xref: /spdk/lib/nvme/nvme_rdma.c (revision fb6c49f2f22f7df7ba2ad3cc3e774428b325f4d4)
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_provider.h"
27 #include "spdk_internal/rdma_utils.h"
28 
29 #define NVME_RDMA_TIME_OUT_IN_MS 2000
30 #define NVME_RDMA_RW_BUFFER_SIZE 131072
31 
32 /*
33  * NVME RDMA qpair Resource Defaults
34  */
35 #define NVME_RDMA_DEFAULT_TX_SGE		2
36 #define NVME_RDMA_DEFAULT_RX_SGE		1
37 
38 /* Max number of NVMe-oF SGL descriptors supported by the host */
39 #define NVME_RDMA_MAX_SGL_DESCRIPTORS		16
40 
41 /* number of STAILQ entries for holding pending RDMA CM events. */
42 #define NVME_RDMA_NUM_CM_EVENTS			256
43 
44 /* The default size for a shared rdma completion queue. */
45 #define DEFAULT_NVME_RDMA_CQ_SIZE		4096
46 
47 /*
48  * In the special case of a stale connection we don't expose a mechanism
49  * for the user to retry the connection so we need to handle it internally.
50  */
51 #define NVME_RDMA_STALE_CONN_RETRY_MAX		5
52 #define NVME_RDMA_STALE_CONN_RETRY_DELAY_US	10000
53 
54 /*
55  * Maximum value of transport_retry_count used by RDMA controller
56  */
57 #define NVME_RDMA_CTRLR_MAX_TRANSPORT_RETRY_COUNT	7
58 
59 /*
60  * Maximum value of transport_ack_timeout used by RDMA controller
61  */
62 #define NVME_RDMA_CTRLR_MAX_TRANSPORT_ACK_TIMEOUT	31
63 
64 /*
65  * Number of microseconds to wait until the lingering qpair becomes quiet.
66  */
67 #define NVME_RDMA_DISCONNECTED_QPAIR_TIMEOUT_US	1000000ull
68 
69 /*
70  * The max length of keyed SGL data block (3 bytes)
71  */
72 #define NVME_RDMA_MAX_KEYED_SGL_LENGTH ((1u << 24u) - 1)
73 
74 #define WC_PER_QPAIR(queue_depth)	(queue_depth * 2)
75 
76 #define NVME_RDMA_POLL_GROUP_CHECK_QPN(_rqpair, qpn)				\
77 	((_rqpair)->rdma_qp && (_rqpair)->rdma_qp->qp->qp_num == (qpn))	\
78 
79 enum nvme_rdma_wr_type {
80 	RDMA_WR_TYPE_RECV,
81 	RDMA_WR_TYPE_SEND,
82 };
83 
84 struct nvme_rdma_wr {
85 	/* Using this instead of the enum allows this struct to only occupy one byte. */
86 	uint8_t	type;
87 };
88 
89 struct spdk_nvmf_cmd {
90 	struct spdk_nvme_cmd cmd;
91 	struct spdk_nvme_sgl_descriptor sgl[NVME_RDMA_MAX_SGL_DESCRIPTORS];
92 };
93 
94 struct spdk_nvme_rdma_hooks g_nvme_hooks = {};
95 
96 /* STAILQ wrapper for cm events. */
97 struct nvme_rdma_cm_event_entry {
98 	struct rdma_cm_event			*evt;
99 	STAILQ_ENTRY(nvme_rdma_cm_event_entry)	link;
100 };
101 
102 /* NVMe RDMA transport extensions for spdk_nvme_ctrlr */
103 struct nvme_rdma_ctrlr {
104 	struct spdk_nvme_ctrlr			ctrlr;
105 
106 	uint16_t				max_sge;
107 
108 	struct rdma_event_channel		*cm_channel;
109 
110 	STAILQ_HEAD(, nvme_rdma_cm_event_entry)	pending_cm_events;
111 
112 	STAILQ_HEAD(, nvme_rdma_cm_event_entry)	free_cm_events;
113 
114 	struct nvme_rdma_cm_event_entry		*cm_events;
115 };
116 
117 struct nvme_rdma_poller_stats {
118 	uint64_t polls;
119 	uint64_t idle_polls;
120 	uint64_t queued_requests;
121 	uint64_t completions;
122 	struct spdk_rdma_provider_qp_stats rdma_stats;
123 };
124 
125 struct nvme_rdma_poll_group;
126 struct nvme_rdma_rsps;
127 
128 struct nvme_rdma_poller {
129 	struct ibv_context		*device;
130 	struct ibv_cq			*cq;
131 	struct spdk_rdma_provider_srq	*srq;
132 	struct nvme_rdma_rsps		*rsps;
133 	struct ibv_pd			*pd;
134 	struct spdk_rdma_utils_mem_map	*mr_map;
135 	uint32_t			refcnt;
136 	int				required_num_wc;
137 	int				current_num_wc;
138 	struct nvme_rdma_poller_stats	stats;
139 	struct nvme_rdma_poll_group	*group;
140 	STAILQ_ENTRY(nvme_rdma_poller)	link;
141 };
142 
143 struct nvme_rdma_qpair;
144 
145 struct nvme_rdma_poll_group {
146 	struct spdk_nvme_transport_poll_group		group;
147 	STAILQ_HEAD(, nvme_rdma_poller)			pollers;
148 	uint32_t					num_pollers;
149 	TAILQ_HEAD(, nvme_rdma_qpair)			connecting_qpairs;
150 	TAILQ_HEAD(, nvme_rdma_qpair)			active_qpairs;
151 };
152 
153 enum nvme_rdma_qpair_state {
154 	NVME_RDMA_QPAIR_STATE_INVALID = 0,
155 	NVME_RDMA_QPAIR_STATE_STALE_CONN,
156 	NVME_RDMA_QPAIR_STATE_INITIALIZING,
157 	NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_SEND,
158 	NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_POLL,
159 	NVME_RDMA_QPAIR_STATE_AUTHENTICATING,
160 	NVME_RDMA_QPAIR_STATE_RUNNING,
161 	NVME_RDMA_QPAIR_STATE_EXITING,
162 	NVME_RDMA_QPAIR_STATE_LINGERING,
163 	NVME_RDMA_QPAIR_STATE_EXITED,
164 };
165 
166 typedef int (*nvme_rdma_cm_event_cb)(struct nvme_rdma_qpair *rqpair, int ret);
167 
168 struct nvme_rdma_rsp_opts {
169 	uint16_t				num_entries;
170 	struct nvme_rdma_qpair			*rqpair;
171 	struct spdk_rdma_provider_srq		*srq;
172 	struct spdk_rdma_utils_mem_map		*mr_map;
173 };
174 
175 struct nvme_rdma_rsps {
176 	/* Parallel arrays of response buffers + response SGLs of size num_entries */
177 	struct ibv_sge				*rsp_sgls;
178 	struct spdk_nvme_rdma_rsp		*rsps;
179 
180 	struct ibv_recv_wr			*rsp_recv_wrs;
181 
182 	/* Count of outstanding recv objects */
183 	uint16_t				current_num_recvs;
184 
185 	uint16_t				num_entries;
186 };
187 
188 /* NVMe RDMA qpair extensions for spdk_nvme_qpair */
189 struct nvme_rdma_qpair {
190 	struct spdk_nvme_qpair			qpair;
191 
192 	struct spdk_rdma_provider_qp		*rdma_qp;
193 	struct rdma_cm_id			*cm_id;
194 	struct ibv_cq				*cq;
195 	struct spdk_rdma_provider_srq		*srq;
196 
197 	struct	spdk_nvme_rdma_req		*rdma_reqs;
198 
199 	uint32_t				max_send_sge;
200 
201 	uint32_t				max_recv_sge;
202 
203 	uint16_t				num_entries;
204 
205 	bool					delay_cmd_submit;
206 
207 	uint32_t				num_completions;
208 	uint32_t				num_outstanding_reqs;
209 
210 	struct nvme_rdma_rsps			*rsps;
211 
212 	/*
213 	 * Array of num_entries NVMe commands registered as RDMA message buffers.
214 	 * Indexed by rdma_req->id.
215 	 */
216 	struct spdk_nvmf_cmd			*cmds;
217 
218 	struct spdk_rdma_utils_mem_map		*mr_map;
219 
220 	TAILQ_HEAD(, spdk_nvme_rdma_req)	free_reqs;
221 	TAILQ_HEAD(, spdk_nvme_rdma_req)	outstanding_reqs;
222 
223 	struct spdk_memory_domain		*memory_domain;
224 
225 	/* Count of outstanding send objects */
226 	uint16_t				current_num_sends;
227 
228 	TAILQ_ENTRY(nvme_rdma_qpair)		link_active;
229 
230 	/* Placed at the end of the struct since it is not used frequently */
231 	struct rdma_cm_event			*evt;
232 	struct nvme_rdma_poller			*poller;
233 
234 	uint64_t				evt_timeout_ticks;
235 	nvme_rdma_cm_event_cb			evt_cb;
236 	enum rdma_cm_event_type			expected_evt_type;
237 
238 	enum nvme_rdma_qpair_state		state;
239 
240 	bool					in_connect_poll;
241 
242 	uint8_t					stale_conn_retry_count;
243 	bool					need_destroy;
244 
245 	TAILQ_ENTRY(nvme_rdma_qpair)		link_connecting;
246 };
247 
248 enum NVME_RDMA_COMPLETION_FLAGS {
249 	NVME_RDMA_SEND_COMPLETED = 1u << 0,
250 	NVME_RDMA_RECV_COMPLETED = 1u << 1,
251 };
252 
253 struct spdk_nvme_rdma_req {
254 	uint16_t				id;
255 	uint16_t				completion_flags: 2;
256 	uint16_t				reserved: 14;
257 	/* if completion of RDMA_RECV received before RDMA_SEND, we will complete nvme request
258 	 * during processing of RDMA_SEND. To complete the request we must know the response
259 	 * received in RDMA_RECV, so store it in this field */
260 	struct spdk_nvme_rdma_rsp		*rdma_rsp;
261 
262 	struct nvme_rdma_wr			rdma_wr;
263 
264 	struct ibv_send_wr			send_wr;
265 
266 	struct nvme_request			*req;
267 
268 	struct ibv_sge				send_sgl[NVME_RDMA_DEFAULT_TX_SGE];
269 
270 	TAILQ_ENTRY(spdk_nvme_rdma_req)		link;
271 };
272 
273 struct spdk_nvme_rdma_rsp {
274 	struct spdk_nvme_cpl	cpl;
275 	struct nvme_rdma_qpair	*rqpair;
276 	struct ibv_recv_wr	*recv_wr;
277 	struct nvme_rdma_wr	rdma_wr;
278 };
279 
280 struct nvme_rdma_memory_translation_ctx {
281 	void *addr;
282 	size_t length;
283 	uint32_t lkey;
284 	uint32_t rkey;
285 };
286 
287 static const char *rdma_cm_event_str[] = {
288 	"RDMA_CM_EVENT_ADDR_RESOLVED",
289 	"RDMA_CM_EVENT_ADDR_ERROR",
290 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
291 	"RDMA_CM_EVENT_ROUTE_ERROR",
292 	"RDMA_CM_EVENT_CONNECT_REQUEST",
293 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
294 	"RDMA_CM_EVENT_CONNECT_ERROR",
295 	"RDMA_CM_EVENT_UNREACHABLE",
296 	"RDMA_CM_EVENT_REJECTED",
297 	"RDMA_CM_EVENT_ESTABLISHED",
298 	"RDMA_CM_EVENT_DISCONNECTED",
299 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
300 	"RDMA_CM_EVENT_MULTICAST_JOIN",
301 	"RDMA_CM_EVENT_MULTICAST_ERROR",
302 	"RDMA_CM_EVENT_ADDR_CHANGE",
303 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
304 };
305 
306 static struct nvme_rdma_poller *nvme_rdma_poll_group_get_poller(struct nvme_rdma_poll_group *group,
307 		struct ibv_context *device);
308 static void nvme_rdma_poll_group_put_poller(struct nvme_rdma_poll_group *group,
309 		struct nvme_rdma_poller *poller);
310 
311 static int nvme_rdma_ctrlr_delete_io_qpair(struct spdk_nvme_ctrlr *ctrlr,
312 		struct spdk_nvme_qpair *qpair);
313 
314 static inline struct nvme_rdma_qpair *
315 nvme_rdma_qpair(struct spdk_nvme_qpair *qpair)
316 {
317 	assert(qpair->trtype == SPDK_NVME_TRANSPORT_RDMA);
318 	return SPDK_CONTAINEROF(qpair, struct nvme_rdma_qpair, qpair);
319 }
320 
321 static inline struct nvme_rdma_poll_group *
322 nvme_rdma_poll_group(struct spdk_nvme_transport_poll_group *group)
323 {
324 	return (SPDK_CONTAINEROF(group, struct nvme_rdma_poll_group, group));
325 }
326 
327 static inline struct nvme_rdma_ctrlr *
328 nvme_rdma_ctrlr(struct spdk_nvme_ctrlr *ctrlr)
329 {
330 	assert(ctrlr->trid.trtype == SPDK_NVME_TRANSPORT_RDMA);
331 	return SPDK_CONTAINEROF(ctrlr, struct nvme_rdma_ctrlr, ctrlr);
332 }
333 
334 static struct spdk_nvme_rdma_req *
335 nvme_rdma_req_get(struct nvme_rdma_qpair *rqpair)
336 {
337 	struct spdk_nvme_rdma_req *rdma_req;
338 
339 	rdma_req = TAILQ_FIRST(&rqpair->free_reqs);
340 	if (rdma_req) {
341 		TAILQ_REMOVE(&rqpair->free_reqs, rdma_req, link);
342 	}
343 
344 	return rdma_req;
345 }
346 
347 static void
348 nvme_rdma_req_put(struct nvme_rdma_qpair *rqpair, struct spdk_nvme_rdma_req *rdma_req)
349 {
350 	rdma_req->completion_flags = 0;
351 	rdma_req->req = NULL;
352 	rdma_req->rdma_rsp = NULL;
353 	TAILQ_INSERT_HEAD(&rqpair->free_reqs, rdma_req, link);
354 }
355 
356 static void
357 nvme_rdma_req_complete(struct spdk_nvme_rdma_req *rdma_req,
358 		       struct spdk_nvme_cpl *rsp,
359 		       bool print_on_error)
360 {
361 	struct nvme_request *req = rdma_req->req;
362 	struct nvme_rdma_qpair *rqpair;
363 	struct spdk_nvme_qpair *qpair;
364 	bool error, print_error;
365 
366 	assert(req != NULL);
367 
368 	qpair = req->qpair;
369 	rqpair = nvme_rdma_qpair(qpair);
370 
371 	error = spdk_nvme_cpl_is_error(rsp);
372 	print_error = error && print_on_error && !qpair->ctrlr->opts.disable_error_logging;
373 
374 	if (print_error) {
375 		spdk_nvme_qpair_print_command(qpair, &req->cmd);
376 	}
377 
378 	if (print_error || SPDK_DEBUGLOG_FLAG_ENABLED("nvme")) {
379 		spdk_nvme_qpair_print_completion(qpair, rsp);
380 	}
381 
382 	assert(rqpair->num_outstanding_reqs > 0);
383 	rqpair->num_outstanding_reqs--;
384 
385 	TAILQ_REMOVE(&rqpair->outstanding_reqs, rdma_req, link);
386 
387 	nvme_complete_request(req->cb_fn, req->cb_arg, qpair, req, rsp);
388 	nvme_rdma_req_put(rqpair, rdma_req);
389 }
390 
391 static const char *
392 nvme_rdma_cm_event_str_get(uint32_t event)
393 {
394 	if (event < SPDK_COUNTOF(rdma_cm_event_str)) {
395 		return rdma_cm_event_str[event];
396 	} else {
397 		return "Undefined";
398 	}
399 }
400 
401 
402 static int
403 nvme_rdma_qpair_process_cm_event(struct nvme_rdma_qpair *rqpair)
404 {
405 	struct rdma_cm_event				*event = rqpair->evt;
406 	struct spdk_nvmf_rdma_accept_private_data	*accept_data;
407 	int						rc = 0;
408 
409 	if (event) {
410 		switch (event->event) {
411 		case RDMA_CM_EVENT_ADDR_RESOLVED:
412 		case RDMA_CM_EVENT_ADDR_ERROR:
413 		case RDMA_CM_EVENT_ROUTE_RESOLVED:
414 		case RDMA_CM_EVENT_ROUTE_ERROR:
415 			break;
416 		case RDMA_CM_EVENT_CONNECT_REQUEST:
417 			break;
418 		case RDMA_CM_EVENT_CONNECT_ERROR:
419 			break;
420 		case RDMA_CM_EVENT_UNREACHABLE:
421 		case RDMA_CM_EVENT_REJECTED:
422 			break;
423 		case RDMA_CM_EVENT_CONNECT_RESPONSE:
424 			rc = spdk_rdma_provider_qp_complete_connect(rqpair->rdma_qp);
425 		/* fall through */
426 		case RDMA_CM_EVENT_ESTABLISHED:
427 			accept_data = (struct spdk_nvmf_rdma_accept_private_data *)event->param.conn.private_data;
428 			if (accept_data == NULL) {
429 				rc = -1;
430 			} else {
431 				SPDK_DEBUGLOG(nvme, "Requested queue depth %d. Target receive queue depth %d.\n",
432 					      rqpair->num_entries + 1, accept_data->crqsize);
433 			}
434 			break;
435 		case RDMA_CM_EVENT_DISCONNECTED:
436 			rqpair->qpair.transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_REMOTE;
437 			break;
438 		case RDMA_CM_EVENT_DEVICE_REMOVAL:
439 			rqpair->qpair.transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_LOCAL;
440 			rqpair->need_destroy = true;
441 			break;
442 		case RDMA_CM_EVENT_MULTICAST_JOIN:
443 		case RDMA_CM_EVENT_MULTICAST_ERROR:
444 			break;
445 		case RDMA_CM_EVENT_ADDR_CHANGE:
446 			rqpair->qpair.transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_LOCAL;
447 			break;
448 		case RDMA_CM_EVENT_TIMEWAIT_EXIT:
449 			break;
450 		default:
451 			SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
452 			break;
453 		}
454 		rqpair->evt = NULL;
455 		rdma_ack_cm_event(event);
456 	}
457 
458 	return rc;
459 }
460 
461 /*
462  * This function must be called under the nvme controller's lock
463  * because it touches global controller variables. The lock is taken
464  * by the generic transport code before invoking a few of the functions
465  * in this file: nvme_rdma_ctrlr_connect_qpair, nvme_rdma_ctrlr_delete_io_qpair,
466  * and conditionally nvme_rdma_qpair_process_completions when it is calling
467  * completions on the admin qpair. When adding a new call to this function, please
468  * verify that it is in a situation where it falls under the lock.
