xref: /openbmc/linux/drivers/nvme/host/fabrics.c (revision 6fa24b41)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * NVMe over Fabrics common host code.
4  * Copyright (c) 2015-2016 HGST, a Western Digital Company.
5  */
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7 #include <linux/init.h>
8 #include <linux/miscdevice.h>
9 #include <linux/module.h>
10 #include <linux/mutex.h>
11 #include <linux/parser.h>
12 #include <linux/seq_file.h>
13 #include "nvme.h"
14 #include "fabrics.h"
15 
16 static LIST_HEAD(nvmf_transports);
17 static DECLARE_RWSEM(nvmf_transports_rwsem);
18 
19 static LIST_HEAD(nvmf_hosts);
20 static DEFINE_MUTEX(nvmf_hosts_mutex);
21 
22 static struct nvmf_host *nvmf_default_host;
23 
24 static struct nvmf_host *nvmf_host_alloc(const char *hostnqn, uuid_t *id)
25 {
26 	struct nvmf_host *host;
27 
28 	host = kmalloc(sizeof(*host), GFP_KERNEL);
29 	if (!host)
30 		return NULL;
31 
32 	kref_init(&host->ref);
33 	uuid_copy(&host->id, id);
34 	strscpy(host->nqn, hostnqn, NVMF_NQN_SIZE);
35 
36 	return host;
37 }
38 
39 static struct nvmf_host *nvmf_host_add(const char *hostnqn, uuid_t *id)
40 {
41 	struct nvmf_host *host;
42 
43 	mutex_lock(&nvmf_hosts_mutex);
44 
45 	/*
46 	 * We have defined a host as how it is perceived by the target.
47 	 * Therefore, we don't allow different Host NQNs with the same Host ID.
48 	 * Similarly, we do not allow the usage of the same Host NQN with
49 	 * different Host IDs. This'll maintain unambiguous host identification.
50 	 */
51 	list_for_each_entry(host, &nvmf_hosts, list) {
52 		bool same_hostnqn = !strcmp(host->nqn, hostnqn);
53 		bool same_hostid = uuid_equal(&host->id, id);
54 
55 		if (same_hostnqn && same_hostid) {
56 			kref_get(&host->ref);
57 			goto out_unlock;
58 		}
59 		if (same_hostnqn) {
60 			pr_err("found same hostnqn %s but different hostid %pUb\n",
61 			       hostnqn, id);
62 			host = ERR_PTR(-EINVAL);
63 			goto out_unlock;
64 		}
65 		if (same_hostid) {
66 			pr_err("found same hostid %pUb but different hostnqn %s\n",
67 			       id, hostnqn);
68 			host = ERR_PTR(-EINVAL);
69 			goto out_unlock;
70 		}
71 	}
72 
73 	host = nvmf_host_alloc(hostnqn, id);
74 	if (!host) {
75 		host = ERR_PTR(-ENOMEM);
76 		goto out_unlock;
77 	}
78 
79 	list_add_tail(&host->list, &nvmf_hosts);
80 out_unlock:
81 	mutex_unlock(&nvmf_hosts_mutex);
82 	return host;
83 }
84 
85 static struct nvmf_host *nvmf_host_default(void)
86 {
87 	struct nvmf_host *host;
88 	char nqn[NVMF_NQN_SIZE];
89 	uuid_t id;
90 
91 	uuid_gen(&id);
92 	snprintf(nqn, NVMF_NQN_SIZE,
93 		"nqn.2014-08.org.nvmexpress:uuid:%pUb", &id);
94 
95 	host = nvmf_host_alloc(nqn, &id);
96 	if (!host)
97 		return NULL;
98 
99 	mutex_lock(&nvmf_hosts_mutex);
100 	list_add_tail(&host->list, &nvmf_hosts);
101 	mutex_unlock(&nvmf_hosts_mutex);
102 
103 	return host;
104 }
105 
106 static void nvmf_host_destroy(struct kref *ref)
107 {
108 	struct nvmf_host *host = container_of(ref, struct nvmf_host, ref);
109 
110 	mutex_lock(&nvmf_hosts_mutex);
111 	list_del(&host->list);
112 	mutex_unlock(&nvmf_hosts_mutex);
113 
114 	kfree(host);
115 }
116 
117 static void nvmf_host_put(struct nvmf_host *host)
118 {
119 	if (host)
120 		kref_put(&host->ref, nvmf_host_destroy);
121 }
122 
123 /**
124  * nvmf_get_address() -  Get address/port
125  * @ctrl:	Host NVMe controller instance which we got the address
126  * @buf:	OUTPUT parameter that will contain the address/port
127  * @size:	buffer size
128  */
129 int nvmf_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
130 {
131 	int len = 0;
132 
133 	if (ctrl->opts->mask & NVMF_OPT_TRADDR)
134 		len += scnprintf(buf, size, "traddr=%s", ctrl->opts->traddr);
135 	if (ctrl->opts->mask & NVMF_OPT_TRSVCID)
136 		len += scnprintf(buf + len, size - len, "%strsvcid=%s",
137 				(len) ? "," : "", ctrl->opts->trsvcid);
138 	if (ctrl->opts->mask & NVMF_OPT_HOST_TRADDR)
139 		len += scnprintf(buf + len, size - len, "%shost_traddr=%s",
140 				(len) ? "," : "", ctrl->opts->host_traddr);
141 	if (ctrl->opts->mask & NVMF_OPT_HOST_IFACE)
142 		len += scnprintf(buf + len, size - len, "%shost_iface=%s",
143 				(len) ? "," : "", ctrl->opts->host_iface);
144 	len += scnprintf(buf + len, size - len, "\n");
145 
146 	return len;
147 }
148 EXPORT_SYMBOL_GPL(nvmf_get_address);
149 
150 /**
151  * nvmf_reg_read32() -  NVMe Fabrics "Property Get" API function.
152  * @ctrl:	Host NVMe controller instance maintaining the admin
153  *		queue used to submit the property read command to
154  *		the allocated NVMe controller resource on the target system.
155  * @off:	Starting offset value of the targeted property
156  *		register (see the fabrics section of the NVMe standard).
157  * @val:	OUTPUT parameter that will contain the value of
158  *		the property after a successful read.
159  *
160  * Used by the host system to retrieve a 32-bit capsule property value
161  * from an NVMe controller on the target system.
162  *
163  * ("Capsule property" is an "PCIe register concept" applied to the
164  * NVMe fabrics space.)
165  *
166  * Return:
167  *	0: successful read
168  *	> 0: NVMe error status code
169  *	< 0: Linux errno error code
170  */
171 int nvmf_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
172 {
173 	struct nvme_command cmd = { };
174 	union nvme_result res;
175 	int ret;
176 
177 	cmd.prop_get.opcode = nvme_fabrics_command;
178 	cmd.prop_get.fctype = nvme_fabrics_type_property_get;
179 	cmd.prop_get.offset = cpu_to_le32(off);
180 
181 	ret = __nvme_submit_sync_cmd(ctrl->fabrics_q, &cmd, &res, NULL, 0,
182 			NVME_QID_ANY, 0, 0);
183 
184 	if (ret >= 0)
185 		*val = le64_to_cpu(res.u64);
186 	if (unlikely(ret != 0))
187 		dev_err(ctrl->device,
188 			"Property Get error: %d, offset %#x\n",
189 			ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
190 
191 	return ret;
192 }
193 EXPORT_SYMBOL_GPL(nvmf_reg_read32);
194 
195 /**
196  * nvmf_reg_read64() -  NVMe Fabrics "Property Get" API function.
