xref: /spdk/lib/nvme/nvme_rdma.c (revision 4d505568327cd1a2c2bf2bc36f497bc87129e401)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (C) 2016 Intel Corporation. All rights reserved.
3  *   Copyright (c) 2019-2021 Mellanox Technologies LTD. All rights reserved.
4  *   Copyright (c) 2021-2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
5  */
6 
7 /*
8  * NVMe over RDMA transport
9  */
10 
11 #include "spdk/stdinc.h"
12 
13 #include "spdk/assert.h"
14 #include "spdk/dma.h"
15 #include "spdk/log.h"
16 #include "spdk/trace.h"
17 #include "spdk/queue.h"
18 #include "spdk/nvme.h"
19 #include "spdk/nvmf_spec.h"
20 #include "spdk/string.h"
21 #include "spdk/endian.h"
22 #include "spdk/likely.h"
23 #include "spdk/config.h"
24 
25 #include "nvme_internal.h"
26 #include "spdk_internal/rdma.h"
27 
28 #define NVME_RDMA_TIME_OUT_IN_MS 2000
29 #define NVME_RDMA_RW_BUFFER_SIZE 131072
30 
31 /*
32  * NVME RDMA qpair Resource Defaults
33  */
34 #define NVME_RDMA_DEFAULT_TX_SGE		2
35 #define NVME_RDMA_DEFAULT_RX_SGE		1
36 
37 /* Max number of NVMe-oF SGL descriptors supported by the host */
38 #define NVME_RDMA_MAX_SGL_DESCRIPTORS		16
39 
40 /* number of STAILQ entries for holding pending RDMA CM events. */
41 #define NVME_RDMA_NUM_CM_EVENTS			256
42 
43 /* The default size for a shared rdma completion queue. */
44 #define DEFAULT_NVME_RDMA_CQ_SIZE		4096
45 
46 /*
47  * In the special case of a stale connection we don't expose a mechanism
48  * for the user to retry the connection so we need to handle it internally.
49  */
50 #define NVME_RDMA_STALE_CONN_RETRY_MAX		5
51 #define NVME_RDMA_STALE_CONN_RETRY_DELAY_US	10000
52 
53 /*
54  * Maximum value of transport_retry_count used by RDMA controller
55  */
56 #define NVME_RDMA_CTRLR_MAX_TRANSPORT_RETRY_COUNT	7
57 
58 /*
59  * Maximum value of transport_ack_timeout used by RDMA controller
60  */
61 #define NVME_RDMA_CTRLR_MAX_TRANSPORT_ACK_TIMEOUT	31
62 
63 /*
64  * Number of microseconds to wait until the lingering qpair becomes quiet.
65  */
66 #define NVME_RDMA_DISCONNECTED_QPAIR_TIMEOUT_US	1000000ull
67 
68 /*
69  * The max length of keyed SGL data block (3 bytes)
70  */
71 #define NVME_RDMA_MAX_KEYED_SGL_LENGTH ((1u << 24u) - 1)
72 
73 #define WC_PER_QPAIR(queue_depth)	(queue_depth * 2)
74 
75 #define NVME_RDMA_POLL_GROUP_CHECK_QPN(_rqpair, qpn)				\
76 	((_rqpair)->rdma_qp && (_rqpair)->rdma_qp->qp->qp_num == (qpn))	\
77 
78 struct nvme_rdma_memory_domain {
79 	TAILQ_ENTRY(nvme_rdma_memory_domain) link;
80 	uint32_t ref;
81 	struct ibv_pd *pd;
82 	struct spdk_memory_domain *domain;
83 	struct spdk_memory_domain_rdma_ctx rdma_ctx;
84 };
85 
86 enum nvme_rdma_wr_type {
87 	RDMA_WR_TYPE_RECV,
88 	RDMA_WR_TYPE_SEND,
89 };
90 
91 struct nvme_rdma_wr {
92 	/* Using this instead of the enum allows this struct to only occupy one byte. */
93 	uint8_t	type;
94 };
95 
96 struct spdk_nvmf_cmd {
97 	struct spdk_nvme_cmd cmd;
98 	struct spdk_nvme_sgl_descriptor sgl[NVME_RDMA_MAX_SGL_DESCRIPTORS];
99 };
100 
101 struct spdk_nvme_rdma_hooks g_nvme_hooks = {};
102 
103 /* STAILQ wrapper for cm events. */
104 struct nvme_rdma_cm_event_entry {
105 	struct rdma_cm_event			*evt;
106 	STAILQ_ENTRY(nvme_rdma_cm_event_entry)	link;
107 };
108 
109 /* NVMe RDMA transport extensions for spdk_nvme_ctrlr */
110 struct nvme_rdma_ctrlr {
111 	struct spdk_nvme_ctrlr			ctrlr;
112 
113 	uint16_t				max_sge;
114 
115 	struct rdma_event_channel		*cm_channel;
116 
117 	STAILQ_HEAD(, nvme_rdma_cm_event_entry)	pending_cm_events;
118 
119 	STAILQ_HEAD(, nvme_rdma_cm_event_entry)	free_cm_events;
120 
121 	struct nvme_rdma_cm_event_entry		*cm_events;
122 };
123 
124 struct nvme_rdma_poller_stats {
125 	uint64_t polls;
126 	uint64_t idle_polls;
127 	uint64_t queued_requests;
128 	uint64_t completions;
129 	struct spdk_rdma_qp_stats rdma_stats;
130 };
131 
132 struct nvme_rdma_poll_group;
133 struct nvme_rdma_rsps;
134 
135 struct nvme_rdma_poller {
136 	struct ibv_context		*device;
137 	struct ibv_cq			*cq;
138 	struct spdk_rdma_srq		*srq;
139 	struct nvme_rdma_rsps		*rsps;
140 	struct ibv_pd			*pd;
141 	struct spdk_rdma_mem_map	*mr_map;
142 	uint32_t			refcnt;
143 	int				required_num_wc;
144 	int				current_num_wc;
145 	struct nvme_rdma_poller_stats	stats;
146 	struct nvme_rdma_poll_group	*group;
147 	STAILQ_ENTRY(nvme_rdma_poller)	link;
148 };
149 
150 struct nvme_rdma_qpair;
151 
152 struct nvme_rdma_poll_group {
153 	struct spdk_nvme_transport_poll_group		group;
154 	STAILQ_HEAD(, nvme_rdma_poller)			pollers;
155 	uint32_t					num_pollers;
156 	TAILQ_HEAD(, nvme_rdma_qpair)			connecting_qpairs;
157 };
158 
159 enum nvme_rdma_qpair_state {
160 	NVME_RDMA_QPAIR_STATE_INVALID = 0,
161 	NVME_RDMA_QPAIR_STATE_STALE_CONN,
162 	NVME_RDMA_QPAIR_STATE_INITIALIZING,
163 	NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_SEND,
164 	NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_POLL,
165 	NVME_RDMA_QPAIR_STATE_RUNNING,
166 	NVME_RDMA_QPAIR_STATE_EXITING,
167 	NVME_RDMA_QPAIR_STATE_LINGERING,
168 	NVME_RDMA_QPAIR_STATE_EXITED,
169 };
170 
171 typedef int (*nvme_rdma_cm_event_cb)(struct nvme_rdma_qpair *rqpair, int ret);
172 
173 struct nvme_rdma_rsp_opts {
174 	uint16_t				num_entries;
175 	struct nvme_rdma_qpair			*rqpair;
176 	struct spdk_rdma_srq			*srq;
177 	struct spdk_rdma_mem_map		*mr_map;
178 };
179 
180 struct nvme_rdma_rsps {
181 	/* Parallel arrays of response buffers + response SGLs of size num_entries */
182 	struct ibv_sge				*rsp_sgls;
183 	struct spdk_nvme_rdma_rsp		*rsps;
184 
185 	struct ibv_recv_wr			*rsp_recv_wrs;
186 
187 	/* Count of outstanding recv objects */
188 	uint16_t				current_num_recvs;
189 
190 	uint16_t				num_entries;
191 };
192 
193 /* NVMe RDMA qpair extensions for spdk_nvme_qpair */
194 struct nvme_rdma_qpair {
195 	struct spdk_nvme_qpair			qpair;
196 
197 	struct spdk_rdma_qp			*rdma_qp;
198 	struct rdma_cm_id			*cm_id;
199 	struct ibv_cq				*cq;
200 	struct spdk_rdma_srq			*srq;
201 
202 	struct	spdk_nvme_rdma_req		*rdma_reqs;
203 
204 	uint32_t				max_send_sge;
205 
206 	uint32_t				max_recv_sge;
207 
208 	uint16_t				num_entries;
209 
210 	bool					delay_cmd_submit;
211 
212 	uint32_t				num_completions;
213 
214 	struct nvme_rdma_rsps			*rsps;
215 
216 	/*
217 	 * Array of num_entries NVMe commands registered as RDMA message buffers.
218 	 * Indexed by rdma_req->id.
219 	 */
220 	struct spdk_nvmf_cmd			*cmds;
221 
222 	struct spdk_rdma_mem_map		*mr_map;
223 
224 	TAILQ_HEAD(, spdk_nvme_rdma_req)	free_reqs;
225 	TAILQ_HEAD(, spdk_nvme_rdma_req)	outstanding_reqs;
226 
227 	struct nvme_rdma_memory_domain		*memory_domain;
228 
229 	/* Count of outstanding send objects */
230 	uint16_t				current_num_sends;
231 
232 	/* Placed at the end of the struct since it is not used frequently */
233 	struct rdma_cm_event			*evt;
234 	struct nvme_rdma_poller			*poller;
235 
236 	uint64_t				evt_timeout_ticks;
237 	nvme_rdma_cm_event_cb			evt_cb;
238 	enum rdma_cm_event_type			expected_evt_type;
239 
240 	enum nvme_rdma_qpair_state		state;
241 
242 	bool					in_connect_poll;
243 
244 	uint8_t					stale_conn_retry_count;
245 	bool					need_destroy;
246 
247 	TAILQ_ENTRY(nvme_rdma_qpair)		link_connecting;
248 };
249 
250 enum NVME_RDMA_COMPLETION_FLAGS {
251 	NVME_RDMA_SEND_COMPLETED = 1u << 0,
252 	NVME_RDMA_RECV_COMPLETED = 1u << 1,
253 };
254 
255 struct spdk_nvme_rdma_req {
256 	uint16_t				id;
257 	uint16_t				completion_flags: 2;
258 	uint16_t				reserved: 14;
259 	/* if completion of RDMA_RECV received before RDMA_SEND, we will complete nvme request
260 	 * during processing of RDMA_SEND. To complete the request we must know the response
261 	 * received in RDMA_RECV, so store it in this field */
262 	struct spdk_nvme_rdma_rsp		*rdma_rsp;
263 
264 	struct nvme_rdma_wr			rdma_wr;
265 
266 	struct ibv_send_wr			send_wr;
267 
268 	struct nvme_request			*req;
269 
270 	struct ibv_sge				send_sgl[NVME_RDMA_DEFAULT_TX_SGE];
271 
272 	TAILQ_ENTRY(spdk_nvme_rdma_req)		link;
273 };
274 
275 struct spdk_nvme_rdma_rsp {
276 	struct spdk_nvme_cpl	cpl;
277 	struct nvme_rdma_qpair	*rqpair;
278 	struct ibv_recv_wr	*recv_wr;
279 	struct nvme_rdma_wr	rdma_wr;
280 };
281 
282 struct nvme_rdma_memory_translation_ctx {
283 	void *addr;
284 	size_t length;
285 	uint32_t lkey;
286 	uint32_t rkey;
287 };
288 
289 static const char *rdma_cm_event_str[] = {
290 	"RDMA_CM_EVENT_ADDR_RESOLVED",
291 	"RDMA_CM_EVENT_ADDR_ERROR",
292 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
293 	"RDMA_CM_EVENT_ROUTE_ERROR",
294 	"RDMA_CM_EVENT_CONNECT_REQUEST",
295 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
296 	"RDMA_CM_EVENT_CONNECT_ERROR",
297 	"RDMA_CM_EVENT_UNREACHABLE",
298 	"RDMA_CM_EVENT_REJECTED",
299 	"RDMA_CM_EVENT_ESTABLISHED",
300 	"RDMA_CM_EVENT_DISCONNECTED",
301 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
302 	"RDMA_CM_EVENT_MULTICAST_JOIN",
303 	"RDMA_CM_EVENT_MULTICAST_ERROR",
304 	"RDMA_CM_EVENT_ADDR_CHANGE",
305 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
306 };
307 
308 static struct nvme_rdma_poller *nvme_rdma_poll_group_get_poller(struct nvme_rdma_poll_group *group,
309 		struct ibv_context *device);
310 static void nvme_rdma_poll_group_put_poller(struct nvme_rdma_poll_group *group,
311 		struct nvme_rdma_poller *poller);
312 
313 static TAILQ_HEAD(, nvme_rdma_memory_domain) g_memory_domains = TAILQ_HEAD_INITIALIZER(
314 			g_memory_domains);
315 static pthread_mutex_t g_memory_domains_lock = PTHREAD_MUTEX_INITIALIZER;
316 
317 static struct nvme_rdma_memory_domain *
318 nvme_rdma_get_memory_domain(struct ibv_pd *pd)
319 {
320 	struct nvme_rdma_memory_domain *domain = NULL;
321 	struct spdk_memory_domain_ctx ctx;
322 	int rc;
323 
324 	pthread_mutex_lock(&g_memory_domains_lock);
325 
326 	TAILQ_FOREACH(domain, &g_memory_domains, link) {
327 		if (domain->pd == pd) {
328 			domain->ref++;
329 			pthread_mutex_unlock(&g_memory_domains_lock);
330 			return domain;
331 		}
332 	}
333 
334 	domain = calloc(1, sizeof(*domain));
335 	if (!domain) {
336 		SPDK_ERRLOG("Memory allocation failed\n");
337 		pthread_mutex_unlock(&g_memory_domains_lock);
338 		return NULL;
339 	}
340 
341 	domain->rdma_ctx.size = sizeof(domain->rdma_ctx);
342 	domain->rdma_ctx.ibv_pd = pd;
343 	ctx.size = sizeof(ctx);
344 	ctx.user_ctx = &domain->rdma_ctx;
345 
346 	rc = spdk_memory_domain_create(&domain->domain, SPDK_DMA_DEVICE_TYPE_RDMA, &ctx,
347 				       SPDK_RDMA_DMA_DEVICE);
348 	if (rc) {
349 		SPDK_ERRLOG("Failed to create memory domain\n");
350 		free(domain);
351 		pthread_mutex_unlock(&g_memory_domains_lock);
352 		return NULL;
353 	}
354 
355 	domain->pd = pd;
356 	domain->ref = 1;
357 	TAILQ_INSERT_TAIL(&g_memory_domains, domain, link);
358 
359 	pthread_mutex_unlock(&g_memory_domains_lock);
360 
361 	return domain;
362 }
363 
364 static void
365 nvme_rdma_put_memory_domain(struct nvme_rdma_memory_domain *device)
366 {
367 	if (!device) {
368 		return;
369 	}
370 
371 	pthread_mutex_lock(&g_memory_domains_lock);
372 
373 	assert(device->ref > 0);
374 
375 	device->ref--;
376 
377 	if (device->ref == 0) {
378 		spdk_memory_domain_destroy(device->domain);
379 		TAILQ_REMOVE(&g_memory_domains, device, link);
380 		free(device);
381 	}
382 
383 	pthread_mutex_unlock(&g_memory_domains_lock);
384 }
385 
386 static int nvme_rdma_ctrlr_delete_io_qpair(struct spdk_nvme_ctrlr *ctrlr,
387 		struct spdk_nvme_qpair *qpair);
388 
389 static inline struct nvme_rdma_qpair *
390 nvme_rdma_qpair(struct spdk_nvme_qpair *qpair)
391 {
392 	assert(qpair->trtype == SPDK_NVME_TRANSPORT_RDMA);
393 	return SPDK_CONTAINEROF(qpair, struct nvme_rdma_qpair, qpair);
394 }
395 
396 static inline struct nvme_rdma_poll_group *
397 nvme_rdma_poll_group(struct spdk_nvme_transport_poll_group *group)
398 {
399 	return (SPDK_CONTAINEROF(group, struct nvme_rdma_poll_group, group));
400 }
401 
402 static inline struct nvme_rdma_ctrlr *
403 nvme_rdma_ctrlr(struct spdk_nvme_ctrlr *ctrlr)
404 {
405 	assert(ctrlr->trid.trtype == SPDK_NVME_TRANSPORT_RDMA);
406 	return SPDK_CONTAINEROF(ctrlr, struct nvme_rdma_ctrlr, ctrlr);
407 }
408 
409 static struct spdk_nvme_rdma_req *
410 nvme_rdma_req_get(struct nvme_rdma_qpair *rqpair)
411 {
412 	struct spdk_nvme_rdma_req *rdma_req;
413 
414 	rdma_req = TAILQ_FIRST(&rqpair->free_reqs);
415 	if (rdma_req) {
416 		TAILQ_REMOVE(&rqpair->free_reqs, rdma_req, link);
417 	}
418 
419 	return rdma_req;
420 }
421 
422 static void
423 nvme_rdma_req_put(struct nvme_rdma_qpair *rqpair, struct spdk_nvme_rdma_req *rdma_req)
424 {
425 	rdma_req->completion_flags = 0;
426 	rdma_req->req = NULL;
427 	rdma_req->rdma_rsp = NULL;
428 	TAILQ_INSERT_HEAD(&rqpair->free_reqs, rdma_req, link);
429 }
430 
431 static void
432 nvme_rdma_req_complete(struct spdk_nvme_rdma_req *rdma_req,
433 		       struct spdk_nvme_cpl *rsp,
434 		       bool print_on_error)
435 {
436 	struct nvme_request *req = rdma_req->req;
437 	struct nvme_rdma_qpair *rqpair;
438 	struct spdk_nvme_qpair *qpair;
439 	bool error, print_error;
440 
441 	assert(req != NULL);
442 
443 	qpair = req->qpair;
444 	rqpair = nvme_rdma_qpair(qpair);
445 
446 	error = spdk_nvme_cpl_is_error(rsp);
447 	print_error = error && print_on_error && !qpair->ctrlr->opts.disable_error_logging;
448 
449 	if (print_error) {
450 		spdk_nvme_qpair_print_command(qpair, &req->cmd);
451 	}
452 
453 	if (print_error || SPDK_DEBUGLOG_FLAG_ENABLED("nvme")) {
454 		spdk_nvme_qpair_print_completion(qpair, rsp);
455 	}
456 
457 	TAILQ_REMOVE(&rqpair->outstanding_reqs, rdma_req, link);
458 
459 	nvme_complete_request(req->cb_fn, req->cb_arg, qpair, req, rsp);
460 	nvme_rdma_req_put(rqpair, rdma_req);
461 }
462 
463 static const char *
464 nvme_rdma_cm_event_str_get(uint32_t event)
465 {
466 	if (event < SPDK_COUNTOF(rdma_cm_event_str)) {
467 		return rdma_cm_event_str[event];
468 	} else {
469 		return "Undefined";
470 	}
471 }
472 
473 
474 static int
475 nvme_rdma_qpair_process_cm_event(struct nvme_rdma_qpair *rqpair)
476 {
477 	struct rdma_cm_event				*event = rqpair->evt;
478 	struct spdk_nvmf_rdma_accept_private_data	*accept_data;
479 	int						rc = 0;
480 
481 	if (event) {
482 		switch (event->event) {
483 		case RDMA_CM_EVENT_ADDR_RESOLVED:
484 		case RDMA_CM_EVENT_ADDR_ERROR:
485 		case RDMA_CM_EVENT_ROUTE_RESOLVED:
486 		case RDMA_CM_EVENT_ROUTE_ERROR:
487 			break;
488 		case RDMA_CM_EVENT_CONNECT_REQUEST:
489 			break;
490 		case RDMA_CM_EVENT_CONNECT_ERROR:
491 			break;
492 		case RDMA_CM_EVENT_UNREACHABLE:
493 		case RDMA_CM_EVENT_REJECTED:
494 			break;
495 		case RDMA_CM_EVENT_CONNECT_RESPONSE:
496 			rc = spdk_rdma_qp_complete_connect(rqpair->rdma_qp);
497 		/* fall through */
498 		case RDMA_CM_EVENT_ESTABLISHED:
499 			accept_data = (struct spdk_nvmf_rdma_accept_private_data *)event->param.conn.private_data;
500 			if (accept_data == NULL) {
501 				rc = -1;
502 			} else {
503 				SPDK_DEBUGLOG(nvme, "Requested queue depth %d. Target receive queue depth %d.\n",
504 					      rqpair->num_entries + 1, accept_data->crqsize);
505 			}
506 			break;
507 		case RDMA_CM_EVENT_DISCONNECTED:
508 			rqpair->qpair.transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_REMOTE;
509 			break;
510 		case RDMA_CM_EVENT_DEVICE_REMOVAL:
511 			rqpair->qpair.transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_LOCAL;
512 			rqpair->need_destroy = true;
513 			break;
514 		case RDMA_CM_EVENT_MULTICAST_JOIN:
515 		case RDMA_CM_EVENT_MULTICAST_ERROR:
516 			break;
517 		case RDMA_CM_EVENT_ADDR_CHANGE:
518 			rqpair->qpair.transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_LOCAL;
519 			break;
520 		case RDMA_CM_EVENT_TIMEWAIT_EXIT:
521 			break;
522 		default:
523 			SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
524 			break;
525 		}
526 		rqpair->evt = NULL;
527 		rdma_ack_cm_event(event);
528 	}
529 
530 	return rc;
531 }
532 
533 /*
534  * This function must be called under the nvme controller's lock
535  * because it touches global controller variables. The lock is taken
536  * by the generic transport code before invoking a few of the functions
537  * in this file: nvme_rdma_ctrlr_connect_qpair, nvme_rdma_ctrlr_delete_io_qpair,
538  * and conditionally nvme_rdma_qpair_process_completions when it is calling
539  * completions on the admin qpair. When adding a new call to this function, please
540  * verify that it is in a situation where it falls under the lock.
