xref: /spdk/lib/nvmf/rdma.c (revision 12ab86e24d916615b84d6eeb6f741600c25c64ab)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2018 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 <infiniband/verbs.h>
37 #include <rdma/rdma_cma.h>
38 #include <rdma/rdma_verbs.h>
39 
40 #include "nvmf_internal.h"
41 #include "transport.h"
42 
43 #include "spdk/config.h"
44 #include "spdk/assert.h"
45 #include "spdk/thread.h"
46 #include "spdk/nvmf.h"
47 #include "spdk/nvmf_spec.h"
48 #include "spdk/string.h"
49 #include "spdk/trace.h"
50 #include "spdk/util.h"
51 
52 #include "spdk_internal/log.h"
53 
54 struct spdk_nvme_rdma_hooks g_nvmf_hooks = {};
55 
56 /*
57  RDMA Connection Resource Defaults
58  */
59 #define NVMF_DEFAULT_TX_SGE		SPDK_NVMF_MAX_SGL_ENTRIES
60 #define NVMF_DEFAULT_RSP_SGE		1
61 #define NVMF_DEFAULT_RX_SGE		2
62 
63 /* The RDMA completion queue size */
64 #define DEFAULT_NVMF_RDMA_CQ_SIZE	4096
65 #define MAX_WR_PER_QP(queue_depth)	(queue_depth * 3 + 2)
66 
67 /* Timeout for destroying defunct rqpairs */
68 #define NVMF_RDMA_QPAIR_DESTROY_TIMEOUT_US	4000000
69 
70 /* The maximum number of buffers per request */
71 #define NVMF_REQ_MAX_BUFFERS	(SPDK_NVMF_MAX_SGL_ENTRIES * 2)
72 
73 static int g_spdk_nvmf_ibv_query_mask =
74 	IBV_QP_STATE |
75 	IBV_QP_PKEY_INDEX |
76 	IBV_QP_PORT |
77 	IBV_QP_ACCESS_FLAGS |
78 	IBV_QP_AV |
79 	IBV_QP_PATH_MTU |
80 	IBV_QP_DEST_QPN |
81 	IBV_QP_RQ_PSN |
82 	IBV_QP_MAX_DEST_RD_ATOMIC |
83 	IBV_QP_MIN_RNR_TIMER |
84 	IBV_QP_SQ_PSN |
85 	IBV_QP_TIMEOUT |
86 	IBV_QP_RETRY_CNT |
87 	IBV_QP_RNR_RETRY |
88 	IBV_QP_MAX_QP_RD_ATOMIC;
89 
90 enum spdk_nvmf_rdma_request_state {
91 	/* The request is not currently in use */
92 	RDMA_REQUEST_STATE_FREE = 0,
93 
94 	/* Initial state when request first received */
95 	RDMA_REQUEST_STATE_NEW,
96 
97 	/* The request is queued until a data buffer is available. */
98 	RDMA_REQUEST_STATE_NEED_BUFFER,
99 
100 	/* The request is waiting on RDMA queue depth availability
101 	 * to transfer data from the host to the controller.
102 	 */
103 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
104 
105 	/* The request is currently transferring data from the host to the controller. */
106 	RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
107 
108 	/* The request is ready to execute at the block device */
109 	RDMA_REQUEST_STATE_READY_TO_EXECUTE,
110 
111 	/* The request is currently executing at the block device */
112 	RDMA_REQUEST_STATE_EXECUTING,
113 
114 	/* The request finished executing at the block device */
115 	RDMA_REQUEST_STATE_EXECUTED,
116 
117 	/* The request is waiting on RDMA queue depth availability
118 	 * to transfer data from the controller to the host.
119 	 */
120 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
121 
122 	/* The request is ready to send a completion */
123 	RDMA_REQUEST_STATE_READY_TO_COMPLETE,
124 
125 	/* The request is currently transferring data from the controller to the host. */
126 	RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
127 
128 	/* The request currently has an outstanding completion without an
129 	 * associated data transfer.
130 	 */
131 	RDMA_REQUEST_STATE_COMPLETING,
132 
133 	/* The request completed and can be marked free. */
134 	RDMA_REQUEST_STATE_COMPLETED,
135 
136 	/* Terminator */
137 	RDMA_REQUEST_NUM_STATES,
138 };
139 
140 #define OBJECT_NVMF_RDMA_IO				0x40
141 
142 #define TRACE_GROUP_NVMF_RDMA				0x4
143 #define TRACE_RDMA_REQUEST_STATE_NEW					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x0)
144 #define TRACE_RDMA_REQUEST_STATE_NEED_BUFFER				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x1)
145 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x2)
146 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x3)
147 #define TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x4)
148 #define TRACE_RDMA_REQUEST_STATE_EXECUTING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x5)
149 #define TRACE_RDMA_REQUEST_STATE_EXECUTED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x6)
150 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING		SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x7)
151 #define TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x8)
152 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x9)
153 #define TRACE_RDMA_REQUEST_STATE_COMPLETING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xA)
154 #define TRACE_RDMA_REQUEST_STATE_COMPLETED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xB)
155 #define TRACE_RDMA_QP_CREATE						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xC)
156 #define TRACE_RDMA_IBV_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xD)
157 #define TRACE_RDMA_CM_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xE)
158 #define TRACE_RDMA_QP_STATE_CHANGE					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xF)
159 #define TRACE_RDMA_QP_DISCONNECT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x10)
160 #define TRACE_RDMA_QP_DESTROY						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x11)
161 
162 SPDK_TRACE_REGISTER_FN(nvmf_trace, "nvmf_rdma", TRACE_GROUP_NVMF_RDMA)
163 {
164 	spdk_trace_register_object(OBJECT_NVMF_RDMA_IO, 'r');
165 	spdk_trace_register_description("RDMA_REQ_NEW", "",
166 					TRACE_RDMA_REQUEST_STATE_NEW,
167 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 1, 1, "cmid:   ");
168 	spdk_trace_register_description("RDMA_REQ_NEED_BUFFER", "",
169 					TRACE_RDMA_REQUEST_STATE_NEED_BUFFER,
170 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
171 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_C_TO_H", "",
172 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
173 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
174 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_H_TO_C", "",
175 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
176 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
177 	spdk_trace_register_description("RDMA_REQ_TX_H_TO_C", "",
178 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
179 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
180 	spdk_trace_register_description("RDMA_REQ_RDY_TO_EXECUTE", "",
181 					TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE,
182 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
183 	spdk_trace_register_description("RDMA_REQ_EXECUTING", "",
184 					TRACE_RDMA_REQUEST_STATE_EXECUTING,
185 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
186 	spdk_trace_register_description("RDMA_REQ_EXECUTED", "",
187 					TRACE_RDMA_REQUEST_STATE_EXECUTED,
188 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
189 	spdk_trace_register_description("RDMA_REQ_RDY_TO_COMPLETE", "",
190 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE,
191 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
192 	spdk_trace_register_description("RDMA_REQ_COMPLETING_CONTROLLER_TO_HOST", "",
193 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
194 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
195 	spdk_trace_register_description("RDMA_REQ_COMPLETING_INCAPSULE", "",
196 					TRACE_RDMA_REQUEST_STATE_COMPLETING,
197 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
198 	spdk_trace_register_description("RDMA_REQ_COMPLETED", "",
199 					TRACE_RDMA_REQUEST_STATE_COMPLETED,
200 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
201 
202 	spdk_trace_register_description("RDMA_QP_CREATE", "", TRACE_RDMA_QP_CREATE,
203 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
204 	spdk_trace_register_description("RDMA_IBV_ASYNC_EVENT", "", TRACE_RDMA_IBV_ASYNC_EVENT,
205 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
206 	spdk_trace_register_description("RDMA_CM_ASYNC_EVENT", "", TRACE_RDMA_CM_ASYNC_EVENT,
207 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
208 	spdk_trace_register_description("RDMA_QP_STATE_CHANGE", "", TRACE_RDMA_QP_STATE_CHANGE,
209 					OWNER_NONE, OBJECT_NONE, 0, 1, "state:  ");
210 	spdk_trace_register_description("RDMA_QP_DISCONNECT", "", TRACE_RDMA_QP_DISCONNECT,
211 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
212 	spdk_trace_register_description("RDMA_QP_DESTROY", "", TRACE_RDMA_QP_DESTROY,
213 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
214 }
215 
216 enum spdk_nvmf_rdma_wr_type {
217 	RDMA_WR_TYPE_RECV,
218 	RDMA_WR_TYPE_SEND,
219 	RDMA_WR_TYPE_DATA,
220 };
221 
222 struct spdk_nvmf_rdma_wr {
223 	enum spdk_nvmf_rdma_wr_type	type;
224 };
225 
226 /* This structure holds commands as they are received off the wire.
227  * It must be dynamically paired with a full request object
228  * (spdk_nvmf_rdma_request) to service a request. It is separate
229  * from the request because RDMA does not appear to order
230  * completions, so occasionally we'll get a new incoming
231  * command when there aren't any free request objects.
232  */
233 struct spdk_nvmf_rdma_recv {
234 	struct ibv_recv_wr			wr;
235 	struct ibv_sge				sgl[NVMF_DEFAULT_RX_SGE];
236 
237 	struct spdk_nvmf_rdma_qpair		*qpair;
238 
239 	/* In-capsule data buffer */
240 	uint8_t					*buf;
241 
242 	struct spdk_nvmf_rdma_wr		rdma_wr;
243 
244 	STAILQ_ENTRY(spdk_nvmf_rdma_recv)	link;
245 };
246 
247 struct spdk_nvmf_rdma_request_data {
248 	struct spdk_nvmf_rdma_wr	rdma_wr;
249 	struct ibv_send_wr		wr;
250 	struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
251 };
252 
253 struct spdk_nvmf_rdma_request {
254 	struct spdk_nvmf_request		req;
255 	bool					data_from_pool;
256 
257 	enum spdk_nvmf_rdma_request_state	state;
258 
259 	struct spdk_nvmf_rdma_recv		*recv;
260 
261 	struct {
262 		struct spdk_nvmf_rdma_wr	rdma_wr;
263 		struct	ibv_send_wr		wr;
264 		struct	ibv_sge			sgl[NVMF_DEFAULT_RSP_SGE];
265 	} rsp;
266 
267 	struct spdk_nvmf_rdma_request_data	data;
268 	void					*buffers[NVMF_REQ_MAX_BUFFERS];
269 
270 	uint32_t				num_outstanding_data_wr;
271 
272 	TAILQ_ENTRY(spdk_nvmf_rdma_request)	link;
273 	STAILQ_ENTRY(spdk_nvmf_rdma_request)	state_link;
274 };
275 
276 enum spdk_nvmf_rdma_qpair_disconnect_flags {
277 	RDMA_QP_DISCONNECTING		= 1,
278 	RDMA_QP_RECV_DRAINED		= 1 << 1,
279 	RDMA_QP_SEND_DRAINED		= 1 << 2
280 };
281 
282 struct spdk_nvmf_rdma_resource_opts {
283 	struct spdk_nvmf_rdma_qpair	*qpair;
284 	/* qp points either to an ibv_qp object or an ibv_srq object depending on the value of shared. */
285 	void				*qp;
286 	struct ibv_pd			*pd;
287 	uint32_t			max_queue_depth;
288 	uint32_t			in_capsule_data_size;
289 	bool				shared;
290 };
291 
292 struct spdk_nvmf_rdma_resources {
293 	/* Array of size "max_queue_depth" containing RDMA requests. */
294 	struct spdk_nvmf_rdma_request		*reqs;
295 
296 	/* Array of size "max_queue_depth" containing RDMA recvs. */
297 	struct spdk_nvmf_rdma_recv		*recvs;
298 
299 	/* Array of size "max_queue_depth" containing 64 byte capsules
300 	 * used for receive.
301 	 */
302 	union nvmf_h2c_msg			*cmds;
303 	struct ibv_mr				*cmds_mr;
304 
305 	/* Array of size "max_queue_depth" containing 16 byte completions
306 	 * to be sent back to the user.
307 	 */
308 	union nvmf_c2h_msg			*cpls;
309 	struct ibv_mr				*cpls_mr;
310 
311 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
312 	 * buffers to be used for in capsule data.
313 	 */
314 	void					*bufs;
315 	struct ibv_mr				*bufs_mr;
316 
317 	/* Receives that are waiting for a request object */
318 	STAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
319 
320 	/* Queue to track free requests */
321 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	free_queue;
322 };
323 
324 struct spdk_nvmf_rdma_qpair {
325 	struct spdk_nvmf_qpair			qpair;
326 
327 	struct spdk_nvmf_rdma_port		*port;
328 	struct spdk_nvmf_rdma_poller		*poller;
329 
330 	struct rdma_cm_id			*cm_id;
331 	struct ibv_srq				*srq;
332 	struct rdma_cm_id			*listen_id;
333 
334 	/* The maximum number of I/O outstanding on this connection at one time */
335 	uint16_t				max_queue_depth;
336 
337 	/* The maximum number of active RDMA READ and ATOMIC operations at one time */
338 	uint16_t				max_read_depth;
339 
340 	/* The maximum number of RDMA SEND operations at one time */
341 	uint32_t				max_send_depth;
342 
343 	/* The current number of outstanding WRs from this qpair's
344 	 * recv queue. Should not exceed device->attr.max_queue_depth.
345 	 */
346 	uint16_t				current_recv_depth;
347 
348 	/* The current number of active RDMA READ operations */
349 	uint16_t				current_read_depth;
350 
351 	/* The current number of posted WRs from this qpair's
352 	 * send queue. Should not exceed max_send_depth.
353 	 */
354 	uint32_t				current_send_depth;
355 
356 	/* The maximum number of SGEs per WR on the send queue */
357 	uint32_t				max_send_sge;
358 
359 	/* The maximum number of SGEs per WR on the recv queue */
360 	uint32_t				max_recv_sge;
361 
362 	struct spdk_nvmf_rdma_resources		*resources;
363 
364 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_read_queue;
365 
366 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_write_queue;
367 
368 	/* Number of requests not in the free state */
369 	uint32_t				qd;
370 
371 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	link;
372 
373 	/* IBV queue pair attributes: they are used to manage
374 	 * qp state and recover from errors.
375 	 */
376 	enum ibv_qp_state			ibv_state;
377 
378 	uint32_t				disconnect_flags;
379 
380 	/* Poller registered in case the qpair doesn't properly
381 	 * complete the qpair destruct process and becomes defunct.
382 	 */
383 
384 	struct spdk_poller			*destruct_poller;
385 
386 	/* There are several ways a disconnect can start on a qpair
387 	 * and they are not all mutually exclusive. It is important
388 	 * that we only initialize one of these paths.
