xref: /spdk/lib/nvmf/nvmf.c (revision 6b6dfea6c704a049e553024aa7e44ae916948e20)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2018-2019 Mellanox Technologies LTD. All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "spdk/stdinc.h"
35 
36 #include "spdk/bdev.h"
37 #include "spdk/bit_array.h"
38 #include "spdk/conf.h"
39 #include "spdk/thread.h"
40 #include "spdk/nvmf.h"
41 #include "spdk/trace.h"
42 #include "spdk/endian.h"
43 #include "spdk/string.h"
44 
45 #include "spdk_internal/log.h"
46 
47 #include "nvmf_internal.h"
48 #include "transport.h"
49 
50 SPDK_LOG_REGISTER_COMPONENT("nvmf", SPDK_LOG_NVMF)
51 
52 #define SPDK_NVMF_DEFAULT_MAX_SUBSYSTEMS 1024
53 
54 static TAILQ_HEAD(, spdk_nvmf_tgt) g_nvmf_tgts = TAILQ_HEAD_INITIALIZER(g_nvmf_tgts);
55 
56 typedef void (*nvmf_qpair_disconnect_cpl)(void *ctx, int status);
57 static void spdk_nvmf_tgt_destroy_poll_group(void *io_device, void *ctx_buf);
58 
59 /* supplied to a single call to nvmf_qpair_disconnect */
60 struct nvmf_qpair_disconnect_ctx {
61 	struct spdk_nvmf_qpair *qpair;
62 	struct spdk_nvmf_ctrlr *ctrlr;
63 	nvmf_qpair_disconnect_cb cb_fn;
64 	struct spdk_thread *thread;
65 	void *ctx;
66 	uint16_t qid;
67 };
68 
69 /*
70  * There are several times when we need to iterate through the list of all qpairs and selectively delete them.
71  * In order to do this sequentially without overlap, we must provide a context to recover the next qpair from
72  * to enable calling nvmf_qpair_disconnect on the next desired qpair.
73  */
74 struct nvmf_qpair_disconnect_many_ctx {
75 	struct spdk_nvmf_subsystem *subsystem;
76 	struct spdk_nvmf_poll_group *group;
77 	spdk_nvmf_poll_group_mod_done cpl_fn;
78 	void *cpl_ctx;
79 };
80 
81 static void
82 spdk_nvmf_qpair_set_state(struct spdk_nvmf_qpair *qpair,
83 			  enum spdk_nvmf_qpair_state state)
84 {
85 	assert(qpair != NULL);
86 	assert(qpair->group->thread == spdk_get_thread());
87 
88 	qpair->state = state;
89 }
90 
91 static int
92 spdk_nvmf_poll_group_poll(void *ctx)
93 {
94 	struct spdk_nvmf_poll_group *group = ctx;
95 	int rc;
96 	int count = 0;
97 	struct spdk_nvmf_transport_poll_group *tgroup;
98 
99 	TAILQ_FOREACH(tgroup, &group->tgroups, link) {
100 		rc = spdk_nvmf_transport_poll_group_poll(tgroup);
101 		if (rc < 0) {
102 			return -1;
103 		}
104 		count += rc;
105 	}
106 
107 	return count;
108 }
109 
110 static int
111 spdk_nvmf_tgt_create_poll_group(void *io_device, void *ctx_buf)
112 {
113 	struct spdk_nvmf_tgt *tgt = io_device;
114 	struct spdk_nvmf_poll_group *group = ctx_buf;
115 	struct spdk_nvmf_transport *transport;
116 	uint32_t sid;
117 
118 	TAILQ_INIT(&group->tgroups);
119 	TAILQ_INIT(&group->qpairs);
120 
121 	TAILQ_FOREACH(transport, &tgt->transports, link) {
122 		spdk_nvmf_poll_group_add_transport(group, transport);
123 	}
124 
125 	group->num_sgroups = tgt->max_subsystems;
126 	group->sgroups = calloc(tgt->max_subsystems, sizeof(struct spdk_nvmf_subsystem_poll_group));
127 	if (!group->sgroups) {
128 		return -ENOMEM;
129 	}
130 
131 	for (sid = 0; sid < tgt->max_subsystems; sid++) {
132 		struct spdk_nvmf_subsystem *subsystem;
133 
134 		subsystem = tgt->subsystems[sid];
135 		if (!subsystem) {
136 			continue;
137 		}
138 
139 		if (spdk_nvmf_poll_group_add_subsystem(group, subsystem, NULL, NULL) != 0) {
140 			spdk_nvmf_tgt_destroy_poll_group(io_device, ctx_buf);
141 			return -1;
142 		}
143 	}
144 
145 	group->poller = spdk_poller_register(spdk_nvmf_poll_group_poll, group, 0);
146 	group->thread = spdk_get_thread();
147 
148 	return 0;
149 }
150 
151 static void
152 spdk_nvmf_tgt_destroy_poll_group(void *io_device, void *ctx_buf)
153 {
154 	struct spdk_nvmf_poll_group *group = ctx_buf;
155 	struct spdk_nvmf_transport_poll_group *tgroup, *tmp;
156 	struct spdk_nvmf_subsystem_poll_group *sgroup;
157 	uint32_t sid, nsid;
158 
159 	TAILQ_FOREACH_SAFE(tgroup, &group->tgroups, link, tmp) {
160 		TAILQ_REMOVE(&group->tgroups, tgroup, link);
161 		spdk_nvmf_transport_poll_group_destroy(tgroup);
162 	}
163 
164 	for (sid = 0; sid < group->num_sgroups; sid++) {
165 		sgroup = &group->sgroups[sid];
166 
167 		for (nsid = 0; nsid < sgroup->num_ns; nsid++) {
168 			if (sgroup->ns_info[nsid].channel) {
169 				spdk_put_io_channel(sgroup->ns_info[nsid].channel);
170 				sgroup->ns_info[nsid].channel = NULL;
171 			}
172 		}
173 
174 		free(sgroup->ns_info);
175 	}
176 
177 	free(group->sgroups);
178 }
179 
180 static void