469  */
470 static int
471 nvme_rdma_poll_events(struct nvme_rdma_ctrlr *rctrlr)
472 {
473 	struct nvme_rdma_cm_event_entry	*entry, *tmp;
474 	struct nvme_rdma_qpair		*event_qpair;
475 	struct rdma_cm_event		*event;
476 	struct rdma_event_channel	*channel = rctrlr->cm_channel;
477 
478 	STAILQ_FOREACH_SAFE(entry, &rctrlr->pending_cm_events, link, tmp) {
479 		event_qpair = entry->evt->id->context;
480 		if (event_qpair->evt == NULL) {
481 			event_qpair->evt = entry->evt;
482 			STAILQ_REMOVE(&rctrlr->pending_cm_events, entry, nvme_rdma_cm_event_entry, link);
483 			STAILQ_INSERT_HEAD(&rctrlr->free_cm_events, entry, link);
484 		}
485 	}
486 
487 	while (rdma_get_cm_event(channel, &event) == 0) {
488 		event_qpair = event->id->context;
489 		if (event_qpair->evt == NULL) {
490 			event_qpair->evt = event;
491 		} else {
492 			assert(rctrlr == nvme_rdma_ctrlr(event_qpair->qpair.ctrlr));
493 			entry = STAILQ_FIRST(&rctrlr->free_cm_events);
494 			if (entry == NULL) {
495 				rdma_ack_cm_event(event);
496 				return -ENOMEM;
497 			}
498 			STAILQ_REMOVE(&rctrlr->free_cm_events, entry, nvme_rdma_cm_event_entry, link);
499 			entry->evt = event;
500 			STAILQ_INSERT_TAIL(&rctrlr->pending_cm_events, entry, link);
501 		}
502 	}
503 
504 	/* rdma_get_cm_event() returns -1 on error. If an error occurs, errno
505 	 * will be set to indicate the failure reason. So return negated errno here.
506 	 */
507 	return -errno;
508 }
509 
510 static int
511 nvme_rdma_validate_cm_event(enum rdma_cm_event_type expected_evt_type,
512 			    struct rdma_cm_event *reaped_evt)
513 {
514 	int rc = -EBADMSG;
515 
516 	if (expected_evt_type == reaped_evt->event) {
517 		return 0;
518 	}
519 
520 	switch (expected_evt_type) {
521 	case RDMA_CM_EVENT_ESTABLISHED:
522 		/*
523 		 * There is an enum ib_cm_rej_reason in the kernel headers that sets 10 as
524 		 * IB_CM_REJ_STALE_CONN. I can't find the corresponding userspace but we get
525 		 * the same values here.
526 		 */
527 		if (reaped_evt->event == RDMA_CM_EVENT_REJECTED && reaped_evt->status == 10) {
528 			rc = -ESTALE;
529 		} else if (reaped_evt->event == RDMA_CM_EVENT_CONNECT_RESPONSE) {
530 			/*
531 			 *  If we are using a qpair which is not created using rdma cm API
532 			 *  then we will receive RDMA_CM_EVENT_CONNECT_RESPONSE instead of
533 			 *  RDMA_CM_EVENT_ESTABLISHED.
534 			 */
535 			return 0;
536 		}
537 		break;
538 	default:
539 		break;
540 	}
541 
542 	SPDK_ERRLOG("Expected %s but received %s (%d) from CM event channel (status = %d)\n",
543 		    nvme_rdma_cm_event_str_get(expected_evt_type),
544 		    nvme_rdma_cm_event_str_get(reaped_evt->event), reaped_evt->event,
545 		    reaped_evt->status);
546 	return rc;
547 }
548 
549 static int
550 nvme_rdma_process_event_start(struct nvme_rdma_qpair *rqpair,
551 			      enum rdma_cm_event_type evt,
552 			      nvme_rdma_cm_event_cb evt_cb)
553 {
554 	int	rc;
555 
556 	assert(evt_cb != NULL);
557 
558 	if (rqpair->evt != NULL) {
559 		rc = nvme_rdma_qpair_process_cm_event(rqpair);
560 		if (rc) {
561 			return rc;
562 		}
563 	}
564 
565 	rqpair->expected_evt_type = evt;
566 	rqpair->evt_cb = evt_cb;
567 	rqpair->evt_timeout_ticks = (g_spdk_nvme_transport_opts.rdma_cm_event_timeout_ms * 1000 *
568 				     spdk_get_ticks_hz()) / SPDK_SEC_TO_USEC + spdk_get_ticks();
569 
570 	return 0;
571 }
572 
573 static int
574 nvme_rdma_process_event_poll(struct nvme_rdma_qpair *rqpair)
575 {
576 	struct nvme_rdma_ctrlr	*rctrlr;
577 	int	rc = 0, rc2;
578 
579 	rctrlr = nvme_rdma_ctrlr(rqpair->qpair.ctrlr);
580 	assert(rctrlr != NULL);
581 
582 	if (!rqpair->evt && spdk_get_ticks() < rqpair->evt_timeout_ticks) {
583 		rc = nvme_rdma_poll_events(rctrlr);
584 		if (rc == -EAGAIN || rc == -EWOULDBLOCK) {
585 			return rc;
586 		}
587 	}
588 
589 	if (rqpair->evt == NULL) {
590 		rc = -EADDRNOTAVAIL;
591 		goto exit;
592 	}
593 
594 	rc = nvme_rdma_validate_cm_event(rqpair->expected_evt_type, rqpair->evt);
595 
596 	rc2 = nvme_rdma_qpair_process_cm_event(rqpair);
597 	/* bad message takes precedence over the other error codes from processing the event. */
598 	rc = rc == 0 ? rc2 : rc;
599 
600 exit:
601 	assert(rqpair->evt_cb != NULL);
602 	return rqpair->evt_cb(rqpair, rc);
603 }
604 
605 static int
606 nvme_rdma_resize_cq(struct nvme_rdma_qpair *rqpair, struct nvme_rdma_poller *poller)
607 {
608 	int	current_num_wc, required_num_wc;
609 	int	max_cq_size;
610 
611 	required_num_wc = poller->required_num_wc + WC_PER_QPAIR(rqpair->num_entries);
612 	current_num_wc = poller->current_num_wc;
613 	if (current_num_wc < required_num_wc) {
614 		current_num_wc = spdk_max(current_num_wc * 2, required_num_wc);
615 	}
616 
617 	max_cq_size = g_spdk_nvme_transport_opts.rdma_max_cq_size;
618 	if (max_cq_size != 0 && current_num_wc > max_cq_size) {
619 		current_num_wc = max_cq_size;
620 	}
621 
622 	if (poller->current_num_wc != current_num_wc) {
623 		SPDK_DEBUGLOG(nvme, "Resize RDMA CQ from %d to %d\n", poller->current_num_wc,
624 			      current_num_wc);
625 		if (ibv_resize_cq(poller->cq, current_num_wc)) {
626 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
627 			return -1;
628 		}
629 
630 		poller->current_num_wc = current_num_wc;
631 	}
632 
633 	poller->required_num_wc = required_num_wc;
634 	return 0;
635 }
636 
637 static int
638 nvme_rdma_qpair_set_poller(struct spdk_nvme_qpair *qpair)
639 {
640 	struct nvme_rdma_qpair          *rqpair = nvme_rdma_qpair(qpair);
641 	struct nvme_rdma_poll_group     *group = nvme_rdma_poll_group(qpair->poll_group);
642 	struct nvme_rdma_poller         *poller;
643 
644 	assert(rqpair->cq == NULL);
645 
646 	poller = nvme_rdma_poll_group_get_poller(group, rqpair->cm_id->verbs);
647 	if (!poller) {
648 		SPDK_ERRLOG("Unable to find a cq for qpair %p on poll group %p\n", qpair, qpair->poll_group);
649 		return -EINVAL;
650 	}
651 
652 	if (!poller->srq) {
653 		if (nvme_rdma_resize_cq(rqpair, poller)) {
654 			nvme_rdma_poll_group_put_poller(group, poller);
655 			return -EPROTO;
656 		}
657 	}
658 
659 	rqpair->cq = poller->cq;
660 	rqpair->srq = poller->srq;
661 	if (rqpair->srq) {
662 		rqpair->rsps = poller->rsps;
663 	}
664 	rqpair->poller = poller;
665 	return 0;
666 }
667 
668 static int
669 nvme_rdma_qpair_init(struct nvme_rdma_qpair *rqpair)
670 {
671 	int			rc;
672 	struct spdk_rdma_provider_qp_init_attr	attr = {};
673 	struct ibv_device_attr	dev_attr;
674 	struct nvme_rdma_ctrlr	*rctrlr;
675 	uint32_t num_cqe, max_num_cqe;
676 
677 	rc = ibv_query_device(rqpair->cm_id->verbs, &dev_attr);
678 	if (rc != 0) {
679 		SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
680 		return -1;
681 	}
682 
683 	if (rqpair->qpair.poll_group) {
684 		assert(!rqpair->cq);
685 		rc = nvme_rdma_qpair_set_poller(&rqpair->qpair);
686 		if (rc) {
687 			SPDK_ERRLOG("Unable to activate the rdmaqpair.\n");
688 			return -1;
689 		}
690 		assert(rqpair->cq);
691 	} else {
692 		num_cqe = rqpair->num_entries * 2;
693 		max_num_cqe = g_spdk_nvme_transport_opts.rdma_max_cq_size;
694 		if (max_num_cqe != 0 && num_cqe > max_num_cqe) {
695 			num_cqe = max_num_cqe;
696 		}
697 		rqpair->cq = ibv_create_cq(rqpair->cm_id->verbs, num_cqe, rqpair, NULL, 0);
698 		if (!rqpair->cq) {
699 			SPDK_ERRLOG("Unable to create completion queue: errno %d: %s\n", errno, spdk_strerror(errno));
700 			return -1;
701 		}
702 	}
703 
704 	rctrlr = nvme_rdma_ctrlr(rqpair->qpair.ctrlr);
705 	if (g_nvme_hooks.get_ibv_pd) {
706 		attr.pd = g_nvme_hooks.get_ibv_pd(&rctrlr->ctrlr.trid, rqpair->cm_id->verbs);
707 	} else {
708 		attr.pd = spdk_rdma_utils_get_pd(rqpair->cm_id->verbs);
709 	}
710 
711 	attr.stats =		rqpair->poller ? &rqpair->poller->stats.rdma_stats : NULL;
712 	attr.send_cq		= rqpair->cq;
713 	attr.recv_cq		= rqpair->cq;
714 	attr.cap.max_send_wr	= rqpair->num_entries; /* SEND operations */
715 	if (rqpair->srq) {
716 		attr.srq	= rqpair->srq->srq;
717 	} else {
718 		attr.cap.max_recv_wr = rqpair->num_entries; /* RECV operations */
719 	}
720 	attr.cap.max_send_sge	= spdk_min(NVME_RDMA_DEFAULT_TX_SGE, dev_attr.max_sge);
721 	attr.cap.max_recv_sge	= spdk_min(NVME_RDMA_DEFAULT_RX_SGE, dev_attr.max_sge);
722 
723 	rqpair->rdma_qp = spdk_rdma_provider_qp_create(rqpair->cm_id, &attr);
724 
725 	if (!rqpair->rdma_qp) {
726 		return -1;
727 	}
728 
729 	rqpair->memory_domain = spdk_rdma_utils_get_memory_domain(rqpair->rdma_qp->qp->pd);
730 	if (!rqpair->memory_domain) {
731 		SPDK_ERRLOG("Failed to get memory domain\n");
732 		return -1;
733 	}
734 
735 	/* ibv_create_qp will change the values in attr.cap. Make sure we store the proper value. */
736 	rqpair->max_send_sge = spdk_min(NVME_RDMA_DEFAULT_TX_SGE, attr.cap.max_send_sge);
737 	rqpair->max_recv_sge = spdk_min(NVME_RDMA_DEFAULT_RX_SGE, attr.cap.max_recv_sge);
738 	rqpair->current_num_sends = 0;
739 
740 	rqpair->cm_id->context = rqpair;
741 
742 	return 0;
743 }
744 
745 static void
746 nvme_rdma_reset_failed_sends(struct nvme_rdma_qpair *rqpair,
747 			     struct ibv_send_wr *bad_send_wr, int rc)
748 {
749 	SPDK_ERRLOG("Failed to post WRs on send queue, errno %d (%s), bad_wr %p\n",
750 		    rc, spdk_strerror(rc), bad_send_wr);
751 	while (bad_send_wr != NULL) {
752 		assert(rqpair->current_num_sends > 0);
753 		rqpair->current_num_sends--;
754 		bad_send_wr = bad_send_wr->next;
755 	}
756 }
757 
758 static void
759 nvme_rdma_reset_failed_recvs(struct nvme_rdma_rsps *rsps,
760 			     struct ibv_recv_wr *bad_recv_wr, int rc)
761 {
762 	SPDK_ERRLOG("Failed to post WRs on receive queue, errno %d (%s), bad_wr %p\n",
763 		    rc, spdk_strerror(rc), bad_recv_wr);
764 	while (bad_recv_wr != NULL) {
765 		assert(rsps->current_num_recvs > 0);
766 		rsps->current_num_recvs--;
767 		bad_recv_wr = bad_recv_wr->next;
768 	}
769 }
770 
771 static inline int
772 nvme_rdma_qpair_submit_sends(struct nvme_rdma_qpair *rqpair)
773 {
774 	struct ibv_send_wr *bad_send_wr = NULL;
775 	int rc;
776 
777 	rc = spdk_rdma_provider_qp_flush_send_wrs(rqpair->rdma_qp, &bad_send_wr);
778 
779 	if (spdk_unlikely(rc)) {
780 		nvme_rdma_reset_failed_sends(rqpair, bad_send_wr, rc);
781 	}
782 
783 	return rc;
784 }
785 
786 static inline int
787 nvme_rdma_qpair_submit_recvs(struct nvme_rdma_qpair *rqpair)
788 {
789 	struct ibv_recv_wr *bad_recv_wr;
790 	int rc = 0;
791 
792 	rc = spdk_rdma_provider_qp_flush_recv_wrs(rqpair->rdma_qp, &bad_recv_wr);
793 	if (spdk_unlikely(rc)) {
794 		nvme_rdma_reset_failed_recvs(rqpair->rsps, bad_recv_wr, rc);
795 	}
796 
797 	return rc;
798 }
799 
800 static inline int
801 nvme_rdma_poller_submit_recvs(struct nvme_rdma_poller *poller)
802 {
803 	struct ibv_recv_wr *bad_recv_wr;
804 	int rc;
805 
806 	rc = spdk_rdma_provider_srq_flush_recv_wrs(poller->srq, &bad_recv_wr);
807 	if (spdk_unlikely(rc)) {
808 		nvme_rdma_reset_failed_recvs(poller->rsps, bad_recv_wr, rc);
809 	}
810 
811 	return rc;
812 }
813 
814 #define nvme_rdma_trace_ibv_sge(sg_list) \
815 	if (sg_list) { \
816 		SPDK_DEBUGLOG(nvme, "local addr %p length 0x%x lkey 0x%x\n", \
817 			      (void *)(sg_list)->addr, (sg_list)->length, (sg_list)->lkey); \
818 	}
819 
820 static void
821 nvme_rdma_free_rsps(struct nvme_rdma_rsps *rsps)
822 {
823 	if (!rsps) {
824 		return;
825 	}
826 
827 	spdk_free(rsps->rsps);
828 	spdk_free(rsps->rsp_sgls);
829 	spdk_free(rsps->rsp_recv_wrs);
830 	spdk_free(rsps);
831 }
832 
833 static struct nvme_rdma_rsps *
834 nvme_rdma_create_rsps(struct nvme_rdma_rsp_opts *opts)
835 {
836 	struct nvme_rdma_rsps *rsps;
837 	struct spdk_rdma_utils_memory_translation translation;
838 	uint16_t i;
839 	int rc;
840 
841 	rsps = spdk_zmalloc(sizeof(*rsps), 0, NULL, SPDK_ENV_NUMA_ID_ANY, SPDK_MALLOC_DMA);
842 	if (!rsps) {
843 		SPDK_ERRLOG("Failed to allocate rsps object\n");
844 		return NULL;
845 	}
846 
847 	rsps->rsp_sgls = spdk_zmalloc(opts->num_entries * sizeof(*rsps->rsp_sgls), 0, NULL,
848 				      SPDK_ENV_NUMA_ID_ANY, SPDK_MALLOC_DMA);
849 	if (!rsps->rsp_sgls) {
850 		SPDK_ERRLOG("Failed to allocate rsp_sgls\n");
851 		goto fail;
852 	}
853 
854 	rsps->rsp_recv_wrs = spdk_zmalloc(opts->num_entries * sizeof(*rsps->rsp_recv_wrs), 0, NULL,
855 					  SPDK_ENV_NUMA_ID_ANY, SPDK_MALLOC_DMA);
856 	if (!rsps->rsp_recv_wrs) {
857 		SPDK_ERRLOG("Failed to allocate rsp_recv_wrs\n");
858 		goto fail;
859 	}
860 
861 	rsps->rsps = spdk_zmalloc(opts->num_entries * sizeof(*rsps->rsps), 0, NULL,
862 				  SPDK_ENV_NUMA_ID_ANY, SPDK_MALLOC_DMA);
863 	if (!rsps->rsps) {
864 		SPDK_ERRLOG("can not allocate rdma rsps\n");
865 		goto fail;
866 	}
867 
868 	for (i = 0; i < opts->num_entries; i++) {
869 		struct ibv_sge *rsp_sgl = &rsps->rsp_sgls[i];
870 		struct spdk_nvme_rdma_rsp *rsp = &rsps->rsps[i];
871 		struct ibv_recv_wr *recv_wr = &rsps->rsp_recv_wrs[i];
872 
873 		rsp->rqpair = opts->rqpair;
874 		rsp->rdma_wr.type = RDMA_WR_TYPE_RECV;
875 		rsp->recv_wr = recv_wr;
876 		rsp_sgl->addr = (uint64_t)rsp;
877 		rsp_sgl->length = sizeof(struct spdk_nvme_cpl);
878 		rc = spdk_rdma_utils_get_translation(opts->mr_map, rsp, sizeof(*rsp), &translation);
879 		if (rc) {
880 			goto fail;
881 		}
882 		rsp_sgl->lkey = spdk_rdma_utils_memory_translation_get_lkey(&translation);
883 
884 		recv_wr->wr_id = (uint64_t)&rsp->rdma_wr;
885 		recv_wr->next = NULL;
886 		recv_wr->sg_list = rsp_sgl;
887 		recv_wr->num_sge = 1;
888 
889 		nvme_rdma_trace_ibv_sge(recv_wr->sg_list);
890 
891 		if (opts->rqpair) {
892 			spdk_rdma_provider_qp_queue_recv_wrs(opts->rqpair->rdma_qp, recv_wr);
893 		} else {
894 			spdk_rdma_provider_srq_queue_recv_wrs(opts->srq, recv_wr);
895 		}
896 	}
897 
898 	rsps->num_entries = opts->num_entries;
899 	rsps->current_num_recvs = opts->num_entries;
900 
901 	return rsps;
902 fail:
903 	nvme_rdma_free_rsps(rsps);
904 	return NULL;
905 }
906 
907 static void
908 nvme_rdma_free_reqs(struct nvme_rdma_qpair *rqpair)
909 {
910 	if (!rqpair->rdma_reqs) {
911 		return;
912 	}
913 
914 	spdk_free(rqpair->cmds);
915 	rqpair->cmds = NULL;
916 
917 	spdk_free(rqpair->rdma_reqs);
918 	rqpair->rdma_reqs = NULL;
919 }
920 
921 static int
922 nvme_rdma_create_reqs(struct nvme_rdma_qpair *rqpair)
923 {
924 	struct spdk_rdma_utils_memory_translation translation;
925 	uint16_t i;
926 	int rc;
927 
928 	assert(!rqpair->rdma_reqs);
929 	rqpair->rdma_reqs = spdk_zmalloc(rqpair->num_entries * sizeof(struct spdk_nvme_rdma_req), 0, NULL,
930 					 SPDK_ENV_NUMA_ID_ANY, SPDK_MALLOC_DMA);
931 	if (rqpair->rdma_reqs == NULL) {
932 		SPDK_ERRLOG("Failed to allocate rdma_reqs\n");
933 		goto fail;
934 	}
935 
936 	assert(!rqpair->cmds);
937 	rqpair->cmds = spdk_zmalloc(rqpair->num_entries * sizeof(*rqpair->cmds), 0, NULL,
938 				    SPDK_ENV_NUMA_ID_ANY, SPDK_MALLOC_DMA);
939 	if (!rqpair->cmds) {
940 		SPDK_ERRLOG("Failed to allocate RDMA cmds\n");
941 		goto fail;
942 	}
943 
944 	TAILQ_INIT(&rqpair->free_reqs);
945 	TAILQ_INIT(&rqpair->outstanding_reqs);
946 	for (i = 0; i < rqpair->num_entries; i++) {
947 		struct spdk_nvme_rdma_req	*rdma_req;
948 		struct spdk_nvmf_cmd		*cmd;
949 
950 		rdma_req = &rqpair->rdma_reqs[i];