389 	 */
390 	bool					disconnect_started;
391 	/* Lets us know that we have received the last_wqe event. */
392 	bool					last_wqe_reached;
393 };
394 
395 struct spdk_nvmf_rdma_poller {
396 	struct spdk_nvmf_rdma_device		*device;
397 	struct spdk_nvmf_rdma_poll_group	*group;
398 
399 	int					num_cqe;
400 	int					required_num_wr;
401 	struct ibv_cq				*cq;
402 
403 	/* The maximum number of I/O outstanding on the shared receive queue at one time */
404 	uint16_t				max_srq_depth;
405 
406 	/* Shared receive queue */
407 	struct ibv_srq				*srq;
408 
409 	struct spdk_nvmf_rdma_resources		*resources;
410 
411 	TAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs;
412 
413 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
414 };
415 
416 struct spdk_nvmf_rdma_poll_group {
417 	struct spdk_nvmf_transport_poll_group	group;
418 
419 	/* Requests that are waiting to obtain a data buffer */
420 	TAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_data_buf_queue;
421 
422 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)	pollers;
423 };
424 
425 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
426 struct spdk_nvmf_rdma_device {
427 	struct ibv_device_attr			attr;
428 	struct ibv_context			*context;
429 
430 	struct spdk_mem_map			*map;
431 	struct ibv_pd				*pd;
432 
433 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
434 };
435 
436 struct spdk_nvmf_rdma_port {
437 	struct spdk_nvme_transport_id		trid;
438 	struct rdma_cm_id			*id;
439 	struct spdk_nvmf_rdma_device		*device;
440 	uint32_t				ref;
441 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
442 };
443 
444 struct spdk_nvmf_rdma_transport {
445 	struct spdk_nvmf_transport	transport;
446 
447 	struct rdma_event_channel	*event_channel;
448 
449 	struct spdk_mempool		*data_wr_pool;
450 
451 	pthread_mutex_t			lock;
452 
453 	/* fields used to poll RDMA/IB events */
454 	nfds_t			npoll_fds;
455 	struct pollfd		*poll_fds;
456 
457 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
458 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
459 };
460 
461 static inline int
462 spdk_nvmf_rdma_check_ibv_state(enum ibv_qp_state state)
463 {
464 	switch (state) {
465 	case IBV_QPS_RESET:
466 	case IBV_QPS_INIT:
467 	case IBV_QPS_RTR:
468 	case IBV_QPS_RTS:
469 	case IBV_QPS_SQD:
470 	case IBV_QPS_SQE:
471 	case IBV_QPS_ERR:
472 		return 0;
473 	default:
474 		return -1;
475 	}
476 }
477 
478 static enum ibv_qp_state
479 spdk_nvmf_rdma_update_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair) {
480 	enum ibv_qp_state old_state, new_state;
481 	struct ibv_qp_attr qp_attr;
482 	struct ibv_qp_init_attr init_attr;
483 	int rc;
484 
485 	old_state = rqpair->ibv_state;
486 	rc = ibv_query_qp(rqpair->cm_id->qp, &qp_attr,
487 			  g_spdk_nvmf_ibv_query_mask, &init_attr);
488 
489 	if (rc)
490 	{
491 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
492 		return IBV_QPS_ERR + 1;
493 	}
494 
495 	new_state = qp_attr.qp_state;
496 	rqpair->ibv_state = new_state;
497 	qp_attr.ah_attr.port_num = qp_attr.port_num;
498 
499 	rc = spdk_nvmf_rdma_check_ibv_state(new_state);
500 	if (rc)
501 	{
502 		SPDK_ERRLOG("QP#%d: bad state updated: %u, maybe hardware issue\n", rqpair->qpair.qid, new_state);
503 		/*
504 		 * IBV_QPS_UNKNOWN undefined if lib version smaller than libibverbs-1.1.8
505 		 * IBV_QPS_UNKNOWN is the enum element after IBV_QPS_ERR
506 		 */
507 		return IBV_QPS_ERR + 1;
508 	}
509 
510 	if (old_state != new_state)
511 	{
512 		spdk_trace_record(TRACE_RDMA_QP_STATE_CHANGE, 0, 0,
513 				  (uintptr_t)rqpair->cm_id, new_state);
514 	}
515 	return new_state;
516 }
517 
518 static const char *str_ibv_qp_state[] = {
519 	"IBV_QPS_RESET",
520 	"IBV_QPS_INIT",
521 	"IBV_QPS_RTR",
522 	"IBV_QPS_RTS",
523 	"IBV_QPS_SQD",
524 	"IBV_QPS_SQE",
525 	"IBV_QPS_ERR",
526 	"IBV_QPS_UNKNOWN"
527 };
528 
529 static int
530 spdk_nvmf_rdma_set_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair,
531 			     enum ibv_qp_state new_state)
532 {
533 	struct ibv_qp_attr qp_attr;
534 	struct ibv_qp_init_attr init_attr;
535 	int rc;
536 	enum ibv_qp_state state;
537 	static int attr_mask_rc[] = {
538 		[IBV_QPS_RESET] = IBV_QP_STATE,
539 		[IBV_QPS_INIT] = (IBV_QP_STATE |
540 				  IBV_QP_PKEY_INDEX |
541 				  IBV_QP_PORT |
542 				  IBV_QP_ACCESS_FLAGS),
543 		[IBV_QPS_RTR] = (IBV_QP_STATE |
544 				 IBV_QP_AV |
545 				 IBV_QP_PATH_MTU |
546 				 IBV_QP_DEST_QPN |
547 				 IBV_QP_RQ_PSN |
548 				 IBV_QP_MAX_DEST_RD_ATOMIC |
549 				 IBV_QP_MIN_RNR_TIMER),
550 		[IBV_QPS_RTS] = (IBV_QP_STATE |
551 				 IBV_QP_SQ_PSN |
552 				 IBV_QP_TIMEOUT |
553 				 IBV_QP_RETRY_CNT |
554 				 IBV_QP_RNR_RETRY |
555 				 IBV_QP_MAX_QP_RD_ATOMIC),
556 		[IBV_QPS_SQD] = IBV_QP_STATE,
557 		[IBV_QPS_SQE] = IBV_QP_STATE,
558 		[IBV_QPS_ERR] = IBV_QP_STATE,
559 	};
560 
561 	rc = spdk_nvmf_rdma_check_ibv_state(new_state);
562 	if (rc) {
563 		SPDK_ERRLOG("QP#%d: bad state requested: %u\n",
564 			    rqpair->qpair.qid, new_state);
565 		return rc;
566 	}
567 
568 	rc = ibv_query_qp(rqpair->cm_id->qp, &qp_attr,
569 			  g_spdk_nvmf_ibv_query_mask, &init_attr);
570 
571 	if (rc) {
572 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
573 		assert(false);
574 	}
575 
576 	qp_attr.cur_qp_state = rqpair->ibv_state;
577 	qp_attr.qp_state = new_state;
578 
579 	rc = ibv_modify_qp(rqpair->cm_id->qp, &qp_attr,
580 			   attr_mask_rc[new_state]);
581 
582 	if (rc) {
583 		SPDK_ERRLOG("QP#%d: failed to set state to: %s, %d (%s)\n",
584 			    rqpair->qpair.qid, str_ibv_qp_state[new_state], errno, strerror(errno));
585 		return rc;
586 	}
587 
588 	state = spdk_nvmf_rdma_update_ibv_state(rqpair);
589 
590 	if (state != new_state) {
591 		SPDK_ERRLOG("QP#%d: expected state: %s, actual state: %s\n",
592 			    rqpair->qpair.qid, str_ibv_qp_state[new_state],
593 			    str_ibv_qp_state[state]);
594 		return -1;
595 	}
596 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "IBV QP#%u changed to: %s\n", rqpair->qpair.qid,
597 		      str_ibv_qp_state[state]);
598 	return 0;
599 }
600 
601 static void
602 nvmf_rdma_request_free_data(struct spdk_nvmf_rdma_request *rdma_req,
603 			    struct spdk_nvmf_rdma_transport *rtransport)
604 {
605 	struct spdk_nvmf_rdma_request_data	*current_data_wr = NULL, *next_data_wr = NULL;
606 	struct ibv_send_wr			*send_wr;
607 	int					i;
608 
609 	rdma_req->num_outstanding_data_wr = 0;
610 	current_data_wr = &rdma_req->data;
611 	for (i = 0; i < current_data_wr->wr.num_sge; i++) {
612 		current_data_wr->wr.sg_list[i].addr = 0;
613 		current_data_wr->wr.sg_list[i].length = 0;
614 		current_data_wr->wr.sg_list[i].lkey = 0;
615 	}
616 	current_data_wr->wr.num_sge = 0;
617 
618 	send_wr = current_data_wr->wr.next;
619 	if (send_wr != NULL && send_wr != &rdma_req->rsp.wr) {
620 		next_data_wr = SPDK_CONTAINEROF(send_wr, struct spdk_nvmf_rdma_request_data, wr);
621 	}
622 	while (next_data_wr) {
623 		current_data_wr = next_data_wr;
624 		send_wr = current_data_wr->wr.next;
625 		if (send_wr != NULL && send_wr != &rdma_req->rsp.wr) {
626 			next_data_wr = SPDK_CONTAINEROF(send_wr, struct spdk_nvmf_rdma_request_data, wr);
627 		} else {
628 			next_data_wr = NULL;
629 		}
630 
631 		for (i = 0; i < current_data_wr->wr.num_sge; i++) {
632 			current_data_wr->wr.sg_list[i].addr = 0;
633 			current_data_wr->wr.sg_list[i].length = 0;
634 			current_data_wr->wr.sg_list[i].lkey = 0;
635 		}
636 		current_data_wr->wr.num_sge = 0;
637 		spdk_mempool_put(rtransport->data_wr_pool, current_data_wr);
638 	}
639 }
640 
641 static void
642 nvmf_rdma_dump_request(struct spdk_nvmf_rdma_request *req)
643 {
644 	SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", req->data_from_pool);
645 	if (req->req.cmd) {
646 		SPDK_ERRLOG("\t\tRequest opcode: %d\n", req->req.cmd->nvmf_cmd.opcode);
647 	}
648 	if (req->recv) {
649 		SPDK_ERRLOG("\t\tRequest recv wr_id%lu\n", req->recv->wr.wr_id);
650 	}
651 }
652 
653 static void
654 nvmf_rdma_dump_qpair_contents(struct spdk_nvmf_rdma_qpair *rqpair)
655 {
656 	int i;
657 
658 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", rqpair->qpair.qid);
659 	for (i = 0; i < rqpair->max_queue_depth; i++) {
660 		if (rqpair->resources->reqs[i].state != RDMA_REQUEST_STATE_FREE) {
661 			nvmf_rdma_dump_request(&rqpair->resources->reqs[i]);
662 		}
663 	}
664 }
665 
666 static void
667 nvmf_rdma_resources_destroy(struct spdk_nvmf_rdma_resources *resources)
668 {
669 	if (resources->cmds_mr) {
670 		ibv_dereg_mr(resources->cmds_mr);
671 	}
672 
673 	if (resources->cpls_mr) {
674 		ibv_dereg_mr(resources->cpls_mr);
675 	}
676 
677 	if (resources->bufs_mr) {
678 		ibv_dereg_mr(resources->bufs_mr);
679 	}
680 
681 	spdk_dma_free(resources->cmds);
682 	spdk_dma_free(resources->cpls);
683 	spdk_dma_free(resources->bufs);
684 	free(resources->reqs);
685 	free(resources->recvs);
686 	free(resources);
687 }
688 
689 
690 static struct spdk_nvmf_rdma_resources *
691 nvmf_rdma_resources_create(struct spdk_nvmf_rdma_resource_opts *opts)
692 {
693 	struct spdk_nvmf_rdma_resources	*resources;
694 	struct spdk_nvmf_rdma_request	*rdma_req;
695 	struct spdk_nvmf_rdma_recv	*rdma_recv;
696 	struct ibv_qp			*qp;
697 	struct ibv_srq			*srq;
698 	uint32_t			i;
699 	int				rc;
700 
701 	resources = calloc(1, sizeof(struct spdk_nvmf_rdma_resources));
702 	if (!resources) {
703 		SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
704 		return NULL;
705 	}
706 
707 	resources->reqs = calloc(opts->max_queue_depth, sizeof(*resources->reqs));
708 	resources->recvs = calloc(opts->max_queue_depth, sizeof(*resources->recvs));
709 	resources->cmds = spdk_dma_zmalloc(opts->max_queue_depth * sizeof(*resources->cmds),
710 					   0x1000, NULL);
711 	resources->cpls = spdk_dma_zmalloc(opts->max_queue_depth * sizeof(*resources->cpls),
712 					   0x1000, NULL);
713 
714 	if (opts->in_capsule_data_size > 0) {
715 		resources->bufs = spdk_dma_zmalloc(opts->max_queue_depth *
716 						   opts->in_capsule_data_size,
717 						   0x1000, NULL);
718 	}
719 
720 	if (!resources->reqs || !resources->recvs || !resources->cmds ||
721 	    !resources->cpls || (opts->in_capsule_data_size && !resources->bufs)) {
722 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
723 		goto cleanup;
724 	}
725 
726 	resources->cmds_mr = ibv_reg_mr(opts->pd, resources->cmds,
727 					opts->max_queue_depth * sizeof(*resources->cmds),
728 					IBV_ACCESS_LOCAL_WRITE);
729 	resources->cpls_mr = ibv_reg_mr(opts->pd, resources->cpls,
730 					opts->max_queue_depth * sizeof(*resources->cpls),
731 					0);
732 
733 	if (opts->in_capsule_data_size) {
734 		resources->bufs_mr = ibv_reg_mr(opts->pd, resources->bufs,
735 						opts->max_queue_depth *
736 						opts->in_capsule_data_size,
737 						IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
738 	}
739 
740 	if (!resources->cmds_mr || !resources->cpls_mr ||
741 	    (opts->in_capsule_data_size &&
742 	     !resources->bufs_mr)) {
743 		goto cleanup;
744 	}
745 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Command Array: %p Length: %lx LKey: %x\n",
746 		      resources->cmds, opts->max_queue_depth * sizeof(*resources->cmds),
747 		      resources->cmds_mr->lkey);
748 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Completion Array: %p Length: %lx LKey: %x\n",
749 		      resources->cpls, opts->max_queue_depth * sizeof(*resources->cpls),
750 		      resources->cpls_mr->lkey);
751 	if (resources->bufs && resources->bufs_mr) {
752 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "In Capsule Data Array: %p Length: %x LKey: %x\n",
753 			      resources->bufs, opts->max_queue_depth *
754 			      opts->in_capsule_data_size, resources->bufs_mr->lkey);
755 	}
756 