181 _nvmf_tgt_disconnect_next_qpair(void *ctx)
182 {
183 	struct spdk_nvmf_qpair *qpair;
184 	struct nvmf_qpair_disconnect_many_ctx *qpair_ctx = ctx;
185 	struct spdk_nvmf_poll_group *group = qpair_ctx->group;
186 	struct spdk_io_channel *ch;
187 	int rc = 0;
188 
189 	qpair = TAILQ_FIRST(&group->qpairs);
190 
191 	if (qpair) {
192 		rc = spdk_nvmf_qpair_disconnect(qpair, _nvmf_tgt_disconnect_next_qpair, ctx);
193 	}
194 
195 	if (!qpair || rc != 0) {
196 		/* When the refcount from the channels reaches 0, spdk_nvmf_tgt_destroy_poll_group will be called. */
197 		ch = spdk_io_channel_from_ctx(group);
198 		spdk_put_io_channel(ch);
199 		free(qpair_ctx);
200 	}
201 }
202 
203 static void
204 spdk_nvmf_tgt_destroy_poll_group_qpairs(struct spdk_nvmf_poll_group *group)
205 {
206 	struct nvmf_qpair_disconnect_many_ctx *ctx;
207 
208 	ctx = calloc(1, sizeof(struct nvmf_qpair_disconnect_many_ctx));
209 
210 	if (!ctx) {
211 		SPDK_ERRLOG("Failed to allocate memory for destroy poll group ctx\n");
212 		return;
213 	}
214 
215 	spdk_poller_unregister(&group->poller);
216 
217 	ctx->group = group;
218 	_nvmf_tgt_disconnect_next_qpair(ctx);
219 }
220 
221 struct spdk_nvmf_tgt *
222 spdk_nvmf_tgt_create(struct spdk_nvmf_target_opts *opts)
223 {
224 	struct spdk_nvmf_tgt *tgt, *tmp_tgt;
225 
226 	if (strnlen(opts->name, NVMF_TGT_NAME_MAX_LENGTH) == NVMF_TGT_NAME_MAX_LENGTH) {
227 		SPDK_ERRLOG("Provided target name exceeds the max length of %u.\n", NVMF_TGT_NAME_MAX_LENGTH);
228 		return NULL;
229 	}
230 
231 	TAILQ_FOREACH(tmp_tgt, &g_nvmf_tgts, link) {
232 		if (!strncmp(opts->name, tmp_tgt->name, strlen(tmp_tgt->name))) {
233 			SPDK_ERRLOG("Provided target name must be unique.\n");
234 			return NULL;
235 		}
236 	}
237 
238 	tgt = calloc(1, sizeof(*tgt));
239 	if (!tgt) {
240 		return NULL;
241 	}
242 
243 	snprintf(tgt->name, NVMF_TGT_NAME_MAX_LENGTH, "%s", opts->name);
244 
245 	if (!opts || !opts->max_subsystems) {
246 		tgt->max_subsystems = SPDK_NVMF_DEFAULT_MAX_SUBSYSTEMS;
247 	} else {
248 		tgt->max_subsystems = opts->max_subsystems;
249 	}
250 
251 	tgt->discovery_genctr = 0;
252 	TAILQ_INIT(&tgt->transports);
253 
254 	tgt->subsystems = calloc(tgt->max_subsystems, sizeof(struct spdk_nvmf_subsystem *));
255 	if (!tgt->subsystems) {
256 		free(tgt);
257 		return NULL;
258 	}
259 
260 	TAILQ_INSERT_HEAD(&g_nvmf_tgts, tgt, link);
261 
262 	spdk_io_device_register(tgt,
263 				spdk_nvmf_tgt_create_poll_group,
264 				spdk_nvmf_tgt_destroy_poll_group,
265 				sizeof(struct spdk_nvmf_poll_group),
266 				tgt->name);
267 
268 	return tgt;
269 }
270 
271 static void
272 spdk_nvmf_tgt_destroy_cb(void *io_device)
273 {
274 	struct spdk_nvmf_tgt *tgt = io_device;
275 	struct spdk_nvmf_transport *transport, *transport_tmp;
276 	spdk_nvmf_tgt_destroy_done_fn		*destroy_cb_fn;
277 	void					*destroy_cb_arg;
278 	uint32_t i;
279 
280 	if (tgt->subsystems) {
281 		for (i = 0; i < tgt->max_subsystems; i++) {
282 			if (tgt->subsystems[i]) {
283 				spdk_nvmf_subsystem_destroy(tgt->subsystems[i]);
284 			}
285 		}
286 		free(tgt->subsystems);
287 	}
288 
289 	TAILQ_FOREACH_SAFE(transport, &tgt->transports, link, transport_tmp) {
290 		TAILQ_REMOVE(&tgt->transports, transport, link);
291 		spdk_nvmf_transport_destroy(transport);
292 	}
293 
294 	destroy_cb_fn = tgt->destroy_cb_fn;
295 	destroy_cb_arg = tgt->destroy_cb_arg;
296 
297 	free(tgt);
298 
299 	if (destroy_cb_fn) {
300 		destroy_cb_fn(destroy_cb_arg, 0);
301 	}
302 }
303 
304 void
305 spdk_nvmf_tgt_destroy(struct spdk_nvmf_tgt *tgt,
306 		      spdk_nvmf_tgt_destroy_done_fn cb_fn,
307 		      void *cb_arg)
308 {
309 	tgt->destroy_cb_fn = cb_fn;
310 	tgt->destroy_cb_arg = cb_arg;
311 
312 	TAILQ_REMOVE(&g_nvmf_tgts, tgt, link);
313 
314 	spdk_io_device_unregister(tgt, spdk_nvmf_tgt_destroy_cb);
315 }
316 
317 const char *
318 spdk_nvmf_tgt_get_name(struct spdk_nvmf_tgt *tgt)
319 {
320 	return tgt->name;
321 }
322 
323 struct spdk_nvmf_tgt *
324 spdk_nvmf_get_tgt(const char *name)
325 {
326 	struct spdk_nvmf_tgt *tgt;
327 	uint32_t num_targets = 0;
328 
329 	TAILQ_FOREACH(tgt, &g_nvmf_tgts, link) {
330 		if (name) {
331 			if (!strncmp(tgt->name, name, strlen(tgt->name))) {
332 				return tgt;
333 			}
334 		}
335 		num_targets++;
336 	}
337 
338 	/*
339 	 * special case. If there is only one target and
340 	 * no name was specified, return the only available
341 	 * target. If there is more than one target, name must
342 	 * be specified.
