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   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
  20struct kmem_cache *nvmet_bvec_cache;
  21struct workqueue_struct *buffered_io_wq;
  22struct workqueue_struct *zbd_wq;
  23static const struct nvmet_fabrics_ops *nvmet_transports[NVMF_TRTYPE_MAX];
  24static DEFINE_IDA(cntlid_ida);
  25
  26struct workqueue_struct *nvmet_wq;
  27EXPORT_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 */
  45DECLARE_RWSEM(nvmet_config_sem);
  46
  47u32 nvmet_ana_group_enabled[NVMET_MAX_ANAGRPS + 1];
  48u64 nvmet_ana_chgcnt;
  49DECLARE_RWSEM(nvmet_ana_sem);
  50
  51inline 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
  83u16 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
  92static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
  93		const char *subsysnqn);
  94
  95u16 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
 105u16 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
 114u16 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
 123static 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
 135static 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
 140static 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
 154static 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
 177static 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
 189static 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
 197void 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
 217static 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;
 237out_unlock:
 238	mutex_unlock(&ctrl->lock);
 239}
 240
 241void 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
 257void 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
 274void 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
 284int 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}
 297EXPORT_SYMBOL_GPL(nvmet_register_transport);
 298
 299void 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}
 305EXPORT_SYMBOL_GPL(nvmet_unregister_transport);
 306
 307void 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
 319int 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
 377out_put:
 378	module_put(ops->owner);
 379	return ret;
 380}
 381
 382void 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
 396static 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
 416void 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
 427void 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
 437u16 nvmet_req_find_ns(struct nvmet_req *req)
 438{
 439	u32 nsid = le32_to_cpu(req->cmd->common.nsid);
 440	struct nvmet_subsys *subsys = nvmet_req_subsys(req);
 441
 442	req->ns = xa_load(&subsys->namespaces, nsid);
 443	if (unlikely(!req->ns)) {
 444		req->error_loc = offsetof(struct nvme_common_command, nsid);
 445		if (nvmet_subsys_nsid_exists(subsys, nsid))
 446			return NVME_SC_INTERNAL_PATH_ERROR;
 447		return NVME_SC_INVALID_NS | NVME_SC_DNR;
 448	}
 449
 450	percpu_ref_get(&req->ns->ref);
 451	return NVME_SC_SUCCESS;
 452}
 453
 454static void nvmet_destroy_namespace(struct percpu_ref *ref)
 455{
 456	struct nvmet_ns *ns = container_of(ref, struct nvmet_ns, ref);
 457
 458	complete(&ns->disable_done);
 459}
 460
 461void nvmet_put_namespace(struct nvmet_ns *ns)
 462{
 463	percpu_ref_put(&ns->ref);
 464}
 465
 466static void nvmet_ns_dev_disable(struct nvmet_ns *ns)
 467{
 468	nvmet_bdev_ns_disable(ns);
 469	nvmet_file_ns_disable(ns);
 470}
 471
 472static int nvmet_p2pmem_ns_enable(struct nvmet_ns *ns)
 473{
 474	int ret;
 475	struct pci_dev *p2p_dev;
 476
 477	if (!ns->use_p2pmem)
 478		return 0;
 479
 480	if (!ns->bdev) {
 481		pr_err("peer-to-peer DMA is not supported by non-block device namespaces\n");
 482		return -EINVAL;
 483	}
 484
 485	if (!blk_queue_pci_p2pdma(ns->bdev->bd_disk->queue)) {
 486		pr_err("peer-to-peer DMA is not supported by the driver of %s\n",
 487		       ns->device_path);
 488		return -EINVAL;
 489	}
 490
 491	if (ns->p2p_dev) {
 492		ret = pci_p2pdma_distance(ns->p2p_dev, nvmet_ns_dev(ns), true);
 493		if (ret < 0)
 494			return -EINVAL;
 495	} else {
 496		/*
 497		 * Right now we just check that there is p2pmem available so
 498		 * we can report an error to the user right away if there
 499		 * is not. We'll find the actual device to use once we
 500		 * setup the controller when the port's device is available.
 501		 */
 502
 503		p2p_dev = pci_p2pmem_find(nvmet_ns_dev(ns));
 504		if (!p2p_dev) {
 505			pr_err("no peer-to-peer memory is available for %s\n",
 506			       ns->device_path);
 507			return -EINVAL;
 508		}
 509
 510		pci_dev_put(p2p_dev);
 511	}
 512
 513	return 0;
 514}
 515
 516/*
 517 * Note: ctrl->subsys->lock should be held when calling this function
 518 */
 519static void nvmet_p2pmem_ns_add_p2p(struct nvmet_ctrl *ctrl,
 520				    struct nvmet_ns *ns)
 521{
 522	struct device *clients[2];
