xref: /spdk/lib/nvmf/rdma.c (revision 8a2527836d387a4c7dcb576cbb33ad605ee28175)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2019 Mellanox Technologies LTD. All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "spdk/stdinc.h"
35 
36 #include <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/thread.h"
45 #include "spdk/nvmf.h"
46 #include "spdk/nvmf_spec.h"
47 #include "spdk/string.h"
48 #include "spdk/trace.h"
49 #include "spdk/util.h"
50 
51 #include "spdk_internal/assert.h"
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", TRACE_RDMA_REQUEST_STATE_NEW,
166 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 1, 1, "cmid:   ");
167 	spdk_trace_register_description("RDMA_REQ_NEED_BUFFER", TRACE_RDMA_REQUEST_STATE_NEED_BUFFER,
168 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
169 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_C2H",
170 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
171 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
172 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_H2C",
173 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
174 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
175 	spdk_trace_register_description("RDMA_REQ_TX_H2C",
176 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
177 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
178 	spdk_trace_register_description("RDMA_REQ_RDY_TO_EXECUTE",
179 					TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE,
180 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
181 	spdk_trace_register_description("RDMA_REQ_EXECUTING",
182 					TRACE_RDMA_REQUEST_STATE_EXECUTING,
183 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
184 	spdk_trace_register_description("RDMA_REQ_EXECUTED",
185 					TRACE_RDMA_REQUEST_STATE_EXECUTED,
186 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
187 	spdk_trace_register_description("RDMA_REQ_RDY_TO_COMPL",
188 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE,
189 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
190 	spdk_trace_register_description("RDMA_REQ_COMPLETING_C2H",
191 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
192 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
193 	spdk_trace_register_description("RDMA_REQ_COMPLETING",
194 					TRACE_RDMA_REQUEST_STATE_COMPLETING,
195 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
196 	spdk_trace_register_description("RDMA_REQ_COMPLETED",
197 					TRACE_RDMA_REQUEST_STATE_COMPLETED,
198 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
199 
200 	spdk_trace_register_description("RDMA_QP_CREATE", TRACE_RDMA_QP_CREATE,
201 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
202 	spdk_trace_register_description("RDMA_IBV_ASYNC_EVENT", TRACE_RDMA_IBV_ASYNC_EVENT,
203 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
204 	spdk_trace_register_description("RDMA_CM_ASYNC_EVENT", TRACE_RDMA_CM_ASYNC_EVENT,
205 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
206 	spdk_trace_register_description("RDMA_QP_STATE_CHANGE", TRACE_RDMA_QP_STATE_CHANGE,
207 					OWNER_NONE, OBJECT_NONE, 0, 1, "state:  ");
208 	spdk_trace_register_description("RDMA_QP_DISCONNECT", TRACE_RDMA_QP_DISCONNECT,
209 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
210 	spdk_trace_register_description("RDMA_QP_DESTROY", TRACE_RDMA_QP_DESTROY,
211 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
212 }
213 
214 enum spdk_nvmf_rdma_wr_type {
215 	RDMA_WR_TYPE_RECV,
216 	RDMA_WR_TYPE_SEND,
217 	RDMA_WR_TYPE_DATA,
218 };
219 
220 struct spdk_nvmf_rdma_wr {
221 	enum spdk_nvmf_rdma_wr_type	type;
222 };
223 
224 /* This structure holds commands as they are received off the wire.
225  * It must be dynamically paired with a full request object
226  * (spdk_nvmf_rdma_request) to service a request. It is separate
227  * from the request because RDMA does not appear to order
228  * completions, so occasionally we'll get a new incoming
229  * command when there aren't any free request objects.
230  */
231 struct spdk_nvmf_rdma_recv {
232 	struct ibv_recv_wr			wr;
233 	struct ibv_sge				sgl[NVMF_DEFAULT_RX_SGE];
234 
235 	struct spdk_nvmf_rdma_qpair		*qpair;
236 
237 	/* In-capsule data buffer */
238 	uint8_t					*buf;
239 
240 	struct spdk_nvmf_rdma_wr		rdma_wr;
241 	uint64_t				receive_tsc;
242 
243 	STAILQ_ENTRY(spdk_nvmf_rdma_recv)	link;
244 };
245 
246 struct spdk_nvmf_rdma_request_data {
247 	struct spdk_nvmf_rdma_wr	rdma_wr;
248 	struct ibv_send_wr		wr;
249 	struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
250 };
251 
252 struct spdk_nvmf_rdma_request {
253 	struct spdk_nvmf_request		req;
254 
255 	enum spdk_nvmf_rdma_request_state	state;
256 
257 	struct spdk_nvmf_rdma_recv		*recv;
258 
259 	struct {
260 		struct spdk_nvmf_rdma_wr	rdma_wr;
261 		struct	ibv_send_wr		wr;
262 		struct	ibv_sge			sgl[NVMF_DEFAULT_RSP_SGE];
263 	} rsp;
264 
265 	struct spdk_nvmf_rdma_request_data	data;
266 
267 	uint32_t				num_outstanding_data_wr;
268 	uint64_t				receive_tsc;
269 
270 	struct spdk_dif_ctx			dif_ctx;
271 	bool					dif_insert_or_strip;
272 	uint32_t				elba_length;
273 	uint32_t				orig_length;
274 
275 	STAILQ_ENTRY(spdk_nvmf_rdma_request)	state_link;
276 };
277 
278 enum spdk_nvmf_rdma_qpair_disconnect_flags {
279 	RDMA_QP_DISCONNECTING		= 1,
280 	RDMA_QP_RECV_DRAINED		= 1 << 1,
281 	RDMA_QP_SEND_DRAINED		= 1 << 2
282 };
283 
284 struct spdk_nvmf_rdma_resource_opts {
285 	struct spdk_nvmf_rdma_qpair	*qpair;
286 	/* qp points either to an ibv_qp object or an ibv_srq object depending on the value of shared. */
287 	void				*qp;
288 	struct ibv_pd			*pd;
289 	uint32_t			max_queue_depth;
290 	uint32_t			in_capsule_data_size;
291 	bool				shared;
292 };
293 
294 struct spdk_nvmf_send_wr_list {
295 	struct ibv_send_wr	*first;
296 	struct ibv_send_wr	*last;
297 };
298 
299 struct spdk_nvmf_recv_wr_list {
300 	struct ibv_recv_wr	*first;
301 	struct ibv_recv_wr	*last;
302 };
303 
304 struct spdk_nvmf_rdma_resources {
305 	/* Array of size "max_queue_depth" containing RDMA requests. */
306 	struct spdk_nvmf_rdma_request		*reqs;
307 
308 	/* Array of size "max_queue_depth" containing RDMA recvs. */
309 	struct spdk_nvmf_rdma_recv		*recvs;
310 
311 	/* Array of size "max_queue_depth" containing 64 byte capsules
312 	 * used for receive.
313 	 */
314 	union nvmf_h2c_msg			*cmds;
315 	struct ibv_mr				*cmds_mr;
316 
317 	/* Array of size "max_queue_depth" containing 16 byte completions
318 	 * to be sent back to the user.
319 	 */
320 	union nvmf_c2h_msg			*cpls;
321 	struct ibv_mr				*cpls_mr;
322 
323 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
324 	 * buffers to be used for in capsule data.
325 	 */
326 	void					*bufs;
327 	struct ibv_mr				*bufs_mr;
328 
329 	/* The list of pending recvs to transfer */
330 	struct spdk_nvmf_recv_wr_list		recvs_to_post;
331 
332 	/* Receives that are waiting for a request object */
333 	STAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
334 
335 	/* Queue to track free requests */
336 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	free_queue;
337 };
338 
339 struct spdk_nvmf_rdma_qpair {
340 	struct spdk_nvmf_qpair			qpair;
341 
342 	struct spdk_nvmf_rdma_port		*port;
343 	struct spdk_nvmf_rdma_poller		*poller;
344 
345 	struct rdma_cm_id			*cm_id;
346 	struct ibv_srq				*srq;
347 	struct rdma_cm_id			*listen_id;
348 
349 	/* The maximum number of I/O outstanding on this connection at one time */
350 	uint16_t				max_queue_depth;
351 
352 	/* The maximum number of active RDMA READ and ATOMIC operations at one time */
353 	uint16_t				max_read_depth;
354 
355 	/* The maximum number of RDMA SEND operations at one time */
356 	uint32_t				max_send_depth;
357 
358 	/* The current number of outstanding WRs from this qpair's
359 	 * recv queue. Should not exceed device->attr.max_queue_depth.
360 	 */
361 	uint16_t				current_recv_depth;
362 
363 	/* The current number of active RDMA READ operations */
364 	uint16_t				current_read_depth;
365 
366 	/* The current number of posted WRs from this qpair's
367 	 * send queue. Should not exceed max_send_depth.
368 	 */
369 	uint32_t				current_send_depth;
370 
371 	/* The maximum number of SGEs per WR on the send queue */
372 	uint32_t				max_send_sge;
373 
374 	/* The maximum number of SGEs per WR on the recv queue */
375 	uint32_t				max_recv_sge;
376 
377 	/* The list of pending send requests for a transfer */
378 	struct spdk_nvmf_send_wr_list		sends_to_post;
379 
380 	struct spdk_nvmf_rdma_resources		*resources;
381 
382 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_read_queue;
383 
384 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_write_queue;
385 
386 	/* Number of requests not in the free state */
387 	uint32_t				qd;
388 
389 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	link;
390 
391 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	recv_link;
392 
393 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	send_link;
394 
395 	/* IBV queue pair attributes: they are used to manage
396 	 * qp state and recover from errors.
397 	 */
398 	enum ibv_qp_state			ibv_state;
399 
400 	uint32_t				disconnect_flags;
401 
402 	/* Poller registered in case the qpair doesn't properly
403 	 * complete the qpair destruct process and becomes defunct.
404 	 */
405 
406 	struct spdk_poller			*destruct_poller;
407 
408 	/* There are several ways a disconnect can start on a qpair
409 	 * and they are not all mutually exclusive. It is important
410 	 * that we only initialize one of these paths.
411 	 */
412 	bool					disconnect_started;
413 	/* Lets us know that we have received the last_wqe event. */
414 	bool					last_wqe_reached;
415 };
416 
417 struct spdk_nvmf_rdma_poller_stat {
418 	uint64_t				completions;
419 	uint64_t				polls;
420 	uint64_t				requests;
421 	uint64_t				request_latency;
422 	uint64_t				pending_free_request;
423 	uint64_t				pending_rdma_read;
424 	uint64_t				pending_rdma_write;
425 };
426 
427 struct spdk_nvmf_rdma_poller {
428 	struct spdk_nvmf_rdma_device		*device;
429 	struct spdk_nvmf_rdma_poll_group	*group;
430 
431 	int					num_cqe;
432 	int					required_num_wr;
433 	struct ibv_cq				*cq;
434 
435 	/* The maximum number of I/O outstanding on the shared receive queue at one time */
436 	uint16_t				max_srq_depth;
437 
438 	/* Shared receive queue */
439 	struct ibv_srq				*srq;
440 
441 	struct spdk_nvmf_rdma_resources		*resources;
442 	struct spdk_nvmf_rdma_poller_stat	stat;
443 
444 	TAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs;
445 
446 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_recv;
447 
448 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_send;
449 
450 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
451 };
452 
453 struct spdk_nvmf_rdma_poll_group_stat {
454 	uint64_t				pending_data_buffer;
455 };
456 
457 struct spdk_nvmf_rdma_poll_group {
458 	struct spdk_nvmf_transport_poll_group		group;
459 	struct spdk_nvmf_rdma_poll_group_stat		stat;
460 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)		pollers;
461 	TAILQ_ENTRY(spdk_nvmf_rdma_poll_group)		link;
462 	/*
463 	 * buffers which are split across multiple RDMA
464 	 * memory regions cannot be used by this transport.