757 	/* Initialize queues */
758 	STAILQ_INIT(&resources->incoming_queue);
759 	STAILQ_INIT(&resources->free_queue);
760 
761 	for (i = 0; i < opts->max_queue_depth; i++) {
762 		struct ibv_recv_wr *bad_wr = NULL;
763 
764 		rdma_recv = &resources->recvs[i];
765 		rdma_recv->qpair = opts->qpair;
766 
767 		/* Set up memory to receive commands */
768 		if (resources->bufs) {
769 			rdma_recv->buf = (void *)((uintptr_t)resources->bufs + (i *
770 						  opts->in_capsule_data_size));
771 		}
772 
773 		rdma_recv->rdma_wr.type = RDMA_WR_TYPE_RECV;
774 
775 		rdma_recv->sgl[0].addr = (uintptr_t)&resources->cmds[i];
776 		rdma_recv->sgl[0].length = sizeof(resources->cmds[i]);
777 		rdma_recv->sgl[0].lkey = resources->cmds_mr->lkey;
778 		rdma_recv->wr.num_sge = 1;
779 
780 		if (rdma_recv->buf && resources->bufs_mr) {
781 			rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
782 			rdma_recv->sgl[1].length = opts->in_capsule_data_size;
783 			rdma_recv->sgl[1].lkey = resources->bufs_mr->lkey;
784 			rdma_recv->wr.num_sge++;
785 		}
786 
787 		rdma_recv->wr.wr_id = (uintptr_t)&rdma_recv->rdma_wr;
788 		rdma_recv->wr.sg_list = rdma_recv->sgl;
789 		if (opts->shared) {
790 			srq = (struct ibv_srq *)opts->qp;
791 			rc = ibv_post_srq_recv(srq, &rdma_recv->wr, &bad_wr);
792 		} else {
793 			qp = (struct ibv_qp *)opts->qp;
794 			rc = ibv_post_recv(qp, &rdma_recv->wr, &bad_wr);
795 		}
796 		if (rc) {
797 			goto cleanup;
798 		}
799 	}
800 
801 	for (i = 0; i < opts->max_queue_depth; i++) {
802 		rdma_req = &resources->reqs[i];
803 
804 		if (opts->qpair != NULL) {
805 			rdma_req->req.qpair = &opts->qpair->qpair;
806 		} else {
807 			rdma_req->req.qpair = NULL;
808 		}
809 		rdma_req->req.cmd = NULL;
810 
811 		/* Set up memory to send responses */
812 		rdma_req->req.rsp = &resources->cpls[i];
813 
814 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&resources->cpls[i];
815 		rdma_req->rsp.sgl[0].length = sizeof(resources->cpls[i]);
816 		rdma_req->rsp.sgl[0].lkey = resources->cpls_mr->lkey;
817 
818 		rdma_req->rsp.rdma_wr.type = RDMA_WR_TYPE_SEND;
819 		rdma_req->rsp.wr.wr_id = (uintptr_t)&rdma_req->rsp.rdma_wr;
820 		rdma_req->rsp.wr.next = NULL;
821 		rdma_req->rsp.wr.opcode = IBV_WR_SEND;
822 		rdma_req->rsp.wr.send_flags = IBV_SEND_SIGNALED;
823 		rdma_req->rsp.wr.sg_list = rdma_req->rsp.sgl;
824 		rdma_req->rsp.wr.num_sge = SPDK_COUNTOF(rdma_req->rsp.sgl);
825 
826 		/* Set up memory for data buffers */
827 		rdma_req->data.rdma_wr.type = RDMA_WR_TYPE_DATA;
828 		rdma_req->data.wr.wr_id = (uintptr_t)&rdma_req->data.rdma_wr;
829 		rdma_req->data.wr.next = NULL;
830 		rdma_req->data.wr.send_flags = IBV_SEND_SIGNALED;
831 		rdma_req->data.wr.sg_list = rdma_req->data.sgl;
832 		rdma_req->data.wr.num_sge = SPDK_COUNTOF(rdma_req->data.sgl);
833 
834 		/* Initialize request state to FREE */
835 		rdma_req->state = RDMA_REQUEST_STATE_FREE;
836 		STAILQ_INSERT_TAIL(&resources->free_queue, rdma_req, state_link);
837 	}
838 
839 	return resources;
840 
841 cleanup:
842 	nvmf_rdma_resources_destroy(resources);
843 	return NULL;
844 }
845 
846 static void
847 spdk_nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
848 {
849 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
850 	struct ibv_recv_wr		*bad_recv_wr = NULL;
851 	int				rc;
852 
853 	spdk_trace_record(TRACE_RDMA_QP_DESTROY, 0, 0, (uintptr_t)rqpair->cm_id, 0);
854 
855 	spdk_poller_unregister(&rqpair->destruct_poller);
856 
857 	if (rqpair->qd != 0) {
858 		if (rqpair->srq == NULL) {
859 			nvmf_rdma_dump_qpair_contents(rqpair);
860 		}
861 		SPDK_WARNLOG("Destroying qpair when queue depth is %d\n", rqpair->qd);
862 	}
863 
864 	if (rqpair->poller) {
865 		TAILQ_REMOVE(&rqpair->poller->qpairs, rqpair, link);
866 
867 		if (rqpair->srq != NULL) {
868 			/* Drop all received but unprocessed commands for this queue and return them to SRQ */
869 			STAILQ_FOREACH_SAFE(rdma_recv, &rqpair->resources->incoming_queue, link, recv_tmp) {
870 				if (rqpair == rdma_recv->qpair) {
871 					STAILQ_REMOVE_HEAD(&rqpair->resources->incoming_queue, link);
872 					rc = ibv_post_srq_recv(rqpair->srq, &rdma_recv->wr, &bad_recv_wr);
873 					if (rc) {
874 						SPDK_ERRLOG("Unable to re-post rx descriptor\n");
875 					}
876 				}
877 			}
878 		}
879 	}
880 
881 	if (rqpair->cm_id) {
882 		rdma_destroy_qp(rqpair->cm_id);
883 		rdma_destroy_id(rqpair->cm_id);
884 
885 		if (rqpair->poller != NULL && rqpair->srq == NULL) {
886 			rqpair->poller->required_num_wr -= MAX_WR_PER_QP(rqpair->max_queue_depth);
887 		}
888 	}
889 
890 	if (rqpair->srq == NULL) {
891 		nvmf_rdma_resources_destroy(rqpair->resources);
892 	}
893 
894 	free(rqpair);
895 }
896 
897 static int
898 nvmf_rdma_resize_cq(struct spdk_nvmf_rdma_qpair *rqpair, struct spdk_nvmf_rdma_device *device)
899 {
900 	struct spdk_nvmf_rdma_poller	*rpoller;
901 	int				rc, num_cqe, required_num_wr;
902 
903 	/* Enlarge CQ size dynamically */
904 	rpoller = rqpair->poller;
905 	required_num_wr = rpoller->required_num_wr + MAX_WR_PER_QP(rqpair->max_queue_depth);
906 	num_cqe = rpoller->num_cqe;
907 	if (num_cqe < required_num_wr) {
908 		num_cqe = spdk_max(num_cqe * 2, required_num_wr);
909 		num_cqe = spdk_min(num_cqe, device->attr.max_cqe);
910 	}
911 
912 	if (rpoller->num_cqe != num_cqe) {
913 		if (required_num_wr > device->attr.max_cqe) {
914 			SPDK_ERRLOG("RDMA CQE requirement (%d) exceeds device max_cqe limitation (%d)\n",
915 				    required_num_wr, device->attr.max_cqe);
916 			return -1;
917 		}
918 
919 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Resize RDMA CQ from %d to %d\n", rpoller->num_cqe, num_cqe);
920 		rc = ibv_resize_cq(rpoller->cq, num_cqe);
921 		if (rc) {
922 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
923 			return -1;
924 		}
925 
926 		rpoller->num_cqe = num_cqe;
927 	}
928 
929 	rpoller->required_num_wr = required_num_wr;
930 	return 0;
931 }
932 
933 static int
934 spdk_nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
935 {
936 	struct spdk_nvmf_rdma_qpair		*rqpair;
937 	int					rc;
938 	struct spdk_nvmf_rdma_transport		*rtransport;
939 	struct spdk_nvmf_transport		*transport;
940 	struct spdk_nvmf_rdma_resource_opts	opts;
941 	struct spdk_nvmf_rdma_device		*device;
942 	struct ibv_qp_init_attr			ibv_init_attr;
943 
944 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
945 	device = rqpair->port->device;
946 
947 	memset(&ibv_init_attr, 0, sizeof(struct ibv_qp_init_attr));
948 	ibv_init_attr.qp_context	= rqpair;
949 	ibv_init_attr.qp_type		= IBV_QPT_RC;
950 	ibv_init_attr.send_cq		= rqpair->poller->cq;
951 	ibv_init_attr.recv_cq		= rqpair->poller->cq;
952 
953 	if (rqpair->srq) {
954 		ibv_init_attr.srq		= rqpair->srq;
955 	} else {
956 		ibv_init_attr.cap.max_recv_wr	= rqpair->max_queue_depth +
957 						  1; /* RECV operations + dummy drain WR */
958 	}
959 
960 	ibv_init_attr.cap.max_send_wr	= rqpair->max_queue_depth *
961 					  2 + 1; /* SEND, READ, and WRITE operations + dummy drain WR */
962 	ibv_init_attr.cap.max_send_sge	= spdk_min(device->attr.max_sge, NVMF_DEFAULT_TX_SGE);
963 	ibv_init_attr.cap.max_recv_sge	= spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
964 
965 	if (rqpair->srq == NULL && nvmf_rdma_resize_cq(rqpair, device) < 0) {
966 		SPDK_ERRLOG("Failed to resize the completion queue. Cannot initialize qpair.\n");
967 		goto error;
968 	}
969 
970 	rc = rdma_create_qp(rqpair->cm_id, rqpair->port->device->pd, &ibv_init_attr);
971 	if (rc) {
972 		SPDK_ERRLOG("rdma_create_qp failed: errno %d: %s\n", errno, spdk_strerror(errno));
973 		goto error;
974 	}
975 
976 	rqpair->max_send_depth = spdk_min((uint32_t)(rqpair->max_queue_depth * 2 + 1),
977 					  ibv_init_attr.cap.max_send_wr);
978 	rqpair->max_send_sge = spdk_min(NVMF_DEFAULT_TX_SGE, ibv_init_attr.cap.max_send_sge);
979 	rqpair->max_recv_sge = spdk_min(NVMF_DEFAULT_RX_SGE, ibv_init_attr.cap.max_recv_sge);
980 	spdk_trace_record(TRACE_RDMA_QP_CREATE, 0, 0, (uintptr_t)rqpair->cm_id, 0);
981 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "New RDMA Connection: %p\n", qpair);
982 
983 	if (rqpair->poller->srq == NULL) {
984 		rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
985 		transport = &rtransport->transport;
986 
987 		opts.qp = rqpair->cm_id->qp;
988 		opts.pd = rqpair->cm_id->pd;
989 		opts.qpair = rqpair;
990 		opts.shared = false;
991 		opts.max_queue_depth = rqpair->max_queue_depth;
992 		opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
993 
994 		rqpair->resources = nvmf_rdma_resources_create(&opts);
995 
996 		if (!rqpair->resources) {
997 			SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
998 			goto error;
999 		}
1000 	} else {
1001 		rqpair->resources = rqpair->poller->resources;
1002 	}
1003 
1004 	rqpair->current_recv_depth = 0;
1005 	STAILQ_INIT(&rqpair->pending_rdma_read_queue);
1006 	STAILQ_INIT(&rqpair->pending_rdma_write_queue);
1007 
1008 	return 0;
1009 
1010 error:
1011 	rdma_destroy_id(rqpair->cm_id);
1012 	rqpair->cm_id = NULL;
1013 	spdk_nvmf_rdma_qpair_destroy(rqpair);
1014 	return -1;
1015 }
1016 
1017 static int
1018 request_transfer_in(struct spdk_nvmf_request *req)
1019 {
1020 	int				rc;
1021 	struct spdk_nvmf_rdma_request	*rdma_req;
1022 	struct spdk_nvmf_qpair		*qpair;
1023 	struct spdk_nvmf_rdma_qpair	*rqpair;
1024 	struct ibv_send_wr		*bad_wr = NULL;
1025 
1026 	qpair = req->qpair;
1027 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1028 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1029 
1030 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
1031 	assert(rdma_req != NULL);
1032 
1033 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA READ POSTED. Request: %p Connection: %p\n", req, qpair);
1034 
1035 	rc = ibv_post_send(rqpair->cm_id->qp, &rdma_req->data.wr, &bad_wr);
1036 	if (rc) {
1037 		SPDK_ERRLOG("Unable to transfer data from host to target\n");
1038 		return -1;
1039 	}
1040 	rqpair->current_read_depth += rdma_req->num_outstanding_data_wr;
1041 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr;
1042 	return 0;
1043 }
1044 
1045 static int
1046 request_transfer_out(struct spdk_nvmf_request *req, int *data_posted)
1047 {
1048 	int				rc;
1049 	struct spdk_nvmf_rdma_request	*rdma_req;
1050 	struct spdk_nvmf_qpair		*qpair;
1051 	struct spdk_nvmf_rdma_qpair	*rqpair;
1052 	struct spdk_nvme_cpl		*rsp;
1053 	struct ibv_recv_wr		*bad_recv_wr = NULL;
1054 	struct ibv_send_wr		*send_wr, *bad_send_wr = NULL;
1055 
1056 	*data_posted = 0;
1057 	qpair = req->qpair;
1058 	rsp = &req->rsp->nvme_cpl;
1059 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1060 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1061 
1062 	/* Advance our sq_head pointer */
1063 	if (qpair->sq_head == qpair->sq_head_max) {
1064 		qpair->sq_head = 0;
1065 	} else {
1066 		qpair->sq_head++;
1067 	}
1068 	rsp->sqhd = qpair->sq_head;
1069 
1070 	/* Post the capsule to the recv buffer */
1071 	assert(rdma_req->recv != NULL);
1072 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA RECV POSTED. Recv: %p Connection: %p\n", rdma_req->recv,
1073 		      rqpair);
1074 	if (rqpair->srq == NULL) {
1075 		rc = ibv_post_recv(rqpair->cm_id->qp, &rdma_req->recv->wr, &bad_recv_wr);
1076 	} else {
1077 		rdma_req->recv->qpair = NULL;
1078 		rc = ibv_post_srq_recv(rqpair->srq, &rdma_req->recv->wr, &bad_recv_wr);
1079 	}
1080 
1081 	if (rc) {
1082 		SPDK_ERRLOG("Unable to re-post rx descriptor\n");
1083 		return rc;
1084 	}
1085 	rdma_req->recv = NULL;
1086 	assert(rqpair->current_recv_depth > 0);
1087 	rqpair->current_recv_depth--;
1088 
1089 	/* Build the response which consists of optional
1090 	 * RDMA WRITEs to transfer data, plus an RDMA SEND
1091 	 * containing the response.