 523	struct pci_dev *p2p_dev;
 524	int ret;
 525
 526	if (!ctrl->p2p_client || !ns->use_p2pmem)
 527		return;
 528
 529	if (ns->p2p_dev) {
 530		ret = pci_p2pdma_distance(ns->p2p_dev, ctrl->p2p_client, true);
 531		if (ret < 0)
 532			return;
 533
 534		p2p_dev = pci_dev_get(ns->p2p_dev);
 535	} else {
 536		clients[0] = ctrl->p2p_client;
 537		clients[1] = nvmet_ns_dev(ns);
 538
 539		p2p_dev = pci_p2pmem_find_many(clients, ARRAY_SIZE(clients));
 540		if (!p2p_dev) {
 541			pr_err("no peer-to-peer memory is available that's supported by %s and %s\n",
 542			       dev_name(ctrl->p2p_client), ns->device_path);
 543			return;
 544		}
 545	}
 546
 547	ret = radix_tree_insert(&ctrl->p2p_ns_map, ns->nsid, p2p_dev);
 548	if (ret < 0)
 549		pci_dev_put(p2p_dev);
 550
 551	pr_info("using p2pmem on %s for nsid %d\n", pci_name(p2p_dev),
 552		ns->nsid);
 553}
 554
 555bool nvmet_ns_revalidate(struct nvmet_ns *ns)
 556{
 557	loff_t oldsize = ns->size;
 558
 559	if (ns->bdev)
 560		nvmet_bdev_ns_revalidate(ns);
 561	else
 562		nvmet_file_ns_revalidate(ns);
 563
 564	return oldsize != ns->size;
 565}
 566
 567int nvmet_ns_enable(struct nvmet_ns *ns)
 568{
 569	struct nvmet_subsys *subsys = ns->subsys;
 570	struct nvmet_ctrl *ctrl;
 571	int ret;
 572
 573	mutex_lock(&subsys->lock);
 574	ret = 0;
 575
 576	if (nvmet_is_passthru_subsys(subsys)) {
 577		pr_info("cannot enable both passthru and regular namespaces for a single subsystem");
 578		goto out_unlock;
 579	}
 580
 581	if (ns->enabled)
 582		goto out_unlock;
 583
 584	ret = -EMFILE;
 585	if (subsys->nr_namespaces == NVMET_MAX_NAMESPACES)
 586		goto out_unlock;
 587
 588	ret = nvmet_bdev_ns_enable(ns);
 589	if (ret == -ENOTBLK)
 590		ret = nvmet_file_ns_enable(ns);
 591	if (ret)
 592		goto out_unlock;
 593
 594	ret = nvmet_p2pmem_ns_enable(ns);
 595	if (ret)
 596		goto out_dev_disable;
 597
 598	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 599		nvmet_p2pmem_ns_add_p2p(ctrl, ns);
 600
 601	ret = percpu_ref_init(&ns->ref, nvmet_destroy_namespace,
 602				0, GFP_KERNEL);
 603	if (ret)
 604		goto out_dev_put;
 605
 606	if (ns->nsid > subsys->max_nsid)
 607		subsys->max_nsid = ns->nsid;
 608
 609	ret = xa_insert(&subsys->namespaces, ns->nsid, ns, GFP_KERNEL);
 610	if (ret)
 611		goto out_restore_subsys_maxnsid;
 612
 613	subsys->nr_namespaces++;
 614
 615	nvmet_ns_changed(subsys, ns->nsid);
 616	ns->enabled = true;
 617	ret = 0;
 618out_unlock:
 619	mutex_unlock(&subsys->lock);
 620	return ret;
 621
 622out_restore_subsys_maxnsid:
 623	subsys->max_nsid = nvmet_max_nsid(subsys);
 624	percpu_ref_exit(&ns->ref);
 625out_dev_put:
 626	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 627		pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
 628out_dev_disable:
 629	nvmet_ns_dev_disable(ns);
 630	goto out_unlock;
 631}
 632
 633void nvmet_ns_disable(struct nvmet_ns *ns)
 634{
 635	struct nvmet_subsys *subsys = ns->subsys;
 636	struct nvmet_ctrl *ctrl;
 637
 638	mutex_lock(&subsys->lock);
 639	if (!ns->enabled)
 640		goto out_unlock;
 641
 642	ns->enabled = false;
 643	xa_erase(&ns->subsys->namespaces, ns->nsid);
 644	if (ns->nsid == subsys->max_nsid)
 645		subsys->max_nsid = nvmet_max_nsid(subsys);
 646
 647	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
 648		pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
 649
 650	mutex_unlock(&subsys->lock);
 651
 652	/*
 653	 * Now that we removed the namespaces from the lookup list, we
 654	 * can kill the per_cpu ref and wait for any remaining references
 655	 * to be dropped, as well as a RCU grace period for anyone only
 656	 * using the namepace under rcu_read_lock().  Note that we can't
 657	 * use call_rcu here as we need to ensure the namespaces have
 658	 * been fully destroyed before unloading the module.
 659	 */
 660	percpu_ref_kill(&ns->ref);
 661	synchronize_rcu();
 662	wait_for_completion(&ns->disable_done);
 663	percpu_ref_exit(&ns->ref);
 664
 665	mutex_lock(&subsys->lock);
 666
 667	subsys->nr_namespaces--;
 668	nvmet_ns_changed(subsys, ns->nsid);
 669	nvmet_ns_dev_disable(ns);
 670out_unlock:
 671	mutex_unlock(&subsys->lock);
 672}
 673
 674void nvmet_ns_free(struct nvmet_ns *ns)
 675{
 676	nvmet_ns_disable(ns);
 677
 678	down_write(&nvmet_ana_sem);
 679	nvmet_ana_group_enabled[ns->anagrpid]--;
 680	up_write(&nvmet_ana_sem);
 681
 682	kfree(ns->device_path);
 683	kfree(ns);
 684}
 685
 686struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid)
 687{
 688	struct nvmet_ns *ns;
 689
 690	ns = kzalloc(sizeof(*ns), GFP_KERNEL);
 691	if (!ns)
 692		return NULL;
 693
 694	init_completion(&ns->disable_done);
 695
 696	ns->nsid = nsid;
 697	ns->subsys = subsys;
 698
 699	down_write(&nvmet_ana_sem);
 700	ns->anagrpid = NVMET_DEFAULT_ANA_GRPID;
 701	nvmet_ana_group_enabled[ns->anagrpid]++;
 702	up_write(&nvmet_ana_sem);
 703
 704	uuid_gen(&ns->uuid);
