xref: /spdk/lib/nvmf/rdma.c (revision 0ecbe09bc18245c46ebf6a3aae64ce64ea26c067)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2019-2021 Mellanox Technologies LTD. All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "spdk/stdinc.h"
35 
36 #include "spdk/config.h"
37 #include "spdk/thread.h"
38 #include "spdk/likely.h"
39 #include "spdk/nvmf_transport.h"
40 #include "spdk/string.h"
41 #include "spdk/trace.h"
42 #include "spdk/util.h"
43 
44 #include "spdk_internal/assert.h"
45 #include "spdk/log.h"
46 #include "spdk_internal/rdma.h"
47 
48 #include "nvmf_internal.h"
49 
50 #include "spdk_internal/trace_defs.h"
51 
52 struct spdk_nvme_rdma_hooks g_nvmf_hooks = {};
53 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma;
54 
55 /*
56  RDMA Connection Resource Defaults
57  */
58 #define NVMF_DEFAULT_TX_SGE		SPDK_NVMF_MAX_SGL_ENTRIES
59 #define NVMF_DEFAULT_RSP_SGE		1
60 #define NVMF_DEFAULT_RX_SGE		2
61 
62 /* The RDMA completion queue size */
63 #define DEFAULT_NVMF_RDMA_CQ_SIZE	4096
64 #define MAX_WR_PER_QP(queue_depth)	(queue_depth * 3 + 2)
65 
66 /* rxe driver vendor_id has been changed from 0 to 0XFFFFFF in 0184afd15a141d7ce24c32c0d86a1e3ba6bc0eb3 */
67 #define NVMF_RXE_VENDOR_ID_OLD 0
68 #define NVMF_RXE_VENDOR_ID_NEW 0XFFFFFF
69 
70 static int g_spdk_nvmf_ibv_query_mask =
71 	IBV_QP_STATE |
72 	IBV_QP_PKEY_INDEX |
73 	IBV_QP_PORT |
74 	IBV_QP_ACCESS_FLAGS |
75 	IBV_QP_AV |
76 	IBV_QP_PATH_MTU |
77 	IBV_QP_DEST_QPN |
78 	IBV_QP_RQ_PSN |
79 	IBV_QP_MAX_DEST_RD_ATOMIC |
80 	IBV_QP_MIN_RNR_TIMER |
81 	IBV_QP_SQ_PSN |
82 	IBV_QP_TIMEOUT |
83 	IBV_QP_RETRY_CNT |
84 	IBV_QP_RNR_RETRY |
85 	IBV_QP_MAX_QP_RD_ATOMIC;
86 
87 enum spdk_nvmf_rdma_request_state {
88 	/* The request is not currently in use */
89 	RDMA_REQUEST_STATE_FREE = 0,
90 
91 	/* Initial state when request first received */
92 	RDMA_REQUEST_STATE_NEW,
93 
94 	/* The request is queued until a data buffer is available. */
95 	RDMA_REQUEST_STATE_NEED_BUFFER,
96 
97 	/* The request is waiting on RDMA queue depth availability
98 	 * to transfer data from the host to the controller.
99 	 */
100 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
101 
102 	/* The request is currently transferring data from the host to the controller. */
103 	RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
104 
105 	/* The request is ready to execute at the block device */
106 	RDMA_REQUEST_STATE_READY_TO_EXECUTE,
107 
108 	/* The request is currently executing at the block device */
109 	RDMA_REQUEST_STATE_EXECUTING,
110 
111 	/* The request finished executing at the block device */
112 	RDMA_REQUEST_STATE_EXECUTED,
113 
114 	/* The request is waiting on RDMA queue depth availability
115 	 * to transfer data from the controller to the host.
116 	 */
117 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
118 
119 	/* The request is ready to send a completion */
120 	RDMA_REQUEST_STATE_READY_TO_COMPLETE,
121 
122 	/* The request is currently transferring data from the controller to the host. */
123 	RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
124 
125 	/* The request currently has an outstanding completion without an
126 	 * associated data transfer.
127 	 */
128 	RDMA_REQUEST_STATE_COMPLETING,
129 
130 	/* The request completed and can be marked free. */
131 	RDMA_REQUEST_STATE_COMPLETED,
132 
133 	/* Terminator */
134 	RDMA_REQUEST_NUM_STATES,
135 };
136 
137 SPDK_TRACE_REGISTER_FN(nvmf_trace, "nvmf_rdma", TRACE_GROUP_NVMF_RDMA)
138 {
139 	spdk_trace_register_object(OBJECT_NVMF_RDMA_IO, 'r');
140 	spdk_trace_register_description("RDMA_REQ_NEW", TRACE_RDMA_REQUEST_STATE_NEW,
141 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 1,
142 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
143 	spdk_trace_register_description("RDMA_REQ_NEED_BUFFER", TRACE_RDMA_REQUEST_STATE_NEED_BUFFER,
144 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
145 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
146 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_C2H",
147 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
148 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
149 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
150 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_H2C",
151 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
152 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
153 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
154 	spdk_trace_register_description("RDMA_REQ_TX_H2C",
155 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
156 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
157 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
158 	spdk_trace_register_description("RDMA_REQ_RDY_TO_EXECUTE",
159 					TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE,
160 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
161 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
162 	spdk_trace_register_description("RDMA_REQ_EXECUTING",
163 					TRACE_RDMA_REQUEST_STATE_EXECUTING,
164 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
165 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
166 	spdk_trace_register_description("RDMA_REQ_EXECUTED",
167 					TRACE_RDMA_REQUEST_STATE_EXECUTED,
168 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
169 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
170 	spdk_trace_register_description("RDMA_REQ_RDY_TO_COMPL",
171 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE,
172 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
173 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
174 	spdk_trace_register_description("RDMA_REQ_COMPLETING_C2H",
175 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
176 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
177 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
178 	spdk_trace_register_description("RDMA_REQ_COMPLETING",
179 					TRACE_RDMA_REQUEST_STATE_COMPLETING,
180 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
181 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
182 	spdk_trace_register_description("RDMA_REQ_COMPLETED",
183 					TRACE_RDMA_REQUEST_STATE_COMPLETED,
184 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0,
185 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
186 
187 	spdk_trace_register_description("RDMA_QP_CREATE", TRACE_RDMA_QP_CREATE,
188 					OWNER_NONE, OBJECT_NONE, 0,
189 					SPDK_TRACE_ARG_TYPE_INT, "");
190 	spdk_trace_register_description("RDMA_IBV_ASYNC_EVENT", TRACE_RDMA_IBV_ASYNC_EVENT,
191 					OWNER_NONE, OBJECT_NONE, 0,
192 					SPDK_TRACE_ARG_TYPE_INT, "type");
193 	spdk_trace_register_description("RDMA_CM_ASYNC_EVENT", TRACE_RDMA_CM_ASYNC_EVENT,
194 					OWNER_NONE, OBJECT_NONE, 0,
195 					SPDK_TRACE_ARG_TYPE_INT, "type");
196 	spdk_trace_register_description("RDMA_QP_STATE_CHANGE", TRACE_RDMA_QP_STATE_CHANGE,
197 					OWNER_NONE, OBJECT_NONE, 0,
198 					SPDK_TRACE_ARG_TYPE_PTR, "state");
199 	spdk_trace_register_description("RDMA_QP_DISCONNECT", TRACE_RDMA_QP_DISCONNECT,
200 					OWNER_NONE, OBJECT_NONE, 0,
201 					SPDK_TRACE_ARG_TYPE_INT, "");
202 	spdk_trace_register_description("RDMA_QP_DESTROY", TRACE_RDMA_QP_DESTROY,
203 					OWNER_NONE, OBJECT_NONE, 0,
204 					SPDK_TRACE_ARG_TYPE_INT, "");
205 }
206 
207 enum spdk_nvmf_rdma_wr_type {
208 	RDMA_WR_TYPE_RECV,
209 	RDMA_WR_TYPE_SEND,
210 	RDMA_WR_TYPE_DATA,
211 };
212 
213 struct spdk_nvmf_rdma_wr {
214 	enum spdk_nvmf_rdma_wr_type	type;
215 };
216 
217 /* This structure holds commands as they are received off the wire.
218  * It must be dynamically paired with a full request object
219  * (spdk_nvmf_rdma_request) to service a request. It is separate
220  * from the request because RDMA does not appear to order
221  * completions, so occasionally we'll get a new incoming
222  * command when there aren't any free request objects.
223  */
224 struct spdk_nvmf_rdma_recv {
225 	struct ibv_recv_wr			wr;
226 	struct ibv_sge				sgl[NVMF_DEFAULT_RX_SGE];
227 
228 	struct spdk_nvmf_rdma_qpair		*qpair;
229 
230 	/* In-capsule data buffer */
231 	uint8_t					*buf;
232 
233 	struct spdk_nvmf_rdma_wr		rdma_wr;
234 	uint64_t				receive_tsc;
235 
236 	STAILQ_ENTRY(spdk_nvmf_rdma_recv)	link;
237 };
238 
239 struct spdk_nvmf_rdma_request_data {
240 	struct spdk_nvmf_rdma_wr	rdma_wr;
241 	struct ibv_send_wr		wr;
242 	struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
243 };
244 
245 struct spdk_nvmf_rdma_request {
246 	struct spdk_nvmf_request		req;
247 
248 	enum spdk_nvmf_rdma_request_state	state;
249 
250 	/* Data offset in req.iov */
251 	uint32_t				offset;
252 
253 	struct spdk_nvmf_rdma_recv		*recv;
254 
255 	struct {
256 		struct spdk_nvmf_rdma_wr	rdma_wr;
257 		struct	ibv_send_wr		wr;
258 		struct	ibv_sge			sgl[NVMF_DEFAULT_RSP_SGE];
259 	} rsp;
260 
261 	struct spdk_nvmf_rdma_request_data	data;
262 
263 	uint32_t				iovpos;
264 
265 	uint32_t				num_outstanding_data_wr;
266 	uint64_t				receive_tsc;
267 
268 	STAILQ_ENTRY(spdk_nvmf_rdma_request)	state_link;
269 };
270 
271 struct spdk_nvmf_rdma_resource_opts {
272 	struct spdk_nvmf_rdma_qpair	*qpair;
273 	/* qp points either to an ibv_qp object or an ibv_srq object depending on the value of shared. */
274 	void				*qp;
275 	struct ibv_pd			*pd;
276 	uint32_t			max_queue_depth;
277 	uint32_t			in_capsule_data_size;
278 	bool				shared;
279 };
280 
281 struct spdk_nvmf_rdma_resources {
282 	/* Array of size "max_queue_depth" containing RDMA requests. */
283 	struct spdk_nvmf_rdma_request		*reqs;
284 
285 	/* Array of size "max_queue_depth" containing RDMA recvs. */
286 	struct spdk_nvmf_rdma_recv		*recvs;
287 
288 	/* Array of size "max_queue_depth" containing 64 byte capsules
289 	 * used for receive.
290 	 */
291 	union nvmf_h2c_msg			*cmds;
292 	struct ibv_mr				*cmds_mr;
293 
294 	/* Array of size "max_queue_depth" containing 16 byte completions
295 	 * to be sent back to the user.
296 	 */
297 	union nvmf_c2h_msg			*cpls;
298 	struct ibv_mr				*cpls_mr;
299 
300 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
301 	 * buffers to be used for in capsule data.
302 	 */
303 	void					*bufs;
304 	struct ibv_mr				*bufs_mr;
305 
306 	/* Receives that are waiting for a request object */
307 	STAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
308 
309 	/* Queue to track free requests */
310 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	free_queue;
311 };
312 
313 typedef void (*spdk_nvmf_rdma_qpair_ibv_event)(struct spdk_nvmf_rdma_qpair *rqpair);
314 
315 struct spdk_nvmf_rdma_ibv_event_ctx {
316 	struct spdk_nvmf_rdma_qpair			*rqpair;
317 	spdk_nvmf_rdma_qpair_ibv_event			cb_fn;
318 	/* Link to other ibv events associated with this qpair */
319 	STAILQ_ENTRY(spdk_nvmf_rdma_ibv_event_ctx)	link;
320 };
321 
322 struct spdk_nvmf_rdma_qpair {
323 	struct spdk_nvmf_qpair			qpair;
324 
325 	struct spdk_nvmf_rdma_device		*device;
326 	struct spdk_nvmf_rdma_poller		*poller;
327 
328 	struct spdk_rdma_qp			*rdma_qp;
329 	struct rdma_cm_id			*cm_id;
330 	struct spdk_rdma_srq			*srq;
331 	struct rdma_cm_id			*listen_id;
332 
333 	/* The maximum number of I/O outstanding on this connection at one time */
334 	uint16_t				max_queue_depth;
335 
336 	/* The maximum number of active RDMA READ and ATOMIC operations at one time */
337 	uint16_t				max_read_depth;
338 
339 	/* The maximum number of RDMA SEND operations at one time */
340 	uint32_t				max_send_depth;
341 
342 	/* The current number of outstanding WRs from this qpair's
343 	 * recv queue. Should not exceed device->attr.max_queue_depth.
344 	 */
345 	uint16_t				current_recv_depth;
346 
347 	/* The current number of active RDMA READ operations */
348 	uint16_t				current_read_depth;
349 
350 	/* The current number of posted WRs from this qpair's
351 	 * send queue. Should not exceed max_send_depth.
352 	 */
353 	uint32_t				current_send_depth;
354 
355 	/* The maximum number of SGEs per WR on the send queue */
356 	uint32_t				max_send_sge;
357 
358 	/* The maximum number of SGEs per WR on the recv queue */
359 	uint32_t				max_recv_sge;
360 
361 	struct spdk_nvmf_rdma_resources		*resources;
362 
363 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_read_queue;
364 
365 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_write_queue;
366 
367 	/* Number of requests not in the free state */
368 	uint32_t				qd;
369 
370 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	link;
371 
372 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	recv_link;
373 
374 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	send_link;
375 
376 	/* IBV queue pair attributes: they are used to manage
377 	 * qp state and recover from errors.
378 	 */
379 	enum ibv_qp_state			ibv_state;
380 
381 	/*
382 	 * io_channel which is used to destroy qpair when it is removed from poll group
383 	 */
384 	struct spdk_io_channel		*destruct_channel;
385 
386 	/* List of ibv async events */
387 	STAILQ_HEAD(, spdk_nvmf_rdma_ibv_event_ctx)	ibv_events;
388 
389 	/* Lets us know that we have received the last_wqe event. */
390 	bool					last_wqe_reached;
391 
392 	/* Indicate that nvmf_rdma_close_qpair is called */
393 	bool					to_close;
394 };
395 
396 struct spdk_nvmf_rdma_poller_stat {
397 	uint64_t				completions;
398 	uint64_t				polls;
399 	uint64_t				idle_polls;
400 	uint64_t				requests;
401 	uint64_t				request_latency;
402 	uint64_t				pending_free_request;
403 	uint64_t				pending_rdma_read;
404 	uint64_t				pending_rdma_write;
405 	struct spdk_rdma_qp_stats		qp_stats;
406 };
407 
408 struct spdk_nvmf_rdma_poller {
409 	struct spdk_nvmf_rdma_device		*device;
410 	struct spdk_nvmf_rdma_poll_group	*group;
411 
412 	int					num_cqe;
413 	int					required_num_wr;
414 	struct ibv_cq				*cq;
415 
416 	/* The maximum number of I/O outstanding on the shared receive queue at one time */
417 	uint16_t				max_srq_depth;
418 
419 	/* Shared receive queue */
420 	struct spdk_rdma_srq			*srq;
421 
422 	struct spdk_nvmf_rdma_resources		*resources;
423 	struct spdk_nvmf_rdma_poller_stat	stat;
424 
425 	TAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs;
426 
427 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_recv;
428 
429 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_send;
430 
431 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
432 };
433 
434 struct spdk_nvmf_rdma_poll_group_stat {
435 	uint64_t				pending_data_buffer;
436 };
437 
438 struct spdk_nvmf_rdma_poll_group {
439 	struct spdk_nvmf_transport_poll_group		group;
440 	struct spdk_nvmf_rdma_poll_group_stat		stat;
441 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)		pollers;
442 	TAILQ_ENTRY(spdk_nvmf_rdma_poll_group)		link;
443 };
444 
445 struct spdk_nvmf_rdma_conn_sched {
446 	struct spdk_nvmf_rdma_poll_group *next_admin_pg;
447 	struct spdk_nvmf_rdma_poll_group *next_io_pg;
448 };
449 
450 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
451 struct spdk_nvmf_rdma_device {
452 	struct ibv_device_attr			attr;
453 	struct ibv_context			*context;
454 
455 	struct spdk_rdma_mem_map		*map;
456 	struct ibv_pd				*pd;
457 
458 	int					num_srq;
459 
460 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
461 };
462 
463 struct spdk_nvmf_rdma_port {
464 	const struct spdk_nvme_transport_id	*trid;
465 	struct rdma_cm_id			*id;
466 	struct spdk_nvmf_rdma_device		*device;
467 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
468 };
469 
470 struct rdma_transport_opts {
471 	int		num_cqe;
472 	uint32_t	max_srq_depth;
473 	bool		no_srq;
474 	bool		no_wr_batching;
475 	int		acceptor_backlog;
476 };
477 
478 struct spdk_nvmf_rdma_transport {
479 	struct spdk_nvmf_transport	transport;
480 	struct rdma_transport_opts	rdma_opts;
481 
482 	struct spdk_nvmf_rdma_conn_sched conn_sched;
483 
484 	struct rdma_event_channel	*event_channel;
485 
486 	struct spdk_mempool		*data_wr_pool;
487 
488 	pthread_mutex_t			lock;
489 
490 	/* fields used to poll RDMA/IB events */
491 	nfds_t			npoll_fds;
492 	struct pollfd		*poll_fds;
493 
494 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
495 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
496 	TAILQ_HEAD(, spdk_nvmf_rdma_poll_group)	poll_groups;
497 };
498 
499 static const struct spdk_json_object_decoder rdma_transport_opts_decoder[] = {
500 	{
501 		"num_cqe", offsetof(struct rdma_transport_opts, num_cqe),
502 		spdk_json_decode_int32, true
503 	},
504 	{
505 		"max_srq_depth", offsetof(struct rdma_transport_opts, max_srq_depth),
506 		spdk_json_decode_uint32, true
507 	},
508 	{
509 		"no_srq", offsetof(struct rdma_transport_opts, no_srq),
510 		spdk_json_decode_bool, true
511 	},
512 	{
513 		"no_wr_batching", offsetof(struct rdma_transport_opts, no_wr_batching),
514 		spdk_json_decode_bool, true
515 	},
516 	{
517 		"acceptor_backlog", offsetof(struct rdma_transport_opts, acceptor_backlog),
518 		spdk_json_decode_int32, true
519 	},
520 };
521 
522 static bool
523 nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
524 			  struct spdk_nvmf_rdma_request *rdma_req);
525 
526 static void
527 _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
528 		     struct spdk_nvmf_rdma_poller *rpoller);
529 
530 static void
531 _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
532 		     struct spdk_nvmf_rdma_poller *rpoller);
533 
534 static inline int
535 nvmf_rdma_check_ibv_state(enum ibv_qp_state state)
536 {
537 	switch (state) {
538 	case IBV_QPS_RESET:
539 	case IBV_QPS_INIT:
540 	case IBV_QPS_RTR:
541 	case IBV_QPS_RTS:
542 	case IBV_QPS_SQD:
543 	case IBV_QPS_SQE:
544 	case IBV_QPS_ERR:
545 		return 0;
546 	default:
547 		return -1;
548 	}
549 }
550 
551 static inline enum spdk_nvme_media_error_status_code
552 nvmf_rdma_dif_error_to_compl_status(uint8_t err_type) {
553 	enum spdk_nvme_media_error_status_code result;
554 	switch (err_type)
555 	{
556 	case SPDK_DIF_REFTAG_ERROR:
557 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
558 		break;
559 	case SPDK_DIF_APPTAG_ERROR:
560 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
561 		break;
562 	case SPDK_DIF_GUARD_ERROR:
563 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
564 		break;
565 	default:
566 		SPDK_UNREACHABLE();
567 	}
568 
569 	return result;
570 }
571 
572 static enum ibv_qp_state
573 nvmf_rdma_update_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair) {
574 	enum ibv_qp_state old_state, new_state;
575 	struct ibv_qp_attr qp_attr;
576 	struct ibv_qp_init_attr init_attr;
577 	int rc;
578 
579 	old_state = rqpair->ibv_state;
580 	rc = ibv_query_qp(rqpair->rdma_qp->qp, &qp_attr,
581 			  g_spdk_nvmf_ibv_query_mask, &init_attr);
582 
583 	if (rc)
584 	{
585 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
586 		return IBV_QPS_ERR + 1;
587 	}
588 
589 	new_state = qp_attr.qp_state;
590 	rqpair->ibv_state = new_state;
591 	qp_attr.ah_attr.port_num = qp_attr.port_num;
592 
593 	rc = nvmf_rdma_check_ibv_state(new_state);
594 	if (rc)
595 	{
596 		SPDK_ERRLOG("QP#%d: bad state updated: %u, maybe hardware issue\n", rqpair->qpair.qid, new_state);
597 		/*
598 		 * IBV_QPS_UNKNOWN undefined if lib version smaller than libibverbs-1.1.8
599 		 * IBV_QPS_UNKNOWN is the enum element after IBV_QPS_ERR
600 		 */
601 		return IBV_QPS_ERR + 1;
602 	}
603 
604 	if (old_state != new_state)
605 	{
606 		spdk_trace_record(TRACE_RDMA_QP_STATE_CHANGE, 0, 0, (uintptr_t)rqpair, new_state);
607 	}
608 	return new_state;