197  * @ctrl:	Host NVMe controller instance maintaining the admin
198  *		queue used to submit the property read command to
199  *		the allocated controller resource on the target system.
200  * @off:	Starting offset value of the targeted property
201  *		register (see the fabrics section of the NVMe standard).
202  * @val:	OUTPUT parameter that will contain the value of
203  *		the property after a successful read.
204  *
205  * Used by the host system to retrieve a 64-bit capsule property value
206  * from an NVMe controller on the target system.
207  *
208  * ("Capsule property" is an "PCIe register concept" applied to the
209  * NVMe fabrics space.)
210  *
211  * Return:
212  *	0: successful read
213  *	> 0: NVMe error status code
214  *	< 0: Linux errno error code
215  */
216 int nvmf_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
217 {
218 	struct nvme_command cmd = { };
219 	union nvme_result res;
220 	int ret;
221 
222 	cmd.prop_get.opcode = nvme_fabrics_command;
223 	cmd.prop_get.fctype = nvme_fabrics_type_property_get;
224 	cmd.prop_get.attrib = 1;
225 	cmd.prop_get.offset = cpu_to_le32(off);
226 
227 	ret = __nvme_submit_sync_cmd(ctrl->fabrics_q, &cmd, &res, NULL, 0,
228 			NVME_QID_ANY, 0, 0);
229 
230 	if (ret >= 0)
231 		*val = le64_to_cpu(res.u64);
232 	if (unlikely(ret != 0))
233 		dev_err(ctrl->device,
234 			"Property Get error: %d, offset %#x\n",
235 			ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
236 	return ret;
237 }
238 EXPORT_SYMBOL_GPL(nvmf_reg_read64);
239 
240 /**
241  * nvmf_reg_write32() -  NVMe Fabrics "Property Write" API function.
242  * @ctrl:	Host NVMe controller instance maintaining the admin
243  *		queue used to submit the property read command to
244  *		the allocated NVMe controller resource on the target system.
245  * @off:	Starting offset value of the targeted property
246  *		register (see the fabrics section of the NVMe standard).
247  * @val:	Input parameter that contains the value to be
248  *		written to the property.
249  *
250  * Used by the NVMe host system to write a 32-bit capsule property value
251  * to an NVMe controller on the target system.
252  *
253  * ("Capsule property" is an "PCIe register concept" applied to the
254  * NVMe fabrics space.)
255  *
256  * Return:
257  *	0: successful write
258  *	> 0: NVMe error status code
259  *	< 0: Linux errno error code
260  */
261 int nvmf_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
262 {
263 	struct nvme_command cmd = { };
264 	int ret;
265 
266 	cmd.prop_set.opcode = nvme_fabrics_command;
267 	cmd.prop_set.fctype = nvme_fabrics_type_property_set;
268 	cmd.prop_set.attrib = 0;
269 	cmd.prop_set.offset = cpu_to_le32(off);
270 	cmd.prop_set.value = cpu_to_le64(val);
271 
272 	ret = __nvme_submit_sync_cmd(ctrl->fabrics_q, &cmd, NULL, NULL, 0,
273 			NVME_QID_ANY, 0, 0);
274 	if (unlikely(ret))
275 		dev_err(ctrl->device,
276 			"Property Set error: %d, offset %#x\n",
277 			ret > 0 ? ret & ~NVME_SC_DNR : ret, off);
278 	return ret;
279 }
280 EXPORT_SYMBOL_GPL(nvmf_reg_write32);
281 
282 /**
283  * nvmf_log_connect_error() - Error-parsing-diagnostic print out function for
284  * 				connect() errors.
285  * @ctrl:	The specific /dev/nvmeX device that had the error.
286  * @errval:	Error code to be decoded in a more human-friendly
287  * 		printout.
288  * @offset:	For use with the NVMe error code
289  * 		NVME_SC_CONNECT_INVALID_PARAM.
290  * @cmd:	This is the SQE portion of a submission capsule.
291  * @data:	This is the "Data" portion of a submission capsule.
292  */
293 static void nvmf_log_connect_error(struct nvme_ctrl *ctrl,
294 		int errval, int offset, struct nvme_command *cmd,
295 		struct nvmf_connect_data *data)
296 {
297 	int err_sctype = errval & ~NVME_SC_DNR;
298 
299 	if (errval < 0) {
300 		dev_err(ctrl->device,
301 			"Connect command failed, errno: %d\n", errval);
302 		return;
303 	}
304 
305 	switch (err_sctype) {
306 	case NVME_SC_CONNECT_INVALID_PARAM:
307 		if (offset >> 16) {
308 			char *inv_data = "Connect Invalid Data Parameter";
309 
310 			switch (offset & 0xffff) {
311 			case (offsetof(struct nvmf_connect_data, cntlid)):
312 				dev_err(ctrl->device,
313 					"%s, cntlid: %d\n",
314 					inv_data, data->cntlid);
315 				break;
316 			case (offsetof(struct nvmf_connect_data, hostnqn)):
317 				dev_err(ctrl->device,
318 					"%s, hostnqn \"%s\"\n",
319 					inv_data, data->hostnqn);
320 				break;
321 			case (offsetof(struct nvmf_connect_data, subsysnqn)):
322 				dev_err(ctrl->device,
323 					"%s, subsysnqn \"%s\"\n",
324 					inv_data, data->subsysnqn);
325 				break;
326 			default:
327 				dev_err(ctrl->device,
328 					"%s, starting byte offset: %d\n",
329 				       inv_data, offset & 0xffff);
330 				break;
331 			}
332 		} else {
333 			char *inv_sqe = "Connect Invalid SQE Parameter";
334 
335 			switch (offset) {
336 			case (offsetof(struct nvmf_connect_command, qid)):
337 				dev_err(ctrl->device,
338 				       "%s, qid %d\n",
339 					inv_sqe, cmd->connect.qid);
340 				break;
341 			default:
342 				dev_err(ctrl->device,
343 					"%s, starting byte offset: %d\n",
344 					inv_sqe, offset);
345 			}
346 		}
347 		break;
348 	case NVME_SC_CONNECT_INVALID_HOST:
349 		dev_err(ctrl->device,
350 			"Connect for subsystem %s is not allowed, hostnqn: %s\n",
351 			data->subsysnqn, data->hostnqn);
352 		break;
353 	case NVME_SC_CONNECT_CTRL_BUSY:
354 		dev_err(ctrl->device,
355 			"Connect command failed: controller is busy or not available\n");
356 		break;
357 	case NVME_SC_CONNECT_FORMAT:
358 		dev_err(ctrl->device,
359 			"Connect incompatible format: %d",
360 			cmd->connect.recfmt);
361 		break;
362 	case NVME_SC_HOST_PATH_ERROR:
363 		dev_err(ctrl->device,
364 			"Connect command failed: host path error\n");
365 		break;
366 	case NVME_SC_AUTH_REQUIRED:
367 		dev_err(ctrl->device,
368 			"Connect command failed: authentication required\n");
369 		break;
370 	default:
371 		dev_err(ctrl->device,
372 			"Connect command failed, error wo/DNR bit: %d\n",
373 			err_sctype);
374 		break;
375 	}
376 }
377 
378 static struct nvmf_connect_data *nvmf_connect_data_prep(struct nvme_ctrl *ctrl,
379 		u16 cntlid)
380 {
381 	struct nvmf_connect_data *data;
382 
383 	data = kzalloc(sizeof(*data), GFP_KERNEL);
384 	if (!data)
385 		return NULL;
386 
387 	uuid_copy(&data->hostid, &ctrl->opts->host->id);
388 	data->cntlid = cpu_to_le16(cntlid);
389 	strncpy(data->subsysnqn, ctrl->opts->subsysnqn, NVMF_NQN_SIZE);
390 	strncpy(data->hostnqn, ctrl->opts->host->nqn, NVMF_NQN_SIZE);
391 
392 	return data;
393 }
394 
395 static void nvmf_connect_cmd_prep(struct nvme_ctrl *ctrl, u16 qid,
396 		struct nvme_command *cmd)
397 {
398 	cmd->connect.opcode = nvme_fabrics_command;
399 	cmd->connect.fctype = nvme_fabrics_type_connect;
400 	cmd->connect.qid = cpu_to_le16(qid);
401 
402 	if (qid) {
403 		cmd->connect.sqsize = cpu_to_le16(ctrl->sqsize);
404 	} else {
405 		cmd->connect.sqsize = cpu_to_le16(NVME_AQ_DEPTH - 1);
406 
407 		/*
408 		 * set keep-alive timeout in seconds granularity (ms * 1000)
409 		 */
410 		cmd->connect.kato = cpu_to_le32(ctrl->kato * 1000);
411 	}
412 
413 	if (ctrl->opts->disable_sqflow)
414 		cmd->connect.cattr |= NVME_CONNECT_DISABLE_SQFLOW;
415 }
416 
417 /**
418  * nvmf_connect_admin_queue() - NVMe Fabrics Admin Queue "Connect"
419  *				API function.