541  */
542 static int
543 nvme_rdma_poll_events(struct nvme_rdma_ctrlr *rctrlr)
544 {
545 	struct nvme_rdma_cm_event_entry	*entry, *tmp;
546 	struct nvme_rdma_qpair		*event_qpair;
547 	struct rdma_cm_event		*event;
548 	struct rdma_event_channel	*channel = rctrlr->cm_channel;
549 
550 	STAILQ_FOREACH_SAFE(entry, &rctrlr->pending_cm_events, link, tmp) {
551 		event_qpair = entry->evt->id->context;
552 		if (event_qpair->evt == NULL) {
553 			event_qpair->evt = entry->evt;
554 			STAILQ_REMOVE(&rctrlr->pending_cm_events, entry, nvme_rdma_cm_event_entry, link);
555 			STAILQ_INSERT_HEAD(&rctrlr->free_cm_events, entry, link);
556 		}
557 	}
558 
559 	while (rdma_get_cm_event(channel, &event) == 0) {
560 		event_qpair = event->id->context;
561 		if (event_qpair->evt == NULL) {
562 			event_qpair->evt = event;
563 		} else {
564 			assert(rctrlr == nvme_rdma_ctrlr(event_qpair->qpair.ctrlr));
565 			entry = STAILQ_FIRST(&rctrlr->free_cm_events);
566 			if (entry == NULL) {
567 				rdma_ack_cm_event(event);
568 				return -ENOMEM;
569 			}
570 			STAILQ_REMOVE(&rctrlr->free_cm_events, entry, nvme_rdma_cm_event_entry, link);
571 			entry->evt = event;
572 			STAILQ_INSERT_TAIL(&rctrlr->pending_cm_events, entry, link);
573 		}
574 	}
575 
576 	/* rdma_get_cm_event() returns -1 on error. If an error occurs, errno
577 	 * will be set to indicate the failure reason. So return negated errno here.
578 	 */
579 	return -errno;
580 }
581 
582 static int
583 nvme_rdma_validate_cm_event(enum rdma_cm_event_type expected_evt_type,
584 			    struct rdma_cm_event *reaped_evt)
585 {
586 	int rc = -EBADMSG;
587 
588 	if (expected_evt_type == reaped_evt->event) {
589 		return 0;
590 	}
591 
592 	switch (expected_evt_type) {
593 	case RDMA_CM_EVENT_ESTABLISHED:
594 		/*
595 		 * There is an enum ib_cm_rej_reason in the kernel headers that sets 10 as
596 		 * IB_CM_REJ_STALE_CONN. I can't find the corresponding userspace but we get
597 		 * the same values here.
598 		 */
599 		if (reaped_evt->event == RDMA_CM_EVENT_REJECTED && reaped_evt->status == 10) {
600 			rc = -ESTALE;
601 		} else if (reaped_evt->event == RDMA_CM_EVENT_CONNECT_RESPONSE) {
602 			/*
603 			 *  If we are using a qpair which is not created using rdma cm API
604 			 *  then we will receive RDMA_CM_EVENT_CONNECT_RESPONSE instead of
605 			 *  RDMA_CM_EVENT_ESTABLISHED.
606 			 */
607 			return 0;
608 		}
609 		break;
610 	default:
611 		break;
612 	}
613 
614 	SPDK_ERRLOG("Expected %s but received %s (%d) from CM event channel (status = %d)\n",
615 		    nvme_rdma_cm_event_str_get(expected_evt_type),
616 		    nvme_rdma_cm_event_str_get(reaped_evt->event), reaped_evt->event,
617 		    reaped_evt->status);
618 	return rc;
619 }
620 
621 static int
622 nvme_rdma_process_event_start(struct nvme_rdma_qpair *rqpair,
623 			      enum rdma_cm_event_type evt,
624 			      nvme_rdma_cm_event_cb evt_cb)
625 {
626 	int	rc;
627 
628 	assert(evt_cb != NULL);
629 
630 	if (rqpair->evt != NULL) {
631 		rc = nvme_rdma_qpair_process_cm_event(rqpair);
632 		if (rc) {
633 			return rc;
634 		}
635 	}
636 
637 	rqpair->expected_evt_type = evt;
638 	rqpair->evt_cb = evt_cb;
639 	rqpair->evt_timeout_ticks = (g_spdk_nvme_transport_opts.rdma_cm_event_timeout_ms * 1000 *
640 				     spdk_get_ticks_hz()) / SPDK_SEC_TO_USEC + spdk_get_ticks();
641 
642 	return 0;
643 }
644 
645 static int
646 nvme_rdma_process_event_poll(struct nvme_rdma_qpair *rqpair)
647 {
648 	struct nvme_rdma_ctrlr	*rctrlr;
649 	int	rc = 0, rc2;
650 
651 	rctrlr = nvme_rdma_ctrlr(rqpair->qpair.ctrlr);
652 	assert(rctrlr != NULL);
653 
654 	if (!rqpair->evt && spdk_get_ticks() < rqpair->evt_timeout_ticks) {
655 		rc = nvme_rdma_poll_events(rctrlr);
656 		if (rc == -EAGAIN || rc == -EWOULDBLOCK) {
657 			return rc;
658 		}
659 	}
660 
661 	if (rqpair->evt == NULL) {
662 		rc = -EADDRNOTAVAIL;
663 		goto exit;
664 	}
665 
666 	rc = nvme_rdma_validate_cm_event(rqpair->expected_evt_type, rqpair->evt);
667 
668 	rc2 = nvme_rdma_qpair_process_cm_event(rqpair);
669 	/* bad message takes precedence over the other error codes from processing the event. */
670 	rc = rc == 0 ? rc2 : rc;
671 
672 exit:
673 	assert(rqpair->evt_cb != NULL);
674 	return rqpair->evt_cb(rqpair, rc);
675 }
676 
677 static int
678 nvme_rdma_resize_cq(struct nvme_rdma_qpair *rqpair, struct nvme_rdma_poller *poller)
679 {
680 	int	current_num_wc, required_num_wc;
681 	int	max_cq_size;
682 
683 	required_num_wc = poller->required_num_wc + WC_PER_QPAIR(rqpair->num_entries);
684 	current_num_wc = poller->current_num_wc;
685 	if (current_num_wc < required_num_wc) {
686 		current_num_wc = spdk_max(current_num_wc * 2, required_num_wc);
687 	}
688 
689 	max_cq_size = g_spdk_nvme_transport_opts.rdma_max_cq_size;
690 	if (max_cq_size != 0 && current_num_wc > max_cq_size) {
691 		current_num_wc = max_cq_size;
692 	}
693 
694 	if (poller->current_num_wc != current_num_wc) {
695 		SPDK_DEBUGLOG(nvme, "Resize RDMA CQ from %d to %d\n", poller->current_num_wc,
696 			      current_num_wc);
697 		if (ibv_resize_cq(poller->cq, current_num_wc)) {
698 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
699 			return -1;
700 		}
701 
702 		poller->current_num_wc = current_num_wc;
703 	}
704 
705 	poller->required_num_wc = required_num_wc;
706 	return 0;
707 }
708 
709 static int
710 nvme_rdma_qpair_set_poller(struct spdk_nvme_qpair *qpair)
711 {
712 	struct nvme_rdma_qpair          *rqpair = nvme_rdma_qpair(qpair);
713 	struct nvme_rdma_poll_group     *group = nvme_rdma_poll_group(qpair->poll_group);
714 	struct nvme_rdma_poller         *poller;
715 
716 	assert(rqpair->cq == NULL);
717 
718 	poller = nvme_rdma_poll_group_get_poller(group, rqpair->cm_id->verbs);
719 	if (!poller) {
720 		SPDK_ERRLOG("Unable to find a cq for qpair %p on poll group %p\n", qpair, qpair->poll_group);
721 		return -EINVAL;
722 	}
723 
724 	if (!poller->srq) {
725 		if (nvme_rdma_resize_cq(rqpair, poller)) {
726 			nvme_rdma_poll_group_put_poller(group, poller);
727 			return -EPROTO;
728 		}
729 	}
730 
731 	rqpair->cq = poller->cq;
732 	rqpair->srq = poller->srq;
733 	if (rqpair->srq) {
734 		rqpair->rsps = poller->rsps;
735 	}
736 	rqpair->poller = poller;
737 	return 0;
738 }
739 
740 static int
741 nvme_rdma_qpair_init(struct nvme_rdma_qpair *rqpair)
742 {
743 	int			rc;
744 	struct spdk_rdma_qp_init_attr	attr = {};
745 	struct ibv_device_attr	dev_attr;
746 	struct nvme_rdma_ctrlr	*rctrlr;
747 	uint32_t num_cqe, max_num_cqe;
748 
749 	rc = ibv_query_device(rqpair->cm_id->verbs, &dev_attr);
750 	if (rc != 0) {
751 		SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
752 		return -1;
753 	}
754 
755 	if (rqpair->qpair.poll_group) {
756 		assert(!rqpair->cq);
757 		rc = nvme_rdma_qpair_set_poller(&rqpair->qpair);
758 		if (rc) {
759 			SPDK_ERRLOG("Unable to activate the rdmaqpair.\n");
760 			return -1;
761 		}
762 		assert(rqpair->cq);
763 	} else {
764 		num_cqe = rqpair->num_entries * 2;
765 		max_num_cqe = g_spdk_nvme_transport_opts.rdma_max_cq_size;
766 		if (max_num_cqe != 0 && num_cqe > max_num_cqe) {
767 			num_cqe = max_num_cqe;
768 		}
769 		rqpair->cq = ibv_create_cq(rqpair->cm_id->verbs, num_cqe, rqpair, NULL, 0);
770 		if (!rqpair->cq) {
771 			SPDK_ERRLOG("Unable to create completion queue: errno %d: %s\n", errno, spdk_strerror(errno));
772 			return -1;
773 		}
774 	}
775 
776 	rctrlr = nvme_rdma_ctrlr(rqpair->qpair.ctrlr);
777 	if (g_nvme_hooks.get_ibv_pd) {
778 		attr.pd = g_nvme_hooks.get_ibv_pd(&rctrlr->ctrlr.trid, rqpair->cm_id->verbs);
779 	} else {
780 		attr.pd = spdk_rdma_get_pd(rqpair->cm_id->verbs);
781 	}
782 
783 	attr.stats =		rqpair->poller ? &rqpair->poller->stats.rdma_stats : NULL;
784 	attr.send_cq		= rqpair->cq;
785 	attr.recv_cq		= rqpair->cq;
786 	attr.cap.max_send_wr	= rqpair->num_entries; /* SEND operations */
787 	if (rqpair->srq) {
788 		attr.srq	= rqpair->srq->srq;
789 	} else {
790 		attr.cap.max_recv_wr = rqpair->num_entries; /* RECV operations */
791 	}
792 	attr.cap.max_send_sge	= spdk_min(NVME_RDMA_DEFAULT_TX_SGE, dev_attr.max_sge);
793 	attr.cap.max_recv_sge	= spdk_min(NVME_RDMA_DEFAULT_RX_SGE, dev_attr.max_sge);
794 
795 	rqpair->rdma_qp = spdk_rdma_qp_create(rqpair->cm_id, &attr);
796 
797 	if (!rqpair->rdma_qp) {
798 		return -1;
799 	}
800 
801 	rqpair->memory_domain = nvme_rdma_get_memory_domain(rqpair->rdma_qp->qp->pd);
802 	if (!rqpair->memory_domain) {
803 		SPDK_ERRLOG("Failed to get memory domain\n");
804 		return -1;
805 	}
806 
807 	/* ibv_create_qp will change the values in attr.cap. Make sure we store the proper value. */
808 	rqpair->max_send_sge = spdk_min(NVME_RDMA_DEFAULT_TX_SGE, attr.cap.max_send_sge);
809 	rqpair->max_recv_sge = spdk_min(NVME_RDMA_DEFAULT_RX_SGE, attr.cap.max_recv_sge);
810 	rqpair->current_num_sends = 0;
811 
812 	rqpair->cm_id->context = rqpair;
813 
814 	return 0;
815 }
816 
817 static void
818 nvme_rdma_reset_failed_sends(struct nvme_rdma_qpair *rqpair,
819 			     struct ibv_send_wr *bad_send_wr, int rc)
820 {
821 	SPDK_ERRLOG("Failed to post WRs on send queue, errno %d (%s), bad_wr %p\n",
822 		    rc, spdk_strerror(rc), bad_send_wr);
823 	while (bad_send_wr != NULL) {
824 		assert(rqpair->current_num_sends > 0);
825 		rqpair->current_num_sends--;
826 		bad_send_wr = bad_send_wr->next;
827 	}
828 }
829 
830 static void
831 nvme_rdma_reset_failed_recvs(struct nvme_rdma_rsps *rsps,
832 			     struct ibv_recv_wr *bad_recv_wr, int rc)
833 {
834 	SPDK_ERRLOG("Failed to post WRs on receive queue, errno %d (%s), bad_wr %p\n",
835 		    rc, spdk_strerror(rc), bad_recv_wr);
836 	while (bad_recv_wr != NULL) {
837 		assert(rsps->current_num_recvs > 0);
838 		rsps->current_num_recvs--;
839 		bad_recv_wr = bad_recv_wr->next;
840 	}
841 }
842 
843 static inline int
844 nvme_rdma_qpair_submit_sends(struct nvme_rdma_qpair *rqpair)
845 {
846 	struct ibv_send_wr *bad_send_wr = NULL;
847 	int rc;
848 
849 	rc = spdk_rdma_qp_flush_send_wrs(rqpair->rdma_qp, &bad_send_wr);
850 
851 	if (spdk_unlikely(rc)) {
852 		nvme_rdma_reset_failed_sends(rqpair, bad_send_wr, rc);
853 	}
854 
855 	return rc;
856 }
857 
858 static inline int
859 nvme_rdma_qpair_submit_recvs(struct nvme_rdma_qpair *rqpair)
860 {
861 	struct ibv_recv_wr *bad_recv_wr;
862 	int rc = 0;
863 
864 	rc = spdk_rdma_qp_flush_recv_wrs(rqpair->rdma_qp, &bad_recv_wr);
865 	if (spdk_unlikely(rc)) {
866 		nvme_rdma_reset_failed_recvs(rqpair->rsps, bad_recv_wr, rc);
867 	}
868 
869 	return rc;
870 }
871 
872 static inline int
873 nvme_rdma_poller_submit_recvs(struct nvme_rdma_poller *poller)
874 {
875 	struct ibv_recv_wr *bad_recv_wr;
876 	int rc;
877 
878 	rc = spdk_rdma_srq_flush_recv_wrs(poller->srq, &bad_recv_wr);
879 	if (spdk_unlikely(rc)) {
880 		nvme_rdma_reset_failed_recvs(poller->rsps, bad_recv_wr, rc);
881 	}
882 
883 	return rc;
884 }
885 
886 #define nvme_rdma_trace_ibv_sge(sg_list) \
887 	if (sg_list) { \
888 		SPDK_DEBUGLOG(nvme, "local addr %p length 0x%x lkey 0x%x\n", \
889 			      (void *)(sg_list)->addr, (sg_list)->length, (sg_list)->lkey); \
890 	}
891 
892 static void
893 nvme_rdma_free_rsps(struct nvme_rdma_rsps *rsps)
894 {
895 	if (!rsps) {
896 		return;
897 	}
898 
899 	spdk_free(rsps->rsps);
900 	spdk_free(rsps->rsp_sgls);
901 	spdk_free(rsps->rsp_recv_wrs);
902 	spdk_free(rsps);
903 }
904 
905 static struct nvme_rdma_rsps *
906 nvme_rdma_create_rsps(struct nvme_rdma_rsp_opts *opts)
907 {
908 	struct nvme_rdma_rsps *rsps;
909 	struct spdk_rdma_memory_translation translation;
910 	uint16_t i;
911 	int rc;
912 
913 	rsps = spdk_zmalloc(sizeof(*rsps), 0, NULL, SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
914 	if (!rsps) {
915 		SPDK_ERRLOG("Failed to allocate rsps object\n");
916 		return NULL;
917 	}
918 
919 	rsps->rsp_sgls = spdk_zmalloc(opts->num_entries * sizeof(*rsps->rsp_sgls), 0, NULL,
920 				      SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
921 	if (!rsps->rsp_sgls) {
922 		SPDK_ERRLOG("Failed to allocate rsp_sgls\n");
923 		goto fail;
924 	}
925 
926 	rsps->rsp_recv_wrs = spdk_zmalloc(opts->num_entries * sizeof(*rsps->rsp_recv_wrs), 0, NULL,
927 					  SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
928 	if (!rsps->rsp_recv_wrs) {
929 		SPDK_ERRLOG("Failed to allocate rsp_recv_wrs\n");
930 		goto fail;
931 	}
932 
933 	rsps->rsps = spdk_zmalloc(opts->num_entries * sizeof(*rsps->rsps), 0, NULL,
934 				  SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
935 	if (!rsps->rsps) {
936 		SPDK_ERRLOG("can not allocate rdma rsps\n");
937 		goto fail;
938 	}
939 
940 	for (i = 0; i < opts->num_entries; i++) {
941 		struct ibv_sge *rsp_sgl = &rsps->rsp_sgls[i];
942 		struct spdk_nvme_rdma_rsp *rsp = &rsps->rsps[i];
943 		struct ibv_recv_wr *recv_wr = &rsps->rsp_recv_wrs[i];
