1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Common code for the NVMe target.
4 * Copyright (c) 2015-2016 HGST, a Western Digital Company.
5 */
6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7#include <linux/module.h>
8#include <linux/random.h>
9#include <linux/rculist.h>
10#include <linux/pci-p2pdma.h>
11#include <linux/scatterlist.h>
12
13#define CREATE_TRACE_POINTS
14#include "trace.h"
15
16#include "nvmet.h"
17
18struct workqueue_struct *buffered_io_wq;
19static const struct nvmet_fabrics_ops *nvmet_transports[NVMF_TRTYPE_MAX];
20static DEFINE_IDA(cntlid_ida);
21
22/*
23 * This read/write semaphore is used to synchronize access to configuration
24 * information on a target system that will result in discovery log page
25 * information change for at least one host.
26 * The full list of resources to protected by this semaphore is:
27 *
28 *  - subsystems list
29 *  - per-subsystem allowed hosts list
30 *  - allow_any_host subsystem attribute
31 *  - nvmet_genctr
32 *  - the nvmet_transports array
33 *
34 * When updating any of those lists/structures write lock should be obtained,
35 * while when reading (popolating discovery log page or checking host-subsystem
36 * link) read lock is obtained to allow concurrent reads.
37 */
38DECLARE_RWSEM(nvmet_config_sem);
39
40u32 nvmet_ana_group_enabled[NVMET_MAX_ANAGRPS + 1];
41u64 nvmet_ana_chgcnt;
42DECLARE_RWSEM(nvmet_ana_sem);
43
44inline u16 errno_to_nvme_status(struct nvmet_req *req, int errno)
45{
46	u16 status;
47
48	switch (errno) {
49	case 0:
50		status = NVME_SC_SUCCESS;
51		break;
52	case -ENOSPC:
53		req->error_loc = offsetof(struct nvme_rw_command, length);
54		status = NVME_SC_CAP_EXCEEDED | NVME_SC_DNR;
55		break;
56	case -EREMOTEIO:
57		req->error_loc = offsetof(struct nvme_rw_command, slba);
58		status = NVME_SC_LBA_RANGE | NVME_SC_DNR;
59		break;
60	case -EOPNOTSUPP:
61		req->error_loc = offsetof(struct nvme_common_command, opcode);
62		switch (req->cmd->common.opcode) {
63		case nvme_cmd_dsm:
64		case nvme_cmd_write_zeroes:
65			status = NVME_SC_ONCS_NOT_SUPPORTED | NVME_SC_DNR;
66			break;
67		default:
68			status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
69		}
70		break;
71	case -ENODATA:
72		req->error_loc = offsetof(struct nvme_rw_command, nsid);
73		status = NVME_SC_ACCESS_DENIED;
74		break;
75	case -EIO:
76		fallthrough;
77	default:
78		req->error_loc = offsetof(struct nvme_common_command, opcode);
79		status = NVME_SC_INTERNAL | NVME_SC_DNR;
80	}
81
82	return status;
83}
84
85static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
86		const char *subsysnqn);
87
88u16 nvmet_copy_to_sgl(struct nvmet_req *req, off_t off, const void *buf,
89		size_t len)
90{
91	if (sg_pcopy_from_buffer(req->sg, req->sg_cnt, buf, len, off) != len) {
92		req->error_loc = offsetof(struct nvme_common_command, dptr);
93		return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
94	}
95	return 0;
96}
97
98u16 nvmet_copy_from_sgl(struct nvmet_req *req, off_t off, void *buf, size_t len)
99{
100	if (sg_pcopy_to_buffer(req->sg, req->sg_cnt, buf, len, off) != len) {
101		req->error_loc = offsetof(struct nvme_common_command, dptr);
102		return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
103	}
104	return 0;
105}
106
107u16 nvmet_zero_sgl(struct nvmet_req *req, off_t off, size_t len)
108{
109	if (sg_zero_buffer(req->sg, req->sg_cnt, len, off) != len) {
110		req->error_loc = offsetof(struct nvme_common_command, dptr);
111		return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
112	}
113	return 0;
114}
115
116static unsigned int nvmet_max_nsid(struct nvmet_subsys *subsys)
117{
118	unsigned long nsid = 0;
119	struct nvmet_ns *cur;
120	unsigned long idx;
121
122	xa_for_each(&subsys->namespaces, idx, cur)
123		nsid = cur->nsid;
124
125	return nsid;
126}
127
128static u32 nvmet_async_event_result(struct nvmet_async_event *aen)
129{
130	return aen->event_type | (aen->event_info << 8) | (aen->log_page << 16);
131}
132
133static void nvmet_async_events_failall(struct nvmet_ctrl *ctrl)
134{
135	u16 status = NVME_SC_INTERNAL | NVME_SC_DNR;
136	struct nvmet_req *req;
137
138	mutex_lock(&ctrl->lock);
139	while (ctrl->nr_async_event_cmds) {
140		req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds];
141		mutex_unlock(&ctrl->lock);
142		nvmet_req_complete(req, status);
143		mutex_lock(&ctrl->lock);
144	}
145	mutex_unlock(&ctrl->lock);
146}
147
148static void nvmet_async_events_process(struct nvmet_ctrl *ctrl)
149{
150	struct nvmet_async_event *aen;
151	struct nvmet_req *req;
152
153	mutex_lock(&ctrl->lock);
154	while (ctrl->nr_async_event_cmds && !list_empty(&ctrl->async_events)) {
155		aen = list_first_entry(&ctrl->async_events,
156				       struct nvmet_async_event, entry);
157		req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds];
158		nvmet_set_result(req, nvmet_async_event_result(aen));
159
160		list_del(&aen->entry);
161		kfree(aen);
162
163		mutex_unlock(&ctrl->lock);
164		trace_nvmet_async_event(ctrl, req->cqe->result.u32);
165		nvmet_req_complete(req, 0);
166		mutex_lock(&ctrl->lock);
167	}
168	mutex_unlock(&ctrl->lock);
169}
170
171static void nvmet_async_events_free(struct nvmet_ctrl *ctrl)
172{
173	struct nvmet_async_event *aen, *tmp;
174
175	mutex_lock(&ctrl->lock);
176	list_for_each_entry_safe(aen, tmp, &ctrl->async_events, entry) {
177		list_del(&aen->entry);
178		kfree(aen);
179	}
180	mutex_unlock(&ctrl->lock);
181}
182
183static void nvmet_async_event_work(struct work_struct *work)
184{
185	struct nvmet_ctrl *ctrl =
186		container_of(work, struct nvmet_ctrl, async_event_work);
187
188	nvmet_async_events_process(ctrl);
189}
190
191void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type,
192		u8 event_info, u8 log_page)
193{
194	struct nvmet_async_event *aen;
195
196	aen = kmalloc(sizeof(*aen), GFP_KERNEL);
197	if (!aen)
198		return;
199
200	aen->event_type = event_type;
201	aen->event_info = event_info;
202	aen->log_page = log_page;
203
204	mutex_lock(&ctrl->lock);
205	list_add_tail(&aen->entry, &ctrl->async_events);
206	mutex_unlock(&ctrl->lock);
207
208	schedule_work(&ctrl->async_event_work);
209}
210
211static void nvmet_add_to_changed_ns_log(struct nvmet_ctrl *ctrl, __le32 nsid)
212{
213	u32 i;
214
215	mutex_lock(&ctrl->lock);
216	if (ctrl->nr_changed_ns > NVME_MAX_CHANGED_NAMESPACES)
217		goto out_unlock;
218
219	for (i = 0; i < ctrl->nr_changed_ns; i++) {
220		if (ctrl->changed_ns_list[i] == nsid)
221			goto out_unlock;
222	}
223
224	if (ctrl->nr_changed_ns == NVME_MAX_CHANGED_NAMESPACES) {
225		ctrl->changed_ns_list[0] = cpu_to_le32(0xffffffff);
226		ctrl->nr_changed_ns = U32_MAX;
227		goto out_unlock;
228	}