420  * @ctrl:	Host nvme controller instance used to request
421  *              a new NVMe controller allocation on the target
422  *              system and  establish an NVMe Admin connection to
423  *              that controller.
424  *
425  * This function enables an NVMe host device to request a new allocation of
426  * an NVMe controller resource on a target system as well establish a
427  * fabrics-protocol connection of the NVMe Admin queue between the
428  * host system device and the allocated NVMe controller on the
429  * target system via a NVMe Fabrics "Connect" command.
430  *
431  * Return:
432  *	0: success
433  *	> 0: NVMe error status code
434  *	< 0: Linux errno error code
435  *
436  */
437 int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
438 {
439 	struct nvme_command cmd = { };
440 	union nvme_result res;
441 	struct nvmf_connect_data *data;
442 	int ret;
443 	u32 result;
444 
445 	nvmf_connect_cmd_prep(ctrl, 0, &cmd);
446 
447 	data = nvmf_connect_data_prep(ctrl, 0xffff);
448 	if (!data)
449 		return -ENOMEM;
450 
451 	ret = __nvme_submit_sync_cmd(ctrl->fabrics_q, &cmd, &res,
452 			data, sizeof(*data), NVME_QID_ANY, 1,
453 			BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
454 	if (ret) {
455 		nvmf_log_connect_error(ctrl, ret, le32_to_cpu(res.u32),
456 				       &cmd, data);
457 		goto out_free_data;
458 	}
459 
460 	result = le32_to_cpu(res.u32);
461 	ctrl->cntlid = result & 0xFFFF;
462 	if (result & (NVME_CONNECT_AUTHREQ_ATR | NVME_CONNECT_AUTHREQ_ASCR)) {
463 		/* Secure concatenation is not implemented */
464 		if (result & NVME_CONNECT_AUTHREQ_ASCR) {
465 			dev_warn(ctrl->device,
466 				 "qid 0: secure concatenation is not supported\n");
467 			ret = NVME_SC_AUTH_REQUIRED;
468 			goto out_free_data;
469 		}
470 		/* Authentication required */
471 		ret = nvme_auth_negotiate(ctrl, 0);
472 		if (ret) {
473 			dev_warn(ctrl->device,
474 				 "qid 0: authentication setup failed\n");
475 			ret = NVME_SC_AUTH_REQUIRED;
476 			goto out_free_data;
477 		}
478 		ret = nvme_auth_wait(ctrl, 0);
479 		if (ret)
480 			dev_warn(ctrl->device,
481 				 "qid 0: authentication failed\n");
482 		else
483 			dev_info(ctrl->device,
484 				 "qid 0: authenticated\n");
485 	}
486 out_free_data:
487 	kfree(data);
488 	return ret;
489 }
490 EXPORT_SYMBOL_GPL(nvmf_connect_admin_queue);
491 
492 /**
493  * nvmf_connect_io_queue() - NVMe Fabrics I/O Queue "Connect"
494  *			     API function.
495  * @ctrl:	Host nvme controller instance used to establish an
496  *		NVMe I/O queue connection to the already allocated NVMe
497  *		controller on the target system.
498  * @qid:	NVMe I/O queue number for the new I/O connection between
499  *		host and target (note qid == 0 is illegal as this is
500  *		the Admin queue, per NVMe standard).
501  *
502  * This function issues a fabrics-protocol connection
503  * of a NVMe I/O queue (via NVMe Fabrics "Connect" command)
504  * between the host system device and the allocated NVMe controller
505  * on the target system.
506  *
507  * Return:
508  *	0: success
509  *	> 0: NVMe error status code
510  *	< 0: Linux errno error code
511  */
512 int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid)
513 {
514 	struct nvme_command cmd = { };
515 	struct nvmf_connect_data *data;
516 	union nvme_result res;
517 	int ret;
518 	u32 result;
519 
520 	nvmf_connect_cmd_prep(ctrl, qid, &cmd);
521 
522 	data = nvmf_connect_data_prep(ctrl, ctrl->cntlid);
523 	if (!data)
524 		return -ENOMEM;
525 
526 	ret = __nvme_submit_sync_cmd(ctrl->connect_q, &cmd, &res,
527 			data, sizeof(*data), qid, 1,
528 			BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
529 	if (ret) {
530 		nvmf_log_connect_error(ctrl, ret, le32_to_cpu(res.u32),
531 				       &cmd, data);
532 	}
533 	result = le32_to_cpu(res.u32);
534 	if (result & (NVME_CONNECT_AUTHREQ_ATR | NVME_CONNECT_AUTHREQ_ASCR)) {
535 		/* Secure concatenation is not implemented */
536 		if (result & NVME_CONNECT_AUTHREQ_ASCR) {
537 			dev_warn(ctrl->device,
538 				 "qid 0: secure concatenation is not supported\n");
539 			ret = NVME_SC_AUTH_REQUIRED;
540 			goto out_free_data;
541 		}
542 		/* Authentication required */
543 		ret = nvme_auth_negotiate(ctrl, qid);
544 		if (ret) {
545 			dev_warn(ctrl->device,
546 				 "qid %d: authentication setup failed\n", qid);
547 			ret = NVME_SC_AUTH_REQUIRED;
548 		} else {
549 			ret = nvme_auth_wait(ctrl, qid);
550 			if (ret)
551 				dev_warn(ctrl->device,
552 					 "qid %u: authentication failed\n", qid);
553 		}
554 	}
555 out_free_data:
556 	kfree(data);
557 	return ret;
558 }
559 EXPORT_SYMBOL_GPL(nvmf_connect_io_queue);
560 
561 bool nvmf_should_reconnect(struct nvme_ctrl *ctrl)
562 {
563 	if (ctrl->opts->max_reconnects == -1 ||
564 	    ctrl->nr_reconnects < ctrl->opts->max_reconnects)
565 		return true;
566 
567 	return false;
568 }
569 EXPORT_SYMBOL_GPL(nvmf_should_reconnect);
570 
571 /**
572  * nvmf_register_transport() - NVMe Fabrics Library registration function.