 705	ns->buffered_io = false;
 706	ns->csi = NVME_CSI_NVM;
 707
 708	return ns;
 709}
 710
 711static void nvmet_update_sq_head(struct nvmet_req *req)
 712{
 713	if (req->sq->size) {
 714		u32 old_sqhd, new_sqhd;
 715
 716		old_sqhd = READ_ONCE(req->sq->sqhd);
 717		do {
 718			new_sqhd = (old_sqhd + 1) % req->sq->size;
 719		} while (!try_cmpxchg(&req->sq->sqhd, &old_sqhd, new_sqhd));
 720	}
 721	req->cqe->sq_head = cpu_to_le16(req->sq->sqhd & 0x0000FFFF);
 722}
 723
 724static void nvmet_set_error(struct nvmet_req *req, u16 status)
 725{
 726	struct nvmet_ctrl *ctrl = req->sq->ctrl;
 727	struct nvme_error_slot *new_error_slot;
 728	unsigned long flags;
 729
 730	req->cqe->status = cpu_to_le16(status << 1);
 731
 732	if (!ctrl || req->error_loc == NVMET_NO_ERROR_LOC)
 733		return;
 734
 735	spin_lock_irqsave(&ctrl->error_lock, flags);
 736	ctrl->err_counter++;
 737	new_error_slot =
 738		&ctrl->slots[ctrl->err_counter % NVMET_ERROR_LOG_SLOTS];
 739
 740	new_error_slot->error_count = cpu_to_le64(ctrl->err_counter);
 741	new_error_slot->sqid = cpu_to_le16(req->sq->qid);
 742	new_error_slot->cmdid = cpu_to_le16(req->cmd->common.command_id);
 743	new_error_slot->status_field = cpu_to_le16(status << 1);
 744	new_error_slot->param_error_location = cpu_to_le16(req->error_loc);
 745	new_error_slot->lba = cpu_to_le64(req->error_slba);
 746	new_error_slot->nsid = req->cmd->common.nsid;
 747	spin_unlock_irqrestore(&ctrl->error_lock, flags);
 748
 749	/* set the more bit for this request */
 750	req->cqe->status |= cpu_to_le16(1 << 14);
 751}
 752
 753static void __nvmet_req_complete(struct nvmet_req *req, u16 status)
 754{
 755	struct nvmet_ns *ns = req->ns;
 756
 757	if (!req->sq->sqhd_disabled)
 758		nvmet_update_sq_head(req);
 759	req->cqe->sq_id = cpu_to_le16(req->sq->qid);
 760	req->cqe->command_id = req->cmd->common.command_id;
 761
 762	if (unlikely(status))
 763		nvmet_set_error(req, status);
 764
 765	trace_nvmet_req_complete(req);
 766
 767	req->ops->queue_response(req);
 768	if (ns)
 769		nvmet_put_namespace(ns);
 770}
 771
 772void nvmet_req_complete(struct nvmet_req *req, u16 status)
 773{
 774	struct nvmet_sq *sq = req->sq;
 775
 776	__nvmet_req_complete(req, status);
 777	percpu_ref_put(&sq->ref);
 778}
 779EXPORT_SYMBOL_GPL(nvmet_req_complete);
 780
 781void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq,
 782		u16 qid, u16 size)
 783{
 784	cq->qid = qid;
 785	cq->size = size;
 786}
 787
 788void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq,
 789		u16 qid, u16 size)
 790{
 791	sq->sqhd = 0;
 792	sq->qid = qid;
 793	sq->size = size;
 794
 795	ctrl->sqs[qid] = sq;
 796}
 797
 798static void nvmet_confirm_sq(struct percpu_ref *ref)
 799{
 800	struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref);
 801
 802	complete(&sq->confirm_done);
 803}
 804
 805void nvmet_sq_destroy(struct nvmet_sq *sq)
 806{
 807	struct nvmet_ctrl *ctrl = sq->ctrl;
 808
 809	/*
 810	 * If this is the admin queue, complete all AERs so that our
 811	 * queue doesn't have outstanding requests on it.
 812	 */
 813	if (ctrl && ctrl->sqs && ctrl->sqs[0] == sq)
 814		nvmet_async_events_failall(ctrl);
 815	percpu_ref_kill_and_confirm(&sq->ref, nvmet_confirm_sq);
 816	wait_for_completion(&sq->confirm_done);
 817	wait_for_completion(&sq->free_done);
 818	percpu_ref_exit(&sq->ref);
 819	nvmet_auth_sq_free(sq);
 820
 821	if (ctrl) {
 822		/*
 823		 * The teardown flow may take some time, and the host may not
 824		 * send us keep-alive during this period, hence reset the
 825		 * traffic based keep-alive timer so we don't trigger a
 826		 * controller teardown as a result of a keep-alive expiration.
 827		 */
 828		ctrl->reset_tbkas = true;
 829		sq->ctrl->sqs[sq->qid] = NULL;
 830		nvmet_ctrl_put(ctrl);
 831		sq->ctrl = NULL; /* allows reusing the queue later */
 832	}
 833}
 834EXPORT_SYMBOL_GPL(nvmet_sq_destroy);
 835
 836static void nvmet_sq_free(struct percpu_ref *ref)
 837{
 838	struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref);
 839
 840	complete(&sq->free_done);
 841}
 842
 843int nvmet_sq_init(struct nvmet_sq *sq)
 844{
 845	int ret;
 846
 847	ret = percpu_ref_init(&sq->ref, nvmet_sq_free, 0, GFP_KERNEL);
 848	if (ret) {
 849		pr_err("percpu_ref init failed!\n");
 850		return ret;
 851	}
 852	init_completion(&sq->free_done);
 853	init_completion(&sq->confirm_done);
 854	nvmet_auth_sq_init(sq);
 855
 856	return 0;
 857}
 858EXPORT_SYMBOL_GPL(nvmet_sq_init);
 859
 860static inline u16 nvmet_check_ana_state(struct nvmet_port *port,
 861		struct nvmet_ns *ns)
 862{
 863	enum nvme_ana_state state = port->ana_state[ns->anagrpid];
 864
 865	if (unlikely(state == NVME_ANA_INACCESSIBLE))
 866		return NVME_SC_ANA_INACCESSIBLE;
 867	if (unlikely(state == NVME_ANA_PERSISTENT_LOSS))
 868		return NVME_SC_ANA_PERSISTENT_LOSS;
 869	if (unlikely(state == NVME_ANA_CHANGE))
 870		return NVME_SC_ANA_TRANSITION;