944 
945 		rsp->rqpair = opts->rqpair;
946 		rsp->rdma_wr.type = RDMA_WR_TYPE_RECV;
947 		rsp->recv_wr = recv_wr;
948 		rsp_sgl->addr = (uint64_t)rsp;
949 		rsp_sgl->length = sizeof(struct spdk_nvme_cpl);
950 		rc = spdk_rdma_get_translation(opts->mr_map, rsp, sizeof(*rsp), &translation);
951 		if (rc) {
952 			goto fail;
953 		}
954 		rsp_sgl->lkey = spdk_rdma_memory_translation_get_lkey(&translation);
955 
956 		recv_wr->wr_id = (uint64_t)&rsp->rdma_wr;
957 		recv_wr->next = NULL;
958 		recv_wr->sg_list = rsp_sgl;
959 		recv_wr->num_sge = 1;
960 
961 		nvme_rdma_trace_ibv_sge(recv_wr->sg_list);
962 
963 		if (opts->rqpair) {
964 			spdk_rdma_qp_queue_recv_wrs(opts->rqpair->rdma_qp, recv_wr);
965 		} else {
966 			spdk_rdma_srq_queue_recv_wrs(opts->srq, recv_wr);
967 		}
968 	}
969 
970 	rsps->num_entries = opts->num_entries;
971 	rsps->current_num_recvs = opts->num_entries;
972 
973 	return rsps;
974 fail:
975 	nvme_rdma_free_rsps(rsps);
976 	return NULL;
977 }
978 
979 static void
980 nvme_rdma_free_reqs(struct nvme_rdma_qpair *rqpair)
981 {
982 	if (!rqpair->rdma_reqs) {
983 		return;
984 	}
985 
986 	spdk_free(rqpair->cmds);
987 	rqpair->cmds = NULL;
988 
989 	spdk_free(rqpair->rdma_reqs);
990 	rqpair->rdma_reqs = NULL;
991 }
992 
993 static int
994 nvme_rdma_create_reqs(struct nvme_rdma_qpair *rqpair)
995 {
996 	struct spdk_rdma_memory_translation translation;
997 	uint16_t i;
998 	int rc;
999 
1000 	assert(!rqpair->rdma_reqs);
1001 	rqpair->rdma_reqs = spdk_zmalloc(rqpair->num_entries * sizeof(struct spdk_nvme_rdma_req), 0, NULL,
1002 					 SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
1003 	if (rqpair->rdma_reqs == NULL) {
1004 		SPDK_ERRLOG("Failed to allocate rdma_reqs\n");
1005 		goto fail;
1006 	}
1007 
1008 	assert(!rqpair->cmds);
1009 	rqpair->cmds = spdk_zmalloc(rqpair->num_entries * sizeof(*rqpair->cmds), 0, NULL,
1010 				    SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
1011 	if (!rqpair->cmds) {
1012 		SPDK_ERRLOG("Failed to allocate RDMA cmds\n");
1013 		goto fail;
1014 	}
1015 
1016 	TAILQ_INIT(&rqpair->free_reqs);
1017 	TAILQ_INIT(&rqpair->outstanding_reqs);
1018 	for (i = 0; i < rqpair->num_entries; i++) {
1019 		struct spdk_nvme_rdma_req	*rdma_req;
1020 		struct spdk_nvmf_cmd		*cmd;
1021 
1022 		rdma_req = &rqpair->rdma_reqs[i];
1023 		rdma_req->rdma_wr.type = RDMA_WR_TYPE_SEND;
1024 		cmd = &rqpair->cmds[i];
1025 
1026 		rdma_req->id = i;
1027 
1028 		rc = spdk_rdma_get_translation(rqpair->mr_map, cmd, sizeof(*cmd), &translation);
1029 		if (rc) {
1030 			goto fail;
1031 		}
1032 		rdma_req->send_sgl[0].lkey = spdk_rdma_memory_translation_get_lkey(&translation);
1033 
1034 		/* The first RDMA sgl element will always point
1035 		 * at this data structure. Depending on whether
1036 		 * an NVMe-oF SGL is required, the length of
1037 		 * this element may change. */
1038 		rdma_req->send_sgl[0].addr = (uint64_t)cmd;
1039 		rdma_req->send_wr.wr_id = (uint64_t)&rdma_req->rdma_wr;
1040 		rdma_req->send_wr.next = NULL;
1041 		rdma_req->send_wr.opcode = IBV_WR_SEND;
1042 		rdma_req->send_wr.send_flags = IBV_SEND_SIGNALED;
1043 		rdma_req->send_wr.sg_list = rdma_req->send_sgl;
1044 		rdma_req->send_wr.imm_data = 0;
1045 
1046 		TAILQ_INSERT_TAIL(&rqpair->free_reqs, rdma_req, link);
1047 	}
1048 
1049 	return 0;
1050 fail:
1051 	nvme_rdma_free_reqs(rqpair);
1052 	return -ENOMEM;
1053 }
1054 
1055 static int nvme_rdma_connect(struct nvme_rdma_qpair *rqpair);
1056 
1057 static int
1058 nvme_rdma_route_resolved(struct nvme_rdma_qpair *rqpair, int ret)
1059 {
1060 	if (ret) {
1061 		SPDK_ERRLOG("RDMA route resolution error\n");
1062 		return -1;
1063 	}
1064 
1065 	ret = nvme_rdma_qpair_init(rqpair);
1066 	if (ret < 0) {
1067 		SPDK_ERRLOG("nvme_rdma_qpair_init() failed\n");
1068 		return -1;
1069 	}
1070 
1071 	return nvme_rdma_connect(rqpair);
1072 }
1073 
1074 static int
1075 nvme_rdma_addr_resolved(struct nvme_rdma_qpair *rqpair, int ret)
1076 {
1077 	if (ret) {
1078 		SPDK_ERRLOG("RDMA address resolution error\n");
1079 		return -1;
1080 	}
1081 
1082 	if (rqpair->qpair.ctrlr->opts.transport_ack_timeout != SPDK_NVME_TRANSPORT_ACK_TIMEOUT_DISABLED) {
1083 #ifdef SPDK_CONFIG_RDMA_SET_ACK_TIMEOUT
1084 		uint8_t timeout = rqpair->qpair.ctrlr->opts.transport_ack_timeout;
1085 		ret = rdma_set_option(rqpair->cm_id, RDMA_OPTION_ID,
1086 				      RDMA_OPTION_ID_ACK_TIMEOUT,
1087 				      &timeout, sizeof(timeout));
1088 		if (ret) {
1089 			SPDK_NOTICELOG("Can't apply RDMA_OPTION_ID_ACK_TIMEOUT %d, ret %d\n", timeout, ret);
1090 		}
1091 #else
1092 		SPDK_DEBUGLOG(nvme, "transport_ack_timeout is not supported\n");
1093 #endif
1094 	}
1095 
1096 	if (rqpair->qpair.ctrlr->opts.transport_tos != SPDK_NVME_TRANSPORT_TOS_DISABLED) {
1097 #ifdef SPDK_CONFIG_RDMA_SET_TOS
1098 		uint8_t tos = rqpair->qpair.ctrlr->opts.transport_tos;
1099 		ret = rdma_set_option(rqpair->cm_id, RDMA_OPTION_ID, RDMA_OPTION_ID_TOS, &tos, sizeof(tos));
1100 		if (ret) {
1101 			SPDK_NOTICELOG("Can't apply RDMA_OPTION_ID_TOS %u, ret %d\n", tos, ret);
1102 		}
1103 #else
1104 		SPDK_DEBUGLOG(nvme, "transport_tos is not supported\n");
1105 #endif
1106 	}
1107 
1108 	ret = rdma_resolve_route(rqpair->cm_id, NVME_RDMA_TIME_OUT_IN_MS);
1109 	if (ret) {
1110 		SPDK_ERRLOG("rdma_resolve_route\n");
1111 		return ret;
1112 	}
1113 
1114 	return nvme_rdma_process_event_start(rqpair, RDMA_CM_EVENT_ROUTE_RESOLVED,
1115 					     nvme_rdma_route_resolved);
1116 }
1117 
1118 static int
1119 nvme_rdma_resolve_addr(struct nvme_rdma_qpair *rqpair,
1120 		       struct sockaddr *src_addr,
1121 		       struct sockaddr *dst_addr)
1122 {
1123 	int ret;
1124 
1125 	if (src_addr) {
1126 		int reuse = 1;
1127 
1128 		ret = rdma_set_option(rqpair->cm_id, RDMA_OPTION_ID, RDMA_OPTION_ID_REUSEADDR,
1129 				      &reuse, sizeof(reuse));
1130 		if (ret) {
1131 			SPDK_NOTICELOG("Can't apply RDMA_OPTION_ID_REUSEADDR %d, ret %d\n",
1132 				       reuse, ret);
1133 			/* It is likely that rdma_resolve_addr() returns -EADDRINUSE, but
1134 			 * we may missing something. We rely on rdma_resolve_addr().
1135 			 */
1136 		}
1137 	}
1138 
1139 	ret = rdma_resolve_addr(rqpair->cm_id, src_addr, dst_addr,
1140 				NVME_RDMA_TIME_OUT_IN_MS);
1141 	if (ret) {
1142 		SPDK_ERRLOG("rdma_resolve_addr, %d\n", errno);
1143 		return ret;
1144 	}
1145 
1146 	return nvme_rdma_process_event_start(rqpair, RDMA_CM_EVENT_ADDR_RESOLVED,
1147 					     nvme_rdma_addr_resolved);
1148 }
1149 
1150 static int nvme_rdma_stale_conn_retry(struct nvme_rdma_qpair *rqpair);
1151 
1152 static int
1153 nvme_rdma_connect_established(struct nvme_rdma_qpair *rqpair, int ret)
1154 {
1155 	struct nvme_rdma_rsp_opts opts = {};
1156 
1157 	if (ret == -ESTALE) {
1158 		return nvme_rdma_stale_conn_retry(rqpair);
1159 	} else if (ret) {
1160 		SPDK_ERRLOG("RDMA connect error %d\n", ret);
1161 		return ret;
1162 	}
1163 
1164 	assert(!rqpair->mr_map);
1165 	rqpair->mr_map = spdk_rdma_create_mem_map(rqpair->rdma_qp->qp->pd, &g_nvme_hooks,
1166 			 SPDK_RDMA_MEMORY_MAP_ROLE_INITIATOR);
1167 	if (!rqpair->mr_map) {
1168 		SPDK_ERRLOG("Unable to register RDMA memory translation map\n");
1169 		return -1;
1170 	}
1171 
1172 	ret = nvme_rdma_create_reqs(rqpair);
1173 	SPDK_DEBUGLOG(nvme, "rc =%d\n", ret);
1174 	if (ret) {
1175 		SPDK_ERRLOG("Unable to create rqpair RDMA requests\n");
1176 		return -1;
1177 	}
1178 	SPDK_DEBUGLOG(nvme, "RDMA requests created\n");
1179 
1180 	if (!rqpair->srq) {
1181 		opts.num_entries = rqpair->num_entries;
1182 		opts.rqpair = rqpair;
1183 		opts.srq = NULL;
1184 		opts.mr_map = rqpair->mr_map;
1185 
1186 		assert(!rqpair->rsps);
1187 		rqpair->rsps = nvme_rdma_create_rsps(&opts);
1188 		if (!rqpair->rsps) {
1189 			SPDK_ERRLOG("Unable to create rqpair RDMA responses\n");
1190 			return -1;
1191 		}
1192 		SPDK_DEBUGLOG(nvme, "RDMA responses created\n");
1193 
1194 		ret = nvme_rdma_qpair_submit_recvs(rqpair);
1195 		SPDK_DEBUGLOG(nvme, "rc =%d\n", ret);
1196 		if (ret) {
1197 			SPDK_ERRLOG("Unable to submit rqpair RDMA responses\n");
1198 			return -1;
1199 		}
1200 		SPDK_DEBUGLOG(nvme, "RDMA responses submitted\n");
1201 	}
1202 
1203 	rqpair->state = NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_SEND;
1204 
1205 	return 0;
1206 }
1207 
1208 static int
1209 nvme_rdma_connect(struct nvme_rdma_qpair *rqpair)
1210 {
1211 	struct rdma_conn_param				param = {};
1212 	struct spdk_nvmf_rdma_request_private_data	request_data = {};
1213 	struct ibv_device_attr				attr;
1214 	int						ret;
1215 	struct spdk_nvme_ctrlr				*ctrlr;
1216 
1217 	ret = ibv_query_device(rqpair->cm_id->verbs, &attr);
1218 	if (ret != 0) {
1219 		SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
1220 		return ret;
1221 	}
1222 
1223 	param.responder_resources = attr.max_qp_rd_atom;
1224 
1225 	ctrlr = rqpair->qpair.ctrlr;
1226 	if (!ctrlr) {
1227 		return -1;
1228 	}
1229 
1230 	request_data.qid = rqpair->qpair.id;
1231 	request_data.hrqsize = rqpair->num_entries + 1;
1232 	request_data.hsqsize = rqpair->num_entries;
1233 	request_data.cntlid = ctrlr->cntlid;
1234 
1235 	param.private_data = &request_data;
1236 	param.private_data_len = sizeof(request_data);
1237 	param.retry_count = ctrlr->opts.transport_retry_count;
1238 	param.rnr_retry_count = 7;
1239 
1240 	/* Fields below are ignored by rdma cm if qpair has been
1241 	 * created using rdma cm API. */
1242 	param.srq = 0;
1243 	param.qp_num = rqpair->rdma_qp->qp->qp_num;
1244 
1245 	ret = rdma_connect(rqpair->cm_id, &param);
1246 	if (ret) {
1247 		SPDK_ERRLOG("nvme rdma connect error\n");
1248 		return ret;
1249 	}
1250 
1251 	return nvme_rdma_process_event_start(rqpair, RDMA_CM_EVENT_ESTABLISHED,
1252 					     nvme_rdma_connect_established);
1253 }
1254 
1255 static int
1256 nvme_rdma_ctrlr_connect_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
1257 {
1258 	struct sockaddr_storage dst_addr;
1259 	struct sockaddr_storage src_addr;
1260 	bool src_addr_specified;
1261 	long int port, src_port;
1262 	int rc;
1263 	struct nvme_rdma_ctrlr *rctrlr;
1264 	struct nvme_rdma_qpair *rqpair;
1265 	struct nvme_rdma_poll_group *group;
1266 	int family;
1267 
1268 	rqpair = nvme_rdma_qpair(qpair);
1269 	rctrlr = nvme_rdma_ctrlr(ctrlr);
1270 	assert(rctrlr != NULL);
1271 
1272 	switch (ctrlr->trid.adrfam) {
1273 	case SPDK_NVMF_ADRFAM_IPV4:
1274 		family = AF_INET;
1275 		break;
1276 	case SPDK_NVMF_ADRFAM_IPV6:
1277 		family = AF_INET6;
1278 		break;
1279 	default:
1280 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", ctrlr->trid.adrfam);
1281 		return -1;
1282 	}
1283 
1284 	SPDK_DEBUGLOG(nvme, "adrfam %d ai_family %d\n", ctrlr->trid.adrfam, family);
1285 
1286 	memset(&dst_addr, 0, sizeof(dst_addr));
1287 
1288 	SPDK_DEBUGLOG(nvme, "trsvcid is %s\n", ctrlr->trid.trsvcid);
1289 	rc = nvme_parse_addr(&dst_addr, family, ctrlr->trid.traddr, ctrlr->trid.trsvcid, &port);
1290 	if (rc != 0) {
1291 		SPDK_ERRLOG("dst_addr nvme_parse_addr() failed\n");
1292 		return -1;
1293 	}
1294 
1295 	if (ctrlr->opts.src_addr[0] || ctrlr->opts.src_svcid[0]) {
1296 		memset(&src_addr, 0, sizeof(src_addr));
1297 		rc = nvme_parse_addr(&src_addr, family, ctrlr->opts.src_addr, ctrlr->opts.src_svcid, &src_port);
1298 		if (rc != 0) {
1299 			SPDK_ERRLOG("src_addr nvme_parse_addr() failed\n");
1300 			return -1;
1301 		}
1302 		src_addr_specified = true;
1303 	} else {
1304 		src_addr_specified = false;
1305 	}
1306 
1307 	rc = rdma_create_id(rctrlr->cm_channel, &rqpair->cm_id, rqpair, RDMA_PS_TCP);
1308 	if (rc < 0) {
1309 		SPDK_ERRLOG("rdma_create_id() failed\n");
1310 		return -1;
1311 	}
1312 
1313 	rc = nvme_rdma_resolve_addr(rqpair,
1314 				    src_addr_specified ? (struct sockaddr *)&src_addr : NULL,
1315 				    (struct sockaddr *)&dst_addr);
1316 	if (rc < 0) {
1317 		SPDK_ERRLOG("nvme_rdma_resolve_addr() failed\n");
1318 		return -1;
1319 	}
1320 
1321 	rqpair->state = NVME_RDMA_QPAIR_STATE_INITIALIZING;
1322 
1323 	if (qpair->poll_group != NULL) {
1324 		group = nvme_rdma_poll_group(qpair->poll_group);
1325 		TAILQ_INSERT_TAIL(&group->connecting_qpairs, rqpair, link_connecting);
1326 	}
1327 
1328 	return 0;
1329 }
1330 
1331 static int
1332 nvme_rdma_stale_conn_reconnect(struct nvme_rdma_qpair *rqpair)
1333 {
1334 	struct spdk_nvme_qpair *qpair = &rqpair->qpair;
1335 
1336 	if (spdk_get_ticks() < rqpair->evt_timeout_ticks) {
1337 		return -EAGAIN;
1338 	}
1339 
1340 	return nvme_rdma_ctrlr_connect_qpair(qpair->ctrlr, qpair);
1341 }
1342 
1343 static int
1344 nvme_rdma_ctrlr_connect_qpair_poll(struct spdk_nvme_ctrlr *ctrlr,
1345 				   struct spdk_nvme_qpair *qpair)
1346 {
1347 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
1348 	int rc;
1349 
1350 	if (rqpair->in_connect_poll) {