465 	 */
466 	STAILQ_HEAD(, spdk_nvmf_transport_pg_cache_buf)	retired_bufs;
467 };
468 
469 struct spdk_nvmf_rdma_conn_sched {
470 	struct spdk_nvmf_rdma_poll_group *next_admin_pg;
471 	struct spdk_nvmf_rdma_poll_group *next_io_pg;
472 };
473 
474 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
475 struct spdk_nvmf_rdma_device {
476 	struct ibv_device_attr			attr;
477 	struct ibv_context			*context;
478 
479 	struct spdk_mem_map			*map;
480 	struct ibv_pd				*pd;
481 
482 	int					num_srq;
483 
484 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
485 };
486 
487 struct spdk_nvmf_rdma_port {
488 	struct spdk_nvme_transport_id		trid;
489 	struct rdma_cm_id			*id;
490 	struct spdk_nvmf_rdma_device		*device;
491 	uint32_t				ref;
492 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
493 };
494 
495 struct spdk_nvmf_rdma_transport {
496 	struct spdk_nvmf_transport	transport;
497 
498 	struct spdk_nvmf_rdma_conn_sched conn_sched;
499 
500 	struct rdma_event_channel	*event_channel;
501 
502 	struct spdk_mempool		*data_wr_pool;
503 
504 	pthread_mutex_t			lock;
505 
506 	/* fields used to poll RDMA/IB events */
507 	nfds_t			npoll_fds;
508 	struct pollfd		*poll_fds;
509 
510 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
511 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
512 	TAILQ_HEAD(, spdk_nvmf_rdma_poll_group)	poll_groups;
513 };
514 
515 static inline void
516 spdk_nvmf_rdma_start_disconnect(struct spdk_nvmf_rdma_qpair *rqpair);
517 
518 static inline int
519 spdk_nvmf_rdma_check_ibv_state(enum ibv_qp_state state)
520 {
521 	switch (state) {
522 	case IBV_QPS_RESET:
523 	case IBV_QPS_INIT:
524 	case IBV_QPS_RTR:
525 	case IBV_QPS_RTS:
526 	case IBV_QPS_SQD:
527 	case IBV_QPS_SQE:
528 	case IBV_QPS_ERR:
529 		return 0;
530 	default:
531 		return -1;
532 	}
533 }
534 
535 static inline enum spdk_nvme_media_error_status_code
536 spdk_nvmf_rdma_dif_error_to_compl_status(uint8_t err_type) {
537 	enum spdk_nvme_media_error_status_code result;
538 	switch (err_type)
539 	{
540 	case SPDK_DIF_REFTAG_ERROR:
541 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
542 		break;
543 	case SPDK_DIF_APPTAG_ERROR:
544 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
545 		break;
546 	case SPDK_DIF_GUARD_ERROR:
547 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
548 		break;
549 	default:
550 		SPDK_UNREACHABLE();
551 	}
552 
553 	return result;
554 }
555 
556 static enum ibv_qp_state
557 spdk_nvmf_rdma_update_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair) {
558 	enum ibv_qp_state old_state, new_state;
559 	struct ibv_qp_attr qp_attr;
560 	struct ibv_qp_init_attr init_attr;
561 	int rc;
562 
563 	old_state = rqpair->ibv_state;
564 	rc = ibv_query_qp(rqpair->cm_id->qp, &qp_attr,
565 			  g_spdk_nvmf_ibv_query_mask, &init_attr);
566 
567 	if (rc)
568 	{
569 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
570 		return IBV_QPS_ERR + 1;
571 	}
572 
573 	new_state = qp_attr.qp_state;
574 	rqpair->ibv_state = new_state;
575 	qp_attr.ah_attr.port_num = qp_attr.port_num;
576 
577 	rc = spdk_nvmf_rdma_check_ibv_state(new_state);
578 	if (rc)
579 	{
580 		SPDK_ERRLOG("QP#%d: bad state updated: %u, maybe hardware issue\n", rqpair->qpair.qid, new_state);
581 		/*
582 		 * IBV_QPS_UNKNOWN undefined if lib version smaller than libibverbs-1.1.8
583 		 * IBV_QPS_UNKNOWN is the enum element after IBV_QPS_ERR
584 		 */
585 		return IBV_QPS_ERR + 1;
586 	}
587 
588 	if (old_state != new_state)
589 	{
590 		spdk_trace_record(TRACE_RDMA_QP_STATE_CHANGE, 0, 0,
591 				  (uintptr_t)rqpair->cm_id, new_state);
592 	}
593 	return new_state;
594 }
595 
596 static const char *str_ibv_qp_state[] = {
597 	"IBV_QPS_RESET",
598 	"IBV_QPS_INIT",
599 	"IBV_QPS_RTR",
600 	"IBV_QPS_RTS",
601 	"IBV_QPS_SQD",
602 	"IBV_QPS_SQE",
603 	"IBV_QPS_ERR",
604 	"IBV_QPS_UNKNOWN"
605 };
606 
607 static int
608 spdk_nvmf_rdma_set_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair,
609 			     enum ibv_qp_state new_state)
610 {
611 	struct ibv_qp_attr qp_attr;
612 	struct ibv_qp_init_attr init_attr;
613 	int rc;
614 	enum ibv_qp_state state;
615 	static int attr_mask_rc[] = {
616 		[IBV_QPS_RESET] = IBV_QP_STATE,
617 		[IBV_QPS_INIT] = (IBV_QP_STATE |
618 				  IBV_QP_PKEY_INDEX |
619 				  IBV_QP_PORT |
620 				  IBV_QP_ACCESS_FLAGS),
621 		[IBV_QPS_RTR] = (IBV_QP_STATE |
622 				 IBV_QP_AV |
623 				 IBV_QP_PATH_MTU |
624 				 IBV_QP_DEST_QPN |
625 				 IBV_QP_RQ_PSN |
626 				 IBV_QP_MAX_DEST_RD_ATOMIC |
627 				 IBV_QP_MIN_RNR_TIMER),
628 		[IBV_QPS_RTS] = (IBV_QP_STATE |
629 				 IBV_QP_SQ_PSN |
630 				 IBV_QP_TIMEOUT |
631 				 IBV_QP_RETRY_CNT |
632 				 IBV_QP_RNR_RETRY |
633 				 IBV_QP_MAX_QP_RD_ATOMIC),
634 		[IBV_QPS_SQD] = IBV_QP_STATE,
635 		[IBV_QPS_SQE] = IBV_QP_STATE,
636 		[IBV_QPS_ERR] = IBV_QP_STATE,
637 	};
638 
639 	rc = spdk_nvmf_rdma_check_ibv_state(new_state);
640 	if (rc) {
641 		SPDK_ERRLOG("QP#%d: bad state requested: %u\n",
642 			    rqpair->qpair.qid, new_state);
643 		return rc;
644 	}
645 
646 	rc = ibv_query_qp(rqpair->cm_id->qp, &qp_attr,
647 			  g_spdk_nvmf_ibv_query_mask, &init_attr);
648 
649 	if (rc) {
650 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
651 		assert(false);
652 	}
653 
654 	qp_attr.cur_qp_state = rqpair->ibv_state;
655 	qp_attr.qp_state = new_state;
656 
657 	rc = ibv_modify_qp(rqpair->cm_id->qp, &qp_attr,
658 			   attr_mask_rc[new_state]);
659 
660 	if (rc) {
661 		SPDK_ERRLOG("QP#%d: failed to set state to: %s, %d (%s)\n",
662 			    rqpair->qpair.qid, str_ibv_qp_state[new_state], errno, strerror(errno));
663 		return rc;
664 	}
665 
666 	state = spdk_nvmf_rdma_update_ibv_state(rqpair);
667 
668 	if (state != new_state) {
669 		SPDK_ERRLOG("QP#%d: expected state: %s, actual state: %s\n",
670 			    rqpair->qpair.qid, str_ibv_qp_state[new_state],
671 			    str_ibv_qp_state[state]);
672 		return -1;
673 	}
674 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "IBV QP#%u changed to: %s\n", rqpair->qpair.qid,
675 		      str_ibv_qp_state[state]);
676 	return 0;
677 }
678 
679 static void
680 nvmf_rdma_request_free_data(struct spdk_nvmf_rdma_request *rdma_req,
681 			    struct spdk_nvmf_rdma_transport *rtransport)
682 {
683 	struct spdk_nvmf_rdma_request_data	*data_wr;
684 	struct ibv_send_wr			*next_send_wr;
685 	uint64_t				req_wrid;
686 
687 	rdma_req->num_outstanding_data_wr = 0;
688 	data_wr = &rdma_req->data;
689 	req_wrid = data_wr->wr.wr_id;
690 	while (data_wr && data_wr->wr.wr_id == req_wrid) {
691 		memset(data_wr->sgl, 0, sizeof(data_wr->wr.sg_list[0]) * data_wr->wr.num_sge);
692 		data_wr->wr.num_sge = 0;
693 		next_send_wr = data_wr->wr.next;
694 		if (data_wr != &rdma_req->data) {
695 			spdk_mempool_put(rtransport->data_wr_pool, data_wr);
696 		}
697 		data_wr = (!next_send_wr || next_send_wr == &rdma_req->rsp.wr) ? NULL :
698 			  SPDK_CONTAINEROF(next_send_wr, struct spdk_nvmf_rdma_request_data, wr);
699 	}
700 }
701 
702 static void
703 nvmf_rdma_dump_request(struct spdk_nvmf_rdma_request *req)
704 {
705 	SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", req->req.data_from_pool);
706 	if (req->req.cmd) {
707 		SPDK_ERRLOG("\t\tRequest opcode: %d\n", req->req.cmd->nvmf_cmd.opcode);
708 	}
709 	if (req->recv) {
710 		SPDK_ERRLOG("\t\tRequest recv wr_id%lu\n", req->recv->wr.wr_id);
711 	}
712 }
713 
714 static void
715 nvmf_rdma_dump_qpair_contents(struct spdk_nvmf_rdma_qpair *rqpair)
716 {
717 	int i;
718 
719 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", rqpair->qpair.qid);
720 	for (i = 0; i < rqpair->max_queue_depth; i++) {
721 		if (rqpair->resources->reqs[i].state != RDMA_REQUEST_STATE_FREE) {
722 			nvmf_rdma_dump_request(&rqpair->resources->reqs[i]);
723 		}
724 	}
725 }
726 
727 static void
728 nvmf_rdma_resources_destroy(struct spdk_nvmf_rdma_resources *resources)
729 {
730 	if (resources->cmds_mr) {
731 		ibv_dereg_mr(resources->cmds_mr);
732 	}
733 
734 	if (resources->cpls_mr) {
735 		ibv_dereg_mr(resources->cpls_mr);
736 	}
737 
738 	if (resources->bufs_mr) {
739 		ibv_dereg_mr(resources->bufs_mr);
740 	}
741 
742 	spdk_free(resources->cmds);
743 	spdk_free(resources->cpls);
744 	spdk_free(resources->bufs);
745 	free(resources->reqs);
746 	free(resources->recvs);
747 	free(resources);
748 }
749 
750 
751 static struct spdk_nvmf_rdma_resources *
752 nvmf_rdma_resources_create(struct spdk_nvmf_rdma_resource_opts *opts)
753 {