 871	return 0;
 872}
 873
 874static inline u16 nvmet_io_cmd_check_access(struct nvmet_req *req)
 875{
 876	if (unlikely(req->ns->readonly)) {
 877		switch (req->cmd->common.opcode) {
 878		case nvme_cmd_read:
 879		case nvme_cmd_flush:
 880			break;
 881		default:
 882			return NVME_SC_NS_WRITE_PROTECTED;
 883		}
 884	}
 885
 886	return 0;
 887}
 888
 889static u16 nvmet_parse_io_cmd(struct nvmet_req *req)
 890{
 891	struct nvme_command *cmd = req->cmd;
 892	u16 ret;
 893
 894	if (nvme_is_fabrics(cmd))
 895		return nvmet_parse_fabrics_io_cmd(req);
 896
 897	if (unlikely(!nvmet_check_auth_status(req)))
 898		return NVME_SC_AUTH_REQUIRED | NVME_SC_DNR;
 899
 900	ret = nvmet_check_ctrl_status(req);
 901	if (unlikely(ret))
 902		return ret;
 903
 904	if (nvmet_is_passthru_req(req))
 905		return nvmet_parse_passthru_io_cmd(req);
 906
 907	ret = nvmet_req_find_ns(req);
 908	if (unlikely(ret))
 909		return ret;
 910
 911	ret = nvmet_check_ana_state(req->port, req->ns);
 912	if (unlikely(ret)) {
 913		req->error_loc = offsetof(struct nvme_common_command, nsid);
 914		return ret;
 915	}
 916	ret = nvmet_io_cmd_check_access(req);
 917	if (unlikely(ret)) {
 918		req->error_loc = offsetof(struct nvme_common_command, nsid);
 919		return ret;
 920	}
 921
 922	switch (req->ns->csi) {
 923	case NVME_CSI_NVM:
 924		if (req->ns->file)
 925			return nvmet_file_parse_io_cmd(req);
 926		return nvmet_bdev_parse_io_cmd(req);
 927	case NVME_CSI_ZNS:
 928		if (IS_ENABLED(CONFIG_BLK_DEV_ZONED))
 929			return nvmet_bdev_zns_parse_io_cmd(req);
 930		return NVME_SC_INVALID_IO_CMD_SET;
 931	default:
 932		return NVME_SC_INVALID_IO_CMD_SET;
 933	}
 934}
 935
 936bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
 937		struct nvmet_sq *sq, const struct nvmet_fabrics_ops *ops)
 938{
 939	u8 flags = req->cmd->common.flags;
 940	u16 status;
 941
 942	req->cq = cq;
 943	req->sq = sq;
 944	req->ops = ops;
 945	req->sg = NULL;
 946	req->metadata_sg = NULL;
 947	req->sg_cnt = 0;
 948	req->metadata_sg_cnt = 0;
 949	req->transfer_len = 0;
 950	req->metadata_len = 0;
 951	req->cqe->status = 0;
 952	req->cqe->sq_head = 0;
 953	req->ns = NULL;
 954	req->error_loc = NVMET_NO_ERROR_LOC;
 955	req->error_slba = 0;
 956
 957	/* no support for fused commands yet */
 958	if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) {
 959		req->error_loc = offsetof(struct nvme_common_command, flags);
 960		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 961		goto fail;
 962	}
 963
 964	/*
 965	 * For fabrics, PSDT field shall describe metadata pointer (MPTR) that
 966	 * contains an address of a single contiguous physical buffer that is
 967	 * byte aligned.
 968	 */
 969	if (unlikely((flags & NVME_CMD_SGL_ALL) != NVME_CMD_SGL_METABUF)) {
 970		req->error_loc = offsetof(struct nvme_common_command, flags);
 971		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 972		goto fail;
 973	}
 974
 975	if (unlikely(!req->sq->ctrl))
 976		/* will return an error for any non-connect command: */
 977		status = nvmet_parse_connect_cmd(req);
 978	else if (likely(req->sq->qid != 0))
 979		status = nvmet_parse_io_cmd(req);
 980	else
 981		status = nvmet_parse_admin_cmd(req);
 982
 983	if (status)
 984		goto fail;
 985
 986	trace_nvmet_req_init(req, req->cmd);
 987
 988	if (unlikely(!percpu_ref_tryget_live(&sq->ref))) {
 989		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 990		goto fail;
 991	}
 992
 993	if (sq->ctrl)
 994		sq->ctrl->reset_tbkas = true;
 995
 996	return true;
 997
 998fail:
 999	__nvmet_req_complete(req, status);
1000	return false;
1001}
1002EXPORT_SYMBOL_GPL(nvmet_req_init);
1003
1004void nvmet_req_uninit(struct nvmet_req *req)
1005{
1006	percpu_ref_put(&req->sq->ref);
1007	if (req->ns)
1008		nvmet_put_namespace(req->ns);
1009}
1010EXPORT_SYMBOL_GPL(nvmet_req_uninit);
1011
1012bool nvmet_check_transfer_len(struct nvmet_req *req, size_t len)
1013{
1014	if (unlikely(len != req->transfer_len)) {
1015		req->error_loc = offsetof(struct nvme_common_command, dptr);
1016		nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR);
1017		return false;
1018	}
1019
1020	return true;
1021}
1022EXPORT_SYMBOL_GPL(nvmet_check_transfer_len);
1023
1024bool nvmet_check_data_len_lte(struct nvmet_req *req, size_t data_len)
1025{
1026	if (unlikely(data_len > req->transfer_len)) {
1027		req->error_loc = offsetof(struct nvme_common_command, dptr);
1028		nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR);
1029		return false;
1030	}
1031
1032	return true;
1033}
1034
1035static unsigned int nvmet_data_transfer_len(struct nvmet_req *req)
1036{
1037	return req->transfer_len - req->metadata_len;
1038}
1039
1040static int nvmet_req_alloc_p2pmem_sgls(struct pci_dev *p2p_dev,
1041		struct nvmet_req *req)
1042{
1043	req->sg = pci_p2pmem_alloc_sgl(p2p_dev, &req->sg_cnt,
1044			nvmet_data_transfer_len(req));
1045	if (!req->sg)
1046		goto out_err;