1092 	 */
1093 	send_wr = &rdma_req->rsp.wr;
1094 
1095 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
1096 	    req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1097 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA WRITE POSTED. Request: %p Connection: %p\n", req, qpair);
1098 		send_wr = &rdma_req->data.wr;
1099 		*data_posted = 1;
1100 	}
1101 
1102 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA SEND POSTED. Request: %p Connection: %p\n", req, qpair);
1103 
1104 	/* Send the completion */
1105 	rc = ibv_post_send(rqpair->cm_id->qp, send_wr, &bad_send_wr);
1106 	if (rc) {
1107 		SPDK_ERRLOG("Unable to send response capsule\n");
1108 		return rc;
1109 	}
1110 	/* +1 for the rsp wr */
1111 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr + 1;
1112 
1113 	return 0;
1114 }
1115 
1116 static int
1117 spdk_nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
1118 {
1119 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
1120 	struct rdma_conn_param				ctrlr_event_data = {};
1121 	int						rc;
1122 
1123 	accept_data.recfmt = 0;
1124 	accept_data.crqsize = rqpair->max_queue_depth;
1125 
1126 	ctrlr_event_data.private_data = &accept_data;
1127 	ctrlr_event_data.private_data_len = sizeof(accept_data);
1128 	if (id->ps == RDMA_PS_TCP) {
1129 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
1130 		ctrlr_event_data.initiator_depth = rqpair->max_read_depth;
1131 	}
1132 
1133 	rc = rdma_accept(id, &ctrlr_event_data);
1134 	if (rc) {
1135 		SPDK_ERRLOG("Error %d on rdma_accept\n", errno);
1136 	} else {
1137 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Sent back the accept\n");
1138 	}
1139 
1140 	return rc;
1141 }
1142 
1143 static void
1144 spdk_nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
1145 {
1146 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
1147 
1148 	rej_data.recfmt = 0;
1149 	rej_data.sts = error;
1150 
1151 	rdma_reject(id, &rej_data, sizeof(rej_data));
1152 }
1153 
1154 static int
1155 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event,
1156 		  new_qpair_fn cb_fn)
1157 {
1158 	struct spdk_nvmf_rdma_transport *rtransport;
1159 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
1160 	struct spdk_nvmf_rdma_port	*port;
1161 	struct rdma_conn_param		*rdma_param = NULL;
1162 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
1163 	uint16_t			max_queue_depth;
1164 	uint16_t			max_read_depth;
1165 
1166 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1167 
1168 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
1169 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
1170 
1171 	rdma_param = &event->param.conn;
1172 	if (rdma_param->private_data == NULL ||
1173 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1174 		SPDK_ERRLOG("connect request: no private data provided\n");
1175 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
1176 		return -1;
1177 	}
1178 
1179 	private_data = rdma_param->private_data;
1180 	if (private_data->recfmt != 0) {
1181 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
1182 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
1183 		return -1;
1184 	}
1185 
1186 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Connect Recv on fabric intf name %s, dev_name %s\n",
1187 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
1188 
1189 	port = event->listen_id->context;
1190 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
1191 		      event->listen_id, event->listen_id->verbs, port);
1192 
1193 	/* Figure out the supported queue depth. This is a multi-step process
1194 	 * that takes into account hardware maximums, host provided values,
1195 	 * and our target's internal memory limits */
1196 
1197 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Calculating Queue Depth\n");
1198 
1199 	/* Start with the maximum queue depth allowed by the target */
1200 	max_queue_depth = rtransport->transport.opts.max_queue_depth;
1201 	max_read_depth = rtransport->transport.opts.max_queue_depth;
1202 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Target Max Queue Depth: %d\n",
1203 		      rtransport->transport.opts.max_queue_depth);
1204 
1205 	/* Next check the local NIC's hardware limitations */
1206 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
1207 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
1208 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
1209 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
1210 	max_read_depth = spdk_min(max_read_depth, port->device->attr.max_qp_init_rd_atom);
1211 
1212 	/* Next check the remote NIC's hardware limitations */
1213 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
1214 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
1215 		      rdma_param->initiator_depth, rdma_param->responder_resources);
1216 	if (rdma_param->initiator_depth > 0) {
1217 		max_read_depth = spdk_min(max_read_depth, rdma_param->initiator_depth);
1218 	}
1219 
1220 	/* Finally check for the host software requested values, which are
1221 	 * optional. */
1222 	if (rdma_param->private_data != NULL &&
1223 	    rdma_param->private_data_len >= sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1224 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1225 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Send Queue Size: %d\n", private_data->hsqsize);
1226 		max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
1227 		max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
1228 	}
1229 
1230 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
1231 		      max_queue_depth, max_read_depth);
1232 
1233 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
1234 	if (rqpair == NULL) {
1235 		SPDK_ERRLOG("Could not allocate new connection.\n");
1236 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1237 		return -1;
1238 	}
1239 
1240 	rqpair->port = port;
1241 	rqpair->max_queue_depth = max_queue_depth;
1242 	rqpair->max_read_depth = max_read_depth;
1243 	rqpair->cm_id = event->id;
1244 	rqpair->listen_id = event->listen_id;
1245 	rqpair->qpair.transport = transport;
1246 
1247 	event->id->context = &rqpair->qpair;
1248 
1249 	cb_fn(&rqpair->qpair);
1250 
1251 	return 0;
1252 }
1253 
1254 static int
1255 spdk_nvmf_rdma_mem_notify(void *cb_ctx, struct spdk_mem_map *map,
1256 			  enum spdk_mem_map_notify_action action,
1257 			  void *vaddr, size_t size)
1258 {
1259 	struct ibv_pd *pd = cb_ctx;
1260 	struct ibv_mr *mr;
1261 
1262 	switch (action) {
1263 	case SPDK_MEM_MAP_NOTIFY_REGISTER:
1264 		if (!g_nvmf_hooks.get_rkey) {
1265 			mr = ibv_reg_mr(pd, vaddr, size,
1266 					IBV_ACCESS_LOCAL_WRITE |
1267 					IBV_ACCESS_REMOTE_READ |
1268 					IBV_ACCESS_REMOTE_WRITE);
1269 			if (mr == NULL) {
1270 				SPDK_ERRLOG("ibv_reg_mr() failed\n");
1271 				return -1;
1272 			} else {
1273 				spdk_mem_map_set_translation(map, (uint64_t)vaddr, size, (uint64_t)mr);
1274 			}
1275 		} else {
1276 			spdk_mem_map_set_translation(map, (uint64_t)vaddr, size,
1277 						     g_nvmf_hooks.get_rkey(pd, vaddr, size));
1278 		}
1279 		break;
1280 	case SPDK_MEM_MAP_NOTIFY_UNREGISTER:
1281 		if (!g_nvmf_hooks.get_rkey) {
1282 			mr = (struct ibv_mr *)spdk_mem_map_translate(map, (uint64_t)vaddr, NULL);
1283 			spdk_mem_map_clear_translation(map, (uint64_t)vaddr, size);
1284 			if (mr) {
1285 				ibv_dereg_mr(mr);
1286 			}
1287 		}
1288 		break;
1289 	}
1290 
1291 	return 0;
1292 }
1293 
1294 static int
1295 spdk_nvmf_rdma_check_contiguous_entries(uint64_t addr_1, uint64_t addr_2)
1296 {
1297 	/* Two contiguous mappings will point to the same address which is the start of the RDMA MR. */
1298 	return addr_1 == addr_2;
1299 }
1300 
1301 static void
1302 spdk_nvmf_rdma_request_free_buffers(struct spdk_nvmf_rdma_request *rdma_req,
1303 				    struct spdk_nvmf_transport_poll_group *group, struct spdk_nvmf_transport *transport,
1304 				    uint32_t num_buffers)
1305 {
1306 	uint32_t i;
1307 
1308 	for (i = 0; i < num_buffers; i++) {
1309 		if (group->buf_cache_count < group->buf_cache_size) {
1310 			STAILQ_INSERT_HEAD(&group->buf_cache,
1311 					   (struct spdk_nvmf_transport_pg_cache_buf *)rdma_req->buffers[i], link);
1312 			group->buf_cache_count++;
1313 		} else {
1314 			spdk_mempool_put(transport->data_buf_pool, rdma_req->buffers[i]);
1315 		}
1316 		rdma_req->req.iov[i].iov_base = NULL;
1317 		rdma_req->buffers[i] = NULL;
1318 		rdma_req->req.iov[i].iov_len = 0;
1319 
1320 	}
1321 	rdma_req->data_from_pool = false;
1322 }
1323 
1324 static int
1325 nvmf_rdma_request_get_buffers(struct spdk_nvmf_rdma_request *rdma_req,
1326 			      struct spdk_nvmf_transport_poll_group *group, struct spdk_nvmf_transport *transport,
1327 			      uint32_t num_buffers)
1328 {
1329 	uint32_t i = 0;
1330 
1331 	while (i < num_buffers) {
1332 		if (!(STAILQ_EMPTY(&group->buf_cache))) {
1333 			group->buf_cache_count--;
1334 			rdma_req->buffers[i] = STAILQ_FIRST(&group->buf_cache);
1335 			STAILQ_REMOVE_HEAD(&group->buf_cache, link);
1336 			assert(rdma_req->buffers[i] != NULL);
1337 			i++;
1338 		} else {
1339 			if (spdk_mempool_get_bulk(transport->data_buf_pool, &rdma_req->buffers[i], num_buffers - i)) {
1340 				goto err_exit;
1341 			}
1342 			i += num_buffers - i;
1343 		}
1344 	}
1345 
1346 	return 0;
1347 
1348 err_exit:
1349 	spdk_nvmf_rdma_request_free_buffers(rdma_req, group, transport, i);
1350 	return -ENOMEM;
1351 }
1352 
1353 typedef enum spdk_nvme_data_transfer spdk_nvme_data_transfer_t;
1354 
1355 static spdk_nvme_data_transfer_t
1356 spdk_nvmf_rdma_request_get_xfer(struct spdk_nvmf_rdma_request *rdma_req)
1357 {
1358 	enum spdk_nvme_data_transfer xfer;
1359 	struct spdk_nvme_cmd *cmd = &rdma_req->req.cmd->nvme_cmd;
1360 	struct spdk_nvme_sgl_descriptor *sgl = &cmd->dptr.sgl1;
1361 
1362 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1363 	rdma_req->rsp.wr.opcode = IBV_WR_SEND;
1364 	rdma_req->rsp.wr.imm_data = 0;
1365 #endif
1366 
1367 	/* Figure out data transfer direction */
1368 	if (cmd->opc == SPDK_NVME_OPC_FABRIC) {
1369 		xfer = spdk_nvme_opc_get_data_transfer(rdma_req->req.cmd->nvmf_cmd.fctype);
1370 	} else {
1371 		xfer = spdk_nvme_opc_get_data_transfer(cmd->opc);
1372 
1373 		/* Some admin commands are special cases */
1374 		if ((rdma_req->req.qpair->qid == 0) &&
1375 		    ((cmd->opc == SPDK_NVME_OPC_GET_FEATURES) ||
1376 		     (cmd->opc == SPDK_NVME_OPC_SET_FEATURES))) {
1377 			switch (cmd->cdw10 & 0xff) {
1378 			case SPDK_NVME_FEAT_LBA_RANGE_TYPE:
1379 			case SPDK_NVME_FEAT_AUTONOMOUS_POWER_STATE_TRANSITION:
1380 			case SPDK_NVME_FEAT_HOST_IDENTIFIER:
1381 				break;
1382 			default:
1383 				xfer = SPDK_NVME_DATA_NONE;
1384 			}
1385 		}
1386 	}
1387 
1388 	if (xfer == SPDK_NVME_DATA_NONE) {
1389 		return xfer;
1390 	}
1391 
1392 	/* Even for commands that may transfer data, they could have specified 0 length.
1393 	 * We want those to show up with xfer SPDK_NVME_DATA_NONE.
1394 	 */
1395 	switch (sgl->generic.type) {
1396 	case SPDK_NVME_SGL_TYPE_DATA_BLOCK:
1397 	case SPDK_NVME_SGL_TYPE_BIT_BUCKET:
1398 	case SPDK_NVME_SGL_TYPE_SEGMENT:
1399 	case SPDK_NVME_SGL_TYPE_LAST_SEGMENT:
1400 	case SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK:
1401 		if (sgl->unkeyed.length == 0) {
1402 			xfer = SPDK_NVME_DATA_NONE;
1403 		}
1404 		break;
1405 	case SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK:
1406 		if (sgl->keyed.length == 0) {
1407 			xfer = SPDK_NVME_DATA_NONE;
1408 		}
1409 		break;
1410 	}
1411 
1412 	return xfer;
1413 }
1414 
1415 static int
1416 nvmf_request_alloc_wrs(struct spdk_nvmf_rdma_transport *rtransport,
1417 		       struct spdk_nvmf_rdma_request *rdma_req,
1418 		       uint32_t num_sgl_descriptors)
1419 {
1420 	struct spdk_nvmf_rdma_request_data	*work_requests[SPDK_NVMF_MAX_SGL_ENTRIES];
1421 	struct spdk_nvmf_rdma_request_data	*current_data_wr;
1422 	uint32_t				i;
1423 
1424 	if (spdk_mempool_get_bulk(rtransport->data_wr_pool, (void **)work_requests, num_sgl_descriptors)) {
1425 		return -ENOMEM;
1426 	}
1427 
1428 	current_data_wr = &rdma_req->data;
1429 
1430 	for (i = 0; i < num_sgl_descriptors; i++) {
1431 		if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1432 			current_data_wr->wr.opcode = IBV_WR_RDMA_WRITE;
1433 		} else if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1434 			current_data_wr->wr.opcode = IBV_WR_RDMA_READ;
1435 		} else {
1436 			assert(false);
1437 		}
1438 		work_requests[i]->wr.send_flags = IBV_SEND_SIGNALED;
1439 		work_requests[i]->wr.sg_list = work_requests[i]->sgl;
1440 		work_requests[i]->wr.wr_id = rdma_req->data.wr.wr_id;
1441 		current_data_wr->wr.next = &work_requests[i]->wr;
1442 		current_data_wr = work_requests[i];
1443 	}
1444 
1445 	if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1446 		current_data_wr->wr.opcode = IBV_WR_RDMA_WRITE;
1447 		current_data_wr->wr.next = &rdma_req->rsp.wr;
1448 	} else if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1449 		current_data_wr->wr.opcode = IBV_WR_RDMA_READ;
1450 		current_data_wr->wr.next = NULL;
1451 	}
1452 	return 0;
1453 }
1454 
1455 static int
1456 nvmf_rdma_fill_buffers(struct spdk_nvmf_rdma_transport *rtransport,
1457 		       struct spdk_nvmf_rdma_poll_group *rgroup,
1458 		       struct spdk_nvmf_rdma_device *device,
1459 		       struct spdk_nvmf_rdma_request *rdma_req,
1460 		       struct ibv_send_wr *wr,
1461 		       uint32_t length)
1462 {
1463 	uint64_t	translation_len;
1464 	uint32_t	remaining_length = length;
1465 	uint32_t	iovcnt;
1466 	uint32_t	i = 0;
1467 
1468 
1469 	while (remaining_length) {
1470 		iovcnt = rdma_req->req.iovcnt;
1471 		rdma_req->req.iov[iovcnt].iov_base = (void *)((uintptr_t)(rdma_req->buffers[iovcnt] +
1472 						     NVMF_DATA_BUFFER_MASK) &
1473 						     ~NVMF_DATA_BUFFER_MASK);
1474 		rdma_req->req.iov[iovcnt].iov_len  = spdk_min(remaining_length,
1475 						     rtransport->transport.opts.io_unit_size);
1476 		rdma_req->req.iovcnt++;
1477 		wr->sg_list[i].addr = (uintptr_t)(rdma_req->req.iov[iovcnt].iov_base);
1478 		wr->sg_list[i].length = rdma_req->req.iov[iovcnt].iov_len;
1479 		translation_len = rdma_req->req.iov[iovcnt].iov_len;
1480 
1481 		if (!g_nvmf_hooks.get_rkey) {
1482 			wr->sg_list[i].lkey = ((struct ibv_mr *)spdk_mem_map_translate(device->map,
1483 					       (uint64_t)rdma_req->buffers[iovcnt], &translation_len))->lkey;
1484 		} else {
1485 			wr->sg_list[i].lkey = spdk_mem_map_translate(device->map,
1486 					      (uint64_t)rdma_req->buffers[iovcnt], &translation_len);
1487 		}
1488 
1489 		remaining_length -= rdma_req->req.iov[iovcnt].iov_len;
1490 
1491 		if (translation_len < rdma_req->req.iov[iovcnt].iov_len) {
1492 			SPDK_ERRLOG("Data buffer split over multiple RDMA Memory Regions\n");
1493 			return -EINVAL;
1494 		}
1495 		i++;
1496 	}
1497 
1498 	return 0;
1499 }
1500 
1501 static int
1502 spdk_nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1503 				 struct spdk_nvmf_rdma_device *device,
1504 				 struct spdk_nvmf_rdma_request *rdma_req)
1505 {
1506 	struct spdk_nvmf_rdma_qpair		*rqpair;
1507 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1508 	uint32_t				num_buffers;
1509 	uint32_t				i = 0;
1510 	int					rc = 0;
1511 
1512 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1513 	rgroup = rqpair->poller->group;
1514 	rdma_req->req.iovcnt = 0;
1515 
1516 	num_buffers = rdma_req->req.length / rtransport->transport.opts.io_unit_size;
1517 	if (rdma_req->req.length % rtransport->transport.opts.io_unit_size) {
1518 		num_buffers++;
1519 	}
1520 
1521 	if (nvmf_rdma_request_get_buffers(rdma_req, &rgroup->group, &rtransport->transport, num_buffers)) {
1522 		return -ENOMEM;
1523 	}
1524 
1525 	rdma_req->req.iovcnt = 0;
1526 
1527 	rc = nvmf_rdma_fill_buffers(rtransport, rgroup, device, rdma_req, &rdma_req->data.wr,
1528 				    rdma_req->req.length);
1529 	if (rc != 0) {
1530 		goto err_exit;
1531 	}
1532 
1533 	assert(rdma_req->req.iovcnt <= rqpair->max_send_sge);
1534 
1535 	rdma_req->data_from_pool = true;
1536 
1537 	return rc;
1538 
1539 err_exit:
1540 	spdk_nvmf_rdma_request_free_buffers(rdma_req, &rgroup->group, &rtransport->transport, num_buffers);
1541 	while (i) {
1542 		i--;
1543 		rdma_req->data.wr.sg_list[i].addr = 0;
1544 		rdma_req->data.wr.sg_list[i].length = 0;
1545 		rdma_req->data.wr.sg_list[i].lkey = 0;
1546 	}
1547 	rdma_req->req.iovcnt = 0;
1548 	return rc;
1549 }
1550 
1551 static int
1552 nvmf_rdma_request_fill_iovs_multi_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1553 				      struct spdk_nvmf_rdma_device *device,