951 		rdma_req->rdma_wr.type = RDMA_WR_TYPE_SEND;
952 		cmd = &rqpair->cmds[i];
953 
954 		rdma_req->id = i;
955 
956 		rc = spdk_rdma_utils_get_translation(rqpair->mr_map, cmd, sizeof(*cmd), &translation);
957 		if (rc) {
958 			goto fail;
959 		}
960 		rdma_req->send_sgl[0].lkey = spdk_rdma_utils_memory_translation_get_lkey(&translation);
961 
962 		/* The first RDMA sgl element will always point
963 		 * at this data structure. Depending on whether
964 		 * an NVMe-oF SGL is required, the length of
965 		 * this element may change. */
966 		rdma_req->send_sgl[0].addr = (uint64_t)cmd;
967 		rdma_req->send_wr.wr_id = (uint64_t)&rdma_req->rdma_wr;
968 		rdma_req->send_wr.next = NULL;
969 		rdma_req->send_wr.opcode = IBV_WR_SEND;
970 		rdma_req->send_wr.send_flags = IBV_SEND_SIGNALED;
971 		rdma_req->send_wr.sg_list = rdma_req->send_sgl;
972 		rdma_req->send_wr.imm_data = 0;
973 
974 		TAILQ_INSERT_TAIL(&rqpair->free_reqs, rdma_req, link);
975 	}
976 
977 	return 0;
978 fail:
979 	nvme_rdma_free_reqs(rqpair);
980 	return -ENOMEM;
981 }
982 
983 static int nvme_rdma_connect(struct nvme_rdma_qpair *rqpair);
984 
985 static int
986 nvme_rdma_route_resolved(struct nvme_rdma_qpair *rqpair, int ret)
987 {
988 	if (ret) {
989 		SPDK_ERRLOG("RDMA route resolution error\n");
990 		return -1;
991 	}
992 
993 	ret = nvme_rdma_qpair_init(rqpair);
994 	if (ret < 0) {
995 		SPDK_ERRLOG("nvme_rdma_qpair_init() failed\n");
996 		return -1;
997 	}
998 
999 	return nvme_rdma_connect(rqpair);
1000 }
1001 
1002 static int
1003 nvme_rdma_addr_resolved(struct nvme_rdma_qpair *rqpair, int ret)
1004 {
1005 	if (ret) {
1006 		SPDK_ERRLOG("RDMA address resolution error\n");
1007 		return -1;
1008 	}
1009 
1010 	if (rqpair->qpair.ctrlr->opts.transport_ack_timeout != SPDK_NVME_TRANSPORT_ACK_TIMEOUT_DISABLED) {
1011 #ifdef SPDK_CONFIG_RDMA_SET_ACK_TIMEOUT
1012 		uint8_t timeout = rqpair->qpair.ctrlr->opts.transport_ack_timeout;
1013 		ret = rdma_set_option(rqpair->cm_id, RDMA_OPTION_ID,
1014 				      RDMA_OPTION_ID_ACK_TIMEOUT,
1015 				      &timeout, sizeof(timeout));
1016 		if (ret) {
1017 			SPDK_NOTICELOG("Can't apply RDMA_OPTION_ID_ACK_TIMEOUT %d, ret %d\n", timeout, ret);
1018 		}
1019 #else
1020 		SPDK_DEBUGLOG(nvme, "transport_ack_timeout is not supported\n");
1021 #endif
1022 	}
1023 
1024 	if (rqpair->qpair.ctrlr->opts.transport_tos != SPDK_NVME_TRANSPORT_TOS_DISABLED) {
1025 #ifdef SPDK_CONFIG_RDMA_SET_TOS
1026 		uint8_t tos = rqpair->qpair.ctrlr->opts.transport_tos;
1027 		ret = rdma_set_option(rqpair->cm_id, RDMA_OPTION_ID, RDMA_OPTION_ID_TOS, &tos, sizeof(tos));
1028 		if (ret) {
1029 			SPDK_NOTICELOG("Can't apply RDMA_OPTION_ID_TOS %u, ret %d\n", tos, ret);
1030 		}
1031 #else
1032 		SPDK_DEBUGLOG(nvme, "transport_tos is not supported\n");
1033 #endif
1034 	}
1035 
1036 	ret = rdma_resolve_route(rqpair->cm_id, NVME_RDMA_TIME_OUT_IN_MS);
1037 	if (ret) {
1038 		SPDK_ERRLOG("rdma_resolve_route\n");
1039 		return ret;
1040 	}
1041 
1042 	return nvme_rdma_process_event_start(rqpair, RDMA_CM_EVENT_ROUTE_RESOLVED,
1043 					     nvme_rdma_route_resolved);
1044 }
1045 
1046 static int
1047 nvme_rdma_resolve_addr(struct nvme_rdma_qpair *rqpair,
1048 		       struct sockaddr *src_addr,
1049 		       struct sockaddr *dst_addr)
1050 {
1051 	int ret;
1052 
1053 	if (src_addr) {
1054 		int reuse = 1;
1055 
1056 		ret = rdma_set_option(rqpair->cm_id, RDMA_OPTION_ID, RDMA_OPTION_ID_REUSEADDR,
1057 				      &reuse, sizeof(reuse));
1058 		if (ret) {
1059 			SPDK_NOTICELOG("Can't apply RDMA_OPTION_ID_REUSEADDR %d, ret %d\n",
1060 				       reuse, ret);
1061 			/* It is likely that rdma_resolve_addr() returns -EADDRINUSE, but
1062 			 * we may missing something. We rely on rdma_resolve_addr().
1063 			 */
1064 		}
1065 	}
1066 
1067 	ret = rdma_resolve_addr(rqpair->cm_id, src_addr, dst_addr,
1068 				NVME_RDMA_TIME_OUT_IN_MS);
1069 	if (ret) {
1070 		SPDK_ERRLOG("rdma_resolve_addr, %d\n", errno);
1071 		return ret;
1072 	}
1073 
1074 	return nvme_rdma_process_event_start(rqpair, RDMA_CM_EVENT_ADDR_RESOLVED,
1075 					     nvme_rdma_addr_resolved);
1076 }
1077 
1078 static int nvme_rdma_stale_conn_retry(struct nvme_rdma_qpair *rqpair);
1079 
1080 static int
1081 nvme_rdma_connect_established(struct nvme_rdma_qpair *rqpair, int ret)
1082 {
1083 	struct nvme_rdma_rsp_opts opts = {};
1084 
1085 	if (ret == -ESTALE) {
1086 		return nvme_rdma_stale_conn_retry(rqpair);
1087 	} else if (ret) {
1088 		SPDK_ERRLOG("RDMA connect error %d\n", ret);
1089 		return ret;
1090 	}
1091 
1092 	assert(!rqpair->mr_map);
1093 	rqpair->mr_map = spdk_rdma_utils_create_mem_map(rqpair->rdma_qp->qp->pd, &g_nvme_hooks,
1094 			 IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_READ | IBV_ACCESS_REMOTE_WRITE);
1095 	if (!rqpair->mr_map) {
1096 		SPDK_ERRLOG("Unable to register RDMA memory translation map\n");
1097 		return -1;
1098 	}
1099 
1100 	ret = nvme_rdma_create_reqs(rqpair);
1101 	SPDK_DEBUGLOG(nvme, "rc =%d\n", ret);
1102 	if (ret) {
1103 		SPDK_ERRLOG("Unable to create rqpair RDMA requests\n");
1104 		return -1;
1105 	}
1106 	SPDK_DEBUGLOG(nvme, "RDMA requests created\n");
1107 
1108 	if (!rqpair->srq) {
1109 		opts.num_entries = rqpair->num_entries;
1110 		opts.rqpair = rqpair;
1111 		opts.srq = NULL;
1112 		opts.mr_map = rqpair->mr_map;
1113 
1114 		assert(!rqpair->rsps);
1115 		rqpair->rsps = nvme_rdma_create_rsps(&opts);
1116 		if (!rqpair->rsps) {
1117 			SPDK_ERRLOG("Unable to create rqpair RDMA responses\n");
1118 			return -1;
1119 		}
1120 		SPDK_DEBUGLOG(nvme, "RDMA responses created\n");
1121 
1122 		ret = nvme_rdma_qpair_submit_recvs(rqpair);
1123 		SPDK_DEBUGLOG(nvme, "rc =%d\n", ret);
1124 		if (ret) {
1125 			SPDK_ERRLOG("Unable to submit rqpair RDMA responses\n");
1126 			return -1;
1127 		}
1128 		SPDK_DEBUGLOG(nvme, "RDMA responses submitted\n");
1129 	}
1130 
1131 	rqpair->state = NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_SEND;
1132 
1133 	return 0;
1134 }
1135 
1136 static int
1137 nvme_rdma_connect(struct nvme_rdma_qpair *rqpair)
1138 {
1139 	struct rdma_conn_param				param = {};
1140 	struct spdk_nvmf_rdma_request_private_data	request_data = {};
1141 	struct ibv_device_attr				attr;
1142 	int						ret;
1143 	struct spdk_nvme_ctrlr				*ctrlr;
1144 
1145 	ret = ibv_query_device(rqpair->cm_id->verbs, &attr);
1146 	if (ret != 0) {
1147 		SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
1148 		return ret;
1149 	}
1150 
1151 	param.responder_resources = attr.max_qp_rd_atom;
1152 
1153 	ctrlr = rqpair->qpair.ctrlr;
1154 	if (!ctrlr) {
1155 		return -1;
1156 	}
1157 
1158 	request_data.qid = rqpair->qpair.id;
1159 	request_data.hrqsize = rqpair->num_entries + 1;
1160 	request_data.hsqsize = rqpair->num_entries;
1161 	request_data.cntlid = ctrlr->cntlid;
1162 
1163 	param.private_data = &request_data;
1164 	param.private_data_len = sizeof(request_data);
1165 	param.retry_count = ctrlr->opts.transport_retry_count;
1166 	param.rnr_retry_count = 7;
1167 
1168 	/* Fields below are ignored by rdma cm if qpair has been
1169 	 * created using rdma cm API. */
1170 	param.srq = 0;
1171 	param.qp_num = rqpair->rdma_qp->qp->qp_num;
1172 
1173 	ret = rdma_connect(rqpair->cm_id, &param);
1174 	if (ret) {
1175 		SPDK_ERRLOG("nvme rdma connect error\n");
1176 		return ret;
1177 	}
1178 
1179 	ctrlr->numa.id_valid = 1;
1180 	ctrlr->numa.id = spdk_rdma_cm_id_get_numa_id(rqpair->cm_id);
1181 
1182 	return nvme_rdma_process_event_start(rqpair, RDMA_CM_EVENT_ESTABLISHED,
1183 					     nvme_rdma_connect_established);
1184 }
1185 
1186 static int
1187 nvme_rdma_ctrlr_connect_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
1188 {
1189 	struct sockaddr_storage dst_addr;
1190 	struct sockaddr_storage src_addr;
1191 	bool src_addr_specified;
1192 	long int port, src_port = 0;
1193 	int rc;
1194 	struct nvme_rdma_ctrlr *rctrlr;
1195 	struct nvme_rdma_qpair *rqpair;
1196 	struct nvme_rdma_poll_group *group;
1197 	int family;
1198 
1199 	rqpair = nvme_rdma_qpair(qpair);
1200 	rctrlr = nvme_rdma_ctrlr(ctrlr);
1201 	assert(rctrlr != NULL);
1202 
1203 	switch (ctrlr->trid.adrfam) {
1204 	case SPDK_NVMF_ADRFAM_IPV4:
1205 		family = AF_INET;
1206 		break;
1207 	case SPDK_NVMF_ADRFAM_IPV6:
1208 		family = AF_INET6;
1209 		break;
1210 	default:
1211 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", ctrlr->trid.adrfam);
1212 		return -1;
1213 	}
1214 
1215 	SPDK_DEBUGLOG(nvme, "adrfam %d ai_family %d\n", ctrlr->trid.adrfam, family);
1216 
1217 	memset(&dst_addr, 0, sizeof(dst_addr));
1218 
1219 	SPDK_DEBUGLOG(nvme, "trsvcid is %s\n", ctrlr->trid.trsvcid);
1220 	rc = nvme_parse_addr(&dst_addr, family, ctrlr->trid.traddr, ctrlr->trid.trsvcid, &port);
1221 	if (rc != 0) {
1222 		SPDK_ERRLOG("dst_addr nvme_parse_addr() failed\n");
1223 		return -1;
1224 	}
1225 
1226 	if (ctrlr->opts.src_addr[0] || ctrlr->opts.src_svcid[0]) {
1227 		memset(&src_addr, 0, sizeof(src_addr));
1228 		rc = nvme_parse_addr(&src_addr, family,
1229 				     ctrlr->opts.src_addr[0] ? ctrlr->opts.src_addr : NULL,
1230 				     ctrlr->opts.src_svcid[0] ? ctrlr->opts.src_svcid : NULL,
1231 				     &src_port);
1232 		if (rc != 0) {
1233 			SPDK_ERRLOG("src_addr nvme_parse_addr() failed\n");
1234 			return -1;
1235 		}
1236 		src_addr_specified = true;
1237 	} else {
1238 		src_addr_specified = false;
1239 	}
1240 
1241 	rc = rdma_create_id(rctrlr->cm_channel, &rqpair->cm_id, rqpair, RDMA_PS_TCP);
1242 	if (rc < 0) {
1243 		SPDK_ERRLOG("rdma_create_id() failed\n");
1244 		return -1;
1245 	}
1246 
1247 	rc = nvme_rdma_resolve_addr(rqpair,
1248 				    src_addr_specified ? (struct sockaddr *)&src_addr : NULL,
1249 				    (struct sockaddr *)&dst_addr);
1250 	if (rc < 0) {
1251 		SPDK_ERRLOG("nvme_rdma_resolve_addr() failed\n");
1252 		return -1;
1253 	}
1254 
1255 	rqpair->state = NVME_RDMA_QPAIR_STATE_INITIALIZING;
1256 
1257 	if (qpair->poll_group != NULL) {
1258 		group = nvme_rdma_poll_group(qpair->poll_group);
1259 		TAILQ_INSERT_TAIL(&group->connecting_qpairs, rqpair, link_connecting);
1260 	}
1261 
1262 	return 0;
1263 }
1264 
1265 static int
1266 nvme_rdma_stale_conn_reconnect(struct nvme_rdma_qpair *rqpair)
1267 {
1268 	struct spdk_nvme_qpair *qpair = &rqpair->qpair;
1269 
1270 	if (spdk_get_ticks() < rqpair->evt_timeout_ticks) {
1271 		return -EAGAIN;
1272 	}
1273 
1274 	return nvme_rdma_ctrlr_connect_qpair(qpair->ctrlr, qpair);
1275 }
1276 
1277 static int
1278 nvme_rdma_ctrlr_connect_qpair_poll(struct spdk_nvme_ctrlr *ctrlr,
1279 				   struct spdk_nvme_qpair *qpair)
1280 {
1281 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
1282 	int rc;
1283 
1284 	if (rqpair->in_connect_poll) {
1285 		return -EAGAIN;
1286 	}
1287 
1288 	rqpair->in_connect_poll = true;
1289 
1290 	switch (rqpair->state) {
1291 	case NVME_RDMA_QPAIR_STATE_INVALID:
1292 		rc = -EAGAIN;
1293 		break;
1294 
1295 	case NVME_RDMA_QPAIR_STATE_INITIALIZING:
1296 	case NVME_RDMA_QPAIR_STATE_EXITING:
1297 		if (!nvme_qpair_is_admin_queue(qpair)) {
1298 			nvme_ctrlr_lock(ctrlr);
1299 		}
1300 
1301 		rc = nvme_rdma_process_event_poll(rqpair);
1302 
1303 		if (!nvme_qpair_is_admin_queue(qpair)) {
1304 			nvme_ctrlr_unlock(ctrlr);
1305 		}
1306 
1307 		if (rc == 0) {
1308 			rc = -EAGAIN;
1309 		}
1310 		rqpair->in_connect_poll = false;
1311 
1312 		return rc;
1313 
1314 	case NVME_RDMA_QPAIR_STATE_STALE_CONN:
1315 		rc = nvme_rdma_stale_conn_reconnect(rqpair);
1316 		if (rc == 0) {
1317 			rc = -EAGAIN;
1318 		}
1319 		break;
1320 	case NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_SEND:
1321 		rc = nvme_fabric_qpair_connect_async(qpair, rqpair->num_entries + 1);
1322 		if (rc == 0) {
1323 			rqpair->state = NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_POLL;
1324 			rc = -EAGAIN;
1325 		} else {
1326 			SPDK_ERRLOG("Failed to send an NVMe-oF Fabric CONNECT command\n");
1327 		}
1328 		break;
1329 	case NVME_RDMA_QPAIR_STATE_FABRIC_CONNECT_POLL:
1330 		rc = nvme_fabric_qpair_connect_poll(qpair);
1331 		if (rc == 0) {
1332 			if (nvme_fabric_qpair_auth_required(qpair)) {
1333 				rc = nvme_fabric_qpair_authenticate_async(qpair);
1334 				if (rc == 0) {
1335 					rqpair->state = NVME_RDMA_QPAIR_STATE_AUTHENTICATING;
1336 					rc = -EAGAIN;
1337 				}
1338 			} else {
1339 				rqpair->state = NVME_RDMA_QPAIR_STATE_RUNNING;
1340 				nvme_qpair_set_state(qpair, NVME_QPAIR_CONNECTED);
1341 			}
1342 		} else if (rc != -EAGAIN) {
1343 			SPDK_ERRLOG("Failed to poll NVMe-oF Fabric CONNECT command\n");
1344 		}
1345 		break;
1346 	case NVME_RDMA_QPAIR_STATE_AUTHENTICATING:
1347 		rc = nvme_fabric_qpair_authenticate_poll(qpair);
1348 		if (rc == 0) {
1349 			rqpair->state = NVME_RDMA_QPAIR_STATE_RUNNING;
1350 			nvme_qpair_set_state(qpair, NVME_QPAIR_CONNECTED);
1351 		}
1352 		break;
1353 	case NVME_RDMA_QPAIR_STATE_RUNNING:
1354 		rc = 0;
1355 		break;
1356 	default:
1357 		assert(false);
1358 		rc = -EINVAL;
1359 		break;
1360 	}
1361 
1362 	rqpair->in_connect_poll = false;
1363 
1364 	return rc;
1365 }
1366 
1367 static inline int
1368 nvme_rdma_get_memory_translation(struct nvme_request *req, struct nvme_rdma_qpair *rqpair,
1369 				 struct nvme_rdma_memory_translation_ctx *_ctx)
1370 {
1371 	struct spdk_memory_domain_translation_ctx ctx;
1372 	struct spdk_memory_domain_translation_result dma_translation = {.iov_count = 0};
1373 	struct spdk_rdma_utils_memory_translation rdma_translation;
1374 	int rc;
1375 
1376 	assert(req);
1377 	assert(rqpair);
1378 	assert(_ctx);
1379 
1380 	if (req->payload.opts && req->payload.opts->memory_domain) {
1381 		ctx.size = sizeof(struct spdk_memory_domain_translation_ctx);
1382 		ctx.rdma.ibv_qp = rqpair->rdma_qp->qp;
1383 		dma_translation.size = sizeof(struct spdk_memory_domain_translation_result);
1384 
1385 		rc = spdk_memory_domain_translate_data(req->payload.opts->memory_domain,
1386 						       req->payload.opts->memory_domain_ctx,
1387 						       rqpair->memory_domain, &ctx, _ctx->addr,
1388 						       _ctx->length, &dma_translation);
1389 		if (spdk_unlikely(rc) || dma_translation.iov_count != 1) {
1390 			SPDK_ERRLOG("DMA memory translation failed, rc %d, iov count %u\n", rc, dma_translation.iov_count);
1391 			return rc;
1392 		}
1393 
1394 		_ctx->lkey = dma_translation.rdma.lkey;
1395 		_ctx->rkey = dma_translation.rdma.rkey;
1396 		_ctx->addr = dma_translation.iov.iov_base;
1397 		_ctx->length = dma_translation.iov.iov_len;
1398 	} else {
1399 		rc = spdk_rdma_utils_get_translation(rqpair->mr_map, _ctx->addr, _ctx->length, &rdma_translation);
1400 		if (spdk_unlikely(rc)) {
1401 			SPDK_ERRLOG("RDMA memory translation failed, rc %d\n", rc);
1402 			return rc;
1403 		}
1404 		if (rdma_translation.translation_type == SPDK_RDMA_UTILS_TRANSLATION_MR) {
1405 			_ctx->lkey = rdma_translation.mr_or_key.mr->lkey;
1406 			_ctx->rkey = rdma_translation.mr_or_key.mr->rkey;
1407 		} else {
1408 			_ctx->lkey = _ctx->rkey = (uint32_t)rdma_translation.mr_or_key.key;
1409 		}
1410 	}
1411 
1412 	return 0;
1413 }
1414 
1415 
1416 /*
1417  * Build SGL describing empty payload.