1047
1048	if (req->metadata_len) {
1049		req->metadata_sg = pci_p2pmem_alloc_sgl(p2p_dev,
1050				&req->metadata_sg_cnt, req->metadata_len);
1051		if (!req->metadata_sg)
1052			goto out_free_sg;
1053	}
1054
1055	req->p2p_dev = p2p_dev;
1056
1057	return 0;
1058out_free_sg:
1059	pci_p2pmem_free_sgl(req->p2p_dev, req->sg);
1060out_err:
1061	return -ENOMEM;
1062}
1063
1064static struct pci_dev *nvmet_req_find_p2p_dev(struct nvmet_req *req)
1065{
1066	if (!IS_ENABLED(CONFIG_PCI_P2PDMA) ||
1067	    !req->sq->ctrl || !req->sq->qid || !req->ns)
1068		return NULL;
1069	return radix_tree_lookup(&req->sq->ctrl->p2p_ns_map, req->ns->nsid);
1070}
1071
1072int nvmet_req_alloc_sgls(struct nvmet_req *req)
1073{
1074	struct pci_dev *p2p_dev = nvmet_req_find_p2p_dev(req);
1075
1076	if (p2p_dev && !nvmet_req_alloc_p2pmem_sgls(p2p_dev, req))
1077		return 0;
1078
1079	req->sg = sgl_alloc(nvmet_data_transfer_len(req), GFP_KERNEL,
1080			    &req->sg_cnt);
1081	if (unlikely(!req->sg))
1082		goto out;
1083
1084	if (req->metadata_len) {
1085		req->metadata_sg = sgl_alloc(req->metadata_len, GFP_KERNEL,
1086					     &req->metadata_sg_cnt);
1087		if (unlikely(!req->metadata_sg))
1088			goto out_free;
1089	}
1090
1091	return 0;
1092out_free:
1093	sgl_free(req->sg);
1094out:
1095	return -ENOMEM;
1096}
1097EXPORT_SYMBOL_GPL(nvmet_req_alloc_sgls);
1098
1099void nvmet_req_free_sgls(struct nvmet_req *req)
1100{
1101	if (req->p2p_dev) {
1102		pci_p2pmem_free_sgl(req->p2p_dev, req->sg);
1103		if (req->metadata_sg)
1104			pci_p2pmem_free_sgl(req->p2p_dev, req->metadata_sg);
1105		req->p2p_dev = NULL;
1106	} else {
1107		sgl_free(req->sg);
1108		if (req->metadata_sg)
1109			sgl_free(req->metadata_sg);
1110	}
1111
1112	req->sg = NULL;
1113	req->metadata_sg = NULL;
1114	req->sg_cnt = 0;
1115	req->metadata_sg_cnt = 0;
1116}
1117EXPORT_SYMBOL_GPL(nvmet_req_free_sgls);
1118
1119static inline bool nvmet_cc_en(u32 cc)
1120{
1121	return (cc >> NVME_CC_EN_SHIFT) & 0x1;
1122}
1123
1124static inline u8 nvmet_cc_css(u32 cc)
1125{
1126	return (cc >> NVME_CC_CSS_SHIFT) & 0x7;
1127}
1128
1129static inline u8 nvmet_cc_mps(u32 cc)
1130{
1131	return (cc >> NVME_CC_MPS_SHIFT) & 0xf;
1132}
1133
1134static inline u8 nvmet_cc_ams(u32 cc)
1135{
1136	return (cc >> NVME_CC_AMS_SHIFT) & 0x7;
1137}
1138
1139static inline u8 nvmet_cc_shn(u32 cc)
1140{
1141	return (cc >> NVME_CC_SHN_SHIFT) & 0x3;
1142}
1143
1144static inline u8 nvmet_cc_iosqes(u32 cc)
1145{
1146	return (cc >> NVME_CC_IOSQES_SHIFT) & 0xf;
1147}
1148
1149static inline u8 nvmet_cc_iocqes(u32 cc)
1150{
1151	return (cc >> NVME_CC_IOCQES_SHIFT) & 0xf;
1152}
1153
1154static inline bool nvmet_css_supported(u8 cc_css)
1155{
1156	switch (cc_css << NVME_CC_CSS_SHIFT) {
1157	case NVME_CC_CSS_NVM:
1158	case NVME_CC_CSS_CSI:
1159		return true;
1160	default:
1161		return false;
1162	}
1163}
1164
1165static void nvmet_start_ctrl(struct nvmet_ctrl *ctrl)
1166{
1167	lockdep_assert_held(&ctrl->lock);
1168
1169	/*
1170	 * Only I/O controllers should verify iosqes,iocqes.
1171	 * Strictly speaking, the spec says a discovery controller
1172	 * should verify iosqes,iocqes are zeroed, however that
1173	 * would break backwards compatibility, so don't enforce it.
1174	 */
1175	if (!nvmet_is_disc_subsys(ctrl->subsys) &&
1176	    (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES ||
1177	     nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES)) {
1178		ctrl->csts = NVME_CSTS_CFS;
1179		return;
1180	}
1181
1182	if (nvmet_cc_mps(ctrl->cc) != 0 ||
1183	    nvmet_cc_ams(ctrl->cc) != 0 ||
1184	    !nvmet_css_supported(nvmet_cc_css(ctrl->cc))) {
1185		ctrl->csts = NVME_CSTS_CFS;
1186		return;
1187	}
1188
1189	ctrl->csts = NVME_CSTS_RDY;
1190
1191	/*
1192	 * Controllers that are not yet enabled should not really enforce the
1193	 * keep alive timeout, but we still want to track a timeout and cleanup
1194	 * in case a host died before it enabled the controller.  Hence, simply
1195	 * reset the keep alive timer when the controller is enabled.
1196	 */
1197	if (ctrl->kato)
1198		mod_delayed_work(nvmet_wq, &ctrl->ka_work, ctrl->kato * HZ);
1199}
1200
1201static void nvmet_clear_ctrl(struct nvmet_ctrl *ctrl)
1202{
1203	lockdep_assert_held(&ctrl->lock);
1204
1205	/* XXX: tear down queues? */
1206	ctrl->csts &= ~NVME_CSTS_RDY;
1207	ctrl->cc = 0;
1208}
1209
1210void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new)
1211{
1212	u32 old;
1213
1214	mutex_lock(&ctrl->lock);
1215	old = ctrl->cc;
1216	ctrl->cc = new;
1217
1218	if (nvmet_cc_en(new) && !nvmet_cc_en(old))
1219		nvmet_start_ctrl(ctrl);
1220	if (!nvmet_cc_en(new) && nvmet_cc_en(old))
1221		nvmet_clear_ctrl(ctrl);
1222	if (nvmet_cc_shn(new) && !nvmet_cc_shn(old)) {
1223		nvmet_clear_ctrl(ctrl);
1224		ctrl->csts |= NVME_CSTS_SHST_CMPLT;
1225	}
1226	if (!nvmet_cc_shn(new) && nvmet_cc_shn(old))
1227		ctrl->csts &= ~NVME_CSTS_SHST_CMPLT;