573  * @ops:	Transport ops instance to be registered to the
574  *		common fabrics library.
575  *
576  * API function that registers the type of specific transport fabric
577  * being implemented to the common NVMe fabrics library. Part of
578  * the overall init sequence of starting up a fabrics driver.
579  */
580 int nvmf_register_transport(struct nvmf_transport_ops *ops)
581 {
582 	if (!ops->create_ctrl)
583 		return -EINVAL;
584 
585 	down_write(&nvmf_transports_rwsem);
586 	list_add_tail(&ops->entry, &nvmf_transports);
587 	up_write(&nvmf_transports_rwsem);
588 
589 	return 0;
590 }
591 EXPORT_SYMBOL_GPL(nvmf_register_transport);
592 
593 /**
594  * nvmf_unregister_transport() - NVMe Fabrics Library unregistration function.
595  * @ops:	Transport ops instance to be unregistered from the
596  *		common fabrics library.
597  *
598  * Fabrics API function that unregisters the type of specific transport
599  * fabric being implemented from the common NVMe fabrics library.
600  * Part of the overall exit sequence of unloading the implemented driver.
601  */
602 void nvmf_unregister_transport(struct nvmf_transport_ops *ops)
603 {
604 	down_write(&nvmf_transports_rwsem);
605 	list_del(&ops->entry);
606 	up_write(&nvmf_transports_rwsem);
607 }
608 EXPORT_SYMBOL_GPL(nvmf_unregister_transport);
609 
610 static struct nvmf_transport_ops *nvmf_lookup_transport(
611 		struct nvmf_ctrl_options *opts)
612 {
613 	struct nvmf_transport_ops *ops;
614 
615 	lockdep_assert_held(&nvmf_transports_rwsem);
616 
617 	list_for_each_entry(ops, &nvmf_transports, entry) {
618 		if (strcmp(ops->name, opts->transport) == 0)
619 			return ops;
620 	}
621 
622 	return NULL;
623 }
624 
625 static const match_table_t opt_tokens = {
626 	{ NVMF_OPT_TRANSPORT,		"transport=%s"		},
627 	{ NVMF_OPT_TRADDR,		"traddr=%s"		},
628 	{ NVMF_OPT_TRSVCID,		"trsvcid=%s"		},
629 	{ NVMF_OPT_NQN,			"nqn=%s"		},
630 	{ NVMF_OPT_QUEUE_SIZE,		"queue_size=%d"		},
631 	{ NVMF_OPT_NR_IO_QUEUES,	"nr_io_queues=%d"	},
632 	{ NVMF_OPT_RECONNECT_DELAY,	"reconnect_delay=%d"	},
633 	{ NVMF_OPT_CTRL_LOSS_TMO,	"ctrl_loss_tmo=%d"	},
634 	{ NVMF_OPT_KATO,		"keep_alive_tmo=%d"	},
635 	{ NVMF_OPT_HOSTNQN,		"hostnqn=%s"		},
636 	{ NVMF_OPT_HOST_TRADDR,		"host_traddr=%s"	},
637 	{ NVMF_OPT_HOST_IFACE,		"host_iface=%s"		},
638 	{ NVMF_OPT_HOST_ID,		"hostid=%s"		},
639 	{ NVMF_OPT_DUP_CONNECT,		"duplicate_connect"	},
640 	{ NVMF_OPT_DISABLE_SQFLOW,	"disable_sqflow"	},
641 	{ NVMF_OPT_HDR_DIGEST,		"hdr_digest"		},
642 	{ NVMF_OPT_DATA_DIGEST,		"data_digest"		},
643 	{ NVMF_OPT_NR_WRITE_QUEUES,	"nr_write_queues=%d"	},
644 	{ NVMF_OPT_NR_POLL_QUEUES,	"nr_poll_queues=%d"	},
645 	{ NVMF_OPT_TOS,			"tos=%d"		},
646 	{ NVMF_OPT_FAIL_FAST_TMO,	"fast_io_fail_tmo=%d"	},
647 	{ NVMF_OPT_DISCOVERY,		"discovery"		},
648 #ifdef CONFIG_NVME_HOST_AUTH
649 	{ NVMF_OPT_DHCHAP_SECRET,	"dhchap_secret=%s"	},
650 	{ NVMF_OPT_DHCHAP_CTRL_SECRET,	"dhchap_ctrl_secret=%s"	},
651 #endif
652 	{ NVMF_OPT_ERR,			NULL			}
653 };
654 
655 static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
656 		const char *buf)
657 {
658 	substring_t args[MAX_OPT_ARGS];
659 	char *options, *o, *p;
660 	int token, ret = 0;
661 	size_t nqnlen  = 0;
662 	int ctrl_loss_tmo = NVMF_DEF_CTRL_LOSS_TMO;
663 	uuid_t hostid;
664 	char hostnqn[NVMF_NQN_SIZE];
665 
666 	/* Set defaults */
667 	opts->queue_size = NVMF_DEF_QUEUE_SIZE;
668 	opts->nr_io_queues = num_online_cpus();
669 	opts->reconnect_delay = NVMF_DEF_RECONNECT_DELAY;
670 	opts->kato = 0;
671 	opts->duplicate_connect = false;
672 	opts->fast_io_fail_tmo = NVMF_DEF_FAIL_FAST_TMO;
673 	opts->hdr_digest = false;
674 	opts->data_digest = false;
675 	opts->tos = -1; /* < 0 == use transport default */
676 
677 	options = o = kstrdup(buf, GFP_KERNEL);
678 	if (!options)
679 		return -ENOMEM;
680 
681 	/* use default host if not given by user space */
682 	uuid_copy(&hostid, &nvmf_default_host->id);
683 	strscpy(hostnqn, nvmf_default_host->nqn, NVMF_NQN_SIZE);
684 
685 	while ((p = strsep(&o, ",\n")) != NULL) {
686 		if (!*p)
687 			continue;
688 
689 		token = match_token(p, opt_tokens, args);
690 		opts->mask |= token;
691 		switch (token) {
692 		case NVMF_OPT_TRANSPORT:
693 			p = match_strdup(args);
694 			if (!p) {
695 				ret = -ENOMEM;
696 				goto out;
697 			}
698 			kfree(opts->transport);
699 			opts->transport = p;
700 			break;
701 		case NVMF_OPT_NQN:
702 			p = match_strdup(args);
703 			if (!p) {
704 				ret = -ENOMEM;
705 				goto out;
706 			}
707 			kfree(opts->subsysnqn);
708 			opts->subsysnqn = p;
709 			nqnlen = strlen(opts->subsysnqn);
710 			if (nqnlen >= NVMF_NQN_SIZE) {
711 				pr_err("%s needs to be < %d bytes\n",
712 					opts->subsysnqn, NVMF_NQN_SIZE);
713 				ret = -EINVAL;
714 				goto out;
715 			}
716 			opts->discovery_nqn =
717 				!(strcmp(opts->subsysnqn,
718 					 NVME_DISC_SUBSYS_NAME));
719 			break;
720 		case NVMF_OPT_TRADDR:
721 			p = match_strdup(args);
722 			if (!p) {
723 				ret = -ENOMEM;
724 				goto out;
725 			}
726 			kfree(opts->traddr);
727 			opts->traddr = p;
728 			break;
729 		case NVMF_OPT_TRSVCID:
730 			p = match_strdup(args);
731 			if (!p) {
732 				ret = -ENOMEM;
733 				goto out;
734 			}
735 			kfree(opts->trsvcid);