229
230	ctrl->changed_ns_list[ctrl->nr_changed_ns++] = nsid;
231out_unlock:
232	mutex_unlock(&ctrl->lock);
233}
234
235void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid)
236{
237	struct nvmet_ctrl *ctrl;
238
239	lockdep_assert_held(&subsys->lock);
240
241	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
242		nvmet_add_to_changed_ns_log(ctrl, cpu_to_le32(nsid));
243		if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_NS_ATTR))
244			continue;
245		nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE,
246				NVME_AER_NOTICE_NS_CHANGED,
247				NVME_LOG_CHANGED_NS);
248	}
249}
250
251void nvmet_send_ana_event(struct nvmet_subsys *subsys,
252		struct nvmet_port *port)
253{
254	struct nvmet_ctrl *ctrl;
255
256	mutex_lock(&subsys->lock);
257	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
258		if (port && ctrl->port != port)
259			continue;
260		if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_ANA_CHANGE))
261			continue;
262		nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE,
263				NVME_AER_NOTICE_ANA, NVME_LOG_ANA);
264	}
265	mutex_unlock(&subsys->lock);
266}
267
268void nvmet_port_send_ana_event(struct nvmet_port *port)
269{
270	struct nvmet_subsys_link *p;
271
272	down_read(&nvmet_config_sem);
273	list_for_each_entry(p, &port->subsystems, entry)
274		nvmet_send_ana_event(p->subsys, port);
275	up_read(&nvmet_config_sem);
276}
277
278int nvmet_register_transport(const struct nvmet_fabrics_ops *ops)
279{
280	int ret = 0;
281
282	down_write(&nvmet_config_sem);
283	if (nvmet_transports[ops->type])
284		ret = -EINVAL;
285	else
286		nvmet_transports[ops->type] = ops;
287	up_write(&nvmet_config_sem);
288
289	return ret;
290}
291EXPORT_SYMBOL_GPL(nvmet_register_transport);
292
293void nvmet_unregister_transport(const struct nvmet_fabrics_ops *ops)
294{
295	down_write(&nvmet_config_sem);
296	nvmet_transports[ops->type] = NULL;
297	up_write(&nvmet_config_sem);
298}
299EXPORT_SYMBOL_GPL(nvmet_unregister_transport);
300
301void nvmet_port_del_ctrls(struct nvmet_port *port, struct nvmet_subsys *subsys)
302{
303	struct nvmet_ctrl *ctrl;
304
305	mutex_lock(&subsys->lock);
306	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
307		if (ctrl->port == port)
308			ctrl->ops->delete_ctrl(ctrl);
309	}
310	mutex_unlock(&subsys->lock);
311}
312
313int nvmet_enable_port(struct nvmet_port *port)
314{
315	const struct nvmet_fabrics_ops *ops;
316	int ret;
317
318	lockdep_assert_held(&nvmet_config_sem);
319
320	ops = nvmet_transports[port->disc_addr.trtype];
321	if (!ops) {
322		up_write(&nvmet_config_sem);
323		request_module("nvmet-transport-%d", port->disc_addr.trtype);
324		down_write(&nvmet_config_sem);
325		ops = nvmet_transports[port->disc_addr.trtype];
326		if (!ops) {
327			pr_err("transport type %d not supported\n",
328				port->disc_addr.trtype);
329			return -EINVAL;
330		}
331	}
332
333	if (!try_module_get(ops->owner))
334		return -EINVAL;
335
336	/*
337	 * If the user requested PI support and the transport isn't pi capable,
338	 * don't enable the port.
339	 */
340	if (port->pi_enable && !(ops->flags & NVMF_METADATA_SUPPORTED)) {
341		pr_err("T10-PI is not supported by transport type %d\n",
342		       port->disc_addr.trtype);
343		ret = -EINVAL;
344		goto out_put;
345	}
346
347	ret = ops->add_port(port);
348	if (ret)
349		goto out_put;
350
351	/* If the transport didn't set inline_data_size, then disable it. */
352	if (port->inline_data_size < 0)
353		port->inline_data_size = 0;
354
355	port->enabled = true;
356	port->tr_ops = ops;
357	return 0;
358
359out_put:
360	module_put(ops->owner);
361	return ret;
362}
363
364void nvmet_disable_port(struct nvmet_port *port)
365{
366	const struct nvmet_fabrics_ops *ops;
367
368	lockdep_assert_held(&nvmet_config_sem);
369
370	port->enabled = false;
371	port->tr_ops = NULL;
372
373	ops = nvmet_transports[port->disc_addr.trtype];
374	ops->remove_port(port);
375	module_put(ops->owner);
376}
377
378static void nvmet_keep_alive_timer(struct work_struct *work)
379{
380	struct nvmet_ctrl *ctrl = container_of(to_delayed_work(work),
381			struct nvmet_ctrl, ka_work);
382	bool reset_tbkas = ctrl->reset_tbkas;
383
384	ctrl->reset_tbkas = false;
385	if (reset_tbkas) {
386		pr_debug("ctrl %d reschedule traffic based keep-alive timer\n",
387			ctrl->cntlid);
388		schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
389		return;
390	}
391
392	pr_err("ctrl %d keep-alive timer (%d seconds) expired!\n",
393		ctrl->cntlid, ctrl->kato);
394
395	nvmet_ctrl_fatal_error(ctrl);
396}
397
398void nvmet_start_keep_alive_timer(struct nvmet_ctrl *ctrl)
399{
400	if (unlikely(ctrl->kato == 0))
401		return;
402
403	pr_debug("ctrl %d start keep-alive timer for %d secs\n",
404		ctrl->cntlid, ctrl->kato);
405
406	INIT_DELAYED_WORK(&ctrl->ka_work, nvmet_keep_alive_timer);
407	schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
408}
409
410void nvmet_stop_keep_alive_timer(struct nvmet_ctrl *ctrl)
411{
412	if (unlikely(ctrl->kato == 0))
413		return;
414
415	pr_debug("ctrl %d stop keep-alive\n", ctrl->cntlid);
416
417	cancel_delayed_work_sync(&ctrl->ka_work);
418}
419
420struct nvmet_ns *nvmet_find_namespace(struct nvmet_ctrl *ctrl, __le32 nsid)
421{
422	struct nvmet_ns *ns;
423
424	ns = xa_load(&ctrl->subsys->namespaces, le32_to_cpu(nsid));
425	if (ns)
426		percpu_ref_get(&ns->ref);
427
428	return ns;
429}
430
431static void nvmet_destroy_namespace(struct percpu_ref *ref)
432{
433	struct nvmet_ns *ns = container_of(ref, struct nvmet_ns, ref);
434
435	complete(&ns->disable_done);
436}
437
438void nvmet_put_namespace(struct nvmet_ns *ns)
439{
440	percpu_ref_put(&ns->ref);
441}
442
443static void nvmet_ns_dev_disable(struct nvmet_ns *ns)
444{
445	nvmet_bdev_ns_disable(ns);
446	nvmet_file_ns_disable(ns);
447}
448
449static int nvmet_p2pmem_ns_enable(struct nvmet_ns *ns)
450{
451	int ret;
452	struct pci_dev *p2p_dev;
453
454	if (!ns->use_p2pmem)
455		return 0;
456
457	if (!ns->bdev) {
458		pr_err("peer-to-peer DMA is not supported by non-block device namespaces\n");
459		return -EINVAL;
460	}
461
462	if (!blk_queue_pci_p2pdma(ns->bdev->bd_disk->queue)) {
463		pr_err("peer-to-peer DMA is not supported by the driver of %s\n",
464		       ns->device_path);
465		return -EINVAL;
466	}
467
468	if (ns->p2p_dev) {
469		ret = pci_p2pdma_distance(ns->p2p_dev, nvmet_ns_dev(ns), true);
470		if (ret < 0)
471			return -EINVAL;
472	} else {
473		/*
474		 * Right now we just check that there is p2pmem available so
475		 * we can report an error to the user right away if there
476		 * is not. We'll find the actual device to use once we
477		 * setup the controller when the port's device is available.