1228	mutex_unlock(&ctrl->lock);
1229}
1230
1231static void nvmet_init_cap(struct nvmet_ctrl *ctrl)
1232{
1233	/* command sets supported: NVMe command set: */
1234	ctrl->cap = (1ULL << 37);
1235	/* Controller supports one or more I/O Command Sets */
1236	ctrl->cap |= (1ULL << 43);
1237	/* CC.EN timeout in 500msec units: */
1238	ctrl->cap |= (15ULL << 24);
1239	/* maximum queue entries supported: */
1240	if (ctrl->ops->get_max_queue_size)
1241		ctrl->cap |= min_t(u16, ctrl->ops->get_max_queue_size(ctrl),
1242				   ctrl->port->max_queue_size) - 1;
1243	else
1244		ctrl->cap |= ctrl->port->max_queue_size - 1;
1245
1246	if (nvmet_is_passthru_subsys(ctrl->subsys))
1247		nvmet_passthrough_override_cap(ctrl);
1248}
1249
1250struct nvmet_ctrl *nvmet_ctrl_find_get(const char *subsysnqn,
1251				       const char *hostnqn, u16 cntlid,
1252				       struct nvmet_req *req)
1253{
1254	struct nvmet_ctrl *ctrl = NULL;
1255	struct nvmet_subsys *subsys;
1256
1257	subsys = nvmet_find_get_subsys(req->port, subsysnqn);
1258	if (!subsys) {
1259		pr_warn("connect request for invalid subsystem %s!\n",
1260			subsysnqn);
1261		req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn);
1262		goto out;
1263	}
1264
1265	mutex_lock(&subsys->lock);
1266	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
1267		if (ctrl->cntlid == cntlid) {
1268			if (strncmp(hostnqn, ctrl->hostnqn, NVMF_NQN_SIZE)) {
1269				pr_warn("hostnqn mismatch.\n");
1270				continue;
1271			}
1272			if (!kref_get_unless_zero(&ctrl->ref))
1273				continue;
1274
1275			/* ctrl found */
1276			goto found;
1277		}
1278	}
1279
1280	ctrl = NULL; /* ctrl not found */
1281	pr_warn("could not find controller %d for subsys %s / host %s\n",
1282		cntlid, subsysnqn, hostnqn);
1283	req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(cntlid);
1284
1285found:
1286	mutex_unlock(&subsys->lock);
1287	nvmet_subsys_put(subsys);
1288out:
1289	return ctrl;
1290}
1291
1292u16 nvmet_check_ctrl_status(struct nvmet_req *req)
1293{
1294	if (unlikely(!(req->sq->ctrl->cc & NVME_CC_ENABLE))) {
1295		pr_err("got cmd %d while CC.EN == 0 on qid = %d\n",
1296		       req->cmd->common.opcode, req->sq->qid);
1297		return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
1298	}
1299
1300	if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
1301		pr_err("got cmd %d while CSTS.RDY == 0 on qid = %d\n",
1302		       req->cmd->common.opcode, req->sq->qid);
1303		return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
1304	}
1305
1306	if (unlikely(!nvmet_check_auth_status(req))) {
1307		pr_warn("qid %d not authenticated\n", req->sq->qid);
1308		return NVME_SC_AUTH_REQUIRED | NVME_SC_DNR;
1309	}
1310	return 0;
1311}
1312
1313bool nvmet_host_allowed(struct nvmet_subsys *subsys, const char *hostnqn)
1314{
1315	struct nvmet_host_link *p;
1316
1317	lockdep_assert_held(&nvmet_config_sem);
1318
1319	if (subsys->allow_any_host)
1320		return true;
1321
1322	if (nvmet_is_disc_subsys(subsys)) /* allow all access to disc subsys */
1323		return true;
1324
1325	list_for_each_entry(p, &subsys->hosts, entry) {
1326		if (!strcmp(nvmet_host_name(p->host), hostnqn))
1327			return true;
1328	}
1329
1330	return false;
1331}
1332
1333/*
1334 * Note: ctrl->subsys->lock should be held when calling this function
1335 */
1336static void nvmet_setup_p2p_ns_map(struct nvmet_ctrl *ctrl,
1337		struct nvmet_req *req)
1338{
1339	struct nvmet_ns *ns;
1340	unsigned long idx;
1341
1342	if (!req->p2p_client)
1343		return;
1344
1345	ctrl->p2p_client = get_device(req->p2p_client);
1346
1347	xa_for_each(&ctrl->subsys->namespaces, idx, ns)
1348		nvmet_p2pmem_ns_add_p2p(ctrl, ns);
1349}
1350
1351/*
1352 * Note: ctrl->subsys->lock should be held when calling this function
1353 */
1354static void nvmet_release_p2p_ns_map(struct nvmet_ctrl *ctrl)
1355{
1356	struct radix_tree_iter iter;
1357	void __rcu **slot;
1358
1359	radix_tree_for_each_slot(slot, &ctrl->p2p_ns_map, &iter, 0)
1360		pci_dev_put(radix_tree_deref_slot(slot));
1361
1362	put_device(ctrl->p2p_client);
1363}
1364
1365static void nvmet_fatal_error_handler(struct work_struct *work)
1366{
1367	struct nvmet_ctrl *ctrl =
1368			container_of(work, struct nvmet_ctrl, fatal_err_work);
1369
1370	pr_err("ctrl %d fatal error occurred!\n", ctrl->cntlid);
1371	ctrl->ops->delete_ctrl(ctrl);
1372}
1373
1374u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
1375		struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp)
1376{
1377	struct nvmet_subsys *subsys;
1378	struct nvmet_ctrl *ctrl;
1379	int ret;
1380	u16 status;
1381
1382	status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1383	subsys = nvmet_find_get_subsys(req->port, subsysnqn);
1384	if (!subsys) {
1385		pr_warn("connect request for invalid subsystem %s!\n",
1386			subsysnqn);
1387		req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn);
1388		req->error_loc = offsetof(struct nvme_common_command, dptr);