736 			opts->trsvcid = p;
737 			break;
738 		case NVMF_OPT_QUEUE_SIZE:
739 			if (match_int(args, &token)) {
740 				ret = -EINVAL;
741 				goto out;
742 			}
743 			if (token < NVMF_MIN_QUEUE_SIZE ||
744 			    token > NVMF_MAX_QUEUE_SIZE) {
745 				pr_err("Invalid queue_size %d\n", token);
746 				ret = -EINVAL;
747 				goto out;
748 			}
749 			opts->queue_size = token;
750 			break;
751 		case NVMF_OPT_NR_IO_QUEUES:
752 			if (match_int(args, &token)) {
753 				ret = -EINVAL;
754 				goto out;
755 			}
756 			if (token <= 0) {
757 				pr_err("Invalid number of IOQs %d\n", token);
758 				ret = -EINVAL;
759 				goto out;
760 			}
761 			if (opts->discovery_nqn) {
762 				pr_debug("Ignoring nr_io_queues value for discovery controller\n");
763 				break;
764 			}
765 
766 			opts->nr_io_queues = min_t(unsigned int,
767 					num_online_cpus(), token);
768 			break;
769 		case NVMF_OPT_KATO:
770 			if (match_int(args, &token)) {
771 				ret = -EINVAL;
772 				goto out;
773 			}
774 
775 			if (token < 0) {
776 				pr_err("Invalid keep_alive_tmo %d\n", token);
777 				ret = -EINVAL;
778 				goto out;
779 			} else if (token == 0 && !opts->discovery_nqn) {
780 				/* Allowed for debug */
781 				pr_warn("keep_alive_tmo 0 won't execute keep alives!!!\n");
782 			}
783 			opts->kato = token;
784 			break;
785 		case NVMF_OPT_CTRL_LOSS_TMO:
786 			if (match_int(args, &token)) {
787 				ret = -EINVAL;
788 				goto out;
789 			}
790 
791 			if (token < 0)
792 				pr_warn("ctrl_loss_tmo < 0 will reconnect forever\n");
793 			ctrl_loss_tmo = token;
794 			break;
795 		case NVMF_OPT_FAIL_FAST_TMO:
796 			if (match_int(args, &token)) {
797 				ret = -EINVAL;
798 				goto out;
799 			}
800 
801 			if (token >= 0)
802 				pr_warn("I/O fail on reconnect controller after %d sec\n",
803 					token);
804 			else
805 				token = -1;
806 
807 			opts->fast_io_fail_tmo = token;
808 			break;
809 		case NVMF_OPT_HOSTNQN:
810 			if (opts->host) {
811 				pr_err("hostnqn already user-assigned: %s\n",
812 				       opts->host->nqn);
813 				ret = -EADDRINUSE;
814 				goto out;
815 			}
816 			p = match_strdup(args);
817 			if (!p) {
818 				ret = -ENOMEM;
819 				goto out;
820 			}
821 			nqnlen = strlen(p);
822 			if (nqnlen >= NVMF_NQN_SIZE) {
823 				pr_err("%s needs to be < %d bytes\n",
824 					p, NVMF_NQN_SIZE);
825 				kfree(p);
826 				ret = -EINVAL;
827 				goto out;
828 			}
829 			strscpy(hostnqn, p, NVMF_NQN_SIZE);
830 			kfree(p);
831 			break;
832 		case NVMF_OPT_RECONNECT_DELAY:
833 			if (match_int(args, &token)) {
834 				ret = -EINVAL;
835 				goto out;
836 			}
837 			if (token <= 0) {
838 				pr_err("Invalid reconnect_delay %d\n", token);
839 				ret = -EINVAL;
840 				goto out;
841 			}
842 			opts->reconnect_delay = token;
843 			break;
844 		case NVMF_OPT_HOST_TRADDR:
845 			p = match_strdup(args);
846 			if (!p) {
847 				ret = -ENOMEM;
848 				goto out;
849 			}
850 			kfree(opts->host_traddr);
851 			opts->host_traddr = p;
852 			break;
853 		case NVMF_OPT_HOST_IFACE:
854 			p = match_strdup(args);
855 			if (!p) {
856 				ret = -ENOMEM;
857 				goto out;
858 			}
859 			kfree(opts->host_iface);
860 			opts->host_iface = p;
861 			break;
862 		case NVMF_OPT_HOST_ID:
863 			p = match_strdup(args);
864 			if (!p) {
865 				ret = -ENOMEM;
866 				goto out;
867 			}
868 			ret = uuid_parse(p, &hostid);
869 			if (ret) {
870 				pr_err("Invalid hostid %s\n", p);
871 				ret = -EINVAL;
872 				kfree(p);
873 				goto out;
874 			}
875 			kfree(p);
876 			break;
877 		case NVMF_OPT_DUP_CONNECT:
878 			opts->duplicate_connect = true;
879 			break;
880 		case NVMF_OPT_DISABLE_SQFLOW:
881 			opts->disable_sqflow = true;
882 			break;
883 		case NVMF_OPT_HDR_DIGEST:
884 			opts->hdr_digest = true;
885 			break;
886 		case NVMF_OPT_DATA_DIGEST:
887 			opts->data_digest = true;
888 			break;
889 		case NVMF_OPT_NR_WRITE_QUEUES:
890 			if (match_int(args, &token)) {
891 				ret = -EINVAL;
892 				goto out;
893 			}
894 			if (token <= 0) {
895 				pr_err("Invalid nr_write_queues %d\n", token);
896 				ret = -EINVAL;
897 				goto out;
898 			}
899 			opts->nr_write_queues = token;
900 			break;
901 		case NVMF_OPT_NR_POLL_QUEUES:
902 			if (match_int(args, &token)) {
903 				ret = -EINVAL;
904 				goto out;
905 			}
906 			if (token <= 0) {
907 				pr_err("Invalid nr_poll_queues %d\n", token);
908 				ret = -EINVAL;
909 				goto out;
910 			}
911 			opts->nr_poll_queues = token;
912 			break;
913 		case NVMF_OPT_TOS:
914 			if (match_int(args, &token)) {
915 				ret = -EINVAL;
916 				goto out;
917 			}
918 			if (token < 0) {
919 				pr_err("Invalid type of service %d\n", token);
920 				ret = -EINVAL;
921 				goto out;
922 			}
923 			if (token > 255) {
924 				pr_warn("Clamping type of service to 255\n");
925 				token = 255;
926 			}
927 			opts->tos = token;
928 			break;
929 		case NVMF_OPT_DISCOVERY:
930 			opts->discovery_nqn = true;
931 			break;
932 		case NVMF_OPT_DHCHAP_SECRET:
933 			p = match_strdup(args);
934 			if (!p) {
935 				ret = -ENOMEM;
936 				goto out;
937 			}
938 			if (strlen(p) < 11 || strncmp(p, "DHHC-1:", 7)) {
939 				pr_err("Invalid DH-CHAP secret %s\n", p);
940 				ret = -EINVAL;
941 				goto out;
942 			}