478		 */
479
480		p2p_dev = pci_p2pmem_find(nvmet_ns_dev(ns));
481		if (!p2p_dev) {
482			pr_err("no peer-to-peer memory is available for %s\n",
483			       ns->device_path);
484			return -EINVAL;
485		}
486
487		pci_dev_put(p2p_dev);
488	}
489
490	return 0;
491}
492
493/*
494 * Note: ctrl->subsys->lock should be held when calling this function
495 */
496static void nvmet_p2pmem_ns_add_p2p(struct nvmet_ctrl *ctrl,
497				    struct nvmet_ns *ns)
498{
499	struct device *clients[2];
500	struct pci_dev *p2p_dev;
501	int ret;
502
503	if (!ctrl->p2p_client || !ns->use_p2pmem)
504		return;
505
506	if (ns->p2p_dev) {
507		ret = pci_p2pdma_distance(ns->p2p_dev, ctrl->p2p_client, true);
508		if (ret < 0)
509			return;
510
511		p2p_dev = pci_dev_get(ns->p2p_dev);
512	} else {
513		clients[0] = ctrl->p2p_client;
514		clients[1] = nvmet_ns_dev(ns);
515
516		p2p_dev = pci_p2pmem_find_many(clients, ARRAY_SIZE(clients));
517		if (!p2p_dev) {
518			pr_err("no peer-to-peer memory is available that's supported by %s and %s\n",
519			       dev_name(ctrl->p2p_client), ns->device_path);
520			return;
521		}
522	}
523
524	ret = radix_tree_insert(&ctrl->p2p_ns_map, ns->nsid, p2p_dev);
525	if (ret < 0)
526		pci_dev_put(p2p_dev);
527
528	pr_info("using p2pmem on %s for nsid %d\n", pci_name(p2p_dev),
529		ns->nsid);
530}
531
532void nvmet_ns_revalidate(struct nvmet_ns *ns)
533{
534	loff_t oldsize = ns->size;
535
536	if (ns->bdev)
537		nvmet_bdev_ns_revalidate(ns);
538	else
539		nvmet_file_ns_revalidate(ns);
540
541	if (oldsize != ns->size)
542		nvmet_ns_changed(ns->subsys, ns->nsid);
543}
544
545int nvmet_ns_enable(struct nvmet_ns *ns)
546{
547	struct nvmet_subsys *subsys = ns->subsys;
548	struct nvmet_ctrl *ctrl;
549	int ret;
550
551	mutex_lock(&subsys->lock);
552	ret = 0;
553
554	if (nvmet_passthru_ctrl(subsys)) {
555		pr_info("cannot enable both passthru and regular namespaces for a single subsystem");
556		goto out_unlock;
557	}
558
559	if (ns->enabled)
560		goto out_unlock;
561
562	ret = -EMFILE;
563	if (subsys->nr_namespaces == NVMET_MAX_NAMESPACES)
564		goto out_unlock;
565
566	ret = nvmet_bdev_ns_enable(ns);
567	if (ret == -ENOTBLK)
568		ret = nvmet_file_ns_enable(ns);
569	if (ret)
570		goto out_unlock;
571
572	ret = nvmet_p2pmem_ns_enable(ns);
573	if (ret)
574		goto out_dev_disable;
575
576	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
577		nvmet_p2pmem_ns_add_p2p(ctrl, ns);
578
579	ret = percpu_ref_init(&ns->ref, nvmet_destroy_namespace,
580				0, GFP_KERNEL);
581	if (ret)
582		goto out_dev_put;
583
584	if (ns->nsid > subsys->max_nsid)
585		subsys->max_nsid = ns->nsid;
586
587	ret = xa_insert(&subsys->namespaces, ns->nsid, ns, GFP_KERNEL);
588	if (ret)
589		goto out_restore_subsys_maxnsid;
590
591	subsys->nr_namespaces++;
592
593	nvmet_ns_changed(subsys, ns->nsid);
594	ns->enabled = true;
595	ret = 0;
596out_unlock:
597	mutex_unlock(&subsys->lock);
598	return ret;
599
600out_restore_subsys_maxnsid:
601	subsys->max_nsid = nvmet_max_nsid(subsys);
602	percpu_ref_exit(&ns->ref);
603out_dev_put:
604	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
605		pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
606out_dev_disable:
607	nvmet_ns_dev_disable(ns);
608	goto out_unlock;
609}
610
611void nvmet_ns_disable(struct nvmet_ns *ns)
612{
613	struct nvmet_subsys *subsys = ns->subsys;
614	struct nvmet_ctrl *ctrl;
615
616	mutex_lock(&subsys->lock);
617	if (!ns->enabled)
618		goto out_unlock;
619
620	ns->enabled = false;
621	xa_erase(&ns->subsys->namespaces, ns->nsid);
622	if (ns->nsid == subsys->max_nsid)
623		subsys->max_nsid = nvmet_max_nsid(subsys);
624
625	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
626		pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid));
627
628	mutex_unlock(&subsys->lock);
629
630	/*
631	 * Now that we removed the namespaces from the lookup list, we
632	 * can kill the per_cpu ref and wait for any remaining references
633	 * to be dropped, as well as a RCU grace period for anyone only
634	 * using the namepace under rcu_read_lock().  Note that we can't
635	 * use call_rcu here as we need to ensure the namespaces have
636	 * been fully destroyed before unloading the module.