609 }
610 
611 static void
612 nvmf_rdma_request_free_data(struct spdk_nvmf_rdma_request *rdma_req,
613 			    struct spdk_nvmf_rdma_transport *rtransport)
614 {
615 	struct spdk_nvmf_rdma_request_data	*data_wr;
616 	struct ibv_send_wr			*next_send_wr;
617 	uint64_t				req_wrid;
618 
619 	rdma_req->num_outstanding_data_wr = 0;
620 	data_wr = &rdma_req->data;
621 	req_wrid = data_wr->wr.wr_id;
622 	while (data_wr && data_wr->wr.wr_id == req_wrid) {
623 		memset(data_wr->sgl, 0, sizeof(data_wr->wr.sg_list[0]) * data_wr->wr.num_sge);
624 		data_wr->wr.num_sge = 0;
625 		next_send_wr = data_wr->wr.next;
626 		if (data_wr != &rdma_req->data) {
627 			spdk_mempool_put(rtransport->data_wr_pool, data_wr);
628 		}
629 		data_wr = (!next_send_wr || next_send_wr == &rdma_req->rsp.wr) ? NULL :
630 			  SPDK_CONTAINEROF(next_send_wr, struct spdk_nvmf_rdma_request_data, wr);
631 	}
632 }
633 
634 static void
635 nvmf_rdma_dump_request(struct spdk_nvmf_rdma_request *req)
636 {
637 	SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", req->req.data_from_pool);
638 	if (req->req.cmd) {
639 		SPDK_ERRLOG("\t\tRequest opcode: %d\n", req->req.cmd->nvmf_cmd.opcode);
640 	}
641 	if (req->recv) {
642 		SPDK_ERRLOG("\t\tRequest recv wr_id%lu\n", req->recv->wr.wr_id);
643 	}
644 }
645 
646 static void
647 nvmf_rdma_dump_qpair_contents(struct spdk_nvmf_rdma_qpair *rqpair)
648 {
649 	int i;
650 
651 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", rqpair->qpair.qid);
652 	for (i = 0; i < rqpair->max_queue_depth; i++) {
653 		if (rqpair->resources->reqs[i].state != RDMA_REQUEST_STATE_FREE) {
654 			nvmf_rdma_dump_request(&rqpair->resources->reqs[i]);
655 		}
656 	}
657 }
658 
659 static void
660 nvmf_rdma_resources_destroy(struct spdk_nvmf_rdma_resources *resources)
661 {
662 	if (resources->cmds_mr) {
663 		ibv_dereg_mr(resources->cmds_mr);
664 	}
665 
666 	if (resources->cpls_mr) {
667 		ibv_dereg_mr(resources->cpls_mr);
668 	}
669 
670 	if (resources->bufs_mr) {
671 		ibv_dereg_mr(resources->bufs_mr);
672 	}
673 
674 	spdk_free(resources->cmds);
675 	spdk_free(resources->cpls);
676 	spdk_free(resources->bufs);
677 	free(resources->reqs);
678 	free(resources->recvs);
679 	free(resources);
680 }
681 
682 
683 static struct spdk_nvmf_rdma_resources *
684 nvmf_rdma_resources_create(struct spdk_nvmf_rdma_resource_opts *opts)
685 {
686 	struct spdk_nvmf_rdma_resources	*resources;
687 	struct spdk_nvmf_rdma_request	*rdma_req;
688 	struct spdk_nvmf_rdma_recv	*rdma_recv;
689 	struct spdk_rdma_qp		*qp = NULL;
690 	struct spdk_rdma_srq		*srq = NULL;
691 	struct ibv_recv_wr		*bad_wr = NULL;
692 	uint32_t			i;
693 	int				rc = 0;
694 
695 	resources = calloc(1, sizeof(struct spdk_nvmf_rdma_resources));
696 	if (!resources) {
697 		SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
698 		return NULL;
699 	}
700 
701 	resources->reqs = calloc(opts->max_queue_depth, sizeof(*resources->reqs));
702 	resources->recvs = calloc(opts->max_queue_depth, sizeof(*resources->recvs));
703 	resources->cmds = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cmds),
704 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
705 	resources->cpls = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cpls),
706 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
707 
708 	if (opts->in_capsule_data_size > 0) {
709 		resources->bufs = spdk_zmalloc(opts->max_queue_depth * opts->in_capsule_data_size,
710 					       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY,
711 					       SPDK_MALLOC_DMA);
712 	}
713 
714 	if (!resources->reqs || !resources->recvs || !resources->cmds ||
715 	    !resources->cpls || (opts->in_capsule_data_size && !resources->bufs)) {
716 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
717 		goto cleanup;
718 	}
719 
720 	resources->cmds_mr = ibv_reg_mr(opts->pd, resources->cmds,
721 					opts->max_queue_depth * sizeof(*resources->cmds),
722 					IBV_ACCESS_LOCAL_WRITE);
723 	resources->cpls_mr = ibv_reg_mr(opts->pd, resources->cpls,
724 					opts->max_queue_depth * sizeof(*resources->cpls),
725 					0);
726 
727 	if (opts->in_capsule_data_size) {
728 		resources->bufs_mr = ibv_reg_mr(opts->pd, resources->bufs,
729 						opts->max_queue_depth *
730 						opts->in_capsule_data_size,
731 						IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
732 	}
733 
734 	if (!resources->cmds_mr || !resources->cpls_mr ||
735 	    (opts->in_capsule_data_size &&
736 	     !resources->bufs_mr)) {
737 		goto cleanup;
738 	}
739 	SPDK_DEBUGLOG(rdma, "Command Array: %p Length: %lx LKey: %x\n",
740 		      resources->cmds, opts->max_queue_depth * sizeof(*resources->cmds),
741 		      resources->cmds_mr->lkey);
742 	SPDK_DEBUGLOG(rdma, "Completion Array: %p Length: %lx LKey: %x\n",
743 		      resources->cpls, opts->max_queue_depth * sizeof(*resources->cpls),
744 		      resources->cpls_mr->lkey);
745 	if (resources->bufs && resources->bufs_mr) {
746 		SPDK_DEBUGLOG(rdma, "In Capsule Data Array: %p Length: %x LKey: %x\n",
747 			      resources->bufs, opts->max_queue_depth *
748 			      opts->in_capsule_data_size, resources->bufs_mr->lkey);
749 	}
750 
751 	/* Initialize queues */
752 	STAILQ_INIT(&resources->incoming_queue);
753 	STAILQ_INIT(&resources->free_queue);
754 
755 	if (opts->shared) {
756 		srq = (struct spdk_rdma_srq *)opts->qp;
757 	} else {
758 		qp = (struct spdk_rdma_qp *)opts->qp;
759 	}
760 
761 	for (i = 0; i < opts->max_queue_depth; i++) {
762 		rdma_recv = &resources->recvs[i];
763 		rdma_recv->qpair = opts->qpair;
764 
765 		/* Set up memory to receive commands */
766 		if (resources->bufs) {
767 			rdma_recv->buf = (void *)((uintptr_t)resources->bufs + (i *
768 						  opts->in_capsule_data_size));
769 		}
770 
771 		rdma_recv->rdma_wr.type = RDMA_WR_TYPE_RECV;
772 
773 		rdma_recv->sgl[0].addr = (uintptr_t)&resources->cmds[i];
774 		rdma_recv->sgl[0].length = sizeof(resources->cmds[i]);
775 		rdma_recv->sgl[0].lkey = resources->cmds_mr->lkey;
776 		rdma_recv->wr.num_sge = 1;
777 
778 		if (rdma_recv->buf && resources->bufs_mr) {
779 			rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
780 			rdma_recv->sgl[1].length = opts->in_capsule_data_size;
781 			rdma_recv->sgl[1].lkey = resources->bufs_mr->lkey;
782 			rdma_recv->wr.num_sge++;
783 		}
784 
785 		rdma_recv->wr.wr_id = (uintptr_t)&rdma_recv->rdma_wr;
786 		rdma_recv->wr.sg_list = rdma_recv->sgl;
787 		if (srq) {
788 			spdk_rdma_srq_queue_recv_wrs(srq, &rdma_recv->wr);
789 		} else {
790 			spdk_rdma_qp_queue_recv_wrs(qp, &rdma_recv->wr);
791 		}
792 	}
793 
794 	for (i = 0; i < opts->max_queue_depth; i++) {
795 		rdma_req = &resources->reqs[i];
796 
797 		if (opts->qpair != NULL) {
798 			rdma_req->req.qpair = &opts->qpair->qpair;
799 		} else {
800 			rdma_req->req.qpair = NULL;
801 		}
802 		rdma_req->req.cmd = NULL;
803 
804 		/* Set up memory to send responses */
805 		rdma_req->req.rsp = &resources->cpls[i];
806 
807 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&resources->cpls[i];
808 		rdma_req->rsp.sgl[0].length = sizeof(resources->cpls[i]);
809 		rdma_req->rsp.sgl[0].lkey = resources->cpls_mr->lkey;
810 
811 		rdma_req->rsp.rdma_wr.type = RDMA_WR_TYPE_SEND;
812 		rdma_req->rsp.wr.wr_id = (uintptr_t)&rdma_req->rsp.rdma_wr;
813 		rdma_req->rsp.wr.next = NULL;
814 		rdma_req->rsp.wr.opcode = IBV_WR_SEND;
815 		rdma_req->rsp.wr.send_flags = IBV_SEND_SIGNALED;
816 		rdma_req->rsp.wr.sg_list = rdma_req->rsp.sgl;
817 		rdma_req->rsp.wr.num_sge = SPDK_COUNTOF(rdma_req->rsp.sgl);
818 
819 		/* Set up memory for data buffers */
820 		rdma_req->data.rdma_wr.type = RDMA_WR_TYPE_DATA;
821 		rdma_req->data.wr.wr_id = (uintptr_t)&rdma_req->data.rdma_wr;
822 		rdma_req->data.wr.next = NULL;
823 		rdma_req->data.wr.send_flags = IBV_SEND_SIGNALED;
824 		rdma_req->data.wr.sg_list = rdma_req->data.sgl;
825 		rdma_req->data.wr.num_sge = SPDK_COUNTOF(rdma_req->data.sgl);
826 
827 		/* Initialize request state to FREE */
828 		rdma_req->state = RDMA_REQUEST_STATE_FREE;
829 		STAILQ_INSERT_TAIL(&resources->free_queue, rdma_req, state_link);
830 	}
831 
832 	if (srq) {
833 		rc = spdk_rdma_srq_flush_recv_wrs(srq, &bad_wr);
834 	} else {
835 		rc = spdk_rdma_qp_flush_recv_wrs(qp, &bad_wr);
836 	}
837 
838 	if (rc) {
839 		goto cleanup;
840 	}
841 
842 	return resources;
843 
844 cleanup:
845 	nvmf_rdma_resources_destroy(resources);
846 	return NULL;
847 }
848 
849 static void
850 nvmf_rdma_qpair_clean_ibv_events(struct spdk_nvmf_rdma_qpair *rqpair)
851 {
852 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx, *tctx;
853 	STAILQ_FOREACH_SAFE(ctx, &rqpair->ibv_events, link, tctx) {
854 		ctx->rqpair = NULL;
855 		/* Memory allocated for ctx is freed in nvmf_rdma_qpair_process_ibv_event */
856 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
857 	}
858 }
859 
860 static void
861 nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
862 {
863 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
864 	struct ibv_recv_wr		*bad_recv_wr = NULL;
865 	int				rc;
866 
867 	spdk_trace_record(TRACE_RDMA_QP_DESTROY, 0, 0, (uintptr_t)rqpair);
868 
869 	if (rqpair->qd != 0) {
870 		struct spdk_nvmf_qpair *qpair = &rqpair->qpair;
871 		struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(qpair->transport,
872 				struct spdk_nvmf_rdma_transport, transport);
873 		struct spdk_nvmf_rdma_request *req;
874 		uint32_t i, max_req_count = 0;
875 
876 		SPDK_WARNLOG("Destroying qpair when queue depth is %d\n", rqpair->qd);
877 
878 		if (rqpair->srq == NULL) {
879 			nvmf_rdma_dump_qpair_contents(rqpair);
880 			max_req_count = rqpair->max_queue_depth;
881 		} else if (rqpair->poller && rqpair->resources) {
882 			max_req_count = rqpair->poller->max_srq_depth;
883 		}
884 
885 		SPDK_DEBUGLOG(rdma, "Release incomplete requests\n");
886 		for (i = 0; i < max_req_count; i++) {
887 			req = &rqpair->resources->reqs[i];
888 			if (req->req.qpair == qpair && req->state != RDMA_REQUEST_STATE_FREE) {
889 				/* nvmf_rdma_request_process checks qpair ibv and internal state
890 				 * and completes a request */
891 				nvmf_rdma_request_process(rtransport, req);
892 			}
893 		}
894 		assert(rqpair->qd == 0);
895 	}
896 
897 	if (rqpair->poller) {
898 		TAILQ_REMOVE(&rqpair->poller->qpairs, rqpair, link);
899 
900 		if (rqpair->srq != NULL && rqpair->resources != NULL) {
901 			/* Drop all received but unprocessed commands for this queue and return them to SRQ */
902 			STAILQ_FOREACH_SAFE(rdma_recv, &rqpair->resources->incoming_queue, link, recv_tmp) {
903 				if (rqpair == rdma_recv->qpair) {
904 					STAILQ_REMOVE(&rqpair->resources->incoming_queue, rdma_recv, spdk_nvmf_rdma_recv, link);
905 					spdk_rdma_srq_queue_recv_wrs(rqpair->srq, &rdma_recv->wr);
906 					rc = spdk_rdma_srq_flush_recv_wrs(rqpair->srq, &bad_recv_wr);
907 					if (rc) {
908 						SPDK_ERRLOG("Unable to re-post rx descriptor\n");
909 					}
910 				}
911 			}
912 		}
913 	}
914 
915 	if (rqpair->cm_id) {
916 		if (rqpair->rdma_qp != NULL) {
917 			spdk_rdma_qp_destroy(rqpair->rdma_qp);
918 			rqpair->rdma_qp = NULL;
919 		}
920 		rdma_destroy_id(rqpair->cm_id);
921 
922 		if (rqpair->poller != NULL && rqpair->srq == NULL) {
923 			rqpair->poller->required_num_wr -= MAX_WR_PER_QP(rqpair->max_queue_depth);
924 		}
925 	}
926 
927 	if (rqpair->srq == NULL && rqpair->resources != NULL) {
928 		nvmf_rdma_resources_destroy(rqpair->resources);
929 	}
930 
931 	nvmf_rdma_qpair_clean_ibv_events(rqpair);
932 
933 	if (rqpair->destruct_channel) {
934 		spdk_put_io_channel(rqpair->destruct_channel);
935 		rqpair->destruct_channel = NULL;
936 	}
937 
938 	free(rqpair);
939 }
940 
941 static int
942 nvmf_rdma_resize_cq(struct spdk_nvmf_rdma_qpair *rqpair, struct spdk_nvmf_rdma_device *device)
943 {
944 	struct spdk_nvmf_rdma_poller	*rpoller;
945 	int				rc, num_cqe, required_num_wr;
946 
947 	/* Enlarge CQ size dynamically */
948 	rpoller = rqpair->poller;
949 	required_num_wr = rpoller->required_num_wr + MAX_WR_PER_QP(rqpair->max_queue_depth);
950 	num_cqe = rpoller->num_cqe;
951 	if (num_cqe < required_num_wr) {
952 		num_cqe = spdk_max(num_cqe * 2, required_num_wr);
953 		num_cqe = spdk_min(num_cqe, device->attr.max_cqe);
954 	}
955 
956 	if (rpoller->num_cqe != num_cqe) {
957 		if (device->context->device->transport_type == IBV_TRANSPORT_IWARP) {
958 			SPDK_ERRLOG("iWARP doesn't support CQ resize. Current capacity %u, required %u\n"
959 				    "Using CQ of insufficient size may lead to CQ overrun\n", rpoller->num_cqe, num_cqe);
960 			return -1;
961 		}
962 		if (required_num_wr > device->attr.max_cqe) {
963 			SPDK_ERRLOG("RDMA CQE requirement (%d) exceeds device max_cqe limitation (%d)\n",
964 				    required_num_wr, device->attr.max_cqe);
965 			return -1;
966 		}
967 
968 		SPDK_DEBUGLOG(rdma, "Resize RDMA CQ from %d to %d\n", rpoller->num_cqe, num_cqe);
969 		rc = ibv_resize_cq(rpoller->cq, num_cqe);
970 		if (rc) {
971 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
972 			return -1;
973 		}
974 
975 		rpoller->num_cqe = num_cqe;
976 	}
977 
978 	rpoller->required_num_wr = required_num_wr;
979 	return 0;
980 }
981 
982 static int
983 nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
984 {
985 	struct spdk_nvmf_rdma_qpair		*rqpair;
986 	struct spdk_nvmf_rdma_transport		*rtransport;
987 	struct spdk_nvmf_transport		*transport;
988 	struct spdk_nvmf_rdma_resource_opts	opts;
989 	struct spdk_nvmf_rdma_device		*device;
990 	struct spdk_rdma_qp_init_attr		qp_init_attr = {};
991 
992 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
993 	device = rqpair->device;
994 
995 	qp_init_attr.qp_context	= rqpair;
996 	qp_init_attr.pd		= device->pd;
997 	qp_init_attr.send_cq	= rqpair->poller->cq;
998 	qp_init_attr.recv_cq	= rqpair->poller->cq;
999 
1000 	if (rqpair->srq) {
1001 		qp_init_attr.srq		= rqpair->srq->srq;
1002 	} else {
1003 		qp_init_attr.cap.max_recv_wr	= rqpair->max_queue_depth;
1004 	}
1005 
1006 	/* SEND, READ, and WRITE operations */
1007 	qp_init_attr.cap.max_send_wr	= (uint32_t)rqpair->max_queue_depth * 2;
1008 	qp_init_attr.cap.max_send_sge	= spdk_min((uint32_t)device->attr.max_sge, NVMF_DEFAULT_TX_SGE);
1009 	qp_init_attr.cap.max_recv_sge	= spdk_min((uint32_t)device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
1010 	qp_init_attr.stats		= &rqpair->poller->stat.qp_stats;
1011 
1012 	if (rqpair->srq == NULL && nvmf_rdma_resize_cq(rqpair, device) < 0) {
1013 		SPDK_ERRLOG("Failed to resize the completion queue. Cannot initialize qpair.\n");
1014 		goto error;
1015 	}
1016 
1017 	rqpair->rdma_qp = spdk_rdma_qp_create(rqpair->cm_id, &qp_init_attr);
1018 	if (!rqpair->rdma_qp) {
1019 		goto error;
1020 	}
1021 
1022 	rqpair->max_send_depth = spdk_min((uint32_t)(rqpair->max_queue_depth * 2),
1023 					  qp_init_attr.cap.max_send_wr);
1024 	rqpair->max_send_sge = spdk_min(NVMF_DEFAULT_TX_SGE, qp_init_attr.cap.max_send_sge);
1025 	rqpair->max_recv_sge = spdk_min(NVMF_DEFAULT_RX_SGE, qp_init_attr.cap.max_recv_sge);
1026 	spdk_trace_record(TRACE_RDMA_QP_CREATE, 0, 0, (uintptr_t)rqpair);
1027 	SPDK_DEBUGLOG(rdma, "New RDMA Connection: %p\n", qpair);
1028 
1029 	if (rqpair->poller->srq == NULL) {
1030 		rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
1031 		transport = &rtransport->transport;
1032 
1033 		opts.qp = rqpair->rdma_qp;
1034 		opts.pd = rqpair->cm_id->pd;
1035 		opts.qpair = rqpair;
1036 		opts.shared = false;
1037 		opts.max_queue_depth = rqpair->max_queue_depth;
1038 		opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
1039 
1040 		rqpair->resources = nvmf_rdma_resources_create(&opts);
1041 
1042 		if (!rqpair->resources) {
1043 			SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
1044 			rdma_destroy_qp(rqpair->cm_id);
1045 			goto error;
1046 		}
1047 	} else {
1048 		rqpair->resources = rqpair->poller->resources;
1049 	}
1050 
1051 	rqpair->current_recv_depth = 0;
1052 	STAILQ_INIT(&rqpair->pending_rdma_read_queue);
1053 	STAILQ_INIT(&rqpair->pending_rdma_write_queue);
1054 
1055 	return 0;
1056 
1057 error:
1058 	rdma_destroy_id(rqpair->cm_id);
1059 	rqpair->cm_id = NULL;
1060 	return -1;
1061 }
1062 
1063 /* Append the given recv wr structure to the resource structs outstanding recvs list. */
1064 /* This function accepts either a single wr or the first wr in a linked list. */
1065 static void
1066 nvmf_rdma_qpair_queue_recv_wrs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *first)
1067 {
1068 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
1069 			struct spdk_nvmf_rdma_transport, transport);
1070 
1071 	if (rqpair->srq != NULL) {
1072 		spdk_rdma_srq_queue_recv_wrs(rqpair->srq, first);
1073 	} else {
1074 		if (spdk_rdma_qp_queue_recv_wrs(rqpair->rdma_qp, first)) {
1075 			STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_recv, rqpair, recv_link);
1076 		}
1077 	}
1078 
1079 	if (rtransport->rdma_opts.no_wr_batching) {
1080 		_poller_submit_recvs(rtransport, rqpair->poller);
1081 	}
1082 }
1083 
1084 static int
1085 request_transfer_in(struct spdk_nvmf_request *req)
1086 {
1087 	struct spdk_nvmf_rdma_request	*rdma_req;
1088 	struct spdk_nvmf_qpair		*qpair;
1089 	struct spdk_nvmf_rdma_qpair	*rqpair;
1090 	struct spdk_nvmf_rdma_transport *rtransport;
1091 
1092 	qpair = req->qpair;
1093 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1094 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1095 	rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
1096 				      struct spdk_nvmf_rdma_transport, transport);
1097 
1098 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
1099 	assert(rdma_req != NULL);
1100 
1101 	if (spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, &rdma_req->data.wr)) {
1102 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1103 	}
1104 	if (rtransport->rdma_opts.no_wr_batching) {
1105 		_poller_submit_sends(rtransport, rqpair->poller);
1106 	}
1107 
1108 	rqpair->current_read_depth += rdma_req->num_outstanding_data_wr;
1109 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr;
1110 	return 0;
1111 }
1112 
1113 static int
1114 request_transfer_out(struct spdk_nvmf_request *req, int *data_posted)
1115 {
1116 	int				num_outstanding_data_wr = 0;
1117 	struct spdk_nvmf_rdma_request	*rdma_req;
1118 	struct spdk_nvmf_qpair		*qpair;
1119 	struct spdk_nvmf_rdma_qpair	*rqpair;
1120 	struct spdk_nvme_cpl		*rsp;
1121 	struct ibv_send_wr		*first = NULL;
1122 	struct spdk_nvmf_rdma_transport *rtransport;
1123 
1124 	*data_posted = 0;
1125 	qpair = req->qpair;
1126 	rsp = &req->rsp->nvme_cpl;
1127 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1128 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1129 	rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
1130 				      struct spdk_nvmf_rdma_transport, transport);
1131 
1132 	/* Advance our sq_head pointer */
1133 	if (qpair->sq_head == qpair->sq_head_max) {
1134 		qpair->sq_head = 0;
1135 	} else {
1136 		qpair->sq_head++;
1137 	}
1138 	rsp->sqhd = qpair->sq_head;
1139 
1140 	/* queue the capsule for the recv buffer */
1141 	assert(rdma_req->recv != NULL);
1142 
1143 	nvmf_rdma_qpair_queue_recv_wrs(rqpair, &rdma_req->recv->wr);
1144 
1145 	rdma_req->recv = NULL;
1146 	assert(rqpair->current_recv_depth > 0);
1147 	rqpair->current_recv_depth--;
1148 
1149 	/* Build the response which consists of optional
1150 	 * RDMA WRITEs to transfer data, plus an RDMA SEND
1151 	 * containing the response.