343 	 */
344 	if (!name && num_targets == 1) {
345 		return TAILQ_FIRST(&g_nvmf_tgts);
346 	}
347 
348 	return NULL;
349 }
350 
351 struct spdk_nvmf_tgt *
352 spdk_nvmf_get_first_tgt(void)
353 {
354 	return TAILQ_FIRST(&g_nvmf_tgts);
355 }
356 
357 struct spdk_nvmf_tgt *
358 spdk_nvmf_get_next_tgt(struct spdk_nvmf_tgt *prev)
359 {
360 	return TAILQ_NEXT(prev, link);
361 }
362 
363 static void
364 spdk_nvmf_write_subsystem_config_json(struct spdk_json_write_ctx *w,
365 				      struct spdk_nvmf_subsystem *subsystem)
366 {
367 	struct spdk_nvmf_host *host;
368 	struct spdk_nvmf_listener *listener;
369 	const struct spdk_nvme_transport_id *trid;
370 	struct spdk_nvmf_ns *ns;
371 	struct spdk_nvmf_ns_opts ns_opts;
372 	uint32_t max_namespaces;
373 	char uuid_str[SPDK_UUID_STRING_LEN];
374 	const char *trtype;
375 	const char *adrfam;
376 
377 	if (spdk_nvmf_subsystem_get_type(subsystem) != SPDK_NVMF_SUBTYPE_NVME) {
378 		return;
379 	}
380 
381 	/* { */
382 	spdk_json_write_object_begin(w);
383 	spdk_json_write_named_string(w, "method", "nvmf_create_subsystem");
384 
385 	/*     "params" : { */
386 	spdk_json_write_named_object_begin(w, "params");
387 	spdk_json_write_named_string(w, "nqn", spdk_nvmf_subsystem_get_nqn(subsystem));
388 	spdk_json_write_named_bool(w, "allow_any_host", spdk_nvmf_subsystem_get_allow_any_host(subsystem));
389 	spdk_json_write_named_string(w, "serial_number", spdk_nvmf_subsystem_get_sn(subsystem));
390 	spdk_json_write_named_string(w, "model_number", spdk_nvmf_subsystem_get_mn(subsystem));
391 
392 	max_namespaces = spdk_nvmf_subsystem_get_max_namespaces(subsystem);
393 	if (max_namespaces != 0) {
394 		spdk_json_write_named_uint32(w, "max_namespaces", max_namespaces);
395 	}
396 
397 	/*     } "params" */
398 	spdk_json_write_object_end(w);
399 
400 	/* } */
401 	spdk_json_write_object_end(w);
402 
403 	for (listener = spdk_nvmf_subsystem_get_first_listener(subsystem); listener != NULL;
404 	     listener = spdk_nvmf_subsystem_get_next_listener(subsystem, listener)) {
405 		trid = spdk_nvmf_listener_get_trid(listener);
406 
407 		trtype = spdk_nvme_transport_id_trtype_str(trid->trtype);
408 		adrfam = spdk_nvme_transport_id_adrfam_str(trid->adrfam);
409 
410 		spdk_json_write_object_begin(w);
411 		spdk_json_write_named_string(w, "method", "nvmf_subsystem_add_listener");
412 
413 		/*     "params" : { */
414 		spdk_json_write_named_object_begin(w, "params");
415 
416 		spdk_json_write_named_string(w, "nqn", spdk_nvmf_subsystem_get_nqn(subsystem));
417 
418 		/*     "listen_address" : { */
419 		spdk_json_write_named_object_begin(w, "listen_address");
420 
421 		spdk_json_write_named_string(w, "trtype", trtype);
422 		if (adrfam) {
423 			spdk_json_write_named_string(w, "adrfam", adrfam);
424 		}
425 
426 		spdk_json_write_named_string(w, "traddr", trid->traddr);
427 		spdk_json_write_named_string(w, "trsvcid", trid->trsvcid);
428 		/*     } "listen_address" */
429 		spdk_json_write_object_end(w);
430 
431 		/*     } "params" */
432 		spdk_json_write_object_end(w);
433 
434 		/* } */
435 		spdk_json_write_object_end(w);
436 	}
437 
438 	for (host = spdk_nvmf_subsystem_get_first_host(subsystem); host != NULL;
439 	     host = spdk_nvmf_subsystem_get_next_host(subsystem, host)) {
440 
441 		spdk_json_write_object_begin(w);
442 		spdk_json_write_named_string(w, "method", "nvmf_subsystem_add_host");
443 
444 		/*     "params" : { */
445 		spdk_json_write_named_object_begin(w, "params");
446 
447 		spdk_json_write_named_string(w, "nqn", spdk_nvmf_subsystem_get_nqn(subsystem));
448 		spdk_json_write_named_string(w, "host", spdk_nvmf_host_get_nqn(host));
449 
450 		/*     } "params" */
451 		spdk_json_write_object_end(w);
452 
453 		/* } */
454 		spdk_json_write_object_end(w);
455 	}
456 
457 	for (ns = spdk_nvmf_subsystem_get_first_ns(subsystem); ns != NULL;
458 	     ns = spdk_nvmf_subsystem_get_next_ns(subsystem, ns)) {
459 		spdk_nvmf_ns_get_opts(ns, &ns_opts, sizeof(ns_opts));
460 
461 		spdk_json_write_object_begin(w);
462 		spdk_json_write_named_string(w, "method", "nvmf_subsystem_add_ns");
463 
464 		/*     "params" : { */
465 		spdk_json_write_named_object_begin(w, "params");
466 
467 		spdk_json_write_named_string(w, "nqn", spdk_nvmf_subsystem_get_nqn(subsystem));
468 
469 		/*     "namespace" : { */
470 		spdk_json_write_named_object_begin(w, "namespace");
471 
472 		spdk_json_write_named_uint32(w, "nsid", spdk_nvmf_ns_get_id(ns));
473 		spdk_json_write_named_string(w, "bdev_name", spdk_bdev_get_name(spdk_nvmf_ns_get_bdev(ns)));
474 
475 		if (!spdk_mem_all_zero(ns_opts.nguid, sizeof(ns_opts.nguid))) {
476 			SPDK_STATIC_ASSERT(sizeof(ns_opts.nguid) == sizeof(uint64_t) * 2, "size mismatch");
477 			spdk_json_write_named_string_fmt(w, "nguid", "%016"PRIX64"%016"PRIX64, from_be64(&ns_opts.nguid[0]),
478 							 from_be64(&ns_opts.nguid[8]));
479 		}
480 
481 		if (!spdk_mem_all_zero(ns_opts.eui64, sizeof(ns_opts.eui64))) {
482 			SPDK_STATIC_ASSERT(sizeof(ns_opts.eui64) == sizeof(uint64_t), "size mismatch");