637	 */
638	percpu_ref_kill(&ns->ref);
639	synchronize_rcu();
640	wait_for_completion(&ns->disable_done);
641	percpu_ref_exit(&ns->ref);
642
643	mutex_lock(&subsys->lock);
644
645	subsys->nr_namespaces--;
646	nvmet_ns_changed(subsys, ns->nsid);
647	nvmet_ns_dev_disable(ns);
648out_unlock:
649	mutex_unlock(&subsys->lock);
650}
651
652void nvmet_ns_free(struct nvmet_ns *ns)
653{
654	nvmet_ns_disable(ns);
655
656	down_write(&nvmet_ana_sem);
657	nvmet_ana_group_enabled[ns->anagrpid]--;
658	up_write(&nvmet_ana_sem);
659
660	kfree(ns->device_path);
661	kfree(ns);
662}
663
664struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid)
665{
666	struct nvmet_ns *ns;
667
668	ns = kzalloc(sizeof(*ns), GFP_KERNEL);
669	if (!ns)
670		return NULL;
671
672	init_completion(&ns->disable_done);
673
674	ns->nsid = nsid;
675	ns->subsys = subsys;
676
677	down_write(&nvmet_ana_sem);
678	ns->anagrpid = NVMET_DEFAULT_ANA_GRPID;
679	nvmet_ana_group_enabled[ns->anagrpid]++;
680	up_write(&nvmet_ana_sem);
681
682	uuid_gen(&ns->uuid);
683	ns->buffered_io = false;
684
685	return ns;
686}
687
688static void nvmet_update_sq_head(struct nvmet_req *req)
689{
690	if (req->sq->size) {
691		u32 old_sqhd, new_sqhd;
692
693		do {
694			old_sqhd = req->sq->sqhd;
695			new_sqhd = (old_sqhd + 1) % req->sq->size;
696		} while (cmpxchg(&req->sq->sqhd, old_sqhd, new_sqhd) !=
697					old_sqhd);
698	}
699	req->cqe->sq_head = cpu_to_le16(req->sq->sqhd & 0x0000FFFF);
700}
701
702static void nvmet_set_error(struct nvmet_req *req, u16 status)
703{
704	struct nvmet_ctrl *ctrl = req->sq->ctrl;
705	struct nvme_error_slot *new_error_slot;
706	unsigned long flags;
707
708	req->cqe->status = cpu_to_le16(status << 1);
709
710	if (!ctrl || req->error_loc == NVMET_NO_ERROR_LOC)
711		return;
712
713	spin_lock_irqsave(&ctrl->error_lock, flags);
714	ctrl->err_counter++;
715	new_error_slot =
716		&ctrl->slots[ctrl->err_counter % NVMET_ERROR_LOG_SLOTS];
717
718	new_error_slot->error_count = cpu_to_le64(ctrl->err_counter);
719	new_error_slot->sqid = cpu_to_le16(req->sq->qid);
720	new_error_slot->cmdid = cpu_to_le16(req->cmd->common.command_id);
721	new_error_slot->status_field = cpu_to_le16(status << 1);
722	new_error_slot->param_error_location = cpu_to_le16(req->error_loc);
723	new_error_slot->lba = cpu_to_le64(req->error_slba);
724	new_error_slot->nsid = req->cmd->common.nsid;
725	spin_unlock_irqrestore(&ctrl->error_lock, flags);
726
727	/* set the more bit for this request */
728	req->cqe->status |= cpu_to_le16(1 << 14);
729}
730
731static void __nvmet_req_complete(struct nvmet_req *req, u16 status)
732{
733	struct nvmet_ns *ns = req->ns;
734
735	if (!req->sq->sqhd_disabled)
736		nvmet_update_sq_head(req);
737	req->cqe->sq_id = cpu_to_le16(req->sq->qid);
738	req->cqe->command_id = req->cmd->common.command_id;
739
740	if (unlikely(status))
741		nvmet_set_error(req, status);
742
743	trace_nvmet_req_complete(req);
744
745	req->ops->queue_response(req);
746	if (ns)
747		nvmet_put_namespace(ns);
748}
749
750void nvmet_req_complete(struct nvmet_req *req, u16 status)
751{
752	struct nvmet_sq *sq = req->sq;
753
754	__nvmet_req_complete(req, status);
755	percpu_ref_put(&sq->ref);
756}
757EXPORT_SYMBOL_GPL(nvmet_req_complete);
758
759void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq,
760		u16 qid, u16 size)
761{
762	cq->qid = qid;
763	cq->size = size;
764}
765
766void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq,
767		u16 qid, u16 size)
768{
769	sq->sqhd = 0;
770	sq->qid = qid;
771	sq->size = size;
772
773	ctrl->sqs[qid] = sq;
774}
775
776static void nvmet_confirm_sq(struct percpu_ref *ref)
777{
778	struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref);
779
780	complete(&sq->confirm_done);
781}
782
783void nvmet_sq_destroy(struct nvmet_sq *sq)
784{
785	struct nvmet_ctrl *ctrl = sq->ctrl;
786
787	/*
788	 * If this is the admin queue, complete all AERs so that our
789	 * queue doesn't have outstanding requests on it.
790	 */
791	if (ctrl && ctrl->sqs && ctrl->sqs[0] == sq)
792		nvmet_async_events_failall(ctrl);
793	percpu_ref_kill_and_confirm(&sq->ref, nvmet_confirm_sq);
794	wait_for_completion(&sq->confirm_done);
795	wait_for_completion(&sq->free_done);
796	percpu_ref_exit(&sq->ref);
797
798	if (ctrl) {
799		/*
800		 * The teardown flow may take some time, and the host may not
801		 * send us keep-alive during this period, hence reset the
802		 * traffic based keep-alive timer so we don't trigger a
803		 * controller teardown as a result of a keep-alive expiration.