754 	struct spdk_nvmf_rdma_resources	*resources;
755 	struct spdk_nvmf_rdma_request	*rdma_req;
756 	struct spdk_nvmf_rdma_recv	*rdma_recv;
757 	struct ibv_qp			*qp;
758 	struct ibv_srq			*srq;
759 	uint32_t			i;
760 	int				rc;
761 
762 	resources = calloc(1, sizeof(struct spdk_nvmf_rdma_resources));
763 	if (!resources) {
764 		SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
765 		return NULL;
766 	}
767 
768 	resources->reqs = calloc(opts->max_queue_depth, sizeof(*resources->reqs));
769 	resources->recvs = calloc(opts->max_queue_depth, sizeof(*resources->recvs));
770 	resources->cmds = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cmds),
771 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
772 	resources->cpls = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cpls),
773 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
774 
775 	if (opts->in_capsule_data_size > 0) {
776 		resources->bufs = spdk_zmalloc(opts->max_queue_depth * opts->in_capsule_data_size,
777 					       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY,
778 					       SPDK_MALLOC_DMA);
779 	}
780 
781 	if (!resources->reqs || !resources->recvs || !resources->cmds ||
782 	    !resources->cpls || (opts->in_capsule_data_size && !resources->bufs)) {
783 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
784 		goto cleanup;
785 	}
786 
787 	resources->cmds_mr = ibv_reg_mr(opts->pd, resources->cmds,
788 					opts->max_queue_depth * sizeof(*resources->cmds),
789 					IBV_ACCESS_LOCAL_WRITE);
790 	resources->cpls_mr = ibv_reg_mr(opts->pd, resources->cpls,
791 					opts->max_queue_depth * sizeof(*resources->cpls),
792 					0);
793 
794 	if (opts->in_capsule_data_size) {
795 		resources->bufs_mr = ibv_reg_mr(opts->pd, resources->bufs,
796 						opts->max_queue_depth *
797 						opts->in_capsule_data_size,
798 						IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
799 	}
800 
801 	if (!resources->cmds_mr || !resources->cpls_mr ||
802 	    (opts->in_capsule_data_size &&
803 	     !resources->bufs_mr)) {
804 		goto cleanup;
805 	}
806 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Command Array: %p Length: %lx LKey: %x\n",
807 		      resources->cmds, opts->max_queue_depth * sizeof(*resources->cmds),
808 		      resources->cmds_mr->lkey);
809 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Completion Array: %p Length: %lx LKey: %x\n",
810 		      resources->cpls, opts->max_queue_depth * sizeof(*resources->cpls),
811 		      resources->cpls_mr->lkey);
812 	if (resources->bufs && resources->bufs_mr) {
813 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "In Capsule Data Array: %p Length: %x LKey: %x\n",
814 			      resources->bufs, opts->max_queue_depth *
815 			      opts->in_capsule_data_size, resources->bufs_mr->lkey);
816 	}
817 
818 	/* Initialize queues */
819 	STAILQ_INIT(&resources->incoming_queue);
820 	STAILQ_INIT(&resources->free_queue);
821 
822 	for (i = 0; i < opts->max_queue_depth; i++) {
823 		struct ibv_recv_wr *bad_wr = NULL;
824 
825 		rdma_recv = &resources->recvs[i];
826 		rdma_recv->qpair = opts->qpair;
827 
828 		/* Set up memory to receive commands */
829 		if (resources->bufs) {
830 			rdma_recv->buf = (void *)((uintptr_t)resources->bufs + (i *
831 						  opts->in_capsule_data_size));
832 		}
833 
834 		rdma_recv->rdma_wr.type = RDMA_WR_TYPE_RECV;
835 
836 		rdma_recv->sgl[0].addr = (uintptr_t)&resources->cmds[i];
837 		rdma_recv->sgl[0].length = sizeof(resources->cmds[i]);
838 		rdma_recv->sgl[0].lkey = resources->cmds_mr->lkey;
839 		rdma_recv->wr.num_sge = 1;
840 
841 		if (rdma_recv->buf && resources->bufs_mr) {
842 			rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
843 			rdma_recv->sgl[1].length = opts->in_capsule_data_size;
844 			rdma_recv->sgl[1].lkey = resources->bufs_mr->lkey;
845 			rdma_recv->wr.num_sge++;
846 		}
847 
848 		rdma_recv->wr.wr_id = (uintptr_t)&rdma_recv->rdma_wr;
849 		rdma_recv->wr.sg_list = rdma_recv->sgl;
850 		if (opts->shared) {
851 			srq = (struct ibv_srq *)opts->qp;
852 			rc = ibv_post_srq_recv(srq, &rdma_recv->wr, &bad_wr);
853 		} else {
854 			qp = (struct ibv_qp *)opts->qp;
855 			rc = ibv_post_recv(qp, &rdma_recv->wr, &bad_wr);
856 		}
857 		if (rc) {
858 			goto cleanup;
859 		}
860 	}
861 
862 	for (i = 0; i < opts->max_queue_depth; i++) {
863 		rdma_req = &resources->reqs[i];
864 
865 		if (opts->qpair != NULL) {
866 			rdma_req->req.qpair = &opts->qpair->qpair;
867 		} else {
868 			rdma_req->req.qpair = NULL;
869 		}
870 		rdma_req->req.cmd = NULL;
871 
872 		/* Set up memory to send responses */
873 		rdma_req->req.rsp = &resources->cpls[i];
874 
875 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&resources->cpls[i];
876 		rdma_req->rsp.sgl[0].length = sizeof(resources->cpls[i]);
877 		rdma_req->rsp.sgl[0].lkey = resources->cpls_mr->lkey;
878 
879 		rdma_req->rsp.rdma_wr.type = RDMA_WR_TYPE_SEND;
880 		rdma_req->rsp.wr.wr_id = (uintptr_t)&rdma_req->rsp.rdma_wr;
881 		rdma_req->rsp.wr.next = NULL;
882 		rdma_req->rsp.wr.opcode = IBV_WR_SEND;
883 		rdma_req->rsp.wr.send_flags = IBV_SEND_SIGNALED;
884 		rdma_req->rsp.wr.sg_list = rdma_req->rsp.sgl;
885 		rdma_req->rsp.wr.num_sge = SPDK_COUNTOF(rdma_req->rsp.sgl);
886 
887 		/* Set up memory for data buffers */
888 		rdma_req->data.rdma_wr.type = RDMA_WR_TYPE_DATA;
889 		rdma_req->data.wr.wr_id = (uintptr_t)&rdma_req->data.rdma_wr;
890 		rdma_req->data.wr.next = NULL;
891 		rdma_req->data.wr.send_flags = IBV_SEND_SIGNALED;
892 		rdma_req->data.wr.sg_list = rdma_req->data.sgl;
893 		rdma_req->data.wr.num_sge = SPDK_COUNTOF(rdma_req->data.sgl);
894 
895 		/* Initialize request state to FREE */
896 		rdma_req->state = RDMA_REQUEST_STATE_FREE;
897 		STAILQ_INSERT_TAIL(&resources->free_queue, rdma_req, state_link);
898 	}
899 
900 	return resources;
901 
902 cleanup:
903 	nvmf_rdma_resources_destroy(resources);
904 	return NULL;
905 }
906 
907 static void
908 spdk_nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
909 {
910 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
911 	struct ibv_recv_wr		*bad_recv_wr = NULL;
912 	int				rc;
913 
914 	spdk_trace_record(TRACE_RDMA_QP_DESTROY, 0, 0, (uintptr_t)rqpair->cm_id, 0);
915 
916 	spdk_poller_unregister(&rqpair->destruct_poller);
917 
918 	if (rqpair->qd != 0) {
919 		if (rqpair->srq == NULL) {
920 			nvmf_rdma_dump_qpair_contents(rqpair);
921 		}
922 		SPDK_WARNLOG("Destroying qpair when queue depth is %d\n", rqpair->qd);
923 	}
924 
925 	if (rqpair->poller) {
926 		TAILQ_REMOVE(&rqpair->poller->qpairs, rqpair, link);
927 
928 		if (rqpair->srq != NULL && rqpair->resources != NULL) {
929 			/* Drop all received but unprocessed commands for this queue and return them to SRQ */
930 			STAILQ_FOREACH_SAFE(rdma_recv, &rqpair->resources->incoming_queue, link, recv_tmp) {
931 				if (rqpair == rdma_recv->qpair) {
932 					STAILQ_REMOVE_HEAD(&rqpair->resources->incoming_queue, link);
933 					rc = ibv_post_srq_recv(rqpair->srq, &rdma_recv->wr, &bad_recv_wr);
934 					if (rc) {
935 						SPDK_ERRLOG("Unable to re-post rx descriptor\n");
936 					}
937 				}
938 			}
939 		}
940 	}
941 
942 	if (rqpair->cm_id) {
943 		if (rqpair->cm_id->qp != NULL) {
944 			rdma_destroy_qp(rqpair->cm_id);
945 		}
946 		rdma_destroy_id(rqpair->cm_id);
947 
948 		if (rqpair->poller != NULL && rqpair->srq == NULL) {
949 			rqpair->poller->required_num_wr -= MAX_WR_PER_QP(rqpair->max_queue_depth);
950 		}
951 	}
952 
953 	if (rqpair->srq == NULL && rqpair->resources != NULL) {
954 		nvmf_rdma_resources_destroy(rqpair->resources);
955 	}
956 
957 	free(rqpair);
958 }
959 
960 static int
961 nvmf_rdma_resize_cq(struct spdk_nvmf_rdma_qpair *rqpair, struct spdk_nvmf_rdma_device *device)
962 {
963 	struct spdk_nvmf_rdma_poller	*rpoller;
964 	int				rc, num_cqe, required_num_wr;
965 
966 	/* Enlarge CQ size dynamically */
967 	rpoller = rqpair->poller;
968 	required_num_wr = rpoller->required_num_wr + MAX_WR_PER_QP(rqpair->max_queue_depth);
969 	num_cqe = rpoller->num_cqe;
970 	if (num_cqe < required_num_wr) {
971 		num_cqe = spdk_max(num_cqe * 2, required_num_wr);
972 		num_cqe = spdk_min(num_cqe, device->attr.max_cqe);
973 	}
974 
975 	if (rpoller->num_cqe != num_cqe) {
976 		if (required_num_wr > device->attr.max_cqe) {
977 			SPDK_ERRLOG("RDMA CQE requirement (%d) exceeds device max_cqe limitation (%d)\n",
978 				    required_num_wr, device->attr.max_cqe);
979 			return -1;