1351 		return -EAGAIN;
1352 	}
1353 
1354 	rqpair->in_connect_poll = true;
1355 
1356 	switch (rqpair->state) {
1357 	case NVME_RDMA_QPAIR_STATE_INVALID:
1358 		rc = -EAGAIN;
1359 		break;
1360 
1361 	case NVME_RDMA_QPAIR_STATE_INITIALIZING:
1362 	case NVME_RDMA_QPAIR_STATE_EXITING:
1363 		if (!nvme_qpair_is_admin_queue(qpair)) {
1364 			nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
1365 		}
1366 
1367 		rc = nvme_rdma_process_event_poll(rqpair);
1368 
1369 		if (!nvme_qpair_is_admin_queue(qpair)) {
1370 			nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
1371 		}
1372 
1373 		if (rc == 0) {
1374 			rc = -EAGAIN;
1375 		}
1376 		rqpair->in_connect_poll = false;
1377 
1378 		return rc;
1379 
1380 	case NVME_RDMA_QPAIR_STATE_STALE_CONN:
1381 		rc = nvme_rdma_stale_conn_reconnect(rqpair);
1382 		if (rc == 0) {
1383 			rc = -EAGAIN;
1384 		}
1385 		break;
1386 	case NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_SEND:
1387 		rc = nvme_fabric_qpair_connect_async(qpair, rqpair->num_entries + 1);
1388 		if (rc == 0) {
1389 			rqpair->state = NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_POLL;
1390 			rc = -EAGAIN;
1391 		} else {
1392 			SPDK_ERRLOG("Failed to send an NVMe-oF Fabric CONNECT command\n");
1393 		}
1394 		break;
1395 	case NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_POLL:
1396 		rc = nvme_fabric_qpair_connect_poll(qpair);
1397 		if (rc == 0) {
1398 			rqpair->state = NVME_RDMA_QPAIR_STATE_RUNNING;
1399 			nvme_qpair_set_state(qpair, NVME_QPAIR_CONNECTED);
1400 		} else if (rc != -EAGAIN) {
1401 			SPDK_ERRLOG("Failed to poll NVMe-oF Fabric CONNECT command\n");
1402 		}
1403 		break;
1404 	case NVME_RDMA_QPAIR_STATE_RUNNING:
1405 		rc = 0;
1406 		break;
1407 	default:
1408 		assert(false);
1409 		rc = -EINVAL;
1410 		break;
1411 	}
1412 
1413 	rqpair->in_connect_poll = false;
1414 
1415 	return rc;
1416 }
1417 
1418 static inline int
1419 nvme_rdma_get_memory_translation(struct nvme_request *req, struct nvme_rdma_qpair *rqpair,
1420 				 struct nvme_rdma_memory_translation_ctx *_ctx)
1421 {
1422 	struct spdk_memory_domain_translation_ctx ctx;
1423 	struct spdk_memory_domain_translation_result dma_translation = {.iov_count = 0};
1424 	struct spdk_rdma_memory_translation rdma_translation;
1425 	int rc;
1426 
1427 	assert(req);
1428 	assert(rqpair);
1429 	assert(_ctx);
1430 
1431 	if (req->payload.opts && req->payload.opts->memory_domain) {
1432 		ctx.size = sizeof(struct spdk_memory_domain_translation_ctx);
1433 		ctx.rdma.ibv_qp = rqpair->rdma_qp->qp;
1434 		dma_translation.size = sizeof(struct spdk_memory_domain_translation_result);
1435 
1436 		rc = spdk_memory_domain_translate_data(req->payload.opts->memory_domain,
1437 						       req->payload.opts->memory_domain_ctx,
1438 						       rqpair->memory_domain->domain, &ctx, _ctx->addr,
1439 						       _ctx->length, &dma_translation);
1440 		if (spdk_unlikely(rc) || dma_translation.iov_count != 1) {
1441 			SPDK_ERRLOG("DMA memory translation failed, rc %d, iov count %u\n", rc, dma_translation.iov_count);
1442 			return rc;
1443 		}
1444 
1445 		_ctx->lkey = dma_translation.rdma.lkey;
1446 		_ctx->rkey = dma_translation.rdma.rkey;
1447 		_ctx->addr = dma_translation.iov.iov_base;
1448 		_ctx->length = dma_translation.iov.iov_len;
1449 	} else {
1450 		rc = spdk_rdma_get_translation(rqpair->mr_map, _ctx->addr, _ctx->length, &rdma_translation);
1451 		if (spdk_unlikely(rc)) {
1452 			SPDK_ERRLOG("RDMA memory translation failed, rc %d\n", rc);
1453 			return rc;
1454 		}
1455 		if (rdma_translation.translation_type == SPDK_RDMA_TRANSLATION_MR) {
1456 			_ctx->lkey = rdma_translation.mr_or_key.mr->lkey;
1457 			_ctx->rkey = rdma_translation.mr_or_key.mr->rkey;
1458 		} else {
1459 			_ctx->lkey = _ctx->rkey = (uint32_t)rdma_translation.mr_or_key.key;
1460 		}
1461 	}
1462 
1463 	return 0;
1464 }
1465 
1466 
1467 /*
1468  * Build SGL describing empty payload.
1469  */
1470 static int
1471 nvme_rdma_build_null_request(struct spdk_nvme_rdma_req *rdma_req)
1472 {
1473 	struct nvme_request *req = rdma_req->req;
1474 
1475 	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
1476 
1477 	/* The first element of this SGL is pointing at an
1478 	 * spdk_nvmf_cmd object. For this particular command,
1479 	 * we only need the first 64 bytes corresponding to
1480 	 * the NVMe command. */
1481 	rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd);
1482 
1483 	/* The RDMA SGL needs one element describing the NVMe command. */
1484 	rdma_req->send_wr.num_sge = 1;
1485 
1486 	req->cmd.dptr.sgl1.keyed.type = SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK;
1487 	req->cmd.dptr.sgl1.keyed.subtype = SPDK_NVME_SGL_SUBTYPE_ADDRESS;
1488 	req->cmd.dptr.sgl1.keyed.length = 0;
1489 	req->cmd.dptr.sgl1.keyed.key = 0;
1490 	req->cmd.dptr.sgl1.address = 0;
1491 
1492 	return 0;
1493 }
1494 
1495 /*
1496  * Build inline SGL describing contiguous payload buffer.
1497  */
1498 static int
1499 nvme_rdma_build_contig_inline_request(struct nvme_rdma_qpair *rqpair,
1500 				      struct spdk_nvme_rdma_req *rdma_req)
1501 {
1502 	struct nvme_request *req = rdma_req->req;
1503 	struct nvme_rdma_memory_translation_ctx ctx = {
1504 		.addr = (uint8_t *)req->payload.contig_or_cb_arg + req->payload_offset,
1505 		.length = req->payload_size
1506 	};
1507 	int rc;
1508 
1509 	assert(ctx.length != 0);
1510 	assert(nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_CONTIG);
1511 
1512 	rc = nvme_rdma_get_memory_translation(req, rqpair, &ctx);
1513 	if (spdk_unlikely(rc)) {
1514 		return -1;
1515 	}
1516 
1517 	rdma_req->send_sgl[1].lkey = ctx.lkey;
1518 
1519 	/* The first element of this SGL is pointing at an
1520 	 * spdk_nvmf_cmd object. For this particular command,
1521 	 * we only need the first 64 bytes corresponding to
1522 	 * the NVMe command. */
1523 	rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd);
1524 
1525 	rdma_req->send_sgl[1].addr = (uint64_t)ctx.addr;
1526 	rdma_req->send_sgl[1].length = (uint32_t)ctx.length;
1527 
1528 	/* The RDMA SGL contains two elements. The first describes
1529 	 * the NVMe command and the second describes the data
1530 	 * payload. */
1531 	rdma_req->send_wr.num_sge = 2;
1532 
1533 	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
1534 	req->cmd.dptr.sgl1.unkeyed.type = SPDK_NVME_SGL_TYPE_DATA_BLOCK;
1535 	req->cmd.dptr.sgl1.unkeyed.subtype = SPDK_NVME_SGL_SUBTYPE_OFFSET;
1536 	req->cmd.dptr.sgl1.unkeyed.length = (uint32_t)ctx.length;
1537 	/* Inline only supported for icdoff == 0 currently.  This function will
1538 	 * not get called for controllers with other values. */
1539 	req->cmd.dptr.sgl1.address = (uint64_t)0;
1540 
1541 	return 0;
1542 }
1543 
1544 /*
1545  * Build SGL describing contiguous payload buffer.
1546  */
1547 static int
1548 nvme_rdma_build_contig_request(struct nvme_rdma_qpair *rqpair,
1549 			       struct spdk_nvme_rdma_req *rdma_req)
1550 {
1551 	struct nvme_request *req = rdma_req->req;
1552 	struct nvme_rdma_memory_translation_ctx ctx = {
1553 		.addr = (uint8_t *)req->payload.contig_or_cb_arg + req->payload_offset,
1554 		.length = req->payload_size
1555 	};
1556 	int rc;
1557 
1558 	assert(req->payload_size != 0);
1559 	assert(nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_CONTIG);
1560 
1561 	if (spdk_unlikely(req->payload_size > NVME_RDMA_MAX_KEYED_SGL_LENGTH)) {
1562 		SPDK_ERRLOG("SGL length %u exceeds max keyed SGL block size %u\n",
1563 			    req->payload_size, NVME_RDMA_MAX_KEYED_SGL_LENGTH);
1564 		return -1;
1565 	}
1566 
1567 	rc = nvme_rdma_get_memory_translation(req, rqpair, &ctx);
1568 	if (spdk_unlikely(rc)) {
1569 		return -1;
1570 	}
1571 
1572 	req->cmd.dptr.sgl1.keyed.key = ctx.rkey;
1573 
1574 	/* The first element of this SGL is pointing at an
1575 	 * spdk_nvmf_cmd object. For this particular command,
1576 	 * we only need the first 64 bytes corresponding to
1577 	 * the NVMe command. */
1578 	rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd);
1579 
1580 	/* The RDMA SGL needs one element describing the NVMe command. */
1581 	rdma_req->send_wr.num_sge = 1;
1582 
1583 	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
1584 	req->cmd.dptr.sgl1.keyed.type = SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK;
1585 	req->cmd.dptr.sgl1.keyed.subtype = SPDK_NVME_SGL_SUBTYPE_ADDRESS;
1586 	req->cmd.dptr.sgl1.keyed.length = (uint32_t)ctx.length;
1587 	req->cmd.dptr.sgl1.address = (uint64_t)ctx.addr;
1588 
1589 	return 0;
1590 }
1591 
1592 /*
1593  * Build SGL describing scattered payload buffer.
1594  */
1595 static int
1596 nvme_rdma_build_sgl_request(struct nvme_rdma_qpair *rqpair,
1597 			    struct spdk_nvme_rdma_req *rdma_req)
1598 {
1599 	struct nvme_request *req = rdma_req->req;
1600 	struct spdk_nvmf_cmd *cmd = &rqpair->cmds[rdma_req->id];
1601 	struct nvme_rdma_memory_translation_ctx ctx;
1602 	uint32_t remaining_size;
1603 	uint32_t sge_length;
1604 	int rc, max_num_sgl, num_sgl_desc;
1605 
1606 	assert(req->payload_size != 0);
1607 	assert(nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_SGL);
1608 	assert(req->payload.reset_sgl_fn != NULL);
1609 	assert(req->payload.next_sge_fn != NULL);
1610 	req->payload.reset_sgl_fn(req->payload.contig_or_cb_arg, req->payload_offset);
1611 
1612 	max_num_sgl = req->qpair->ctrlr->max_sges;
1613 
1614 	remaining_size = req->payload_size;
1615 	num_sgl_desc = 0;
1616 	do {
1617 		rc = req->payload.next_sge_fn(req->payload.contig_or_cb_arg, &ctx.addr, &sge_length);
1618 		if (rc) {
1619 			return -1;
1620 		}
1621 
1622 		sge_length = spdk_min(remaining_size, sge_length);
1623 
1624 		if (spdk_unlikely(sge_length > NVME_RDMA_MAX_KEYED_SGL_LENGTH)) {
1625 			SPDK_ERRLOG("SGL length %u exceeds max keyed SGL block size %u\n",
1626 				    sge_length, NVME_RDMA_MAX_KEYED_SGL_LENGTH);
1627 			return -1;
1628 		}
1629 		ctx.length = sge_length;
1630 		rc = nvme_rdma_get_memory_translation(req, rqpair, &ctx);
1631 		if (spdk_unlikely(rc)) {
1632 			return -1;
1633 		}
1634 
1635 		cmd->sgl[num_sgl_desc].keyed.key = ctx.rkey;
1636 		cmd->sgl[num_sgl_desc].keyed.type = SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK;
1637 		cmd->sgl[num_sgl_desc].keyed.subtype = SPDK_NVME_SGL_SUBTYPE_ADDRESS;
1638 		cmd->sgl[num_sgl_desc].keyed.length = (uint32_t)ctx.length;
1639 		cmd->sgl[num_sgl_desc].address = (uint64_t)ctx.addr;
1640 
1641 		remaining_size -= ctx.length;
1642 		num_sgl_desc++;
1643 	} while (remaining_size > 0 && num_sgl_desc < max_num_sgl);
1644 
1645 
1646 	/* Should be impossible if we did our sgl checks properly up the stack, but do a sanity check here. */
1647 	if (remaining_size > 0) {
1648 		return -1;
1649 	}
1650 
1651 	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
1652 
1653 	/* The RDMA SGL needs one element describing some portion
1654 	 * of the spdk_nvmf_cmd structure. */
1655 	rdma_req->send_wr.num_sge = 1;
1656 
1657 	/*
1658 	 * If only one SGL descriptor is required, it can be embedded directly in the command
1659 	 * as a data block descriptor.
1660 	 */
1661 	if (num_sgl_desc == 1) {
1662 		/* The first element of this SGL is pointing at an
1663 		 * spdk_nvmf_cmd object. For this particular command,
1664 		 * we only need the first 64 bytes corresponding to
1665 		 * the NVMe command. */
1666 		rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd);
1667 
1668 		req->cmd.dptr.sgl1.keyed.type = cmd->sgl[0].keyed.type;
1669 		req->cmd.dptr.sgl1.keyed.subtype = cmd->sgl[0].keyed.subtype;
1670 		req->cmd.dptr.sgl1.keyed.length = cmd->sgl[0].keyed.length;
1671 		req->cmd.dptr.sgl1.keyed.key = cmd->sgl[0].keyed.key;
1672 		req->cmd.dptr.sgl1.address = cmd->sgl[0].address;
1673 	} else {
1674 		/*
1675 		 * Otherwise, The SGL descriptor embedded in the command must point to the list of
1676 		 * SGL descriptors used to describe the operation. In that case it is a last segment descriptor.
1677 		 */
1678 		uint32_t descriptors_size = sizeof(struct spdk_nvme_sgl_descriptor) * num_sgl_desc;
1679 
1680 		if (spdk_unlikely(descriptors_size > rqpair->qpair.ctrlr->ioccsz_bytes)) {
1681 			SPDK_ERRLOG("Size of SGL descriptors (%u) exceeds ICD (%u)\n",
1682 				    descriptors_size, rqpair->qpair.ctrlr->ioccsz_bytes);
1683 			return -1;
1684 		}
1685 		rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd) + descriptors_size;
1686 
1687 		req->cmd.dptr.sgl1.unkeyed.type = SPDK_NVME_SGL_TYPE_LAST_SEGMENT;
1688 		req->cmd.dptr.sgl1.unkeyed.subtype = SPDK_NVME_SGL_SUBTYPE_OFFSET;
1689 		req->cmd.dptr.sgl1.unkeyed.length = descriptors_size;
1690 		req->cmd.dptr.sgl1.address = (uint64_t)0;
1691 	}
1692 
1693 	return 0;
1694 }
1695 
1696 /*
1697  * Build inline SGL describing sgl payload buffer.