1554 				      struct spdk_nvmf_rdma_request *rdma_req)
1555 {
1556 	struct spdk_nvmf_rdma_qpair		*rqpair;
1557 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1558 	struct ibv_send_wr			*current_wr;
1559 	struct spdk_nvmf_request		*req = &rdma_req->req;
1560 	struct spdk_nvme_sgl_descriptor		*inline_segment, *desc;
1561 	uint32_t				num_sgl_descriptors;
1562 	uint32_t				num_buffers = 0;
1563 	uint32_t				i;
1564 	int					rc;
1565 
1566 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1567 	rgroup = rqpair->poller->group;
1568 
1569 	inline_segment = &req->cmd->nvme_cmd.dptr.sgl1;
1570 	assert(inline_segment->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT);
1571 	assert(inline_segment->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET);
1572 
1573 	num_sgl_descriptors = inline_segment->unkeyed.length / sizeof(struct spdk_nvme_sgl_descriptor);
1574 	assert(num_sgl_descriptors <= SPDK_NVMF_MAX_SGL_ENTRIES);
1575 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1576 
1577 	for (i = 0; i < num_sgl_descriptors; i++) {
1578 		num_buffers += desc->keyed.length / rtransport->transport.opts.io_unit_size;
1579 		if (desc->keyed.length % rtransport->transport.opts.io_unit_size) {
1580 			num_buffers++;
1581 		}
1582 		desc++;
1583 	}
1584 	/* If the number of buffers is too large, then we know the I/O is larger than allowed. Fail it. */
1585 	if (num_buffers > NVMF_REQ_MAX_BUFFERS) {
1586 		return -EINVAL;
1587 	}
1588 	if (nvmf_rdma_request_get_buffers(rdma_req, &rgroup->group, &rtransport->transport,
1589 					  num_buffers) != 0) {
1590 		return -ENOMEM;
1591 	}
1592 
1593 	if (nvmf_request_alloc_wrs(rtransport, rdma_req, num_sgl_descriptors - 1) != 0) {
1594 		spdk_nvmf_rdma_request_free_buffers(rdma_req, &rgroup->group, &rtransport->transport, num_buffers);
1595 		return -ENOMEM;
1596 	}
1597 
1598 	/* The first WR must always be the embedded data WR. This is how we unwind them later. */
1599 	current_wr = &rdma_req->data.wr;
1600 
1601 	req->iovcnt = 0;
1602 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1603 	for (i = 0; i < num_sgl_descriptors; i++) {
1604 		/* The descriptors must be keyed data block descriptors with an address, not an offset. */
1605 		if (spdk_unlikely(desc->generic.type != SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK ||
1606 				  desc->keyed.subtype != SPDK_NVME_SGL_SUBTYPE_ADDRESS)) {
1607 			rc = -EINVAL;
1608 			goto err_exit;
1609 		}
1610 
1611 		current_wr->num_sge = 0;
1612 		req->length += desc->keyed.length;
1613 
1614 		rc = nvmf_rdma_fill_buffers(rtransport, rgroup, device, rdma_req, current_wr,
1615 					    desc->keyed.length);
1616 		if (rc != 0) {
1617 			rc = -ENOMEM;
1618 			goto err_exit;
1619 		}
1620 
1621 		current_wr->wr.rdma.rkey = desc->keyed.key;
1622 		current_wr->wr.rdma.remote_addr = desc->address;
1623 		current_wr = current_wr->next;
1624 		desc++;
1625 	}
1626 
1627 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1628 	if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1629 		if (desc->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1630 			rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1631 			rdma_req->rsp.wr.imm_data = desc->keyed.key;
1632 		}
1633 	}
1634 #endif
1635 
1636 	rdma_req->num_outstanding_data_wr = num_sgl_descriptors;
1637 	rdma_req->data_from_pool = true;
1638 
1639 	return 0;
1640 
1641 err_exit:
1642 	spdk_nvmf_rdma_request_free_buffers(rdma_req, &rgroup->group, &rtransport->transport, num_buffers);
1643 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1644 	return rc;
1645 }
1646 
1647 static int
1648 spdk_nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1649 				 struct spdk_nvmf_rdma_device *device,
1650 				 struct spdk_nvmf_rdma_request *rdma_req)
1651 {
1652 	struct spdk_nvme_cmd			*cmd;
1653 	struct spdk_nvme_cpl			*rsp;
1654 	struct spdk_nvme_sgl_descriptor		*sgl;
1655 	int					rc;
1656 
1657 	cmd = &rdma_req->req.cmd->nvme_cmd;
1658 	rsp = &rdma_req->req.rsp->nvme_cpl;
1659 	sgl = &cmd->dptr.sgl1;
1660 
1661 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1662 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1663 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1664 		if (sgl->keyed.length > rtransport->transport.opts.max_io_size) {
1665 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1666 				    sgl->keyed.length, rtransport->transport.opts.max_io_size);
1667 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1668 			return -1;
1669 		}
1670 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1671 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1672 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1673 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1674 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1675 			}
1676 		}
1677 #endif
1678 
1679 		/* fill request length and populate iovs */
1680 		rdma_req->req.length = sgl->keyed.length;
1681 
1682 		if (spdk_nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req) < 0) {
1683 			/* No available buffers. Queue this request up. */
1684 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1685 			return 0;
1686 		}
1687 
1688 		/* backward compatible */
1689 		rdma_req->req.data = rdma_req->req.iov[0].iov_base;
1690 
1691 		/* rdma wr specifics */
1692 		rdma_req->data.wr.num_sge = rdma_req->req.iovcnt;
1693 		rdma_req->data.wr.wr.rdma.rkey = sgl->keyed.key;
1694 		rdma_req->data.wr.wr.rdma.remote_addr = sgl->address;
1695 		if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1696 			rdma_req->data.wr.opcode = IBV_WR_RDMA_WRITE;
1697 			rdma_req->data.wr.next = &rdma_req->rsp.wr;
1698 		} else if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1699 			rdma_req->data.wr.opcode = IBV_WR_RDMA_READ;
1700 			rdma_req->data.wr.next = NULL;
1701 		}
1702 
1703 		/* set the number of outstanding data WRs for this request. */
1704 		rdma_req->num_outstanding_data_wr = 1;
1705 
1706 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1707 			      rdma_req->req.iovcnt);
1708 
1709 		return 0;
1710 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1711 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1712 		uint64_t offset = sgl->address;
1713 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1714 
1715 		SPDK_DEBUGLOG(SPDK_LOG_NVMF, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1716 			      offset, sgl->unkeyed.length);
1717 
1718 		if (offset > max_len) {
1719 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1720 				    offset, max_len);
1721 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1722 			return -1;
1723 		}
1724 		max_len -= (uint32_t)offset;
1725 
1726 		if (sgl->unkeyed.length > max_len) {
1727 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1728 				    sgl->unkeyed.length, max_len);
1729 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1730 			return -1;
1731 		}
1732 
1733 		rdma_req->num_outstanding_data_wr = 0;
1734 		rdma_req->req.data = rdma_req->recv->buf + offset;
1735 		rdma_req->data_from_pool = false;
1736 		rdma_req->req.length = sgl->unkeyed.length;
1737 
1738 		rdma_req->req.iov[0].iov_base = rdma_req->req.data;
1739 		rdma_req->req.iov[0].iov_len = rdma_req->req.length;
1740 		rdma_req->req.iovcnt = 1;
1741 
1742 		return 0;
1743 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT &&
1744 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1745 
1746 		rc = nvmf_rdma_request_fill_iovs_multi_sgl(rtransport, device, rdma_req);
1747 		if (rc == -ENOMEM) {
1748 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1749 			return 0;
1750 		} else if (rc == -EINVAL) {
1751 			SPDK_ERRLOG("Multi SGL element request length exceeds the max I/O size\n");
1752 			return -1;
1753 		}
1754 
1755 		/* backward compatible */
1756 		rdma_req->req.data = rdma_req->req.iov[0].iov_base;
1757 
1758 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1759 			      rdma_req->req.iovcnt);
1760 
1761 		return 0;
1762 	}
1763 
1764 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1765 		    sgl->generic.type, sgl->generic.subtype);
1766 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1767 	return -1;
1768 }
1769 
1770 static void
1771 nvmf_rdma_request_free(struct spdk_nvmf_rdma_request *rdma_req,
1772 		       struct spdk_nvmf_rdma_transport	*rtransport)
1773 {
1774 	struct spdk_nvmf_rdma_qpair		*rqpair;
1775 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1776 
1777 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1778 	if (rdma_req->data_from_pool) {
1779 		rgroup = rqpair->poller->group;
1780 
1781 		spdk_nvmf_rdma_request_free_buffers(rdma_req, &rgroup->group, &rtransport->transport,
1782 						    rdma_req->req.iovcnt);
1783 	}
1784 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1785 	rdma_req->req.length = 0;
1786 	rdma_req->req.iovcnt = 0;
1787 	rdma_req->req.data = NULL;
1788 	rdma_req->data.wr.next = NULL;
1789 	rqpair->qd--;
1790 
1791 	STAILQ_INSERT_HEAD(&rqpair->resources->free_queue, rdma_req, state_link);
1792 	rdma_req->state = RDMA_REQUEST_STATE_FREE;
1793 }
1794 
1795 static bool
1796 spdk_nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
1797 			       struct spdk_nvmf_rdma_request *rdma_req)
1798 {
1799 	struct spdk_nvmf_rdma_qpair	*rqpair;
1800 	struct spdk_nvmf_rdma_device	*device;
1801 	struct spdk_nvmf_rdma_poll_group *rgroup;
1802 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
1803 	int				rc;
1804 	struct spdk_nvmf_rdma_recv	*rdma_recv;
1805 	enum spdk_nvmf_rdma_request_state prev_state;
1806 	bool				progress = false;
1807 	int				data_posted;
1808 
1809 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1810 	device = rqpair->port->device;
1811 	rgroup = rqpair->poller->group;
1812 
1813 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
1814 
1815 	/* If the queue pair is in an error state, force the request to the completed state
1816 	 * to release resources. */
1817 	if (rqpair->ibv_state == IBV_QPS_ERR || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1818 		if (rdma_req->state == RDMA_REQUEST_STATE_NEED_BUFFER) {
1819 			TAILQ_REMOVE(&rgroup->pending_data_buf_queue, rdma_req, link);
1820 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING) {
1821 			STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1822 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING) {
1823 			STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1824 		}
1825 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1826 	}
1827 
1828 	/* The loop here is to allow for several back-to-back state changes. */
1829 	do {
1830 		prev_state = rdma_req->state;
1831 
1832 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p entering state %d\n", rdma_req, prev_state);
1833 
1834 		switch (rdma_req->state) {
1835 		case RDMA_REQUEST_STATE_FREE:
1836 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
1837 			 * to escape this state. */
1838 			break;
1839 		case RDMA_REQUEST_STATE_NEW:
1840 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
1841 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1842 			rdma_recv = rdma_req->recv;
1843 
1844 			/* The first element of the SGL is the NVMe command */
1845 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
1846 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
1847 
1848 			if (rqpair->ibv_state == IBV_QPS_ERR  || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1849 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1850 				break;
1851 			}
1852 
1853 			/* The next state transition depends on the data transfer needs of this request. */
1854 			rdma_req->req.xfer = spdk_nvmf_rdma_request_get_xfer(rdma_req);
1855 
1856 			/* If no data to transfer, ready to execute. */
1857 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
1858 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1859 				break;
1860 			}
1861 
1862 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
1863 			TAILQ_INSERT_TAIL(&rgroup->pending_data_buf_queue, rdma_req, link);
1864 			break;
1865 		case RDMA_REQUEST_STATE_NEED_BUFFER:
1866 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
1867 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1868 
1869 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
1870 
1871 			if (rdma_req != TAILQ_FIRST(&rgroup->pending_data_buf_queue)) {
1872 				/* This request needs to wait in line to obtain a buffer */
1873 				break;
1874 			}
1875 
1876 			/* Try to get a data buffer */
1877 			rc = spdk_nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
1878 			if (rc < 0) {
1879 				TAILQ_REMOVE(&rgroup->pending_data_buf_queue, rdma_req, link);
1880 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
1881 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1882 				break;
1883 			}
1884 
1885 			if (!rdma_req->req.data) {
1886 				/* No buffers available. */
1887 				break;
1888 			}
1889 
1890 			TAILQ_REMOVE(&rgroup->pending_data_buf_queue, rdma_req, link);
1891 
1892 			/* If data is transferring from host to controller and the data didn't
1893 			 * arrive using in capsule data, we need to do a transfer from the host.
1894 			 */
1895 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER && rdma_req->data_from_pool) {
1896 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
1897 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
1898 				break;
1899 			}
1900 
1901 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1902 			break;
1903 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
1904 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING, 0, 0,
1905 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1906 
1907 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_read_queue)) {
1908 				/* This request needs to wait in line to perform RDMA */
1909 				break;
1910 			}
1911 			if (rqpair->current_send_depth + rdma_req->num_outstanding_data_wr > rqpair->max_send_depth
1912 			    || rqpair->current_read_depth + rdma_req->num_outstanding_data_wr > rqpair->max_read_depth) {
1913 				/* We can only have so many WRs outstanding. we have to wait until some finish. */
1914 				break;
1915 			}
1916 
1917 			/* We have already verified that this request is the head of the queue. */
1918 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_read_queue, state_link);
1919 
1920 			rc = request_transfer_in(&rdma_req->req);
1921 			if (!rc) {
1922 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
1923 			} else {
1924 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
1925 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1926 			}
1927 			break;
1928 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
1929 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
1930 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1931 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
1932 			 * to escape this state. */
1933 			break;
1934 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
1935 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
1936 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1937 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
1938 			spdk_nvmf_request_exec(&rdma_req->req);
1939 			break;
1940 		case RDMA_REQUEST_STATE_EXECUTING:
1941 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
1942 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1943 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
1944 			 * to escape this state. */
1945 			break;
1946 		case RDMA_REQUEST_STATE_EXECUTED:
1947 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
1948 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1949 			if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1950 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_write_queue, rdma_req, state_link);
1951 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING;
1952 			} else {
1953 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1954 			}
1955 			break;
1956 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
1957 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING, 0, 0,
1958 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1959 
1960 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_write_queue)) {
1961 				/* This request needs to wait in line to perform RDMA */
1962 				break;
1963 			}
1964 			if ((rqpair->current_send_depth + rdma_req->num_outstanding_data_wr + 1) >
1965 			    rqpair->max_send_depth) {
1966 				/* We can only have so many WRs outstanding. we have to wait until some finish.