1418  */
1419 static int
1420 nvme_rdma_build_null_request(struct spdk_nvme_rdma_req *rdma_req)
1421 {
1422 	struct nvme_request *req = rdma_req->req;
1423 
1424 	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
1425 
1426 	/* The first element of this SGL is pointing at an
1427 	 * spdk_nvmf_cmd object. For this particular command,
1428 	 * we only need the first 64 bytes corresponding to
1429 	 * the NVMe command. */
1430 	rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd);
1431 
1432 	/* The RDMA SGL needs one element describing the NVMe command. */
1433 	rdma_req->send_wr.num_sge = 1;
1434 
1435 	req->cmd.dptr.sgl1.keyed.type = SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK;
1436 	req->cmd.dptr.sgl1.keyed.subtype = SPDK_NVME_SGL_SUBTYPE_ADDRESS;
1437 	req->cmd.dptr.sgl1.keyed.length = 0;
1438 	req->cmd.dptr.sgl1.keyed.key = 0;
1439 	req->cmd.dptr.sgl1.address = 0;
1440 
1441 	return 0;
1442 }
1443 
1444 /*
1445  * Build inline SGL describing contiguous payload buffer.
1446  */
1447 static int
1448 nvme_rdma_build_contig_inline_request(struct nvme_rdma_qpair *rqpair,
1449 				      struct spdk_nvme_rdma_req *rdma_req)
1450 {
1451 	struct nvme_request *req = rdma_req->req;
1452 	struct nvme_rdma_memory_translation_ctx ctx = {
1453 		.addr = (uint8_t *)req->payload.contig_or_cb_arg + req->payload_offset,
1454 		.length = req->payload_size
1455 	};
1456 	int rc;
1457 
1458 	assert(ctx.length != 0);
1459 	assert(nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_CONTIG);
1460 
1461 	rc = nvme_rdma_get_memory_translation(req, rqpair, &ctx);
1462 	if (spdk_unlikely(rc)) {
1463 		return -1;
1464 	}
1465 
1466 	rdma_req->send_sgl[1].lkey = ctx.lkey;
1467 
1468 	/* The first element of this SGL is pointing at an
1469 	 * spdk_nvmf_cmd object. For this particular command,
1470 	 * we only need the first 64 bytes corresponding to
1471 	 * the NVMe command. */
1472 	rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd);
1473 
1474 	rdma_req->send_sgl[1].addr = (uint64_t)ctx.addr;
1475 	rdma_req->send_sgl[1].length = (uint32_t)ctx.length;
1476 
1477 	/* The RDMA SGL contains two elements. The first describes
1478 	 * the NVMe command and the second describes the data
1479 	 * payload. */
1480 	rdma_req->send_wr.num_sge = 2;
1481 
1482 	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
1483 	req->cmd.dptr.sgl1.unkeyed.type = SPDK_NVME_SGL_TYPE_DATA_BLOCK;
1484 	req->cmd.dptr.sgl1.unkeyed.subtype = SPDK_NVME_SGL_SUBTYPE_OFFSET;
1485 	req->cmd.dptr.sgl1.unkeyed.length = (uint32_t)ctx.length;
1486 	/* Inline only supported for icdoff == 0 currently.  This function will
1487 	 * not get called for controllers with other values. */
1488 	req->cmd.dptr.sgl1.address = (uint64_t)0;
1489 
1490 	return 0;
1491 }
1492 
1493 /*
1494  * Build SGL describing contiguous payload buffer.
1495  */
1496 static int
1497 nvme_rdma_build_contig_request(struct nvme_rdma_qpair *rqpair,
1498 			       struct spdk_nvme_rdma_req *rdma_req)
1499 {
1500 	struct nvme_request *req = rdma_req->req;
1501 	struct nvme_rdma_memory_translation_ctx ctx = {
1502 		.addr = (uint8_t *)req->payload.contig_or_cb_arg + req->payload_offset,
1503 		.length = req->payload_size
1504 	};
1505 	int rc;
1506 
1507 	assert(req->payload_size != 0);
1508 	assert(nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_CONTIG);
1509 
1510 	if (spdk_unlikely(req->payload_size > NVME_RDMA_MAX_KEYED_SGL_LENGTH)) {
1511 		SPDK_ERRLOG("SGL length %u exceeds max keyed SGL block size %u\n",
1512 			    req->payload_size, NVME_RDMA_MAX_KEYED_SGL_LENGTH);
1513 		return -1;
1514 	}
1515 
1516 	rc = nvme_rdma_get_memory_translation(req, rqpair, &ctx);
1517 	if (spdk_unlikely(rc)) {
1518 		return -1;
1519 	}
1520 
1521 	req->cmd.dptr.sgl1.keyed.key = ctx.rkey;
1522 
1523 	/* The first element of this SGL is pointing at an
1524 	 * spdk_nvmf_cmd object. For this particular command,
1525 	 * we only need the first 64 bytes corresponding to
1526 	 * the NVMe command. */
1527 	rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd);
1528 
1529 	/* The RDMA SGL needs one element describing the NVMe command. */
1530 	rdma_req->send_wr.num_sge = 1;
1531 
1532 	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
1533 	req->cmd.dptr.sgl1.keyed.type = SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK;
1534 	req->cmd.dptr.sgl1.keyed.subtype = SPDK_NVME_SGL_SUBTYPE_ADDRESS;
1535 	req->cmd.dptr.sgl1.keyed.length = (uint32_t)ctx.length;
1536 	req->cmd.dptr.sgl1.address = (uint64_t)ctx.addr;
1537 
1538 	return 0;
1539 }
1540 
1541 /*
1542  * Build SGL describing scattered payload buffer.
1543  */
1544 static int
1545 nvme_rdma_build_sgl_request(struct nvme_rdma_qpair *rqpair,
1546 			    struct spdk_nvme_rdma_req *rdma_req)
1547 {
1548 	struct nvme_request *req = rdma_req->req;
1549 	struct spdk_nvmf_cmd *cmd = &rqpair->cmds[rdma_req->id];
1550 	struct nvme_rdma_memory_translation_ctx ctx;
1551 	uint32_t remaining_size;
1552 	uint32_t sge_length;
1553 	int rc, max_num_sgl, num_sgl_desc;
1554 
1555 	assert(req->payload_size != 0);
1556 	assert(nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_SGL);
1557 	assert(req->payload.reset_sgl_fn != NULL);
1558 	assert(req->payload.next_sge_fn != NULL);
1559 	req->payload.reset_sgl_fn(req->payload.contig_or_cb_arg, req->payload_offset);
1560 
1561 	max_num_sgl = req->qpair->ctrlr->max_sges;
1562 
1563 	remaining_size = req->payload_size;
1564 	num_sgl_desc = 0;
1565 	do {
1566 		rc = req->payload.next_sge_fn(req->payload.contig_or_cb_arg, &ctx.addr, &sge_length);
1567 		if (rc) {
1568 			return -1;
1569 		}
1570 
1571 		sge_length = spdk_min(remaining_size, sge_length);
1572 
1573 		if (spdk_unlikely(sge_length > NVME_RDMA_MAX_KEYED_SGL_LENGTH)) {
1574 			SPDK_ERRLOG("SGL length %u exceeds max keyed SGL block size %u\n",
1575 				    sge_length, NVME_RDMA_MAX_KEYED_SGL_LENGTH);
1576 			return -1;
1577 		}
1578 		ctx.length = sge_length;
1579 		rc = nvme_rdma_get_memory_translation(req, rqpair, &ctx);
1580 		if (spdk_unlikely(rc)) {
1581 			return -1;
1582 		}
1583 
1584 		cmd->sgl[num_sgl_desc].keyed.key = ctx.rkey;
1585 		cmd->sgl[num_sgl_desc].keyed.type = SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK;
1586 		cmd->sgl[num_sgl_desc].keyed.subtype = SPDK_NVME_SGL_SUBTYPE_ADDRESS;
1587 		cmd->sgl[num_sgl_desc].keyed.length = (uint32_t)ctx.length;
1588 		cmd->sgl[num_sgl_desc].address = (uint64_t)ctx.addr;
1589 
1590 		remaining_size -= ctx.length;
1591 		num_sgl_desc++;
1592 	} while (remaining_size > 0 && num_sgl_desc < max_num_sgl);
1593 
1594 
1595 	/* Should be impossible if we did our sgl checks properly up the stack, but do a sanity check here. */
1596 	if (remaining_size > 0) {
1597 		return -1;
1598 	}
1599 
1600 	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
1601 
1602 	/* The RDMA SGL needs one element describing some portion
1603 	 * of the spdk_nvmf_cmd structure. */
1604 	rdma_req->send_wr.num_sge = 1;
1605 
1606 	/*
1607 	 * If only one SGL descriptor is required, it can be embedded directly in the command
1608 	 * as a data block descriptor.
1609 	 */
1610 	if (num_sgl_desc == 1) {
1611 		/* The first element of this SGL is pointing at an
1612 		 * spdk_nvmf_cmd object. For this particular command,
1613 		 * we only need the first 64 bytes corresponding to
1614 		 * the NVMe command. */
1615 		rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd);
1616 
1617 		req->cmd.dptr.sgl1.keyed.type = cmd->sgl[0].keyed.type;
1618 		req->cmd.dptr.sgl1.keyed.subtype = cmd->sgl[0].keyed.subtype;
1619 		req->cmd.dptr.sgl1.keyed.length = cmd->sgl[0].keyed.length;
1620 		req->cmd.dptr.sgl1.keyed.key = cmd->sgl[0].keyed.key;
1621 		req->cmd.dptr.sgl1.address = cmd->sgl[0].address;
1622 	} else {
1623 		/*
1624 		 * Otherwise, The SGL descriptor embedded in the command must point to the list of
1625 		 * SGL descriptors used to describe the operation. In that case it is a last segment descriptor.
1626 		 */
1627 		uint32_t descriptors_size = sizeof(struct spdk_nvme_sgl_descriptor) * num_sgl_desc;
1628 
1629 		if (spdk_unlikely(descriptors_size > rqpair->qpair.ctrlr->ioccsz_bytes)) {
1630 			SPDK_ERRLOG("Size of SGL descriptors (%u) exceeds ICD (%u)\n",
1631 				    descriptors_size, rqpair->qpair.ctrlr->ioccsz_bytes);
1632 			return -1;
1633 		}
1634 		rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd) + descriptors_size;
1635 
1636 		req->cmd.dptr.sgl1.unkeyed.type = SPDK_NVME_SGL_TYPE_LAST_SEGMENT;
1637 		req->cmd.dptr.sgl1.unkeyed.subtype = SPDK_NVME_SGL_SUBTYPE_OFFSET;
1638 		req->cmd.dptr.sgl1.unkeyed.length = descriptors_size;
1639 		req->cmd.dptr.sgl1.address = (uint64_t)0;
1640 	}
1641 
1642 	return 0;
1643 }
1644 
1645 /*
1646  * Build inline SGL describing sgl payload buffer.
1647  */
1648 static int
1649 nvme_rdma_build_sgl_inline_request(struct nvme_rdma_qpair *rqpair,
1650 				   struct spdk_nvme_rdma_req *rdma_req)
1651 {
1652 	struct nvme_request *req = rdma_req->req;
1653 	struct nvme_rdma_memory_translation_ctx ctx;
1654 	uint32_t length;
1655 	int rc;
1656 
1657 	assert(req->payload_size != 0);
1658 	assert(nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_SGL);
1659 	assert(req->payload.reset_sgl_fn != NULL);
1660 	assert(req->payload.next_sge_fn != NULL);
1661 	req->payload.reset_sgl_fn(req->payload.contig_or_cb_arg, req->payload_offset);
1662 
1663 	rc = req->payload.next_sge_fn(req->payload.contig_or_cb_arg, &ctx.addr, &length);
1664 	if (rc) {
1665 		return -1;
1666 	}
1667 
1668 	if (length < req->payload_size) {
1669 		SPDK_DEBUGLOG(nvme, "Inline SGL request split so sending separately.\n");
1670 		return nvme_rdma_build_sgl_request(rqpair, rdma_req);
1671 	}
1672 
1673 	if (length > req->payload_size) {
1674 		length = req->payload_size;
1675 	}
1676 
1677 	ctx.length = length;
1678 	rc = nvme_rdma_get_memory_translation(req, rqpair, &ctx);
1679 	if (spdk_unlikely(rc)) {
1680 		return -1;
1681 	}
1682 
1683 	rdma_req->send_sgl[1].addr = (uint64_t)ctx.addr;
1684 	rdma_req->send_sgl[1].length = (uint32_t)ctx.length;
1685 	rdma_req->send_sgl[1].lkey = ctx.lkey;
1686 
1687 	rdma_req->send_wr.num_sge = 2;
1688 
1689 	/* The first element of this SGL is pointing at an
1690 	 * spdk_nvmf_cmd object. For this particular command,
1691 	 * we only need the first 64 bytes corresponding to
1692 	 * the NVMe command. */
1693 	rdma_req->send_sgl[0].length = sizeof(struct spdk_nvme_cmd);
1694 
1695 	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
1696 	req->cmd.dptr.sgl1.unkeyed.type = SPDK_NVME_SGL_TYPE_DATA_BLOCK;
1697 	req->cmd.dptr.sgl1.unkeyed.subtype = SPDK_NVME_SGL_SUBTYPE_OFFSET;
1698 	req->cmd.dptr.sgl1.unkeyed.length = (uint32_t)ctx.length;
1699 	/* Inline only supported for icdoff == 0 currently.  This function will
1700 	 * not get called for controllers with other values. */
1701 	req->cmd.dptr.sgl1.address = (uint64_t)0;
1702 
1703 	return 0;
1704 }
1705 
1706 static int
1707 nvme_rdma_req_init(struct nvme_rdma_qpair *rqpair, struct nvme_request *req,
1708 		   struct spdk_nvme_rdma_req *rdma_req)
1709 {
1710 	struct spdk_nvme_ctrlr *ctrlr = rqpair->qpair.ctrlr;
1711 	enum nvme_payload_type payload_type;
1712 	bool icd_supported;
1713 	int rc;
1714 
1715 	assert(rdma_req->req == NULL);
1716 	rdma_req->req = req;
1717 	req->cmd.cid = rdma_req->id;
1718 	payload_type = nvme_payload_type(&req->payload);
1719 	/*
1720 	 * Check if icdoff is non zero, to avoid interop conflicts with
1721 	 * targets with non-zero icdoff.  Both SPDK and the Linux kernel
1722 	 * targets use icdoff = 0.  For targets with non-zero icdoff, we
1723 	 * will currently just not use inline data for now.