483 			spdk_json_write_named_string_fmt(w, "eui64", "%016"PRIX64, from_be64(&ns_opts.eui64));
484 		}
485 
486 		if (!spdk_mem_all_zero(&ns_opts.uuid, sizeof(ns_opts.uuid))) {
487 			spdk_uuid_fmt_lower(uuid_str, sizeof(uuid_str), &ns_opts.uuid);
488 			spdk_json_write_named_string(w, "uuid",  uuid_str);
489 		}
490 
491 		/*     "namespace" */
492 		spdk_json_write_object_end(w);
493 
494 		/*     } "params" */
495 		spdk_json_write_object_end(w);
496 
497 		/* } */
498 		spdk_json_write_object_end(w);
499 	}
500 }
501 
502 void
503 spdk_nvmf_tgt_write_config_json(struct spdk_json_write_ctx *w, struct spdk_nvmf_tgt *tgt)
504 {
505 	struct spdk_nvmf_subsystem *subsystem;
506 	struct spdk_nvmf_transport *transport;
507 
508 	spdk_json_write_object_begin(w);
509 	spdk_json_write_named_string(w, "method", "nvmf_set_max_subsystems");
510 
511 	spdk_json_write_named_object_begin(w, "params");
512 	spdk_json_write_named_uint32(w, "max_subsystems", tgt->max_subsystems);
513 	spdk_json_write_object_end(w);
514 
515 	spdk_json_write_object_end(w);
516 
517 	/* write transports */
518 	TAILQ_FOREACH(transport, &tgt->transports, link) {
519 		spdk_json_write_object_begin(w);
520 		spdk_json_write_named_string(w, "method", "nvmf_create_transport");
521 
522 		spdk_json_write_named_object_begin(w, "params");
523 		spdk_json_write_named_string(w, "trtype", spdk_nvme_transport_id_trtype_str(transport->ops->type));
524 		spdk_json_write_named_uint32(w, "max_queue_depth", transport->opts.max_queue_depth);
525 		spdk_json_write_named_uint32(w, "max_qpairs_per_ctrlr", transport->opts.max_qpairs_per_ctrlr);
526 		spdk_json_write_named_uint32(w, "in_capsule_data_size", transport->opts.in_capsule_data_size);
527 		spdk_json_write_named_uint32(w, "max_io_size", transport->opts.max_io_size);
528 		spdk_json_write_named_uint32(w, "io_unit_size", transport->opts.io_unit_size);
529 		spdk_json_write_named_uint32(w, "max_aq_depth", transport->opts.max_aq_depth);
530 		if (transport->ops->type == SPDK_NVME_TRANSPORT_RDMA) {
531 			spdk_json_write_named_uint32(w, "max_srq_depth", transport->opts.max_srq_depth);
532 		}
533 		spdk_json_write_object_end(w);
534 
535 		spdk_json_write_object_end(w);
536 	}
537 
538 	subsystem = spdk_nvmf_subsystem_get_first(tgt);
539 	while (subsystem) {
540 		spdk_nvmf_write_subsystem_config_json(w, subsystem);
541 		subsystem = spdk_nvmf_subsystem_get_next(subsystem);
542 	}
543 }
544 
545 void
546 spdk_nvmf_tgt_listen(struct spdk_nvmf_tgt *tgt,
547 		     struct spdk_nvme_transport_id *trid,
548 		     spdk_nvmf_tgt_listen_done_fn cb_fn,
549 		     void *cb_arg)
550 {
551 	struct spdk_nvmf_transport *transport;
552 	const char *trtype;
553 	int rc;
554 
555 	transport = spdk_nvmf_tgt_get_transport(tgt, trid->trtype);
556 	if (!transport) {
557 		trtype = spdk_nvme_transport_id_trtype_str(trid->trtype);
558 		if (trtype != NULL) {
559 			SPDK_ERRLOG("Unable to listen on transport %s. The transport must be created first.\n", trtype);
560 		} else {
561 			SPDK_ERRLOG("The specified trtype %d is unknown. Please make sure that it is properly registered.\n",
562 				    trid->trtype);
563 		}
564 		cb_fn(cb_arg, -EINVAL);
565 		return;
566 	}
567 
568 	rc = spdk_nvmf_transport_listen(transport, trid);
569 	if (rc < 0) {
570 		SPDK_ERRLOG("Unable to listen on address '%s'\n", trid->traddr);
571 		cb_fn(cb_arg, rc);
572 		return;
573 	}
574 
575 	tgt->discovery_genctr++;
576 
577 	cb_fn(cb_arg, 0);
578 }
579 
580 struct spdk_nvmf_tgt_add_transport_ctx {
581 	struct spdk_nvmf_tgt *tgt;
582 	struct spdk_nvmf_transport *transport;
583 	spdk_nvmf_tgt_add_transport_done_fn cb_fn;
584 	void *cb_arg;
585 };
586 
587 static void
588 _spdk_nvmf_tgt_add_transport_done(struct spdk_io_channel_iter *i, int status)
589 {
590 	struct spdk_nvmf_tgt_add_transport_ctx *ctx = spdk_io_channel_iter_get_ctx(i);
591 
592 	ctx->cb_fn(ctx->cb_arg, status);
593 
594 	free(ctx);
595 }
596 
597 static void
598 _spdk_nvmf_tgt_add_transport(struct spdk_io_channel_iter *i)
599 {
600 	struct spdk_nvmf_tgt_add_transport_ctx *ctx = spdk_io_channel_iter_get_ctx(i);
601 	struct spdk_io_channel *ch = spdk_io_channel_iter_get_channel(i);
602 	struct spdk_nvmf_poll_group *group = spdk_io_channel_get_ctx(ch);
603 	int rc;
604 
605 	rc = spdk_nvmf_poll_group_add_transport(group, ctx->transport);
606 	spdk_for_each_channel_continue(i, rc);
607 }
608 
609 void spdk_nvmf_tgt_add_transport(struct spdk_nvmf_tgt *tgt,
610 				 struct spdk_nvmf_transport *transport,
611 				 spdk_nvmf_tgt_add_transport_done_fn cb_fn,
612 				 void *cb_arg)
613 {
614 	struct spdk_nvmf_tgt_add_transport_ctx *ctx;
615 
616 	if (spdk_nvmf_tgt_get_transport(tgt, transport->ops->type)) {
617 		cb_fn(cb_arg, -EEXIST);
618 		return; /* transport already created */
619 	}
620 
621 	transport->tgt = tgt;
622 	TAILQ_INSERT_TAIL(&tgt->transports, transport, link);
623 
624 	ctx = calloc(1, sizeof(*ctx));
625 	if (!ctx) {
626 		cb_fn(cb_arg, -ENOMEM);
627 		return;
628 	}