1152 	 */
1153 	first = &rdma_req->rsp.wr;
1154 
1155 	if (rsp->status.sc != SPDK_NVME_SC_SUCCESS) {
1156 		/* On failure, data was not read from the controller. So clear the
1157 		 * number of outstanding data WRs to zero.
1158 		 */
1159 		rdma_req->num_outstanding_data_wr = 0;
1160 	} else if (req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1161 		first = &rdma_req->data.wr;
1162 		*data_posted = 1;
1163 		num_outstanding_data_wr = rdma_req->num_outstanding_data_wr;
1164 	}
1165 	if (spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, first)) {
1166 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1167 	}
1168 	if (rtransport->rdma_opts.no_wr_batching) {
1169 		_poller_submit_sends(rtransport, rqpair->poller);
1170 	}
1171 
1172 	/* +1 for the rsp wr */
1173 	rqpair->current_send_depth += num_outstanding_data_wr + 1;
1174 
1175 	return 0;
1176 }
1177 
1178 static int
1179 nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
1180 {
1181 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
1182 	struct rdma_conn_param				ctrlr_event_data = {};
1183 	int						rc;
1184 
1185 	accept_data.recfmt = 0;
1186 	accept_data.crqsize = rqpair->max_queue_depth;
1187 
1188 	ctrlr_event_data.private_data = &accept_data;
1189 	ctrlr_event_data.private_data_len = sizeof(accept_data);
1190 	if (id->ps == RDMA_PS_TCP) {
1191 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
1192 		ctrlr_event_data.initiator_depth = rqpair->max_read_depth;
1193 	}
1194 
1195 	/* Configure infinite retries for the initiator side qpair.
1196 	 * When using a shared receive queue on the target side,
1197 	 * we need to pass this value to the initiator to prevent the
1198 	 * initiator side NIC from completing SEND requests back to the
1199 	 * initiator with status rnr_retry_count_exceeded. */
1200 	if (rqpair->srq != NULL) {
1201 		ctrlr_event_data.rnr_retry_count = 0x7;
1202 	}
1203 
1204 	/* When qpair is created without use of rdma cm API, an additional
1205 	 * information must be provided to initiator in the connection response:
1206 	 * whether qpair is using SRQ and its qp_num
1207 	 * Fields below are ignored by rdma cm if qpair has been
1208 	 * created using rdma cm API. */
1209 	ctrlr_event_data.srq = rqpair->srq ? 1 : 0;
1210 	ctrlr_event_data.qp_num = rqpair->rdma_qp->qp->qp_num;
1211 
1212 	rc = spdk_rdma_qp_accept(rqpair->rdma_qp, &ctrlr_event_data);
1213 	if (rc) {
1214 		SPDK_ERRLOG("Error %d on spdk_rdma_qp_accept\n", errno);
1215 	} else {
1216 		SPDK_DEBUGLOG(rdma, "Sent back the accept\n");
1217 	}
1218 
1219 	return rc;
1220 }
1221 
1222 static void
1223 nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
1224 {
1225 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
1226 
1227 	rej_data.recfmt = 0;
1228 	rej_data.sts = error;
1229 
1230 	rdma_reject(id, &rej_data, sizeof(rej_data));
1231 }
1232 
1233 static int
1234 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event)
1235 {
1236 	struct spdk_nvmf_rdma_transport *rtransport;
1237 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
1238 	struct spdk_nvmf_rdma_port	*port;
1239 	struct rdma_conn_param		*rdma_param = NULL;
1240 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
1241 	uint16_t			max_queue_depth;
1242 	uint16_t			max_read_depth;
1243 
1244 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1245 
1246 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
1247 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
1248 
1249 	rdma_param = &event->param.conn;
1250 	if (rdma_param->private_data == NULL ||
1251 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1252 		SPDK_ERRLOG("connect request: no private data provided\n");
1253 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
1254 		return -1;
1255 	}
1256 
1257 	private_data = rdma_param->private_data;
1258 	if (private_data->recfmt != 0) {
1259 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
1260 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
1261 		return -1;
1262 	}
1263 
1264 	SPDK_DEBUGLOG(rdma, "Connect Recv on fabric intf name %s, dev_name %s\n",
1265 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
1266 
1267 	port = event->listen_id->context;
1268 	SPDK_DEBUGLOG(rdma, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
1269 		      event->listen_id, event->listen_id->verbs, port);
1270 
1271 	/* Figure out the supported queue depth. This is a multi-step process
1272 	 * that takes into account hardware maximums, host provided values,
1273 	 * and our target's internal memory limits */
1274 
1275 	SPDK_DEBUGLOG(rdma, "Calculating Queue Depth\n");
1276 
1277 	/* Start with the maximum queue depth allowed by the target */
1278 	max_queue_depth = rtransport->transport.opts.max_queue_depth;
1279 	max_read_depth = rtransport->transport.opts.max_queue_depth;
1280 	SPDK_DEBUGLOG(rdma, "Target Max Queue Depth: %d\n",
1281 		      rtransport->transport.opts.max_queue_depth);
1282 
1283 	/* Next check the local NIC's hardware limitations */
1284 	SPDK_DEBUGLOG(rdma,
1285 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
1286 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
1287 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
1288 	max_read_depth = spdk_min(max_read_depth, port->device->attr.max_qp_init_rd_atom);
1289 
1290 	/* Next check the remote NIC's hardware limitations */
1291 	SPDK_DEBUGLOG(rdma,
1292 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
1293 		      rdma_param->initiator_depth, rdma_param->responder_resources);
1294 	if (rdma_param->initiator_depth > 0) {
1295 		max_read_depth = spdk_min(max_read_depth, rdma_param->initiator_depth);
1296 	}
1297 
1298 	/* Finally check for the host software requested values, which are
1299 	 * optional. */
1300 	if (rdma_param->private_data != NULL &&
1301 	    rdma_param->private_data_len >= sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1302 		SPDK_DEBUGLOG(rdma, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1303 		SPDK_DEBUGLOG(rdma, "Host Send Queue Size: %d\n", private_data->hsqsize);
1304 		max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
1305 		max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
1306 	}
1307 
1308 	SPDK_DEBUGLOG(rdma, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
1309 		      max_queue_depth, max_read_depth);
1310 
1311 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
1312 	if (rqpair == NULL) {
1313 		SPDK_ERRLOG("Could not allocate new connection.\n");
1314 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1315 		return -1;
1316 	}
1317 
1318 	rqpair->device = port->device;
1319 	rqpair->max_queue_depth = max_queue_depth;
1320 	rqpair->max_read_depth = max_read_depth;
1321 	rqpair->cm_id = event->id;
1322 	rqpair->listen_id = event->listen_id;
1323 	rqpair->qpair.transport = transport;
1324 	STAILQ_INIT(&rqpair->ibv_events);
1325 	/* use qid from the private data to determine the qpair type
1326 	   qid will be set to the appropriate value when the controller is created */
1327 	rqpair->qpair.qid = private_data->qid;
1328 
1329 	event->id->context = &rqpair->qpair;
1330 
1331 	spdk_nvmf_tgt_new_qpair(transport->tgt, &rqpair->qpair);
1332 
1333 	return 0;
1334 }
1335 
1336 static inline void
1337 nvmf_rdma_setup_wr(struct ibv_send_wr *wr, struct ibv_send_wr *next,
1338 		   enum spdk_nvme_data_transfer xfer)
1339 {
1340 	if (xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1341 		wr->opcode = IBV_WR_RDMA_WRITE;
1342 		wr->send_flags = 0;
1343 		wr->next = next;
1344 	} else if (xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1345 		wr->opcode = IBV_WR_RDMA_READ;
1346 		wr->send_flags = IBV_SEND_SIGNALED;
1347 		wr->next = NULL;
1348 	} else {
1349 		assert(0);
1350 	}
1351 }
1352 
1353 static int
1354 nvmf_request_alloc_wrs(struct spdk_nvmf_rdma_transport *rtransport,
1355 		       struct spdk_nvmf_rdma_request *rdma_req,
1356 		       uint32_t num_sgl_descriptors)
1357 {
1358 	struct spdk_nvmf_rdma_request_data	*work_requests[SPDK_NVMF_MAX_SGL_ENTRIES];
1359 	struct spdk_nvmf_rdma_request_data	*current_data_wr;
1360 	uint32_t				i;
1361 
1362 	if (num_sgl_descriptors > SPDK_NVMF_MAX_SGL_ENTRIES) {
1363 		SPDK_ERRLOG("Requested too much entries (%u), the limit is %u\n",
1364 			    num_sgl_descriptors, SPDK_NVMF_MAX_SGL_ENTRIES);
1365 		return -EINVAL;
1366 	}
1367 
1368 	if (spdk_mempool_get_bulk(rtransport->data_wr_pool, (void **)work_requests, num_sgl_descriptors)) {
1369 		return -ENOMEM;
1370 	}
1371 
1372 	current_data_wr = &rdma_req->data;
1373 
1374 	for (i = 0; i < num_sgl_descriptors; i++) {
1375 		nvmf_rdma_setup_wr(&current_data_wr->wr, &work_requests[i]->wr, rdma_req->req.xfer);
1376 		current_data_wr->wr.next = &work_requests[i]->wr;
1377 		current_data_wr = work_requests[i];
1378 		current_data_wr->wr.sg_list = current_data_wr->sgl;
1379 		current_data_wr->wr.wr_id = rdma_req->data.wr.wr_id;
1380 	}
1381 
1382 	nvmf_rdma_setup_wr(&current_data_wr->wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1383 
1384 	return 0;
1385 }
1386 
1387 static inline void
1388 nvmf_rdma_setup_request(struct spdk_nvmf_rdma_request *rdma_req)
1389 {
1390 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1391 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1392 
1393 	wr->wr.rdma.rkey = sgl->keyed.key;
1394 	wr->wr.rdma.remote_addr = sgl->address;
1395 	nvmf_rdma_setup_wr(wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1396 }
1397 
1398 static inline void
1399 nvmf_rdma_update_remote_addr(struct spdk_nvmf_rdma_request *rdma_req, uint32_t num_wrs)
1400 {
1401 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1402 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1403 	uint32_t			i;
1404 	int				j;
1405 	uint64_t			remote_addr_offset = 0;
1406 
1407 	for (i = 0; i < num_wrs; ++i) {
1408 		wr->wr.rdma.rkey = sgl->keyed.key;
1409 		wr->wr.rdma.remote_addr = sgl->address + remote_addr_offset;
1410 		for (j = 0; j < wr->num_sge; ++j) {
1411 			remote_addr_offset += wr->sg_list[j].length;
1412 		}
1413 		wr = wr->next;
1414 	}
1415 }
1416 
1417 static int
1418 nvmf_rdma_fill_wr_sgl(struct spdk_nvmf_rdma_poll_group *rgroup,
1419 		      struct spdk_nvmf_rdma_device *device,
1420 		      struct spdk_nvmf_rdma_request *rdma_req,
1421 		      struct ibv_send_wr *wr,
1422 		      uint32_t total_length,
1423 		      uint32_t num_extra_wrs)
1424 {
1425 	struct spdk_rdma_memory_translation mem_translation;
1426 	struct spdk_dif_ctx *dif_ctx = NULL;
1427 	struct ibv_sge	*sg_ele;
1428 	struct iovec *iov;
1429 	uint32_t remaining_data_block = 0;
1430 	uint32_t lkey, remaining;
1431 	int rc;
1432 
1433 	if (spdk_unlikely(rdma_req->req.dif_enabled)) {
1434 		dif_ctx = &rdma_req->req.dif.dif_ctx;
1435 		remaining_data_block = dif_ctx->block_size - dif_ctx->md_size;
1436 	}
1437 
1438 	wr->num_sge = 0;
1439 
1440 	while (total_length && (num_extra_wrs || wr->num_sge < SPDK_NVMF_MAX_SGL_ENTRIES)) {
1441 		iov = &rdma_req->req.iov[rdma_req->iovpos];
1442 		rc = spdk_rdma_get_translation(device->map, iov->iov_base, iov->iov_len, &mem_translation);
1443 		if (spdk_unlikely(rc)) {
1444 			return false;
1445 		}
1446 
1447 		lkey = spdk_rdma_memory_translation_get_lkey(&mem_translation);
1448 		sg_ele = &wr->sg_list[wr->num_sge];
1449 		remaining = spdk_min((uint32_t)iov->iov_len - rdma_req->offset, total_length);
1450 
1451 		if (spdk_likely(!dif_ctx)) {
1452 			sg_ele->lkey = lkey;
1453 			sg_ele->addr = (uintptr_t)iov->iov_base + rdma_req->offset;
1454 			sg_ele->length = remaining;
1455 			SPDK_DEBUGLOG(rdma, "sge[%d] %p addr 0x%"PRIx64", len %u\n", wr->num_sge, sg_ele, sg_ele->addr,
1456 				      sg_ele->length);
1457 			rdma_req->offset += sg_ele->length;
1458 			total_length -= sg_ele->length;
1459 			wr->num_sge++;
1460 
1461 			if (rdma_req->offset == iov->iov_len) {
1462 				rdma_req->offset = 0;
1463 				rdma_req->iovpos++;
1464 			}
1465 		} else {
1466 			uint32_t data_block_size = dif_ctx->block_size - dif_ctx->md_size;
1467 			uint32_t md_size = dif_ctx->md_size;
1468 			uint32_t sge_len;
1469 
1470 			while (remaining) {
1471 				if (wr->num_sge >= SPDK_NVMF_MAX_SGL_ENTRIES) {
1472 					if (num_extra_wrs > 0 && wr->next) {
1473 						wr = wr->next;
1474 						wr->num_sge = 0;
1475 						sg_ele = &wr->sg_list[wr->num_sge];
1476 						num_extra_wrs--;
1477 					} else {
1478 						break;
1479 					}
1480 				}
1481 				sg_ele->lkey = lkey;
1482 				sg_ele->addr = (uintptr_t)((char *)iov->iov_base + rdma_req->offset);
1483 				sge_len = spdk_min(remaining, remaining_data_block);
1484 				sg_ele->length = sge_len;
1485 				SPDK_DEBUGLOG(rdma, "sge[%d] %p addr 0x%"PRIx64", len %u\n", wr->num_sge, sg_ele, sg_ele->addr,
1486 					      sg_ele->length);
1487 				remaining -= sge_len;
1488 				remaining_data_block -= sge_len;
1489 				rdma_req->offset += sge_len;
1490 				total_length -= sge_len;
1491 
1492 				sg_ele++;
1493 				wr->num_sge++;
1494 
1495 				if (remaining_data_block == 0) {
1496 					/* skip metadata */
1497 					rdma_req->offset += md_size;
1498 					total_length -= md_size;
1499 					/* Metadata that do not fit this IO buffer will be included in the next IO buffer */
1500 					remaining -= spdk_min(remaining, md_size);
1501 					remaining_data_block = data_block_size;
1502 				}
1503 
1504 				if (remaining == 0) {
1505 					/* By subtracting the size of the last IOV from the offset, we ensure that we skip
1506 					   the remaining metadata bits at the beginning of the next buffer */
1507 					rdma_req->offset -= spdk_min(iov->iov_len, rdma_req->offset);
1508 					rdma_req->iovpos++;
1509 				}
1510 			}
1511 		}
1512 	}
1513 
1514 	if (total_length) {
1515 		SPDK_ERRLOG("Not enough SG entries to hold data buffer\n");
1516 		return -EINVAL;
1517 	}
1518 
1519 	return 0;
1520 }
1521 
1522 static inline uint32_t
1523 nvmf_rdma_calc_num_wrs(uint32_t length, uint32_t io_unit_size, uint32_t block_size)
1524 {
1525 	/* estimate the number of SG entries and WRs needed to process the request */
1526 	uint32_t num_sge = 0;
1527 	uint32_t i;
1528 	uint32_t num_buffers = SPDK_CEIL_DIV(length, io_unit_size);
1529 
1530 	for (i = 0; i < num_buffers && length > 0; i++) {
1531 		uint32_t buffer_len = spdk_min(length, io_unit_size);
1532 		uint32_t num_sge_in_block = SPDK_CEIL_DIV(buffer_len, block_size);
1533 
1534 		if (num_sge_in_block * block_size > buffer_len) {
1535 			++num_sge_in_block;
1536 		}
1537 		num_sge += num_sge_in_block;
1538 		length -= buffer_len;
1539 	}
1540 	return SPDK_CEIL_DIV(num_sge, SPDK_NVMF_MAX_SGL_ENTRIES);
1541 }
1542 
1543 static int
1544 nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1545 			    struct spdk_nvmf_rdma_device *device,
1546 			    struct spdk_nvmf_rdma_request *rdma_req,
1547 			    uint32_t length)
1548 {
1549 	struct spdk_nvmf_rdma_qpair		*rqpair;
1550 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1551 	struct spdk_nvmf_request		*req = &rdma_req->req;
1552 	struct ibv_send_wr			*wr = &rdma_req->data.wr;
1553 	int					rc;
1554 	uint32_t				num_wrs = 1;
1555 
1556 	rqpair = SPDK_CONTAINEROF(req->qpair, struct spdk_nvmf_rdma_qpair, qpair);
1557 	rgroup = rqpair->poller->group;
1558 
1559 	/* rdma wr specifics */
1560 	nvmf_rdma_setup_request(rdma_req);
1561 
1562 	rc = spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport,
1563 					   length);
1564 	if (rc != 0) {
1565 		return rc;
1566 	}
1567 
1568 	assert(req->iovcnt <= rqpair->max_send_sge);
1569 
1570 	rdma_req->iovpos = 0;
1571 
1572 	if (spdk_unlikely(req->dif_enabled)) {
1573 		num_wrs = nvmf_rdma_calc_num_wrs(length, rtransport->transport.opts.io_unit_size,
1574 						 req->dif.dif_ctx.block_size);
1575 		if (num_wrs > 1) {
1576 			rc = nvmf_request_alloc_wrs(rtransport, rdma_req, num_wrs - 1);
1577 			if (rc != 0) {
1578 				goto err_exit;
1579 			}
1580 		}
1581 	}
1582 
1583 	rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, wr, length, num_wrs - 1);
1584 	if (spdk_unlikely(rc != 0)) {
1585 		goto err_exit;
1586 	}
1587 
1588 	if (spdk_unlikely(num_wrs > 1)) {
1589 		nvmf_rdma_update_remote_addr(rdma_req, num_wrs);
1590 	}
1591 
1592 	/* set the number of outstanding data WRs for this request. */
1593 	rdma_req->num_outstanding_data_wr = num_wrs;
1594 
1595 	return rc;
1596 
1597 err_exit:
1598 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1599 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1600 	req->iovcnt = 0;
1601 	return rc;
1602 }
1603 
1604 static int
1605 nvmf_rdma_request_fill_iovs_multi_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1606 				      struct spdk_nvmf_rdma_device *device,
1607 				      struct spdk_nvmf_rdma_request *rdma_req)
1608 {
1609 	struct spdk_nvmf_rdma_qpair		*rqpair;
1610 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1611 	struct ibv_send_wr			*current_wr;
1612 	struct spdk_nvmf_request		*req = &rdma_req->req;
1613 	struct spdk_nvme_sgl_descriptor		*inline_segment, *desc;
1614 	uint32_t				num_sgl_descriptors;
1615 	uint32_t				lengths[SPDK_NVMF_MAX_SGL_ENTRIES], total_length = 0;
1616 	uint32_t				i;
1617 	int					rc;
1618 
1619 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1620 	rgroup = rqpair->poller->group;
1621 
1622 	inline_segment = &req->cmd->nvme_cmd.dptr.sgl1;
1623 	assert(inline_segment->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT);
1624 	assert(inline_segment->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET);
1625 
1626 	num_sgl_descriptors = inline_segment->unkeyed.length / sizeof(struct spdk_nvme_sgl_descriptor);
1627 	assert(num_sgl_descriptors <= SPDK_NVMF_MAX_SGL_ENTRIES);
1628 
1629 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1630 	for (i = 0; i < num_sgl_descriptors; i++) {
1631 		if (spdk_likely(!req->dif_enabled)) {
1632 			lengths[i] = desc->keyed.length;
1633 		} else {
1634 			req->dif.orig_length += desc->keyed.length;
1635 			lengths[i] = spdk_dif_get_length_with_md(desc->keyed.length, &req->dif.dif_ctx);
1636 			req->dif.elba_length += lengths[i];