980 		}
981 
982 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Resize RDMA CQ from %d to %d\n", rpoller->num_cqe, num_cqe);
983 		rc = ibv_resize_cq(rpoller->cq, num_cqe);
984 		if (rc) {
985 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
986 			return -1;
987 		}
988 
989 		rpoller->num_cqe = num_cqe;
990 	}
991 
992 	rpoller->required_num_wr = required_num_wr;
993 	return 0;
994 }
995 
996 static int
997 spdk_nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
998 {
999 	struct spdk_nvmf_rdma_qpair		*rqpair;
1000 	int					rc;
1001 	struct spdk_nvmf_rdma_transport		*rtransport;
1002 	struct spdk_nvmf_transport		*transport;
1003 	struct spdk_nvmf_rdma_resource_opts	opts;
1004 	struct spdk_nvmf_rdma_device		*device;
1005 	struct ibv_qp_init_attr			ibv_init_attr;
1006 
1007 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1008 	device = rqpair->port->device;
1009 
1010 	memset(&ibv_init_attr, 0, sizeof(struct ibv_qp_init_attr));
1011 	ibv_init_attr.qp_context	= rqpair;
1012 	ibv_init_attr.qp_type		= IBV_QPT_RC;
1013 	ibv_init_attr.send_cq		= rqpair->poller->cq;
1014 	ibv_init_attr.recv_cq		= rqpair->poller->cq;
1015 
1016 	if (rqpair->srq) {
1017 		ibv_init_attr.srq		= rqpair->srq;
1018 	} else {
1019 		ibv_init_attr.cap.max_recv_wr	= rqpair->max_queue_depth +
1020 						  1; /* RECV operations + dummy drain WR */
1021 	}
1022 
1023 	ibv_init_attr.cap.max_send_wr	= rqpair->max_queue_depth *
1024 					  2 + 1; /* SEND, READ, and WRITE operations + dummy drain WR */
1025 	ibv_init_attr.cap.max_send_sge	= spdk_min(device->attr.max_sge, NVMF_DEFAULT_TX_SGE);
1026 	ibv_init_attr.cap.max_recv_sge	= spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
1027 
1028 	if (rqpair->srq == NULL && nvmf_rdma_resize_cq(rqpair, device) < 0) {
1029 		SPDK_ERRLOG("Failed to resize the completion queue. Cannot initialize qpair.\n");
1030 		goto error;
1031 	}
1032 
1033 	rc = rdma_create_qp(rqpair->cm_id, rqpair->port->device->pd, &ibv_init_attr);
1034 	if (rc) {
1035 		SPDK_ERRLOG("rdma_create_qp failed: errno %d: %s\n", errno, spdk_strerror(errno));
1036 		goto error;
1037 	}
1038 
1039 	rqpair->max_send_depth = spdk_min((uint32_t)(rqpair->max_queue_depth * 2 + 1),
1040 					  ibv_init_attr.cap.max_send_wr);
1041 	rqpair->max_send_sge = spdk_min(NVMF_DEFAULT_TX_SGE, ibv_init_attr.cap.max_send_sge);
1042 	rqpair->max_recv_sge = spdk_min(NVMF_DEFAULT_RX_SGE, ibv_init_attr.cap.max_recv_sge);
1043 	spdk_trace_record(TRACE_RDMA_QP_CREATE, 0, 0, (uintptr_t)rqpair->cm_id, 0);
1044 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "New RDMA Connection: %p\n", qpair);
1045 
1046 	rqpair->sends_to_post.first = NULL;
1047 	rqpair->sends_to_post.last = NULL;
1048 
1049 	if (rqpair->poller->srq == NULL) {
1050 		rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
1051 		transport = &rtransport->transport;
1052 
1053 		opts.qp = rqpair->cm_id->qp;
1054 		opts.pd = rqpair->cm_id->pd;
1055 		opts.qpair = rqpair;
1056 		opts.shared = false;
1057 		opts.max_queue_depth = rqpair->max_queue_depth;
1058 		opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
1059 
1060 		rqpair->resources = nvmf_rdma_resources_create(&opts);
1061 
1062 		if (!rqpair->resources) {
1063 			SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
1064 			rdma_destroy_qp(rqpair->cm_id);
1065 			goto error;
1066 		}
1067 	} else {
1068 		rqpair->resources = rqpair->poller->resources;
1069 	}
1070 
1071 	rqpair->current_recv_depth = 0;
1072 	STAILQ_INIT(&rqpair->pending_rdma_read_queue);
1073 	STAILQ_INIT(&rqpair->pending_rdma_write_queue);
1074 
1075 	return 0;
1076 
1077 error:
1078 	rdma_destroy_id(rqpair->cm_id);
1079 	rqpair->cm_id = NULL;
1080 	return -1;
1081 }
1082 
1083 /* Append the given recv wr structure to the resource structs outstanding recvs list. */
1084 /* This function accepts either a single wr or the first wr in a linked list. */
1085 static void
1086 nvmf_rdma_qpair_queue_recv_wrs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *first)
1087 {
1088 	struct ibv_recv_wr *last;
1089 
1090 	last = first;
1091 	while (last->next != NULL) {
1092 		last = last->next;
1093 	}
1094 
1095 	if (rqpair->resources->recvs_to_post.first == NULL) {
1096 		rqpair->resources->recvs_to_post.first = first;
1097 		rqpair->resources->recvs_to_post.last = last;
1098 		if (rqpair->srq == NULL) {
1099 			STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_recv, rqpair, recv_link);
1100 		}
1101 	} else {
1102 		rqpair->resources->recvs_to_post.last->next = first;
1103 		rqpair->resources->recvs_to_post.last = last;
1104 	}
1105 }
1106 
1107 /* Append the given send wr structure to the qpair's outstanding sends list. */
1108 /* This function accepts either a single wr or the first wr in a linked list. */
1109 static void
1110 nvmf_rdma_qpair_queue_send_wrs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_send_wr *first)
1111 {
1112 	struct ibv_send_wr *last;
1113 
1114 	last = first;
1115 	while (last->next != NULL) {
1116 		last = last->next;
1117 	}
1118 
1119 	if (rqpair->sends_to_post.first == NULL) {
1120 		rqpair->sends_to_post.first = first;
1121 		rqpair->sends_to_post.last = last;
1122 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1123 	} else {
1124 		rqpair->sends_to_post.last->next = first;
1125 		rqpair->sends_to_post.last = last;
1126 	}
1127 }
1128 
1129 static int
1130 request_transfer_in(struct spdk_nvmf_request *req)
1131 {
1132 	struct spdk_nvmf_rdma_request	*rdma_req;
1133 	struct spdk_nvmf_qpair		*qpair;
1134 	struct spdk_nvmf_rdma_qpair	*rqpair;
1135 
1136 	qpair = req->qpair;
1137 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1138 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1139 
1140 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
1141 	assert(rdma_req != NULL);
1142 
1143 	nvmf_rdma_qpair_queue_send_wrs(rqpair, &rdma_req->data.wr);
1144 	rqpair->current_read_depth += rdma_req->num_outstanding_data_wr;
1145 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr;
1146 	return 0;
1147 }
1148 
1149 static int
1150 request_transfer_out(struct spdk_nvmf_request *req, int *data_posted)
1151 {
1152 	int				num_outstanding_data_wr = 0;
1153 	struct spdk_nvmf_rdma_request	*rdma_req;
1154 	struct spdk_nvmf_qpair		*qpair;
1155 	struct spdk_nvmf_rdma_qpair	*rqpair;
1156 	struct spdk_nvme_cpl		*rsp;
1157 	struct ibv_send_wr		*first = NULL;
1158 
1159 	*data_posted = 0;
1160 	qpair = req->qpair;
1161 	rsp = &req->rsp->nvme_cpl;
1162 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1163 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1164 
1165 	/* Advance our sq_head pointer */
1166 	if (qpair->sq_head == qpair->sq_head_max) {
1167 		qpair->sq_head = 0;
1168 	} else {
1169 		qpair->sq_head++;
1170 	}
1171 	rsp->sqhd = qpair->sq_head;
1172 
1173 	/* queue the capsule for the recv buffer */
1174 	assert(rdma_req->recv != NULL);
1175 
1176 	nvmf_rdma_qpair_queue_recv_wrs(rqpair, &rdma_req->recv->wr);
1177 
1178 	rdma_req->recv = NULL;
1179 	assert(rqpair->current_recv_depth > 0);
1180 	rqpair->current_recv_depth--;
1181 
1182 	/* Build the response which consists of optional
1183 	 * RDMA WRITEs to transfer data, plus an RDMA SEND
1184 	 * containing the response.
1185 	 */
1186 	first = &rdma_req->rsp.wr;
1187 
1188 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
1189 	    req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1190 		first = &rdma_req->data.wr;
1191 		*data_posted = 1;
1192 		num_outstanding_data_wr = rdma_req->num_outstanding_data_wr;
1193 	}
1194 	nvmf_rdma_qpair_queue_send_wrs(rqpair, first);
1195 	/* +1 for the rsp wr */
1196 	rqpair->current_send_depth += num_outstanding_data_wr + 1;
1197 
1198 	return 0;
1199 }
1200 
1201 static int
1202 spdk_nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
1203 {
1204 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
1205 	struct rdma_conn_param				ctrlr_event_data = {};
1206 	int						rc;
1207 
1208 	accept_data.recfmt = 0;
1209 	accept_data.crqsize = rqpair->max_queue_depth;
1210 
1211 	ctrlr_event_data.private_data = &accept_data;
1212 	ctrlr_event_data.private_data_len = sizeof(accept_data);
1213 	if (id->ps == RDMA_PS_TCP) {
1214 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
1215 		ctrlr_event_data.initiator_depth = rqpair->max_read_depth;
1216 	}
1217 
1218 	/* Configure infinite retries for the initiator side qpair.