804		 */
805		ctrl->reset_tbkas = true;
806		nvmet_ctrl_put(ctrl);
807		sq->ctrl = NULL; /* allows reusing the queue later */
808	}
809}
810EXPORT_SYMBOL_GPL(nvmet_sq_destroy);
811
812static void nvmet_sq_free(struct percpu_ref *ref)
813{
814	struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref);
815
816	complete(&sq->free_done);
817}
818
819int nvmet_sq_init(struct nvmet_sq *sq)
820{
821	int ret;
822
823	ret = percpu_ref_init(&sq->ref, nvmet_sq_free, 0, GFP_KERNEL);
824	if (ret) {
825		pr_err("percpu_ref init failed!\n");
826		return ret;
827	}
828	init_completion(&sq->free_done);
829	init_completion(&sq->confirm_done);
830
831	return 0;
832}
833EXPORT_SYMBOL_GPL(nvmet_sq_init);
834
835static inline u16 nvmet_check_ana_state(struct nvmet_port *port,
836		struct nvmet_ns *ns)
837{
838	enum nvme_ana_state state = port->ana_state[ns->anagrpid];
839
840	if (unlikely(state == NVME_ANA_INACCESSIBLE))
841		return NVME_SC_ANA_INACCESSIBLE;
842	if (unlikely(state == NVME_ANA_PERSISTENT_LOSS))
843		return NVME_SC_ANA_PERSISTENT_LOSS;
844	if (unlikely(state == NVME_ANA_CHANGE))
845		return NVME_SC_ANA_TRANSITION;
846	return 0;
847}
848
849static inline u16 nvmet_io_cmd_check_access(struct nvmet_req *req)
850{
851	if (unlikely(req->ns->readonly)) {
852		switch (req->cmd->common.opcode) {
853		case nvme_cmd_read:
854		case nvme_cmd_flush:
855			break;
856		default:
857			return NVME_SC_NS_WRITE_PROTECTED;
858		}
859	}
860
861	return 0;
862}
863
864static u16 nvmet_parse_io_cmd(struct nvmet_req *req)
865{
866	struct nvme_command *cmd = req->cmd;
867	u16 ret;
868
869	ret = nvmet_check_ctrl_status(req, cmd);
870	if (unlikely(ret))
871		return ret;
872
873	if (nvmet_req_passthru_ctrl(req))
874		return nvmet_parse_passthru_io_cmd(req);
875
876	req->ns = nvmet_find_namespace(req->sq->ctrl, cmd->rw.nsid);
877	if (unlikely(!req->ns)) {
878		req->error_loc = offsetof(struct nvme_common_command, nsid);
879		return NVME_SC_INVALID_NS | NVME_SC_DNR;
880	}
881	ret = nvmet_check_ana_state(req->port, req->ns);
882	if (unlikely(ret)) {
883		req->error_loc = offsetof(struct nvme_common_command, nsid);
884		return ret;
885	}
886	ret = nvmet_io_cmd_check_access(req);
887	if (unlikely(ret)) {
888		req->error_loc = offsetof(struct nvme_common_command, nsid);
889		return ret;
890	}
891
892	if (req->ns->file)
893		return nvmet_file_parse_io_cmd(req);
894	else
895		return nvmet_bdev_parse_io_cmd(req);
896}
897
898bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
899		struct nvmet_sq *sq, const struct nvmet_fabrics_ops *ops)
900{
901	u8 flags = req->cmd->common.flags;
902	u16 status;
903
904	req->cq = cq;
905	req->sq = sq;
906	req->ops = ops;
907	req->sg = NULL;
908	req->metadata_sg = NULL;
909	req->sg_cnt = 0;
910	req->metadata_sg_cnt = 0;
911	req->transfer_len = 0;
912	req->metadata_len = 0;
913	req->cqe->status = 0;
914	req->cqe->sq_head = 0;
915	req->ns = NULL;
916	req->error_loc = NVMET_NO_ERROR_LOC;
917	req->error_slba = 0;
918
919	/* no support for fused commands yet */
920	if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) {
921		req->error_loc = offsetof(struct nvme_common_command, flags);
922		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
923		goto fail;
924	}
925
926	/*
927	 * For fabrics, PSDT field shall describe metadata pointer (MPTR) that
928	 * contains an address of a single contiguous physical buffer that is
929	 * byte aligned.
930	 */
931	if (unlikely((flags & NVME_CMD_SGL_ALL) != NVME_CMD_SGL_METABUF)) {
932		req->error_loc = offsetof(struct nvme_common_command, flags);
933		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
934		goto fail;
935	}
936
937	if (unlikely(!req->sq->ctrl))
938		/* will return an error for any non-connect command: */
939		status = nvmet_parse_connect_cmd(req);
940	else if (likely(req->sq->qid != 0))
941		status = nvmet_parse_io_cmd(req);
942	else
943		status = nvmet_parse_admin_cmd(req);
944
945	if (status)
946		goto fail;
947
948	trace_nvmet_req_init(req, req->cmd);
949
950	if (unlikely(!percpu_ref_tryget_live(&sq->ref))) {
951		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
952		goto fail;
953	}
954
955	if (sq->ctrl)
956		sq->ctrl->reset_tbkas = true;
957
958	return true;
959
960fail:
961	__nvmet_req_complete(req, status);
962	return false;
963}
964EXPORT_SYMBOL_GPL(nvmet_req_init);
965
966void nvmet_req_uninit(struct nvmet_req *req)
967{
968	percpu_ref_put(&req->sq->ref);
969	if (req->ns)
970		nvmet_put_namespace(req->ns);
971}
972EXPORT_SYMBOL_GPL(nvmet_req_uninit);
973
974bool nvmet_check_transfer_len(struct nvmet_req *req, size_t len)
975{
976	if (unlikely(len != req->transfer_len)) {
977		req->error_loc = offsetof(struct nvme_common_command, dptr);
978		nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR);
979		return false;
980	}
981
982	return true;
983}
984EXPORT_SYMBOL_GPL(nvmet_check_transfer_len);
985
986bool nvmet_check_data_len_lte(struct nvmet_req *req, size_t data_len)
987{
988	if (unlikely(data_len > req->transfer_len)) {
989		req->error_loc = offsetof(struct nvme_common_command, dptr);
990		nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR);
991		return false;
992	}
993
994	return true;
995}
996
997static unsigned int nvmet_data_transfer_len(struct nvmet_req *req)
998{
999	return req->transfer_len - req->metadata_len;
1000}
1001
1002static int nvmet_req_alloc_p2pmem_sgls(struct pci_dev *p2p_dev,
1003		struct nvmet_req *req)
1004{
1005	req->sg = pci_p2pmem_alloc_sgl(p2p_dev, &req->sg_cnt,
1006			nvmet_data_transfer_len(req));
1007	if (!req->sg)
1008		goto out_err;
1009