1698  */
1699 static int
1700 nvme_rdma_build_sgl_inline_request(struct nvme_rdma_qpair *rqpair,
1701 				   struct spdk_nvme_rdma_req *rdma_req)
1702 {
1703 	struct nvme_request *req = rdma_req->req;
1704 	struct nvme_rdma_memory_translation_ctx ctx;
1705 	uint32_t length;
1706 	int rc;
1707 
1708 	assert(req->payload_size != 0);
1709 	assert(nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_SGL);
1710 	assert(req->payload.reset_sgl_fn != NULL);
1711 	assert(req->payload.next_sge_fn != NULL);
1712 	req->payload.reset_sgl_fn(req->payload.contig_or_cb_arg, req->payload_offset);
1713 
1714 	rc = req->payload.next_sge_fn(req->payload.contig_or_cb_arg, &ctx.addr, &length);
1715 	if (rc) {
1716 		return -1;
1717 	}
1718 
1719 	if (length < req->payload_size) {
1720 		SPDK_DEBUGLOG(nvme, "Inline SGL request split so sending separately.\n");
1721 		return nvme_rdma_build_sgl_request(rqpair, rdma_req);
1722 	}
1723 
1724 	if (length > req->payload_size) {
1725 		length = req->payload_size;
1726 	}
1727 
1728 	ctx.length = length;
1729 	rc = nvme_rdma_get_memory_translation(req, rqpair, &ctx);
1730 	if (spdk_unlikely(rc)) {
1731 		return -1;
1732 	}
1733 
1734 	rdma_req->send_sgl[1].addr = (uint64_t)ctx.addr;
1735 	rdma_req->send_sgl[1].length = (uint32_t)ctx.length;
1736 	rdma_req->send_sgl[1].lkey = ctx.lkey;
1737 
1738 	rdma_req->send_wr.num_sge = 2;
1739 
1740 	/* The first element of this SGL is pointing at an
1741 	 * spdk_nvmf_cmd object. For this particular command,
1742 	 * we only need the first 64 bytes corresponding to
1743 	 * the NVMe command. */
1744 	rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd);
1745 
1746 	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
1747 	req->cmd.dptr.sgl1.unkeyed.type = SPDK_NVME_SGL_TYPE_DATA_BLOCK;
1748 	req->cmd.dptr.sgl1.unkeyed.subtype = SPDK_NVME_SGL_SUBTYPE_OFFSET;
1749 	req->cmd.dptr.sgl1.unkeyed.length = (uint32_t)ctx.length;
1750 	/* Inline only supported for icdoff == 0 currently.  This function will
1751 	 * not get called for controllers with other values. */
1752 	req->cmd.dptr.sgl1.address = (uint64_t)0;
1753 
1754 	return 0;
1755 }
1756 
1757 static int
1758 nvme_rdma_req_init(struct nvme_rdma_qpair *rqpair, struct nvme_request *req,
1759 		   struct spdk_nvme_rdma_req *rdma_req)
1760 {
1761 	struct spdk_nvme_ctrlr *ctrlr = rqpair->qpair.ctrlr;
1762 	enum nvme_payload_type payload_type;
1763 	bool icd_supported;
1764 	int rc;
1765 
1766 	assert(rdma_req->req == NULL);
1767 	rdma_req->req = req;
1768 	req->cmd.cid = rdma_req->id;
1769 	payload_type = nvme_payload_type(&req->payload);
1770 	/*
1771 	 * Check if icdoff is non zero, to avoid interop conflicts with
1772 	 * targets with non-zero icdoff.  Both SPDK and the Linux kernel
1773 	 * targets use icdoff = 0.  For targets with non-zero icdoff, we
1774 	 * will currently just not use inline data for now.
1775 	 */
1776 	icd_supported = spdk_nvme_opc_get_data_transfer(req->cmd.opc) == SPDK_NVME_DATA_HOST_TO_CONTROLLER
1777 			&& req->payload_size <= ctrlr->ioccsz_bytes && ctrlr->icdoff == 0;
1778 
1779 	if (req->payload_size == 0) {
1780 		rc = nvme_rdma_build_null_request(rdma_req);
1781 	} else if (payload_type == NVME_PAYLOAD_TYPE_CONTIG) {
1782 		if (icd_supported) {
1783 			rc = nvme_rdma_build_contig_inline_request(rqpair, rdma_req);
1784 		} else {
1785 			rc = nvme_rdma_build_contig_request(rqpair, rdma_req);
1786 		}
1787 	} else if (payload_type == NVME_PAYLOAD_TYPE_SGL) {
1788 		if (icd_supported) {
1789 			rc = nvme_rdma_build_sgl_inline_request(rqpair, rdma_req);
1790 		} else {
1791 			rc = nvme_rdma_build_sgl_request(rqpair, rdma_req);
1792 		}
1793 	} else {
1794 		rc = -1;
1795 	}
1796 
1797 	if (rc) {
1798 		rdma_req->req = NULL;
1799 		return rc;
1800 	}
1801 
1802 	memcpy(&rqpair->cmds[rdma_req->id], &req->cmd, sizeof(req->cmd));
1803 	return 0;
1804 }
1805 
1806 static struct spdk_nvme_qpair *
1807 nvme_rdma_ctrlr_create_qpair(struct spdk_nvme_ctrlr *ctrlr,
1808 			     uint16_t qid, uint32_t qsize,
1809 			     enum spdk_nvme_qprio qprio,
1810 			     uint32_t num_requests,
1811 			     bool delay_cmd_submit,
1812 			     bool async)
1813 {
1814 	struct nvme_rdma_qpair *rqpair;
1815 	struct spdk_nvme_qpair *qpair;
1816 	int rc;
1817 
1818 	if (qsize < SPDK_NVME_QUEUE_MIN_ENTRIES) {
1819 		SPDK_ERRLOG("Failed to create qpair with size %u. Minimum queue size is %d.\n",
1820 			    qsize, SPDK_NVME_QUEUE_MIN_ENTRIES);
1821 		return NULL;
1822 	}
1823 
1824 	rqpair = spdk_zmalloc(sizeof(struct nvme_rdma_qpair), 0, NULL, SPDK_ENV_SOCKET_ID_ANY,
1825 			      SPDK_MALLOC_DMA);
1826 	if (!rqpair) {
1827 		SPDK_ERRLOG("failed to get create rqpair\n");
1828 		return NULL;
1829 	}
1830 
1831 	/* Set num_entries one less than queue size. According to NVMe
1832 	 * and NVMe-oF specs we can not submit queue size requests,
1833 	 * one slot shall always remain empty.
1834 	 */
1835 	rqpair->num_entries = qsize - 1;
1836 	rqpair->delay_cmd_submit = delay_cmd_submit;
1837 	rqpair->state = NVME_RDMA_QPAIR_STATE_INVALID;
1838 	qpair = &rqpair->qpair;
1839 	rc = nvme_qpair_init(qpair, qid, ctrlr, qprio, num_requests, async);
1840 	if (rc != 0) {
1841 		spdk_free(rqpair);
1842 		return NULL;
1843 	}
1844 
1845 	return qpair;
1846 }
1847 
1848 static void
1849 nvme_rdma_qpair_destroy(struct nvme_rdma_qpair *rqpair)
1850 {
1851 	struct spdk_nvme_qpair *qpair = &rqpair->qpair;
1852 	struct nvme_rdma_ctrlr *rctrlr;
1853 	struct nvme_rdma_cm_event_entry *entry, *tmp;
1854 
1855 	spdk_rdma_free_mem_map(&rqpair->mr_map);
1856 
1857 	if (rqpair->evt) {
1858 		rdma_ack_cm_event(rqpair->evt);
1859 		rqpair->evt = NULL;
1860 	}
1861 
1862 	/*
1863 	 * This works because we have the controller lock both in
1864 	 * this function and in the function where we add new events.
1865 	 */
1866 	if (qpair->ctrlr != NULL) {
1867 		rctrlr = nvme_rdma_ctrlr(qpair->ctrlr);
1868 		STAILQ_FOREACH_SAFE(entry, &rctrlr->pending_cm_events, link, tmp) {
1869 			if (entry->evt->id->context == rqpair) {
1870 				STAILQ_REMOVE(&rctrlr->pending_cm_events, entry, nvme_rdma_cm_event_entry, link);
1871 				rdma_ack_cm_event(entry->evt);
1872 				STAILQ_INSERT_HEAD(&rctrlr->free_cm_events, entry, link);
1873 			}
1874 		}
1875 	}
1876 
1877 	if (rqpair->cm_id) {
1878 		if (rqpair->rdma_qp) {
1879 			spdk_rdma_put_pd(rqpair->rdma_qp->qp->pd);
1880 			spdk_rdma_qp_destroy(rqpair->rdma_qp);
1881 			rqpair->rdma_qp = NULL;
1882 		}
1883 	}
1884 
1885 	if (rqpair->poller) {
1886 		struct nvme_rdma_poll_group     *group;
1887 
1888 		assert(qpair->poll_group);
1889 		group = nvme_rdma_poll_group(qpair->poll_group);
1890 
1891 		nvme_rdma_poll_group_put_poller(group, rqpair->poller);
1892 
1893 		rqpair->poller = NULL;
1894 		rqpair->cq = NULL;
1895 		if (rqpair->srq) {
1896 			rqpair->srq = NULL;
1897 			rqpair->rsps = NULL;
1898 		}
1899 	} else if (rqpair->cq) {
1900 		ibv_destroy_cq(rqpair->cq);
1901 		rqpair->cq = NULL;
1902 	}
1903 
1904 	nvme_rdma_free_reqs(rqpair);
1905 	nvme_rdma_free_rsps(rqpair->rsps);
1906 	rqpair->rsps = NULL;
1907 
1908 	/* destroy cm_id last so cma device will not be freed before we destroy the cq. */
1909 	if (rqpair->cm_id) {
1910 		rdma_destroy_id(rqpair->cm_id);
1911 		rqpair->cm_id = NULL;
1912 	}
1913 }
1914 
1915 static void nvme_rdma_qpair_abort_reqs(struct spdk_nvme_qpair *qpair, uint32_t dnr);
1916 
1917 static int
1918 nvme_rdma_qpair_disconnected(struct nvme_rdma_qpair *rqpair, int ret)
1919 {
1920 	if (ret) {
1921 		SPDK_DEBUGLOG(nvme, "Target did not respond to qpair disconnect.\n");
1922 		goto quiet;
1923 	}
1924 
1925 	if (rqpair->poller == NULL) {
1926 		/* If poller is not used, cq is not shared.
1927 		 * So complete disconnecting qpair immediately.
1928 		 */
1929 		goto quiet;
1930 	}
1931 
1932 	if (rqpair->rsps == NULL) {
1933 		goto quiet;
1934 	}
1935 
1936 	if (rqpair->need_destroy ||
1937 	    (rqpair->current_num_sends != 0 ||
1938 	     (!rqpair->srq && rqpair->rsps->current_num_recvs != 0))) {
1939 		rqpair->state = NVME_RDMA_QPAIR_STATE_LINGERING;
1940 		rqpair->evt_timeout_ticks = (NVME_RDMA_DISCONNECTED_QPAIR_TIMEOUT_US * spdk_get_ticks_hz()) /
1941 					    SPDK_SEC_TO_USEC + spdk_get_ticks();
1942 
1943 		return -EAGAIN;
1944 	}
1945 
1946 quiet:
1947 	rqpair->state = NVME_RDMA_QPAIR_STATE_EXITED;
1948 
1949 	nvme_rdma_qpair_abort_reqs(&rqpair->qpair, 0);
1950 	nvme_rdma_qpair_destroy(rqpair);
1951 	nvme_transport_ctrlr_disconnect_qpair_done(&rqpair->qpair);
1952 
1953 	return 0;
1954 }
1955 
1956 static int
1957 nvme_rdma_qpair_wait_until_quiet(struct nvme_rdma_qpair *rqpair)
1958 {
1959 	if (spdk_get_ticks() < rqpair->evt_timeout_ticks &&
1960 	    (rqpair->current_num_sends != 0 ||
1961 	     (!rqpair->srq && rqpair->rsps->current_num_recvs != 0))) {
1962 		return -EAGAIN;
1963 	}
1964 
1965 	rqpair->state = NVME_RDMA_QPAIR_STATE_EXITED;
1966 
1967 	nvme_rdma_qpair_abort_reqs(&rqpair->qpair, 0);
1968 	nvme_rdma_qpair_destroy(rqpair);
1969 	nvme_transport_ctrlr_disconnect_qpair_done(&rqpair->qpair);
1970 
1971 	return 0;
1972 }
1973 
1974 static void
1975 _nvme_rdma_ctrlr_disconnect_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair,
1976 				  nvme_rdma_cm_event_cb disconnected_qpair_cb)
1977 {
1978 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
1979 	int rc;
1980 
1981 	assert(disconnected_qpair_cb != NULL);
1982 
1983 	rqpair->state = NVME_RDMA_QPAIR_STATE_EXITING;
1984 
1985 	if (rqpair->cm_id) {
1986 		if (rqpair->rdma_qp) {
1987 			rc = spdk_rdma_qp_disconnect(rqpair->rdma_qp);
1988 			if ((qpair->ctrlr != NULL) && (rc == 0)) {
1989 				rc = nvme_rdma_process_event_start(rqpair, RDMA_CM_EVENT_DISCONNECTED,
1990 								   disconnected_qpair_cb);
1991 				if (rc == 0) {
1992 					return;
1993 				}
1994 			}
1995 		}
1996 	}
1997 
1998 	disconnected_qpair_cb(rqpair, 0);
1999 }
2000 
2001 static int
2002 nvme_rdma_ctrlr_disconnect_qpair_poll(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
2003 {
2004 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
2005 	int rc;
2006 
2007 	switch (rqpair->state) {
2008 	case NVME_RDMA_QPAIR_STATE_EXITING:
2009 		if (!nvme_qpair_is_admin_queue(qpair)) {
2010 			nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
2011 		}
2012 
2013 		rc = nvme_rdma_process_event_poll(rqpair);
2014 
2015 		if (!nvme_qpair_is_admin_queue(qpair)) {
2016 			nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
2017 		}
2018 		break;
2019 
2020 	case NVME_RDMA_QPAIR_STATE_LINGERING:
2021 		rc = nvme_rdma_qpair_wait_until_quiet(rqpair);
2022 		break;
2023 	case NVME_RDMA_QPAIR_STATE_EXITED:
2024 		rc = 0;
2025 		break;
2026 
2027 	default:
2028 		assert(false);
2029 		rc = -EAGAIN;
2030 		break;
2031 	}
2032 
2033 	return rc;
2034 }
2035 
2036 static void
2037 nvme_rdma_ctrlr_disconnect_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
2038 {
2039 	int rc;
2040 
2041 	_nvme_rdma_ctrlr_disconnect_qpair(ctrlr, qpair, nvme_rdma_qpair_disconnected);
2042 
2043 	/* If the async mode is disabled, poll the qpair until it is actually disconnected.
2044 	 * It is ensured that poll_group_process_completions() calls disconnected_qpair_cb
2045 	 * for any disconnected qpair. Hence, we do not have to check if the qpair is in
2046 	 * a poll group or not.
2047 	 * At the same time, if the qpair is being destroyed, i.e. this function is called by
2048 	 * spdk_nvme_ctrlr_free_io_qpair then we need to wait until qpair is disconnected, otherwise
2049 	 * we may leak some resources.
2050 	 */
2051 	if (qpair->async && !qpair->destroy_in_progress) {
2052 		return;
2053 	}
2054 
2055 	while (1) {
2056 		rc = nvme_rdma_ctrlr_disconnect_qpair_poll(ctrlr, qpair);
2057 		if (rc != -EAGAIN) {
2058 			break;
2059 		}
2060 	}
2061 }
2062 
2063 static int
2064 nvme_rdma_stale_conn_disconnected(struct nvme_rdma_qpair *rqpair, int ret)
2065 {
2066 	struct spdk_nvme_qpair *qpair = &rqpair->qpair;
2067 
2068 	if (ret) {
2069 		SPDK_DEBUGLOG(nvme, "Target did not respond to qpair disconnect.\n");
2070 	}
2071 
2072 	nvme_rdma_qpair_destroy(rqpair);
2073 
2074 	qpair->last_transport_failure_reason = qpair->transport_failure_reason;
2075 	qpair->transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_NONE;
2076 
2077 	rqpair->state = NVME_RDMA_QPAIR_STATE_STALE_CONN;
2078 	rqpair->evt_timeout_ticks = (NVME_RDMA_STALE_CONN_RETRY_DELAY_US * spdk_get_ticks_hz()) /
2079 				    SPDK_SEC_TO_USEC + spdk_get_ticks();
2080 
2081 	return 0;
2082 }
2083 
2084 static int
2085 nvme_rdma_stale_conn_retry(struct nvme_rdma_qpair *rqpair)
2086 {
2087 	struct spdk_nvme_qpair *qpair = &rqpair->qpair;
2088 
2089 	if (rqpair->stale_conn_retry_count >= NVME_RDMA_STALE_CONN_RETRY_MAX) {
2090 		SPDK_ERRLOG("Retry failed %d times, give up stale connection to qpair (cntlid:%u, qid:%u).\n",
2091 			    NVME_RDMA_STALE_CONN_RETRY_MAX, qpair->ctrlr->cntlid, qpair->id);
2092 		return -ESTALE;
2093 	}
2094 
2095 	rqpair->stale_conn_retry_count++;
2096 
2097 	SPDK_NOTICELOG("%d times, retry stale connection to qpair (cntlid:%u, qid:%u).\n",
2098 		       rqpair->stale_conn_retry_count, qpair->ctrlr->cntlid, qpair->id);
2099 
2100 	_nvme_rdma_ctrlr_disconnect_qpair(qpair->ctrlr, qpair, nvme_rdma_stale_conn_disconnected);
2101 
2102 	return 0;
2103 }
2104 
2105 static int
2106 nvme_rdma_ctrlr_delete_io_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
2107 {
2108 	struct nvme_rdma_qpair *rqpair;
2109 
2110 	assert(qpair != NULL);
2111 	rqpair = nvme_rdma_qpair(qpair);
2112 
2113 	if (rqpair->state != NVME_RDMA_QPAIR_STATE_EXITED) {
2114 		int rc __attribute__((unused));
2115 
2116 		/* qpair was removed from the poll group while the disconnect is not finished.