1967 				 * +1 since each request has an additional wr in the resp. */
1968 				break;
1969 			}
1970 
1971 			/* We have already verified that this request is the head of the queue. */
1972 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_write_queue, state_link);
1973 
1974 			/* The data transfer will be kicked off from
1975 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
1976 			 */
1977 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1978 			break;
1979 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
1980 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
1981 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1982 			rc = request_transfer_out(&rdma_req->req, &data_posted);
1983 			assert(rc == 0); /* No good way to handle this currently */
1984 			if (rc) {
1985 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1986 			} else {
1987 				rdma_req->state = data_posted ? RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
1988 						  RDMA_REQUEST_STATE_COMPLETING;
1989 			}
1990 			break;
1991 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
1992 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
1993 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1994 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
1995 			 * to escape this state. */
1996 			break;
1997 		case RDMA_REQUEST_STATE_COMPLETING:
1998 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
1999 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2000 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2001 			 * to escape this state. */
2002 			break;
2003 		case RDMA_REQUEST_STATE_COMPLETED:
2004 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
2005 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2006 
2007 			nvmf_rdma_request_free(rdma_req, rtransport);
2008 			break;
2009 		case RDMA_REQUEST_NUM_STATES:
2010 		default:
2011 			assert(0);
2012 			break;
2013 		}
2014 
2015 		if (rdma_req->state != prev_state) {
2016 			progress = true;
2017 		}
2018 	} while (rdma_req->state != prev_state);
2019 
2020 	return progress;
2021 }
2022 
2023 /* Public API callbacks begin here */
2024 
2025 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
2026 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
2027 #define SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH 4096
2028 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 64
2029 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2030 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
2031 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
2032 #define SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS 4096
2033 #define SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE 32
2034 
2035 static void
2036 spdk_nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
2037 {
2038 	opts->max_queue_depth =		SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
2039 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2040 	opts->in_capsule_data_size =	SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
2041 	opts->max_io_size =		SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
2042 	opts->io_unit_size =		SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE;
2043 	opts->max_aq_depth =		SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
2044 	opts->num_shared_buffers =	SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS;
2045 	opts->buf_cache_size =		SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE;
2046 	opts->max_srq_depth =		SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH;
2047 }
2048 
2049 const struct spdk_mem_map_ops g_nvmf_rdma_map_ops = {
2050 	.notify_cb = spdk_nvmf_rdma_mem_notify,
2051 	.are_contiguous = spdk_nvmf_rdma_check_contiguous_entries
2052 };
2053 
2054 static int spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport);
2055 
2056 static struct spdk_nvmf_transport *
2057 spdk_nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
2058 {
2059 	int rc;
2060 	struct spdk_nvmf_rdma_transport *rtransport;
2061 	struct spdk_nvmf_rdma_device	*device, *tmp;
2062 	struct ibv_pd			*pd;
2063 	struct ibv_context		**contexts;
2064 	uint32_t			i;
2065 	int				flag;
2066 	uint32_t			sge_count;
2067 	uint32_t			min_shared_buffers;
2068 	int				max_device_sge = SPDK_NVMF_MAX_SGL_ENTRIES;
2069 
2070 	rtransport = calloc(1, sizeof(*rtransport));
2071 	if (!rtransport) {
2072 		return NULL;
2073 	}
2074 
2075 	if (pthread_mutex_init(&rtransport->lock, NULL)) {
2076 		SPDK_ERRLOG("pthread_mutex_init() failed\n");
2077 		free(rtransport);
2078 		return NULL;
2079 	}
2080 
2081 	TAILQ_INIT(&rtransport->devices);
2082 	TAILQ_INIT(&rtransport->ports);
2083 
2084 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
2085 
2086 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** RDMA Transport Init ***\n"
2087 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
2088 		     "  max_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
2089 		     "  in_capsule_data_size=%d, max_aq_depth=%d,\n"
2090 		     "  num_shared_buffers=%d, max_srq_depth=%d\n",
2091 		     opts->max_queue_depth,
2092 		     opts->max_io_size,
2093 		     opts->max_qpairs_per_ctrlr,
2094 		     opts->io_unit_size,
2095 		     opts->in_capsule_data_size,
2096 		     opts->max_aq_depth,
2097 		     opts->num_shared_buffers,
2098 		     opts->max_srq_depth);
2099 
2100 	/* I/O unit size cannot be larger than max I/O size */
2101 	if (opts->io_unit_size > opts->max_io_size) {
2102 		opts->io_unit_size = opts->max_io_size;
2103 	}
2104 
2105 	if (opts->num_shared_buffers < (SPDK_NVMF_MAX_SGL_ENTRIES * 2)) {
2106 		SPDK_ERRLOG("The number of shared data buffers (%d) is less than"
2107 			    "the minimum number required to guarantee that forward progress can be made (%d)\n",
2108 			    opts->num_shared_buffers, (SPDK_NVMF_MAX_SGL_ENTRIES * 2));
2109 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2110 		return NULL;
2111 	}
2112 
2113 	min_shared_buffers = spdk_thread_get_count() * opts->buf_cache_size;
2114 	if (min_shared_buffers > opts->num_shared_buffers) {
2115 		SPDK_ERRLOG("There are not enough buffers to satisfy"
2116 			    "per-poll group caches for each thread. (%" PRIu32 ")"
2117 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
2118 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
2119 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2120 		return NULL;
2121 	}
2122 
2123 	sge_count = opts->max_io_size / opts->io_unit_size;
2124 	if (sge_count > NVMF_DEFAULT_TX_SGE) {
2125 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
2126 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2127 		return NULL;
2128 	}
2129 
2130 	rtransport->event_channel = rdma_create_event_channel();
2131 	if (rtransport->event_channel == NULL) {
2132 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
2133 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2134 		return NULL;
2135 	}
2136 
2137 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
2138 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2139 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
2140 			    rtransport->event_channel->fd, spdk_strerror(errno));
2141 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2142 		return NULL;
2143 	}
2144 
2145 	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data",
2146 				   opts->max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES,
2147 				   sizeof(struct spdk_nvmf_rdma_request_data),
2148 				   SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
2149 				   SPDK_ENV_SOCKET_ID_ANY);
2150 	if (!rtransport->data_wr_pool) {
2151 		SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");
2152 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2153 		return NULL;
2154 	}
2155 
2156 	contexts = rdma_get_devices(NULL);
2157 	if (contexts == NULL) {
2158 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2159 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2160 		return NULL;
2161 	}
2162 
2163 	i = 0;
2164 	rc = 0;
2165 	while (contexts[i] != NULL) {
2166 		device = calloc(1, sizeof(*device));
2167 		if (!device) {
2168 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
2169 			rc = -ENOMEM;
2170 			break;
2171 		}
2172 		device->context = contexts[i];
2173 		rc = ibv_query_device(device->context, &device->attr);
2174 		if (rc < 0) {
2175 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2176 			free(device);
2177 			break;
2178 
2179 		}
2180 
2181 		max_device_sge = spdk_min(max_device_sge, device->attr.max_sge);
2182 
2183 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2184 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
2185 			SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
2186 			SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
2187 		}
2188 
2189 		/**
2190 		 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
2191 		 * The Soft-RoCE RXE driver does not currently support send with invalidate,
2192 		 * but incorrectly reports that it does. There are changes making their way
2193 		 * through the kernel now that will enable this feature. When they are merged,
2194 		 * we can conditionally enable this feature.
2195 		 *
2196 		 * TODO: enable this for versions of the kernel rxe driver that support it.
2197 		 */
2198 		if (device->attr.vendor_id == 0) {
2199 			device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
2200 		}
2201 #endif
2202 
2203 		/* set up device context async ev fd as NON_BLOCKING */
2204 		flag = fcntl(device->context->async_fd, F_GETFL);
2205 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
2206 		if (rc < 0) {
2207 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
2208 			free(device);
2209 			break;
2210 		}
2211 
2212 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
2213 		i++;
2214 
2215 		pd = NULL;
2216 		if (g_nvmf_hooks.get_ibv_pd) {
2217 			pd = g_nvmf_hooks.get_ibv_pd(NULL, device->context);
2218 		}
2219 
2220 		if (!g_nvmf_hooks.get_ibv_pd) {
2221 			device->pd = ibv_alloc_pd(device->context);
2222 			if (!device->pd) {
2223 				SPDK_ERRLOG("Unable to allocate protection domain.\n");
2224 				spdk_nvmf_rdma_destroy(&rtransport->transport);
2225 				return NULL;
2226 			}
2227 		} else {
2228 			device->pd = pd;
2229 		}
2230 
2231 		assert(device->map == NULL);
2232 
2233 		device->map = spdk_mem_map_alloc(0, &g_nvmf_rdma_map_ops, device->pd);
2234 		if (!device->map) {
2235 			SPDK_ERRLOG("Unable to allocate memory map for listen address\n");
2236 			spdk_nvmf_rdma_destroy(&rtransport->transport);
2237 			return NULL;
2238 		}
2239 
2240 		assert(device->map != NULL);
2241 		assert(device->pd != NULL);
2242 	}
2243 	rdma_free_devices(contexts);
2244 
2245 	if (opts->io_unit_size * max_device_sge < opts->max_io_size) {
2246 		/* divide and round up. */
2247 		opts->io_unit_size = (opts->max_io_size + max_device_sge - 1) / max_device_sge;
2248 
2249 		/* round up to the nearest 4k. */
2250 		opts->io_unit_size = (opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT - 1) & ~NVMF_DATA_BUFFER_MASK;
2251 
2252 		opts->io_unit_size = spdk_max(opts->io_unit_size, SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
2253 		SPDK_NOTICELOG("Adjusting the io unit size to fit the device's maximum I/O size. New I/O unit size %u\n",
2254 			       opts->io_unit_size);
2255 	}
2256 
2257 	if (rc < 0) {
2258 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2259 		return NULL;
2260 	}
2261 
2262 	/* Set up poll descriptor array to monitor events from RDMA and IB
2263 	 * in a single poll syscall
2264 	 */
2265 	rtransport->npoll_fds = i + 1;
2266 	i = 0;
2267 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
2268 	if (rtransport->poll_fds == NULL) {
2269 		SPDK_ERRLOG("poll_fds allocation failed\n");
2270 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2271 		return NULL;
2272 	}
2273 
2274 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
2275 	rtransport->poll_fds[i++].events = POLLIN;
2276 
2277 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2278 		rtransport->poll_fds[i].fd = device->context->async_fd;
2279 		rtransport->poll_fds[i++].events = POLLIN;
2280 	}
2281 
2282 	return &rtransport->transport;
2283 }
2284 
2285 static int
2286 spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport)
2287 {
2288 	struct spdk_nvmf_rdma_transport	*rtransport;
2289 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
2290 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
2291 
2292 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2293 
2294 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
2295 		TAILQ_REMOVE(&rtransport->ports, port, link);
2296 		rdma_destroy_id(port->id);
2297 		free(port);
2298 	}
2299 
2300 	if (rtransport->poll_fds != NULL) {
2301 		free(rtransport->poll_fds);
2302 	}
2303 
2304 	if (rtransport->event_channel != NULL) {
2305 		rdma_destroy_event_channel(rtransport->event_channel);
2306 	}
2307 
2308 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
2309 		TAILQ_REMOVE(&rtransport->devices, device, link);
2310 		if (device->map) {
2311 			spdk_mem_map_free(&device->map);
2312 		}
2313 		if (device->pd) {
2314 			if (!g_nvmf_hooks.get_ibv_pd) {
2315 				ibv_dealloc_pd(device->pd);
2316 			}
2317 		}
2318 		free(device);
2319 	}
2320 
2321 	if (rtransport->data_wr_pool != NULL) {
2322 		if (spdk_mempool_count(rtransport->data_wr_pool) !=
2323 		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {
2324 			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",
2325 				    spdk_mempool_count(rtransport->data_wr_pool),
2326 				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);
2327 		}
2328 	}
2329 
2330 	spdk_mempool_free(rtransport->data_wr_pool);
2331 	pthread_mutex_destroy(&rtransport->lock);
2332 	free(rtransport);
2333 
2334 	return 0;
2335 }
2336 
2337 static int
2338 spdk_nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2339 			       struct spdk_nvme_transport_id *trid,
2340 			       bool peer);
2341 
2342 static int
2343 spdk_nvmf_rdma_listen(struct spdk_nvmf_transport *transport,
2344 		      const struct spdk_nvme_transport_id *trid)
2345 {
2346 	struct spdk_nvmf_rdma_transport	*rtransport;
2347 	struct spdk_nvmf_rdma_device	*device;
2348 	struct spdk_nvmf_rdma_port	*port_tmp, *port;
2349 	struct addrinfo			*res;
2350 	struct addrinfo			hints;
2351 	int				family;
2352 	int				rc;
2353 
2354 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2355 
2356 	port = calloc(1, sizeof(*port));
2357 	if (!port) {
2358 		return -ENOMEM;
2359 	}
2360 
2361 	/* Selectively copy the trid. Things like NQN don't matter here - that
2362 	 * mapping is enforced elsewhere.
2363 	 */
2364 	port->trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
2365 	port->trid.adrfam = trid->adrfam;
2366 	snprintf(port->trid.traddr, sizeof(port->trid.traddr), "%s", trid->traddr);
2367 	snprintf(port->trid.trsvcid, sizeof(port->trid.trsvcid), "%s", trid->trsvcid);
2368 
2369 	pthread_mutex_lock(&rtransport->lock);
2370 	assert(rtransport->event_channel != NULL);
2371 	TAILQ_FOREACH(port_tmp, &rtransport->ports, link) {
2372 		if (spdk_nvme_transport_id_compare(&port_tmp->trid, &port->trid) == 0) {
2373 			port_tmp->ref++;
2374 			free(port);
2375 			/* Already listening at this address */
2376 			pthread_mutex_unlock(&rtransport->lock);
2377 			return 0;
2378 		}
2379 	}
2380 
2381 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
2382 	if (rc < 0) {
2383 		SPDK_ERRLOG("rdma_create_id() failed\n");
2384 		free(port);
2385 		pthread_mutex_unlock(&rtransport->lock);
2386 		return rc;
2387 	}
2388 
2389 	switch (port->trid.adrfam) {
2390 	case SPDK_NVMF_ADRFAM_IPV4:
2391 		family = AF_INET;
2392 		break;
2393 	case SPDK_NVMF_ADRFAM_IPV6:
2394 		family = AF_INET6;
2395 		break;
2396 	default:
2397 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", port->trid.adrfam);
2398 		free(port);
2399 		pthread_mutex_unlock(&rtransport->lock);
2400 		return -EINVAL;
2401 	}
2402 
2403 	memset(&hints, 0, sizeof(hints));
2404 	hints.ai_family = family;
2405 	hints.ai_flags = AI_NUMERICSERV;
2406 	hints.ai_socktype = SOCK_STREAM;
2407 	hints.ai_protocol = 0;
2408 
2409 	rc = getaddrinfo(port->trid.traddr, port->trid.trsvcid, &hints, &res);
2410 	if (rc) {
2411 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
2412 		free(port);
2413 		pthread_mutex_unlock(&rtransport->lock);
2414 		return -EINVAL;
2415 	}
2416 
2417 	rc = rdma_bind_addr(port->id, res->ai_addr);
2418 	freeaddrinfo(res);
2419 
2420 	if (rc < 0) {
2421 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
2422 		rdma_destroy_id(port->id);
2423 		free(port);
2424 		pthread_mutex_unlock(&rtransport->lock);
2425 		return rc;
2426 	}
2427 
2428 	if (!port->id->verbs) {
2429 		SPDK_ERRLOG("ibv_context is null\n");
2430 		rdma_destroy_id(port->id);
2431 		free(port);
2432 		pthread_mutex_unlock(&rtransport->lock);
2433 		return -1;
2434 	}
2435 
2436 	rc = rdma_listen(port->id, 10); /* 10 = backlog */
2437 	if (rc < 0) {
2438 		SPDK_ERRLOG("rdma_listen() failed\n");
2439 		rdma_destroy_id(port->id);
2440 		free(port);
2441 		pthread_mutex_unlock(&rtransport->lock);
2442 		return rc;
2443 	}
2444 
2445 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2446 		if (device->context == port->id->verbs) {
2447 			port->device = device;
2448 			break;
2449 		}
2450 	}
2451 	if (!port->device) {
2452 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
2453 			    port->id->verbs);
2454 		rdma_destroy_id(port->id);
2455 		free(port);
2456 		pthread_mutex_unlock(&rtransport->lock);
2457 		return -EINVAL;
2458 	}
2459 
2460 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** NVMf Target Listening on %s port %d ***\n",
2461 		     port->trid.traddr, ntohs(rdma_get_src_port(port->id)));
2462 
2463 	port->ref = 1;
2464 
2465 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
2466 	pthread_mutex_unlock(&rtransport->lock);
2467 
2468 	return 0;
2469 }
2470 
2471 static int
2472 spdk_nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
2473 			   const struct spdk_nvme_transport_id *_trid)
2474 {
2475 	struct spdk_nvmf_rdma_transport *rtransport;
2476 	struct spdk_nvmf_rdma_port *port, *tmp;
2477 	struct spdk_nvme_transport_id trid = {};
2478 
2479 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2480 
2481 	/* Selectively copy the trid. Things like NQN don't matter here - that
2482 	 * mapping is enforced elsewhere.