1637 		}
1638 		total_length += lengths[i];
1639 		desc++;
1640 	}
1641 
1642 	if (total_length > rtransport->transport.opts.max_io_size) {
1643 		SPDK_ERRLOG("Multi SGL length 0x%x exceeds max io size 0x%x\n",
1644 			    total_length, rtransport->transport.opts.max_io_size);
1645 		req->rsp->nvme_cpl.status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1646 		return -EINVAL;
1647 	}
1648 
1649 	if (nvmf_request_alloc_wrs(rtransport, rdma_req, num_sgl_descriptors - 1) != 0) {
1650 		return -ENOMEM;
1651 	}
1652 
1653 	rc = spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport, total_length);
1654 	if (rc != 0) {
1655 		nvmf_rdma_request_free_data(rdma_req, rtransport);
1656 		return rc;
1657 	}
1658 
1659 	/* The first WR must always be the embedded data WR. This is how we unwind them later. */
1660 	current_wr = &rdma_req->data.wr;
1661 	assert(current_wr != NULL);
1662 
1663 	req->length = 0;
1664 	rdma_req->iovpos = 0;
1665 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1666 	for (i = 0; i < num_sgl_descriptors; i++) {
1667 		/* The descriptors must be keyed data block descriptors with an address, not an offset. */
1668 		if (spdk_unlikely(desc->generic.type != SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK ||
1669 				  desc->keyed.subtype != SPDK_NVME_SGL_SUBTYPE_ADDRESS)) {
1670 			rc = -EINVAL;
1671 			goto err_exit;
1672 		}
1673 
1674 		rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, current_wr, lengths[i], 0);
1675 		if (rc != 0) {
1676 			rc = -ENOMEM;
1677 			goto err_exit;
1678 		}
1679 
1680 		req->length += desc->keyed.length;
1681 		current_wr->wr.rdma.rkey = desc->keyed.key;
1682 		current_wr->wr.rdma.remote_addr = desc->address;
1683 		current_wr = current_wr->next;
1684 		desc++;
1685 	}
1686 
1687 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1688 	/* Go back to the last descriptor in the list. */
1689 	desc--;
1690 	if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1691 		if (desc->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1692 			rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1693 			rdma_req->rsp.wr.imm_data = desc->keyed.key;
1694 		}
1695 	}
1696 #endif
1697 
1698 	rdma_req->num_outstanding_data_wr = num_sgl_descriptors;
1699 
1700 	return 0;
1701 
1702 err_exit:
1703 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1704 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1705 	return rc;
1706 }
1707 
1708 static int
1709 nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1710 			    struct spdk_nvmf_rdma_device *device,
1711 			    struct spdk_nvmf_rdma_request *rdma_req)
1712 {
1713 	struct spdk_nvmf_request		*req = &rdma_req->req;
1714 	struct spdk_nvme_cpl			*rsp;
1715 	struct spdk_nvme_sgl_descriptor		*sgl;
1716 	int					rc;
1717 	uint32_t				length;
1718 
1719 	rsp = &req->rsp->nvme_cpl;
1720 	sgl = &req->cmd->nvme_cmd.dptr.sgl1;
1721 
1722 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1723 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1724 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1725 
1726 		length = sgl->keyed.length;
1727 		if (length > rtransport->transport.opts.max_io_size) {
1728 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1729 				    length, rtransport->transport.opts.max_io_size);
1730 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1731 			return -1;
1732 		}
1733 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1734 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1735 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1736 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1737 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1738 			}
1739 		}
1740 #endif
1741 
1742 		/* fill request length and populate iovs */
1743 		req->length = length;
1744 
1745 		if (spdk_unlikely(req->dif_enabled)) {
1746 			req->dif.orig_length = length;
1747 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
1748 			req->dif.elba_length = length;
1749 		}
1750 
1751 		rc = nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req, length);
1752 		if (spdk_unlikely(rc < 0)) {
1753 			if (rc == -EINVAL) {
1754 				SPDK_ERRLOG("SGL length exceeds the max I/O size\n");
1755 				rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1756 				return -1;
1757 			}
1758 			/* No available buffers. Queue this request up. */
1759 			SPDK_DEBUGLOG(rdma, "No available large data buffers. Queueing request %p\n", rdma_req);
1760 			return 0;
1761 		}
1762 
1763 		/* backward compatible */
1764 		req->data = req->iov[0].iov_base;
1765 
1766 		SPDK_DEBUGLOG(rdma, "Request %p took %d buffer/s from central pool\n", rdma_req,
1767 			      req->iovcnt);
1768 
1769 		return 0;
1770 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1771 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1772 		uint64_t offset = sgl->address;
1773 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1774 
1775 		SPDK_DEBUGLOG(nvmf, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1776 			      offset, sgl->unkeyed.length);
1777 
1778 		if (offset > max_len) {
1779 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1780 				    offset, max_len);
1781 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1782 			return -1;
1783 		}
1784 		max_len -= (uint32_t)offset;
1785 
1786 		if (sgl->unkeyed.length > max_len) {
1787 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1788 				    sgl->unkeyed.length, max_len);
1789 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1790 			return -1;
1791 		}
1792 
1793 		rdma_req->num_outstanding_data_wr = 0;
1794 		req->data = rdma_req->recv->buf + offset;
1795 		req->data_from_pool = false;
1796 		req->length = sgl->unkeyed.length;
1797 
1798 		req->iov[0].iov_base = req->data;
1799 		req->iov[0].iov_len = req->length;
1800 		req->iovcnt = 1;
1801 
1802 		return 0;
1803 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT &&
1804 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1805 
1806 		rc = nvmf_rdma_request_fill_iovs_multi_sgl(rtransport, device, rdma_req);
1807 		if (rc == -ENOMEM) {
1808 			SPDK_DEBUGLOG(rdma, "No available large data buffers. Queueing request %p\n", rdma_req);
1809 			return 0;
1810 		} else if (rc == -EINVAL) {
1811 			SPDK_ERRLOG("Multi SGL element request length exceeds the max I/O size\n");
1812 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1813 			return -1;
1814 		}
1815 
1816 		/* backward compatible */
1817 		req->data = req->iov[0].iov_base;
1818 
1819 		SPDK_DEBUGLOG(rdma, "Request %p took %d buffer/s from central pool\n", rdma_req,
1820 			      req->iovcnt);
1821 
1822 		return 0;
1823 	}
1824 
1825 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1826 		    sgl->generic.type, sgl->generic.subtype);
1827 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1828 	return -1;
1829 }
1830 
1831 static void
1832 _nvmf_rdma_request_free(struct spdk_nvmf_rdma_request *rdma_req,
1833 			struct spdk_nvmf_rdma_transport	*rtransport)
1834 {
1835 	struct spdk_nvmf_rdma_qpair		*rqpair;
1836 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1837 
1838 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1839 	if (rdma_req->req.data_from_pool) {
1840 		rgroup = rqpair->poller->group;
1841 
1842 		spdk_nvmf_request_free_buffers(&rdma_req->req, &rgroup->group, &rtransport->transport);
1843 	}
1844 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1845 	rdma_req->req.length = 0;
1846 	rdma_req->req.iovcnt = 0;
1847 	rdma_req->req.data = NULL;
1848 	rdma_req->rsp.wr.next = NULL;
1849 	rdma_req->data.wr.next = NULL;
1850 	rdma_req->offset = 0;
1851 	memset(&rdma_req->req.dif, 0, sizeof(rdma_req->req.dif));
1852 	rqpair->qd--;
1853 
1854 	STAILQ_INSERT_HEAD(&rqpair->resources->free_queue, rdma_req, state_link);
1855 	rdma_req->state = RDMA_REQUEST_STATE_FREE;
1856 }
1857 
1858 bool
1859 nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
1860 			  struct spdk_nvmf_rdma_request *rdma_req)
1861 {
1862 	struct spdk_nvmf_rdma_qpair	*rqpair;
1863 	struct spdk_nvmf_rdma_device	*device;
1864 	struct spdk_nvmf_rdma_poll_group *rgroup;
1865 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
1866 	int				rc;
1867 	struct spdk_nvmf_rdma_recv	*rdma_recv;
1868 	enum spdk_nvmf_rdma_request_state prev_state;
1869 	bool				progress = false;
1870 	int				data_posted;
1871 	uint32_t			num_blocks;
1872 
1873 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1874 	device = rqpair->device;
1875 	rgroup = rqpair->poller->group;
1876 
1877 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
1878 
1879 	/* If the queue pair is in an error state, force the request to the completed state
1880 	 * to release resources. */
1881 	if (rqpair->ibv_state == IBV_QPS_ERR || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1882 		if (rdma_req->state == RDMA_REQUEST_STATE_NEED_BUFFER) {
1883 			STAILQ_REMOVE(&rgroup->group.pending_buf_queue, &rdma_req->req, spdk_nvmf_request, buf_link);
1884 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING) {
1885 			STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1886 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING) {
1887 			STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1888 		}
1889 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1890 	}
1891 
1892 	/* The loop here is to allow for several back-to-back state changes. */
1893 	do {
1894 		prev_state = rdma_req->state;
1895 
1896 		SPDK_DEBUGLOG(rdma, "Request %p entering state %d\n", rdma_req, prev_state);
1897 
1898 		switch (rdma_req->state) {
1899 		case RDMA_REQUEST_STATE_FREE:
1900 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
1901 			 * to escape this state. */
1902 			break;
1903 		case RDMA_REQUEST_STATE_NEW:
1904 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
1905 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
1906 			rdma_recv = rdma_req->recv;
1907 
1908 			/* The first element of the SGL is the NVMe command */
1909 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
1910 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
1911 
1912 			if (rqpair->ibv_state == IBV_QPS_ERR  || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1913 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1914 				break;
1915 			}
1916 
1917 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&rdma_req->req, &rdma_req->req.dif.dif_ctx))) {
1918 				rdma_req->req.dif_enabled = true;
1919 			}
1920 
1921 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1922 			rdma_req->rsp.wr.opcode = IBV_WR_SEND;
1923 			rdma_req->rsp.wr.imm_data = 0;
1924 #endif
1925 
1926 			/* The next state transition depends on the data transfer needs of this request. */
1927 			rdma_req->req.xfer = spdk_nvmf_req_get_xfer(&rdma_req->req);
1928 
1929 			if (spdk_unlikely(rdma_req->req.xfer == SPDK_NVME_DATA_BIDIRECTIONAL)) {
1930 				rsp->status.sct = SPDK_NVME_SCT_GENERIC;
1931 				rsp->status.sc = SPDK_NVME_SC_INVALID_OPCODE;
1932 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1933 				SPDK_DEBUGLOG(rdma, "Request %p: invalid xfer type (BIDIRECTIONAL)\n", rdma_req);
1934 				break;
1935 			}
1936 
1937 			/* If no data to transfer, ready to execute. */
1938 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
1939 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1940 				break;
1941 			}
1942 
1943 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
1944 			STAILQ_INSERT_TAIL(&rgroup->group.pending_buf_queue, &rdma_req->req, buf_link);
1945 			break;
1946 		case RDMA_REQUEST_STATE_NEED_BUFFER:
1947 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
1948 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
1949 
1950 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
1951 
1952 			if (&rdma_req->req != STAILQ_FIRST(&rgroup->group.pending_buf_queue)) {
1953 				/* This request needs to wait in line to obtain a buffer */
1954 				break;
1955 			}
1956 
1957 			/* Try to get a data buffer */
1958 			rc = nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
1959 			if (rc < 0) {
1960 				STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
1961 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1962 				break;
1963 			}
1964 
1965 			if (!rdma_req->req.data) {
1966 				/* No buffers available. */
1967 				rgroup->stat.pending_data_buffer++;
1968 				break;
1969 			}
1970 
1971 			STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
1972 
1973 			/* If data is transferring from host to controller and the data didn't
1974 			 * arrive using in capsule data, we need to do a transfer from the host.
1975 			 */
1976 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER &&
1977 			    rdma_req->req.data_from_pool) {
1978 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
1979 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
1980 				break;
1981 			}
1982 
1983 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1984 			break;
1985 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
1986 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING, 0, 0,
1987 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
1988 
1989 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_read_queue)) {
1990 				/* This request needs to wait in line to perform RDMA */
1991 				break;
1992 			}
1993 			if (rqpair->current_send_depth + rdma_req->num_outstanding_data_wr > rqpair->max_send_depth
1994 			    || rqpair->current_read_depth + rdma_req->num_outstanding_data_wr > rqpair->max_read_depth) {
1995 				/* We can only have so many WRs outstanding. we have to wait until some finish. */
1996 				rqpair->poller->stat.pending_rdma_read++;
1997 				break;
1998 			}
1999 
2000 			/* We have already verified that this request is the head of the queue. */
2001 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_read_queue, state_link);
2002 
2003 			rc = request_transfer_in(&rdma_req->req);
2004 			if (!rc) {
2005 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
2006 			} else {
2007 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
2008 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2009 			}
2010 			break;
2011 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2012 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2013 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2014 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
2015 			 * to escape this state. */
2016 			break;
2017 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
2018 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
2019 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2020 
2021 			if (spdk_unlikely(rdma_req->req.dif_enabled)) {
2022 				if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2023 					/* generate DIF for write operation */
2024 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2025 					assert(num_blocks > 0);
2026 
2027 					rc = spdk_dif_generate(rdma_req->req.iov, rdma_req->req.iovcnt,
2028 							       num_blocks, &rdma_req->req.dif.dif_ctx);
2029 					if (rc != 0) {
2030 						SPDK_ERRLOG("DIF generation failed\n");
2031 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2032 						spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2033 						break;
2034 					}
2035 				}
2036 
2037 				assert(rdma_req->req.dif.elba_length >= rdma_req->req.length);
2038 				/* set extended length before IO operation */
2039 				rdma_req->req.length = rdma_req->req.dif.elba_length;
2040 			}
2041 
2042 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
2043 			spdk_nvmf_request_exec(&rdma_req->req);
2044 			break;
2045 		case RDMA_REQUEST_STATE_EXECUTING:
2046 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
2047 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2048 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
2049 			 * to escape this state. */
2050 			break;
2051 		case RDMA_REQUEST_STATE_EXECUTED:
2052 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
2053 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2054 			if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
2055 			    rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2056 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_write_queue, rdma_req, state_link);
2057 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING;
2058 			} else {
2059 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2060 			}
2061 			if (spdk_unlikely(rdma_req->req.dif_enabled)) {
2062 				/* restore the original length */
2063 				rdma_req->req.length = rdma_req->req.dif.orig_length;
2064 
2065 				if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2066 					struct spdk_dif_error error_blk;
2067 
2068 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2069 
2070 					rc = spdk_dif_verify(rdma_req->req.iov, rdma_req->req.iovcnt, num_blocks,
2071 							     &rdma_req->req.dif.dif_ctx, &error_blk);
2072 					if (rc) {
2073 						struct spdk_nvme_cpl *rsp = &rdma_req->req.rsp->nvme_cpl;
2074 
2075 						SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n", error_blk.err_type,
2076 							    error_blk.err_offset);
2077 						rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2078 						rsp->status.sc = nvmf_rdma_dif_error_to_compl_status(error_blk.err_type);
2079 						rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2080 						STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2081 					}
2082 				}
2083 			}
2084 			break;
2085 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
2086 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING, 0, 0,
2087 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2088 
2089 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_write_queue)) {
2090 				/* This request needs to wait in line to perform RDMA */
2091 				break;
2092 			}
2093 			if ((rqpair->current_send_depth + rdma_req->num_outstanding_data_wr + 1) >
2094 			    rqpair->max_send_depth) {
2095 				/* We can only have so many WRs outstanding. we have to wait until some finish.