1219 	 * When using a shared receive queue on the target side,
1220 	 * we need to pass this value to the initiator to prevent the
1221 	 * initiator side NIC from completing SEND requests back to the
1222 	 * initiator with status rnr_retry_count_exceeded. */
1223 	if (rqpair->srq != NULL) {
1224 		ctrlr_event_data.rnr_retry_count = 0x7;
1225 	}
1226 
1227 	rc = rdma_accept(id, &ctrlr_event_data);
1228 	if (rc) {
1229 		SPDK_ERRLOG("Error %d on rdma_accept\n", errno);
1230 	} else {
1231 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Sent back the accept\n");
1232 	}
1233 
1234 	return rc;
1235 }
1236 
1237 static void
1238 spdk_nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
1239 {
1240 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
1241 
1242 	rej_data.recfmt = 0;
1243 	rej_data.sts = error;
1244 
1245 	rdma_reject(id, &rej_data, sizeof(rej_data));
1246 }
1247 
1248 static int
1249 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event,
1250 		  new_qpair_fn cb_fn)
1251 {
1252 	struct spdk_nvmf_rdma_transport *rtransport;
1253 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
1254 	struct spdk_nvmf_rdma_port	*port;
1255 	struct rdma_conn_param		*rdma_param = NULL;
1256 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
1257 	uint16_t			max_queue_depth;
1258 	uint16_t			max_read_depth;
1259 
1260 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1261 
1262 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
1263 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
1264 
1265 	rdma_param = &event->param.conn;
1266 	if (rdma_param->private_data == NULL ||
1267 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1268 		SPDK_ERRLOG("connect request: no private data provided\n");
1269 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
1270 		return -1;
1271 	}
1272 
1273 	private_data = rdma_param->private_data;
1274 	if (private_data->recfmt != 0) {
1275 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
1276 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
1277 		return -1;
1278 	}
1279 
1280 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Connect Recv on fabric intf name %s, dev_name %s\n",
1281 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
1282 
1283 	port = event->listen_id->context;
1284 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
1285 		      event->listen_id, event->listen_id->verbs, port);
1286 
1287 	/* Figure out the supported queue depth. This is a multi-step process
1288 	 * that takes into account hardware maximums, host provided values,
1289 	 * and our target's internal memory limits */
1290 
1291 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Calculating Queue Depth\n");
1292 
1293 	/* Start with the maximum queue depth allowed by the target */
1294 	max_queue_depth = rtransport->transport.opts.max_queue_depth;
1295 	max_read_depth = rtransport->transport.opts.max_queue_depth;
1296 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Target Max Queue Depth: %d\n",
1297 		      rtransport->transport.opts.max_queue_depth);
1298 
1299 	/* Next check the local NIC's hardware limitations */
1300 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
1301 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
1302 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
1303 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
1304 	max_read_depth = spdk_min(max_read_depth, port->device->attr.max_qp_init_rd_atom);
1305 
1306 	/* Next check the remote NIC's hardware limitations */
1307 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
1308 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
1309 		      rdma_param->initiator_depth, rdma_param->responder_resources);
1310 	if (rdma_param->initiator_depth > 0) {
1311 		max_read_depth = spdk_min(max_read_depth, rdma_param->initiator_depth);
1312 	}
1313 
1314 	/* Finally check for the host software requested values, which are
1315 	 * optional. */
1316 	if (rdma_param->private_data != NULL &&
1317 	    rdma_param->private_data_len >= sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1318 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1319 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Send Queue Size: %d\n", private_data->hsqsize);
1320 		max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
1321 		max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
1322 	}
1323 
1324 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
1325 		      max_queue_depth, max_read_depth);
1326 
1327 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
1328 	if (rqpair == NULL) {
1329 		SPDK_ERRLOG("Could not allocate new connection.\n");
1330 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1331 		return -1;
1332 	}
1333 
1334 	rqpair->port = port;
1335 	rqpair->max_queue_depth = max_queue_depth;
1336 	rqpair->max_read_depth = max_read_depth;
1337 	rqpair->cm_id = event->id;
1338 	rqpair->listen_id = event->listen_id;
1339 	rqpair->qpair.transport = transport;
1340 	/* use qid from the private data to determine the qpair type
1341 	   qid will be set to the appropriate value when the controller is created */
1342 	rqpair->qpair.qid = private_data->qid;
1343 
1344 	event->id->context = &rqpair->qpair;
1345 
1346 	cb_fn(&rqpair->qpair);
1347 
1348 	return 0;
1349 }
1350 
1351 static int
1352 spdk_nvmf_rdma_mem_notify(void *cb_ctx, struct spdk_mem_map *map,
1353 			  enum spdk_mem_map_notify_action action,
1354 			  void *vaddr, size_t size)
1355 {
1356 	struct ibv_pd *pd = cb_ctx;
1357 	struct ibv_mr *mr;
1358 	int rc;
1359 
1360 	switch (action) {
1361 	case SPDK_MEM_MAP_NOTIFY_REGISTER:
1362 		if (!g_nvmf_hooks.get_rkey) {
1363 			mr = ibv_reg_mr(pd, vaddr, size,
1364 					IBV_ACCESS_LOCAL_WRITE |
1365 					IBV_ACCESS_REMOTE_READ |
1366 					IBV_ACCESS_REMOTE_WRITE);
1367 			if (mr == NULL) {
1368 				SPDK_ERRLOG("ibv_reg_mr() failed\n");
1369 				return -1;
1370 			} else {
1371 				rc = spdk_mem_map_set_translation(map, (uint64_t)vaddr, size, (uint64_t)mr);
1372 			}
1373 		} else {
1374 			rc = spdk_mem_map_set_translation(map, (uint64_t)vaddr, size,
1375 							  g_nvmf_hooks.get_rkey(pd, vaddr, size));
1376 		}
1377 		break;
1378 	case SPDK_MEM_MAP_NOTIFY_UNREGISTER:
1379 		if (!g_nvmf_hooks.get_rkey) {
1380 			mr = (struct ibv_mr *)spdk_mem_map_translate(map, (uint64_t)vaddr, NULL);
1381 			if (mr) {
1382 				ibv_dereg_mr(mr);
1383 			}
1384 		}
1385 		rc = spdk_mem_map_clear_translation(map, (uint64_t)vaddr, size);
1386 		break;
1387 	default:
1388 		SPDK_UNREACHABLE();
1389 	}
1390 
1391 	return rc;
1392 }
1393 
1394 static int
1395 spdk_nvmf_rdma_check_contiguous_entries(uint64_t addr_1, uint64_t addr_2)
1396 {
1397 	/* Two contiguous mappings will point to the same address which is the start of the RDMA MR. */
1398 	return addr_1 == addr_2;
1399 }
1400 
1401 typedef enum spdk_nvme_data_transfer spdk_nvme_data_transfer_t;
1402 
1403 static spdk_nvme_data_transfer_t
1404 spdk_nvmf_rdma_request_get_xfer(struct spdk_nvmf_rdma_request *rdma_req)
1405 {
1406 	enum spdk_nvme_data_transfer xfer;
1407 	struct spdk_nvme_cmd *cmd = &rdma_req->req.cmd->nvme_cmd;
1408 	struct spdk_nvme_sgl_descriptor *sgl = &cmd->dptr.sgl1;
1409 
1410 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1411 	rdma_req->rsp.wr.opcode = IBV_WR_SEND;
1412 	rdma_req->rsp.wr.imm_data = 0;
1413 #endif
1414 
1415 	/* Figure out data transfer direction */
1416 	if (cmd->opc == SPDK_NVME_OPC_FABRIC) {
1417 		xfer = spdk_nvme_opc_get_data_transfer(rdma_req->req.cmd->nvmf_cmd.fctype);
1418 	} else {
1419 		xfer = spdk_nvme_opc_get_data_transfer(cmd->opc);
1420 
1421 		/* Some admin commands are special cases */
1422 		if ((rdma_req->req.qpair->qid == 0) &&
1423 		    ((cmd->opc == SPDK_NVME_OPC_GET_FEATURES) ||
1424 		     (cmd->opc == SPDK_NVME_OPC_SET_FEATURES))) {
1425 			switch (cmd->cdw10 & 0xff) {
1426 			case SPDK_NVME_FEAT_LBA_RANGE_TYPE:
1427 			case SPDK_NVME_FEAT_AUTONOMOUS_POWER_STATE_TRANSITION:
1428 			case SPDK_NVME_FEAT_HOST_IDENTIFIER:
1429 				break;
1430 			default:
1431 				xfer = SPDK_NVME_DATA_NONE;
1432 			}
1433 		}
1434 	}
1435 
1436 	if (xfer == SPDK_NVME_DATA_NONE) {
1437 		return xfer;
1438 	}
1439 
1440 	/* Even for commands that may transfer data, they could have specified 0 length.
1441 	 * We want those to show up with xfer SPDK_NVME_DATA_NONE.
1442 	 */
1443 	switch (sgl->generic.type) {
1444 	case SPDK_NVME_SGL_TYPE_DATA_BLOCK:
1445 	case SPDK_NVME_SGL_TYPE_BIT_BUCKET:
1446 	case SPDK_NVME_SGL_TYPE_SEGMENT:
1447 	case SPDK_NVME_SGL_TYPE_LAST_SEGMENT:
1448 	case SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK:
1449 		if (sgl->unkeyed.length == 0) {
1450 			xfer = SPDK_NVME_DATA_NONE;
1451 		}
1452 		break;
1453 	case SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK:
1454 		if (sgl->keyed.length == 0) {
1455 			xfer = SPDK_NVME_DATA_NONE;
1456 		}
1457 		break;
1458 	}
1459 
1460 	return xfer;
1461 }
1462 
1463 static int
1464 nvmf_request_alloc_wrs(struct spdk_nvmf_rdma_transport *rtransport,
1465 		       struct spdk_nvmf_rdma_request *rdma_req,
1466 		       uint32_t num_sgl_descriptors)
1467 {
1468 	struct spdk_nvmf_rdma_request_data	*work_requests[SPDK_NVMF_MAX_SGL_ENTRIES];
1469 	struct spdk_nvmf_rdma_request_data	*current_data_wr;
1470 	uint32_t				i;
1471 
1472 	if (spdk_mempool_get_bulk(rtransport->data_wr_pool, (void **)work_requests, num_sgl_descriptors)) {
1473 		return -ENOMEM;
1474 	}
1475 
1476 	current_data_wr = &rdma_req->data;
1477 
1478 	for (i = 0; i < num_sgl_descriptors; i++) {
1479 		if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1480 			current_data_wr->wr.opcode = IBV_WR_RDMA_WRITE;
1481 			current_data_wr->wr.send_flags = 0;
1482 		} else if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1483 			current_data_wr->wr.opcode = IBV_WR_RDMA_READ;
1484 			current_data_wr->wr.send_flags = IBV_SEND_SIGNALED;
1485 		} else {
1486 			assert(false);
1487 		}
1488 		work_requests[i]->wr.sg_list = work_requests[i]->sgl;
1489 		work_requests[i]->wr.wr_id = rdma_req->data.wr.wr_id;
1490 		current_data_wr->wr.next = &work_requests[i]->wr;
1491 		current_data_wr = work_requests[i];
1492 	}
1493 
1494 	if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1495 		current_data_wr->wr.opcode = IBV_WR_RDMA_WRITE;
1496 		current_data_wr->wr.next = &rdma_req->rsp.wr;
1497 		current_data_wr->wr.send_flags = 0;
1498 	} else if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1499 		current_data_wr->wr.opcode = IBV_WR_RDMA_READ;
1500 		current_data_wr->wr.next = NULL;
1501 		current_data_wr->wr.send_flags = IBV_SEND_SIGNALED;
1502 	}
1503 	return 0;
1504 }
1505 
1506 /* This function is used in the rare case that we have a buffer split over multiple memory regions. */
1507 static int