1010	if (req->metadata_len) {
1011		req->metadata_sg = pci_p2pmem_alloc_sgl(p2p_dev,
1012				&req->metadata_sg_cnt, req->metadata_len);
1013		if (!req->metadata_sg)
1014			goto out_free_sg;
1015	}
1016
1017	req->p2p_dev = p2p_dev;
1018
1019	return 0;
1020out_free_sg:
1021	pci_p2pmem_free_sgl(req->p2p_dev, req->sg);
1022out_err:
1023	return -ENOMEM;
1024}
1025
1026static struct pci_dev *nvmet_req_find_p2p_dev(struct nvmet_req *req)
1027{
1028	if (!IS_ENABLED(CONFIG_PCI_P2PDMA) ||
1029	    !req->sq->ctrl || !req->sq->qid || !req->ns)
1030		return NULL;
1031	return radix_tree_lookup(&req->sq->ctrl->p2p_ns_map, req->ns->nsid);
1032}
1033
1034int nvmet_req_alloc_sgls(struct nvmet_req *req)
1035{
1036	struct pci_dev *p2p_dev = nvmet_req_find_p2p_dev(req);
1037
1038	if (p2p_dev && !nvmet_req_alloc_p2pmem_sgls(p2p_dev, req))
1039		return 0;
1040
1041	req->sg = sgl_alloc(nvmet_data_transfer_len(req), GFP_KERNEL,
1042			    &req->sg_cnt);
1043	if (unlikely(!req->sg))
1044		goto out;
1045
1046	if (req->metadata_len) {
1047		req->metadata_sg = sgl_alloc(req->metadata_len, GFP_KERNEL,
1048					     &req->metadata_sg_cnt);
1049		if (unlikely(!req->metadata_sg))
1050			goto out_free;
1051	}
1052
1053	return 0;
1054out_free:
1055	sgl_free(req->sg);
1056out:
1057	return -ENOMEM;
1058}
1059EXPORT_SYMBOL_GPL(nvmet_req_alloc_sgls);
1060
1061void nvmet_req_free_sgls(struct nvmet_req *req)
1062{
1063	if (req->p2p_dev) {
1064		pci_p2pmem_free_sgl(req->p2p_dev, req->sg);
1065		if (req->metadata_sg)
1066			pci_p2pmem_free_sgl(req->p2p_dev, req->metadata_sg);
1067		req->p2p_dev = NULL;
1068	} else {
1069		sgl_free(req->sg);
1070		if (req->metadata_sg)
1071			sgl_free(req->metadata_sg);
1072	}
1073
1074	req->sg = NULL;
1075	req->metadata_sg = NULL;
1076	req->sg_cnt = 0;
1077	req->metadata_sg_cnt = 0;
1078}
1079EXPORT_SYMBOL_GPL(nvmet_req_free_sgls);
1080
1081static inline bool nvmet_cc_en(u32 cc)
1082{
1083	return (cc >> NVME_CC_EN_SHIFT) & 0x1;
1084}
1085
1086static inline u8 nvmet_cc_css(u32 cc)
1087{
1088	return (cc >> NVME_CC_CSS_SHIFT) & 0x7;
1089}
1090
1091static inline u8 nvmet_cc_mps(u32 cc)
1092{
1093	return (cc >> NVME_CC_MPS_SHIFT) & 0xf;
1094}
1095
1096static inline u8 nvmet_cc_ams(u32 cc)
1097{
1098	return (cc >> NVME_CC_AMS_SHIFT) & 0x7;
1099}
1100
1101static inline u8 nvmet_cc_shn(u32 cc)
1102{
1103	return (cc >> NVME_CC_SHN_SHIFT) & 0x3;
1104}
1105
1106static inline u8 nvmet_cc_iosqes(u32 cc)
1107{
1108	return (cc >> NVME_CC_IOSQES_SHIFT) & 0xf;
1109}
1110
1111static inline u8 nvmet_cc_iocqes(u32 cc)
1112{
1113	return (cc >> NVME_CC_IOCQES_SHIFT) & 0xf;
1114}
1115
1116static void nvmet_start_ctrl(struct nvmet_ctrl *ctrl)
1117{
1118	lockdep_assert_held(&ctrl->lock);
1119
1120	/*
1121	 * Only I/O controllers should verify iosqes,iocqes.
1122	 * Strictly speaking, the spec says a discovery controller
1123	 * should verify iosqes,iocqes are zeroed, however that
1124	 * would break backwards compatibility, so don't enforce it.
1125	 */
1126	if (ctrl->subsys->type != NVME_NQN_DISC &&
1127	    (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES ||
1128	     nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES)) {
1129		ctrl->csts = NVME_CSTS_CFS;
1130		return;
1131	}
1132
1133	if (nvmet_cc_mps(ctrl->cc) != 0 ||
1134	    nvmet_cc_ams(ctrl->cc) != 0 ||
1135	    nvmet_cc_css(ctrl->cc) != 0) {
1136		ctrl->csts = NVME_CSTS_CFS;
1137		return;
1138	}
1139
1140	ctrl->csts = NVME_CSTS_RDY;
1141
1142	/*
1143	 * Controllers that are not yet enabled should not really enforce the
1144	 * keep alive timeout, but we still want to track a timeout and cleanup
1145	 * in case a host died before it enabled the controller.  Hence, simply
1146	 * reset the keep alive timer when the controller is enabled.
1147	 */
1148	if (ctrl->kato)
1149		mod_delayed_work(system_wq, &ctrl->ka_work, ctrl->kato * HZ);
1150}
1151
1152static void nvmet_clear_ctrl(struct nvmet_ctrl *ctrl)
1153{
1154	lockdep_assert_held(&ctrl->lock);
1155
1156	/* XXX: tear down queues? */
1157	ctrl->csts &= ~NVME_CSTS_RDY;
1158	ctrl->cc = 0;
1159}
1160
1161void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new)
1162{
1163	u32 old;
1164
1165	mutex_lock(&ctrl->lock);
1166	old = ctrl->cc;
1167	ctrl->cc = new;
1168
1169	if (nvmet_cc_en(new) && !nvmet_cc_en(old))
1170		nvmet_start_ctrl(ctrl);
1171	if (!nvmet_cc_en(new) && nvmet_cc_en(old))
1172		nvmet_clear_ctrl(ctrl);
1173	if (nvmet_cc_shn(new) && !nvmet_cc_shn(old)) {
1174		nvmet_clear_ctrl(ctrl);
1175		ctrl->csts |= NVME_CSTS_SHST_CMPLT;
1176	}
1177	if (!nvmet_cc_shn(new) && nvmet_cc_shn(old))
1178		ctrl->csts &= ~NVME_CSTS_SHST_CMPLT;
1179	mutex_unlock(&ctrl->lock);
1180}
1181
1182static void nvmet_init_cap(struct nvmet_ctrl *ctrl)
1183{
1184	/* command sets supported: NVMe command set: */
1185	ctrl->cap = (1ULL << 37);
1186	/* CC.EN timeout in 500msec units: */
1187	ctrl->cap |= (15ULL << 24);
1188	/* maximum queue entries supported: */
1189	ctrl->cap |= NVMET_QUEUE_SIZE - 1;
1190}
1191
1192struct nvmet_ctrl *nvmet_ctrl_find_get(const char *subsysnqn,
1193				       const char *hostnqn, u16 cntlid,
1194				       struct nvmet_req *req)
1195{
1196	struct nvmet_ctrl *ctrl = NULL;
1197	struct nvmet_subsys *subsys;
1198
1199	subsys = nvmet_find_get_subsys(req->port, subsysnqn);
1200	if (!subsys) {
1201		pr_warn("connect request for invalid subsystem %s!\n",
1202			subsysnqn);
1203		req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn);
1204		goto out;
1205	}
1206
1207	mutex_lock(&subsys->lock);
1208	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