2117 		 * Destroy rdma resources forcefully. */
2118 		rc = nvme_rdma_qpair_disconnected(rqpair, 0);
2119 		assert(rc == 0);
2120 	}
2121 
2122 	nvme_rdma_qpair_abort_reqs(qpair, 0);
2123 	nvme_qpair_deinit(qpair);
2124 
2125 	nvme_rdma_put_memory_domain(rqpair->memory_domain);
2126 
2127 	spdk_free(rqpair);
2128 
2129 	return 0;
2130 }
2131 
2132 static struct spdk_nvme_qpair *
2133 nvme_rdma_ctrlr_create_io_qpair(struct spdk_nvme_ctrlr *ctrlr, uint16_t qid,
2134 				const struct spdk_nvme_io_qpair_opts *opts)
2135 {
2136 	return nvme_rdma_ctrlr_create_qpair(ctrlr, qid, opts->io_queue_size, opts->qprio,
2137 					    opts->io_queue_requests,
2138 					    opts->delay_cmd_submit,
2139 					    opts->async_mode);
2140 }
2141 
2142 static int
2143 nvme_rdma_ctrlr_enable(struct spdk_nvme_ctrlr *ctrlr)
2144 {
2145 	/* do nothing here */
2146 	return 0;
2147 }
2148 
2149 static int nvme_rdma_ctrlr_destruct(struct spdk_nvme_ctrlr *ctrlr);
2150 
2151 /* We have to use the typedef in the function declaration to appease astyle. */
2152 typedef struct spdk_nvme_ctrlr spdk_nvme_ctrlr_t;
2153 
2154 static spdk_nvme_ctrlr_t *
2155 nvme_rdma_ctrlr_construct(const struct spdk_nvme_transport_id *trid,
2156 			  const struct spdk_nvme_ctrlr_opts *opts,
2157 			  void *devhandle)
2158 {
2159 	struct nvme_rdma_ctrlr *rctrlr;
2160 	struct ibv_context **contexts;
2161 	struct ibv_device_attr dev_attr;
2162 	int i, flag, rc;
2163 
2164 	rctrlr = spdk_zmalloc(sizeof(struct nvme_rdma_ctrlr), 0, NULL, SPDK_ENV_SOCKET_ID_ANY,
2165 			      SPDK_MALLOC_DMA);
2166 	if (rctrlr == NULL) {
2167 		SPDK_ERRLOG("could not allocate ctrlr\n");
2168 		return NULL;
2169 	}
2170 
2171 	rctrlr->ctrlr.opts = *opts;
2172 	rctrlr->ctrlr.trid = *trid;
2173 
2174 	if (opts->transport_retry_count > NVME_RDMA_CTRLR_MAX_TRANSPORT_RETRY_COUNT) {
2175 		SPDK_NOTICELOG("transport_retry_count exceeds max value %d, use max value\n",
2176 			       NVME_RDMA_CTRLR_MAX_TRANSPORT_RETRY_COUNT);
2177 		rctrlr->ctrlr.opts.transport_retry_count = NVME_RDMA_CTRLR_MAX_TRANSPORT_RETRY_COUNT;
2178 	}
2179 
2180 	if (opts->transport_ack_timeout > NVME_RDMA_CTRLR_MAX_TRANSPORT_ACK_TIMEOUT) {
2181 		SPDK_NOTICELOG("transport_ack_timeout exceeds max value %d, use max value\n",
2182 			       NVME_RDMA_CTRLR_MAX_TRANSPORT_ACK_TIMEOUT);
2183 		rctrlr->ctrlr.opts.transport_ack_timeout = NVME_RDMA_CTRLR_MAX_TRANSPORT_ACK_TIMEOUT;
2184 	}
2185 
2186 	contexts = rdma_get_devices(NULL);
2187 	if (contexts == NULL) {
2188 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2189 		spdk_free(rctrlr);
2190 		return NULL;
2191 	}
2192 
2193 	i = 0;
2194 	rctrlr->max_sge = NVME_RDMA_MAX_SGL_DESCRIPTORS;
2195 
2196 	while (contexts[i] != NULL) {
2197 		rc = ibv_query_device(contexts[i], &dev_attr);
2198 		if (rc < 0) {
2199 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2200 			rdma_free_devices(contexts);
2201 			spdk_free(rctrlr);
2202 			return NULL;
2203 		}
2204 		rctrlr->max_sge = spdk_min(rctrlr->max_sge, (uint16_t)dev_attr.max_sge);
2205 		i++;
2206 	}
2207 
2208 	rdma_free_devices(contexts);
2209 
2210 	rc = nvme_ctrlr_construct(&rctrlr->ctrlr);
2211 	if (rc != 0) {
2212 		spdk_free(rctrlr);
2213 		return NULL;
2214 	}
2215 
2216 	STAILQ_INIT(&rctrlr->pending_cm_events);
2217 	STAILQ_INIT(&rctrlr->free_cm_events);
2218 	rctrlr->cm_events = spdk_zmalloc(NVME_RDMA_NUM_CM_EVENTS * sizeof(*rctrlr->cm_events), 0, NULL,
2219 					 SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
2220 	if (rctrlr->cm_events == NULL) {
2221 		SPDK_ERRLOG("unable to allocate buffers to hold CM events.\n");
2222 		goto destruct_ctrlr;
2223 	}
2224 
2225 	for (i = 0; i < NVME_RDMA_NUM_CM_EVENTS; i++) {
2226 		STAILQ_INSERT_TAIL(&rctrlr->free_cm_events, &rctrlr->cm_events[i], link);
2227 	}
2228 
2229 	rctrlr->cm_channel = rdma_create_event_channel();
2230 	if (rctrlr->cm_channel == NULL) {
2231 		SPDK_ERRLOG("rdma_create_event_channel() failed\n");
2232 		goto destruct_ctrlr;
2233 	}
2234 
2235 	flag = fcntl(rctrlr->cm_channel->fd, F_GETFL);
2236 	if (fcntl(rctrlr->cm_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2237 		SPDK_ERRLOG("Cannot set event channel to non blocking\n");
2238 		goto destruct_ctrlr;
2239 	}
2240 
2241 	rctrlr->ctrlr.adminq = nvme_rdma_ctrlr_create_qpair(&rctrlr->ctrlr, 0,
2242 			       rctrlr->ctrlr.opts.admin_queue_size, 0,
2243 			       rctrlr->ctrlr.opts.admin_queue_size, false, true);
2244 	if (!rctrlr->ctrlr.adminq) {
2245 		SPDK_ERRLOG("failed to create admin qpair\n");
2246 		goto destruct_ctrlr;
2247 	}
2248 
2249 	if (nvme_ctrlr_add_process(&rctrlr->ctrlr, 0) != 0) {
2250 		SPDK_ERRLOG("nvme_ctrlr_add_process() failed\n");
2251 		goto destruct_ctrlr;
2252 	}
2253 
2254 	SPDK_DEBUGLOG(nvme, "successfully initialized the nvmf ctrlr\n");
2255 	return &rctrlr->ctrlr;
2256 
2257 destruct_ctrlr:
2258 	nvme_ctrlr_destruct(&rctrlr->ctrlr);
2259 	return NULL;
2260 }
2261 
2262 static int
2263 nvme_rdma_ctrlr_destruct(struct spdk_nvme_ctrlr *ctrlr)
2264 {
2265 	struct nvme_rdma_ctrlr *rctrlr = nvme_rdma_ctrlr(ctrlr);
2266 	struct nvme_rdma_cm_event_entry *entry;
2267 
2268 	if (ctrlr->adminq) {
2269 		nvme_rdma_ctrlr_delete_io_qpair(ctrlr, ctrlr->adminq);
2270 	}
2271 
2272 	STAILQ_FOREACH(entry, &rctrlr->pending_cm_events, link) {
2273 		rdma_ack_cm_event(entry->evt);
2274 	}
2275 
2276 	STAILQ_INIT(&rctrlr->free_cm_events);
2277 	STAILQ_INIT(&rctrlr->pending_cm_events);
2278 	spdk_free(rctrlr->cm_events);
2279 
2280 	if (rctrlr->cm_channel) {
2281 		rdma_destroy_event_channel(rctrlr->cm_channel);
2282 		rctrlr->cm_channel = NULL;
2283 	}
2284 
2285 	nvme_ctrlr_destruct_finish(ctrlr);
2286 
2287 	spdk_free(rctrlr);
2288 
2289 	return 0;
2290 }
2291 
2292 static int
2293 nvme_rdma_qpair_submit_request(struct spdk_nvme_qpair *qpair,
2294 			       struct nvme_request *req)
2295 {
2296 	struct nvme_rdma_qpair *rqpair;
2297 	struct spdk_nvme_rdma_req *rdma_req;
2298 	struct ibv_send_wr *wr;
2299 
2300 	rqpair = nvme_rdma_qpair(qpair);
2301 	assert(rqpair != NULL);
2302 	assert(req != NULL);
2303 
2304 	rdma_req = nvme_rdma_req_get(rqpair);
2305 	if (spdk_unlikely(!rdma_req)) {
2306 		if (rqpair->poller) {
2307 			rqpair->poller->stats.queued_requests++;
2308 		}
2309 		/* Inform the upper layer to try again later. */
2310 		return -EAGAIN;
2311 	}
2312 
2313 	if (nvme_rdma_req_init(rqpair, req, rdma_req)) {
2314 		SPDK_ERRLOG("nvme_rdma_req_init() failed\n");
2315 		nvme_rdma_req_put(rqpair, rdma_req);
2316 		return -1;
2317 	}
2318 
2319 	TAILQ_INSERT_TAIL(&rqpair->outstanding_reqs, rdma_req, link);
2320 
2321 	assert(rqpair->current_num_sends < rqpair->num_entries);
2322 	rqpair->current_num_sends++;
2323 
2324 	wr = &rdma_req->send_wr;
2325 	wr->next = NULL;
2326 	nvme_rdma_trace_ibv_sge(wr->sg_list);
2327 
2328 	spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, wr);
2329 
2330 	if (!rqpair->delay_cmd_submit) {
2331 		return nvme_rdma_qpair_submit_sends(rqpair);
2332 	}
2333 
2334 	return 0;
2335 }
2336 
2337 static int
2338 nvme_rdma_qpair_reset(struct spdk_nvme_qpair *qpair)
2339 {
2340 	/* Currently, doing nothing here */
2341 	return 0;
2342 }
2343 
2344 static void
2345 nvme_rdma_qpair_abort_reqs(struct spdk_nvme_qpair *qpair, uint32_t dnr)
2346 {
2347 	struct spdk_nvme_rdma_req *rdma_req, *tmp;
2348 	struct spdk_nvme_cpl cpl;
2349 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
2350 
2351 	cpl.sqid = qpair->id;
2352 	cpl.status.sc = SPDK_NVME_SC_ABORTED_SQ_DELETION;
2353 	cpl.status.sct = SPDK_NVME_SCT_GENERIC;
2354 	cpl.status.dnr = dnr;
2355 
2356 	/*
2357 	 * We cannot abort requests at the RDMA layer without
2358 	 * unregistering them. If we do, we can still get error
2359 	 * free completions on the shared completion queue.
2360 	 */
2361 	if (nvme_qpair_get_state(qpair) > NVME_QPAIR_DISCONNECTING &&
2362 	    nvme_qpair_get_state(qpair) != NVME_QPAIR_DESTROYING) {
2363 		nvme_ctrlr_disconnect_qpair(qpair);
2364 	}
2365 
2366 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->outstanding_reqs, link, tmp) {
2367 		nvme_rdma_req_complete(rdma_req, &cpl, true);
2368 	}
2369 }
2370 
2371 static void
2372 nvme_rdma_qpair_check_timeout(struct spdk_nvme_qpair *qpair)
2373 {
2374 	uint64_t t02;
2375 	struct spdk_nvme_rdma_req *rdma_req, *tmp;
2376 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
2377 	struct spdk_nvme_ctrlr *ctrlr = qpair->ctrlr;
2378 	struct spdk_nvme_ctrlr_process *active_proc;
2379 
2380 	/* Don't check timeouts during controller initialization. */
2381 	if (ctrlr->state != NVME_CTRLR_STATE_READY) {
2382 		return;
2383 	}
2384 
2385 	if (nvme_qpair_is_admin_queue(qpair)) {
2386 		active_proc = nvme_ctrlr_get_current_process(ctrlr);
2387 	} else {
2388 		active_proc = qpair->active_proc;
2389 	}
2390 
2391 	/* Only check timeouts if the current process has a timeout callback. */
2392 	if (active_proc == NULL || active_proc->timeout_cb_fn == NULL) {
2393 		return;
2394 	}
2395 
2396 	t02 = spdk_get_ticks();
2397 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->outstanding_reqs, link, tmp) {
2398 		assert(rdma_req->req != NULL);
2399 
2400 		if (nvme_request_check_timeout(rdma_req->req, rdma_req->id, active_proc, t02)) {
2401 			/*
2402 			 * The requests are in order, so as soon as one has not timed out,
2403 			 * stop iterating.
2404 			 */
2405 			break;
2406 		}
2407 	}
2408 }
2409 
2410 static inline void
2411 nvme_rdma_request_ready(struct nvme_rdma_qpair *rqpair, struct spdk_nvme_rdma_req *rdma_req)
2412 {
2413 	struct spdk_nvme_rdma_rsp *rdma_rsp = rdma_req->rdma_rsp;
2414 	struct ibv_recv_wr *recv_wr = rdma_rsp->recv_wr;
2415 
2416 	nvme_rdma_req_complete(rdma_req, &rdma_rsp->cpl, true);
2417 
2418 	assert(rqpair->rsps->current_num_recvs < rqpair->rsps->num_entries);
2419 	rqpair->rsps->current_num_recvs++;
2420 
2421 	recv_wr->next = NULL;
2422 	nvme_rdma_trace_ibv_sge(recv_wr->sg_list);
2423 
2424 	if (!rqpair->srq) {
2425 		spdk_rdma_qp_queue_recv_wrs(rqpair->rdma_qp, recv_wr);
2426 	} else {
2427 		spdk_rdma_srq_queue_recv_wrs(rqpair->srq, recv_wr);
2428 	}
2429 }
2430 
2431 #define MAX_COMPLETIONS_PER_POLL 128
2432 
2433 static void
2434 nvme_rdma_fail_qpair(struct spdk_nvme_qpair *qpair, int failure_reason)
2435 {
2436 	if (failure_reason == IBV_WC_RETRY_EXC_ERR) {
2437 		qpair->transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_REMOTE;
2438 	} else if (qpair->transport_failure_reason == SPDK_NVME_QPAIR_FAILURE_NONE) {
2439 		qpair->transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_UNKNOWN;
2440 	}
2441 
2442 	nvme_ctrlr_disconnect_qpair(qpair);
2443 }
2444 
2445 static struct nvme_rdma_qpair *
2446 get_rdma_qpair_from_wc(struct nvme_rdma_poll_group *group, struct ibv_wc *wc)
2447 {
2448 	struct spdk_nvme_qpair *qpair;
2449 	struct nvme_rdma_qpair *rqpair;
2450 
2451 	STAILQ_FOREACH(qpair, &group->group.connected_qpairs, poll_group_stailq) {
2452 		rqpair = nvme_rdma_qpair(qpair);
2453 		if (NVME_RDMA_POLL_GROUP_CHECK_QPN(rqpair, wc->qp_num)) {
2454 			return rqpair;
2455 		}
2456 	}
2457 
2458 	STAILQ_FOREACH(qpair, &group->group.disconnected_qpairs, poll_group_stailq) {
2459 		rqpair = nvme_rdma_qpair(qpair);
2460 		if (NVME_RDMA_POLL_GROUP_CHECK_QPN(rqpair, wc->qp_num)) {
2461 			return rqpair;
2462 		}
2463 	}
2464 
2465 	return NULL;
2466 }
2467 
2468 static inline void
2469 nvme_rdma_log_wc_status(struct nvme_rdma_qpair *rqpair, struct ibv_wc *wc)
2470 {
2471 	struct nvme_rdma_wr *rdma_wr = (struct nvme_rdma_wr *)wc->wr_id;
2472 
2473 	if (wc->status == IBV_WC_WR_FLUSH_ERR) {
2474 		/* If qpair is in ERR state, we will receive completions for all posted and not completed
2475 		 * Work Requests with IBV_WC_WR_FLUSH_ERR status. Don't log an error in that case */
2476 		SPDK_DEBUGLOG(nvme, "WC error, qid %u, qp state %d, request 0x%lu type %d, status: (%d): %s\n",
2477 			      rqpair->qpair.id, rqpair->qpair.state, wc->wr_id, rdma_wr->type, wc->status,
2478 			      ibv_wc_status_str(wc->status));
2479 	} else {
2480 		SPDK_ERRLOG("WC error, qid %u, qp state %d, request 0x%lu type %d, status: (%d): %s\n",
2481 			    rqpair->qpair.id, rqpair->qpair.state, wc->wr_id, rdma_wr->type, wc->status,
2482 			    ibv_wc_status_str(wc->status));
2483 	}
2484 }
2485 
2486 static inline int
2487 nvme_rdma_process_recv_completion(struct nvme_rdma_poller *poller, struct ibv_wc *wc,
2488 				  struct nvme_rdma_wr *rdma_wr)
2489 {
2490 	struct nvme_rdma_qpair		*rqpair;
2491 	struct spdk_nvme_rdma_req	*rdma_req;
2492 	struct spdk_nvme_rdma_rsp	*rdma_rsp;
2493 
2494 	rdma_rsp = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvme_rdma_rsp, rdma_wr);
2495 
2496 	if (poller && poller->srq) {
2497 		rqpair = get_rdma_qpair_from_wc(poller->group, wc);
2498 		if (spdk_unlikely(!rqpair)) {
2499 			/* Since we do not handle the LAST_WQE_REACHED event, we do not know when
2500 			 * a Receive Queue in a QP, that is associated with an SRQ, is flushed.
2501 			 * We may get a WC for a already destroyed QP.
2502 			 *
2503 			 * However, for the SRQ, this is not any error. Hence, just re-post the
2504 			 * receive request to the SRQ to reuse for other QPs, and return 0.
2505 			 */
2506 			spdk_rdma_srq_queue_recv_wrs(poller->srq, rdma_rsp->recv_wr);
2507 			return 0;
2508 		}
2509 	} else {
2510 		rqpair = rdma_rsp->rqpair;
2511 		if (spdk_unlikely(!rqpair)) {
2512 			/* TODO: Fix forceful QP destroy when it is not async mode.
2513 			 * CQ itself did not cause any error. Hence, return 0 for now.