1508 nvmf_rdma_replace_buffer(struct spdk_nvmf_rdma_poll_group *rgroup, void **buf)
1509 {
1510 	struct spdk_nvmf_transport_poll_group	*group = &rgroup->group;
1511 	struct spdk_nvmf_transport		*transport = group->transport;
1512 	struct spdk_nvmf_transport_pg_cache_buf	*old_buf;
1513 	void					*new_buf;
1514 
1515 	if (!(STAILQ_EMPTY(&group->buf_cache))) {
1516 		group->buf_cache_count--;
1517 		new_buf = STAILQ_FIRST(&group->buf_cache);
1518 		STAILQ_REMOVE_HEAD(&group->buf_cache, link);
1519 		assert(*buf != NULL);
1520 	} else {
1521 		new_buf = spdk_mempool_get(transport->data_buf_pool);
1522 	}
1523 
1524 	if (*buf == NULL) {
1525 		return -ENOMEM;
1526 	}
1527 
1528 	old_buf = *buf;
1529 	STAILQ_INSERT_HEAD(&rgroup->retired_bufs, old_buf, link);
1530 	*buf = new_buf;
1531 	return 0;
1532 }
1533 
1534 /*
1535  * Fills iov and SGL, iov[i] points to buffer[i], SGE[i] is limited in length to data block size
1536  * and points to part of buffer
1537  */
1538 static int
1539 nvmf_rdma_fill_buffers_with_md_interleave(struct spdk_nvmf_rdma_transport *rtransport,
1540 		struct spdk_nvmf_rdma_poll_group *rgroup,
1541 		struct spdk_nvmf_rdma_device *device,
1542 		struct spdk_nvmf_request *req,
1543 		struct ibv_send_wr *wr,
1544 		uint32_t length,
1545 		uint32_t data_block_size,
1546 		uint32_t md_size)
1547 {
1548 	uint32_t remaining_length = length;
1549 	uint32_t remaining_io_buffer_length;
1550 	uint32_t remaining_data_block = data_block_size;
1551 	uint32_t offset = 0;
1552 	uint32_t sge_len;
1553 	uint64_t translation_len;
1554 	struct iovec *iovec;
1555 	struct ibv_sge *sg_list;
1556 	uint32_t lkey = 0;
1557 
1558 	wr->num_sge = 0;
1559 
1560 	while (remaining_length && wr->num_sge < SPDK_NVMF_MAX_SGL_ENTRIES) {
1561 		iovec = &req->iov[req->iovcnt];
1562 		iovec->iov_base = (void *)((uintptr_t)(req->buffers[req->iovcnt] + NVMF_DATA_BUFFER_MASK)
1563 					   & ~NVMF_DATA_BUFFER_MASK);
1564 		iovec->iov_len = spdk_min(remaining_length, rtransport->transport.opts.io_unit_size);
1565 		remaining_io_buffer_length = iovec->iov_len - offset;
1566 		translation_len = iovec->iov_len;
1567 
1568 		if (!g_nvmf_hooks.get_rkey) {
1569 			lkey = ((struct ibv_mr *)spdk_mem_map_translate(device->map, (uint64_t)iovec->iov_base,
1570 					&translation_len))->lkey;
1571 		} else {
1572 			lkey = spdk_mem_map_translate(device->map, (uint64_t)iovec->iov_base, &translation_len);
1573 		}
1574 		/* This is a very rare case that can occur when using DPDK version < 19.05 */
1575 		if (spdk_unlikely(translation_len < iovec->iov_len)) {
1576 			SPDK_ERRLOG("Data buffer split over multiple RDMA Memory Regions. Removing it from circulation.\n");
1577 			if (nvmf_rdma_replace_buffer(rgroup, &req->buffers[req->iovcnt]) == -ENOMEM) {
1578 				return -ENOMEM;
1579 			}
1580 			continue;
1581 		}
1582 
1583 		req->iovcnt++;
1584 
1585 		while (remaining_io_buffer_length && wr->num_sge < SPDK_NVMF_MAX_SGL_ENTRIES) {
1586 			sg_list = &wr->sg_list[wr->num_sge];
1587 			sg_list->addr = (uintptr_t)((char *) iovec->iov_base + offset);
1588 			sge_len = spdk_min(remaining_io_buffer_length, remaining_data_block);
1589 			sg_list->length = sge_len;
1590 			sg_list->lkey = lkey;
1591 			remaining_io_buffer_length -= sge_len;
1592 			remaining_data_block -= sge_len;
1593 			offset += sge_len;
1594 			wr->num_sge++;
1595 
1596 			if (remaining_data_block == 0) {
1597 				/* skip metadata */
1598 				offset += md_size;
1599 				/* Metadata that do not fit this IO buffer will be included in the next IO buffer */
1600 				remaining_io_buffer_length -= spdk_min(remaining_io_buffer_length, md_size);
1601 				remaining_data_block = data_block_size;
1602 			}
1603 
1604 			if (remaining_io_buffer_length == 0) {
1605 				/* By subtracting the size of the last IOV from the offset, we ensure that we skip
1606 				   the remaining metadata bits at the beginning of the next buffer */
1607 				offset -= iovec->iov_len;
1608 			}
1609 		}
1610 		remaining_length -= iovec->iov_len;
1611 	}
1612 
1613 	if (remaining_length) {
1614 		SPDK_ERRLOG("Not enough SG entries to hold data buffer\n");
1615 		return -EINVAL;
1616 	}
1617 
1618 	return 0;
1619 }
1620 
1621 static bool
1622 nvmf_rdma_get_lkey(struct spdk_nvmf_rdma_device *device, struct iovec *iov,
1623 		   uint32_t *_lkey)
1624 {
1625 	uint64_t	translation_len;
1626 	uint32_t	lkey;
1627 
1628 	translation_len = iov->iov_len;
1629 
1630 	if (!g_nvmf_hooks.get_rkey) {
1631 		lkey = ((struct ibv_mr *)spdk_mem_map_translate(device->map,
1632 				(uint64_t)iov->iov_base, &translation_len))->lkey;
1633 	} else {
1634 		lkey = spdk_mem_map_translate(device->map,
1635 					      (uint64_t)iov->iov_base, &translation_len);
1636 	}
1637 
1638 	if (spdk_unlikely(translation_len < iov->iov_len)) {
1639 		return false;
1640 	}
1641 
1642 	*_lkey = lkey;
1643 	return true;
1644 }
1645 
1646 static bool
1647 nvmf_rdma_fill_wr_sge(struct spdk_nvmf_rdma_device *device,
1648 		      struct spdk_nvmf_request *req, struct ibv_send_wr *wr)
1649 {
1650 	struct iovec	*iov = &req->iov[req->iovcnt];
1651 	struct ibv_sge	*sg_ele = &wr->sg_list[wr->num_sge];
1652 
1653 	if (spdk_unlikely(!nvmf_rdma_get_lkey(device, iov, &sg_ele->lkey))) {
1654 		/* This is a very rare case that can occur when using DPDK version < 19.05 */
1655 		SPDK_ERRLOG("Data buffer split over multiple RDMA Memory Regions. Removing it from circulation.\n");
1656 		return false;
1657 	}
1658 
1659 	sg_ele->addr = (uintptr_t)(iov->iov_base);
1660 	sg_ele->length = iov->iov_len;
1661 	wr->num_sge++;
1662 
1663 	return true;
1664 }
1665 
1666 static int
1667 nvmf_rdma_fill_buffers(struct spdk_nvmf_rdma_transport *rtransport,
1668 		       struct spdk_nvmf_rdma_poll_group *rgroup,
1669 		       struct spdk_nvmf_rdma_device *device,
1670 		       struct spdk_nvmf_request *req,
1671 		       struct ibv_send_wr *wr,
1672 		       uint32_t length)
1673 {
1674 	wr->num_sge = 0;
1675 	while (length) {
1676 		req->iov[req->iovcnt].iov_base = (void *)((uintptr_t)(req->buffers[req->iovcnt] +
1677 						 NVMF_DATA_BUFFER_MASK) &
1678 						 ~NVMF_DATA_BUFFER_MASK);
1679 		req->iov[req->iovcnt].iov_len  = spdk_min(length,
1680 						 rtransport->transport.opts.io_unit_size);
1681 		if (spdk_unlikely(!nvmf_rdma_fill_wr_sge(device, req, wr))) {
1682 			if (nvmf_rdma_replace_buffer(rgroup, &req->buffers[req->iovcnt]) == -ENOMEM) {
1683 				return -ENOMEM;
1684 			}
1685 			continue;
1686 		}
1687 
1688 		length -= req->iov[req->iovcnt].iov_len;
1689 		req->iovcnt++;
1690 	}
1691 
1692 	return 0;
1693 }
1694 
1695 static int
1696 spdk_nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1697 				 struct spdk_nvmf_rdma_device *device,
1698 				 struct spdk_nvmf_rdma_request *rdma_req,
1699 				 uint32_t length)
1700 {
1701 	struct spdk_nvmf_rdma_qpair		*rqpair;
1702 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1703 	struct spdk_nvmf_request		*req = &rdma_req->req;
1704 	struct ibv_send_wr			*wr = &rdma_req->data.wr;
1705 	int					rc = 0;
1706 
1707 	rqpair = SPDK_CONTAINEROF(req->qpair, struct spdk_nvmf_rdma_qpair, qpair);
1708 	rgroup = rqpair->poller->group;
1709 
1710 	if (spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport,
1711 					  length)) {
1712 		return -ENOMEM;
1713 	}
1714 
1715 	req->iovcnt = 0;
1716 
1717 	if (spdk_unlikely(rdma_req->dif_insert_or_strip)) {
1718 		rc = nvmf_rdma_fill_buffers_with_md_interleave(rtransport,
1719 				rgroup,
1720 				device,
1721 				&rdma_req->req,
1722 				wr,
1723 				length,
1724 				rdma_req->dif_ctx.block_size - rdma_req->dif_ctx.md_size,
1725 				rdma_req->dif_ctx.md_size);
1726 	} else {
1727 		rc = nvmf_rdma_fill_buffers(rtransport, rgroup, device, req, wr, length);
1728 	}
1729 	if (rc != 0) {
1730 		goto err_exit;
1731 	}
1732 
1733 	assert(req->iovcnt <= rqpair->max_send_sge);
1734 
1735 	req->data_from_pool = true;
1736 
1737 	return rc;
1738 
1739 err_exit:
1740 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1741 	memset(wr->sg_list, 0, sizeof(wr->sg_list[0]) * wr->num_sge);
1742 	wr->num_sge = 0;
1743 	req->iovcnt = 0;
1744 	return rc;
1745 }
1746 
1747 static int
1748 nvmf_rdma_request_fill_iovs_multi_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1749 				      struct spdk_nvmf_rdma_device *device,
1750 				      struct spdk_nvmf_rdma_request *rdma_req)
1751 {
1752 	struct spdk_nvmf_rdma_qpair		*rqpair;
1753 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1754 	struct ibv_send_wr			*current_wr;
1755 	struct spdk_nvmf_request		*req = &rdma_req->req;
1756 	struct spdk_nvme_sgl_descriptor		*inline_segment, *desc;
1757 	uint32_t				num_sgl_descriptors;
1758 	uint32_t				i;
1759 	int					rc;
1760 
1761 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1762 	rgroup = rqpair->poller->group;
1763 
1764 	inline_segment = &req->cmd->nvme_cmd.dptr.sgl1;
1765 	assert(inline_segment->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT);
1766 	assert(inline_segment->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET);
1767 
1768 	num_sgl_descriptors = inline_segment->unkeyed.length / sizeof(struct spdk_nvme_sgl_descriptor);
1769 	assert(num_sgl_descriptors <= SPDK_NVMF_MAX_SGL_ENTRIES);
1770 
1771 	if (nvmf_request_alloc_wrs(rtransport, rdma_req, num_sgl_descriptors - 1) != 0) {
1772 		return -ENOMEM;
1773 	}
1774 
1775 	/* The first WR must always be the embedded data WR. This is how we unwind them later. */
1776 	current_wr = &rdma_req->data.wr;
1777 	assert(current_wr != NULL);
1778 
1779 	req->iovcnt = 0;
1780 	req->length = 0;
1781 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1782 	for (i = 0; i < num_sgl_descriptors; i++) {
1783 		/* The descriptors must be keyed data block descriptors with an address, not an offset. */
1784 		if (spdk_unlikely(desc->generic.type != SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK ||
1785 				  desc->keyed.subtype != SPDK_NVME_SGL_SUBTYPE_ADDRESS)) {
1786 			rc = -EINVAL;
1787 			goto err_exit;
1788 		}
1789 
1790 		rc = spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport,
1791 						   desc->keyed.length);
1792 		if (rc != 0) {
1793 			goto err_exit;
1794 		}
1795 
1796 		current_wr->num_sge = 0;
1797 
1798 		rc = nvmf_rdma_fill_buffers(rtransport, rgroup, device, req, current_wr,
1799 					    desc->keyed.length);
1800 		if (rc != 0) {
1801 			rc = -ENOMEM;
1802 			goto err_exit;
1803 		}
1804 
1805 		req->length += desc->keyed.length;
1806 		current_wr->wr.rdma.rkey = desc->keyed.key;
1807 		current_wr->wr.rdma.remote_addr = desc->address;
1808 		current_wr = current_wr->next;
1809 		desc++;
1810 	}
1811 
1812 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1813 	/* Go back to the last descriptor in the list. */
1814 	desc--;