943 			kfree(opts->dhchap_secret);
944 			opts->dhchap_secret = p;
945 			break;
946 		case NVMF_OPT_DHCHAP_CTRL_SECRET:
947 			p = match_strdup(args);
948 			if (!p) {
949 				ret = -ENOMEM;
950 				goto out;
951 			}
952 			if (strlen(p) < 11 || strncmp(p, "DHHC-1:", 7)) {
953 				pr_err("Invalid DH-CHAP secret %s\n", p);
954 				ret = -EINVAL;
955 				goto out;
956 			}
957 			kfree(opts->dhchap_ctrl_secret);
958 			opts->dhchap_ctrl_secret = p;
959 			break;
960 		default:
961 			pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
962 				p);
963 			ret = -EINVAL;
964 			goto out;
965 		}
966 	}
967 
968 	if (opts->discovery_nqn) {
969 		opts->nr_io_queues = 0;
970 		opts->nr_write_queues = 0;
971 		opts->nr_poll_queues = 0;
972 		opts->duplicate_connect = true;
973 	} else {
974 		if (!opts->kato)
975 			opts->kato = NVME_DEFAULT_KATO;
976 	}
977 	if (ctrl_loss_tmo < 0) {
978 		opts->max_reconnects = -1;
979 	} else {
980 		opts->max_reconnects = DIV_ROUND_UP(ctrl_loss_tmo,
981 						opts->reconnect_delay);
982 		if (ctrl_loss_tmo < opts->fast_io_fail_tmo)
983 			pr_warn("failfast tmo (%d) larger than controller loss tmo (%d)\n",
984 				opts->fast_io_fail_tmo, ctrl_loss_tmo);
985 	}
986 
987 	opts->host = nvmf_host_add(hostnqn, &hostid);
988 	if (IS_ERR(opts->host)) {
989 		ret = PTR_ERR(opts->host);
990 		opts->host = NULL;
991 		goto out;
992 	}
993 
994 out:
995 	kfree(options);
996 	return ret;
997 }
998 
999 void nvmf_set_io_queues(struct nvmf_ctrl_options *opts, u32 nr_io_queues,
1000 			u32 io_queues[HCTX_MAX_TYPES])
1001 {
1002 	if (opts->nr_write_queues && opts->nr_io_queues < nr_io_queues) {
1003 		/*
1004 		 * separate read/write queues
1005 		 * hand out dedicated default queues only after we have
1006 		 * sufficient read queues.
1007 		 */
1008 		io_queues[HCTX_TYPE_READ] = opts->nr_io_queues;
1009 		nr_io_queues -= io_queues[HCTX_TYPE_READ];
1010 		io_queues[HCTX_TYPE_DEFAULT] =
1011 			min(opts->nr_write_queues, nr_io_queues);
1012 		nr_io_queues -= io_queues[HCTX_TYPE_DEFAULT];
1013 	} else {
1014 		/*
1015 		 * shared read/write queues
1016 		 * either no write queues were requested, or we don't have
1017 		 * sufficient queue count to have dedicated default queues.
1018 		 */
1019 		io_queues[HCTX_TYPE_DEFAULT] =
1020 			min(opts->nr_io_queues, nr_io_queues);
1021 		nr_io_queues -= io_queues[HCTX_TYPE_DEFAULT];
1022 	}
1023 
1024 	if (opts->nr_poll_queues && nr_io_queues) {
1025 		/* map dedicated poll queues only if we have queues left */
1026 		io_queues[HCTX_TYPE_POLL] =
1027 			min(opts->nr_poll_queues, nr_io_queues);
1028 	}
1029 }
1030 EXPORT_SYMBOL_GPL(nvmf_set_io_queues);
1031 
1032 void nvmf_map_queues(struct blk_mq_tag_set *set, struct nvme_ctrl *ctrl,
1033 		     u32 io_queues[HCTX_MAX_TYPES])
1034 {
1035 	struct nvmf_ctrl_options *opts = ctrl->opts;
1036 
1037 	if (opts->nr_write_queues && io_queues[HCTX_TYPE_READ]) {
1038 		/* separate read/write queues */
1039 		set->map[HCTX_TYPE_DEFAULT].nr_queues =
1040 			io_queues[HCTX_TYPE_DEFAULT];
1041 		set->map[HCTX_TYPE_DEFAULT].queue_offset = 0;
1042 		set->map[HCTX_TYPE_READ].nr_queues =
1043 			io_queues[HCTX_TYPE_READ];
1044 		set->map[HCTX_TYPE_READ].queue_offset =
1045 			io_queues[HCTX_TYPE_DEFAULT];
1046 	} else {
1047 		/* shared read/write queues */
1048 		set->map[HCTX_TYPE_DEFAULT].nr_queues =
1049 			io_queues[HCTX_TYPE_DEFAULT];
1050 		set->map[HCTX_TYPE_DEFAULT].queue_offset = 0;
1051 		set->map[HCTX_TYPE_READ].nr_queues =
1052 			io_queues[HCTX_TYPE_DEFAULT];
1053 		set->map[HCTX_TYPE_READ].queue_offset = 0;
1054 	}
1055 
1056 	blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]);
1057 	blk_mq_map_queues(&set->map[HCTX_TYPE_READ]);
1058 	if (opts->nr_poll_queues && io_queues[HCTX_TYPE_POLL]) {
1059 		/* map dedicated poll queues only if we have queues left */
1060 		set->map[HCTX_TYPE_POLL].nr_queues = io_queues[HCTX_TYPE_POLL];
1061 		set->map[HCTX_TYPE_POLL].queue_offset =
1062 			io_queues[HCTX_TYPE_DEFAULT] +
1063 			io_queues[HCTX_TYPE_READ];
1064 		blk_mq_map_queues(&set->map[HCTX_TYPE_POLL]);
1065 	}
1066 
1067 	dev_info(ctrl->device,
1068 		"mapped %d/%d/%d default/read/poll queues.\n",
1069 		io_queues[HCTX_TYPE_DEFAULT],
1070 		io_queues[HCTX_TYPE_READ],
1071 		io_queues[HCTX_TYPE_POLL]);
1072 }
1073 EXPORT_SYMBOL_GPL(nvmf_map_queues);
1074 
1075 static int nvmf_check_required_opts(struct nvmf_ctrl_options *opts,
1076 		unsigned int required_opts)
1077 {
1078 	if ((opts->mask & required_opts) != required_opts) {
1079 		unsigned int i;
1080 
1081 		for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
1082 			if ((opt_tokens[i].token & required_opts) &&
1083 			    !(opt_tokens[i].token & opts->mask)) {
1084 				pr_warn("missing parameter '%s'\n",
1085 					opt_tokens[i].pattern);
1086 			}
1087 		}
1088 
1089 		return -EINVAL;
1090 	}
1091 
1092 	return 0;
1093 }
1094 
1095 bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
1096 		struct nvmf_ctrl_options *opts)
1097 {
1098 	if (!nvmf_ctlr_matches_baseopts(ctrl, opts) ||
1099 	    strcmp(opts->traddr, ctrl->opts->traddr) ||
1100 	    strcmp(opts->trsvcid, ctrl->opts->trsvcid))
1101 		return false;
1102 
1103 	/*
1104 	 * Checking the local address or host interfaces is rough.