2514 			 */
2515 			SPDK_WARNLOG("QP might be already destroyed.\n");
2516 			return 0;
2517 		}
2518 	}
2519 
2520 
2521 	assert(rqpair->rsps->current_num_recvs > 0);
2522 	rqpair->rsps->current_num_recvs--;
2523 
2524 	if (wc->status) {
2525 		nvme_rdma_log_wc_status(rqpair, wc);
2526 		goto err_wc;
2527 	}
2528 
2529 	SPDK_DEBUGLOG(nvme, "CQ recv completion\n");
2530 
2531 	if (wc->byte_len < sizeof(struct spdk_nvme_cpl)) {
2532 		SPDK_ERRLOG("recv length %u less than expected response size\n", wc->byte_len);
2533 		goto err_wc;
2534 	}
2535 	rdma_req = &rqpair->rdma_reqs[rdma_rsp->cpl.cid];
2536 	rdma_req->completion_flags |= NVME_RDMA_RECV_COMPLETED;
2537 	rdma_req->rdma_rsp = rdma_rsp;
2538 
2539 	if ((rdma_req->completion_flags & NVME_RDMA_SEND_COMPLETED) == 0) {
2540 		return 0;
2541 	}
2542 
2543 	nvme_rdma_request_ready(rqpair, rdma_req);
2544 
2545 	if (!rqpair->delay_cmd_submit) {
2546 		if (spdk_unlikely(nvme_rdma_qpair_submit_recvs(rqpair))) {
2547 			SPDK_ERRLOG("Unable to re-post rx descriptor\n");
2548 			nvme_rdma_fail_qpair(&rqpair->qpair, 0);
2549 			return -ENXIO;
2550 		}
2551 	}
2552 
2553 	rqpair->num_completions++;
2554 	return 1;
2555 
2556 err_wc:
2557 	nvme_rdma_fail_qpair(&rqpair->qpair, 0);
2558 	if (poller && poller->srq) {
2559 		spdk_rdma_srq_queue_recv_wrs(poller->srq, rdma_rsp->recv_wr);
2560 	}
2561 	return -ENXIO;
2562 }
2563 
2564 static inline int
2565 nvme_rdma_process_send_completion(struct nvme_rdma_poller *poller,
2566 				  struct nvme_rdma_qpair *rdma_qpair,
2567 				  struct ibv_wc *wc, struct nvme_rdma_wr *rdma_wr)
2568 {
2569 	struct nvme_rdma_qpair		*rqpair;
2570 	struct spdk_nvme_rdma_req	*rdma_req;
2571 
2572 	rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvme_rdma_req, rdma_wr);
2573 	rqpair = rdma_req->req ? nvme_rdma_qpair(rdma_req->req->qpair) : NULL;
2574 	if (!rqpair) {
2575 		rqpair = rdma_qpair != NULL ? rdma_qpair : get_rdma_qpair_from_wc(poller->group, wc);
2576 	}
2577 
2578 	/* If we are flushing I/O */
2579 	if (wc->status) {
2580 		if (!rqpair) {
2581 			/* When poll_group is used, several qpairs share the same CQ and it is possible to
2582 			 * receive a completion with error (e.g. IBV_WC_WR_FLUSH_ERR) for already disconnected qpair
2583 			 * That happens due to qpair is destroyed while there are submitted but not completed send/receive
2584 			 * Work Requests */
2585 			assert(poller);
2586 			return 0;
2587 		}
2588 		assert(rqpair->current_num_sends > 0);
2589 		rqpair->current_num_sends--;
2590 		nvme_rdma_log_wc_status(rqpair, wc);
2591 		nvme_rdma_fail_qpair(&rqpair->qpair, 0);
2592 		if (rdma_req->rdma_rsp && poller && poller->srq) {
2593 			spdk_rdma_srq_queue_recv_wrs(poller->srq, rdma_req->rdma_rsp->recv_wr);
2594 		}
2595 		return -ENXIO;
2596 	}
2597 
2598 	/* We do not support Soft Roce anymore. Other than Soft Roce's bug, we should not
2599 	 * receive a completion without error status after qpair is disconnected/destroyed.
2600 	 */
2601 	if (spdk_unlikely(rdma_req->req == NULL)) {
2602 		/*
2603 		 * Some infiniband drivers do not guarantee the previous assumption after we
2604 		 * received a RDMA_CM_EVENT_DEVICE_REMOVAL event.
2605 		 */
2606 		SPDK_ERRLOG("Received malformed completion: request 0x%"PRIx64" type %d\n", wc->wr_id,
2607 			    rdma_wr->type);
2608 		if (!rqpair || !rqpair->need_destroy) {
2609 			assert(0);
2610 		}
2611 		return -ENXIO;
2612 	}
2613 
2614 	rdma_req->completion_flags |= NVME_RDMA_SEND_COMPLETED;
2615 	assert(rqpair->current_num_sends > 0);
2616 	rqpair->current_num_sends--;
2617 
2618 	if ((rdma_req->completion_flags & NVME_RDMA_RECV_COMPLETED) == 0) {
2619 		return 0;
2620 	}
2621 
2622 	nvme_rdma_request_ready(rqpair, rdma_req);
2623 
2624 	if (!rqpair->delay_cmd_submit) {
2625 		if (spdk_unlikely(nvme_rdma_qpair_submit_recvs(rqpair))) {
2626 			SPDK_ERRLOG("Unable to re-post rx descriptor\n");
2627 			nvme_rdma_fail_qpair(&rqpair->qpair, 0);
2628 			return -ENXIO;
2629 		}
2630 	}
2631 
2632 	rqpair->num_completions++;
2633 	return 1;
2634 }
2635 
2636 static int
2637 nvme_rdma_cq_process_completions(struct ibv_cq *cq, uint32_t batch_size,
2638 				 struct nvme_rdma_poller *poller,
2639 				 struct nvme_rdma_qpair *rdma_qpair,
2640 				 uint64_t *rdma_completions)
2641 {
2642 	struct ibv_wc			wc[MAX_COMPLETIONS_PER_POLL];
2643 	struct nvme_rdma_wr		*rdma_wr;
2644 	uint32_t			reaped = 0;
2645 	int				completion_rc = 0;
2646 	int				rc, _rc, i;
2647 
2648 	rc = ibv_poll_cq(cq, batch_size, wc);
2649 	if (rc < 0) {
2650 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
2651 			    errno, spdk_strerror(errno));
2652 		return -ECANCELED;
2653 	} else if (rc == 0) {
2654 		return 0;
2655 	}
2656 
2657 	for (i = 0; i < rc; i++) {
2658 		rdma_wr = (struct nvme_rdma_wr *)wc[i].wr_id;
2659 		switch (rdma_wr->type) {
2660 		case RDMA_WR_TYPE_RECV:
2661 			_rc = nvme_rdma_process_recv_completion(poller, &wc[i], rdma_wr);
2662 			break;
2663 
2664 		case RDMA_WR_TYPE_SEND:
2665 			_rc = nvme_rdma_process_send_completion(poller, rdma_qpair, &wc[i], rdma_wr);
2666 			break;
2667 
2668 		default:
2669 			SPDK_ERRLOG("Received an unexpected opcode on the CQ: %d\n", rdma_wr->type);
2670 			return -ECANCELED;
2671 		}
2672 		if (spdk_likely(_rc >= 0)) {
2673 			reaped += _rc;
2674 		} else {
2675 			completion_rc = _rc;
2676 		}
2677 	}
2678 
2679 	*rdma_completions += rc;
2680 
2681 	if (completion_rc) {
2682 		return completion_rc;
2683 	}
2684 
2685 	return reaped;
2686 }
2687 
2688 static void
2689 dummy_disconnected_qpair_cb(struct spdk_nvme_qpair *qpair, void *poll_group_ctx)
2690 {
2691 
2692 }
2693 
2694 static int
2695 nvme_rdma_qpair_process_completions(struct spdk_nvme_qpair *qpair,
2696 				    uint32_t max_completions)
2697 {
2698 	struct nvme_rdma_qpair		*rqpair = nvme_rdma_qpair(qpair);
2699 	struct nvme_rdma_ctrlr		*rctrlr = nvme_rdma_ctrlr(qpair->ctrlr);
2700 	int				rc = 0, batch_size;
2701 	struct ibv_cq			*cq;
2702 	uint64_t			rdma_completions = 0;
2703 
2704 	/*
2705 	 * This is used during the connection phase. It's possible that we are still reaping error completions
2706 	 * from other qpairs so we need to call the poll group function. Also, it's more correct since the cq
2707 	 * is shared.
2708 	 */
2709 	if (qpair->poll_group != NULL) {
2710 		return spdk_nvme_poll_group_process_completions(qpair->poll_group->group, max_completions,
2711 				dummy_disconnected_qpair_cb);
2712 	}
2713 
2714 	if (max_completions == 0) {
2715 		max_completions = rqpair->num_entries;
2716 	} else {
2717 		max_completions = spdk_min(max_completions, rqpair->num_entries);
2718 	}
2719 
2720 	switch (nvme_qpair_get_state(qpair)) {
2721 	case NVME_QPAIR_CONNECTING:
2722 		rc = nvme_rdma_ctrlr_connect_qpair_poll(qpair->ctrlr, qpair);
2723 		if (rc == 0) {
2724 			/* Once the connection is completed, we can submit queued requests */
2725 			nvme_qpair_resubmit_requests(qpair, rqpair->num_entries);
2726 		} else if (rc != -EAGAIN) {
2727 			SPDK_ERRLOG("Failed to connect rqpair=%p\n", rqpair);
2728 			goto failed;
2729 		} else if (rqpair->state <= NVME_RDMA_QPAIR_STATE_INITIALIZING) {
2730 			return 0;
2731 		}
2732 		break;
2733 
2734 	case NVME_QPAIR_DISCONNECTING:
2735 		nvme_rdma_ctrlr_disconnect_qpair_poll(qpair->ctrlr, qpair);
2736 		return -ENXIO;
2737 
2738 	default:
2739 		if (nvme_qpair_is_admin_queue(qpair)) {
2740 			nvme_rdma_poll_events(rctrlr);
2741 		}
2742 		nvme_rdma_qpair_process_cm_event(rqpair);
2743 		break;
2744 	}
2745 
2746 	if (spdk_unlikely(qpair->transport_failure_reason != SPDK_NVME_QPAIR_FAILURE_NONE)) {
2747 		goto failed;
2748 	}
2749 
2750 	cq = rqpair->cq;
2751 
2752 	rqpair->num_completions = 0;
2753 	do {
2754 		batch_size = spdk_min((max_completions - rqpair->num_completions), MAX_COMPLETIONS_PER_POLL);
2755 		rc = nvme_rdma_cq_process_completions(cq, batch_size, NULL, rqpair, &rdma_completions);
2756 
2757 		if (rc == 0) {
2758 			break;
2759 			/* Handle the case where we fail to poll the cq. */
2760 		} else if (rc == -ECANCELED) {
2761 			goto failed;
2762 		} else if (rc == -ENXIO) {
2763 			return rc;
2764 		}
2765 	} while (rqpair->num_completions < max_completions);
2766 
2767 	if (spdk_unlikely(nvme_rdma_qpair_submit_sends(rqpair) ||
2768 			  nvme_rdma_qpair_submit_recvs(rqpair))) {
2769 		goto failed;
2770 	}
2771 
2772 	if (spdk_unlikely(qpair->ctrlr->timeout_enabled)) {
2773 		nvme_rdma_qpair_check_timeout(qpair);
2774 	}
2775 
2776 	return rqpair->num_completions;
2777 
2778 failed:
2779 	nvme_rdma_fail_qpair(qpair, 0);
2780 	return -ENXIO;
2781 }
2782 
2783 static uint32_t
2784 nvme_rdma_ctrlr_get_max_xfer_size(struct spdk_nvme_ctrlr *ctrlr)
2785 {
2786 	/* max_mr_size by ibv_query_device indicates the largest value that we can
2787 	 * set for a registered memory region.  It is independent from the actual
2788 	 * I/O size and is very likely to be larger than 2 MiB which is the
2789 	 * granularity we currently register memory regions.  Hence return
2790 	 * UINT32_MAX here and let the generic layer use the controller data to
2791 	 * moderate this value.
2792 	 */
2793 	return UINT32_MAX;
2794 }
2795 
2796 static uint16_t
2797 nvme_rdma_ctrlr_get_max_sges(struct spdk_nvme_ctrlr *ctrlr)
2798 {
2799 	struct nvme_rdma_ctrlr *rctrlr = nvme_rdma_ctrlr(ctrlr);
2800 	uint32_t max_sge = rctrlr->max_sge;
2801 	uint32_t max_in_capsule_sge = (ctrlr->cdata.nvmf_specific.ioccsz * 16 -
2802 				       sizeof(struct spdk_nvme_cmd)) /
2803 				      sizeof(struct spdk_nvme_sgl_descriptor);
2804 
2805 	/* Max SGE is limited by capsule size */
2806 	max_sge = spdk_min(max_sge, max_in_capsule_sge);
2807 	/* Max SGE may be limited by MSDBD */
2808 	if (ctrlr->cdata.nvmf_specific.msdbd != 0) {
2809 		max_sge = spdk_min(max_sge, ctrlr->cdata.nvmf_specific.msdbd);
2810 	}
2811 
2812 	/* Max SGE can't be less than 1 */
2813 	max_sge = spdk_max(1, max_sge);
2814 	return max_sge;
2815 }
2816 
2817 static int
2818 nvme_rdma_qpair_iterate_requests(struct spdk_nvme_qpair *qpair,
2819 				 int (*iter_fn)(struct nvme_request *req, void *arg),
2820 				 void *arg)
2821 {
2822 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
2823 	struct spdk_nvme_rdma_req *rdma_req, *tmp;
2824 	int rc;
2825 
2826 	assert(iter_fn != NULL);
2827 
2828 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->outstanding_reqs, link, tmp) {
2829 		assert(rdma_req->req != NULL);
2830 
2831 		rc = iter_fn(rdma_req->req, arg);
2832 		if (rc != 0) {
2833 			return rc;
2834 		}
2835 	}
2836 
2837 	return 0;
2838 }
2839 
2840 static void
2841 nvme_rdma_admin_qpair_abort_aers(struct spdk_nvme_qpair *qpair)
2842 {
2843 	struct spdk_nvme_rdma_req *rdma_req, *tmp;
2844 	struct spdk_nvme_cpl cpl;
2845 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
2846 
2847 	cpl.status.sc = SPDK_NVME_SC_ABORTED_SQ_DELETION;
2848 	cpl.status.sct = SPDK_NVME_SCT_GENERIC;
2849 
2850 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->outstanding_reqs, link, tmp) {
2851 		assert(rdma_req->req != NULL);
2852 
2853 		if (rdma_req->req->cmd.opc != SPDK_NVME_OPC_ASYNC_EVENT_REQUEST) {
2854 			continue;
2855 		}
2856 
2857 		nvme_rdma_req_complete(rdma_req, &cpl, false);
2858 	}
2859 }
2860 
2861 static void
2862 nvme_rdma_poller_destroy(struct nvme_rdma_poller *poller)
2863 {
2864 	if (poller->cq) {
2865 		ibv_destroy_cq(poller->cq);
2866 	}
2867 	if (poller->rsps) {
2868 		nvme_rdma_free_rsps(poller->rsps);
2869 	}
2870 	if (poller->srq) {
2871 		spdk_rdma_srq_destroy(poller->srq);
2872 	}
2873 	if (poller->mr_map) {
2874 		spdk_rdma_free_mem_map(&poller->mr_map);
2875 	}
2876 	if (poller->pd) {
2877 		spdk_rdma_put_pd(poller->pd);
2878 	}
2879 	free(poller);
2880 }
2881 
2882 static struct nvme_rdma_poller *
2883 nvme_rdma_poller_create(struct nvme_rdma_poll_group *group, struct ibv_context *ctx)
2884 {
2885 	struct nvme_rdma_poller *poller;
2886 	struct ibv_device_attr dev_attr;
2887 	struct spdk_rdma_srq_init_attr srq_init_attr = {};
2888 	struct nvme_rdma_rsp_opts opts;
2889 	int num_cqe, max_num_cqe;
2890 	int rc;
2891 
2892 	poller = calloc(1, sizeof(*poller));
2893 	if (poller == NULL) {
2894 		SPDK_ERRLOG("Unable to allocate poller.\n");
2895 		return NULL;
2896 	}
2897 
2898 	poller->group = group;
2899 	poller->device = ctx;
2900 
2901 	if (g_spdk_nvme_transport_opts.rdma_srq_size != 0) {
2902 		rc = ibv_query_device(ctx, &dev_attr);
2903 		if (rc) {
2904 			SPDK_ERRLOG("Unable to query RDMA device.\n");
2905 			goto fail;
2906 		}
2907 
2908 		poller->pd = spdk_rdma_get_pd(ctx);
2909 		if (poller->pd == NULL) {
2910 			SPDK_ERRLOG("Unable to get PD.\n");
2911 			goto fail;
2912 		}
2913 
2914 		poller->mr_map = spdk_rdma_create_mem_map(poller->pd, &g_nvme_hooks,
2915 				 SPDK_RDMA_MEMORY_MAP_ROLE_INITIATOR);
2916 		if (poller->mr_map == NULL) {
2917 			SPDK_ERRLOG("Unable to create memory map.\n");
2918 			goto fail;
2919 		}
2920 
2921 		srq_init_attr.stats = &poller->stats.rdma_stats.recv;
2922 		srq_init_attr.pd = poller->pd;
2923 		srq_init_attr.srq_init_attr.attr.max_wr = spdk_min((uint32_t)dev_attr.max_srq_wr,
2924 				g_spdk_nvme_transport_opts.rdma_srq_size);
2925 		srq_init_attr.srq_init_attr.attr.max_sge = spdk_min(dev_attr.max_sge,
2926 				NVME_RDMA_DEFAULT_RX_SGE);
2927 
2928 		poller->srq = spdk_rdma_srq_create(&srq_init_attr);
2929 		if (poller->srq == NULL) {
2930 			SPDK_ERRLOG("Unable to create SRQ.\n");
2931 			goto fail;
2932 		}
2933 
2934 		opts.num_entries = g_spdk_nvme_transport_opts.rdma_srq_size;
2935 		opts.rqpair = NULL;
2936 		opts.srq = poller->srq;
2937 		opts.mr_map = poller->mr_map;
2938 
2939 		poller->rsps = nvme_rdma_create_rsps(&opts);
2940 		if (poller->rsps == NULL) {
2941 			SPDK_ERRLOG("Unable to create poller RDMA responses.\n");
2942 			goto fail;
2943 		}
2944 
2945 		rc = nvme_rdma_poller_submit_recvs(poller);
2946 		if (rc) {
2947 			SPDK_ERRLOG("Unable to submit poller RDMA responses.\n");
2948 			goto fail;
2949 		}
2950 
2951 		/*
2952 		 * When using an srq, fix the size of the completion queue at startup.
2953 		 * The initiator sends only send and recv WRs. Hence, the multiplier is 2.
2954 		 * (The target sends also data WRs. Hence, the multiplier is 3.)