1815 	if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1816 		if (desc->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1817 			rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1818 			rdma_req->rsp.wr.imm_data = desc->keyed.key;
1819 		}
1820 	}
1821 #endif
1822 
1823 	rdma_req->num_outstanding_data_wr = num_sgl_descriptors;
1824 	req->data_from_pool = true;
1825 
1826 	return 0;
1827 
1828 err_exit:
1829 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1830 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1831 	return rc;
1832 }
1833 
1834 static int
1835 spdk_nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1836 				 struct spdk_nvmf_rdma_device *device,
1837 				 struct spdk_nvmf_rdma_request *rdma_req)
1838 {
1839 	struct spdk_nvme_cmd			*cmd;
1840 	struct spdk_nvme_cpl			*rsp;
1841 	struct spdk_nvme_sgl_descriptor		*sgl;
1842 	int					rc;
1843 	uint32_t				length;
1844 
1845 	cmd = &rdma_req->req.cmd->nvme_cmd;
1846 	rsp = &rdma_req->req.rsp->nvme_cpl;
1847 	sgl = &cmd->dptr.sgl1;
1848 
1849 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1850 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1851 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1852 
1853 		length = sgl->keyed.length;
1854 		if (length > rtransport->transport.opts.max_io_size) {
1855 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1856 				    length, rtransport->transport.opts.max_io_size);
1857 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1858 			return -1;
1859 		}
1860 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1861 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1862 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1863 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1864 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1865 			}
1866 		}
1867 #endif
1868 
1869 		/* fill request length and populate iovs */
1870 		rdma_req->req.length = length;
1871 
1872 		if (spdk_unlikely(rdma_req->dif_insert_or_strip)) {
1873 			rdma_req->orig_length = length;
1874 			length = spdk_dif_get_length_with_md(length, &rdma_req->dif_ctx);
1875 			rdma_req->elba_length = length;
1876 		}
1877 
1878 		if (spdk_nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req, length) < 0) {
1879 			/* No available buffers. Queue this request up. */
1880 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1881 			return 0;
1882 		}
1883 
1884 		/* backward compatible */
1885 		rdma_req->req.data = rdma_req->req.iov[0].iov_base;
1886 
1887 		/* rdma wr specifics */
1888 		rdma_req->data.wr.wr.rdma.rkey = sgl->keyed.key;
1889 		rdma_req->data.wr.wr.rdma.remote_addr = sgl->address;
1890 		if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1891 			rdma_req->data.wr.opcode = IBV_WR_RDMA_WRITE;
1892 			rdma_req->data.wr.next = &rdma_req->rsp.wr;
1893 			rdma_req->data.wr.send_flags &= ~IBV_SEND_SIGNALED;
1894 		} else if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1895 			rdma_req->data.wr.opcode = IBV_WR_RDMA_READ;
1896 			rdma_req->data.wr.next = NULL;
1897 			rdma_req->data.wr.send_flags |= IBV_SEND_SIGNALED;
1898 		}
1899 
1900 		/* set the number of outstanding data WRs for this request. */
1901 		rdma_req->num_outstanding_data_wr = 1;
1902 
1903 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1904 			      rdma_req->req.iovcnt);
1905 
1906 		return 0;
1907 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1908 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1909 		uint64_t offset = sgl->address;
1910 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1911 
1912 		SPDK_DEBUGLOG(SPDK_LOG_NVMF, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1913 			      offset, sgl->unkeyed.length);
1914 
1915 		if (offset > max_len) {
1916 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1917 				    offset, max_len);
1918 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1919 			return -1;
1920 		}
1921 		max_len -= (uint32_t)offset;
1922 
1923 		if (sgl->unkeyed.length > max_len) {
1924 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1925 				    sgl->unkeyed.length, max_len);
1926 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1927 			return -1;
1928 		}
1929 
1930 		rdma_req->num_outstanding_data_wr = 0;
1931 		rdma_req->req.data = rdma_req->recv->buf + offset;
1932 		rdma_req->req.data_from_pool = false;
1933 		rdma_req->req.length = sgl->unkeyed.length;
1934 
1935 		rdma_req->req.iov[0].iov_base = rdma_req->req.data;
1936 		rdma_req->req.iov[0].iov_len = rdma_req->req.length;
1937 		rdma_req->req.iovcnt = 1;
1938 
1939 		return 0;
1940 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT &&
1941 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1942 
1943 		rc = nvmf_rdma_request_fill_iovs_multi_sgl(rtransport, device, rdma_req);
1944 		if (rc == -ENOMEM) {
1945 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1946 			return 0;
1947 		} else if (rc == -EINVAL) {
1948 			SPDK_ERRLOG("Multi SGL element request length exceeds the max I/O size\n");
1949 			return -1;
1950 		}
1951 
1952 		/* backward compatible */
1953 		rdma_req->req.data = rdma_req->req.iov[0].iov_base;
1954 
1955 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1956 			      rdma_req->req.iovcnt);
1957 
1958 		return 0;
1959 	}
1960 
1961 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1962 		    sgl->generic.type, sgl->generic.subtype);
1963 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1964 	return -1;
1965 }
1966 
1967 static void
1968 nvmf_rdma_request_free(struct spdk_nvmf_rdma_request *rdma_req,
1969 		       struct spdk_nvmf_rdma_transport	*rtransport)
1970 {
1971 	struct spdk_nvmf_rdma_qpair		*rqpair;
1972 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1973 
1974 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1975 	if (rdma_req->req.data_from_pool) {
1976 		rgroup = rqpair->poller->group;
1977 
1978 		spdk_nvmf_request_free_buffers(&rdma_req->req, &rgroup->group, &rtransport->transport);
1979 	}
1980 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1981 	rdma_req->req.length = 0;
1982 	rdma_req->req.iovcnt = 0;
1983 	rdma_req->req.data = NULL;
1984 	rdma_req->rsp.wr.next = NULL;
1985 	rdma_req->data.wr.next = NULL;
1986 	rdma_req->dif_insert_or_strip = false;
1987 	rdma_req->elba_length = 0;
1988 	rdma_req->orig_length = 0;
1989 	memset(&rdma_req->dif_ctx, 0, sizeof(rdma_req->dif_ctx));
1990 	rqpair->qd--;
1991 
1992 	STAILQ_INSERT_HEAD(&rqpair->resources->free_queue, rdma_req, state_link);
1993 	rdma_req->state = RDMA_REQUEST_STATE_FREE;
1994 }
1995 
1996 static bool
1997 spdk_nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
1998 			       struct spdk_nvmf_rdma_request *rdma_req)
1999 {
2000 	struct spdk_nvmf_rdma_qpair	*rqpair;
2001 	struct spdk_nvmf_rdma_device	*device;
2002 	struct spdk_nvmf_rdma_poll_group *rgroup;
2003 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
2004 	int				rc;
2005 	struct spdk_nvmf_rdma_recv	*rdma_recv;
2006 	enum spdk_nvmf_rdma_request_state prev_state;
2007 	bool				progress = false;
2008 	int				data_posted;
2009 	uint32_t			num_blocks;
2010 
2011 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
2012 	device = rqpair->port->device;
2013 	rgroup = rqpair->poller->group;
2014 
2015 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
2016 
2017 	/* If the queue pair is in an error state, force the request to the completed state
2018 	 * to release resources. */
2019 	if (rqpair->ibv_state == IBV_QPS_ERR || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
2020 		if (rdma_req->state == RDMA_REQUEST_STATE_NEED_BUFFER) {
2021 			STAILQ_REMOVE(&rgroup->group.pending_buf_queue, &rdma_req->req, spdk_nvmf_request, buf_link);
2022 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING) {
2023 			STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2024 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING) {
2025 			STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2026 		}
2027 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2028 	}
2029 
2030 	/* The loop here is to allow for several back-to-back state changes. */
2031 	do {
2032 		prev_state = rdma_req->state;
2033 
2034 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p entering state %d\n", rdma_req, prev_state);
2035 
2036 		switch (rdma_req->state) {
2037 		case RDMA_REQUEST_STATE_FREE:
2038 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
2039 			 * to escape this state. */
2040 			break;
2041 		case RDMA_REQUEST_STATE_NEW:
2042 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
2043 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2044 			rdma_recv = rdma_req->recv;
2045 
2046 			/* The first element of the SGL is the NVMe command */
2047 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
2048 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
2049 
2050 			if (rqpair->ibv_state == IBV_QPS_ERR  || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
2051 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2052 				break;
2053 			}
2054 
2055 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&rdma_req->req, &rdma_req->dif_ctx))) {
2056 				rdma_req->dif_insert_or_strip = true;
2057 			}
2058 
2059 			/* The next state transition depends on the data transfer needs of this request. */
2060 			rdma_req->req.xfer = spdk_nvmf_rdma_request_get_xfer(rdma_req);
2061 
2062 			/* If no data to transfer, ready to execute. */
2063 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
2064 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
2065 				break;
2066 			}
2067 
2068 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
2069 			STAILQ_INSERT_TAIL(&rgroup->group.pending_buf_queue, &rdma_req->req, buf_link);
2070 			break;
2071 		case RDMA_REQUEST_STATE_NEED_BUFFER:
2072 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
2073 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2074 
2075 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
2076 
2077 			if (&rdma_req->req != STAILQ_FIRST(&rgroup->group.pending_buf_queue)) {
2078 				/* This request needs to wait in line to obtain a buffer */
2079 				break;
2080 			}
2081 
2082 			/* Try to get a data buffer */
2083 			rc = spdk_nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
2084 			if (rc < 0) {
2085 				STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2086 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
2087 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2088 				break;
2089 			}
2090 
2091 			if (!rdma_req->req.data) {
2092 				/* No buffers available. */
2093 				rgroup->stat.pending_data_buffer++;
2094 				break;
2095 			}
2096 
2097 			STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2098 
2099 			/* If data is transferring from host to controller and the data didn't
2100 			 * arrive using in capsule data, we need to do a transfer from the host.