1105 	 *
1106 	 * In most cases, none is specified and the host port or
1107 	 * host interface is selected by the stack.
1108 	 *
1109 	 * Assume no match if:
1110 	 * -  local address or host interface is specified and address
1111 	 *    or host interface is not the same
1112 	 * -  local address or host interface is not specified but
1113 	 *    remote is, or vice versa (admin using specific
1114 	 *    host_traddr/host_iface when it matters).
1115 	 */
1116 	if ((opts->mask & NVMF_OPT_HOST_TRADDR) &&
1117 	    (ctrl->opts->mask & NVMF_OPT_HOST_TRADDR)) {
1118 		if (strcmp(opts->host_traddr, ctrl->opts->host_traddr))
1119 			return false;
1120 	} else if ((opts->mask & NVMF_OPT_HOST_TRADDR) ||
1121 		   (ctrl->opts->mask & NVMF_OPT_HOST_TRADDR)) {
1122 		return false;
1123 	}
1124 
1125 	if ((opts->mask & NVMF_OPT_HOST_IFACE) &&
1126 	    (ctrl->opts->mask & NVMF_OPT_HOST_IFACE)) {
1127 		if (strcmp(opts->host_iface, ctrl->opts->host_iface))
1128 			return false;
1129 	} else if ((opts->mask & NVMF_OPT_HOST_IFACE) ||
1130 		   (ctrl->opts->mask & NVMF_OPT_HOST_IFACE)) {
1131 		return false;
1132 	}
1133 
1134 	return true;
1135 }
1136 EXPORT_SYMBOL_GPL(nvmf_ip_options_match);
1137 
1138 static int nvmf_check_allowed_opts(struct nvmf_ctrl_options *opts,
1139 		unsigned int allowed_opts)
1140 {
1141 	if (opts->mask & ~allowed_opts) {
1142 		unsigned int i;
1143 
1144 		for (i = 0; i < ARRAY_SIZE(opt_tokens); i++) {
1145 			if ((opt_tokens[i].token & opts->mask) &&
1146 			    (opt_tokens[i].token & ~allowed_opts)) {
1147 				pr_warn("invalid parameter '%s'\n",
1148 					opt_tokens[i].pattern);
1149 			}
1150 		}
1151 
1152 		return -EINVAL;
1153 	}
1154 
1155 	return 0;
1156 }
1157 
1158 void nvmf_free_options(struct nvmf_ctrl_options *opts)
1159 {
1160 	nvmf_host_put(opts->host);
1161 	kfree(opts->transport);
1162 	kfree(opts->traddr);
1163 	kfree(opts->trsvcid);
1164 	kfree(opts->subsysnqn);
1165 	kfree(opts->host_traddr);
1166 	kfree(opts->host_iface);
1167 	kfree(opts->dhchap_secret);
1168 	kfree(opts->dhchap_ctrl_secret);
1169 	kfree(opts);
1170 }
1171 EXPORT_SYMBOL_GPL(nvmf_free_options);
1172 
1173 #define NVMF_REQUIRED_OPTS	(NVMF_OPT_TRANSPORT | NVMF_OPT_NQN)
1174 #define NVMF_ALLOWED_OPTS	(NVMF_OPT_QUEUE_SIZE | NVMF_OPT_NR_IO_QUEUES | \
1175 				 NVMF_OPT_KATO | NVMF_OPT_HOSTNQN | \
1176 				 NVMF_OPT_HOST_ID | NVMF_OPT_DUP_CONNECT |\
1177 				 NVMF_OPT_DISABLE_SQFLOW | NVMF_OPT_DISCOVERY |\
1178 				 NVMF_OPT_FAIL_FAST_TMO | NVMF_OPT_DHCHAP_SECRET |\
1179 				 NVMF_OPT_DHCHAP_CTRL_SECRET)
1180 
1181 static struct nvme_ctrl *
1182 nvmf_create_ctrl(struct device *dev, const char *buf)
1183 {
1184 	struct nvmf_ctrl_options *opts;
1185 	struct nvmf_transport_ops *ops;
1186 	struct nvme_ctrl *ctrl;
1187 	int ret;
1188 
1189 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1190 	if (!opts)
1191 		return ERR_PTR(-ENOMEM);
1192 
1193 	ret = nvmf_parse_options(opts, buf);
1194 	if (ret)
1195 		goto out_free_opts;
1196 
1197 
1198 	request_module("nvme-%s", opts->transport);
1199 
1200 	/*
1201 	 * Check the generic options first as we need a valid transport for
1202 	 * the lookup below.  Then clear the generic flags so that transport
1203 	 * drivers don't have to care about them.