2096 				 * +1 since each request has an additional wr in the resp. */
2097 				rqpair->poller->stat.pending_rdma_write++;
2098 				break;
2099 			}
2100 
2101 			/* We have already verified that this request is the head of the queue. */
2102 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_write_queue, state_link);
2103 
2104 			/* The data transfer will be kicked off from
2105 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
2106 			 */
2107 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2108 			break;
2109 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
2110 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
2111 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2112 			rc = request_transfer_out(&rdma_req->req, &data_posted);
2113 			assert(rc == 0); /* No good way to handle this currently */
2114 			if (rc) {
2115 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2116 			} else {
2117 				rdma_req->state = data_posted ? RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
2118 						  RDMA_REQUEST_STATE_COMPLETING;
2119 			}
2120 			break;
2121 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2122 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2123 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2124 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2125 			 * to escape this state. */
2126 			break;
2127 		case RDMA_REQUEST_STATE_COMPLETING:
2128 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
2129 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2130 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2131 			 * to escape this state. */
2132 			break;
2133 		case RDMA_REQUEST_STATE_COMPLETED:
2134 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
2135 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2136 
2137 			rqpair->poller->stat.request_latency += spdk_get_ticks() - rdma_req->receive_tsc;
2138 			_nvmf_rdma_request_free(rdma_req, rtransport);
2139 			break;
2140 		case RDMA_REQUEST_NUM_STATES:
2141 		default:
2142 			assert(0);
2143 			break;
2144 		}
2145 
2146 		if (rdma_req->state != prev_state) {
2147 			progress = true;
2148 		}
2149 	} while (rdma_req->state != prev_state);
2150 
2151 	return progress;
2152 }
2153 
2154 /* Public API callbacks begin here */
2155 
2156 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
2157 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
2158 #define SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH 4096
2159 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
2160 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2161 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
2162 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
2163 #define SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS 4095
2164 #define SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE 32
2165 #define SPDK_NVMF_RDMA_DEFAULT_NO_SRQ false
2166 #define SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP false
2167 #define SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG 100
2168 #define SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC 1
2169 #define SPDK_NVMF_RDMA_DEFAULT_NO_WR_BATCHING false
2170 
2171 static void
2172 nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
2173 {
2174 	opts->max_queue_depth =		SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
2175 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2176 	opts->in_capsule_data_size =	SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
2177 	opts->max_io_size =		SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
2178 	opts->io_unit_size =		SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE;
2179 	opts->max_aq_depth =		SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
2180 	opts->num_shared_buffers =	SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS;
2181 	opts->buf_cache_size =		SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE;
2182 	opts->dif_insert_or_strip =	SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP;
2183 	opts->abort_timeout_sec =	SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC;
2184 	opts->transport_specific =      NULL;
2185 }
2186 
2187 static int nvmf_rdma_destroy(struct spdk_nvmf_transport *transport,
2188 			     spdk_nvmf_transport_destroy_done_cb cb_fn, void *cb_arg);
2189 
2190 static inline bool
2191 nvmf_rdma_is_rxe_device(struct spdk_nvmf_rdma_device *device)
2192 {
2193 	return device->attr.vendor_id == NVMF_RXE_VENDOR_ID_OLD ||
2194 	       device->attr.vendor_id == NVMF_RXE_VENDOR_ID_NEW;
2195 }
2196 
2197 static struct spdk_nvmf_transport *
2198 nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
2199 {
2200 	int rc;
2201 	struct spdk_nvmf_rdma_transport *rtransport;
2202 	struct spdk_nvmf_rdma_device	*device, *tmp;
2203 	struct ibv_context		**contexts;
2204 	uint32_t			i;
2205 	int				flag;
2206 	uint32_t			sge_count;
2207 	uint32_t			min_shared_buffers;
2208 	int				max_device_sge = SPDK_NVMF_MAX_SGL_ENTRIES;
2209 	pthread_mutexattr_t		attr;
2210 
2211 	rtransport = calloc(1, sizeof(*rtransport));
2212 	if (!rtransport) {
2213 		return NULL;
2214 	}
2215 
2216 	if (pthread_mutexattr_init(&attr)) {
2217 		SPDK_ERRLOG("pthread_mutexattr_init() failed\n");
2218 		free(rtransport);
2219 		return NULL;
2220 	}
2221 
2222 	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) {
2223 		SPDK_ERRLOG("pthread_mutexattr_settype() failed\n");
2224 		pthread_mutexattr_destroy(&attr);
2225 		free(rtransport);
2226 		return NULL;
2227 	}
2228 
2229 	if (pthread_mutex_init(&rtransport->lock, &attr)) {
2230 		SPDK_ERRLOG("pthread_mutex_init() failed\n");
2231 		pthread_mutexattr_destroy(&attr);
2232 		free(rtransport);
2233 		return NULL;
2234 	}
2235 
2236 	pthread_mutexattr_destroy(&attr);
2237 
2238 	TAILQ_INIT(&rtransport->devices);
2239 	TAILQ_INIT(&rtransport->ports);
2240 	TAILQ_INIT(&rtransport->poll_groups);
2241 
2242 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
2243 	rtransport->rdma_opts.num_cqe = DEFAULT_NVMF_RDMA_CQ_SIZE;
2244 	rtransport->rdma_opts.max_srq_depth = SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH;
2245 	rtransport->rdma_opts.no_srq = SPDK_NVMF_RDMA_DEFAULT_NO_SRQ;
2246 	rtransport->rdma_opts.acceptor_backlog = SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2247 	rtransport->rdma_opts.no_wr_batching = SPDK_NVMF_RDMA_DEFAULT_NO_WR_BATCHING;
2248 	if (opts->transport_specific != NULL &&
2249 	    spdk_json_decode_object_relaxed(opts->transport_specific, rdma_transport_opts_decoder,
2250 					    SPDK_COUNTOF(rdma_transport_opts_decoder),
2251 					    &rtransport->rdma_opts)) {
2252 		SPDK_ERRLOG("spdk_json_decode_object_relaxed failed\n");
2253 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2254 		return NULL;
2255 	}
2256 
2257 	SPDK_INFOLOG(rdma, "*** RDMA Transport Init ***\n"
2258 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
2259 		     "  max_io_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
2260 		     "  in_capsule_data_size=%d, max_aq_depth=%d,\n"
2261 		     "  num_shared_buffers=%d, num_cqe=%d, max_srq_depth=%d, no_srq=%d,"
2262 		     "  acceptor_backlog=%d, no_wr_batching=%d abort_timeout_sec=%d\n",
2263 		     opts->max_queue_depth,
2264 		     opts->max_io_size,
2265 		     opts->max_qpairs_per_ctrlr - 1,
2266 		     opts->io_unit_size,
2267 		     opts->in_capsule_data_size,
2268 		     opts->max_aq_depth,
2269 		     opts->num_shared_buffers,
2270 		     rtransport->rdma_opts.num_cqe,
2271 		     rtransport->rdma_opts.max_srq_depth,
2272 		     rtransport->rdma_opts.no_srq,
2273 		     rtransport->rdma_opts.acceptor_backlog,
2274 		     rtransport->rdma_opts.no_wr_batching,
2275 		     opts->abort_timeout_sec);
2276 
2277 	/* I/O unit size cannot be larger than max I/O size */
2278 	if (opts->io_unit_size > opts->max_io_size) {
2279 		opts->io_unit_size = opts->max_io_size;
2280 	}
2281 
2282 	if (rtransport->rdma_opts.acceptor_backlog <= 0) {
2283 		SPDK_ERRLOG("The acceptor backlog cannot be less than 1, setting to the default value of (%d).\n",
2284 			    SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG);
2285 		rtransport->rdma_opts.acceptor_backlog = SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2286 	}
2287 
2288 	if (opts->num_shared_buffers < (SPDK_NVMF_MAX_SGL_ENTRIES * 2)) {
2289 		SPDK_ERRLOG("The number of shared data buffers (%d) is less than"
2290 			    "the minimum number required to guarantee that forward progress can be made (%d)\n",
2291 			    opts->num_shared_buffers, (SPDK_NVMF_MAX_SGL_ENTRIES * 2));
2292 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2293 		return NULL;
2294 	}
2295 
2296 	min_shared_buffers = spdk_env_get_core_count() * opts->buf_cache_size;
2297 	if (min_shared_buffers > opts->num_shared_buffers) {
2298 		SPDK_ERRLOG("There are not enough buffers to satisfy"
2299 			    "per-poll group caches for each thread. (%" PRIu32 ")"
2300 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
2301 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
2302 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2303 		return NULL;
2304 	}
2305 
2306 	sge_count = opts->max_io_size / opts->io_unit_size;
2307 	if (sge_count > NVMF_DEFAULT_TX_SGE) {
2308 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
2309 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2310 		return NULL;
2311 	}
2312 
2313 	rtransport->event_channel = rdma_create_event_channel();
2314 	if (rtransport->event_channel == NULL) {
2315 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
2316 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2317 		return NULL;
2318 	}
2319 
2320 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
2321 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2322 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
2323 			    rtransport->event_channel->fd, spdk_strerror(errno));
2324 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2325 		return NULL;
2326 	}
2327 
2328 	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data",
2329 				   opts->max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES,
2330 				   sizeof(struct spdk_nvmf_rdma_request_data),
2331 				   SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
2332 				   SPDK_ENV_SOCKET_ID_ANY);
2333 	if (!rtransport->data_wr_pool) {
2334 		SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");
2335 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2336 		return NULL;
2337 	}
2338 
2339 	contexts = rdma_get_devices(NULL);
2340 	if (contexts == NULL) {
2341 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2342 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2343 		return NULL;
2344 	}
2345 
2346 	i = 0;
2347 	rc = 0;
2348 	while (contexts[i] != NULL) {
2349 		device = calloc(1, sizeof(*device));
2350 		if (!device) {
2351 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
2352 			rc = -ENOMEM;
2353 			break;
2354 		}
2355 		device->context = contexts[i];
2356 		rc = ibv_query_device(device->context, &device->attr);
2357 		if (rc < 0) {
2358 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2359 			free(device);
2360 			break;
2361 
2362 		}
2363 
2364 		max_device_sge = spdk_min(max_device_sge, device->attr.max_sge);
2365 
2366 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2367 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
2368 			SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
2369 			SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
2370 		}
2371 
2372 		/**
2373 		 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
2374 		 * The Soft-RoCE RXE driver does not currently support send with invalidate,
2375 		 * but incorrectly reports that it does. There are changes making their way
2376 		 * through the kernel now that will enable this feature. When they are merged,
2377 		 * we can conditionally enable this feature.
2378 		 *
2379 		 * TODO: enable this for versions of the kernel rxe driver that support it.
2380 		 */
2381 		if (nvmf_rdma_is_rxe_device(device)) {
2382 			device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
2383 		}
2384 #endif
2385 
2386 		/* set up device context async ev fd as NON_BLOCKING */
2387 		flag = fcntl(device->context->async_fd, F_GETFL);
2388 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
2389 		if (rc < 0) {
2390 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
2391 			free(device);
2392 			break;
2393 		}
2394 
2395 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
2396 		i++;
2397 
2398 		if (g_nvmf_hooks.get_ibv_pd) {
2399 			device->pd = g_nvmf_hooks.get_ibv_pd(NULL, device->context);
2400 		} else {
2401 			device->pd = ibv_alloc_pd(device->context);
2402 		}
2403 
2404 		if (!device->pd) {
2405 			SPDK_ERRLOG("Unable to allocate protection domain.\n");
2406 			rc = -ENOMEM;
2407 			break;
2408 		}
2409 
2410 		assert(device->map == NULL);
2411 
2412 		device->map = spdk_rdma_create_mem_map(device->pd, &g_nvmf_hooks);
2413 		if (!device->map) {
2414 			SPDK_ERRLOG("Unable to allocate memory map for listen address\n");
2415 			rc = -ENOMEM;
2416 			break;
2417 		}
2418 
2419 		assert(device->map != NULL);
2420 		assert(device->pd != NULL);
2421 	}
2422 	rdma_free_devices(contexts);
2423 
2424 	if (opts->io_unit_size * max_device_sge < opts->max_io_size) {
2425 		/* divide and round up. */
2426 		opts->io_unit_size = (opts->max_io_size + max_device_sge - 1) / max_device_sge;
2427 
2428 		/* round up to the nearest 4k. */
2429 		opts->io_unit_size = (opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT - 1) & ~NVMF_DATA_BUFFER_MASK;
2430 
2431 		opts->io_unit_size = spdk_max(opts->io_unit_size, SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
2432 		SPDK_NOTICELOG("Adjusting the io unit size to fit the device's maximum I/O size. New I/O unit size %u\n",
2433 			       opts->io_unit_size);
2434 	}
2435 
2436 	if (rc < 0) {
2437 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2438 		return NULL;
2439 	}
2440 
2441 	/* Set up poll descriptor array to monitor events from RDMA and IB
2442 	 * in a single poll syscall
2443 	 */
2444 	rtransport->npoll_fds = i + 1;
2445 	i = 0;
2446 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
2447 	if (rtransport->poll_fds == NULL) {
2448 		SPDK_ERRLOG("poll_fds allocation failed\n");
2449 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2450 		return NULL;
2451 	}
2452 
2453 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
2454 	rtransport->poll_fds[i++].events = POLLIN;
2455 
2456 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2457 		rtransport->poll_fds[i].fd = device->context->async_fd;
2458 		rtransport->poll_fds[i++].events = POLLIN;
2459 	}
2460 
2461 	return &rtransport->transport;
2462 }
2463 
2464 static void
2465 nvmf_rdma_dump_opts(struct spdk_nvmf_transport *transport, struct spdk_json_write_ctx *w)
2466 {
2467 	struct spdk_nvmf_rdma_transport	*rtransport;
2468 	assert(w != NULL);
2469 
2470 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2471 	spdk_json_write_named_uint32(w, "max_srq_depth", rtransport->rdma_opts.max_srq_depth);
2472 	spdk_json_write_named_bool(w, "no_srq", rtransport->rdma_opts.no_srq);
2473 	if (rtransport->rdma_opts.no_srq == true) {
2474 		spdk_json_write_named_int32(w, "num_cqe", rtransport->rdma_opts.num_cqe);
2475 	}
2476 	spdk_json_write_named_int32(w, "acceptor_backlog", rtransport->rdma_opts.acceptor_backlog);
2477 	spdk_json_write_named_bool(w, "no_wr_batching", rtransport->rdma_opts.no_wr_batching);
2478 }
2479 
2480 static int
2481 nvmf_rdma_destroy(struct spdk_nvmf_transport *transport,
2482 		  spdk_nvmf_transport_destroy_done_cb cb_fn, void *cb_arg)
2483 {
2484 	struct spdk_nvmf_rdma_transport	*rtransport;
2485 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
2486 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
2487 
2488 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2489 
2490 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
2491 		TAILQ_REMOVE(&rtransport->ports, port, link);
2492 		rdma_destroy_id(port->id);
2493 		free(port);
2494 	}
2495 
2496 	if (rtransport->poll_fds != NULL) {
2497 		free(rtransport->poll_fds);
2498 	}
2499 
2500 	if (rtransport->event_channel != NULL) {
2501 		rdma_destroy_event_channel(rtransport->event_channel);
2502 	}
2503 
2504 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
2505 		TAILQ_REMOVE(&rtransport->devices, device, link);
2506 		spdk_rdma_free_mem_map(&device->map);
2507 		if (device->pd) {
2508 			if (!g_nvmf_hooks.get_ibv_pd) {
2509 				ibv_dealloc_pd(device->pd);
2510 			}
2511 		}
2512 		free(device);
2513 	}
2514 
2515 	if (rtransport->data_wr_pool != NULL) {
2516 		if (spdk_mempool_count(rtransport->data_wr_pool) !=
2517 		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {
2518 			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",
2519 				    spdk_mempool_count(rtransport->data_wr_pool),
2520 				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);
2521 		}
2522 	}
2523 
2524 	spdk_mempool_free(rtransport->data_wr_pool);
2525 
2526 	pthread_mutex_destroy(&rtransport->lock);
2527 	free(rtransport);
2528 
2529 	if (cb_fn) {
2530 		cb_fn(cb_arg);
2531 	}
2532 	return 0;
2533 }
2534 
2535 static int
2536 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2537 			  struct spdk_nvme_transport_id *trid,
2538 			  bool peer);
2539 
2540 static int
2541 nvmf_rdma_listen(struct spdk_nvmf_transport *transport, const struct spdk_nvme_transport_id *trid,
2542 		 struct spdk_nvmf_listen_opts *listen_opts)
2543 {
2544 	struct spdk_nvmf_rdma_transport	*rtransport;
2545 	struct spdk_nvmf_rdma_device	*device;
2546 	struct spdk_nvmf_rdma_port	*port;