1724 	 */
1725 	icd_supported = spdk_nvme_opc_get_data_transfer(req->cmd.opc) == SPDK_NVME_DATA_HOST_TO_CONTROLLER
1726 			&& req->payload_size <= ctrlr->ioccsz_bytes && ctrlr->icdoff == 0;
1727 
1728 	if (req->payload_size == 0) {
1729 		rc = nvme_rdma_build_null_request(rdma_req);
1730 	} else if (payload_type == NVME_PAYLOAD_TYPE_CONTIG) {
1731 		if (icd_supported) {
1732 			rc = nvme_rdma_build_contig_inline_request(rqpair, rdma_req);
1733 		} else {
1734 			rc = nvme_rdma_build_contig_request(rqpair, rdma_req);
1735 		}
1736 	} else if (payload_type == NVME_PAYLOAD_TYPE_SGL) {
1737 		if (icd_supported) {
1738 			rc = nvme_rdma_build_sgl_inline_request(rqpair, rdma_req);
1739 		} else {
1740 			rc = nvme_rdma_build_sgl_request(rqpair, rdma_req);
1741 		}
1742 	} else {
1743 		rc = -1;
1744 	}
1745 
1746 	if (rc) {
1747 		rdma_req->req = NULL;
1748 		return rc;
1749 	}
1750 
1751 	memcpy(&rqpair->cmds[rdma_req->id], &req->cmd, sizeof(req->cmd));
1752 	return 0;
1753 }
1754 
1755 static struct spdk_nvme_qpair *
1756 nvme_rdma_ctrlr_create_qpair(struct spdk_nvme_ctrlr *ctrlr,
1757 			     uint16_t qid, uint32_t qsize,
1758 			     enum spdk_nvme_qprio qprio,
1759 			     uint32_t num_requests,
1760 			     bool delay_cmd_submit,
1761 			     bool async)
1762 {
1763 	struct nvme_rdma_qpair *rqpair;
1764 	struct spdk_nvme_qpair *qpair;
1765 	int rc;
1766 
1767 	if (qsize < SPDK_NVME_QUEUE_MIN_ENTRIES) {
1768 		SPDK_ERRLOG("Failed to create qpair with size %u. Minimum queue size is %d.\n",
1769 			    qsize, SPDK_NVME_QUEUE_MIN_ENTRIES);
1770 		return NULL;
1771 	}
1772 
1773 	rqpair = spdk_zmalloc(sizeof(struct nvme_rdma_qpair), 0, NULL, SPDK_ENV_NUMA_ID_ANY,
1774 			      SPDK_MALLOC_DMA);
1775 	if (!rqpair) {
1776 		SPDK_ERRLOG("failed to get create rqpair\n");
1777 		return NULL;
1778 	}
1779 
1780 	/* Set num_entries one less than queue size. According to NVMe
1781 	 * and NVMe-oF specs we can not submit queue size requests,
1782 	 * one slot shall always remain empty.
1783 	 */
1784 	rqpair->num_entries = qsize - 1;
1785 	rqpair->delay_cmd_submit = delay_cmd_submit;
1786 	rqpair->state = NVME_RDMA_QPAIR_STATE_INVALID;
1787 	qpair = &rqpair->qpair;
1788 	rc = nvme_qpair_init(qpair, qid, ctrlr, qprio, num_requests, async);
1789 	if (rc != 0) {
1790 		spdk_free(rqpair);
1791 		return NULL;
1792 	}
1793 
1794 	return qpair;
1795 }
1796 
1797 static void
1798 nvme_rdma_qpair_destroy(struct nvme_rdma_qpair *rqpair)
1799 {
1800 	struct spdk_nvme_qpair *qpair = &rqpair->qpair;
1801 	struct nvme_rdma_ctrlr *rctrlr;
1802 	struct nvme_rdma_cm_event_entry *entry, *tmp;
1803 
1804 	spdk_rdma_utils_free_mem_map(&rqpair->mr_map);
1805 
1806 	if (rqpair->evt) {
1807 		rdma_ack_cm_event(rqpair->evt);
1808 		rqpair->evt = NULL;
1809 	}
1810 
1811 	/*
1812 	 * This works because we have the controller lock both in
1813 	 * this function and in the function where we add new events.
1814 	 */
1815 	if (qpair->ctrlr != NULL) {
1816 		rctrlr = nvme_rdma_ctrlr(qpair->ctrlr);
1817 		STAILQ_FOREACH_SAFE(entry, &rctrlr->pending_cm_events, link, tmp) {
1818 			if (entry->evt->id->context == rqpair) {
1819 				STAILQ_REMOVE(&rctrlr->pending_cm_events, entry, nvme_rdma_cm_event_entry, link);
1820 				rdma_ack_cm_event(entry->evt);
1821 				STAILQ_INSERT_HEAD(&rctrlr->free_cm_events, entry, link);
1822 			}
1823 		}
1824 	}
1825 
1826 	if (rqpair->cm_id) {
1827 		if (rqpair->rdma_qp) {
1828 			spdk_rdma_utils_put_pd(rqpair->rdma_qp->qp->pd);
1829 			spdk_rdma_provider_qp_destroy(rqpair->rdma_qp);
1830 			rqpair->rdma_qp = NULL;
1831 		}
1832 	}
1833 
1834 	if (rqpair->poller) {
1835 		struct nvme_rdma_poll_group     *group;
1836 
1837 		assert(qpair->poll_group);
1838 		group = nvme_rdma_poll_group(qpair->poll_group);
1839 
1840 		nvme_rdma_poll_group_put_poller(group, rqpair->poller);
1841 
1842 		rqpair->poller = NULL;
1843 		rqpair->cq = NULL;
1844 		if (rqpair->srq) {
1845 			rqpair->srq = NULL;
1846 			rqpair->rsps = NULL;
1847 		}
1848 	} else if (rqpair->cq) {
1849 		ibv_destroy_cq(rqpair->cq);
1850 		rqpair->cq = NULL;
1851 	}
1852 
1853 	nvme_rdma_free_reqs(rqpair);
1854 	nvme_rdma_free_rsps(rqpair->rsps);
1855 	rqpair->rsps = NULL;
1856 
1857 	/* destroy cm_id last so cma device will not be freed before we destroy the cq. */
1858 	if (rqpair->cm_id) {
1859 		rdma_destroy_id(rqpair->cm_id);
1860 		rqpair->cm_id = NULL;
1861 	}
1862 }
1863 
1864 static void nvme_rdma_qpair_abort_reqs(struct spdk_nvme_qpair *qpair, uint32_t dnr);
1865 
1866 static int
1867 nvme_rdma_qpair_disconnected(struct nvme_rdma_qpair *rqpair, int ret)
1868 {
1869 	if (ret) {
1870 		SPDK_DEBUGLOG(nvme, "Target did not respond to qpair disconnect.\n");
1871 		goto quiet;
1872 	}
1873 
1874 	if (rqpair->poller == NULL) {
1875 		/* If poller is not used, cq is not shared.
1876 		 * So complete disconnecting qpair immediately.
1877 		 */
1878 		goto quiet;
1879 	}
1880 
1881 	if (rqpair->rsps == NULL) {
1882 		goto quiet;
1883 	}
1884 
1885 	if (rqpair->need_destroy ||
1886 	    (rqpair->current_num_sends != 0 ||
1887 	     (!rqpair->srq && rqpair->rsps->current_num_recvs != 0))) {
1888 		rqpair->state = NVME_RDMA_QPAIR_STATE_LINGERING;
1889 		rqpair->evt_timeout_ticks = (NVME_RDMA_DISCONNECTED_QPAIR_TIMEOUT_US * spdk_get_ticks_hz()) /
1890 					    SPDK_SEC_TO_USEC + spdk_get_ticks();
1891 
1892 		return -EAGAIN;
1893 	}
1894 
1895 quiet:
1896 	rqpair->state = NVME_RDMA_QPAIR_STATE_EXITED;
1897 
1898 	nvme_rdma_qpair_abort_reqs(&rqpair->qpair, rqpair->qpair.abort_dnr);
1899 	nvme_rdma_qpair_destroy(rqpair);
1900 	nvme_transport_ctrlr_disconnect_qpair_done(&rqpair->qpair);
1901 
1902 	return 0;
1903 }
1904 
1905 static int
1906 nvme_rdma_qpair_wait_until_quiet(struct nvme_rdma_qpair *rqpair)
1907 {
1908 	struct spdk_nvme_qpair *qpair = &rqpair->qpair;
1909 	struct spdk_nvme_ctrlr *ctrlr = qpair->ctrlr;
1910 
1911 	if (spdk_get_ticks() < rqpair->evt_timeout_ticks &&
1912 	    (rqpair->current_num_sends != 0 ||
1913 	     (!rqpair->srq && rqpair->rsps->current_num_recvs != 0))) {
1914 		return -EAGAIN;
1915 	}
1916 
1917 	rqpair->state = NVME_RDMA_QPAIR_STATE_EXITED;
1918 	nvme_rdma_qpair_abort_reqs(qpair, qpair->abort_dnr);
1919 	if (!nvme_qpair_is_admin_queue(qpair)) {
1920 		nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
1921 	}
1922 	nvme_rdma_qpair_destroy(rqpair);
1923 	if (!nvme_qpair_is_admin_queue(qpair)) {
1924 		nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
1925 	}
1926 	nvme_transport_ctrlr_disconnect_qpair_done(&rqpair->qpair);
1927 
1928 	return 0;
1929 }
1930 
1931 static void
1932 _nvme_rdma_ctrlr_disconnect_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair,
1933 				  nvme_rdma_cm_event_cb disconnected_qpair_cb)
1934 {
1935 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
1936 	int rc;
1937 
1938 	assert(disconnected_qpair_cb != NULL);
1939 
1940 	rqpair->state = NVME_RDMA_QPAIR_STATE_EXITING;
1941 
1942 	if (rqpair->cm_id) {
1943 		if (rqpair->rdma_qp) {
1944 			rc = spdk_rdma_provider_qp_disconnect(rqpair->rdma_qp);
1945 			if ((qpair->ctrlr != NULL) && (rc == 0)) {
1946 				rc = nvme_rdma_process_event_start(rqpair, RDMA_CM_EVENT_DISCONNECTED,
1947 								   disconnected_qpair_cb);
1948 				if (rc == 0) {
1949 					return;
1950 				}
1951 			}
1952 		}
1953 	}
1954 
1955 	disconnected_qpair_cb(rqpair, 0);
1956 }
1957 
1958 static int
1959 nvme_rdma_ctrlr_disconnect_qpair_poll(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
1960 {
1961 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
1962 	int rc;
1963 
1964 	switch (rqpair->state) {
1965 	case NVME_RDMA_QPAIR_STATE_EXITING:
1966 		if (!nvme_qpair_is_admin_queue(qpair)) {
1967 			nvme_ctrlr_lock(ctrlr);
1968 		}
1969 
1970 		rc = nvme_rdma_process_event_poll(rqpair);
1971 
1972 		if (!nvme_qpair_is_admin_queue(qpair)) {
1973 			nvme_ctrlr_unlock(ctrlr);
1974 		}
1975 		break;
1976 
1977 	case NVME_RDMA_QPAIR_STATE_LINGERING:
1978 		rc = nvme_rdma_qpair_wait_until_quiet(rqpair);
1979 		break;
1980 	case NVME_RDMA_QPAIR_STATE_EXITED:
1981 		rc = 0;
1982 		break;
1983 
1984 	default:
1985 		assert(false);
1986 		rc = -EAGAIN;
1987 		break;
1988 	}
1989 
1990 	return rc;
1991 }
1992 
1993 static void
1994 nvme_rdma_ctrlr_disconnect_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
1995 {
1996 	int rc;
1997 
1998 	_nvme_rdma_ctrlr_disconnect_qpair(ctrlr, qpair, nvme_rdma_qpair_disconnected);
1999 
2000 	/* If the async mode is disabled, poll the qpair until it is actually disconnected.
2001 	 * It is ensured that poll_group_process_completions() calls disconnected_qpair_cb
2002 	 * for any disconnected qpair. Hence, we do not have to check if the qpair is in
2003 	 * a poll group or not.
2004 	 * At the same time, if the qpair is being destroyed, i.e. this function is called by
2005 	 * spdk_nvme_ctrlr_free_io_qpair then we need to wait until qpair is disconnected, otherwise
2006 	 * we may leak some resources.
2007 	 */
2008 	if (qpair->async && !qpair->destroy_in_progress) {
2009 		return;
2010 	}
2011 
2012 	while (1) {
2013 		rc = nvme_rdma_ctrlr_disconnect_qpair_poll(ctrlr, qpair);
2014 		if (rc != -EAGAIN) {
2015 			break;
2016 		}
2017 	}
2018 }
2019 
2020 static int
2021 nvme_rdma_stale_conn_disconnected(struct nvme_rdma_qpair *rqpair, int ret)
2022 {
2023 	struct spdk_nvme_qpair *qpair = &rqpair->qpair;
2024 
2025 	if (ret) {
2026 		SPDK_DEBUGLOG(nvme, "Target did not respond to qpair disconnect.\n");
2027 	}
2028 
2029 	nvme_rdma_qpair_destroy(rqpair);
2030 
2031 	qpair->last_transport_failure_reason = qpair->transport_failure_reason;
2032 	qpair->transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_NONE;
2033 
2034 	rqpair->state = NVME_RDMA_QPAIR_STATE_STALE_CONN;
2035 	rqpair->evt_timeout_ticks = (NVME_RDMA_STALE_CONN_RETRY_DELAY_US * spdk_get_ticks_hz()) /
2036 				    SPDK_SEC_TO_USEC + spdk_get_ticks();
2037 
2038 	return 0;
2039 }
2040 
2041 static int
2042 nvme_rdma_stale_conn_retry(struct nvme_rdma_qpair *rqpair)
2043 {
2044 	struct spdk_nvme_qpair *qpair = &rqpair->qpair;
2045 
2046 	if (rqpair->stale_conn_retry_count >= NVME_RDMA_STALE_CONN_RETRY_MAX) {
2047 		SPDK_ERRLOG("Retry failed %d times, give up stale connection to qpair (cntlid:%u, qid:%u).\n",
2048 			    NVME_RDMA_STALE_CONN_RETRY_MAX, qpair->ctrlr->cntlid, qpair->id);
2049 		return -ESTALE;
2050 	}
2051 
2052 	rqpair->stale_conn_retry_count++;
2053 
2054 	SPDK_NOTICELOG("%d times, retry stale connection to qpair (cntlid:%u, qid:%u).\n",
2055 		       rqpair->stale_conn_retry_count, qpair->ctrlr->cntlid, qpair->id);
2056 
2057 	_nvme_rdma_ctrlr_disconnect_qpair(qpair->ctrlr, qpair, nvme_rdma_stale_conn_disconnected);
2058 
2059 	return 0;
2060 }
2061 
2062 static int
2063 nvme_rdma_ctrlr_delete_io_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
2064 {
2065 	struct nvme_rdma_qpair *rqpair;
2066 
2067 	assert(qpair != NULL);
2068 	rqpair = nvme_rdma_qpair(qpair);
2069 
2070 	if (rqpair->state != NVME_RDMA_QPAIR_STATE_EXITED) {
2071 		int rc __attribute__((unused));
2072 
2073 		/* qpair was removed from the poll group while the disconnect is not finished.