1209		if (ctrl->cntlid == cntlid) {
1210			if (strncmp(hostnqn, ctrl->hostnqn, NVMF_NQN_SIZE)) {
1211				pr_warn("hostnqn mismatch.\n");
1212				continue;
1213			}
1214			if (!kref_get_unless_zero(&ctrl->ref))
1215				continue;
1216
1217			/* ctrl found */
1218			goto found;
1219		}
1220	}
1221
1222	ctrl = NULL; /* ctrl not found */
1223	pr_warn("could not find controller %d for subsys %s / host %s\n",
1224		cntlid, subsysnqn, hostnqn);
1225	req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(cntlid);
1226
1227found:
1228	mutex_unlock(&subsys->lock);
1229	nvmet_subsys_put(subsys);
1230out:
1231	return ctrl;
1232}
1233
1234u16 nvmet_check_ctrl_status(struct nvmet_req *req, struct nvme_command *cmd)
1235{
1236	if (unlikely(!(req->sq->ctrl->cc & NVME_CC_ENABLE))) {
1237		pr_err("got cmd %d while CC.EN == 0 on qid = %d\n",
1238		       cmd->common.opcode, req->sq->qid);
1239		return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
1240	}
1241
1242	if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) {
1243		pr_err("got cmd %d while CSTS.RDY == 0 on qid = %d\n",
1244		       cmd->common.opcode, req->sq->qid);
1245		return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR;
1246	}
1247	return 0;
1248}
1249
1250bool nvmet_host_allowed(struct nvmet_subsys *subsys, const char *hostnqn)
1251{
1252	struct nvmet_host_link *p;
1253
1254	lockdep_assert_held(&nvmet_config_sem);
1255
1256	if (subsys->allow_any_host)
1257		return true;
1258
1259	if (subsys->type == NVME_NQN_DISC) /* allow all access to disc subsys */
1260		return true;
1261
1262	list_for_each_entry(p, &subsys->hosts, entry) {
1263		if (!strcmp(nvmet_host_name(p->host), hostnqn))
1264			return true;
1265	}
1266
1267	return false;
1268}
1269
1270/*
1271 * Note: ctrl->subsys->lock should be held when calling this function
1272 */
1273static void nvmet_setup_p2p_ns_map(struct nvmet_ctrl *ctrl,
1274		struct nvmet_req *req)
1275{
1276	struct nvmet_ns *ns;
1277	unsigned long idx;
1278
1279	if (!req->p2p_client)
1280		return;
1281
1282	ctrl->p2p_client = get_device(req->p2p_client);
1283
1284	xa_for_each(&ctrl->subsys->namespaces, idx, ns)
1285		nvmet_p2pmem_ns_add_p2p(ctrl, ns);
1286}
1287
1288/*
1289 * Note: ctrl->subsys->lock should be held when calling this function
1290 */
1291static void nvmet_release_p2p_ns_map(struct nvmet_ctrl *ctrl)
1292{
1293	struct radix_tree_iter iter;
1294	void __rcu **slot;
1295
1296	radix_tree_for_each_slot(slot, &ctrl->p2p_ns_map, &iter, 0)
1297		pci_dev_put(radix_tree_deref_slot(slot));
1298
1299	put_device(ctrl->p2p_client);
1300}
1301
1302static void nvmet_fatal_error_handler(struct work_struct *work)
1303{
1304	struct nvmet_ctrl *ctrl =
1305			container_of(work, struct nvmet_ctrl, fatal_err_work);
1306
1307	pr_err("ctrl %d fatal error occurred!\n", ctrl->cntlid);
1308	ctrl->ops->delete_ctrl(ctrl);
1309}
1310
1311u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
1312		struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp)
1313{
1314	struct nvmet_subsys *subsys;
1315	struct nvmet_ctrl *ctrl;
1316	int ret;
1317	u16 status;
1318
1319	status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1320	subsys = nvmet_find_get_subsys(req->port, subsysnqn);
1321	if (!subsys) {
1322		pr_warn("connect request for invalid subsystem %s!\n",
1323			subsysnqn);
1324		req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn);
1325		goto out;
1326	}
1327
1328	status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
1329	down_read(&nvmet_config_sem);
1330	if (!nvmet_host_allowed(subsys, hostnqn)) {
1331		pr_info("connect by host %s for subsystem %s not allowed\n",
1332			hostnqn, subsysnqn);
1333		req->cqe->result.u32 = IPO_IATTR_CONNECT_DATA(hostnqn);
1334		up_read(&nvmet_config_sem);
1335		status = NVME_SC_CONNECT_INVALID_HOST | NVME_SC_DNR;
1336		goto out_put_subsystem;
1337	}
1338	up_read(&nvmet_config_sem);
1339
1340	status = NVME_SC_INTERNAL;
1341	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
1342	if (!ctrl)
1343		goto out_put_subsystem;
1344	mutex_init(&ctrl->lock);
1345
1346	nvmet_init_cap(ctrl);
1347
1348	ctrl->port = req->port;
1349
1350	INIT_WORK(&ctrl->async_event_work, nvmet_async_event_work);
1351	INIT_LIST_HEAD(&ctrl->async_events);
1352	INIT_RADIX_TREE(&ctrl->p2p_ns_map, GFP_KERNEL);
1353	INIT_WORK(&ctrl->fatal_err_work, nvmet_fatal_error_handler);
1354
1355	memcpy(ctrl->subsysnqn, subsysnqn, NVMF_NQN_SIZE);
1356	memcpy(ctrl->hostnqn, hostnqn, NVMF_NQN_SIZE);
1357
1358	kref_init(&ctrl->ref);
1359	ctrl->subsys = subsys;
1360	WRITE_ONCE(ctrl->aen_enabled, NVMET_AEN_CFG_OPTIONAL);
1361
1362	ctrl->changed_ns_list = kmalloc_array(NVME_MAX_CHANGED_NAMESPACES,
1363			sizeof(__le32), GFP_KERNEL);
1364	if (!ctrl->changed_ns_list)
1365		goto out_free_ctrl;
1366
1367	ctrl->sqs = kcalloc(subsys->max_qid + 1,
1368			sizeof(struct nvmet_sq *),
1369			GFP_KERNEL);
1370	if (!ctrl->sqs)
1371		goto out_free_changed_ns_list;
1372
1373	if (subsys->cntlid_min > subsys->cntlid_max)
1374		goto out_free_sqs;
1375
1376	ret = ida_simple_get(&cntlid_ida,
1377			     subsys->cntlid_min, subsys->cntlid_max,
1378			     GFP_KERNEL);
1379	if (ret < 0) {
1380		status = NVME_SC_CONNECT_CTRL_BUSY | NVME_SC_DNR;
1381		goto out_free_sqs;
1382	}
1383	ctrl->cntlid = ret;
1384
1385	ctrl->ops = req->ops;
1386
1387	/*
1388	 * Discovery controllers may use some arbitrary high value
1389	 * in order to cleanup stale discovery sessions
1390	 */
1391	if ((ctrl->subsys->type == NVME_NQN_DISC) && !kato)
1392		kato = NVMET_DISC_KATO_MS;
1393
1394	/* keep-alive timeout in seconds */