2483 	 */
2484 	trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
2485 	trid.adrfam = _trid->adrfam;
2486 	snprintf(trid.traddr, sizeof(port->trid.traddr), "%s", _trid->traddr);
2487 	snprintf(trid.trsvcid, sizeof(port->trid.trsvcid), "%s", _trid->trsvcid);
2488 
2489 	pthread_mutex_lock(&rtransport->lock);
2490 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
2491 		if (spdk_nvme_transport_id_compare(&port->trid, &trid) == 0) {
2492 			assert(port->ref > 0);
2493 			port->ref--;
2494 			if (port->ref == 0) {
2495 				TAILQ_REMOVE(&rtransport->ports, port, link);
2496 				rdma_destroy_id(port->id);
2497 				free(port);
2498 			}
2499 			break;
2500 		}
2501 	}
2502 
2503 	pthread_mutex_unlock(&rtransport->lock);
2504 	return 0;
2505 }
2506 
2507 static void
2508 spdk_nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
2509 				     struct spdk_nvmf_rdma_qpair *rqpair, bool drain)
2510 {
2511 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
2512 	struct spdk_nvmf_rdma_resources *resources;
2513 
2514 	/* We process I/O in the data transfer pending queue at the highest priority. RDMA reads first */
2515 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_read_queue, state_link, req_tmp) {
2516 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2517 			break;
2518 		}
2519 	}
2520 
2521 	/* Then RDMA writes since reads have stronger restrictions than writes */
2522 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_write_queue, state_link, req_tmp) {
2523 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2524 			break;
2525 		}
2526 	}
2527 
2528 	/* The second highest priority is I/O waiting on memory buffers. */
2529 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->poller->group->pending_data_buf_queue, link,
2530 			   req_tmp) {
2531 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2532 			break;
2533 		}
2534 	}
2535 
2536 	resources = rqpair->resources;
2537 	while (!STAILQ_EMPTY(&resources->free_queue) && !STAILQ_EMPTY(&resources->incoming_queue)) {
2538 		rdma_req = STAILQ_FIRST(&resources->free_queue);
2539 		STAILQ_REMOVE_HEAD(&resources->free_queue, state_link);
2540 		rdma_req->recv = STAILQ_FIRST(&resources->incoming_queue);
2541 		STAILQ_REMOVE_HEAD(&resources->incoming_queue, link);
2542 
2543 		if (rqpair->srq != NULL) {
2544 			rdma_req->req.qpair = &rdma_req->recv->qpair->qpair;
2545 			rdma_req->recv->qpair->qd++;
2546 		} else {
2547 			rqpair->qd++;
2548 		}
2549 
2550 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
2551 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false) {
2552 			break;
2553 		}
2554 	}
2555 }
2556 
2557 static void
2558 _nvmf_rdma_qpair_disconnect(void *ctx)
2559 {
2560 	struct spdk_nvmf_qpair *qpair = ctx;
2561 
2562 	spdk_nvmf_qpair_disconnect(qpair, NULL, NULL);
2563 }
2564 
2565 static void
2566 _nvmf_rdma_try_disconnect(void *ctx)
2567 {
2568 	struct spdk_nvmf_qpair *qpair = ctx;
2569 	struct spdk_nvmf_poll_group *group;
2570 
2571 	/* Read the group out of the qpair. This is normally set and accessed only from
2572 	 * the thread that created the group. Here, we're not on that thread necessarily.
2573 	 * The data member qpair->group begins it's life as NULL and then is assigned to
2574 	 * a pointer and never changes. So fortunately reading this and checking for
2575 	 * non-NULL is thread safe in the x86_64 memory model. */
2576 	group = qpair->group;
2577 
2578 	if (group == NULL) {
2579 		/* The qpair hasn't been assigned to a group yet, so we can't
2580 		 * process a disconnect. Send a message to ourself and try again. */
2581 		spdk_thread_send_msg(spdk_get_thread(), _nvmf_rdma_try_disconnect, qpair);
2582 		return;
2583 	}
2584 
2585 	spdk_thread_send_msg(group->thread, _nvmf_rdma_qpair_disconnect, qpair);
2586 }
2587 
2588 static inline void
2589 spdk_nvmf_rdma_start_disconnect(struct spdk_nvmf_rdma_qpair *rqpair)
2590 {
2591 	if (__sync_bool_compare_and_swap(&rqpair->disconnect_started, false, true)) {
2592 		_nvmf_rdma_try_disconnect(&rqpair->qpair);
2593 	}
2594 }
2595 
2596 static void nvmf_rdma_destroy_drained_qpair(void *ctx)
2597 {
2598 	struct spdk_nvmf_rdma_qpair *rqpair = ctx;
2599 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
2600 			struct spdk_nvmf_rdma_transport, transport);
2601 
2602 	/* In non SRQ path, we will reach rqpair->max_queue_depth. In SRQ path, we will get the last_wqe event. */
2603 	if (rqpair->current_send_depth != 0) {
2604 		return;
2605 	}
2606 
2607 	if (rqpair->srq == NULL && rqpair->current_recv_depth != rqpair->max_queue_depth) {
2608 		return;
2609 	}
2610 
2611 	if (rqpair->srq != NULL && rqpair->last_wqe_reached == false) {
2612 		return;
2613 	}
2614 
2615 	spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
2616 	spdk_nvmf_rdma_qpair_destroy(rqpair);
2617 }
2618 
2619 
2620 static int
2621 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
2622 {
2623 	struct spdk_nvmf_qpair		*qpair;
2624 	struct spdk_nvmf_rdma_qpair	*rqpair;
2625 
2626 	if (evt->id == NULL) {
2627 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
2628 		return -1;
2629 	}
2630 
2631 	qpair = evt->id->context;
2632 	if (qpair == NULL) {
2633 		SPDK_ERRLOG("disconnect request: no active connection\n");
2634 		return -1;
2635 	}
2636 
2637 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2638 
2639 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair->cm_id, 0);
2640 
2641 	spdk_nvmf_rdma_update_ibv_state(rqpair);
2642 
2643 	spdk_nvmf_rdma_start_disconnect(rqpair);
2644 
2645 	return 0;
2646 }
2647 
2648 #ifdef DEBUG
2649 static const char *CM_EVENT_STR[] = {
2650 	"RDMA_CM_EVENT_ADDR_RESOLVED",
2651 	"RDMA_CM_EVENT_ADDR_ERROR",
2652 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
2653 	"RDMA_CM_EVENT_ROUTE_ERROR",
2654 	"RDMA_CM_EVENT_CONNECT_REQUEST",
2655 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
2656 	"RDMA_CM_EVENT_CONNECT_ERROR",
2657 	"RDMA_CM_EVENT_UNREACHABLE",
2658 	"RDMA_CM_EVENT_REJECTED",
2659 	"RDMA_CM_EVENT_ESTABLISHED",
2660 	"RDMA_CM_EVENT_DISCONNECTED",
2661 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
2662 	"RDMA_CM_EVENT_MULTICAST_JOIN",
2663 	"RDMA_CM_EVENT_MULTICAST_ERROR",
2664 	"RDMA_CM_EVENT_ADDR_CHANGE",
2665 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
2666 };
2667 #endif /* DEBUG */
2668 
2669 static void
2670 spdk_nvmf_process_cm_event(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
2671 {
2672 	struct spdk_nvmf_rdma_transport *rtransport;
2673 	struct rdma_cm_event		*event;
2674 	int				rc;
2675 
2676 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2677 
2678 	if (rtransport->event_channel == NULL) {
2679 		return;
2680 	}
2681 
2682 	while (1) {
2683 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
2684 		if (rc == 0) {
2685 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
2686 
2687 			spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
2688 
2689 			switch (event->event) {
2690 			case RDMA_CM_EVENT_ADDR_RESOLVED:
2691 			case RDMA_CM_EVENT_ADDR_ERROR:
2692 			case RDMA_CM_EVENT_ROUTE_RESOLVED:
2693 			case RDMA_CM_EVENT_ROUTE_ERROR:
2694 				/* No action required. The target never attempts to resolve routes. */
2695 				break;
2696 			case RDMA_CM_EVENT_CONNECT_REQUEST:
2697 				rc = nvmf_rdma_connect(transport, event, cb_fn);
2698 				if (rc < 0) {
2699 					SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
2700 					break;
2701 				}
2702 				break;
2703 			case RDMA_CM_EVENT_CONNECT_RESPONSE:
2704 				/* The target never initiates a new connection. So this will not occur. */
2705 				break;
2706 			case RDMA_CM_EVENT_CONNECT_ERROR:
2707 				/* Can this happen? The docs say it can, but not sure what causes it. */
2708 				break;
2709 			case RDMA_CM_EVENT_UNREACHABLE:
2710 			case RDMA_CM_EVENT_REJECTED:
2711 				/* These only occur on the client side. */
2712 				break;
2713 			case RDMA_CM_EVENT_ESTABLISHED:
2714 				/* TODO: Should we be waiting for this event anywhere? */
2715 				break;
2716 			case RDMA_CM_EVENT_DISCONNECTED:
2717 			case RDMA_CM_EVENT_DEVICE_REMOVAL:
2718 				rc = nvmf_rdma_disconnect(event);
2719 				if (rc < 0) {
2720 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2721 					break;
2722 				}
2723 				break;
2724 			case RDMA_CM_EVENT_MULTICAST_JOIN:
2725 			case RDMA_CM_EVENT_MULTICAST_ERROR:
2726 				/* Multicast is not used */
2727 				break;
2728 			case RDMA_CM_EVENT_ADDR_CHANGE:
2729 				/* Not utilizing this event */
2730 				break;
2731 			case RDMA_CM_EVENT_TIMEWAIT_EXIT:
2732 				/* For now, do nothing. The target never re-uses queue pairs. */
2733 				break;
2734 			default:
2735 				SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
2736 				break;
2737 			}
2738 
2739 			rdma_ack_cm_event(event);
2740 		} else {
2741 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
2742 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
2743 			}
2744 			break;
2745 		}
2746 	}
2747 }
2748 
2749 static void
2750 spdk_nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
2751 {
2752 	int				rc;
2753 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
2754 	struct ibv_async_event		event;
2755 	enum ibv_qp_state		state;
2756 
2757 	rc = ibv_get_async_event(device->context, &event);
2758 
2759 	if (rc) {
2760 		SPDK_ERRLOG("Failed to get async_event (%d): %s\n",
2761 			    errno, spdk_strerror(errno));
2762 		return;
2763 	}
2764 
2765 	SPDK_NOTICELOG("Async event: %s\n",
2766 		       ibv_event_type_str(event.event_type));
2767 
2768 	switch (event.event_type) {
2769 	case IBV_EVENT_QP_FATAL:
2770 		rqpair = event.element.qp->qp_context;
2771 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
2772 				  (uintptr_t)rqpair->cm_id, event.event_type);
2773 		spdk_nvmf_rdma_update_ibv_state(rqpair);
2774 		spdk_nvmf_rdma_start_disconnect(rqpair);
2775 		break;
2776 	case IBV_EVENT_QP_LAST_WQE_REACHED:
2777 		/* This event only occurs for shared receive queues. */
2778 		rqpair = event.element.qp->qp_context;
2779 		rqpair->last_wqe_reached = true;
2780 
2781 		/* This must be handled on the polling thread if it exists. Otherwise the timeout will catch it. */
2782 		if (rqpair->qpair.group) {
2783 			spdk_thread_send_msg(rqpair->qpair.group->thread, nvmf_rdma_destroy_drained_qpair, rqpair);
2784 		} else {
2785 			SPDK_ERRLOG("Unable to destroy the qpair %p since it does not have a poll group.\n", rqpair);
2786 		}
2787 
2788 		break;
2789 	case IBV_EVENT_SQ_DRAINED:
2790 		/* This event occurs frequently in both error and non-error states.
2791 		 * Check if the qpair is in an error state before sending a message.
2792 		 * Note that we're not on the correct thread to access the qpair, but
2793 		 * the operations that the below calls make all happen to be thread
2794 		 * safe. */
2795 		rqpair = event.element.qp->qp_context;
2796 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
2797 				  (uintptr_t)rqpair->cm_id, event.event_type);
2798 		state = spdk_nvmf_rdma_update_ibv_state(rqpair);
2799 		if (state == IBV_QPS_ERR) {
2800 			spdk_nvmf_rdma_start_disconnect(rqpair);
2801 		}
2802 		break;
2803 	case IBV_EVENT_QP_REQ_ERR:
2804 	case IBV_EVENT_QP_ACCESS_ERR:
2805 	case IBV_EVENT_COMM_EST:
2806 	case IBV_EVENT_PATH_MIG:
2807 	case IBV_EVENT_PATH_MIG_ERR:
2808 		rqpair = event.element.qp->qp_context;
2809 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
2810 				  (uintptr_t)rqpair->cm_id, event.event_type);
2811 		spdk_nvmf_rdma_update_ibv_state(rqpair);
2812 		break;
2813 	case IBV_EVENT_CQ_ERR:
2814 	case IBV_EVENT_DEVICE_FATAL:
2815 	case IBV_EVENT_PORT_ACTIVE:
2816 	case IBV_EVENT_PORT_ERR:
2817 	case IBV_EVENT_LID_CHANGE:
2818 	case IBV_EVENT_PKEY_CHANGE:
2819 	case IBV_EVENT_SM_CHANGE:
2820 	case IBV_EVENT_SRQ_ERR:
2821 	case IBV_EVENT_SRQ_LIMIT_REACHED:
2822 	case IBV_EVENT_CLIENT_REREGISTER:
2823 	case IBV_EVENT_GID_CHANGE:
2824 	default:
2825 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
2826 		break;
2827 	}
2828 	ibv_ack_async_event(&event);
2829 }
2830 
2831 static void
2832 spdk_nvmf_rdma_accept(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
2833 {
2834 	int	nfds, i = 0;
2835 	struct spdk_nvmf_rdma_transport *rtransport;
2836 	struct spdk_nvmf_rdma_device *device, *tmp;
2837 
2838 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2839 	nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
2840 
2841 	if (nfds <= 0) {
2842 		return;
2843 	}
2844 
2845 	/* The first poll descriptor is RDMA CM event */
2846 	if (rtransport->poll_fds[i++].revents & POLLIN) {
2847 		spdk_nvmf_process_cm_event(transport, cb_fn);
2848 		nfds--;
2849 	}
2850 
2851 	if (nfds == 0) {
2852 		return;
2853 	}
2854 
2855 	/* Second and subsequent poll descriptors are IB async events */
2856 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2857 		if (rtransport->poll_fds[i++].revents & POLLIN) {
2858 			spdk_nvmf_process_ib_event(device);
2859 			nfds--;
2860 		}
2861 	}
2862 	/* check all flagged fd's have been served */
2863 	assert(nfds == 0);
2864 }
2865 
2866 static void
2867 spdk_nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
2868 			struct spdk_nvme_transport_id *trid,
2869 			struct spdk_nvmf_discovery_log_page_entry *entry)
2870 {
2871 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
2872 	entry->adrfam = trid->adrfam;
2873 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_SPECIFIED;
2874 
2875 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
2876 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
2877 
2878 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
2879 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
2880 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
2881 }
2882 
2883 static void
2884 spdk_nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
2885 
2886 static struct spdk_nvmf_transport_poll_group *
2887 spdk_nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
2888 {
2889 	struct spdk_nvmf_rdma_transport		*rtransport;
2890 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2891 	struct spdk_nvmf_rdma_poller		*poller;
2892 	struct spdk_nvmf_rdma_device		*device;
2893 	struct ibv_srq_init_attr		srq_init_attr;
2894 	struct spdk_nvmf_rdma_resource_opts	opts;
2895 	int					num_cqe;
2896 
2897 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2898 
2899 	rgroup = calloc(1, sizeof(*rgroup));
2900 	if (!rgroup) {
2901 		return NULL;
2902 	}
2903 
2904 	TAILQ_INIT(&rgroup->pollers);
2905 	TAILQ_INIT(&rgroup->pending_data_buf_queue);
2906 
2907 	pthread_mutex_lock(&rtransport->lock);
2908 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2909 		poller = calloc(1, sizeof(*poller));
2910 		if (!poller) {
2911 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
2912 			spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
2913 			pthread_mutex_unlock(&rtransport->lock);
2914 			return NULL;
2915 		}
2916 
2917 		poller->device = device;
2918 		poller->group = rgroup;
2919 
2920 		TAILQ_INIT(&poller->qpairs);
2921 
2922 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
2923 		if (device->attr.max_srq != 0) {
2924 			poller->max_srq_depth = transport->opts.max_srq_depth;
2925 
2926 			memset(&srq_init_attr, 0, sizeof(struct ibv_srq_init_attr));
2927 			srq_init_attr.attr.max_wr = poller->max_srq_depth;
2928 			srq_init_attr.attr.max_sge = spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
2929 			poller->srq = ibv_create_srq(device->pd, &srq_init_attr);
2930 			if (!poller->srq) {
2931 				SPDK_ERRLOG("Unable to create shared receive queue, errno %d\n", errno);
2932 				spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
2933 				pthread_mutex_unlock(&rtransport->lock);
2934 				return NULL;
2935 			}
2936 
2937 			opts.qp = poller->srq;
2938 			opts.pd = device->pd;
2939 			opts.qpair = NULL;
2940 			opts.shared = true;
2941 			opts.max_queue_depth = poller->max_srq_depth;
2942 			opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
2943 
2944 			poller->resources = nvmf_rdma_resources_create(&opts);
2945 			if (!poller->resources) {
2946 				SPDK_ERRLOG("Unable to allocate resources for shared receive queue.\n");
2947 				spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
2948 				pthread_mutex_unlock(&rtransport->lock);
2949 			}
2950 		}
2951 
2952 		/*
2953 		 * When using an srq, we can limit the completion queue at startup.