2074 		 * Destroy rdma resources forcefully. */
2075 		rc = nvme_rdma_qpair_disconnected(rqpair, 0);
2076 		assert(rc == 0);
2077 	}
2078 
2079 	nvme_rdma_qpair_abort_reqs(qpair, qpair->abort_dnr);
2080 	nvme_qpair_deinit(qpair);
2081 
2082 	if (spdk_rdma_utils_put_memory_domain(rqpair->memory_domain) != 0) {
2083 		SPDK_ERRLOG("Failed to release memory domain\n");
2084 		assert(0);
2085 	}
2086 
2087 	spdk_free(rqpair);
2088 
2089 	return 0;
2090 }
2091 
2092 static struct spdk_nvme_qpair *
2093 nvme_rdma_ctrlr_create_io_qpair(struct spdk_nvme_ctrlr *ctrlr, uint16_t qid,
2094 				const struct spdk_nvme_io_qpair_opts *opts)
2095 {
2096 	return nvme_rdma_ctrlr_create_qpair(ctrlr, qid, opts->io_queue_size, opts->qprio,
2097 					    opts->io_queue_requests,
2098 					    opts->delay_cmd_submit,
2099 					    opts->async_mode);
2100 }
2101 
2102 static int
2103 nvme_rdma_ctrlr_enable(struct spdk_nvme_ctrlr *ctrlr)
2104 {
2105 	/* do nothing here */
2106 	return 0;
2107 }
2108 
2109 static int nvme_rdma_ctrlr_destruct(struct spdk_nvme_ctrlr *ctrlr);
2110 
2111 /* We have to use the typedef in the function declaration to appease astyle. */
2112 typedef struct spdk_nvme_ctrlr spdk_nvme_ctrlr_t;
2113 
2114 static spdk_nvme_ctrlr_t *
2115 nvme_rdma_ctrlr_construct(const struct spdk_nvme_transport_id *trid,
2116 			  const struct spdk_nvme_ctrlr_opts *opts,
2117 			  void *devhandle)
2118 {
2119 	struct nvme_rdma_ctrlr *rctrlr;
2120 	struct ibv_context **contexts;
2121 	struct ibv_device_attr dev_attr;
2122 	int i, flag, rc;
2123 
2124 	rctrlr = spdk_zmalloc(sizeof(struct nvme_rdma_ctrlr), 0, NULL, SPDK_ENV_NUMA_ID_ANY,
2125 			      SPDK_MALLOC_DMA);
2126 	if (rctrlr == NULL) {
2127 		SPDK_ERRLOG("could not allocate ctrlr\n");
2128 		return NULL;
2129 	}
2130 
2131 	rctrlr->ctrlr.opts = *opts;
2132 	rctrlr->ctrlr.trid = *trid;
2133 
2134 	if (opts->transport_retry_count > NVME_RDMA_CTRLR_MAX_TRANSPORT_RETRY_COUNT) {
2135 		SPDK_NOTICELOG("transport_retry_count exceeds max value %d, use max value\n",
2136 			       NVME_RDMA_CTRLR_MAX_TRANSPORT_RETRY_COUNT);
2137 		rctrlr->ctrlr.opts.transport_retry_count = NVME_RDMA_CTRLR_MAX_TRANSPORT_RETRY_COUNT;
2138 	}
2139 
2140 	if (opts->transport_ack_timeout > NVME_RDMA_CTRLR_MAX_TRANSPORT_ACK_TIMEOUT) {
2141 		SPDK_NOTICELOG("transport_ack_timeout exceeds max value %d, use max value\n",
2142 			       NVME_RDMA_CTRLR_MAX_TRANSPORT_ACK_TIMEOUT);
2143 		rctrlr->ctrlr.opts.transport_ack_timeout = NVME_RDMA_CTRLR_MAX_TRANSPORT_ACK_TIMEOUT;
2144 	}
2145 
2146 	contexts = rdma_get_devices(NULL);
2147 	if (contexts == NULL) {
2148 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2149 		spdk_free(rctrlr);
2150 		return NULL;
2151 	}
2152 
2153 	i = 0;
2154 	rctrlr->max_sge = NVME_RDMA_MAX_SGL_DESCRIPTORS;
2155 
2156 	while (contexts[i] != NULL) {
2157 		rc = ibv_query_device(contexts[i], &dev_attr);
2158 		if (rc < 0) {
2159 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2160 			rdma_free_devices(contexts);
2161 			spdk_free(rctrlr);
2162 			return NULL;
2163 		}
2164 		rctrlr->max_sge = spdk_min(rctrlr->max_sge, (uint16_t)dev_attr.max_sge);
2165 		i++;
2166 	}
2167 
2168 	rdma_free_devices(contexts);
2169 
2170 	rc = nvme_ctrlr_construct(&rctrlr->ctrlr);
2171 	if (rc != 0) {
2172 		spdk_free(rctrlr);
2173 		return NULL;
2174 	}
2175 
2176 	STAILQ_INIT(&rctrlr->pending_cm_events);
2177 	STAILQ_INIT(&rctrlr->free_cm_events);
2178 	rctrlr->cm_events = spdk_zmalloc(NVME_RDMA_NUM_CM_EVENTS * sizeof(*rctrlr->cm_events), 0, NULL,
2179 					 SPDK_ENV_NUMA_ID_ANY, SPDK_MALLOC_DMA);
2180 	if (rctrlr->cm_events == NULL) {
2181 		SPDK_ERRLOG("unable to allocate buffers to hold CM events.\n");
2182 		goto destruct_ctrlr;
2183 	}
2184 
2185 	for (i = 0; i < NVME_RDMA_NUM_CM_EVENTS; i++) {
2186 		STAILQ_INSERT_TAIL(&rctrlr->free_cm_events, &rctrlr->cm_events[i], link);
2187 	}
2188 
2189 	rctrlr->cm_channel = rdma_create_event_channel();
2190 	if (rctrlr->cm_channel == NULL) {
2191 		SPDK_ERRLOG("rdma_create_event_channel() failed\n");
2192 		goto destruct_ctrlr;
2193 	}
2194 
2195 	flag = fcntl(rctrlr->cm_channel->fd, F_GETFL);
2196 	if (fcntl(rctrlr->cm_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2197 		SPDK_ERRLOG("Cannot set event channel to non blocking\n");
2198 		goto destruct_ctrlr;
2199 	}
2200 
2201 	rctrlr->ctrlr.adminq = nvme_rdma_ctrlr_create_qpair(&rctrlr->ctrlr, 0,
2202 			       rctrlr->ctrlr.opts.admin_queue_size, 0,
2203 			       rctrlr->ctrlr.opts.admin_queue_size, false, true);
2204 	if (!rctrlr->ctrlr.adminq) {
2205 		SPDK_ERRLOG("failed to create admin qpair\n");
2206 		goto destruct_ctrlr;
2207 	}
2208 
2209 	if (nvme_ctrlr_add_process(&rctrlr->ctrlr, 0) != 0) {
2210 		SPDK_ERRLOG("nvme_ctrlr_add_process() failed\n");
2211 		goto destruct_ctrlr;
2212 	}
2213 
2214 	SPDK_DEBUGLOG(nvme, "successfully initialized the nvmf ctrlr\n");
2215 	return &rctrlr->ctrlr;
2216 
2217 destruct_ctrlr:
2218 	nvme_ctrlr_destruct(&rctrlr->ctrlr);
2219 	return NULL;
2220 }
2221 
2222 static int
2223 nvme_rdma_ctrlr_destruct(struct spdk_nvme_ctrlr *ctrlr)
2224 {
2225 	struct nvme_rdma_ctrlr *rctrlr = nvme_rdma_ctrlr(ctrlr);
2226 	struct nvme_rdma_cm_event_entry *entry;
2227 
2228 	if (ctrlr->adminq) {
2229 		nvme_rdma_ctrlr_delete_io_qpair(ctrlr, ctrlr->adminq);
2230 	}
2231 
2232 	STAILQ_FOREACH(entry, &rctrlr->pending_cm_events, link) {
2233 		rdma_ack_cm_event(entry->evt);
2234 	}
2235 
2236 	STAILQ_INIT(&rctrlr->free_cm_events);
2237 	STAILQ_INIT(&rctrlr->pending_cm_events);
2238 	spdk_free(rctrlr->cm_events);
2239 
2240 	if (rctrlr->cm_channel) {
2241 		rdma_destroy_event_channel(rctrlr->cm_channel);
2242 		rctrlr->cm_channel = NULL;
2243 	}
2244 
2245 	nvme_ctrlr_destruct_finish(ctrlr);
2246 
2247 	spdk_free(rctrlr);
2248 
2249 	return 0;
2250 }
2251 
2252 static int
2253 nvme_rdma_qpair_submit_request(struct spdk_nvme_qpair *qpair,
2254 			       struct nvme_request *req)
2255 {
2256 	struct nvme_rdma_qpair *rqpair;
2257 	struct spdk_nvme_rdma_req *rdma_req;
2258 	struct ibv_send_wr *wr;
2259 	struct nvme_rdma_poll_group *group;
2260 
2261 	rqpair = nvme_rdma_qpair(qpair);
2262 	assert(rqpair != NULL);
2263 	assert(req != NULL);
2264 
2265 	rdma_req = nvme_rdma_req_get(rqpair);
2266 	if (spdk_unlikely(!rdma_req)) {
2267 		if (rqpair->poller) {
2268 			rqpair->poller->stats.queued_requests++;
2269 		}
2270 		/* Inform the upper layer to try again later. */
2271 		return -EAGAIN;
2272 	}
2273 
2274 	if (nvme_rdma_req_init(rqpair, req, rdma_req)) {
2275 		SPDK_ERRLOG("nvme_rdma_req_init() failed\n");
2276 		nvme_rdma_req_put(rqpair, rdma_req);
2277 		return -1;
2278 	}
2279 
2280 	TAILQ_INSERT_TAIL(&rqpair->outstanding_reqs, rdma_req, link);
2281 
2282 	if (!rqpair->link_active.tqe_prev && qpair->poll_group) {
2283 		group = nvme_rdma_poll_group(qpair->poll_group);
2284 		TAILQ_INSERT_TAIL(&group->active_qpairs, rqpair, link_active);
2285 	}
2286 	rqpair->num_outstanding_reqs++;
2287 
2288 	assert(rqpair->current_num_sends < rqpair->num_entries);
2289 	rqpair->current_num_sends++;
2290 
2291 	wr = &rdma_req->send_wr;
2292 	wr->next = NULL;
2293 	nvme_rdma_trace_ibv_sge(wr->sg_list);
2294 
2295 	spdk_rdma_provider_qp_queue_send_wrs(rqpair->rdma_qp, wr);
2296 
2297 	if (!rqpair->delay_cmd_submit) {
2298 		return nvme_rdma_qpair_submit_sends(rqpair);
2299 	}
2300 
2301 	return 0;
2302 }
2303 
2304 static int
2305 nvme_rdma_qpair_reset(struct spdk_nvme_qpair *qpair)
2306 {
2307 	/* Currently, doing nothing here */
2308 	return 0;
2309 }
2310 
2311 static void
2312 nvme_rdma_qpair_abort_reqs(struct spdk_nvme_qpair *qpair, uint32_t dnr)
2313 {
2314 	struct spdk_nvme_rdma_req *rdma_req, *tmp;
2315 	struct spdk_nvme_cpl cpl;
2316 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
2317 
2318 	cpl.sqid = qpair->id;
2319 	cpl.status.sc = SPDK_NVME_SC_ABORTED_SQ_DELETION;
2320 	cpl.status.sct = SPDK_NVME_SCT_GENERIC;
2321 	cpl.status.dnr = dnr;
2322 
2323 	/*
2324 	 * We cannot abort requests at the RDMA layer without
2325 	 * unregistering them. If we do, we can still get error
2326 	 * free completions on the shared completion queue.
2327 	 */
2328 	if (nvme_qpair_get_state(qpair) > NVME_QPAIR_DISCONNECTING &&
2329 	    nvme_qpair_get_state(qpair) != NVME_QPAIR_DESTROYING) {
2330 		nvme_ctrlr_disconnect_qpair(qpair);
2331 	}
2332 
2333 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->outstanding_reqs, link, tmp) {
2334 		nvme_rdma_req_complete(rdma_req, &cpl, true);
2335 	}
2336 }
2337 
2338 static void
2339 nvme_rdma_qpair_check_timeout(struct spdk_nvme_qpair *qpair)
2340 {
2341 	uint64_t t02;
2342 	struct spdk_nvme_rdma_req *rdma_req, *tmp;
2343 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
2344 	struct spdk_nvme_ctrlr *ctrlr = qpair->ctrlr;
2345 	struct spdk_nvme_ctrlr_process *active_proc;
2346 
2347 	/* Don't check timeouts during controller initialization. */
2348 	if (ctrlr->state != NVME_CTRLR_STATE_READY) {
2349 		return;
2350 	}
2351 
2352 	if (nvme_qpair_is_admin_queue(qpair)) {
2353 		active_proc = nvme_ctrlr_get_current_process(ctrlr);
2354 	} else {
2355 		active_proc = qpair->active_proc;
2356 	}
2357 
2358 	/* Only check timeouts if the current process has a timeout callback. */
2359 	if (active_proc == NULL || active_proc->timeout_cb_fn == NULL) {
2360 		return;
2361 	}
2362 
2363 	t02 = spdk_get_ticks();
2364 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->outstanding_reqs, link, tmp) {
2365 		assert(rdma_req->req != NULL);
2366 
2367 		if (nvme_request_check_timeout(rdma_req->req, rdma_req->id, active_proc, t02)) {
2368 			/*
2369 			 * The requests are in order, so as soon as one has not timed out,
2370 			 * stop iterating.
2371 			 */
2372 			break;
2373 		}
2374 	}
2375 }
2376 
2377 static inline void
2378 nvme_rdma_request_ready(struct nvme_rdma_qpair *rqpair, struct spdk_nvme_rdma_req *rdma_req)
2379 {
2380 	struct spdk_nvme_rdma_rsp *rdma_rsp = rdma_req->rdma_rsp;
2381 	struct ibv_recv_wr *recv_wr = rdma_rsp->recv_wr;
2382 
2383 	nvme_rdma_req_complete(rdma_req, &rdma_rsp->cpl, true);
2384 
2385 	assert(rqpair->rsps->current_num_recvs < rqpair->rsps->num_entries);
2386 	rqpair->rsps->current_num_recvs++;
2387 
2388 	recv_wr->next = NULL;
2389 	nvme_rdma_trace_ibv_sge(recv_wr->sg_list);
2390 
2391 	if (!rqpair->srq) {
2392 		spdk_rdma_provider_qp_queue_recv_wrs(rqpair->rdma_qp, recv_wr);
2393 	} else {
2394 		spdk_rdma_provider_srq_queue_recv_wrs(rqpair->srq, recv_wr);
2395 	}
2396 }
2397 
2398 #define MAX_COMPLETIONS_PER_POLL 128
2399 
2400 static void
2401 nvme_rdma_fail_qpair(struct spdk_nvme_qpair *qpair, int failure_reason)
2402 {
2403 	if (failure_reason == IBV_WC_RETRY_EXC_ERR) {
2404 		qpair->transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_REMOTE;
2405 	} else if (qpair->transport_failure_reason == SPDK_NVME_QPAIR_FAILURE_NONE) {
2406 		qpair->transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_UNKNOWN;
2407 	}
2408 
2409 	nvme_ctrlr_disconnect_qpair(qpair);
2410 }
2411 
2412 static struct nvme_rdma_qpair *
2413 get_rdma_qpair_from_wc(struct nvme_rdma_poll_group *group, struct ibv_wc *wc)
2414 {
2415 	struct spdk_nvme_qpair *qpair;
2416 	struct nvme_rdma_qpair *rqpair;
2417 
2418 	STAILQ_FOREACH(qpair, &group->group.connected_qpairs, poll_group_stailq) {
2419 		rqpair = nvme_rdma_qpair(qpair);
2420 		if (NVME_RDMA_POLL_GROUP_CHECK_QPN(rqpair, wc->qp_num)) {
2421 			return rqpair;
2422 		}
2423 	}
2424 
2425 	STAILQ_FOREACH(qpair, &group->group.disconnected_qpairs, poll_group_stailq) {
2426 		rqpair = nvme_rdma_qpair(qpair);
2427 		if (NVME_RDMA_POLL_GROUP_CHECK_QPN(rqpair, wc->qp_num)) {
2428 			return rqpair;
2429 		}
2430 	}
2431 
2432 	return NULL;
2433 }
2434 
2435 static inline void
2436 nvme_rdma_log_wc_status(struct nvme_rdma_qpair *rqpair, struct ibv_wc *wc)
2437 {
2438 	struct nvme_rdma_wr *rdma_wr = (struct nvme_rdma_wr *)wc->wr_id;
2439 
2440 	if (wc->status == IBV_WC_WR_FLUSH_ERR) {
2441 		/* If qpair is in ERR state, we will receive completions for all posted and not completed
2442 		 * Work Requests with IBV_WC_WR_FLUSH_ERR status. Don't log an error in that case */
2443 		SPDK_DEBUGLOG(nvme, "WC error, qid %u, qp state %d, request 0x%lu type %d, status: (%d): %s\n",
2444 			      rqpair->qpair.id, rqpair->qpair.state, wc->wr_id, rdma_wr->type, wc->status,
2445 			      ibv_wc_status_str(wc->status));
2446 	} else {
2447 		SPDK_ERRLOG("WC error, qid %u, qp state %d, request 0x%lu type %d, status: (%d): %s\n",
2448 			    rqpair->qpair.id, rqpair->qpair.state, wc->wr_id, rdma_wr->type, wc->status,
2449 			    ibv_wc_status_str(wc->status));
2450 	}
2451 }
2452 
2453 static inline int
2454 nvme_rdma_process_recv_completion(struct nvme_rdma_poller *poller, struct ibv_wc *wc,
2455 				  struct nvme_rdma_wr *rdma_wr)
2456 {
2457 	struct nvme_rdma_qpair		*rqpair;
2458 	struct spdk_nvme_rdma_req	*rdma_req;
2459 	struct spdk_nvme_rdma_rsp	*rdma_rsp;
2460 
2461 	rdma_rsp = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvme_rdma_rsp, rdma_wr);
2462 
2463 	if (poller && poller->srq) {
2464 		rqpair = get_rdma_qpair_from_wc(poller->group, wc);
2465 		if (spdk_unlikely(!rqpair)) {
2466 			/* Since we do not handle the LAST_WQE_REACHED event, we do not know when
2467 			 * a Receive Queue in a QP, that is associated with an SRQ, is flushed.
2468 			 * We may get a WC for a already destroyed QP.
2469 			 *
2470 			 * However, for the SRQ, this is not any error. Hence, just re-post the
2471 			 * receive request to the SRQ to reuse for other QPs, and return 0.
2472 			 */
2473 			spdk_rdma_provider_srq_queue_recv_wrs(poller->srq, rdma_rsp->recv_wr);
2474 			return 0;
2475 		}
2476 	} else {
2477 		rqpair = rdma_rsp->rqpair;
2478 		if (spdk_unlikely(!rqpair)) {
2479 			/* TODO: Fix forceful QP destroy when it is not async mode.
2480 			 * CQ itself did not cause any error. Hence, return 0 for now.
2481 			 */
2482 			SPDK_WARNLOG("QP might be already destroyed.\n");
2483 			return 0;
2484 		}
2485 	}
2486 
2487 
2488 	assert(rqpair->rsps->current_num_recvs > 0);
2489 	rqpair->rsps->current_num_recvs--;
2490 
2491 	if (wc->status) {
2492 		nvme_rdma_log_wc_status(rqpair, wc);
2493 		goto err_wc;
2494 	}
2495 
2496 	SPDK_DEBUGLOG(nvme, "CQ recv completion\n");
2497 
2498 	if (wc->byte_len < sizeof(struct spdk_nvme_cpl)) {
2499 		SPDK_ERRLOG("recv length %u less than expected response size\n", wc->byte_len);
2500 		goto err_wc;
2501 	}
2502 	rdma_req = &rqpair->rdma_reqs[rdma_rsp->cpl.cid];
2503 	rdma_req->completion_flags |= NVME_RDMA_RECV_COMPLETED;
2504 	rdma_req->rdma_rsp = rdma_rsp;
2505 
2506 	if ((rdma_req->completion_flags & NVME_RDMA_SEND_COMPLETED) == 0) {
2507 		return 0;
2508 	}
2509 
2510 	rqpair->num_completions++;
2511 
2512 	nvme_rdma_request_ready(rqpair, rdma_req);
2513 
2514 	if (!rqpair->delay_cmd_submit) {
2515 		if (spdk_unlikely(nvme_rdma_qpair_submit_recvs(rqpair))) {
2516 			SPDK_ERRLOG("Unable to re-post rx descriptor\n");
2517 			nvme_rdma_fail_qpair(&rqpair->qpair, 0);
2518 			return -ENXIO;
2519 		}
2520 	}
2521 
2522 	return 1;
2523 
2524 err_wc:
2525 	nvme_rdma_fail_qpair(&rqpair->qpair, 0);
2526 	if (poller && poller->srq) {
2527 		spdk_rdma_provider_srq_queue_recv_wrs(poller->srq, rdma_rsp->recv_wr);
2528 	}
2529 	return -ENXIO;
2530 }
2531 
2532 static inline int
2533 nvme_rdma_process_send_completion(struct nvme_rdma_poller *poller,
2534 				  struct nvme_rdma_qpair *rdma_qpair,
2535 				  struct ibv_wc *wc, struct nvme_rdma_wr *rdma_wr)
2536 {
2537 	struct nvme_rdma_qpair		*rqpair;
2538 	struct spdk_nvme_rdma_req	*rdma_req;
2539 
2540 	rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvme_rdma_req, rdma_wr);
2541 	rqpair = rdma_req->req ? nvme_rdma_qpair(rdma_req->req->qpair) : NULL;
2542 	if (!rqpair) {
2543 		rqpair = rdma_qpair != NULL ? rdma_qpair : get_rdma_qpair_from_wc(poller->group, wc);
2544 	}
2545 
2546 	/* If we are flushing I/O */
2547 	if (wc->status) {
2548 		if (!rqpair) {
2549 			/* When poll_group is used, several qpairs share the same CQ and it is possible to
2550 			 * receive a completion with error (e.g. IBV_WC_WR_FLUSH_ERR) for already disconnected qpair
2551 			 * That happens due to qpair is destroyed while there are submitted but not completed send/receive
2552 			 * Work Requests */
2553 			assert(poller);
2554 			return 0;
2555 		}
2556 		assert(rqpair->current_num_sends > 0);
2557 		rqpair->current_num_sends--;
2558 		nvme_rdma_log_wc_status(rqpair, wc);
2559 		nvme_rdma_fail_qpair(&rqpair->qpair, 0);
2560 		if (rdma_req->rdma_rsp && poller && poller->srq) {
2561 			spdk_rdma_provider_srq_queue_recv_wrs(poller->srq, rdma_req->rdma_rsp->recv_wr);
2562 		}
2563 		return -ENXIO;
2564 	}
2565 
2566 	/* We do not support Soft Roce anymore. Other than Soft Roce's bug, we should not
2567 	 * receive a completion without error status after qpair is disconnected/destroyed.