629 
630 	ctx->tgt = tgt;
631 	ctx->transport = transport;
632 	ctx->cb_fn = cb_fn;
633 	ctx->cb_arg = cb_arg;
634 
635 	spdk_for_each_channel(tgt,
636 			      _spdk_nvmf_tgt_add_transport,
637 			      ctx,
638 			      _spdk_nvmf_tgt_add_transport_done);
639 }
640 
641 struct spdk_nvmf_subsystem *
642 spdk_nvmf_tgt_find_subsystem(struct spdk_nvmf_tgt *tgt, const char *subnqn)
643 {
644 	struct spdk_nvmf_subsystem	*subsystem;
645 	uint32_t sid;
646 
647 	if (!subnqn) {
648 		return NULL;
649 	}
650 
651 	for (sid = 0; sid < tgt->max_subsystems; sid++) {
652 		subsystem = tgt->subsystems[sid];
653 		if (subsystem == NULL) {
654 			continue;
655 		}
656 
657 		if (strcmp(subnqn, subsystem->subnqn) == 0) {
658 			return subsystem;
659 		}
660 	}
661 
662 	return NULL;
663 }
664 
665 struct spdk_nvmf_transport *
666 spdk_nvmf_tgt_get_transport(struct spdk_nvmf_tgt *tgt, enum spdk_nvme_transport_type type)
667 {
668 	struct spdk_nvmf_transport *transport;
669 
670 	TAILQ_FOREACH(transport, &tgt->transports, link) {
671 		if (transport->ops->type == type) {
672 			return transport;
673 		}
674 	}
675 
676 	return NULL;
677 }
678 
679 void
680 spdk_nvmf_tgt_accept(struct spdk_nvmf_tgt *tgt, new_qpair_fn cb_fn)
681 {
682 	struct spdk_nvmf_transport *transport, *tmp;
683 
684 	TAILQ_FOREACH_SAFE(transport, &tgt->transports, link, tmp) {
685 		spdk_nvmf_transport_accept(transport, cb_fn);
686 	}
687 }
688 
689 struct spdk_nvmf_poll_group *
690 spdk_nvmf_poll_group_create(struct spdk_nvmf_tgt *tgt)
691 {
692 	struct spdk_io_channel *ch;
693 
694 	ch = spdk_get_io_channel(tgt);
695 	if (!ch) {
696 		SPDK_ERRLOG("Unable to get I/O channel for target\n");
697 		return NULL;
698 	}
699 
700 	return spdk_io_channel_get_ctx(ch);
701 }
702 
703 void
704 spdk_nvmf_poll_group_destroy(struct spdk_nvmf_poll_group *group)
705 {
706 	/* This function will put the io_channel associated with this poll group */
707 	spdk_nvmf_tgt_destroy_poll_group_qpairs(group);
708 }
709 
710 int
711 spdk_nvmf_poll_group_add(struct spdk_nvmf_poll_group *group,
712 			 struct spdk_nvmf_qpair *qpair)
713 {
714 	int rc = -1;
715 	struct spdk_nvmf_transport_poll_group *tgroup;
716 
717 	TAILQ_INIT(&qpair->outstanding);
718 	qpair->group = group;
719 
720 	TAILQ_FOREACH(tgroup, &group->tgroups, link) {
721 		if (tgroup->transport == qpair->transport) {
722 			rc = spdk_nvmf_transport_poll_group_add(tgroup, qpair);
723 			break;
724 		}
725 	}
726 
727 	/* We add the qpair to the group only it is succesfully added into the tgroup */
728 	if (rc == 0) {
729 		TAILQ_INSERT_TAIL(&group->qpairs, qpair, link);
730 		spdk_nvmf_qpair_set_state(qpair, SPDK_NVMF_QPAIR_ACTIVE);
731 	}
732 
733 	return rc;
734 }
735 
736 static
737 void _nvmf_ctrlr_destruct(void *ctx)
738 {
739 	struct spdk_nvmf_ctrlr *ctrlr = ctx;
740 
741 	spdk_nvmf_ctrlr_destruct(ctrlr);
742 }
743 
744 static void
745 _spdk_nvmf_ctrlr_free_from_qpair(void *ctx)
746 {
747 	struct nvmf_qpair_disconnect_ctx *qpair_ctx = ctx;
748 	struct spdk_nvmf_ctrlr *ctrlr = qpair_ctx->ctrlr;
749 	uint32_t count;
750 
751 	spdk_bit_array_clear(ctrlr->qpair_mask, qpair_ctx->qid);
752 	count = spdk_bit_array_count_set(ctrlr->qpair_mask);
753 	if (count == 0) {
754 		spdk_bit_array_free(&ctrlr->qpair_mask);
755 
756 		spdk_thread_send_msg(ctrlr->subsys->thread, _nvmf_ctrlr_destruct, ctrlr);
757 	}
758 
759 	if (qpair_ctx->cb_fn) {
760 		spdk_thread_send_msg(qpair_ctx->thread, qpair_ctx->cb_fn, qpair_ctx->ctx);
761 	}
762 	free(qpair_ctx);
763 }
764 
765 static void
766 _spdk_nvmf_qpair_destroy(void *ctx, int status)
767 {
768 	struct nvmf_qpair_disconnect_ctx *qpair_ctx = ctx;
769 	struct spdk_nvmf_qpair *qpair = qpair_ctx->qpair;
770 	struct spdk_nvmf_ctrlr *ctrlr = qpair->ctrlr;
771 	struct spdk_nvmf_transport_poll_group *tgroup;
772 	struct spdk_nvmf_request *req, *tmp;
773 	struct spdk_nvmf_subsystem_poll_group *sgroup;
774 	int rc;
775 
776 	assert(qpair->state == SPDK_NVMF_QPAIR_DEACTIVATING);
777 	spdk_nvmf_qpair_set_state(qpair, SPDK_NVMF_QPAIR_ERROR);
778 	qpair_ctx->qid = qpair->qid;
779 
780 	/* Find the tgroup and remove the qpair from the tgroup */
781 	TAILQ_FOREACH(tgroup, &qpair->group->tgroups, link) {
782 		if (tgroup->transport == qpair->transport) {
783 			rc = spdk_nvmf_transport_poll_group_remove(tgroup, qpair);
784 			if (rc && (rc != ENOTSUP)) {
785 				SPDK_ERRLOG("Cannot remove qpair=%p from transport group=%p\n",
786 					    qpair, tgroup);
787 			}
788 			break;
789 		}
790 	}
791 
792 	if (ctrlr) {
793 		sgroup = &qpair->group->sgroups[ctrlr->subsys->id];
794 		TAILQ_FOREACH_SAFE(req, &sgroup->queued, link, tmp) {
795 			if (req->qpair == qpair) {
796 				TAILQ_REMOVE(&sgroup->queued, req, link);
797 				if (spdk_nvmf_transport_req_free(req)) {
798 					SPDK_ERRLOG("Transport request free error!\n");
799 				}
800 			}
801 		}
802 	}
803 
804 	TAILQ_REMOVE(&qpair->group->qpairs, qpair, link);
805 
806 	spdk_nvmf_transport_qpair_fini(qpair);
807 
808 	if (!ctrlr || !ctrlr->thread) {