1204 	 */
1205 	ret = nvmf_check_required_opts(opts, NVMF_REQUIRED_OPTS);
1206 	if (ret)
1207 		goto out_free_opts;
1208 	opts->mask &= ~NVMF_REQUIRED_OPTS;
1209 
1210 	down_read(&nvmf_transports_rwsem);
1211 	ops = nvmf_lookup_transport(opts);
1212 	if (!ops) {
1213 		pr_info("no handler found for transport %s.\n",
1214 			opts->transport);
1215 		ret = -EINVAL;
1216 		goto out_unlock;
1217 	}
1218 
1219 	if (!try_module_get(ops->module)) {
1220 		ret = -EBUSY;
1221 		goto out_unlock;
1222 	}
1223 	up_read(&nvmf_transports_rwsem);
1224 
1225 	ret = nvmf_check_required_opts(opts, ops->required_opts);
1226 	if (ret)
1227 		goto out_module_put;
1228 	ret = nvmf_check_allowed_opts(opts, NVMF_ALLOWED_OPTS |
1229 				ops->allowed_opts | ops->required_opts);
1230 	if (ret)
1231 		goto out_module_put;
1232 
1233 	ctrl = ops->create_ctrl(dev, opts);
1234 	if (IS_ERR(ctrl)) {
1235 		ret = PTR_ERR(ctrl);
1236 		goto out_module_put;
1237 	}
1238 
1239 	module_put(ops->module);
1240 	return ctrl;
1241 
1242 out_module_put:
1243 	module_put(ops->module);
1244 	goto out_free_opts;
1245 out_unlock:
1246 	up_read(&nvmf_transports_rwsem);
1247 out_free_opts:
1248 	nvmf_free_options(opts);
1249 	return ERR_PTR(ret);
1250 }
1251 
1252 static struct class *nvmf_class;
1253 static struct device *nvmf_device;
1254 static DEFINE_MUTEX(nvmf_dev_mutex);
1255 
1256 static ssize_t nvmf_dev_write(struct file *file, const char __user *ubuf,
1257 		size_t count, loff_t *pos)
1258 {
1259 	struct seq_file *seq_file = file->private_data;
1260 	struct nvme_ctrl *ctrl;
1261 	const char *buf;
1262 	int ret = 0;
1263 
1264 	if (count > PAGE_SIZE)
1265 		return -ENOMEM;
1266 
1267 	buf = memdup_user_nul(ubuf, count);
1268 	if (IS_ERR(buf))
1269 		return PTR_ERR(buf);
1270 
1271 	mutex_lock(&nvmf_dev_mutex);
1272 	if (seq_file->private) {
1273 		ret = -EINVAL;
1274 		goto out_unlock;
1275 	}
1276 
1277 	ctrl = nvmf_create_ctrl(nvmf_device, buf);
1278 	if (IS_ERR(ctrl)) {
1279 		ret = PTR_ERR(ctrl);
1280 		goto out_unlock;
1281 	}
1282 
1283 	seq_file->private = ctrl;
1284 
1285 out_unlock:
1286 	mutex_unlock(&nvmf_dev_mutex);
1287 	kfree(buf);
1288 	return ret ? ret : count;
1289 }
1290 
1291 static void __nvmf_concat_opt_tokens(struct seq_file *seq_file)
1292 {
1293 	const struct match_token *tok;
1294 	int idx;
1295 
1296 	/*
1297 	 * Add dummy entries for instance and cntlid to
1298 	 * signal an invalid/non-existing controller
1299 	 */
1300 	seq_puts(seq_file, "instance=-1,cntlid=-1");
1301 	for (idx = 0; idx < ARRAY_SIZE(opt_tokens); idx++) {
1302 		tok = &opt_tokens[idx];
1303 		if (tok->token == NVMF_OPT_ERR)
1304 			continue;
1305 		seq_puts(seq_file, ",");
1306 		seq_puts(seq_file, tok->pattern);
1307 	}
1308 	seq_puts(seq_file, "\n");
1309 }
1310 
1311 static int nvmf_dev_show(struct seq_file *seq_file, void *private)
1312 {
1313 	struct nvme_ctrl *ctrl;
1314 
1315 	mutex_lock(&nvmf_dev_mutex);
1316 	ctrl = seq_file->private;
1317 	if (!ctrl) {
1318 		__nvmf_concat_opt_tokens(seq_file);
1319 		goto out_unlock;
1320 	}
1321 
1322 	seq_printf(seq_file, "instance=%d,cntlid=%d\n",
1323 			ctrl->instance, ctrl->cntlid);
1324 
1325 out_unlock:
1326 	mutex_unlock(&nvmf_dev_mutex);
1327 	return 0;
1328 }
1329 
1330 static int nvmf_dev_open(struct inode *inode, struct file *file)
1331 {
1332 	/*
1333 	 * The miscdevice code initializes file->private_data, but doesn't
1334 	 * make use of it later.
1335 	 */
1336 	file->private_data = NULL;
1337 	return single_open(file, nvmf_dev_show, NULL);
1338 }
1339 
1340 static int nvmf_dev_release(struct inode *inode, struct file *file)
1341 {
1342 	struct seq_file *seq_file = file->private_data;
1343 	struct nvme_ctrl *ctrl = seq_file->private;
1344 
1345 	if (ctrl)
1346 		nvme_put_ctrl(ctrl);
1347 	return single_release(inode, file);
1348 }
1349 
1350 static const struct file_operations nvmf_dev_fops = {
1351 	.owner		= THIS_MODULE,
1352 	.write		= nvmf_dev_write,
1353 	.read		= seq_read,
1354 	.open		= nvmf_dev_open,
1355 	.release	= nvmf_dev_release,
1356 };
1357 
1358 static struct miscdevice nvmf_misc = {
1359 	.minor		= MISC_DYNAMIC_MINOR,
1360 	.name           = "nvme-fabrics",
1361 	.fops		= &nvmf_dev_fops,
1362 };
1363 
1364 static int __init nvmf_init(void)
1365 {
1366 	int ret;
1367 
1368 	nvmf_default_host = nvmf_host_default();
1369 	if (!nvmf_default_host)
1370 		return -ENOMEM;
1371 
1372 	nvmf_class = class_create("nvme-fabrics");
1373 	if (IS_ERR(nvmf_class)) {
1374 		pr_err("couldn't register class nvme-fabrics\n");
1375 		ret = PTR_ERR(nvmf_class);
1376 		goto out_free_host;
1377 	}
1378 
1379 	nvmf_device =
1380 		device_create(nvmf_class, NULL, MKDEV(0, 0), NULL, "ctl");
1381 	if (IS_ERR(nvmf_device)) {
1382 		pr_err("couldn't create nvme-fabrics device!\n");
1383 		ret = PTR_ERR(nvmf_device);
1384 		goto out_destroy_class;
1385 	}
1386 
1387 	ret = misc_register(&nvmf_misc);
1388 	if (ret) {
1389 		pr_err("couldn't register misc device: %d\n", ret);
1390 		goto out_destroy_device;
1391 	}
1392 
1393 	return 0;
1394 
1395 out_destroy_device:
1396 	device_destroy(nvmf_class, MKDEV(0, 0));
1397 out_destroy_class:
1398 	class_destroy(nvmf_class);
1399 out_free_host:
1400 	nvmf_host_put(nvmf_default_host);
1401 	return ret;
1402 }
1403 
1404 static void __exit nvmf_exit(void)
1405 {
1406 	misc_deregister(&nvmf_misc);
1407 	device_destroy(nvmf_class, MKDEV(0, 0));
1408 	class_destroy(nvmf_class);
1409 	nvmf_host_put(nvmf_default_host);
1410 
1411 	BUILD_BUG_ON(sizeof(struct nvmf_common_command) != 64);
1412 	BUILD_BUG_ON(sizeof(struct nvmf_connect_command) != 64);
1413 	BUILD_BUG_ON(sizeof(struct nvmf_property_get_command) != 64);
1414 	BUILD_BUG_ON(sizeof(struct nvmf_property_set_command) != 64);
1415 	BUILD_BUG_ON(sizeof(struct nvmf_auth_send_command) != 64);
1416 	BUILD_BUG_ON(sizeof(struct nvmf_auth_receive_command) != 64);
1417 	BUILD_BUG_ON(sizeof(struct nvmf_connect_data) != 1024);
1418 	BUILD_BUG_ON(sizeof(struct nvmf_auth_dhchap_negotiate_data) != 8);
1419 	BUILD_BUG_ON(sizeof(struct nvmf_auth_dhchap_challenge_data) != 16);
1420 	BUILD_BUG_ON(sizeof(struct nvmf_auth_dhchap_reply_data) != 16);
1421 	BUILD_BUG_ON(sizeof(struct nvmf_auth_dhchap_success1_data) != 16);
1422 	BUILD_BUG_ON(sizeof(struct nvmf_auth_dhchap_success2_data) != 16);
1423 }
1424 
1425 MODULE_LICENSE("GPL v2");
1426 
1427 module_init(nvmf_init);
1428 module_exit(nvmf_exit);
1429