2568 	 */
2569 	if (spdk_unlikely(rdma_req->req == NULL)) {
2570 		/*
2571 		 * Some infiniband drivers do not guarantee the previous assumption after we
2572 		 * received a RDMA_CM_EVENT_DEVICE_REMOVAL event.
2573 		 */
2574 		SPDK_ERRLOG("Received malformed completion: request 0x%"PRIx64" type %d\n", wc->wr_id,
2575 			    rdma_wr->type);
2576 		if (!rqpair || !rqpair->need_destroy) {
2577 			assert(0);
2578 		}
2579 		return -ENXIO;
2580 	}
2581 
2582 	rdma_req->completion_flags |= NVME_RDMA_SEND_COMPLETED;
2583 	assert(rqpair->current_num_sends > 0);
2584 	rqpair->current_num_sends--;
2585 
2586 	if ((rdma_req->completion_flags & NVME_RDMA_RECV_COMPLETED) == 0) {
2587 		return 0;
2588 	}
2589 
2590 	rqpair->num_completions++;
2591 
2592 	nvme_rdma_request_ready(rqpair, rdma_req);
2593 
2594 	if (!rqpair->delay_cmd_submit) {
2595 		if (spdk_unlikely(nvme_rdma_qpair_submit_recvs(rqpair))) {
2596 			SPDK_ERRLOG("Unable to re-post rx descriptor\n");
2597 			nvme_rdma_fail_qpair(&rqpair->qpair, 0);
2598 			return -ENXIO;
2599 		}
2600 	}
2601 
2602 	return 1;
2603 }
2604 
2605 static int
2606 nvme_rdma_cq_process_completions(struct ibv_cq *cq, uint32_t batch_size,
2607 				 struct nvme_rdma_poller *poller,
2608 				 struct nvme_rdma_qpair *rdma_qpair,
2609 				 uint64_t *rdma_completions)
2610 {
2611 	struct ibv_wc			wc[MAX_COMPLETIONS_PER_POLL];
2612 	struct nvme_rdma_wr		*rdma_wr;
2613 	uint32_t			reaped = 0;
2614 	int				completion_rc = 0;
2615 	int				rc, _rc, i;
2616 
2617 	rc = ibv_poll_cq(cq, batch_size, wc);
2618 	if (rc < 0) {
2619 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
2620 			    errno, spdk_strerror(errno));
2621 		return -ECANCELED;
2622 	} else if (rc == 0) {
2623 		return 0;
2624 	}
2625 
2626 	for (i = 0; i < rc; i++) {
2627 		rdma_wr = (struct nvme_rdma_wr *)wc[i].wr_id;
2628 		switch (rdma_wr->type) {
2629 		case RDMA_WR_TYPE_RECV:
2630 			_rc = nvme_rdma_process_recv_completion(poller, &wc[i], rdma_wr);
2631 			break;
2632 
2633 		case RDMA_WR_TYPE_SEND:
2634 			_rc = nvme_rdma_process_send_completion(poller, rdma_qpair, &wc[i], rdma_wr);
2635 			break;
2636 
2637 		default:
2638 			SPDK_ERRLOG("Received an unexpected opcode on the CQ: %d\n", rdma_wr->type);
2639 			return -ECANCELED;
2640 		}
2641 		if (spdk_likely(_rc >= 0)) {
2642 			reaped += _rc;
2643 		} else {
2644 			completion_rc = _rc;
2645 		}
2646 	}
2647 
2648 	*rdma_completions += rc;
2649 
2650 	if (completion_rc) {
2651 		return completion_rc;
2652 	}
2653 
2654 	return reaped;
2655 }
2656 
2657 static void
2658 dummy_disconnected_qpair_cb(struct spdk_nvme_qpair *qpair, void *poll_group_ctx)
2659 {
2660 
2661 }
2662 
2663 static int
2664 nvme_rdma_qpair_process_completions(struct spdk_nvme_qpair *qpair,
2665 				    uint32_t max_completions)
2666 {
2667 	struct nvme_rdma_qpair		*rqpair = nvme_rdma_qpair(qpair);
2668 	struct nvme_rdma_ctrlr		*rctrlr = nvme_rdma_ctrlr(qpair->ctrlr);
2669 	int				rc = 0, batch_size;
2670 	struct ibv_cq			*cq;
2671 	uint64_t			rdma_completions = 0;
2672 
2673 	/*
2674 	 * This is used during the connection phase. It's possible that we are still reaping error completions
2675 	 * from other qpairs so we need to call the poll group function. Also, it's more correct since the cq
2676 	 * is shared.
2677 	 */
2678 	if (qpair->poll_group != NULL) {
2679 		return spdk_nvme_poll_group_process_completions(qpair->poll_group->group, max_completions,
2680 				dummy_disconnected_qpair_cb);
2681 	}
2682 
2683 	if (max_completions == 0) {
2684 		max_completions = rqpair->num_entries;
2685 	} else {
2686 		max_completions = spdk_min(max_completions, rqpair->num_entries);
2687 	}
2688 
2689 	switch (nvme_qpair_get_state(qpair)) {
2690 	case NVME_QPAIR_CONNECTING:
2691 		rc = nvme_rdma_ctrlr_connect_qpair_poll(qpair->ctrlr, qpair);
2692 		if (rc == 0) {
2693 			/* Once the connection is completed, we can submit queued requests */
2694 			nvme_qpair_resubmit_requests(qpair, rqpair->num_entries);
2695 		} else if (rc != -EAGAIN) {
2696 			SPDK_ERRLOG("Failed to connect rqpair=%p\n", rqpair);
2697 			goto failed;
2698 		} else if (rqpair->state <= NVME_RDMA_QPAIR_STATE_INITIALIZING) {
2699 			return 0;
2700 		}
2701 		break;
2702 
2703 	case NVME_QPAIR_DISCONNECTING:
2704 		nvme_rdma_ctrlr_disconnect_qpair_poll(qpair->ctrlr, qpair);
2705 		return -ENXIO;
2706 
2707 	default:
2708 		if (nvme_qpair_is_admin_queue(qpair)) {
2709 			nvme_rdma_poll_events(rctrlr);
2710 		}
2711 		nvme_rdma_qpair_process_cm_event(rqpair);
2712 		break;
2713 	}
2714 
2715 	if (spdk_unlikely(qpair->transport_failure_reason != SPDK_NVME_QPAIR_FAILURE_NONE)) {
2716 		goto failed;
2717 	}
2718 
2719 	cq = rqpair->cq;
2720 
2721 	rqpair->num_completions = 0;
2722 	do {
2723 		batch_size = spdk_min((max_completions - rqpair->num_completions), MAX_COMPLETIONS_PER_POLL);
2724 		rc = nvme_rdma_cq_process_completions(cq, batch_size, NULL, rqpair, &rdma_completions);
2725 
2726 		if (rc == 0) {
2727 			break;
2728 			/* Handle the case where we fail to poll the cq. */
2729 		} else if (rc == -ECANCELED) {
2730 			goto failed;
2731 		} else if (rc == -ENXIO) {
2732 			return rc;
2733 		}
2734 	} while (rqpair->num_completions < max_completions);
2735 
2736 	if (spdk_unlikely(nvme_rdma_qpair_submit_sends(rqpair) ||
2737 			  nvme_rdma_qpair_submit_recvs(rqpair))) {
2738 		goto failed;
2739 	}
2740 
2741 	if (spdk_unlikely(qpair->ctrlr->timeout_enabled)) {
2742 		nvme_rdma_qpair_check_timeout(qpair);
2743 	}
2744 
2745 	return rqpair->num_completions;
2746 
2747 failed:
2748 	nvme_rdma_fail_qpair(qpair, 0);
2749 	return -ENXIO;
2750 }
2751 
2752 static uint32_t
2753 nvme_rdma_ctrlr_get_max_xfer_size(struct spdk_nvme_ctrlr *ctrlr)
2754 {
2755 	/* max_mr_size by ibv_query_device indicates the largest value that we can
2756 	 * set for a registered memory region.  It is independent from the actual
2757 	 * I/O size and is very likely to be larger than 2 MiB which is the
2758 	 * granularity we currently register memory regions.  Hence return
2759 	 * UINT32_MAX here and let the generic layer use the controller data to
2760 	 * moderate this value.
2761 	 */
2762 	return UINT32_MAX;
2763 }
2764 
2765 static uint16_t
2766 nvme_rdma_ctrlr_get_max_sges(struct spdk_nvme_ctrlr *ctrlr)
2767 {
2768 	struct nvme_rdma_ctrlr *rctrlr = nvme_rdma_ctrlr(ctrlr);
2769 	uint32_t max_sge = rctrlr->max_sge;
2770 	uint32_t max_in_capsule_sge = (ctrlr->cdata.nvmf_specific.ioccsz * 16 -
2771 				       sizeof(struct spdk_nvme_cmd)) /
2772 				      sizeof(struct spdk_nvme_sgl_descriptor);
2773 
2774 	/* Max SGE is limited by capsule size */
2775 	max_sge = spdk_min(max_sge, max_in_capsule_sge);
2776 	/* Max SGE may be limited by MSDBD */
2777 	if (ctrlr->cdata.nvmf_specific.msdbd != 0) {
2778 		max_sge = spdk_min(max_sge, ctrlr->cdata.nvmf_specific.msdbd);
2779 	}
2780 
2781 	/* Max SGE can't be less than 1 */
2782 	max_sge = spdk_max(1, max_sge);
2783 	return max_sge;
2784 }
2785 
2786 static int
2787 nvme_rdma_qpair_iterate_requests(struct spdk_nvme_qpair *qpair,
2788 				 int (*iter_fn)(struct nvme_request *req, void *arg),
2789 				 void *arg)
2790 {
2791 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
2792 	struct spdk_nvme_rdma_req *rdma_req, *tmp;
2793 	int rc;
2794 
2795 	assert(iter_fn != NULL);
2796 
2797 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->outstanding_reqs, link, tmp) {
2798 		assert(rdma_req->req != NULL);
2799 
2800 		rc = iter_fn(rdma_req->req, arg);
2801 		if (rc != 0) {
2802 			return rc;
2803 		}
2804 	}
2805 
2806 	return 0;
2807 }
2808 
2809 static int
2810 nvme_rdma_qpair_authenticate(struct spdk_nvme_qpair *qpair)
2811 {
2812 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
2813 	int rc;
2814 
2815 	/* If the qpair is still connecting, it'll be forced to authenticate later on */
2816 	if (rqpair->state < NVME_RDMA_QPAIR_STATE_RUNNING) {
2817 		return 0;
2818 	} else if (rqpair->state != NVME_RDMA_QPAIR_STATE_RUNNING) {
2819 		return -ENOTCONN;
2820 	}
2821 
2822 	rc = nvme_fabric_qpair_authenticate_async(qpair);
2823 	if (rc == 0) {
2824 		nvme_qpair_set_state(qpair, NVME_QPAIR_CONNECTING);
2825 		rqpair->state = NVME_RDMA_QPAIR_STATE_AUTHENTICATING;
2826 	}
2827 
2828 	return rc;
2829 }
2830 
2831 static void
2832 nvme_rdma_admin_qpair_abort_aers(struct spdk_nvme_qpair *qpair)
2833 {
2834 	struct spdk_nvme_rdma_req *rdma_req, *tmp;
2835 	struct spdk_nvme_cpl cpl;
2836 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
2837 
2838 	cpl.status.sc = SPDK_NVME_SC_ABORTED_SQ_DELETION;
2839 	cpl.status.sct = SPDK_NVME_SCT_GENERIC;
2840 
2841 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->outstanding_reqs, link, tmp) {
2842 		assert(rdma_req->req != NULL);
2843 
2844 		if (rdma_req->req->cmd.opc != SPDK_NVME_OPC_ASYNC_EVENT_REQUEST) {
2845 			continue;
2846 		}
2847 
2848 		nvme_rdma_req_complete(rdma_req, &cpl, false);
2849 	}
2850 }
2851 
2852 static void
2853 nvme_rdma_poller_destroy(struct nvme_rdma_poller *poller)
2854 {
2855 	if (poller->cq) {
2856 		ibv_destroy_cq(poller->cq);
2857 	}
2858 	if (poller->rsps) {
2859 		nvme_rdma_free_rsps(poller->rsps);
2860 	}
2861 	if (poller->srq) {
2862 		spdk_rdma_provider_srq_destroy(poller->srq);
2863 	}
2864 	if (poller->mr_map) {
2865 		spdk_rdma_utils_free_mem_map(&poller->mr_map);
2866 	}
2867 	if (poller->pd) {
2868 		spdk_rdma_utils_put_pd(poller->pd);
2869 	}
2870 	free(poller);
2871 }
2872 
2873 static struct nvme_rdma_poller *
2874 nvme_rdma_poller_create(struct nvme_rdma_poll_group *group, struct ibv_context *ctx)
2875 {
2876 	struct nvme_rdma_poller *poller;
2877 	struct ibv_device_attr dev_attr;
2878 	struct spdk_rdma_provider_srq_init_attr srq_init_attr = {};
2879 	struct nvme_rdma_rsp_opts opts;
2880 	int num_cqe, max_num_cqe;
2881 	int rc;
2882 
2883 	poller = calloc(1, sizeof(*poller));
2884 	if (poller == NULL) {
2885 		SPDK_ERRLOG("Unable to allocate poller.\n");
2886 		return NULL;
2887 	}
2888 
2889 	poller->group = group;
2890 	poller->device = ctx;
2891 
2892 	if (g_spdk_nvme_transport_opts.rdma_srq_size != 0) {
2893 		rc = ibv_query_device(ctx, &dev_attr);
2894 		if (rc) {
2895 			SPDK_ERRLOG("Unable to query RDMA device.\n");
2896 			goto fail;
2897 		}
2898 
2899 		poller->pd = spdk_rdma_utils_get_pd(ctx);
2900 		if (poller->pd == NULL) {
2901 			SPDK_ERRLOG("Unable to get PD.\n");
2902 			goto fail;
2903 		}
2904 
2905 		poller->mr_map = spdk_rdma_utils_create_mem_map(poller->pd, &g_nvme_hooks,
2906 				 IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_READ | IBV_ACCESS_REMOTE_WRITE);
2907 		if (poller->mr_map == NULL) {
2908 			SPDK_ERRLOG("Unable to create memory map.\n");
2909 			goto fail;
2910 		}
2911 
2912 		srq_init_attr.stats = &poller->stats.rdma_stats.recv;
2913 		srq_init_attr.pd = poller->pd;
2914 		srq_init_attr.srq_init_attr.attr.max_wr = spdk_min((uint32_t)dev_attr.max_srq_wr,
2915 				g_spdk_nvme_transport_opts.rdma_srq_size);
2916 		srq_init_attr.srq_init_attr.attr.max_sge = spdk_min(dev_attr.max_sge,
2917 				NVME_RDMA_DEFAULT_RX_SGE);
2918 
2919 		poller->srq = spdk_rdma_provider_srq_create(&srq_init_attr);
2920 		if (poller->srq == NULL) {
2921 			SPDK_ERRLOG("Unable to create SRQ.\n");
2922 			goto fail;
2923 		}
2924 
2925 		opts.num_entries = g_spdk_nvme_transport_opts.rdma_srq_size;
2926 		opts.rqpair = NULL;
2927 		opts.srq = poller->srq;
2928 		opts.mr_map = poller->mr_map;
2929 
2930 		poller->rsps = nvme_rdma_create_rsps(&opts);
2931 		if (poller->rsps == NULL) {
2932 			SPDK_ERRLOG("Unable to create poller RDMA responses.\n");
2933 			goto fail;
2934 		}
2935 
2936 		rc = nvme_rdma_poller_submit_recvs(poller);
2937 		if (rc) {
2938 			SPDK_ERRLOG("Unable to submit poller RDMA responses.\n");
2939 			goto fail;
2940 		}
2941 
2942 		/*
2943 		 * When using an srq, fix the size of the completion queue at startup.
2944 		 * The initiator sends only send and recv WRs. Hence, the multiplier is 2.
2945 		 * (The target sends also data WRs. Hence, the multiplier is 3.)