2547 	struct addrinfo			*res;
2548 	struct addrinfo			hints;
2549 	int				family;
2550 	int				rc;
2551 
2552 	if (!strlen(trid->trsvcid)) {
2553 		SPDK_ERRLOG("Service id is required\n");
2554 		return -EINVAL;
2555 	}
2556 
2557 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2558 	assert(rtransport->event_channel != NULL);
2559 
2560 	pthread_mutex_lock(&rtransport->lock);
2561 	port = calloc(1, sizeof(*port));
2562 	if (!port) {
2563 		SPDK_ERRLOG("Port allocation failed\n");
2564 		pthread_mutex_unlock(&rtransport->lock);
2565 		return -ENOMEM;
2566 	}
2567 
2568 	port->trid = trid;
2569 
2570 	switch (trid->adrfam) {
2571 	case SPDK_NVMF_ADRFAM_IPV4:
2572 		family = AF_INET;
2573 		break;
2574 	case SPDK_NVMF_ADRFAM_IPV6:
2575 		family = AF_INET6;
2576 		break;
2577 	default:
2578 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", trid->adrfam);
2579 		free(port);
2580 		pthread_mutex_unlock(&rtransport->lock);
2581 		return -EINVAL;
2582 	}
2583 
2584 	memset(&hints, 0, sizeof(hints));
2585 	hints.ai_family = family;
2586 	hints.ai_flags = AI_NUMERICSERV;
2587 	hints.ai_socktype = SOCK_STREAM;
2588 	hints.ai_protocol = 0;
2589 
2590 	rc = getaddrinfo(trid->traddr, trid->trsvcid, &hints, &res);
2591 	if (rc) {
2592 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
2593 		free(port);
2594 		pthread_mutex_unlock(&rtransport->lock);
2595 		return -EINVAL;
2596 	}
2597 
2598 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
2599 	if (rc < 0) {
2600 		SPDK_ERRLOG("rdma_create_id() failed\n");
2601 		freeaddrinfo(res);
2602 		free(port);
2603 		pthread_mutex_unlock(&rtransport->lock);
2604 		return rc;
2605 	}
2606 
2607 	rc = rdma_bind_addr(port->id, res->ai_addr);
2608 	freeaddrinfo(res);
2609 
2610 	if (rc < 0) {
2611 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
2612 		rdma_destroy_id(port->id);
2613 		free(port);
2614 		pthread_mutex_unlock(&rtransport->lock);
2615 		return rc;
2616 	}
2617 
2618 	if (!port->id->verbs) {
2619 		SPDK_ERRLOG("ibv_context is null\n");
2620 		rdma_destroy_id(port->id);
2621 		free(port);
2622 		pthread_mutex_unlock(&rtransport->lock);
2623 		return -1;
2624 	}
2625 
2626 	rc = rdma_listen(port->id, rtransport->rdma_opts.acceptor_backlog);
2627 	if (rc < 0) {
2628 		SPDK_ERRLOG("rdma_listen() failed\n");
2629 		rdma_destroy_id(port->id);
2630 		free(port);
2631 		pthread_mutex_unlock(&rtransport->lock);
2632 		return rc;
2633 	}
2634 
2635 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2636 		if (device->context == port->id->verbs) {
2637 			port->device = device;
2638 			break;
2639 		}
2640 	}
2641 	if (!port->device) {
2642 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
2643 			    port->id->verbs);
2644 		rdma_destroy_id(port->id);
2645 		free(port);
2646 		pthread_mutex_unlock(&rtransport->lock);
2647 		return -EINVAL;
2648 	}
2649 
2650 	SPDK_NOTICELOG("*** NVMe/RDMA Target Listening on %s port %s ***\n",
2651 		       trid->traddr, trid->trsvcid);
2652 
2653 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
2654 	pthread_mutex_unlock(&rtransport->lock);
2655 	return 0;
2656 }
2657 
2658 static void
2659 nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
2660 		      const struct spdk_nvme_transport_id *trid)
2661 {
2662 	struct spdk_nvmf_rdma_transport *rtransport;
2663 	struct spdk_nvmf_rdma_port *port, *tmp;
2664 
2665 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2666 
2667 	pthread_mutex_lock(&rtransport->lock);
2668 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
2669 		if (spdk_nvme_transport_id_compare(port->trid, trid) == 0) {
2670 			TAILQ_REMOVE(&rtransport->ports, port, link);
2671 			rdma_destroy_id(port->id);
2672 			free(port);
2673 			break;
2674 		}
2675 	}
2676 
2677 	pthread_mutex_unlock(&rtransport->lock);
2678 }
2679 
2680 static void
2681 nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
2682 				struct spdk_nvmf_rdma_qpair *rqpair, bool drain)
2683 {
2684 	struct spdk_nvmf_request *req, *tmp;
2685 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
2686 	struct spdk_nvmf_rdma_resources *resources;
2687 
2688 	/* We process I/O in the data transfer pending queue at the highest priority. RDMA reads first */
2689 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_read_queue, state_link, req_tmp) {
2690 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2691 			break;
2692 		}
2693 	}
2694 
2695 	/* Then RDMA writes since reads have stronger restrictions than writes */
2696 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_write_queue, state_link, req_tmp) {
2697 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2698 			break;
2699 		}
2700 	}
2701 
2702 	/* Then we handle request waiting on memory buffers. */
2703 	STAILQ_FOREACH_SAFE(req, &rqpair->poller->group->group.pending_buf_queue, buf_link, tmp) {
2704 		rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
2705 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2706 			break;
2707 		}
2708 	}
2709 
2710 	resources = rqpair->resources;
2711 	while (!STAILQ_EMPTY(&resources->free_queue) && !STAILQ_EMPTY(&resources->incoming_queue)) {
2712 		rdma_req = STAILQ_FIRST(&resources->free_queue);
2713 		STAILQ_REMOVE_HEAD(&resources->free_queue, state_link);
2714 		rdma_req->recv = STAILQ_FIRST(&resources->incoming_queue);
2715 		STAILQ_REMOVE_HEAD(&resources->incoming_queue, link);
2716 
2717 		if (rqpair->srq != NULL) {
2718 			rdma_req->req.qpair = &rdma_req->recv->qpair->qpair;
2719 			rdma_req->recv->qpair->qd++;
2720 		} else {
2721 			rqpair->qd++;
2722 		}
2723 
2724 		rdma_req->receive_tsc = rdma_req->recv->receive_tsc;
2725 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
2726 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false) {
2727 			break;
2728 		}
2729 	}
2730 	if (!STAILQ_EMPTY(&resources->incoming_queue) && STAILQ_EMPTY(&resources->free_queue)) {
2731 		rqpair->poller->stat.pending_free_request++;
2732 	}
2733 }
2734 
2735 static inline bool
2736 nvmf_rdma_can_ignore_last_wqe_reached(struct spdk_nvmf_rdma_device *device)
2737 {
2738 	/* iWARP transport and SoftRoCE driver don't support LAST_WQE_REACHED ibv async event */
2739 	return nvmf_rdma_is_rxe_device(device) ||
2740 	       device->context->device->transport_type == IBV_TRANSPORT_IWARP;
2741 }
2742 
2743 static void
2744 nvmf_rdma_destroy_drained_qpair(struct spdk_nvmf_rdma_qpair *rqpair)
2745 {
2746 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
2747 			struct spdk_nvmf_rdma_transport, transport);
2748 
2749 	nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
2750 
2751 	/* nvmr_rdma_close_qpair is not called */
2752 	if (!rqpair->to_close) {
2753 		return;
2754 	}
2755 
2756 	/* In non SRQ path, we will reach rqpair->max_queue_depth. In SRQ path, we will get the last_wqe event. */
2757 	if (rqpair->current_send_depth != 0) {
2758 		return;
2759 	}
2760 
2761 	if (rqpair->srq == NULL && rqpair->current_recv_depth != rqpair->max_queue_depth) {
2762 		return;
2763 	}
2764 
2765 	if (rqpair->srq != NULL && rqpair->last_wqe_reached == false &&
2766 	    !nvmf_rdma_can_ignore_last_wqe_reached(rqpair->device)) {
2767 		return;
2768 	}
2769 
2770 	assert(rqpair->qpair.state == SPDK_NVMF_QPAIR_ERROR);
2771 
2772 	nvmf_rdma_qpair_destroy(rqpair);
2773 }
2774 
2775 static int
2776 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
2777 {
2778 	struct spdk_nvmf_qpair		*qpair;
2779 	struct spdk_nvmf_rdma_qpair	*rqpair;
2780 
2781 	if (evt->id == NULL) {
2782 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
2783 		return -1;
2784 	}
2785 
2786 	qpair = evt->id->context;
2787 	if (qpair == NULL) {
2788 		SPDK_ERRLOG("disconnect request: no active connection\n");
2789 		return -1;
2790 	}
2791 
2792 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2793 
2794 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair);
2795 
2796 	spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2797 
2798 	return 0;
2799 }
2800 
2801 #ifdef DEBUG
2802 static const char *CM_EVENT_STR[] = {
2803 	"RDMA_CM_EVENT_ADDR_RESOLVED",
2804 	"RDMA_CM_EVENT_ADDR_ERROR",
2805 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
2806 	"RDMA_CM_EVENT_ROUTE_ERROR",
2807 	"RDMA_CM_EVENT_CONNECT_REQUEST",
2808 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
2809 	"RDMA_CM_EVENT_CONNECT_ERROR",
2810 	"RDMA_CM_EVENT_UNREACHABLE",
2811 	"RDMA_CM_EVENT_REJECTED",
2812 	"RDMA_CM_EVENT_ESTABLISHED",
2813 	"RDMA_CM_EVENT_DISCONNECTED",
2814 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
2815 	"RDMA_CM_EVENT_MULTICAST_JOIN",
2816 	"RDMA_CM_EVENT_MULTICAST_ERROR",
2817 	"RDMA_CM_EVENT_ADDR_CHANGE",
2818 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
2819 };
2820 #endif /* DEBUG */
2821 
2822 static void
2823 nvmf_rdma_disconnect_qpairs_on_port(struct spdk_nvmf_rdma_transport *rtransport,
2824 				    struct spdk_nvmf_rdma_port *port)
2825 {
2826 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2827 	struct spdk_nvmf_rdma_poller		*rpoller;
2828 	struct spdk_nvmf_rdma_qpair		*rqpair;
2829 
2830 	TAILQ_FOREACH(rgroup, &rtransport->poll_groups, link) {
2831 		TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
2832 			TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
2833 				if (rqpair->listen_id == port->id) {
2834 					spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2835 				}
2836 			}
2837 		}
2838 	}
2839 }
2840 
2841 static bool
2842 nvmf_rdma_handle_cm_event_addr_change(struct spdk_nvmf_transport *transport,
2843 				      struct rdma_cm_event *event)
2844 {
2845 	const struct spdk_nvme_transport_id	*trid;
2846 	struct spdk_nvmf_rdma_port		*port;
2847 	struct spdk_nvmf_rdma_transport		*rtransport;
2848 	bool					event_acked = false;
2849 
2850 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2851 	TAILQ_FOREACH(port, &rtransport->ports, link) {
2852 		if (port->id == event->id) {
2853 			SPDK_ERRLOG("ADDR_CHANGE: IP %s:%s migrated\n", port->trid->traddr, port->trid->trsvcid);
2854 			rdma_ack_cm_event(event);
2855 			event_acked = true;
2856 			trid = port->trid;
2857 			break;
2858 		}
2859 	}
2860 
2861 	if (event_acked) {
2862 		nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
2863 
2864 		nvmf_rdma_stop_listen(transport, trid);
2865 		nvmf_rdma_listen(transport, trid, NULL);
2866 	}
2867 
2868 	return event_acked;
2869 }
2870 
2871 static void
2872 nvmf_rdma_handle_cm_event_port_removal(struct spdk_nvmf_transport *transport,
2873 				       struct rdma_cm_event *event)
2874 {
2875 	struct spdk_nvmf_rdma_port		*port;
2876 	struct spdk_nvmf_rdma_transport		*rtransport;
2877 
2878 	port = event->id->context;
2879 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2880 
2881 	SPDK_NOTICELOG("Port %s:%s is being removed\n", port->trid->traddr, port->trid->trsvcid);
2882 
2883 	nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
2884 
2885 	rdma_ack_cm_event(event);
2886 
2887 	while (spdk_nvmf_transport_stop_listen(transport, port->trid) == 0) {
2888 		;
2889 	}
2890 }
2891 
2892 static void
2893 nvmf_process_cm_event(struct spdk_nvmf_transport *transport)
2894 {
2895 	struct spdk_nvmf_rdma_transport *rtransport;
2896 	struct rdma_cm_event		*event;
2897 	int				rc;
2898 	bool				event_acked;
2899 
2900 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2901 
2902 	if (rtransport->event_channel == NULL) {
2903 		return;
2904 	}
2905 
2906 	while (1) {
2907 		event_acked = false;
2908 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
2909 		if (rc) {
2910 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
2911 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
2912 			}
2913 			break;
2914 		}
2915 
2916 		SPDK_DEBUGLOG(rdma, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
2917 
2918 		spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
2919 
2920 		switch (event->event) {
2921 		case RDMA_CM_EVENT_ADDR_RESOLVED:
2922 		case RDMA_CM_EVENT_ADDR_ERROR:
2923 		case RDMA_CM_EVENT_ROUTE_RESOLVED:
2924 		case RDMA_CM_EVENT_ROUTE_ERROR:
2925 			/* No action required. The target never attempts to resolve routes. */
2926 			break;
2927 		case RDMA_CM_EVENT_CONNECT_REQUEST:
2928 			rc = nvmf_rdma_connect(transport, event);
2929 			if (rc < 0) {
2930 				SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
2931 				break;
2932 			}
2933 			break;
2934 		case RDMA_CM_EVENT_CONNECT_RESPONSE:
2935 			/* The target never initiates a new connection. So this will not occur. */
2936 			break;
2937 		case RDMA_CM_EVENT_CONNECT_ERROR:
2938 			/* Can this happen? The docs say it can, but not sure what causes it. */
2939 			break;
2940 		case RDMA_CM_EVENT_UNREACHABLE:
2941 		case RDMA_CM_EVENT_REJECTED:
2942 			/* These only occur on the client side. */
2943 			break;
2944 		case RDMA_CM_EVENT_ESTABLISHED:
2945 			/* TODO: Should we be waiting for this event anywhere? */
2946 			break;
2947 		case RDMA_CM_EVENT_DISCONNECTED:
2948 			rc = nvmf_rdma_disconnect(event);
2949 			if (rc < 0) {
2950 				SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2951 				break;
2952 			}
2953 			break;
2954 		case RDMA_CM_EVENT_DEVICE_REMOVAL:
2955 			/* In case of device removal, kernel IB part triggers IBV_EVENT_DEVICE_FATAL
2956 			 * which triggers RDMA_CM_EVENT_DEVICE_REMOVAL on all cma_id’s.
2957 			 * Once these events are sent to SPDK, we should release all IB resources and
2958 			 * don't make attempts to call any ibv_query/modify/create functions. We can only call
2959 			 * ibv_destory* functions to release user space memory allocated by IB. All kernel
2960 			 * resources are already cleaned. */
2961 			if (event->id->qp) {
2962 				/* If rdma_cm event has a valid `qp` pointer then the event refers to the
2963 				 * corresponding qpair. Otherwise the event refers to a listening device */
2964 				rc = nvmf_rdma_disconnect(event);
2965 				if (rc < 0) {
2966 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2967 					break;
2968 				}
2969 			} else {
2970 				nvmf_rdma_handle_cm_event_port_removal(transport, event);
2971 				event_acked = true;
2972 			}
2973 			break;
2974 		case RDMA_CM_EVENT_MULTICAST_JOIN:
2975 		case RDMA_CM_EVENT_MULTICAST_ERROR:
2976 			/* Multicast is not used */
2977 			break;
2978 		case RDMA_CM_EVENT_ADDR_CHANGE:
2979 			event_acked = nvmf_rdma_handle_cm_event_addr_change(transport, event);
2980 			break;
2981 		case RDMA_CM_EVENT_TIMEWAIT_EXIT:
2982 			/* For now, do nothing. The target never re-uses queue pairs. */
2983 			break;
2984 		default:
2985 			SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
2986 			break;
2987 		}
2988 		if (!event_acked) {
2989 			rdma_ack_cm_event(event);
2990 		}
2991 	}
2992 }
2993 
2994 static void
2995 nvmf_rdma_handle_last_wqe_reached(struct spdk_nvmf_rdma_qpair *rqpair)
2996 {
2997 	rqpair->last_wqe_reached = true;
2998 	nvmf_rdma_destroy_drained_qpair(rqpair);
2999 }
3000 
3001 static void
3002 nvmf_rdma_qpair_process_ibv_event(void *ctx)
3003 {
3004 	struct spdk_nvmf_rdma_ibv_event_ctx *event_ctx = ctx;
3005 
3006 	if (event_ctx->rqpair) {
3007 		STAILQ_REMOVE(&event_ctx->rqpair->ibv_events, event_ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3008 		if (event_ctx->cb_fn) {
3009 			event_ctx->cb_fn(event_ctx->rqpair);
3010 		}
3011 	}
3012 	free(event_ctx);
3013 }
3014 
3015 static int
3016 nvmf_rdma_send_qpair_async_event(struct spdk_nvmf_rdma_qpair *rqpair,
3017 				 spdk_nvmf_rdma_qpair_ibv_event fn)
3018 {
3019 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx;
3020 	struct spdk_thread *thr = NULL;
3021 	int rc;
3022 
3023 	if (rqpair->qpair.group) {
3024 		thr = rqpair->qpair.group->thread;
3025 	} else if (rqpair->destruct_channel) {
3026 		thr = spdk_io_channel_get_thread(rqpair->destruct_channel);
3027 	}
3028 
3029 	if (!thr) {
3030 		SPDK_DEBUGLOG(rdma, "rqpair %p has no thread\n", rqpair);
3031 		return -EINVAL;
3032 	}
3033 
3034 	ctx = calloc(1, sizeof(*ctx));
3035 	if (!ctx) {
3036 		return -ENOMEM;
3037 	}
3038 
3039 	ctx->rqpair = rqpair;
3040 	ctx->cb_fn = fn;
3041 	STAILQ_INSERT_TAIL(&rqpair->ibv_events, ctx, link);
3042 
3043 	rc = spdk_thread_send_msg(thr, nvmf_rdma_qpair_process_ibv_event, ctx);
3044 	if (rc) {
3045 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3046 		free(ctx);
3047 	}
3048 
3049 	return rc;
3050 }
3051 
3052 static int
3053 nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
3054 {
3055 	int				rc;
3056 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
3057 	struct ibv_async_event		event;
3058 
3059 	rc = ibv_get_async_event(device->context, &event);
3060 
3061 	if (rc) {
3062 		/* In non-blocking mode -1 means there are no events available */
3063 		return rc;
3064 	}
3065 
3066 	switch (event.event_type) {
3067 	case IBV_EVENT_QP_FATAL:
3068 		rqpair = event.element.qp->qp_context;
3069 		SPDK_ERRLOG("Fatal event received for rqpair %p\n", rqpair);
3070 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3071 				  (uintptr_t)rqpair, event.event_type);
3072 		nvmf_rdma_update_ibv_state(rqpair);
3073 		spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3074 		break;
3075 	case IBV_EVENT_QP_LAST_WQE_REACHED:
3076 		/* This event only occurs for shared receive queues. */
3077 		rqpair = event.element.qp->qp_context;
3078 		SPDK_DEBUGLOG(rdma, "Last WQE reached event received for rqpair %p\n", rqpair);
3079 		rc = nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_last_wqe_reached);
3080 		if (rc) {
3081 			SPDK_WARNLOG("Failed to send LAST_WQE_REACHED event. rqpair %p, err %d\n", rqpair, rc);
3082 			rqpair->last_wqe_reached = true;
3083 		}
3084 		break;
3085 	case IBV_EVENT_SQ_DRAINED:
3086 		/* This event occurs frequently in both error and non-error states.