2955 		 */
2956 		num_cqe = g_spdk_nvme_transport_opts.rdma_srq_size * 2;
2957 	} else {
2958 		num_cqe = DEFAULT_NVME_RDMA_CQ_SIZE;
2959 	}
2960 
2961 	max_num_cqe = g_spdk_nvme_transport_opts.rdma_max_cq_size;
2962 	if (max_num_cqe != 0 && num_cqe > max_num_cqe) {
2963 		num_cqe = max_num_cqe;
2964 	}
2965 
2966 	poller->cq = ibv_create_cq(poller->device, num_cqe, group, NULL, 0);
2967 
2968 	if (poller->cq == NULL) {
2969 		SPDK_ERRLOG("Unable to create CQ, errno %d.\n", errno);
2970 		goto fail;
2971 	}
2972 
2973 	STAILQ_INSERT_HEAD(&group->pollers, poller, link);
2974 	group->num_pollers++;
2975 	poller->current_num_wc = num_cqe;
2976 	poller->required_num_wc = 0;
2977 	return poller;
2978 
2979 fail:
2980 	nvme_rdma_poller_destroy(poller);
2981 	return NULL;
2982 }
2983 
2984 static void
2985 nvme_rdma_poll_group_free_pollers(struct nvme_rdma_poll_group *group)
2986 {
2987 	struct nvme_rdma_poller	*poller, *tmp_poller;
2988 
2989 	STAILQ_FOREACH_SAFE(poller, &group->pollers, link, tmp_poller) {
2990 		assert(poller->refcnt == 0);
2991 		if (poller->refcnt) {
2992 			SPDK_WARNLOG("Destroying poller with non-zero ref count: poller %p, refcnt %d\n",
2993 				     poller, poller->refcnt);
2994 		}
2995 
2996 		STAILQ_REMOVE(&group->pollers, poller, nvme_rdma_poller, link);
2997 		nvme_rdma_poller_destroy(poller);
2998 	}
2999 }
3000 
3001 static struct nvme_rdma_poller *
3002 nvme_rdma_poll_group_get_poller(struct nvme_rdma_poll_group *group, struct ibv_context *device)
3003 {
3004 	struct nvme_rdma_poller *poller = NULL;
3005 
3006 	STAILQ_FOREACH(poller, &group->pollers, link) {
3007 		if (poller->device == device) {
3008 			break;
3009 		}
3010 	}
3011 
3012 	if (!poller) {
3013 		poller = nvme_rdma_poller_create(group, device);
3014 		if (!poller) {
3015 			SPDK_ERRLOG("Failed to create a poller for device %p\n", device);
3016 			return NULL;
3017 		}
3018 	}
3019 
3020 	poller->refcnt++;
3021 	return poller;
3022 }
3023 
3024 static void
3025 nvme_rdma_poll_group_put_poller(struct nvme_rdma_poll_group *group, struct nvme_rdma_poller *poller)
3026 {
3027 	assert(poller->refcnt > 0);
3028 	if (--poller->refcnt == 0) {
3029 		STAILQ_REMOVE(&group->pollers, poller, nvme_rdma_poller, link);
3030 		group->num_pollers--;
3031 		nvme_rdma_poller_destroy(poller);
3032 	}
3033 }
3034 
3035 static struct spdk_nvme_transport_poll_group *
3036 nvme_rdma_poll_group_create(void)
3037 {
3038 	struct nvme_rdma_poll_group	*group;
3039 
3040 	group = calloc(1, sizeof(*group));
3041 	if (group == NULL) {
3042 		SPDK_ERRLOG("Unable to allocate poll group.\n");
3043 		return NULL;
3044 	}
3045 
3046 	STAILQ_INIT(&group->pollers);
3047 	TAILQ_INIT(&group->connecting_qpairs);
3048 	return &group->group;
3049 }
3050 
3051 static int
3052 nvme_rdma_poll_group_connect_qpair(struct spdk_nvme_qpair *qpair)
3053 {
3054 	return 0;
3055 }
3056 
3057 static int
3058 nvme_rdma_poll_group_disconnect_qpair(struct spdk_nvme_qpair *qpair)
3059 {
3060 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
3061 	struct nvme_rdma_poll_group *group = nvme_rdma_poll_group(qpair->poll_group);;
3062 
3063 	if (rqpair->link_connecting.tqe_prev) {
3064 		TAILQ_REMOVE(&group->connecting_qpairs, rqpair, link_connecting);
3065 		/* We use prev pointer to check if qpair is in connecting list or not .
3066 		 * TAILQ_REMOVE doesn't do it. So, we do it manually.
3067 		 */
3068 		rqpair->link_connecting.tqe_prev = NULL;
3069 	}
3070 
3071 	return 0;
3072 }
3073 
3074 static int
3075 nvme_rdma_poll_group_add(struct spdk_nvme_transport_poll_group *tgroup,
3076 			 struct spdk_nvme_qpair *qpair)
3077 {
3078 	return 0;
3079 }
3080 
3081 static int
3082 nvme_rdma_poll_group_remove(struct spdk_nvme_transport_poll_group *tgroup,
3083 			    struct spdk_nvme_qpair *qpair)
3084 {
3085 	return 0;
3086 }
3087 
3088 static inline void
3089 nvme_rdma_qpair_process_submits(struct spdk_nvme_qpair *qpair)
3090 {
3091 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
3092 
3093 	if (spdk_unlikely(rqpair->state <= NVME_RDMA_QPAIR_STATE_INITIALIZING)) {
3094 		return;
3095 	}
3096 
3097 	if (spdk_unlikely(qpair->ctrlr->timeout_enabled)) {
3098 		nvme_rdma_qpair_check_timeout(qpair);
3099 	}
3100 
3101 	nvme_rdma_qpair_submit_sends(rqpair);
3102 	if (!rqpair->srq) {
3103 		nvme_rdma_qpair_submit_recvs(rqpair);
3104 	}
3105 	if (rqpair->num_completions > 0) {
3106 		nvme_qpair_resubmit_requests(qpair, rqpair->num_completions);
3107 		rqpair->num_completions = 0;
3108 	}
3109 }
3110 
3111 static int64_t
3112 nvme_rdma_poll_group_process_completions(struct spdk_nvme_transport_poll_group *tgroup,
3113 		uint32_t completions_per_qpair, spdk_nvme_disconnected_qpair_cb disconnected_qpair_cb)
3114 {
3115 	struct spdk_nvme_qpair			*qpair, *tmp_qpair;
3116 	struct nvme_rdma_qpair			*rqpair, *tmp_rqpair;
3117 	struct nvme_rdma_poll_group		*group;
3118 	struct nvme_rdma_poller			*poller;
3119 	int					batch_size, rc, rc2 = 0;
3120 	int64_t					total_completions = 0;
3121 	uint64_t				completions_allowed = 0;
3122 	uint64_t				completions_per_poller = 0;
3123 	uint64_t				poller_completions = 0;
3124 	uint64_t				rdma_completions;
3125 
3126 	if (completions_per_qpair == 0) {
3127 		completions_per_qpair = MAX_COMPLETIONS_PER_POLL;
3128 	}
3129 
3130 	group = nvme_rdma_poll_group(tgroup);
3131 
3132 	STAILQ_FOREACH_SAFE(qpair, &tgroup->disconnected_qpairs, poll_group_stailq, tmp_qpair) {
3133 		rc = nvme_rdma_ctrlr_disconnect_qpair_poll(qpair->ctrlr, qpair);
3134 		if (rc == 0) {
3135 			disconnected_qpair_cb(qpair, tgroup->group->ctx);
3136 		}
3137 	}
3138 
3139 	TAILQ_FOREACH_SAFE(rqpair, &group->connecting_qpairs, link_connecting, tmp_rqpair) {
3140 		qpair = &rqpair->qpair;
3141 
3142 		rc = nvme_rdma_ctrlr_connect_qpair_poll(qpair->ctrlr, qpair);
3143 		if (rc == 0 || rc != -EAGAIN) {
3144 			TAILQ_REMOVE(&group->connecting_qpairs, rqpair, link_connecting);
3145 			/* We use prev pointer to check if qpair is in connecting list or not.
3146 			 * TAILQ_REMOVE does not do it. So, we do it manually.
3147 			 */
3148 			rqpair->link_connecting.tqe_prev = NULL;
3149 
3150 			if (rc == 0) {
3151 				/* Once the connection is completed, we can submit queued requests */
3152 				nvme_qpair_resubmit_requests(qpair, rqpair->num_entries);
3153 			} else if (rc != -EAGAIN) {
3154 				SPDK_ERRLOG("Failed to connect rqpair=%p\n", rqpair);
3155 				nvme_rdma_fail_qpair(qpair, 0);
3156 			}
3157 		}
3158 	}
3159 
3160 	STAILQ_FOREACH_SAFE(qpair, &tgroup->connected_qpairs, poll_group_stailq, tmp_qpair) {
3161 		rqpair = nvme_rdma_qpair(qpair);
3162 
3163 		if (spdk_likely(nvme_qpair_get_state(qpair) != NVME_QPAIR_CONNECTING)) {
3164 			nvme_rdma_qpair_process_cm_event(rqpair);
3165 		}
3166 
3167 		if (spdk_unlikely(qpair->transport_failure_reason != SPDK_NVME_QPAIR_FAILURE_NONE)) {
3168 			rc2 = -ENXIO;
3169 			nvme_rdma_fail_qpair(qpair, 0);
3170 		}
3171 	}
3172 
3173 	completions_allowed = completions_per_qpair * tgroup->num_connected_qpairs;
3174 	if (group->num_pollers) {
3175 		completions_per_poller = spdk_max(completions_allowed / group->num_pollers, 1);
3176 	}
3177 
3178 	STAILQ_FOREACH(poller, &group->pollers, link) {
3179 		poller_completions = 0;
3180 		rdma_completions = 0;
3181 		do {
3182 			poller->stats.polls++;
3183 			batch_size = spdk_min((completions_per_poller - poller_completions), MAX_COMPLETIONS_PER_POLL);
3184 			rc = nvme_rdma_cq_process_completions(poller->cq, batch_size, poller, NULL, &rdma_completions);
3185 			if (rc <= 0) {
3186 				if (rc == -ECANCELED) {
3187 					return -EIO;
3188 				} else if (rc == 0) {
3189 					poller->stats.idle_polls++;
3190 				}
3191 				break;
3192 			}
3193 
3194 			poller_completions += rc;
3195 		} while (poller_completions < completions_per_poller);
3196 		total_completions += poller_completions;
3197 		poller->stats.completions += rdma_completions;
3198 		if (poller->srq) {
3199 			nvme_rdma_poller_submit_recvs(poller);
3200 		}
3201 	}
3202 
3203 	STAILQ_FOREACH_SAFE(qpair, &tgroup->connected_qpairs, poll_group_stailq, tmp_qpair) {
3204 		nvme_rdma_qpair_process_submits(qpair);
3205 	}
3206 
3207 	return rc2 != 0 ? rc2 : total_completions;
3208 }
3209 
3210 static int
3211 nvme_rdma_poll_group_destroy(struct spdk_nvme_transport_poll_group *tgroup)
3212 {
3213 	struct nvme_rdma_poll_group	*group = nvme_rdma_poll_group(tgroup);
3214 
3215 	if (!STAILQ_EMPTY(&tgroup->connected_qpairs) || !STAILQ_EMPTY(&tgroup->disconnected_qpairs)) {
3216 		return -EBUSY;
3217 	}
3218 
3219 	nvme_rdma_poll_group_free_pollers(group);
3220 	free(group);
3221 
3222 	return 0;
3223 }
3224 
3225 static int
3226 nvme_rdma_poll_group_get_stats(struct spdk_nvme_transport_poll_group *tgroup,
3227 			       struct spdk_nvme_transport_poll_group_stat **_stats)
3228 {
3229 	struct nvme_rdma_poll_group *group;
3230 	struct spdk_nvme_transport_poll_group_stat *stats;
3231 	struct spdk_nvme_rdma_device_stat *device_stat;
3232 	struct nvme_rdma_poller *poller;
3233 	uint32_t i = 0;
3234 
3235 	if (tgroup == NULL || _stats == NULL) {
3236 		SPDK_ERRLOG("Invalid stats or group pointer\n");
3237 		return -EINVAL;
3238 	}
3239 
3240 	group = nvme_rdma_poll_group(tgroup);
3241 	stats = calloc(1, sizeof(*stats));
3242 	if (!stats) {
3243 		SPDK_ERRLOG("Can't allocate memory for RDMA stats\n");
3244 		return -ENOMEM;
3245 	}
3246 	stats->trtype = SPDK_NVME_TRANSPORT_RDMA;
3247 	stats->rdma.num_devices = group->num_pollers;
3248 
3249 	if (stats->rdma.num_devices == 0) {
3250 		*_stats = stats;
3251 		return 0;
3252 	}
3253 
3254 	stats->rdma.device_stats = calloc(stats->rdma.num_devices, sizeof(*stats->rdma.device_stats));
3255 	if (!stats->rdma.device_stats) {
3256 		SPDK_ERRLOG("Can't allocate memory for RDMA device stats\n");
3257 		free(stats);
3258 		return -ENOMEM;
3259 	}
3260 
3261 	STAILQ_FOREACH(poller, &group->pollers, link) {
3262 		device_stat = &stats->rdma.device_stats[i];
3263 		device_stat->name = poller->device->device->name;
3264 		device_stat->polls = poller->stats.polls;
3265 		device_stat->idle_polls = poller->stats.idle_polls;
3266 		device_stat->completions = poller->stats.completions;
3267 		device_stat->queued_requests = poller->stats.queued_requests;
3268 		device_stat->total_send_wrs = poller->stats.rdma_stats.send.num_submitted_wrs;
3269 		device_stat->send_doorbell_updates = poller->stats.rdma_stats.send.doorbell_updates;
3270 		device_stat->total_recv_wrs = poller->stats.rdma_stats.recv.num_submitted_wrs;
3271 		device_stat->recv_doorbell_updates = poller->stats.rdma_stats.recv.doorbell_updates;
3272 		i++;
3273 	}
3274 
3275 	*_stats = stats;
3276 
3277 	return 0;
3278 }
3279 
3280 static void
3281 nvme_rdma_poll_group_free_stats(struct spdk_nvme_transport_poll_group *tgroup,
3282 				struct spdk_nvme_transport_poll_group_stat *stats)
3283 {
3284 	if (stats) {
3285 		free(stats->rdma.device_stats);
3286 	}
3287 	free(stats);
3288 }
3289 
3290 static int
3291 nvme_rdma_ctrlr_get_memory_domains(const struct spdk_nvme_ctrlr *ctrlr,
3292 				   struct spdk_memory_domain **domains, int array_size)
3293 {
3294 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(ctrlr->adminq);
3295 
3296 	if (domains && array_size > 0) {
3297 		domains[0] = rqpair->memory_domain->domain;
3298 	}
3299 
3300 	return 1;
3301 }
3302 
3303 void
3304 spdk_nvme_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
3305 {
3306 	g_nvme_hooks = *hooks;
3307 }
3308 
3309 const struct spdk_nvme_transport_ops rdma_ops = {
3310 	.name = "RDMA",
3311 	.type = SPDK_NVME_TRANSPORT_RDMA,
3312 	.ctrlr_construct = nvme_rdma_ctrlr_construct,
3313 	.ctrlr_scan = nvme_fabric_ctrlr_scan,
3314 	.ctrlr_destruct = nvme_rdma_ctrlr_destruct,
3315 	.ctrlr_enable = nvme_rdma_ctrlr_enable,
3316 
3317 	.ctrlr_set_reg_4 = nvme_fabric_ctrlr_set_reg_4,
3318 	.ctrlr_set_reg_8 = nvme_fabric_ctrlr_set_reg_8,
3319 	.ctrlr_get_reg_4 = nvme_fabric_ctrlr_get_reg_4,
3320 	.ctrlr_get_reg_8 = nvme_fabric_ctrlr_get_reg_8,
3321 	.ctrlr_set_reg_4_async = nvme_fabric_ctrlr_set_reg_4_async,
3322 	.ctrlr_set_reg_8_async = nvme_fabric_ctrlr_set_reg_8_async,
3323 	.ctrlr_get_reg_4_async = nvme_fabric_ctrlr_get_reg_4_async,
3324 	.ctrlr_get_reg_8_async = nvme_fabric_ctrlr_get_reg_8_async,
3325 
3326 	.ctrlr_get_max_xfer_size = nvme_rdma_ctrlr_get_max_xfer_size,
3327 	.ctrlr_get_max_sges = nvme_rdma_ctrlr_get_max_sges,
3328 
3329 	.ctrlr_create_io_qpair = nvme_rdma_ctrlr_create_io_qpair,
3330 	.ctrlr_delete_io_qpair = nvme_rdma_ctrlr_delete_io_qpair,
3331 	.ctrlr_connect_qpair = nvme_rdma_ctrlr_connect_qpair,
3332 	.ctrlr_disconnect_qpair = nvme_rdma_ctrlr_disconnect_qpair,
3333 
3334 	.ctrlr_get_memory_domains = nvme_rdma_ctrlr_get_memory_domains,
3335 
3336 	.qpair_abort_reqs = nvme_rdma_qpair_abort_reqs,
3337 	.qpair_reset = nvme_rdma_qpair_reset,
3338 	.qpair_submit_request = nvme_rdma_qpair_submit_request,
3339 	.qpair_process_completions = nvme_rdma_qpair_process_completions,
3340 	.qpair_iterate_requests = nvme_rdma_qpair_iterate_requests,
3341 	.admin_qpair_abort_aers = nvme_rdma_admin_qpair_abort_aers,
3342 
3343 	.poll_group_create = nvme_rdma_poll_group_create,
3344 	.poll_group_connect_qpair = nvme_rdma_poll_group_connect_qpair,
3345 	.poll_group_disconnect_qpair = nvme_rdma_poll_group_disconnect_qpair,
3346 	.poll_group_add = nvme_rdma_poll_group_add,
3347 	.poll_group_remove = nvme_rdma_poll_group_remove,
3348 	.poll_group_process_completions = nvme_rdma_poll_group_process_completions,
3349 	.poll_group_destroy = nvme_rdma_poll_group_destroy,
3350 	.poll_group_get_stats = nvme_rdma_poll_group_get_stats,
3351 	.poll_group_free_stats = nvme_rdma_poll_group_free_stats,
3352 };
3353 
3354 SPDK_NVME_TRANSPORT_REGISTER(rdma, &rdma_ops);
3355