1389		goto out;
1390	}
1391
1392	down_read(&nvmet_config_sem);
1393	if (!nvmet_host_allowed(subsys, hostnqn)) {
1394		pr_info("connect by host %s for subsystem %s not allowed\n",
1395			hostnqn, subsysnqn);
1396		req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(hostnqn);
1397		up_read(&nvmet_config_sem);
1398		status = NVME_SC_CONNECT_INVALID_HOST | NVME_SC_DNR;
1399		req->error_loc = offsetof(struct nvme_common_command, dptr);
1400		goto out_put_subsystem;
1401	}
1402	up_read(&nvmet_config_sem);
1403
1404	status = NVME_SC_INTERNAL;
1405	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
1406	if (!ctrl)
1407		goto out_put_subsystem;
1408	mutex_init(&ctrl->lock);
1409
1410	ctrl->port = req->port;
1411	ctrl->ops = req->ops;
1412
1413#ifdef CONFIG_NVME_TARGET_PASSTHRU
1414	/* By default, set loop targets to clear IDS by default */
1415	if (ctrl->port->disc_addr.trtype == NVMF_TRTYPE_LOOP)
1416		subsys->clear_ids = 1;
1417#endif
1418
1419	INIT_WORK(&ctrl->async_event_work, nvmet_async_event_work);
1420	INIT_LIST_HEAD(&ctrl->async_events);
1421	INIT_RADIX_TREE(&ctrl->p2p_ns_map, GFP_KERNEL);
1422	INIT_WORK(&ctrl->fatal_err_work, nvmet_fatal_error_handler);
1423	INIT_DELAYED_WORK(&ctrl->ka_work, nvmet_keep_alive_timer);
1424
1425	memcpy(ctrl->subsysnqn, subsysnqn, NVMF_NQN_SIZE);
1426	memcpy(ctrl->hostnqn, hostnqn, NVMF_NQN_SIZE);
1427
1428	kref_init(&ctrl->ref);
1429	ctrl->subsys = subsys;
1430	ctrl->pi_support = ctrl->port->pi_enable && ctrl->subsys->pi_support;
1431	nvmet_init_cap(ctrl);
1432	WRITE_ONCE(ctrl->aen_enabled, NVMET_AEN_CFG_OPTIONAL);
1433
1434	ctrl->changed_ns_list = kmalloc_array(NVME_MAX_CHANGED_NAMESPACES,
1435			sizeof(__le32), GFP_KERNEL);
1436	if (!ctrl->changed_ns_list)
1437		goto out_free_ctrl;
1438
1439	ctrl->sqs = kcalloc(subsys->max_qid + 1,
1440			sizeof(struct nvmet_sq *),
1441			GFP_KERNEL);
1442	if (!ctrl->sqs)
1443		goto out_free_changed_ns_list;
1444
1445	ret = ida_alloc_range(&cntlid_ida,
1446			     subsys->cntlid_min, subsys->cntlid_max,
1447			     GFP_KERNEL);
1448	if (ret < 0) {
1449		status = NVME_SC_CONNECT_CTRL_BUSY | NVME_SC_DNR;
1450		goto out_free_sqs;
1451	}
1452	ctrl->cntlid = ret;
1453
1454	/*
1455	 * Discovery controllers may use some arbitrary high value
1456	 * in order to cleanup stale discovery sessions
1457	 */
1458	if (nvmet_is_disc_subsys(ctrl->subsys) && !kato)
1459		kato = NVMET_DISC_KATO_MS;
1460
1461	/* keep-alive timeout in seconds */
1462	ctrl->kato = DIV_ROUND_UP(kato, 1000);
1463
1464	ctrl->err_counter = 0;
1465	spin_lock_init(&ctrl->error_lock);
1466
1467	nvmet_start_keep_alive_timer(ctrl);
1468
1469	mutex_lock(&subsys->lock);
1470	list_add_tail(&ctrl->subsys_entry, &subsys->ctrls);
1471	nvmet_setup_p2p_ns_map(ctrl, req);
1472	mutex_unlock(&subsys->lock);
1473
1474	*ctrlp = ctrl;
1475	return 0;
1476
1477out_free_sqs:
1478	kfree(ctrl->sqs);
1479out_free_changed_ns_list:
1480	kfree(ctrl->changed_ns_list);
1481out_free_ctrl:
1482	kfree(ctrl);
1483out_put_subsystem:
1484	nvmet_subsys_put(subsys);
1485out:
1486	return status;
1487}
1488
1489static void nvmet_ctrl_free(struct kref *ref)
1490{
1491	struct nvmet_ctrl *ctrl = container_of(ref, struct nvmet_ctrl, ref);
1492	struct nvmet_subsys *subsys = ctrl->subsys;
1493
1494	mutex_lock(&subsys->lock);
1495	nvmet_release_p2p_ns_map(ctrl);
1496	list_del(&ctrl->subsys_entry);
1497	mutex_unlock(&subsys->lock);
1498
1499	nvmet_stop_keep_alive_timer(ctrl);
1500
1501	flush_work(&ctrl->async_event_work);
1502	cancel_work_sync(&ctrl->fatal_err_work);
1503
1504	nvmet_destroy_auth(ctrl);
1505
1506	ida_free(&cntlid_ida, ctrl->cntlid);
1507
1508	nvmet_async_events_free(ctrl);
1509	kfree(ctrl->sqs);
1510	kfree(ctrl->changed_ns_list);
1511	kfree(ctrl);
1512
1513	nvmet_subsys_put(subsys);
1514}
1515
1516void nvmet_ctrl_put(struct nvmet_ctrl *ctrl)
1517{
1518	kref_put(&ctrl->ref, nvmet_ctrl_free);
1519}
1520
1521void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl)
1522{
1523	mutex_lock(&ctrl->lock);
1524	if (!(ctrl->csts & NVME_CSTS_CFS)) {
1525		ctrl->csts |= NVME_CSTS_CFS;
1526		queue_work(nvmet_wq, &ctrl->fatal_err_work);
1527	}
1528	mutex_unlock(&ctrl->lock);
1529}
1530EXPORT_SYMBOL_GPL(nvmet_ctrl_fatal_error);
1531
1532static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
1533		const char *subsysnqn)
1534{
1535	struct nvmet_subsys_link *p;
1536
1537	if (!port)
1538		return NULL;
1539
1540	if (!strcmp(NVME_DISC_SUBSYS_NAME, subsysnqn)) {
1541		if (!kref_get_unless_zero(&nvmet_disc_subsys->ref))
1542			return NULL;
1543		return nvmet_disc_subsys;
1544	}
1545
1546	down_read(&nvmet_config_sem);
1547	if (!strncmp(nvmet_disc_subsys->subsysnqn, subsysnqn,
1548				NVMF_NQN_SIZE)) {
1549		if (kref_get_unless_zero(&nvmet_disc_subsys->ref)) {
1550			up_read(&nvmet_config_sem);
1551			return nvmet_disc_subsys;
1552		}
1553	}
1554	list_for_each_entry(p, &port->subsystems, entry) {