3087 		 * Check if the qpair is in an error state before sending a message. */
3088 		rqpair = event.element.qp->qp_context;
3089 		SPDK_DEBUGLOG(rdma, "Last sq drained event received for rqpair %p\n", rqpair);
3090 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3091 				  (uintptr_t)rqpair, event.event_type);
3092 		if (nvmf_rdma_update_ibv_state(rqpair) == IBV_QPS_ERR) {
3093 			spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3094 		}
3095 		break;
3096 	case IBV_EVENT_QP_REQ_ERR:
3097 	case IBV_EVENT_QP_ACCESS_ERR:
3098 	case IBV_EVENT_COMM_EST:
3099 	case IBV_EVENT_PATH_MIG:
3100 	case IBV_EVENT_PATH_MIG_ERR:
3101 		SPDK_NOTICELOG("Async event: %s\n",
3102 			       ibv_event_type_str(event.event_type));
3103 		rqpair = event.element.qp->qp_context;
3104 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3105 				  (uintptr_t)rqpair, event.event_type);
3106 		nvmf_rdma_update_ibv_state(rqpair);
3107 		break;
3108 	case IBV_EVENT_CQ_ERR:
3109 	case IBV_EVENT_DEVICE_FATAL:
3110 	case IBV_EVENT_PORT_ACTIVE:
3111 	case IBV_EVENT_PORT_ERR:
3112 	case IBV_EVENT_LID_CHANGE:
3113 	case IBV_EVENT_PKEY_CHANGE:
3114 	case IBV_EVENT_SM_CHANGE:
3115 	case IBV_EVENT_SRQ_ERR:
3116 	case IBV_EVENT_SRQ_LIMIT_REACHED:
3117 	case IBV_EVENT_CLIENT_REREGISTER:
3118 	case IBV_EVENT_GID_CHANGE:
3119 	default:
3120 		SPDK_NOTICELOG("Async event: %s\n",
3121 			       ibv_event_type_str(event.event_type));
3122 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
3123 		break;
3124 	}
3125 	ibv_ack_async_event(&event);
3126 
3127 	return 0;
3128 }
3129 
3130 static void
3131 nvmf_process_ib_events(struct spdk_nvmf_rdma_device *device, uint32_t max_events)
3132 {
3133 	int rc = 0;
3134 	uint32_t i = 0;
3135 
3136 	for (i = 0; i < max_events; i++) {
3137 		rc = nvmf_process_ib_event(device);
3138 		if (rc) {
3139 			break;
3140 		}
3141 	}
3142 
3143 	SPDK_DEBUGLOG(rdma, "Device %s: %u events processed\n", device->context->device->name, i);
3144 }
3145 
3146 static uint32_t
3147 nvmf_rdma_accept(struct spdk_nvmf_transport *transport)
3148 {
3149 	int	nfds, i = 0;
3150 	struct spdk_nvmf_rdma_transport *rtransport;
3151 	struct spdk_nvmf_rdma_device *device, *tmp;
3152 	uint32_t count;
3153 
3154 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3155 	count = nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
3156 
3157 	if (nfds <= 0) {
3158 		return 0;
3159 	}
3160 
3161 	/* The first poll descriptor is RDMA CM event */
3162 	if (rtransport->poll_fds[i++].revents & POLLIN) {
3163 		nvmf_process_cm_event(transport);
3164 		nfds--;
3165 	}
3166 
3167 	if (nfds == 0) {
3168 		return count;
3169 	}
3170 
3171 	/* Second and subsequent poll descriptors are IB async events */
3172 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
3173 		if (rtransport->poll_fds[i++].revents & POLLIN) {
3174 			nvmf_process_ib_events(device, 32);
3175 			nfds--;
3176 		}
3177 	}
3178 	/* check all flagged fd's have been served */
3179 	assert(nfds == 0);
3180 
3181 	return count;
3182 }
3183 
3184 static void
3185 nvmf_rdma_cdata_init(struct spdk_nvmf_transport *transport, struct spdk_nvmf_subsystem *subsystem,
3186 		     struct spdk_nvmf_ctrlr_data *cdata)
3187 {
3188 	cdata->nvmf_specific.msdbd = SPDK_NVMF_MAX_SGL_ENTRIES;
3189 
3190 	/* Disable in-capsule data transfer for RDMA controller when dif_insert_or_strip is enabled
3191 	since in-capsule data only works with NVME drives that support SGL memory layout */
3192 	if (transport->opts.dif_insert_or_strip) {
3193 		cdata->nvmf_specific.ioccsz = sizeof(struct spdk_nvme_cmd) / 16;
3194 	}
3195 
3196 	if (cdata->nvmf_specific.ioccsz > ((sizeof(struct spdk_nvme_cmd) + 0x1000) / 16)) {
3197 		SPDK_WARNLOG("RDMA is configured to support up to 16 SGL entries while in capsule"
3198 			     " data is greater than 4KiB.\n");
3199 		SPDK_WARNLOG("When used in conjunction with the NVMe-oF initiator from the Linux "
3200 			     "kernel between versions 5.4 and 5.12 data corruption may occur for "
3201 			     "writes that are not a multiple of 4KiB in size.\n");
3202 	}
3203 }
3204 
3205 static void
3206 nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
3207 		   struct spdk_nvme_transport_id *trid,
3208 		   struct spdk_nvmf_discovery_log_page_entry *entry)
3209 {
3210 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
3211 	entry->adrfam = trid->adrfam;
3212 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
3213 
3214 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
3215 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
3216 
3217 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
3218 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
3219 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
3220 }
3221 
3222 static void
3223 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
3224 
3225 static struct spdk_nvmf_transport_poll_group *
3226 nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
3227 {
3228 	struct spdk_nvmf_rdma_transport		*rtransport;
3229 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3230 	struct spdk_nvmf_rdma_poller		*poller;
3231 	struct spdk_nvmf_rdma_device		*device;
3232 	struct spdk_rdma_srq_init_attr		srq_init_attr;
3233 	struct spdk_nvmf_rdma_resource_opts	opts;
3234 	int					num_cqe;
3235 
3236 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3237 
3238 	rgroup = calloc(1, sizeof(*rgroup));
3239 	if (!rgroup) {
3240 		return NULL;
3241 	}
3242 
3243 	TAILQ_INIT(&rgroup->pollers);
3244 
3245 	pthread_mutex_lock(&rtransport->lock);
3246 	TAILQ_FOREACH(device, &rtransport->devices, link) {
3247 		poller = calloc(1, sizeof(*poller));
3248 		if (!poller) {
3249 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
3250 			nvmf_rdma_poll_group_destroy(&rgroup->group);
3251 			pthread_mutex_unlock(&rtransport->lock);
3252 			return NULL;
3253 		}
3254 
3255 		poller->device = device;
3256 		poller->group = rgroup;
3257 
3258 		TAILQ_INIT(&poller->qpairs);
3259 		STAILQ_INIT(&poller->qpairs_pending_send);
3260 		STAILQ_INIT(&poller->qpairs_pending_recv);
3261 
3262 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
3263 		if (rtransport->rdma_opts.no_srq == false && device->num_srq < device->attr.max_srq) {
3264 			poller->max_srq_depth = rtransport->rdma_opts.max_srq_depth;
3265 
3266 			device->num_srq++;
3267 			memset(&srq_init_attr, 0, sizeof(srq_init_attr));
3268 			srq_init_attr.pd = device->pd;
3269 			srq_init_attr.stats = &poller->stat.qp_stats.recv;
3270 			srq_init_attr.srq_init_attr.attr.max_wr = poller->max_srq_depth;
3271 			srq_init_attr.srq_init_attr.attr.max_sge = spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
3272 			poller->srq = spdk_rdma_srq_create(&srq_init_attr);
3273 			if (!poller->srq) {
3274 				SPDK_ERRLOG("Unable to create shared receive queue, errno %d\n", errno);
3275 				nvmf_rdma_poll_group_destroy(&rgroup->group);
3276 				pthread_mutex_unlock(&rtransport->lock);
3277 				return NULL;
3278 			}
3279 
3280 			opts.qp = poller->srq;
3281 			opts.pd = device->pd;
3282 			opts.qpair = NULL;
3283 			opts.shared = true;
3284 			opts.max_queue_depth = poller->max_srq_depth;
3285 			opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
3286 
3287 			poller->resources = nvmf_rdma_resources_create(&opts);
3288 			if (!poller->resources) {
3289 				SPDK_ERRLOG("Unable to allocate resources for shared receive queue.\n");
3290 				nvmf_rdma_poll_group_destroy(&rgroup->group);
3291 				pthread_mutex_unlock(&rtransport->lock);
3292 				return NULL;
3293 			}
3294 		}
3295 
3296 		/*
3297 		 * When using an srq, we can limit the completion queue at startup.
3298 		 * The following formula represents the calculation:
3299 		 * num_cqe = num_recv + num_data_wr + num_send_wr.
3300 		 * where num_recv=num_data_wr=and num_send_wr=poller->max_srq_depth
3301 		 */
3302 		if (poller->srq) {
3303 			num_cqe = poller->max_srq_depth * 3;
3304 		} else {
3305 			num_cqe = rtransport->rdma_opts.num_cqe;
3306 		}
3307 
3308 		poller->cq = ibv_create_cq(device->context, num_cqe, poller, NULL, 0);
3309 		if (!poller->cq) {
3310 			SPDK_ERRLOG("Unable to create completion queue\n");
3311 			nvmf_rdma_poll_group_destroy(&rgroup->group);
3312 			pthread_mutex_unlock(&rtransport->lock);
3313 			return NULL;
3314 		}
3315 		poller->num_cqe = num_cqe;
3316 	}
3317 
3318 	TAILQ_INSERT_TAIL(&rtransport->poll_groups, rgroup, link);
3319 	if (rtransport->conn_sched.next_admin_pg == NULL) {
3320 		rtransport->conn_sched.next_admin_pg = rgroup;
3321 		rtransport->conn_sched.next_io_pg = rgroup;
3322 	}
3323 
3324 	pthread_mutex_unlock(&rtransport->lock);
3325 	return &rgroup->group;
3326 }
3327 
3328 static struct spdk_nvmf_transport_poll_group *
3329 nvmf_rdma_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
3330 {
3331 	struct spdk_nvmf_rdma_transport *rtransport;
3332 	struct spdk_nvmf_rdma_poll_group **pg;
3333 	struct spdk_nvmf_transport_poll_group *result;
3334 
3335 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
3336 
3337 	pthread_mutex_lock(&rtransport->lock);
3338 
3339 	if (TAILQ_EMPTY(&rtransport->poll_groups)) {
3340 		pthread_mutex_unlock(&rtransport->lock);
3341 		return NULL;
3342 	}
3343 
3344 	if (qpair->qid == 0) {
3345 		pg = &rtransport->conn_sched.next_admin_pg;
3346 	} else {
3347 		pg = &rtransport->conn_sched.next_io_pg;
3348 	}
3349 
3350 	assert(*pg != NULL);
3351 
3352 	result = &(*pg)->group;
3353 
3354 	*pg = TAILQ_NEXT(*pg, link);
3355 	if (*pg == NULL) {
3356 		*pg = TAILQ_FIRST(&rtransport->poll_groups);
3357 	}
3358 
3359 	pthread_mutex_unlock(&rtransport->lock);
3360 
3361 	return result;
3362 }
3363 
3364 static void
3365 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
3366 {
3367 	struct spdk_nvmf_rdma_poll_group	*rgroup, *next_rgroup;
3368 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
3369 	struct spdk_nvmf_rdma_qpair		*qpair, *tmp_qpair;
3370 	struct spdk_nvmf_rdma_transport		*rtransport;
3371 
3372 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3373 	if (!rgroup) {
3374 		return;
3375 	}
3376 
3377 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
3378 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
3379 
3380 		TAILQ_FOREACH_SAFE(qpair, &poller->qpairs, link, tmp_qpair) {
3381 			nvmf_rdma_qpair_destroy(qpair);
3382 		}
3383 
3384 		if (poller->srq) {
3385 			if (poller->resources) {
3386 				nvmf_rdma_resources_destroy(poller->resources);
3387 			}
3388 			spdk_rdma_srq_destroy(poller->srq);
3389 			SPDK_DEBUGLOG(rdma, "Destroyed RDMA shared queue %p\n", poller->srq);
3390 		}
3391 
3392 		if (poller->cq) {
3393 			ibv_destroy_cq(poller->cq);
3394 		}
3395 
3396 		free(poller);
3397 	}
3398 
3399 	if (rgroup->group.transport == NULL) {
3400 		/* Transport can be NULL when nvmf_rdma_poll_group_create()
3401 		 * calls this function directly in a failure path. */
3402 		free(rgroup);
3403 		return;
3404 	}
3405 
3406 	rtransport = SPDK_CONTAINEROF(rgroup->group.transport, struct spdk_nvmf_rdma_transport, transport);
3407 
3408 	pthread_mutex_lock(&rtransport->lock);
3409 	next_rgroup = TAILQ_NEXT(rgroup, link);
3410 	TAILQ_REMOVE(&rtransport->poll_groups, rgroup, link);
3411 	if (next_rgroup == NULL) {
3412 		next_rgroup = TAILQ_FIRST(&rtransport->poll_groups);
3413 	}
3414 	if (rtransport->conn_sched.next_admin_pg == rgroup) {
3415 		rtransport->conn_sched.next_admin_pg = next_rgroup;
3416 	}
3417 	if (rtransport->conn_sched.next_io_pg == rgroup) {
3418 		rtransport->conn_sched.next_io_pg = next_rgroup;
3419 	}
3420 	pthread_mutex_unlock(&rtransport->lock);
3421 
3422 	free(rgroup);
3423 }
3424 
3425 static void
3426 nvmf_rdma_qpair_reject_connection(struct spdk_nvmf_rdma_qpair *rqpair)
3427 {
3428 	if (rqpair->cm_id != NULL) {
3429 		nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
3430 	}
3431 }
3432 
3433 static int
3434 nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
3435 			 struct spdk_nvmf_qpair *qpair)
3436 {
3437 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3438 	struct spdk_nvmf_rdma_qpair		*rqpair;
3439 	struct spdk_nvmf_rdma_device		*device;
3440 	struct spdk_nvmf_rdma_poller		*poller;
3441 	int					rc;
3442 
3443 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3444 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3445 
3446 	device = rqpair->device;
3447 
3448 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
3449 		if (poller->device == device) {
3450 			break;
3451 		}
3452 	}
3453 
3454 	if (!poller) {
3455 		SPDK_ERRLOG("No poller found for device.\n");
3456 		return -1;
3457 	}
3458 
3459 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
3460 	rqpair->poller = poller;
3461 	rqpair->srq = rqpair->poller->srq;
3462 
3463 	rc = nvmf_rdma_qpair_initialize(qpair);
3464 	if (rc < 0) {
3465 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
3466 		return -1;
3467 	}
3468 
3469 	rc = nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
3470 	if (rc) {
3471 		/* Try to reject, but we probably can't */
3472 		nvmf_rdma_qpair_reject_connection(rqpair);
3473 		return -1;
3474 	}
3475 
3476 	nvmf_rdma_update_ibv_state(rqpair);
3477 
3478 	return 0;
3479 }
3480 
3481 static int
3482 nvmf_rdma_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
3483 			    struct spdk_nvmf_qpair *qpair)
3484 {
3485 	struct spdk_nvmf_rdma_qpair		*rqpair;
3486 
3487 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3488 	assert(group->transport->tgt != NULL);
3489 
3490 	rqpair->destruct_channel = spdk_get_io_channel(group->transport->tgt);
3491 
3492 	if (!rqpair->destruct_channel) {
3493 		SPDK_WARNLOG("failed to get io_channel, qpair %p\n", qpair);
3494 		return 0;
3495 	}
3496 
3497 	/* Sanity check that we get io_channel on the correct thread */
3498 	if (qpair->group) {
3499 		assert(qpair->group->thread == spdk_io_channel_get_thread(rqpair->destruct_channel));
3500 	}
3501 
3502 	return 0;
3503 }
3504 
3505 static int
3506 nvmf_rdma_request_free(struct spdk_nvmf_request *req)
3507 {
3508 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
3509 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3510 			struct spdk_nvmf_rdma_transport, transport);
3511 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3512 					      struct spdk_nvmf_rdma_qpair, qpair);
3513 
3514 	/*
3515 	 * AER requests are freed when a qpair is destroyed. The recv corresponding to that request
3516 	 * needs to be returned to the shared receive queue or the poll group will eventually be
3517 	 * starved of RECV structures.
3518 	 */
3519 	if (rqpair->srq && rdma_req->recv) {
3520 		int rc;
3521 		struct ibv_recv_wr *bad_recv_wr;
3522 
3523 		spdk_rdma_srq_queue_recv_wrs(rqpair->srq, &rdma_req->recv->wr);
3524 		rc = spdk_rdma_srq_flush_recv_wrs(rqpair->srq, &bad_recv_wr);
3525 		if (rc) {
3526 			SPDK_ERRLOG("Unable to re-post rx descriptor\n");
3527 		}
3528 	}
3529 
3530 	_nvmf_rdma_request_free(rdma_req, rtransport);
3531 	return 0;
3532 }
3533 
3534 static int
3535 nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
3536 {
3537 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3538 			struct spdk_nvmf_rdma_transport, transport);
3539 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
3540 			struct spdk_nvmf_rdma_request, req);
3541 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3542 			struct spdk_nvmf_rdma_qpair, qpair);
3543 
3544 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3545 		/* The connection is alive, so process the request as normal */
3546 		rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
3547 	} else {
3548 		/* The connection is dead. Move the request directly to the completed state. */
3549 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3550 	}
3551 
3552 	nvmf_rdma_request_process(rtransport, rdma_req);
3553 
3554 	return 0;
3555 }
3556 
3557 static void
3558 nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair,
3559 		      spdk_nvmf_transport_qpair_fini_cb cb_fn, void *cb_arg)
3560 {
3561 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3562 
3563 	rqpair->to_close = true;
3564 
3565 	/* This happens only when the qpair is disconnected before
3566 	 * it is added to the poll group. Since there is no poll group,
3567 	 * the RDMA qp has not been initialized yet and the RDMA CM
3568 	 * event has not yet been acknowledged, so we need to reject it.
3569 	 */
3570 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
3571 		nvmf_rdma_qpair_reject_connection(rqpair);
3572 		nvmf_rdma_qpair_destroy(rqpair);
3573 		return;
3574 	}
3575 
3576 	if (rqpair->rdma_qp) {
3577 		spdk_rdma_qp_disconnect(rqpair->rdma_qp);
3578 	}
3579 
3580 	nvmf_rdma_destroy_drained_qpair(rqpair);
3581 
3582 	if (cb_fn) {
3583 		cb_fn(cb_arg);
3584 	}
3585 }
3586 
3587 static struct spdk_nvmf_rdma_qpair *
3588 get_rdma_qpair_from_wc(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_wc *wc)
3589 {
3590 	struct spdk_nvmf_rdma_qpair *rqpair;
3591 	/* @todo: improve QP search */
3592 	TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
3593 		if (wc->qp_num == rqpair->rdma_qp->qp->qp_num) {
3594 			return rqpair;
3595 		}
3596 	}
3597 	SPDK_ERRLOG("Didn't find QP with qp_num %u\n", wc->qp_num);
3598 	return NULL;
3599 }
3600 
3601 #ifdef DEBUG
3602 static int
3603 nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
3604 {
3605 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
3606 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
3607 }
3608 #endif
3609 
3610 static void
3611 _poller_reset_failed_recvs(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_recv_wr *bad_recv_wr,
3612 			   int rc)
3613 {
3614 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3615 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3616 
3617 	SPDK_ERRLOG("Failed to post a recv for the poller %p with errno %d\n", rpoller, -rc);
3618 	while (bad_recv_wr != NULL) {
3619 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_recv_wr->wr_id;
3620 		rdma_recv = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3621 
3622 		rdma_recv->qpair->current_recv_depth++;
3623 		bad_recv_wr = bad_recv_wr->next;
3624 		SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rdma_recv->qpair, -rc);
3625 		spdk_nvmf_qpair_disconnect(&rdma_recv->qpair->qpair, NULL, NULL);
3626 	}
3627 }
3628 
3629 static void
3630 _qp_reset_failed_recvs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *bad_recv_wr, int rc)
3631 {
3632 	SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rqpair, -rc);
3633 	while (bad_recv_wr != NULL) {
3634 		bad_recv_wr = bad_recv_wr->next;
3635 		rqpair->current_recv_depth++;
3636 	}
3637 	spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3638 }
3639 
3640 static void
3641 _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
3642 		     struct spdk_nvmf_rdma_poller *rpoller)
3643 {
3644 	struct spdk_nvmf_rdma_qpair	*rqpair;
3645 	struct ibv_recv_wr		*bad_recv_wr;
3646 	int				rc;
3647 
3648 	if (rpoller->srq) {
3649 		rc = spdk_rdma_srq_flush_recv_wrs(rpoller->srq, &bad_recv_wr);
3650 		if (rc) {
3651 			_poller_reset_failed_recvs(rpoller, bad_recv_wr, rc);
3652 		}
3653 	} else {
3654 		while (!STAILQ_EMPTY(&rpoller->qpairs_pending_recv)) {
3655 			rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_recv);
3656 			rc = spdk_rdma_qp_flush_recv_wrs(rqpair->rdma_qp, &bad_recv_wr);
3657 			if (rc) {
3658 				_qp_reset_failed_recvs(rqpair, bad_recv_wr, rc);
3659 			}
3660 			STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_recv, recv_link);
3661 		}
3662 	}
3663 }
3664 
3665 static void
3666 _qp_reset_failed_sends(struct spdk_nvmf_rdma_transport *rtransport,
3667 		       struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_send_wr *bad_wr, int rc)
3668 {
3669 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3670 	struct spdk_nvmf_rdma_request	*prev_rdma_req = NULL, *cur_rdma_req = NULL;
3671 
3672 	SPDK_ERRLOG("Failed to post a send for the qpair %p with errno %d\n", rqpair, -rc);
3673 	for (; bad_wr != NULL; bad_wr = bad_wr->next) {
3674 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_wr->wr_id;
3675 		assert(rqpair->current_send_depth > 0);
3676 		rqpair->current_send_depth--;
3677 		switch (bad_rdma_wr->type) {
3678 		case RDMA_WR_TYPE_DATA:
3679 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3680 			if (bad_wr->opcode == IBV_WR_RDMA_READ) {
3681 				assert(rqpair->current_read_depth > 0);
3682 				rqpair->current_read_depth--;
3683 			}
3684 			break;
3685 		case RDMA_WR_TYPE_SEND:
3686 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3687 			break;
3688 		default:
3689 			SPDK_ERRLOG("Found a RECV in the list of pending SEND requests for qpair %p\n", rqpair);
3690 			prev_rdma_req = cur_rdma_req;
3691 			continue;
3692 		}
3693 
3694 		if (prev_rdma_req == cur_rdma_req) {
3695 			/* this request was handled by an earlier wr. i.e. we were performing an nvme read. */
3696 			/* We only have to check against prev_wr since each requests wrs are contiguous in this list. */
3697 			continue;
3698 		}
3699 
3700 		switch (cur_rdma_req->state) {
3701 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
3702 			cur_rdma_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
3703 			cur_rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
3704 			break;
3705 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
3706 		case RDMA_REQUEST_STATE_COMPLETING:
3707 			cur_rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3708 			break;
3709 		default:
3710 			SPDK_ERRLOG("Found a request in a bad state %d when draining pending SEND requests for qpair %p\n",
3711 				    cur_rdma_req->state, rqpair);
3712 			continue;
3713 		}
3714 
3715 		nvmf_rdma_request_process(rtransport, cur_rdma_req);
3716 		prev_rdma_req = cur_rdma_req;
3717 	}
3718 
3719 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3720 		/* Disconnect the connection. */
3721 		spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3722 	}
3723 
3724 }
3725 
3726 static void
3727 _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
3728 		     struct spdk_nvmf_rdma_poller *rpoller)
3729 {
3730 	struct spdk_nvmf_rdma_qpair	*rqpair;
3731 	struct ibv_send_wr		*bad_wr = NULL;
3732 	int				rc;
3733 
3734 	while (!STAILQ_EMPTY(&rpoller->qpairs_pending_send)) {
3735 		rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_send);
3736 		rc = spdk_rdma_qp_flush_send_wrs(rqpair->rdma_qp, &bad_wr);
3737 
3738 		/* bad wr always points to the first wr that failed. */
3739 		if (rc) {
3740 			_qp_reset_failed_sends(rtransport, rqpair, bad_wr, rc);
3741 		}
3742 		STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_send, send_link);
3743 	}
3744 }
3745 
3746 static const char *
3747 nvmf_rdma_wr_type_str(enum spdk_nvmf_rdma_wr_type wr_type)
3748 {
3749 	switch (wr_type) {
3750 	case RDMA_WR_TYPE_RECV:
3751 		return "RECV";
3752 	case RDMA_WR_TYPE_SEND:
3753 		return "SEND";
3754 	case RDMA_WR_TYPE_DATA:
3755 		return "DATA";
3756 	default:
3757 		SPDK_ERRLOG("Unknown WR type %d\n", wr_type);
3758 		SPDK_UNREACHABLE();
3759 	}
3760 }
3761 
3762 static inline void
3763 nvmf_rdma_log_wc_status(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_wc *wc)
3764 {
3765 	enum spdk_nvmf_rdma_wr_type wr_type = ((struct spdk_nvmf_rdma_wr *)wc->wr_id)->type;
3766 
3767 	if (wc->status == IBV_WC_WR_FLUSH_ERR) {
3768 		/* If qpair is in ERR state, we will receive completions for all posted and not completed
3769 		 * Work Requests with IBV_WC_WR_FLUSH_ERR status. Don't log an error in that case */
3770 		SPDK_DEBUGLOG(rdma,
3771 			      "Error on CQ %p, (qp state %d ibv_state %d) request 0x%lu, type %s, status: (%d): %s\n",
3772 			      rqpair->poller->cq, rqpair->qpair.state, rqpair->ibv_state, wc->wr_id,
3773 			      nvmf_rdma_wr_type_str(wr_type), wc->status, ibv_wc_status_str(wc->status));
3774 	} else {
3775 		SPDK_ERRLOG("Error on CQ %p, (qp state %d ibv_state %d) request 0x%lu, type %s, status: (%d): %s\n",
3776 			    rqpair->poller->cq, rqpair->qpair.state, rqpair->ibv_state, wc->wr_id,
3777 			    nvmf_rdma_wr_type_str(wr_type), wc->status, ibv_wc_status_str(wc->status));
3778 	}
3779 }
3780 
3781 static int
3782 nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
3783 		      struct spdk_nvmf_rdma_poller *rpoller)
3784 {
3785 	struct ibv_wc wc[32];
3786 	struct spdk_nvmf_rdma_wr	*rdma_wr;
3787 	struct spdk_nvmf_rdma_request	*rdma_req;
3788 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3789 	struct spdk_nvmf_rdma_qpair	*rqpair;
3790 	int reaped, i;
3791 	int count = 0;
3792 	bool error = false;
3793 	uint64_t poll_tsc = spdk_get_ticks();
3794 
3795 	/* Poll for completing operations. */
3796 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
3797 	if (reaped < 0) {
3798 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
3799 			    errno, spdk_strerror(errno));
3800 		return -1;
3801 	} else if (reaped == 0) {
3802 		rpoller->stat.idle_polls++;
3803 	}
3804 
3805 	rpoller->stat.polls++;
3806 	rpoller->stat.completions += reaped;
3807 
3808 	for (i = 0; i < reaped; i++) {
3809 
3810 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
3811 
3812 		switch (rdma_wr->type) {
3813 		case RDMA_WR_TYPE_SEND:
3814 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3815 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3816 
3817 			if (!wc[i].status) {
3818 				count++;
3819 				assert(wc[i].opcode == IBV_WC_SEND);
3820 				assert(nvmf_rdma_req_is_completing(rdma_req));
3821 			}
3822 
3823 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3824 			/* RDMA_WRITE operation completed. +1 since it was chained with rsp WR */
3825 			rqpair->current_send_depth -= rdma_req->num_outstanding_data_wr + 1;
3826 			rdma_req->num_outstanding_data_wr = 0;
3827 
3828 			nvmf_rdma_request_process(rtransport, rdma_req);
3829 			break;
3830 		case RDMA_WR_TYPE_RECV:
3831 			/* rdma_recv->qpair will be invalid if using an SRQ.  In that case we have to get the qpair from the wc. */
3832 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3833 			if (rpoller->srq != NULL) {
3834 				rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
3835 				/* It is possible that there are still some completions for destroyed QP
3836 				 * associated with SRQ. We just ignore these late completions and re-post
3837 				 * receive WRs back to SRQ.