809 		if (qpair_ctx->cb_fn) {
810 			spdk_thread_send_msg(qpair_ctx->thread, qpair_ctx->cb_fn, qpair_ctx->ctx);
811 		}
812 		free(qpair_ctx);
813 		return;
814 	}
815 
816 	qpair_ctx->ctrlr = ctrlr;
817 	spdk_thread_send_msg(ctrlr->thread, _spdk_nvmf_ctrlr_free_from_qpair, qpair_ctx);
818 
819 }
820 
821 int
822 spdk_nvmf_qpair_disconnect(struct spdk_nvmf_qpair *qpair, nvmf_qpair_disconnect_cb cb_fn, void *ctx)
823 {
824 	struct nvmf_qpair_disconnect_ctx *qpair_ctx;
825 
826 	/* If we get a qpair in the uninitialized state, we can just destroy it immediately */
827 	if (qpair->state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
828 		spdk_nvmf_transport_qpair_fini(qpair);
829 		if (cb_fn) {
830 			cb_fn(ctx);
831 		}
832 		return 0;
833 	}
834 
835 	/* The queue pair must be disconnected from the thread that owns it */
836 	assert(qpair->group->thread == spdk_get_thread());
837 
838 	if (qpair->state != SPDK_NVMF_QPAIR_ACTIVE) {
839 		/* This can occur if the connection is killed by the target,
840 		 * which results in a notification that the connection
841 		 * died. Send a message to defer the processing of this
842 		 * callback. This allows the stack to unwind in the case
843 		 * where a bunch of connections are disconnected in
844 		 * a loop. */
845 		if (cb_fn) {
846 			spdk_thread_send_msg(qpair->group->thread, cb_fn, ctx);
847 		}
848 		return 0;
849 	}
850 
851 	assert(qpair->state == SPDK_NVMF_QPAIR_ACTIVE);
852 	spdk_nvmf_qpair_set_state(qpair, SPDK_NVMF_QPAIR_DEACTIVATING);
853 
854 	qpair_ctx = calloc(1, sizeof(struct nvmf_qpair_disconnect_ctx));
855 	if (!qpair_ctx) {
856 		SPDK_ERRLOG("Unable to allocate context for nvmf_qpair_disconnect\n");
857 		return -ENOMEM;
858 	}
859 
860 	qpair_ctx->qpair = qpair;
861 	qpair_ctx->cb_fn = cb_fn;
862 	qpair_ctx->thread = qpair->group->thread;
863 	qpair_ctx->ctx = ctx;
864 
865 	/* Check for outstanding I/O */
866 	if (!TAILQ_EMPTY(&qpair->outstanding)) {
867 		qpair->state_cb = _spdk_nvmf_qpair_destroy;
868 		qpair->state_cb_arg = qpair_ctx;
869 		spdk_nvmf_qpair_free_aer(qpair);
870 		return 0;
871 	}
872 
873 	_spdk_nvmf_qpair_destroy(qpair_ctx, 0);
874 
875 	return 0;
876 }
877 
878 int
879 spdk_nvmf_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
880 			      struct spdk_nvme_transport_id *trid)
881 {
882 	return spdk_nvmf_transport_qpair_get_peer_trid(qpair, trid);
883 }
884 
885 int
886 spdk_nvmf_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
887 			       struct spdk_nvme_transport_id *trid)
888 {
889 	return spdk_nvmf_transport_qpair_get_local_trid(qpair, trid);
890 }
891 
892 int
893 spdk_nvmf_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
894 				struct spdk_nvme_transport_id *trid)
895 {
896 	return spdk_nvmf_transport_qpair_get_listen_trid(qpair, trid);
897 }
898 
899 int
900 spdk_nvmf_poll_group_add_transport(struct spdk_nvmf_poll_group *group,
901 				   struct spdk_nvmf_transport *transport)
902 {
903 	struct spdk_nvmf_transport_poll_group *tgroup;
904 
905 	TAILQ_FOREACH(tgroup, &group->tgroups, link) {
906 		if (tgroup->transport == transport) {
907 			/* Transport already in the poll group */
908 			return 0;
909 		}
910 	}
911 
912 	tgroup = spdk_nvmf_transport_poll_group_create(transport);
913 	if (!tgroup) {
914 		SPDK_ERRLOG("Unable to create poll group for transport\n");
915 		return -1;
916 	}
917 
918 	tgroup->group = group;
919 	TAILQ_INSERT_TAIL(&group->tgroups, tgroup, link);
920 
921 	return 0;
922 }
923 
924 static int
925 poll_group_update_subsystem(struct spdk_nvmf_poll_group *group,
926 			    struct spdk_nvmf_subsystem *subsystem)
927 {
928 	struct spdk_nvmf_subsystem_poll_group *sgroup;
929 	uint32_t new_num_ns, old_num_ns;
930 	uint32_t i, j;
931 	struct spdk_nvmf_ns *ns;
932 	struct spdk_nvmf_registrant *reg, *tmp;
933 	struct spdk_io_channel *ch;
934 	struct spdk_nvmf_subsystem_pg_ns_info *ns_info;
935 	struct spdk_nvmf_ctrlr *ctrlr;
936 	bool ns_changed;
937 
938 	/* Make sure our poll group has memory for this subsystem allocated */
939 	if (subsystem->id >= group->num_sgroups) {
940 		return -ENOMEM;
941 	}
942 
943 	sgroup = &group->sgroups[subsystem->id];
944 
945 	/* Make sure the array of namespace information is the correct size */
946 	new_num_ns = subsystem->max_nsid;
947 	old_num_ns = sgroup->num_ns;
948 
949 	ns_changed = false;
950 
951 	if (old_num_ns == 0) {
952 		if (new_num_ns > 0) {
953 			/* First allocation */
954 			sgroup->ns_info = calloc(new_num_ns, sizeof(struct spdk_nvmf_subsystem_pg_ns_info));
955 			if (!sgroup->ns_info) {
956 				return -ENOMEM;
957 			}
958 		}
959 	} else if (new_num_ns > old_num_ns) {
960 		void *buf;
961 
962 		/* Make the array larger */
963 		buf = realloc(sgroup->ns_info, new_num_ns * sizeof(struct spdk_nvmf_subsystem_pg_ns_info));
964 		if (!buf) {
965 			return -ENOMEM;
966 		}
967 
968 		sgroup->ns_info = buf;
969 
970 		/* Null out the new namespace information slots */
971 		for (i = old_num_ns; i < new_num_ns; i++) {