2946 		 */
2947 		num_cqe = g_spdk_nvme_transport_opts.rdma_srq_size * 2;
2948 	} else {
2949 		num_cqe = DEFAULT_NVME_RDMA_CQ_SIZE;
2950 	}
2951 
2952 	max_num_cqe = g_spdk_nvme_transport_opts.rdma_max_cq_size;
2953 	if (max_num_cqe != 0 && num_cqe > max_num_cqe) {
2954 		num_cqe = max_num_cqe;
2955 	}
2956 
2957 	poller->cq = ibv_create_cq(poller->device, num_cqe, group, NULL, 0);
2958 
2959 	if (poller->cq == NULL) {
2960 		SPDK_ERRLOG("Unable to create CQ, errno %d.\n", errno);
2961 		goto fail;
2962 	}
2963 
2964 	STAILQ_INSERT_HEAD(&group->pollers, poller, link);
2965 	group->num_pollers++;
2966 	poller->current_num_wc = num_cqe;
2967 	poller->required_num_wc = 0;
2968 	return poller;
2969 
2970 fail:
2971 	nvme_rdma_poller_destroy(poller);
2972 	return NULL;
2973 }
2974 
2975 static void
2976 nvme_rdma_poll_group_free_pollers(struct nvme_rdma_poll_group *group)
2977 {
2978 	struct nvme_rdma_poller	*poller, *tmp_poller;
2979 
2980 	STAILQ_FOREACH_SAFE(poller, &group->pollers, link, tmp_poller) {
2981 		assert(poller->refcnt == 0);
2982 		if (poller->refcnt) {
2983 			SPDK_WARNLOG("Destroying poller with non-zero ref count: poller %p, refcnt %d\n",
2984 				     poller, poller->refcnt);
2985 		}
2986 
2987 		STAILQ_REMOVE(&group->pollers, poller, nvme_rdma_poller, link);
2988 		nvme_rdma_poller_destroy(poller);
2989 	}
2990 }
2991 
2992 static struct nvme_rdma_poller *
2993 nvme_rdma_poll_group_get_poller(struct nvme_rdma_poll_group *group, struct ibv_context *device)
2994 {
2995 	struct nvme_rdma_poller *poller = NULL;
2996 
2997 	STAILQ_FOREACH(poller, &group->pollers, link) {
2998 		if (poller->device == device) {
2999 			break;
3000 		}
3001 	}
3002 
3003 	if (!poller) {
3004 		poller = nvme_rdma_poller_create(group, device);
3005 		if (!poller) {
3006 			SPDK_ERRLOG("Failed to create a poller for device %p\n", device);
3007 			return NULL;
3008 		}
3009 	}
3010 
3011 	poller->refcnt++;
3012 	return poller;
3013 }
3014 
3015 static void
3016 nvme_rdma_poll_group_put_poller(struct nvme_rdma_poll_group *group, struct nvme_rdma_poller *poller)
3017 {
3018 	assert(poller->refcnt > 0);
3019 	if (--poller->refcnt == 0) {
3020 		STAILQ_REMOVE(&group->pollers, poller, nvme_rdma_poller, link);
3021 		group->num_pollers--;
3022 		nvme_rdma_poller_destroy(poller);
3023 	}
3024 }
3025 
3026 static struct spdk_nvme_transport_poll_group *
3027 nvme_rdma_poll_group_create(void)
3028 {
3029 	struct nvme_rdma_poll_group	*group;
3030 
3031 	group = calloc(1, sizeof(*group));
3032 	if (group == NULL) {
3033 		SPDK_ERRLOG("Unable to allocate poll group.\n");
3034 		return NULL;
3035 	}
3036 
3037 	STAILQ_INIT(&group->pollers);
3038 	TAILQ_INIT(&group->connecting_qpairs);
3039 	TAILQ_INIT(&group->active_qpairs);
3040 	return &group->group;
3041 }
3042 
3043 static int
3044 nvme_rdma_poll_group_connect_qpair(struct spdk_nvme_qpair *qpair)
3045 {
3046 	return 0;
3047 }
3048 
3049 static int
3050 nvme_rdma_poll_group_disconnect_qpair(struct spdk_nvme_qpair *qpair)
3051 {
3052 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
3053 	struct nvme_rdma_poll_group *group = nvme_rdma_poll_group(qpair->poll_group);
3054 
3055 	if (rqpair->link_connecting.tqe_prev) {
3056 		TAILQ_REMOVE(&group->connecting_qpairs, rqpair, link_connecting);
3057 		/* We use prev pointer to check if qpair is in connecting list or not .
3058 		 * TAILQ_REMOVE doesn't do it. So, we do it manually.
3059 		 */
3060 		rqpair->link_connecting.tqe_prev = NULL;
3061 	}
3062 
3063 	return 0;
3064 }
3065 
3066 static int
3067 nvme_rdma_poll_group_add(struct spdk_nvme_transport_poll_group *tgroup,
3068 			 struct spdk_nvme_qpair *qpair)
3069 {
3070 	return 0;
3071 }
3072 
3073 static int
3074 nvme_rdma_poll_group_remove(struct spdk_nvme_transport_poll_group *tgroup,
3075 			    struct spdk_nvme_qpair *qpair)
3076 {
3077 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(qpair);
3078 	struct nvme_rdma_poll_group *group = nvme_rdma_poll_group(qpair->poll_group);
3079 
3080 	if (rqpair->link_active.tqe_prev) {
3081 		TAILQ_REMOVE(&group->active_qpairs, rqpair, link_active);
3082 		rqpair->link_active.tqe_prev = NULL;
3083 	}
3084 
3085 	return 0;
3086 }
3087 
3088 static inline void
3089 nvme_rdma_qpair_process_submits(struct nvme_rdma_poll_group *group,
3090 				struct nvme_rdma_qpair *rqpair)
3091 {
3092 	struct spdk_nvme_qpair	*qpair = &rqpair->qpair;
3093 
3094 	assert(rqpair->link_active.tqe_prev != NULL);
3095 
3096 	if (spdk_unlikely(rqpair->state <= NVME_RDMA_QPAIR_STATE_INITIALIZING ||
3097 			  rqpair->state >= NVME_RDMA_QPAIR_STATE_EXITING)) {
3098 		return;
3099 	}
3100 
3101 	if (spdk_unlikely(qpair->ctrlr->timeout_enabled)) {
3102 		nvme_rdma_qpair_check_timeout(qpair);
3103 	}
3104 
3105 	nvme_rdma_qpair_submit_sends(rqpair);
3106 	if (!rqpair->srq) {
3107 		nvme_rdma_qpair_submit_recvs(rqpair);
3108 	}
3109 	if (rqpair->num_completions > 0) {
3110 		nvme_qpair_resubmit_requests(qpair, rqpair->num_completions);
3111 		rqpair->num_completions = 0;
3112 	}
3113 
3114 	if (rqpair->num_outstanding_reqs == 0 && STAILQ_EMPTY(&qpair->queued_req)) {
3115 		TAILQ_REMOVE(&group->active_qpairs, rqpair, link_active);
3116 		/* We use prev pointer to check if qpair is in active list or not.
3117 		 * TAILQ_REMOVE doesn't do it. So, we do it manually.
3118 		 */
3119 		rqpair->link_active.tqe_prev = NULL;
3120 	}
3121 }
3122 
3123 static int64_t
3124 nvme_rdma_poll_group_process_completions(struct spdk_nvme_transport_poll_group *tgroup,
3125 		uint32_t completions_per_qpair, spdk_nvme_disconnected_qpair_cb disconnected_qpair_cb)
3126 {
3127 	struct spdk_nvme_qpair			*qpair, *tmp_qpair;
3128 	struct nvme_rdma_qpair			*rqpair, *tmp_rqpair;
3129 	struct nvme_rdma_poll_group		*group;
3130 	struct nvme_rdma_poller			*poller;
3131 	int					batch_size, rc, rc2 = 0;
3132 	int64_t					total_completions = 0;
3133 	uint64_t				completions_allowed = 0;
3134 	uint64_t				completions_per_poller = 0;
3135 	uint64_t				poller_completions = 0;
3136 	uint64_t				rdma_completions;
3137 
3138 	if (completions_per_qpair == 0) {
3139 		completions_per_qpair = MAX_COMPLETIONS_PER_POLL;
3140 	}
3141 
3142 	group = nvme_rdma_poll_group(tgroup);
3143 
3144 	STAILQ_FOREACH_SAFE(qpair, &tgroup->disconnected_qpairs, poll_group_stailq, tmp_qpair) {
3145 		rc = nvme_rdma_ctrlr_disconnect_qpair_poll(qpair->ctrlr, qpair);
3146 		if (rc == 0) {
3147 			disconnected_qpair_cb(qpair, tgroup->group->ctx);
3148 		}
3149 	}
3150 
3151 	TAILQ_FOREACH_SAFE(rqpair, &group->connecting_qpairs, link_connecting, tmp_rqpair) {
3152 		qpair = &rqpair->qpair;
3153 
3154 		rc = nvme_rdma_ctrlr_connect_qpair_poll(qpair->ctrlr, qpair);
3155 		if (rc == 0 || rc != -EAGAIN) {
3156 			TAILQ_REMOVE(&group->connecting_qpairs, rqpair, link_connecting);
3157 			/* We use prev pointer to check if qpair is in connecting list or not.
3158 			 * TAILQ_REMOVE does not do it. So, we do it manually.
3159 			 */
3160 			rqpair->link_connecting.tqe_prev = NULL;
3161 
3162 			if (rc == 0) {
3163 				/* Once the connection is completed, we can submit queued requests */
3164 				nvme_qpair_resubmit_requests(qpair, rqpair->num_entries);
3165 			} else if (rc != -EAGAIN) {
3166 				SPDK_ERRLOG("Failed to connect rqpair=%p\n", rqpair);
3167 				nvme_rdma_fail_qpair(qpair, 0);
3168 			}
3169 		}
3170 	}
3171 
3172 	STAILQ_FOREACH_SAFE(qpair, &tgroup->connected_qpairs, poll_group_stailq, tmp_qpair) {
3173 		rqpair = nvme_rdma_qpair(qpair);
3174 
3175 		if (spdk_likely(nvme_qpair_get_state(qpair) != NVME_QPAIR_CONNECTING)) {
3176 			nvme_rdma_qpair_process_cm_event(rqpair);
3177 		}
3178 
3179 		if (spdk_unlikely(qpair->transport_failure_reason != SPDK_NVME_QPAIR_FAILURE_NONE)) {
3180 			rc2 = -ENXIO;
3181 			nvme_rdma_fail_qpair(qpair, 0);
3182 		}
3183 	}
3184 
3185 	completions_allowed = completions_per_qpair * tgroup->num_connected_qpairs;
3186 	if (group->num_pollers) {
3187 		completions_per_poller = spdk_max(completions_allowed / group->num_pollers, 1);
3188 	}
3189 
3190 	STAILQ_FOREACH(poller, &group->pollers, link) {
3191 		poller_completions = 0;
3192 		rdma_completions = 0;
3193 		do {
3194 			poller->stats.polls++;
3195 			batch_size = spdk_min((completions_per_poller - poller_completions), MAX_COMPLETIONS_PER_POLL);
3196 			rc = nvme_rdma_cq_process_completions(poller->cq, batch_size, poller, NULL, &rdma_completions);
3197 			if (rc <= 0) {
3198 				if (rc == -ECANCELED) {
3199 					return -EIO;
3200 				} else if (rc == 0) {
3201 					poller->stats.idle_polls++;
3202 				}
3203 				break;
3204 			}
3205 
3206 			poller_completions += rc;
3207 		} while (poller_completions < completions_per_poller);
3208 		total_completions += poller_completions;
3209 		poller->stats.completions += rdma_completions;
3210 		if (poller->srq) {
3211 			nvme_rdma_poller_submit_recvs(poller);
3212 		}
3213 	}
3214 
3215 	TAILQ_FOREACH_SAFE(rqpair, &group->active_qpairs, link_active, tmp_rqpair) {
3216 		nvme_rdma_qpair_process_submits(group, rqpair);
3217 	}
3218 
3219 	return rc2 != 0 ? rc2 : total_completions;
3220 }
3221 
3222 /*
3223  * Handle disconnected qpairs when interrupt support gets added.
3224  */
3225 static void
3226 nvme_rdma_poll_group_check_disconnected_qpairs(struct spdk_nvme_transport_poll_group *tgroup,
3227 		spdk_nvme_disconnected_qpair_cb disconnected_qpair_cb)
3228 {
3229 }
3230 
3231 static int
3232 nvme_rdma_poll_group_destroy(struct spdk_nvme_transport_poll_group *tgroup)
3233 {
3234 	struct nvme_rdma_poll_group	*group = nvme_rdma_poll_group(tgroup);
3235 
3236 	if (!STAILQ_EMPTY(&tgroup->connected_qpairs) || !STAILQ_EMPTY(&tgroup->disconnected_qpairs)) {
3237 		return -EBUSY;
3238 	}
3239 
3240 	nvme_rdma_poll_group_free_pollers(group);
3241 	free(group);
3242 
3243 	return 0;
3244 }
3245 
3246 static int
3247 nvme_rdma_poll_group_get_stats(struct spdk_nvme_transport_poll_group *tgroup,
3248 			       struct spdk_nvme_transport_poll_group_stat **_stats)
3249 {
3250 	struct nvme_rdma_poll_group *group;
3251 	struct spdk_nvme_transport_poll_group_stat *stats;
3252 	struct spdk_nvme_rdma_device_stat *device_stat;
3253 	struct nvme_rdma_poller *poller;
3254 	uint32_t i = 0;
3255 
3256 	if (tgroup == NULL || _stats == NULL) {
3257 		SPDK_ERRLOG("Invalid stats or group pointer\n");
3258 		return -EINVAL;
3259 	}
3260 
3261 	group = nvme_rdma_poll_group(tgroup);
3262 	stats = calloc(1, sizeof(*stats));
3263 	if (!stats) {
3264 		SPDK_ERRLOG("Can't allocate memory for RDMA stats\n");
3265 		return -ENOMEM;
3266 	}
3267 	stats->trtype = SPDK_NVME_TRANSPORT_RDMA;
3268 	stats->rdma.num_devices = group->num_pollers;
3269 
3270 	if (stats->rdma.num_devices == 0) {
3271 		*_stats = stats;
3272 		return 0;
3273 	}
3274 
3275 	stats->rdma.device_stats = calloc(stats->rdma.num_devices, sizeof(*stats->rdma.device_stats));
3276 	if (!stats->rdma.device_stats) {
3277 		SPDK_ERRLOG("Can't allocate memory for RDMA device stats\n");
3278 		free(stats);
3279 		return -ENOMEM;
3280 	}
3281 
3282 	STAILQ_FOREACH(poller, &group->pollers, link) {
3283 		device_stat = &stats->rdma.device_stats[i];
3284 		device_stat->name = poller->device->device->name;
3285 		device_stat->polls = poller->stats.polls;
3286 		device_stat->idle_polls = poller->stats.idle_polls;
3287 		device_stat->completions = poller->stats.completions;
3288 		device_stat->queued_requests = poller->stats.queued_requests;
3289 		device_stat->total_send_wrs = poller->stats.rdma_stats.send.num_submitted_wrs;
3290 		device_stat->send_doorbell_updates = poller->stats.rdma_stats.send.doorbell_updates;
3291 		device_stat->total_recv_wrs = poller->stats.rdma_stats.recv.num_submitted_wrs;
3292 		device_stat->recv_doorbell_updates = poller->stats.rdma_stats.recv.doorbell_updates;
3293 		i++;
3294 	}
3295 
3296 	*_stats = stats;
3297 
3298 	return 0;
3299 }
3300 
3301 static void
3302 nvme_rdma_poll_group_free_stats(struct spdk_nvme_transport_poll_group *tgroup,
3303 				struct spdk_nvme_transport_poll_group_stat *stats)
3304 {
3305 	if (stats) {
3306 		free(stats->rdma.device_stats);
3307 	}
3308 	free(stats);
3309 }
3310 
3311 static int
3312 nvme_rdma_ctrlr_get_memory_domains(const struct spdk_nvme_ctrlr *ctrlr,
3313 				   struct spdk_memory_domain **domains, int array_size)
3314 {
3315 	struct nvme_rdma_qpair *rqpair = nvme_rdma_qpair(ctrlr->adminq);
3316 
3317 	if (domains && array_size > 0) {
3318 		domains[0] = rqpair->memory_domain;
3319 	}
3320 
3321 	return 1;
3322 }
3323 
3324 void
3325 spdk_nvme_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
3326 {
3327 	g_nvme_hooks = *hooks;
3328 }
3329 
3330 const struct spdk_nvme_transport_ops rdma_ops = {
3331 	.name = "RDMA",
3332 	.type = SPDK_NVME_TRANSPORT_RDMA,
3333 	.ctrlr_construct = nvme_rdma_ctrlr_construct,
3334 	.ctrlr_scan = nvme_fabric_ctrlr_scan,
3335 	.ctrlr_destruct = nvme_rdma_ctrlr_destruct,
3336 	.ctrlr_enable = nvme_rdma_ctrlr_enable,
3337 
3338 	.ctrlr_set_reg_4 = nvme_fabric_ctrlr_set_reg_4,
3339 	.ctrlr_set_reg_8 = nvme_fabric_ctrlr_set_reg_8,
3340 	.ctrlr_get_reg_4 = nvme_fabric_ctrlr_get_reg_4,
3341 	.ctrlr_get_reg_8 = nvme_fabric_ctrlr_get_reg_8,
3342 	.ctrlr_set_reg_4_async = nvme_fabric_ctrlr_set_reg_4_async,
3343 	.ctrlr_set_reg_8_async = nvme_fabric_ctrlr_set_reg_8_async,
3344 	.ctrlr_get_reg_4_async = nvme_fabric_ctrlr_get_reg_4_async,
3345 	.ctrlr_get_reg_8_async = nvme_fabric_ctrlr_get_reg_8_async,
3346 
3347 	.ctrlr_get_max_xfer_size = nvme_rdma_ctrlr_get_max_xfer_size,
3348 	.ctrlr_get_max_sges = nvme_rdma_ctrlr_get_max_sges,
3349 
3350 	.ctrlr_create_io_qpair = nvme_rdma_ctrlr_create_io_qpair,
3351 	.ctrlr_delete_io_qpair = nvme_rdma_ctrlr_delete_io_qpair,
3352 	.ctrlr_connect_qpair = nvme_rdma_ctrlr_connect_qpair,
3353 	.ctrlr_disconnect_qpair = nvme_rdma_ctrlr_disconnect_qpair,
3354 
3355 	.ctrlr_get_memory_domains = nvme_rdma_ctrlr_get_memory_domains,
3356 
3357 	.qpair_abort_reqs = nvme_rdma_qpair_abort_reqs,
3358 	.qpair_reset = nvme_rdma_qpair_reset,
3359 	.qpair_submit_request = nvme_rdma_qpair_submit_request,
3360 	.qpair_process_completions = nvme_rdma_qpair_process_completions,
3361 	.qpair_iterate_requests = nvme_rdma_qpair_iterate_requests,
3362 	.qpair_authenticate = nvme_rdma_qpair_authenticate,
3363 	.admin_qpair_abort_aers = nvme_rdma_admin_qpair_abort_aers,
3364 
3365 	.poll_group_create = nvme_rdma_poll_group_create,
3366 	.poll_group_connect_qpair = nvme_rdma_poll_group_connect_qpair,
3367 	.poll_group_disconnect_qpair = nvme_rdma_poll_group_disconnect_qpair,
3368 	.poll_group_add = nvme_rdma_poll_group_add,
3369 	.poll_group_remove = nvme_rdma_poll_group_remove,
3370 	.poll_group_process_completions = nvme_rdma_poll_group_process_completions,
3371 	.poll_group_check_disconnected_qpairs = nvme_rdma_poll_group_check_disconnected_qpairs,
3372 	.poll_group_destroy = nvme_rdma_poll_group_destroy,
3373 	.poll_group_get_stats = nvme_rdma_poll_group_get_stats,
3374 	.poll_group_free_stats = nvme_rdma_poll_group_free_stats,
3375 };
3376 
3377 SPDK_NVME_TRANSPORT_REGISTER(rdma, &rdma_ops);
3378