1614         INIT_LIST_HEAD(&subsys->hosts);
1615
1616         return subsys;
1617
1618 free_fr:
1619         kfree(subsys->firmware_rev);
1620 free_mn:
1621         kfree(subsys->model_number);
1622 free_subsys:
1623         kfree(subsys);
1624         return ERR_PTR(ret);
1625 }
1626
1627 static void nvmet_subsys_free(struct kref *ref)
1628 {
1629         struct nvmet_subsys *subsys =
1630                 container_of(ref, struct nvmet_subsys, ref);
1631
1632         WARN_ON_ONCE(!xa_empty(&subsys->namespaces));
1633
1634         xa_destroy(&subsys->namespaces);
1635         nvmet_passthru_subsys_free(subsys);
1636
1637         kfree(subsys->subsysnqn);
1638         kfree(subsys->model_number);
1639         kfree(subsys->firmware_rev);
1640         kfree(subsys);
1641 }
1642
1643 void nvmet_subsys_del_ctrls(struct nvmet_subsys *subsys)
1644 {
1645         struct nvmet_ctrl *ctrl;
1646
1647         mutex_lock(&subsys->lock);
1648         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
1649                 ctrl->ops->delete_ctrl(ctrl);
1650         mutex_unlock(&subsys->lock);
1651 }
1652
1653 void nvmet_subsys_put(struct nvmet_subsys *subsys)
1654 {
1655         kref_put(&subsys->ref, nvmet_subsys_free);
1656 }
1657
1658 static int __init nvmet_init(void)
1659 {
1660         int error = -ENOMEM;
1661
1662         nvmet_ana_group_enabled[NVMET_DEFAULT_ANA_GRPID] = 1;
1663
1664         nvmet_bvec_cache = kmem_cache_create("nvmet-bvec",
1665                         NVMET_MAX_MPOOL_BVEC * sizeof(struct bio_vec), 0,
1666                         SLAB_HWCACHE_ALIGN, NULL);
1667         if (!nvmet_bvec_cache)
1668                 return -ENOMEM;
1669
1670         zbd_wq = alloc_workqueue("nvmet-zbd-wq", WQ_MEM_RECLAIM, 0);
1671         if (!zbd_wq)
1672                 goto out_destroy_bvec_cache;
1673
1674         buffered_io_wq = alloc_workqueue("nvmet-buffered-io-wq",
1675                         WQ_MEM_RECLAIM, 0);
1676         if (!buffered_io_wq)
1677                 goto out_free_zbd_work_queue;
1678
1679         nvmet_wq = alloc_workqueue("nvmet-wq", WQ_MEM_RECLAIM, 0);
1680         if (!nvmet_wq)
1681                 goto out_free_buffered_work_queue;
1682
1683         error = nvmet_init_discovery();
1684         if (error)
1685                 goto out_free_nvmet_work_queue;
1686
1687         error = nvmet_init_configfs();
1688         if (error)
1689                 goto out_exit_discovery;
1690         return 0;
1691
1692 out_exit_discovery:
1693         nvmet_exit_discovery();
1694 out_free_nvmet_work_queue:
1695         destroy_workqueue(nvmet_wq);
1696 out_free_buffered_work_queue:
1697         destroy_workqueue(buffered_io_wq);
1698 out_free_zbd_work_queue:
1699         destroy_workqueue(zbd_wq);
1700 out_destroy_bvec_cache:
1701         kmem_cache_destroy(nvmet_bvec_cache);
1702         return error;
1703 }
1704
1705 static void __exit nvmet_exit(void)
1706 {
1707         nvmet_exit_configfs();
1708         nvmet_exit_discovery();
1709         ida_destroy(&cntlid_ida);
1710         destroy_workqueue(nvmet_wq);
1711         destroy_workqueue(buffered_io_wq);
1712         destroy_workqueue(zbd_wq);
1713         kmem_cache_destroy(nvmet_bvec_cache);
1714
1715         BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_entry) != 1024);
1716         BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_hdr) != 1024);
1717 }
1718
1719 module_init(nvmet_init);
1720 module_exit(nvmet_exit);
1721
1722 MODULE_DESCRIPTION("NVMe target core framework");
1723 MODULE_LICENSE("GPL v2");