972 			memset(&sgroup->ns_info[i], 0, sizeof(struct spdk_nvmf_subsystem_pg_ns_info));
973 		}
974 	} else if (new_num_ns < old_num_ns) {
975 		void *buf;
976 
977 		/* Free the extra I/O channels */
978 		for (i = new_num_ns; i < old_num_ns; i++) {
979 			ns_info = &sgroup->ns_info[i];
980 
981 			if (ns_info->channel) {
982 				spdk_put_io_channel(ns_info->channel);
983 				ns_info->channel = NULL;
984 			}
985 		}
986 
987 		/* Make the array smaller */
988 		if (new_num_ns > 0) {
989 			buf = realloc(sgroup->ns_info, new_num_ns * sizeof(struct spdk_nvmf_subsystem_pg_ns_info));
990 			if (!buf) {
991 				return -ENOMEM;
992 			}
993 			sgroup->ns_info = buf;
994 		} else {
995 			free(sgroup->ns_info);
996 			sgroup->ns_info = NULL;
997 		}
998 	}
999 
1000 	sgroup->num_ns = new_num_ns;
1001 
1002 	/* Detect bdevs that were added or removed */
1003 	for (i = 0; i < sgroup->num_ns; i++) {
1004 		ns = subsystem->ns[i];
1005 		ns_info = &sgroup->ns_info[i];
1006 		ch = ns_info->channel;
1007 
1008 		if (ns == NULL && ch == NULL) {
1009 			/* Both NULL. Leave empty */
1010 		} else if (ns == NULL && ch != NULL) {
1011 			/* There was a channel here, but the namespace is gone. */
1012 			ns_changed = true;
1013 			spdk_put_io_channel(ch);
1014 			ns_info->channel = NULL;
1015 		} else if (ns != NULL && ch == NULL) {
1016 			/* A namespace appeared but there is no channel yet */
1017 			ns_changed = true;
1018 			ch = spdk_bdev_get_io_channel(ns->desc);
1019 			if (ch == NULL) {
1020 				SPDK_ERRLOG("Could not allocate I/O channel.\n");
1021 				return -ENOMEM;
1022 			}
1023 			ns_info->channel = ch;
1024 		} else if (spdk_uuid_compare(&ns_info->uuid, spdk_bdev_get_uuid(ns->bdev)) != 0) {
1025 			/* A namespace was here before, but was replaced by a new one. */
1026 			ns_changed = true;
1027 			spdk_put_io_channel(ns_info->channel);
1028 			memset(ns_info, 0, sizeof(*ns_info));
1029 
1030 			ch = spdk_bdev_get_io_channel(ns->desc);
1031 			if (ch == NULL) {
1032 				SPDK_ERRLOG("Could not allocate I/O channel.\n");
1033 				return -ENOMEM;
1034 			}
1035 			ns_info->channel = ch;
1036 		}
1037 
1038 		if (ns == NULL) {
1039 			memset(ns_info, 0, sizeof(*ns_info));
1040 		} else {
1041 			ns_info->uuid = *spdk_bdev_get_uuid(ns->bdev);
1042 			ns_info->crkey = ns->crkey;
1043 			ns_info->rtype = ns->rtype;
1044 			if (ns->holder) {
1045 				ns_info->holder_id = ns->holder->hostid;
1046 			}
1047 
1048 			memset(&ns_info->reg_hostid, 0, SPDK_NVMF_MAX_NUM_REGISTRANTS * sizeof(struct spdk_uuid));
1049 			j = 0;
1050 			TAILQ_FOREACH_SAFE(reg, &ns->registrants, link, tmp) {
1051 				if (j >= SPDK_NVMF_MAX_NUM_REGISTRANTS) {
1052 					SPDK_ERRLOG("Maximum %u registrants can support.\n", SPDK_NVMF_MAX_NUM_REGISTRANTS);
1053 					return -EINVAL;
1054 				}
1055 				ns_info->reg_hostid[j++] = reg->hostid;
1056 			}
1057 		}
1058 	}
1059 
1060 	if (ns_changed) {
1061 		TAILQ_FOREACH(ctrlr, &subsystem->ctrlrs, link) {
1062 			if (ctrlr->admin_qpair->group == group) {
1063 				spdk_nvmf_ctrlr_async_event_ns_notice(ctrlr);
1064 			}
1065 		}
1066 	}
1067 
1068 	return 0;
1069 }
1070 
1071 int
1072 spdk_nvmf_poll_group_update_subsystem(struct spdk_nvmf_poll_group *group,
1073 				      struct spdk_nvmf_subsystem *subsystem)
1074 {
1075 	return poll_group_update_subsystem(group, subsystem);
1076 }
1077 
1078 int
1079 spdk_nvmf_poll_group_add_subsystem(struct spdk_nvmf_poll_group *group,
1080 				   struct spdk_nvmf_subsystem *subsystem,
1081 				   spdk_nvmf_poll_group_mod_done cb_fn, void *cb_arg)
1082 {
1083 	int rc = 0;
1084 	struct spdk_nvmf_subsystem_poll_group *sgroup = &group->sgroups[subsystem->id];
1085 
1086 	TAILQ_INIT(&sgroup->queued);
1087 
1088 	rc = poll_group_update_subsystem(group, subsystem);
1089 	if (rc) {
1090 		spdk_nvmf_poll_group_remove_subsystem(group, subsystem, NULL, NULL);
1091 		goto fini;
1092 	}
1093 
1094 	sgroup->state = SPDK_NVMF_SUBSYSTEM_ACTIVE;
1095 fini:
1096 	if (cb_fn) {
1097 		cb_fn(cb_arg, rc);
1098 	}
1099 
1100 	return rc;
1101 }
1102 
1103 static void
1104 _nvmf_poll_group_remove_subsystem_cb(void *ctx, int status)
1105 {
1106 	struct nvmf_qpair_disconnect_many_ctx *qpair_ctx = ctx;
1107 	struct spdk_nvmf_subsystem *subsystem;
1108 	struct spdk_nvmf_poll_group *group;
1109 	struct spdk_nvmf_subsystem_poll_group *sgroup;
1110 	spdk_nvmf_poll_group_mod_done cpl_fn = NULL;
1111 	void *cpl_ctx = NULL;
1112 	uint32_t nsid;
1113 
1114 	group = qpair_ctx->group;
1115 	subsystem = qpair_ctx->subsystem;
1116 	cpl_fn = qpair_ctx->cpl_fn;
1117 	cpl_ctx = qpair_ctx->cpl_ctx;
1118 	sgroup = &group->sgroups[subsystem->id];
1119 
1120 	if (status) {
1121 		goto fini;
1122 	}
1123 
1124 	for (nsid = 0; nsid < sgroup->num_ns; nsid++) {
1125 		if (sgroup->ns_info[nsid].channel) {
1126 			spdk_put_io_channel(sgroup->ns_info[nsid].channel);
1127 			sgroup->ns_info[nsid].channel = NULL;
1128 		}
1129 	}
1130 
1131 	sgroup->num_ns = 0;
1132 	free(sgroup->ns_info);
1133 	sgroup->ns_info = NULL;
1134 fini:
1135 	free(qpair_ctx);