2954 		 * The following formula represents the calculation:
2955 		 * num_cqe = num_recv + num_data_wr + num_send_wr.
2956 		 * where num_recv=num_data_wr=and num_send_wr=poller->max_srq_depth
2957 		 */
2958 		if (poller->srq) {
2959 			num_cqe = poller->max_srq_depth * 3;
2960 		} else {
2961 			num_cqe = DEFAULT_NVMF_RDMA_CQ_SIZE;
2962 		}
2963 
2964 		poller->cq = ibv_create_cq(device->context, num_cqe, poller, NULL, 0);
2965 		if (!poller->cq) {
2966 			SPDK_ERRLOG("Unable to create completion queue\n");
2967 			spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
2968 			pthread_mutex_unlock(&rtransport->lock);
2969 			return NULL;
2970 		}
2971 		poller->num_cqe = num_cqe;
2972 	}
2973 
2974 	pthread_mutex_unlock(&rtransport->lock);
2975 	return &rgroup->group;
2976 }
2977 
2978 static void
2979 spdk_nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
2980 {
2981 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2982 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
2983 	struct spdk_nvmf_rdma_qpair		*qpair, *tmp_qpair;
2984 
2985 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
2986 
2987 	if (!rgroup) {
2988 		return;
2989 	}
2990 
2991 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
2992 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
2993 
2994 		TAILQ_FOREACH_SAFE(qpair, &poller->qpairs, link, tmp_qpair) {
2995 			spdk_nvmf_rdma_qpair_destroy(qpair);
2996 		}
2997 
2998 		if (poller->srq) {
2999 			nvmf_rdma_resources_destroy(poller->resources);
3000 			ibv_destroy_srq(poller->srq);
3001 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Destroyed RDMA shared queue %p\n", poller->srq);
3002 		}
3003 
3004 		if (poller->cq) {
3005 			ibv_destroy_cq(poller->cq);
3006 		}
3007 
3008 		free(poller);
3009 	}
3010 
3011 	if (!TAILQ_EMPTY(&rgroup->pending_data_buf_queue)) {
3012 		SPDK_ERRLOG("Pending I/O list wasn't empty on poll group destruction\n");
3013 	}
3014 
3015 	free(rgroup);
3016 }
3017 
3018 static void
3019 spdk_nvmf_rdma_qpair_reject_connection(struct spdk_nvmf_rdma_qpair *rqpair)
3020 {
3021 	spdk_nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
3022 	spdk_nvmf_rdma_qpair_destroy(rqpair);
3023 }
3024 
3025 static int
3026 spdk_nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
3027 			      struct spdk_nvmf_qpair *qpair)
3028 {
3029 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3030 	struct spdk_nvmf_rdma_qpair		*rqpair;
3031 	struct spdk_nvmf_rdma_device		*device;
3032 	struct spdk_nvmf_rdma_poller		*poller;
3033 	int					rc;
3034 
3035 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3036 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3037 
3038 	device = rqpair->port->device;
3039 
3040 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
3041 		if (poller->device == device) {
3042 			break;
3043 		}
3044 	}
3045 
3046 	if (!poller) {
3047 		SPDK_ERRLOG("No poller found for device.\n");
3048 		return -1;
3049 	}
3050 
3051 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
3052 	rqpair->poller = poller;
3053 	rqpair->srq = rqpair->poller->srq;
3054 
3055 	rc = spdk_nvmf_rdma_qpair_initialize(qpair);
3056 	if (rc < 0) {
3057 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
3058 		return -1;
3059 	}
3060 
3061 	rc = spdk_nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
3062 	if (rc) {
3063 		/* Try to reject, but we probably can't */
3064 		spdk_nvmf_rdma_qpair_reject_connection(rqpair);
3065 		return -1;
3066 	}
3067 
3068 	spdk_nvmf_rdma_update_ibv_state(rqpair);
3069 
3070 	return 0;
3071 }
3072 
3073 static int
3074 spdk_nvmf_rdma_request_free(struct spdk_nvmf_request *req)
3075 {
3076 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
3077 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3078 			struct spdk_nvmf_rdma_transport, transport);
3079 
3080 	nvmf_rdma_request_free(rdma_req, rtransport);
3081 	return 0;
3082 }
3083 
3084 static int
3085 spdk_nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
3086 {
3087 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3088 			struct spdk_nvmf_rdma_transport, transport);
3089 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
3090 			struct spdk_nvmf_rdma_request, req);
3091 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3092 			struct spdk_nvmf_rdma_qpair, qpair);
3093 
3094 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3095 		/* The connection is alive, so process the request as normal */
3096 		rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
3097 	} else {
3098 		/* The connection is dead. Move the request directly to the completed state. */
3099 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3100 	}
3101 
3102 	spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3103 
3104 	return 0;
3105 }
3106 
3107 static int
3108 spdk_nvmf_rdma_destroy_defunct_qpair(void *ctx)
3109 {
3110 	struct spdk_nvmf_rdma_qpair	*rqpair = ctx;
3111 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
3112 			struct spdk_nvmf_rdma_transport, transport);
3113 
3114 	spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
3115 	spdk_nvmf_rdma_qpair_destroy(rqpair);
3116 
3117 	return 0;
3118 }
3119 
3120 static void
3121 spdk_nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair)
3122 {
3123 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3124 
3125 	if (rqpair->disconnect_flags & RDMA_QP_DISCONNECTING) {
3126 		return;
3127 	}
3128 
3129 	rqpair->disconnect_flags |= RDMA_QP_DISCONNECTING;
3130 
3131 	/* This happens only when the qpair is disconnected before
3132 	 * it is added to the poll group. Since there is no poll group,
3133 	 * the RDMA qp has not been initialized yet and the RDMA CM
3134 	 * event has not yet been acknowledged, so we need to reject it.
3135 	 */
3136 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
3137 		spdk_nvmf_rdma_qpair_reject_connection(rqpair);
3138 		return;
3139 	}
3140 
3141 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3142 		spdk_nvmf_rdma_set_ibv_state(rqpair, IBV_QPS_ERR);
3143 	}
3144 
3145 	rqpair->destruct_poller = spdk_poller_register(spdk_nvmf_rdma_destroy_defunct_qpair, (void *)rqpair,
3146 				  NVMF_RDMA_QPAIR_DESTROY_TIMEOUT_US);
3147 }
3148 
3149 static struct spdk_nvmf_rdma_qpair *
3150 get_rdma_qpair_from_wc(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_wc *wc)
3151 {
3152 	struct spdk_nvmf_rdma_qpair *rqpair;
3153 	/* @todo: improve QP search */
3154 	TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
3155 		if (wc->qp_num == rqpair->cm_id->qp->qp_num) {
3156 			return rqpair;
3157 		}
3158 	}
3159 	SPDK_ERRLOG("Didn't find QP with qp_num %u\n", wc->qp_num);
3160 	return NULL;
3161 }
3162 
3163 #ifdef DEBUG
3164 static int
3165 spdk_nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
3166 {
3167 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
3168 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
3169 }
3170 #endif
3171 
3172 static int
3173 spdk_nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
3174 			   struct spdk_nvmf_rdma_poller *rpoller)
3175 {
3176 	struct ibv_wc wc[32];
3177 	struct spdk_nvmf_rdma_wr	*rdma_wr;
3178 	struct spdk_nvmf_rdma_request	*rdma_req;
3179 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3180 	struct spdk_nvmf_rdma_qpair	*rqpair;
3181 	int reaped, i;
3182 	int count = 0;
3183 	bool error = false;
3184 
3185 	/* Poll for completing operations. */
3186 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
3187 	if (reaped < 0) {
3188 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
3189 			    errno, spdk_strerror(errno));
3190 		return -1;
3191 	}
3192 
3193 	for (i = 0; i < reaped; i++) {
3194 
3195 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
3196 
3197 		switch (rdma_wr->type) {
3198 		case RDMA_WR_TYPE_SEND:
3199 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3200 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3201 
3202 			if (!wc[i].status) {
3203 				count++;
3204 				assert(wc[i].opcode == IBV_WC_SEND);
3205 				assert(spdk_nvmf_rdma_req_is_completing(rdma_req));
3206 			} else {
3207 				SPDK_ERRLOG("data=%p length=%u\n", rdma_req->req.data, rdma_req->req.length);
3208 			}
3209 
3210 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3211 			rqpair->current_send_depth--;
3212 
3213 			spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3214 			assert(rdma_req->num_outstanding_data_wr == 0);
3215 			break;
3216 		case RDMA_WR_TYPE_RECV:
3217 			/* rdma_recv->qpair will be NULL if using an SRQ.  In that case we have to get the qpair from the wc. */
3218 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3219 			if (rdma_recv->qpair == NULL) {
3220 				rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
3221 			}
3222 			rqpair = rdma_recv->qpair;
3223 
3224 			assert(rqpair != NULL);
3225 			if (!wc[i].status) {
3226 				assert(wc[i].opcode == IBV_WC_RECV);
3227 				if (rqpair->current_recv_depth >= rqpair->max_queue_depth) {
3228 					spdk_nvmf_rdma_start_disconnect(rqpair);
3229 					break;
3230 				}
3231 			}
3232 
3233 			rqpair->current_recv_depth++;
3234 			STAILQ_INSERT_TAIL(&rqpair->resources->incoming_queue, rdma_recv, link);
3235 			break;
3236 		case RDMA_WR_TYPE_DATA:
3237 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3238 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3239 
3240 			assert(rdma_req->num_outstanding_data_wr > 0);
3241 
3242 			rqpair->current_send_depth--;
3243 			rdma_req->num_outstanding_data_wr--;
3244 			if (!wc[i].status) {
3245 				if (wc[i].opcode == IBV_WC_RDMA_READ) {
3246 					rqpair->current_read_depth--;
3247 					/* wait for all outstanding reads associated with the same rdma_req to complete before proceeding. */
3248 					if (rdma_req->num_outstanding_data_wr == 0) {
3249 						rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
3250 						spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3251 					}
3252 				} else {
3253 					assert(wc[i].opcode == IBV_WC_RDMA_WRITE);
3254 				}
3255 			} else {
3256 				/* If the data transfer fails still force the queue into the error state,
3257 				 * if we were performing an RDMA_READ, we need to force the request into a
3258 				 * completed state since it wasn't linked to a send. However, in the RDMA_WRITE
3259 				 * case, we should wait for the SEND to complete. */
3260 				SPDK_ERRLOG("data=%p length=%u\n", rdma_req->req.data, rdma_req->req.length);
3261 				if (rdma_req->data.wr.opcode == IBV_WR_RDMA_READ) {
3262 					rqpair->current_read_depth--;
3263 					if (rdma_req->num_outstanding_data_wr == 0) {
3264 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3265 					}
3266 				}
3267 			}
3268 			break;
3269 		default:
3270 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
3271 			continue;
3272 		}
3273 
3274 		/* Handle error conditions */
3275 		if (wc[i].status) {
3276 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "CQ error on CQ %p, Request 0x%lu (%d): %s\n",
3277 				      rpoller->cq, wc[i].wr_id, wc[i].status, ibv_wc_status_str(wc[i].status));
3278 
3279 			error = true;
3280 
3281 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3282 				/* Disconnect the connection. */
3283 				spdk_nvmf_rdma_start_disconnect(rqpair);
3284 			} else {
3285 				nvmf_rdma_destroy_drained_qpair(rqpair);
3286 			}
3287 			continue;
3288 		}
3289 
3290 		spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3291 
3292 		if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
3293 			nvmf_rdma_destroy_drained_qpair(rqpair);
3294 		}
3295 	}
3296 
3297 	if (error == true) {
3298 		return -1;
3299 	}
3300 
3301 	return count;
3302 }
3303 
3304 static int
3305 spdk_nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3306 {
3307 	struct spdk_nvmf_rdma_transport *rtransport;
3308 	struct spdk_nvmf_rdma_poll_group *rgroup;
3309 	struct spdk_nvmf_rdma_poller	*rpoller;
3310 	int				count, rc;
3311 
3312 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
3313 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3314 
3315 	count = 0;
3316 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3317 		rc = spdk_nvmf_rdma_poller_poll(rtransport, rpoller);
3318 		if (rc < 0) {
3319 			return rc;
3320 		}
3321 		count += rc;
3322 	}
3323 
3324 	return count;
3325 }
3326 
3327 static int
3328 spdk_nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
3329 			       struct spdk_nvme_transport_id *trid,
3330 			       bool peer)
3331 {
3332 	struct sockaddr *saddr;
3333 	uint16_t port;
3334 
3335 	trid->trtype = SPDK_NVME_TRANSPORT_RDMA;
3336 
3337 	if (peer) {
3338 		saddr = rdma_get_peer_addr(id);
3339 	} else {
3340 		saddr = rdma_get_local_addr(id);
3341 	}
3342 	switch (saddr->sa_family) {
3343 	case AF_INET: {
3344 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
3345 
3346 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3347 		inet_ntop(AF_INET, &saddr_in->sin_addr,
3348 			  trid->traddr, sizeof(trid->traddr));
3349 		if (peer) {
3350 			port = ntohs(rdma_get_dst_port(id));
3351 		} else {
3352 			port = ntohs(rdma_get_src_port(id));
3353 		}
3354 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3355 		break;
3356 	}
3357 	case AF_INET6: {
3358 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
3359 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3360 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
3361 			  trid->traddr, sizeof(trid->traddr));
3362 		if (peer) {
3363 			port = ntohs(rdma_get_dst_port(id));
3364 		} else {
3365 			port = ntohs(rdma_get_src_port(id));
3366 		}
3367 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3368 		break;
3369 	}
3370 	default:
3371 		return -1;
3372 
3373 	}
3374 
3375 	return 0;
3376 }
3377 
3378 static int
3379 spdk_nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
3380 				   struct spdk_nvme_transport_id *trid)
3381 {
3382 	struct spdk_nvmf_rdma_qpair	*rqpair;
3383 
3384 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3385 
3386 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
3387 }
3388 
3389 static int
3390 spdk_nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
3391 				    struct spdk_nvme_transport_id *trid)
3392 {
3393 	struct spdk_nvmf_rdma_qpair	*rqpair;
3394 
3395 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3396 
3397 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
3398 }
3399 
3400 static int
3401 spdk_nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
3402 				     struct spdk_nvme_transport_id *trid)
3403 {
3404 	struct spdk_nvmf_rdma_qpair	*rqpair;
3405 
3406 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3407 
3408 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
3409 }
3410 
3411 void
3412 spdk_nvmf_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
3413 {
3414 	g_nvmf_hooks = *hooks;
3415 }
3416 
3417 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
3418 	.type = SPDK_NVME_TRANSPORT_RDMA,
3419 	.opts_init = spdk_nvmf_rdma_opts_init,
3420 	.create = spdk_nvmf_rdma_create,
3421 	.destroy = spdk_nvmf_rdma_destroy,
3422 
3423 	.listen = spdk_nvmf_rdma_listen,
3424 	.stop_listen = spdk_nvmf_rdma_stop_listen,
3425 	.accept = spdk_nvmf_rdma_accept,
3426 
3427 	.listener_discover = spdk_nvmf_rdma_discover,
3428 
3429 	.poll_group_create = spdk_nvmf_rdma_poll_group_create,
3430 	.poll_group_destroy = spdk_nvmf_rdma_poll_group_destroy,
3431 	.poll_group_add = spdk_nvmf_rdma_poll_group_add,
3432 	.poll_group_poll = spdk_nvmf_rdma_poll_group_poll,
3433 
3434 	.req_free = spdk_nvmf_rdma_request_free,
3435 	.req_complete = spdk_nvmf_rdma_request_complete,
3436 
3437 	.qpair_fini = spdk_nvmf_rdma_close_qpair,
3438 	.qpair_get_peer_trid = spdk_nvmf_rdma_qpair_get_peer_trid,
3439 	.qpair_get_local_trid = spdk_nvmf_rdma_qpair_get_local_trid,
3440 	.qpair_get_listen_trid = spdk_nvmf_rdma_qpair_get_listen_trid,
3441 
3442 };
3443 
3444 SPDK_LOG_REGISTER_COMPONENT("rdma", SPDK_LOG_RDMA)
3445