1395	ctrl->kato = DIV_ROUND_UP(kato, 1000);
1396
1397	ctrl->err_counter = 0;
1398	spin_lock_init(&ctrl->error_lock);
1399
1400	nvmet_start_keep_alive_timer(ctrl);
1401
1402	mutex_lock(&subsys->lock);
1403	list_add_tail(&ctrl->subsys_entry, &subsys->ctrls);
1404	nvmet_setup_p2p_ns_map(ctrl, req);
1405	mutex_unlock(&subsys->lock);
1406
1407	*ctrlp = ctrl;
1408	return 0;
1409
1410out_free_sqs:
1411	kfree(ctrl->sqs);
1412out_free_changed_ns_list:
1413	kfree(ctrl->changed_ns_list);
1414out_free_ctrl:
1415	kfree(ctrl);
1416out_put_subsystem:
1417	nvmet_subsys_put(subsys);
1418out:
1419	return status;
1420}
1421
1422static void nvmet_ctrl_free(struct kref *ref)
1423{
1424	struct nvmet_ctrl *ctrl = container_of(ref, struct nvmet_ctrl, ref);
1425	struct nvmet_subsys *subsys = ctrl->subsys;
1426
1427	mutex_lock(&subsys->lock);
1428	nvmet_release_p2p_ns_map(ctrl);
1429	list_del(&ctrl->subsys_entry);
1430	mutex_unlock(&subsys->lock);
1431
1432	nvmet_stop_keep_alive_timer(ctrl);
1433
1434	flush_work(&ctrl->async_event_work);
1435	cancel_work_sync(&ctrl->fatal_err_work);
1436
1437	ida_simple_remove(&cntlid_ida, ctrl->cntlid);
1438
1439	nvmet_async_events_free(ctrl);
1440	kfree(ctrl->sqs);
1441	kfree(ctrl->changed_ns_list);
1442	kfree(ctrl);
1443
1444	nvmet_subsys_put(subsys);
1445}
1446
1447void nvmet_ctrl_put(struct nvmet_ctrl *ctrl)
1448{
1449	kref_put(&ctrl->ref, nvmet_ctrl_free);
1450}
1451
1452void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl)
1453{
1454	mutex_lock(&ctrl->lock);
1455	if (!(ctrl->csts & NVME_CSTS_CFS)) {
1456		ctrl->csts |= NVME_CSTS_CFS;
1457		schedule_work(&ctrl->fatal_err_work);
1458	}
1459	mutex_unlock(&ctrl->lock);
1460}
1461EXPORT_SYMBOL_GPL(nvmet_ctrl_fatal_error);
1462
1463static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
1464		const char *subsysnqn)
1465{
1466	struct nvmet_subsys_link *p;
1467
1468	if (!port)
1469		return NULL;
1470
1471	if (!strcmp(NVME_DISC_SUBSYS_NAME, subsysnqn)) {
1472		if (!kref_get_unless_zero(&nvmet_disc_subsys->ref))
1473			return NULL;
1474		return nvmet_disc_subsys;
1475	}
1476
1477	down_read(&nvmet_config_sem);
1478	list_for_each_entry(p, &port->subsystems, entry) {
1479		if (!strncmp(p->subsys->subsysnqn, subsysnqn,
1480				NVMF_NQN_SIZE)) {
1481			if (!kref_get_unless_zero(&p->subsys->ref))
1482				break;
1483			up_read(&nvmet_config_sem);
1484			return p->subsys;
1485		}
1486	}
1487	up_read(&nvmet_config_sem);
1488	return NULL;
1489}
1490
1491struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
1492		enum nvme_subsys_type type)
1493{
1494	struct nvmet_subsys *subsys;
1495
1496	subsys = kzalloc(sizeof(*subsys), GFP_KERNEL);
1497	if (!subsys)
1498		return ERR_PTR(-ENOMEM);
1499
1500	subsys->ver = NVMET_DEFAULT_VS;
1501	/* generate a random serial number as our controllers are ephemeral: */
1502	get_random_bytes(&subsys->serial, sizeof(subsys->serial));
1503
1504	switch (type) {
1505	case NVME_NQN_NVME:
1506		subsys->max_qid = NVMET_NR_QUEUES;
1507		break;
1508	case NVME_NQN_DISC:
1509		subsys->max_qid = 0;
1510		break;
1511	default:
1512		pr_err("%s: Unknown Subsystem type - %d\n", __func__, type);
1513		kfree(subsys);
1514		return ERR_PTR(-EINVAL);
1515	}
1516	subsys->type = type;
1517	subsys->subsysnqn = kstrndup(subsysnqn, NVMF_NQN_SIZE,
1518			GFP_KERNEL);
1519	if (!subsys->subsysnqn) {
1520		kfree(subsys);
1521		return ERR_PTR(-ENOMEM);
1522	}
1523	subsys->cntlid_min = NVME_CNTLID_MIN;
1524	subsys->cntlid_max = NVME_CNTLID_MAX;
1525	kref_init(&subsys->ref);
1526
1527	mutex_init(&subsys->lock);
1528	xa_init(&subsys->namespaces);
1529	INIT_LIST_HEAD(&subsys->ctrls);
1530	INIT_LIST_HEAD(&subsys->hosts);
1531
1532	return subsys;
1533}
1534
1535static void nvmet_subsys_free(struct kref *ref)
1536{
1537	struct nvmet_subsys *subsys =
1538		container_of(ref, struct nvmet_subsys, ref);
1539
1540	WARN_ON_ONCE(!xa_empty(&subsys->namespaces));
1541
1542	xa_destroy(&subsys->namespaces);
1543	nvmet_passthru_subsys_free(subsys);
1544
1545	kfree(subsys->subsysnqn);
1546	kfree_rcu(subsys->model, rcuhead);
1547	kfree(subsys);
1548}
1549
1550void nvmet_subsys_del_ctrls(struct nvmet_subsys *subsys)
1551{
1552	struct nvmet_ctrl *ctrl;
1553
1554	mutex_lock(&subsys->lock);
1555	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
1556		ctrl->ops->delete_ctrl(ctrl);
1557	mutex_unlock(&subsys->lock);
1558}
1559
1560void nvmet_subsys_put(struct nvmet_subsys *subsys)
1561{
1562	kref_put(&subsys->ref, nvmet_subsys_free);
1563}
1564
1565static int __init nvmet_init(void)
1566{
1567	int error;
1568
1569	nvmet_ana_group_enabled[NVMET_DEFAULT_ANA_GRPID] = 1;
1570
1571	buffered_io_wq = alloc_workqueue("nvmet-buffered-io-wq",
1572			WQ_MEM_RECLAIM, 0);
1573	if (!buffered_io_wq) {
1574		error = -ENOMEM;
1575		goto out;
1576	}
1577
1578	error = nvmet_init_discovery();
1579	if (error)
1580		goto out_free_work_queue;
1581
1582	error = nvmet_init_configfs();
1583	if (error)
1584		goto out_exit_discovery;
1585	return 0;
1586
1587out_exit_discovery:
1588	nvmet_exit_discovery();
1589out_free_work_queue:
1590	destroy_workqueue(buffered_io_wq);
1591out:
1592	return error;
1593}
1594
1595static void __exit nvmet_exit(void)
1596{
1597	nvmet_exit_configfs();
1598	nvmet_exit_discovery();
1599	ida_destroy(&cntlid_ida);
1600	destroy_workqueue(buffered_io_wq);
1601
1602	BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_entry) != 1024);
1603	BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_hdr) != 1024);
1604}
1605
1606module_init(nvmet_init);
1607module_exit(nvmet_exit);
1608
1609MODULE_LICENSE("GPL v2");
1610