1136 	if (cpl_fn) {
1137 		cpl_fn(cpl_ctx, status);
1138 	}
1139 }
1140 
1141 static void
1142 _nvmf_subsystem_disconnect_next_qpair(void *ctx)
1143 {
1144 	struct spdk_nvmf_qpair *qpair;
1145 	struct nvmf_qpair_disconnect_many_ctx *qpair_ctx = ctx;
1146 	struct spdk_nvmf_subsystem *subsystem;
1147 	struct spdk_nvmf_poll_group *group;
1148 	int rc = 0;
1149 
1150 	group = qpair_ctx->group;
1151 	subsystem = qpair_ctx->subsystem;
1152 
1153 	TAILQ_FOREACH(qpair, &group->qpairs, link) {
1154 		if ((qpair->ctrlr != NULL) && (qpair->ctrlr->subsys == subsystem)) {
1155 			break;
1156 		}
1157 	}
1158 
1159 	if (qpair) {
1160 		rc = spdk_nvmf_qpair_disconnect(qpair, _nvmf_subsystem_disconnect_next_qpair, qpair_ctx);
1161 	}
1162 
1163 	if (!qpair || rc != 0) {
1164 		_nvmf_poll_group_remove_subsystem_cb(ctx, rc);
1165 	}
1166 	return;
1167 }
1168 
1169 void
1170 spdk_nvmf_poll_group_remove_subsystem(struct spdk_nvmf_poll_group *group,
1171 				      struct spdk_nvmf_subsystem *subsystem,
1172 				      spdk_nvmf_poll_group_mod_done cb_fn, void *cb_arg)
1173 {
1174 	struct spdk_nvmf_qpair *qpair;
1175 	struct spdk_nvmf_subsystem_poll_group *sgroup;
1176 	struct nvmf_qpair_disconnect_many_ctx *ctx;
1177 	int rc = 0;
1178 
1179 	ctx = calloc(1, sizeof(struct nvmf_qpair_disconnect_many_ctx));
1180 
1181 	if (!ctx) {
1182 		SPDK_ERRLOG("Unable to allocate memory for context to remove poll subsystem\n");
1183 		goto fini;
1184 	}
1185 
1186 	ctx->group = group;
1187 	ctx->subsystem = subsystem;
1188 	ctx->cpl_fn = cb_fn;
1189 	ctx->cpl_ctx = cb_arg;
1190 
1191 	sgroup = &group->sgroups[subsystem->id];
1192 	sgroup->state = SPDK_NVMF_SUBSYSTEM_INACTIVE;
1193 
1194 	TAILQ_FOREACH(qpair, &group->qpairs, link) {
1195 		if ((qpair->ctrlr != NULL) && (qpair->ctrlr->subsys == subsystem)) {
1196 			break;
1197 		}
1198 	}
1199 
1200 	if (qpair) {
1201 		rc = spdk_nvmf_qpair_disconnect(qpair, _nvmf_subsystem_disconnect_next_qpair, ctx);
1202 	} else {
1203 		/* call the callback immediately. It will handle any channel iteration */
1204 		_nvmf_poll_group_remove_subsystem_cb(ctx, 0);
1205 	}
1206 
1207 	if (rc != 0) {
1208 		free(ctx);
1209 		goto fini;
1210 	}
1211 
1212 	return;
1213 fini:
1214 	if (cb_fn) {
1215 		cb_fn(cb_arg, rc);
1216 	}
1217 }
1218 
1219 void
1220 spdk_nvmf_poll_group_pause_subsystem(struct spdk_nvmf_poll_group *group,
1221 				     struct spdk_nvmf_subsystem *subsystem,
1222 				     spdk_nvmf_poll_group_mod_done cb_fn, void *cb_arg)
1223 {
1224 	struct spdk_nvmf_subsystem_poll_group *sgroup;
1225 	int rc = 0;
1226 
1227 	if (subsystem->id >= group->num_sgroups) {
1228 		rc = -1;
1229 		goto fini;
1230 	}
1231 
1232 	sgroup = &group->sgroups[subsystem->id];
1233 	if (sgroup == NULL) {
1234 		rc = -1;
1235 		goto fini;
1236 	}
1237 
1238 	assert(sgroup->state == SPDK_NVMF_SUBSYSTEM_ACTIVE);
1239 	sgroup->state = SPDK_NVMF_SUBSYSTEM_PAUSING;
1240 
1241 	if (sgroup->io_outstanding > 0) {
1242 		sgroup->cb_fn = cb_fn;
1243 		sgroup->cb_arg = cb_arg;
1244 		return;
1245 	}
1246 
1247 	assert(sgroup->io_outstanding == 0);
1248 	sgroup->state = SPDK_NVMF_SUBSYSTEM_PAUSED;
1249 fini:
1250 	if (cb_fn) {
1251 		cb_fn(cb_arg, rc);
1252 	}
1253 }
1254 
1255 void
1256 spdk_nvmf_poll_group_resume_subsystem(struct spdk_nvmf_poll_group *group,
1257 				      struct spdk_nvmf_subsystem *subsystem,
1258 				      spdk_nvmf_poll_group_mod_done cb_fn, void *cb_arg)
1259 {
1260 	struct spdk_nvmf_request *req, *tmp;
1261 	struct spdk_nvmf_subsystem_poll_group *sgroup;
1262 	int rc = 0;
1263 
1264 	if (subsystem->id >= group->num_sgroups) {
1265 		rc = -1;
1266 		goto fini;
1267 	}
1268 
1269 	sgroup = &group->sgroups[subsystem->id];
1270 
1271 	assert(sgroup->state == SPDK_NVMF_SUBSYSTEM_PAUSED);
1272 
1273 	rc = poll_group_update_subsystem(group, subsystem);
1274 	if (rc) {
1275 		goto fini;
1276 	}
1277 
1278 	sgroup->state = SPDK_NVMF_SUBSYSTEM_ACTIVE;
1279 
1280 	/* Release all queued requests */
1281 	TAILQ_FOREACH_SAFE(req, &sgroup->queued, link, tmp) {
1282 		TAILQ_REMOVE(&sgroup->queued, req, link);
1283 		spdk_nvmf_request_exec(req);
1284 	}
1285 fini:
1286 	if (cb_fn) {
1287 		cb_fn(cb_arg, rc);
1288 	}
1289 }
1290 
1291 
1292 struct spdk_nvmf_poll_group *
1293 spdk_nvmf_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
1294 {
1295 	struct spdk_nvmf_transport_poll_group *tgroup;
1296 
1297 	tgroup = spdk_nvmf_transport_get_optimal_poll_group(qpair->transport, qpair);
1298 
1299 	if (tgroup == NULL) {
1300 		return NULL;
1301 	}
1302 
1303 	return tgroup->group;
1304 }
1305 
1306 int
1307 spdk_nvmf_poll_group_get_stat(struct spdk_nvmf_tgt *tgt,
1308 			      struct spdk_nvmf_poll_group_stat *stat)
1309 {
1310 	struct spdk_io_channel *ch;
1311 	struct spdk_nvmf_poll_group *group;
1312 
1313 	if (tgt == NULL || stat == NULL) {
1314 		return -EINVAL;
1315 	}
1316 
1317 	ch = spdk_get_io_channel(tgt);
1318 	group = spdk_io_channel_get_ctx(ch);
1319 	*stat = group->stat;
1320 	spdk_put_io_channel(ch);
1321 	return 0;
1322 }
1323