3838 				 */
3839 				if (spdk_unlikely(NULL == rdma_recv->qpair)) {
3840 					struct ibv_recv_wr *bad_wr;
3841 					int rc;
3842 
3843 					rdma_recv->wr.next = NULL;
3844 					spdk_rdma_srq_queue_recv_wrs(rpoller->srq, &rdma_recv->wr);
3845 					rc = spdk_rdma_srq_flush_recv_wrs(rpoller->srq, &bad_wr);
3846 					if (rc) {
3847 						SPDK_ERRLOG("Failed to re-post recv WR to SRQ, err %d\n", rc);
3848 					}
3849 					continue;
3850 				}
3851 			}
3852 			rqpair = rdma_recv->qpair;
3853 
3854 			assert(rqpair != NULL);
3855 			if (!wc[i].status) {
3856 				assert(wc[i].opcode == IBV_WC_RECV);
3857 				if (rqpair->current_recv_depth >= rqpair->max_queue_depth) {
3858 					spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3859 					break;
3860 				}
3861 			}
3862 
3863 			rdma_recv->wr.next = NULL;
3864 			rqpair->current_recv_depth++;
3865 			rdma_recv->receive_tsc = poll_tsc;
3866 			rpoller->stat.requests++;
3867 			STAILQ_INSERT_TAIL(&rqpair->resources->incoming_queue, rdma_recv, link);
3868 			break;
3869 		case RDMA_WR_TYPE_DATA:
3870 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3871 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3872 
3873 			assert(rdma_req->num_outstanding_data_wr > 0);
3874 
3875 			rqpair->current_send_depth--;
3876 			rdma_req->num_outstanding_data_wr--;
3877 			if (!wc[i].status) {
3878 				assert(wc[i].opcode == IBV_WC_RDMA_READ);
3879 				rqpair->current_read_depth--;
3880 				/* wait for all outstanding reads associated with the same rdma_req to complete before proceeding. */
3881 				if (rdma_req->num_outstanding_data_wr == 0) {
3882 					rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
3883 					nvmf_rdma_request_process(rtransport, rdma_req);
3884 				}
3885 			} else {
3886 				/* If the data transfer fails still force the queue into the error state,
3887 				 * if we were performing an RDMA_READ, we need to force the request into a
3888 				 * completed state since it wasn't linked to a send. However, in the RDMA_WRITE
3889 				 * case, we should wait for the SEND to complete. */
3890 				if (rdma_req->data.wr.opcode == IBV_WR_RDMA_READ) {
3891 					rqpair->current_read_depth--;
3892 					if (rdma_req->num_outstanding_data_wr == 0) {
3893 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3894 					}
3895 				}
3896 			}
3897 			break;
3898 		default:
3899 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
3900 			continue;
3901 		}
3902 
3903 		/* Handle error conditions */
3904 		if (wc[i].status) {
3905 			nvmf_rdma_update_ibv_state(rqpair);
3906 			nvmf_rdma_log_wc_status(rqpair, &wc[i]);
3907 
3908 			error = true;
3909 
3910 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3911 				/* Disconnect the connection. */
3912 				spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3913 			} else {
3914 				nvmf_rdma_destroy_drained_qpair(rqpair);
3915 			}
3916 			continue;
3917 		}
3918 
3919 		nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3920 
3921 		if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
3922 			nvmf_rdma_destroy_drained_qpair(rqpair);
3923 		}
3924 	}
3925 
3926 	if (error == true) {
3927 		return -1;
3928 	}
3929 
3930 	/* submit outstanding work requests. */
3931 	_poller_submit_recvs(rtransport, rpoller);
3932 	_poller_submit_sends(rtransport, rpoller);
3933 
3934 	return count;
3935 }
3936 
3937 static int
3938 nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3939 {
3940 	struct spdk_nvmf_rdma_transport *rtransport;
3941 	struct spdk_nvmf_rdma_poll_group *rgroup;
3942 	struct spdk_nvmf_rdma_poller	*rpoller;
3943 	int				count, rc;
3944 
3945 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
3946 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3947 
3948 	count = 0;
3949 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3950 		rc = nvmf_rdma_poller_poll(rtransport, rpoller);
3951 		if (rc < 0) {
3952 			return rc;
3953 		}
3954 		count += rc;
3955 	}
3956 
3957 	return count;
3958 }
3959 
3960 static int
3961 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
3962 			  struct spdk_nvme_transport_id *trid,
3963 			  bool peer)
3964 {
3965 	struct sockaddr *saddr;
3966 	uint16_t port;
3967 
3968 	spdk_nvme_trid_populate_transport(trid, SPDK_NVME_TRANSPORT_RDMA);
3969 
3970 	if (peer) {
3971 		saddr = rdma_get_peer_addr(id);
3972 	} else {
3973 		saddr = rdma_get_local_addr(id);
3974 	}
3975 	switch (saddr->sa_family) {
3976 	case AF_INET: {
3977 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
3978 
3979 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3980 		inet_ntop(AF_INET, &saddr_in->sin_addr,
3981 			  trid->traddr, sizeof(trid->traddr));
3982 		if (peer) {
3983 			port = ntohs(rdma_get_dst_port(id));
3984 		} else {
3985 			port = ntohs(rdma_get_src_port(id));
3986 		}
3987 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3988 		break;
3989 	}
3990 	case AF_INET6: {
3991 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
3992 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3993 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
3994 			  trid->traddr, sizeof(trid->traddr));
3995 		if (peer) {
3996 			port = ntohs(rdma_get_dst_port(id));
3997 		} else {
3998 			port = ntohs(rdma_get_src_port(id));
3999 		}
4000 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
4001 		break;
4002 	}
4003 	default:
4004 		return -1;
4005 
4006 	}
4007 
4008 	return 0;
4009 }
4010 
4011 static int
4012 nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
4013 			      struct spdk_nvme_transport_id *trid)
4014 {
4015 	struct spdk_nvmf_rdma_qpair	*rqpair;
4016 
4017 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4018 
4019 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
4020 }
4021 
4022 static int
4023 nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
4024 			       struct spdk_nvme_transport_id *trid)
4025 {
4026 	struct spdk_nvmf_rdma_qpair	*rqpair;
4027 
4028 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4029 
4030 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
4031 }
4032 
4033 static int
4034 nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
4035 				struct spdk_nvme_transport_id *trid)
4036 {
4037 	struct spdk_nvmf_rdma_qpair	*rqpair;
4038 
4039 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4040 
4041 	return nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
4042 }
4043 
4044 void
4045 spdk_nvmf_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
4046 {
4047 	g_nvmf_hooks = *hooks;
4048 }
4049 
4050 static void
4051 nvmf_rdma_request_set_abort_status(struct spdk_nvmf_request *req,
4052 				   struct spdk_nvmf_rdma_request *rdma_req_to_abort)
4053 {
4054 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
4055 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_BY_REQUEST;
4056 
4057 	rdma_req_to_abort->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
4058 
4059 	req->rsp->nvme_cpl.cdw0 &= ~1U;	/* Command was successfully aborted. */
4060 }
4061 
4062 static int
4063 _nvmf_rdma_qpair_abort_request(void *ctx)
4064 {
4065 	struct spdk_nvmf_request *req = ctx;
4066 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = SPDK_CONTAINEROF(
4067 				req->req_to_abort, struct spdk_nvmf_rdma_request, req);
4068 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(req->req_to_abort->qpair,
4069 					      struct spdk_nvmf_rdma_qpair, qpair);
4070 	int rc;
4071 
4072 	spdk_poller_unregister(&req->poller);
4073 
4074 	switch (rdma_req_to_abort->state) {
4075 	case RDMA_REQUEST_STATE_EXECUTING:
4076 		rc = nvmf_ctrlr_abort_request(req);
4077 		if (rc == SPDK_NVMF_REQUEST_EXEC_STATUS_ASYNCHRONOUS) {
4078 			return SPDK_POLLER_BUSY;
4079 		}
4080 		break;
4081 
4082 	case RDMA_REQUEST_STATE_NEED_BUFFER:
4083 		STAILQ_REMOVE(&rqpair->poller->group->group.pending_buf_queue,
4084 			      &rdma_req_to_abort->req, spdk_nvmf_request, buf_link);
4085 
4086 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4087 		break;
4088 
4089 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
4090 		STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req_to_abort,
4091 			      spdk_nvmf_rdma_request, state_link);
4092 
4093 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4094 		break;
4095 
4096 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
4097 		STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req_to_abort,
4098 			      spdk_nvmf_rdma_request, state_link);
4099 
4100 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4101 		break;
4102 
4103 	case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
4104 		if (spdk_get_ticks() < req->timeout_tsc) {
4105 			req->poller = SPDK_POLLER_REGISTER(_nvmf_rdma_qpair_abort_request, req, 0);
4106 			return SPDK_POLLER_BUSY;
4107 		}
4108 		break;
4109 
4110 	default:
4111 		break;
4112 	}
4113 
4114 	spdk_nvmf_request_complete(req);
4115 	return SPDK_POLLER_BUSY;
4116 }
4117 
4118 static void
4119 nvmf_rdma_qpair_abort_request(struct spdk_nvmf_qpair *qpair,
4120 			      struct spdk_nvmf_request *req)
4121 {
4122 	struct spdk_nvmf_rdma_qpair *rqpair;
4123 	struct spdk_nvmf_rdma_transport *rtransport;
4124 	struct spdk_nvmf_transport *transport;
4125 	uint16_t cid;
4126 	uint32_t i, max_req_count;
4127 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = NULL, *rdma_req;
4128 
4129 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4130 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
4131 	transport = &rtransport->transport;
4132 
4133 	cid = req->cmd->nvme_cmd.cdw10_bits.abort.cid;
4134 	max_req_count = rqpair->srq == NULL ? rqpair->max_queue_depth : rqpair->poller->max_srq_depth;
4135 
4136 	for (i = 0; i < max_req_count; i++) {
4137 		rdma_req = &rqpair->resources->reqs[i];
4138 		/* When SRQ == NULL, rqpair has its own requests and req.qpair pointer always points to the qpair
4139 		 * When SRQ != NULL all rqpairs share common requests and qpair pointer is assigned when we start to
4140 		 * process a request. So in both cases all requests which are not in FREE state have valid qpair ptr */
4141 		if (rdma_req->state != RDMA_REQUEST_STATE_FREE && rdma_req->req.cmd->nvme_cmd.cid == cid &&
4142 		    rdma_req->req.qpair == qpair) {
4143 			rdma_req_to_abort = rdma_req;
4144 			break;
4145 		}
4146 	}
4147 
4148 	if (rdma_req_to_abort == NULL) {
4149 		spdk_nvmf_request_complete(req);
4150 		return;
4151 	}
4152 
4153 	req->req_to_abort = &rdma_req_to_abort->req;
4154 	req->timeout_tsc = spdk_get_ticks() +
4155 			   transport->opts.abort_timeout_sec * spdk_get_ticks_hz();
4156 	req->poller = NULL;
4157 
4158 	_nvmf_rdma_qpair_abort_request(req);
4159 }
4160 
4161 static void
4162 nvmf_rdma_poll_group_dump_stat(struct spdk_nvmf_transport_poll_group *group,
4163 			       struct spdk_json_write_ctx *w)
4164 {
4165 	struct spdk_nvmf_rdma_poll_group *rgroup;
4166 	struct spdk_nvmf_rdma_poller *rpoller;
4167 
4168 	assert(w != NULL);
4169 
4170 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
4171 
4172 	spdk_json_write_named_uint64(w, "pending_data_buffer", rgroup->stat.pending_data_buffer);
4173 
4174 	spdk_json_write_named_array_begin(w, "devices");
4175 
4176 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4177 		spdk_json_write_object_begin(w);
4178 		spdk_json_write_named_string(w, "name",
4179 					     ibv_get_device_name(rpoller->device->context->device));
4180 		spdk_json_write_named_uint64(w, "polls",
4181 					     rpoller->stat.polls);
4182 		spdk_json_write_named_uint64(w, "idle_polls",
4183 					     rpoller->stat.idle_polls);
4184 		spdk_json_write_named_uint64(w, "completions",
4185 					     rpoller->stat.completions);
4186 		spdk_json_write_named_uint64(w, "requests",
4187 					     rpoller->stat.requests);
4188 		spdk_json_write_named_uint64(w, "request_latency",
4189 					     rpoller->stat.request_latency);
4190 		spdk_json_write_named_uint64(w, "pending_free_request",
4191 					     rpoller->stat.pending_free_request);
4192 		spdk_json_write_named_uint64(w, "pending_rdma_read",
4193 					     rpoller->stat.pending_rdma_read);
4194 		spdk_json_write_named_uint64(w, "pending_rdma_write",
4195 					     rpoller->stat.pending_rdma_write);
4196 		spdk_json_write_named_uint64(w, "total_send_wrs",
4197 					     rpoller->stat.qp_stats.send.num_submitted_wrs);
4198 		spdk_json_write_named_uint64(w, "send_doorbell_updates",
4199 					     rpoller->stat.qp_stats.send.doorbell_updates);
4200 		spdk_json_write_named_uint64(w, "total_recv_wrs",
4201 					     rpoller->stat.qp_stats.recv.num_submitted_wrs);
4202 		spdk_json_write_named_uint64(w, "recv_doorbell_updates",
4203 					     rpoller->stat.qp_stats.recv.doorbell_updates);
4204 		spdk_json_write_object_end(w);
4205 	}
4206 
4207 	spdk_json_write_array_end(w);
4208 }
4209 
4210 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
4211 	.name = "RDMA",
4212 	.type = SPDK_NVME_TRANSPORT_RDMA,
4213 	.opts_init = nvmf_rdma_opts_init,
4214 	.create = nvmf_rdma_create,
4215 	.dump_opts = nvmf_rdma_dump_opts,
4216 	.destroy = nvmf_rdma_destroy,
4217 
4218 	.listen = nvmf_rdma_listen,
4219 	.stop_listen = nvmf_rdma_stop_listen,
4220 	.accept = nvmf_rdma_accept,
4221 	.cdata_init = nvmf_rdma_cdata_init,
4222 
4223 	.listener_discover = nvmf_rdma_discover,
4224 
4225 	.poll_group_create = nvmf_rdma_poll_group_create,
4226 	.get_optimal_poll_group = nvmf_rdma_get_optimal_poll_group,
4227 	.poll_group_destroy = nvmf_rdma_poll_group_destroy,
4228 	.poll_group_add = nvmf_rdma_poll_group_add,
4229 	.poll_group_remove = nvmf_rdma_poll_group_remove,
4230 	.poll_group_poll = nvmf_rdma_poll_group_poll,
4231 
4232 	.req_free = nvmf_rdma_request_free,
4233 	.req_complete = nvmf_rdma_request_complete,
4234 
4235 	.qpair_fini = nvmf_rdma_close_qpair,
4236 	.qpair_get_peer_trid = nvmf_rdma_qpair_get_peer_trid,
4237 	.qpair_get_local_trid = nvmf_rdma_qpair_get_local_trid,
4238 	.qpair_get_listen_trid = nvmf_rdma_qpair_get_listen_trid,
4239 	.qpair_abort_request = nvmf_rdma_qpair_abort_request,
4240 
4241 	.poll_group_dump_stat = nvmf_rdma_poll_group_dump_stat,
4242 };
4243 
4244 SPDK_NVMF_TRANSPORT_REGISTER(rdma, &spdk_nvmf_transport_rdma);
4245 SPDK_LOG_REGISTER_COMPONENT(rdma)
4246