1555		if (!strncmp(p->subsys->subsysnqn, subsysnqn,
1556				NVMF_NQN_SIZE)) {
1557			if (!kref_get_unless_zero(&p->subsys->ref))
1558				break;
1559			up_read(&nvmet_config_sem);
1560			return p->subsys;
1561		}
1562	}
1563	up_read(&nvmet_config_sem);
1564	return NULL;
1565}
1566
1567struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
1568		enum nvme_subsys_type type)
1569{
1570	struct nvmet_subsys *subsys;
1571	char serial[NVMET_SN_MAX_SIZE / 2];
1572	int ret;
1573
1574	subsys = kzalloc(sizeof(*subsys), GFP_KERNEL);
1575	if (!subsys)
1576		return ERR_PTR(-ENOMEM);
1577
1578	subsys->ver = NVMET_DEFAULT_VS;
1579	/* generate a random serial number as our controllers are ephemeral: */
1580	get_random_bytes(&serial, sizeof(serial));
1581	bin2hex(subsys->serial, &serial, sizeof(serial));
1582
1583	subsys->model_number = kstrdup(NVMET_DEFAULT_CTRL_MODEL, GFP_KERNEL);
1584	if (!subsys->model_number) {
1585		ret = -ENOMEM;
1586		goto free_subsys;
1587	}
1588
1589	subsys->ieee_oui = 0;
1590
1591	subsys->firmware_rev = kstrndup(UTS_RELEASE, NVMET_FR_MAX_SIZE, GFP_KERNEL);
1592	if (!subsys->firmware_rev) {
1593		ret = -ENOMEM;
1594		goto free_mn;
1595	}
1596
1597	switch (type) {
1598	case NVME_NQN_NVME:
1599		subsys->max_qid = NVMET_NR_QUEUES;
1600		break;
1601	case NVME_NQN_DISC:
1602	case NVME_NQN_CURR:
1603		subsys->max_qid = 0;
1604		break;
1605	default:
1606		pr_err("%s: Unknown Subsystem type - %d\n", __func__, type);
1607		ret = -EINVAL;
1608		goto free_fr;
1609	}
1610	subsys->type = type;
1611	subsys->subsysnqn = kstrndup(subsysnqn, NVMF_NQN_SIZE,
1612			GFP_KERNEL);
1613	if (!subsys->subsysnqn) {
1614		ret = -ENOMEM;
1615		goto free_fr;
1616	}
1617	subsys->cntlid_min = NVME_CNTLID_MIN;
1618	subsys->cntlid_max = NVME_CNTLID_MAX;
1619	kref_init(&subsys->ref);
1620
1621	mutex_init(&subsys->lock);
1622	xa_init(&subsys->namespaces);
1623	INIT_LIST_HEAD(&subsys->ctrls);
1624	INIT_LIST_HEAD(&subsys->hosts);
1625
1626	return subsys;
1627
1628free_fr:
1629	kfree(subsys->firmware_rev);
1630free_mn:
1631	kfree(subsys->model_number);
1632free_subsys:
1633	kfree(subsys);
1634	return ERR_PTR(ret);
1635}
1636
1637static void nvmet_subsys_free(struct kref *ref)
1638{
1639	struct nvmet_subsys *subsys =
1640		container_of(ref, struct nvmet_subsys, ref);
1641
1642	WARN_ON_ONCE(!xa_empty(&subsys->namespaces));
1643
1644	xa_destroy(&subsys->namespaces);
1645	nvmet_passthru_subsys_free(subsys);
1646
1647	kfree(subsys->subsysnqn);
1648	kfree(subsys->model_number);
1649	kfree(subsys->firmware_rev);
1650	kfree(subsys);
1651}
1652
1653void nvmet_subsys_del_ctrls(struct nvmet_subsys *subsys)
1654{
1655	struct nvmet_ctrl *ctrl;
1656
1657	mutex_lock(&subsys->lock);
1658	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
1659		ctrl->ops->delete_ctrl(ctrl);
1660	mutex_unlock(&subsys->lock);
1661}
1662
1663void nvmet_subsys_put(struct nvmet_subsys *subsys)
1664{
1665	kref_put(&subsys->ref, nvmet_subsys_free);
1666}
1667
1668static int __init nvmet_init(void)
1669{
1670	int error = -ENOMEM;
1671
1672	nvmet_ana_group_enabled[NVMET_DEFAULT_ANA_GRPID] = 1;
1673
1674	nvmet_bvec_cache = kmem_cache_create("nvmet-bvec",
1675			NVMET_MAX_MPOOL_BVEC * sizeof(struct bio_vec), 0,
1676			SLAB_HWCACHE_ALIGN, NULL);
1677	if (!nvmet_bvec_cache)
1678		return -ENOMEM;
1679
1680	zbd_wq = alloc_workqueue("nvmet-zbd-wq", WQ_MEM_RECLAIM, 0);
1681	if (!zbd_wq)
1682		goto out_destroy_bvec_cache;
1683
1684	buffered_io_wq = alloc_workqueue("nvmet-buffered-io-wq",
1685			WQ_MEM_RECLAIM, 0);
1686	if (!buffered_io_wq)
1687		goto out_free_zbd_work_queue;
1688
1689	nvmet_wq = alloc_workqueue("nvmet-wq",
1690			WQ_MEM_RECLAIM | WQ_UNBOUND, 0);
1691	if (!nvmet_wq)
1692		goto out_free_buffered_work_queue;
1693
1694	error = nvmet_init_discovery();
1695	if (error)
1696		goto out_free_nvmet_work_queue;
1697
1698	error = nvmet_init_configfs();
1699	if (error)
1700		goto out_exit_discovery;
1701	return 0;
1702
1703out_exit_discovery:
1704	nvmet_exit_discovery();
1705out_free_nvmet_work_queue:
1706	destroy_workqueue(nvmet_wq);
1707out_free_buffered_work_queue:
1708	destroy_workqueue(buffered_io_wq);
1709out_free_zbd_work_queue:
1710	destroy_workqueue(zbd_wq);
1711out_destroy_bvec_cache:
1712	kmem_cache_destroy(nvmet_bvec_cache);
1713	return error;
1714}
1715
1716static void __exit nvmet_exit(void)
1717{
1718	nvmet_exit_configfs();
1719	nvmet_exit_discovery();
1720	ida_destroy(&cntlid_ida);
1721	destroy_workqueue(nvmet_wq);
1722	destroy_workqueue(buffered_io_wq);
1723	destroy_workqueue(zbd_wq);
1724	kmem_cache_destroy(nvmet_bvec_cache);
1725
1726	BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_entry) != 1024);
1727	BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_hdr) != 1024);
1728}
1729
1730module_init(nvmet_init);
1731module_exit(nvmet_exit);
1732
1733MODULE_DESCRIPTION("NVMe target core framework");
1734MODULE_LICENSE("GPL v2");