2101 			 */
2102 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER &&
2103 			    rdma_req->req.data_from_pool) {
2104 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
2105 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
2106 				break;
2107 			}
2108 
2109 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
2110 			break;
2111 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
2112 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING, 0, 0,
2113 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2114 
2115 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_read_queue)) {
2116 				/* This request needs to wait in line to perform RDMA */
2117 				break;
2118 			}
2119 			if (rqpair->current_send_depth + rdma_req->num_outstanding_data_wr > rqpair->max_send_depth
2120 			    || rqpair->current_read_depth + rdma_req->num_outstanding_data_wr > rqpair->max_read_depth) {
2121 				/* We can only have so many WRs outstanding. we have to wait until some finish. */
2122 				rqpair->poller->stat.pending_rdma_read++;
2123 				break;
2124 			}
2125 
2126 			/* We have already verified that this request is the head of the queue. */
2127 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_read_queue, state_link);
2128 
2129 			rc = request_transfer_in(&rdma_req->req);
2130 			if (!rc) {
2131 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
2132 			} else {
2133 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
2134 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2135 			}
2136 			break;
2137 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2138 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2139 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2140 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
2141 			 * to escape this state. */
2142 			break;
2143 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
2144 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
2145 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2146 
2147 			if (spdk_unlikely(rdma_req->dif_insert_or_strip)) {
2148 				if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2149 					/* generate DIF for write operation */
2150 					num_blocks = SPDK_CEIL_DIV(rdma_req->elba_length, rdma_req->dif_ctx.block_size);
2151 					assert(num_blocks > 0);
2152 
2153 					rc = spdk_dif_generate(rdma_req->req.iov, rdma_req->req.iovcnt,
2154 							       num_blocks, &rdma_req->dif_ctx);
2155 					if (rc != 0) {
2156 						SPDK_ERRLOG("DIF generation failed\n");
2157 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2158 						spdk_nvmf_rdma_start_disconnect(rqpair);
2159 						break;
2160 					}
2161 				}
2162 
2163 				assert(rdma_req->elba_length >= rdma_req->req.length);
2164 				/* set extended length before IO operation */
2165 				rdma_req->req.length = rdma_req->elba_length;
2166 			}
2167 
2168 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
2169 			spdk_nvmf_request_exec(&rdma_req->req);
2170 			break;
2171 		case RDMA_REQUEST_STATE_EXECUTING:
2172 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
2173 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2174 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
2175 			 * to escape this state. */
2176 			break;
2177 		case RDMA_REQUEST_STATE_EXECUTED:
2178 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
2179 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2180 			if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2181 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_write_queue, rdma_req, state_link);
2182 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING;
2183 			} else {
2184 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2185 			}
2186 			if (spdk_unlikely(rdma_req->dif_insert_or_strip)) {
2187 				/* restore the original length */
2188 				rdma_req->req.length = rdma_req->orig_length;
2189 
2190 				if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2191 					struct spdk_dif_error error_blk;
2192 
2193 					num_blocks = SPDK_CEIL_DIV(rdma_req->elba_length, rdma_req->dif_ctx.block_size);
2194 
2195 					rc = spdk_dif_verify(rdma_req->req.iov, rdma_req->req.iovcnt, num_blocks, &rdma_req->dif_ctx,
2196 							     &error_blk);
2197 					if (rc) {
2198 						struct spdk_nvme_cpl *rsp = &rdma_req->req.rsp->nvme_cpl;
2199 
2200 						SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n", error_blk.err_type,
2201 							    error_blk.err_offset);
2202 						rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2203 						rsp->status.sc = spdk_nvmf_rdma_dif_error_to_compl_status(error_blk.err_type);
2204 						rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2205 						STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2206 					}
2207 				}
2208 			}
2209 			break;
2210 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
2211 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING, 0, 0,
2212 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2213 
2214 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_write_queue)) {
2215 				/* This request needs to wait in line to perform RDMA */
2216 				break;
2217 			}
2218 			if ((rqpair->current_send_depth + rdma_req->num_outstanding_data_wr + 1) >
2219 			    rqpair->max_send_depth) {
2220 				/* We can only have so many WRs outstanding. we have to wait until some finish.
2221 				 * +1 since each request has an additional wr in the resp. */
2222 				rqpair->poller->stat.pending_rdma_write++;
2223 				break;
2224 			}
2225 
2226 			/* We have already verified that this request is the head of the queue. */
2227 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_write_queue, state_link);
2228 
2229 			/* The data transfer will be kicked off from
2230 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
2231 			 */
2232 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2233 			break;
2234 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
2235 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
2236 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2237 			rc = request_transfer_out(&rdma_req->req, &data_posted);
2238 			assert(rc == 0); /* No good way to handle this currently */
2239 			if (rc) {
2240 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2241 			} else {
2242 				rdma_req->state = data_posted ? RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
2243 						  RDMA_REQUEST_STATE_COMPLETING;
2244 			}
2245 			break;
2246 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2247 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2248 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2249 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2250 			 * to escape this state. */
2251 			break;
2252 		case RDMA_REQUEST_STATE_COMPLETING:
2253 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
2254 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2255 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2256 			 * to escape this state. */
2257 			break;
2258 		case RDMA_REQUEST_STATE_COMPLETED:
2259 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
2260 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2261 
2262 			rqpair->poller->stat.request_latency += spdk_get_ticks() - rdma_req->receive_tsc;
2263 			nvmf_rdma_request_free(rdma_req, rtransport);
2264 			break;
2265 		case RDMA_REQUEST_NUM_STATES:
2266 		default:
2267 			assert(0);
2268 			break;
2269 		}
2270 
2271 		if (rdma_req->state != prev_state) {
2272 			progress = true;
2273 		}
2274 	} while (rdma_req->state != prev_state);
2275 
2276 	return progress;
2277 }
2278 
2279 /* Public API callbacks begin here */
2280 
2281 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
2282 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
2283 #define SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH 4096
2284 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
2285 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2286 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
2287 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
2288 #define SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS 4095
2289 #define SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE 32
2290 #define SPDK_NVMF_RDMA_DEFAULT_NO_SRQ false
2291 #define SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP false
2292 
2293 static void
2294 spdk_nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
2295 {
2296 	opts->max_queue_depth =		SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
2297 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2298 	opts->in_capsule_data_size =	SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
2299 	opts->max_io_size =		SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
2300 	opts->io_unit_size =		SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE;
2301 	opts->max_aq_depth =		SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
2302 	opts->num_shared_buffers =	SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS;
2303 	opts->buf_cache_size =		SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE;
2304 	opts->max_srq_depth =		SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH;
2305 	opts->no_srq =			SPDK_NVMF_RDMA_DEFAULT_NO_SRQ;
2306 	opts->dif_insert_or_strip =	SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP;
2307 }
2308 
2309 const struct spdk_mem_map_ops g_nvmf_rdma_map_ops = {
2310 	.notify_cb = spdk_nvmf_rdma_mem_notify,
2311 	.are_contiguous = spdk_nvmf_rdma_check_contiguous_entries
2312 };
2313 
2314 static int spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport);
2315 
2316 static struct spdk_nvmf_transport *
2317 spdk_nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
2318 {
2319 	int rc;
2320 	struct spdk_nvmf_rdma_transport *rtransport;
2321 	struct spdk_nvmf_rdma_device	*device, *tmp;
2322 	struct ibv_context		**contexts;
2323 	uint32_t			i;
2324 	int				flag;
2325 	uint32_t			sge_count;
2326 	uint32_t			min_shared_buffers;
2327 	int				max_device_sge = SPDK_NVMF_MAX_SGL_ENTRIES;
2328 	pthread_mutexattr_t		attr;
2329 
2330 	rtransport = calloc(1, sizeof(*rtransport));
2331 	if (!rtransport) {
2332 		return NULL;
2333 	}
2334 
2335 	if (pthread_mutexattr_init(&attr)) {
2336 		SPDK_ERRLOG("pthread_mutexattr_init() failed\n");
2337 		free(rtransport);
2338 		return NULL;
2339 	}
2340 
2341 	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) {
2342 		SPDK_ERRLOG("pthread_mutexattr_settype() failed\n");
2343 		pthread_mutexattr_destroy(&attr);
2344 		free(rtransport);
2345 		return NULL;
2346 	}
2347 
2348 	if (pthread_mutex_init(&rtransport->lock, &attr)) {
2349 		SPDK_ERRLOG("pthread_mutex_init() failed\n");
2350 		pthread_mutexattr_destroy(&attr);
2351 		free(rtransport);
2352 		return NULL;
2353 	}
2354 
2355 	pthread_mutexattr_destroy(&attr);
2356 
2357 	TAILQ_INIT(&rtransport->devices);
2358 	TAILQ_INIT(&rtransport->ports);
2359 	TAILQ_INIT(&rtransport->poll_groups);
2360 
2361 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
2362 
2363 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** RDMA Transport Init ***\n"
2364 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
2365 		     "  max_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
2366 		     "  in_capsule_data_size=%d, max_aq_depth=%d,\n"
2367 		     "  num_shared_buffers=%d, max_srq_depth=%d, no_srq=%d\n",
2368 		     opts->max_queue_depth,
2369 		     opts->max_io_size,
2370 		     opts->max_qpairs_per_ctrlr,
2371 		     opts->io_unit_size,
2372 		     opts->in_capsule_data_size,
2373 		     opts->max_aq_depth,
2374 		     opts->num_shared_buffers,
2375 		     opts->max_srq_depth,
2376 		     opts->no_srq);
2377 
2378 	/* I/O unit size cannot be larger than max I/O size */
2379 	if (opts->io_unit_size > opts->max_io_size) {
2380 		opts->io_unit_size = opts->max_io_size;
2381 	}
2382 
2383 	if (opts->num_shared_buffers < (SPDK_NVMF_MAX_SGL_ENTRIES * 2)) {
2384 		SPDK_ERRLOG("The number of shared data buffers (%d) is less than"
2385 			    "the minimum number required to guarantee that forward progress can be made (%d)\n",
2386 			    opts->num_shared_buffers, (SPDK_NVMF_MAX_SGL_ENTRIES * 2));
2387 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2388 		return NULL;
2389 	}
2390 
2391 	min_shared_buffers = spdk_thread_get_count() * opts->buf_cache_size;
2392 	if (min_shared_buffers > opts->num_shared_buffers) {
2393 		SPDK_ERRLOG("There are not enough buffers to satisfy"
2394 			    "per-poll group caches for each thread. (%" PRIu32 ")"
2395 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
2396 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
2397 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2398 		return NULL;
2399 	}
2400 
2401 	sge_count = opts->max_io_size / opts->io_unit_size;
2402 	if (sge_count > NVMF_DEFAULT_TX_SGE) {
2403 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
2404 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2405 		return NULL;
2406 	}
2407 
2408 	rtransport->event_channel = rdma_create_event_channel();
2409 	if (rtransport->event_channel == NULL) {
2410 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
2411 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2412 		return NULL;
2413 	}
2414 
2415 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
2416 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2417 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
2418 			    rtransport->event_channel->fd, spdk_strerror(errno));
2419 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2420 		return NULL;
2421 	}
2422 
2423 	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data",
2424 				   opts->max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES,
2425 				   sizeof(struct spdk_nvmf_rdma_request_data),
2426 				   SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
2427 				   SPDK_ENV_SOCKET_ID_ANY);
2428 	if (!rtransport->data_wr_pool) {
2429 		SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");
2430 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2431 		return NULL;
2432 	}
2433 
2434 	contexts = rdma_get_devices(NULL);
2435 	if (contexts == NULL) {
2436 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2437 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2438 		return NULL;
2439 	}
2440 
2441 	i = 0;
2442 	rc = 0;
2443 	while (contexts[i] != NULL) {
2444 		device = calloc(1, sizeof(*device));
2445 		if (!device) {
2446 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
2447 			rc = -ENOMEM;
2448 			break;
2449 		}
2450 		device->context = contexts[i];
2451 		rc = ibv_query_device(device->context, &device->attr);
2452 		if (rc < 0) {
2453 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2454 			free(device);
2455 			break;
2456 
2457 		}
2458 
2459 		max_device_sge = spdk_min(max_device_sge, device->attr.max_sge);
2460 
2461 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2462 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
2463 			SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
2464 			SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
2465 		}
2466 
2467 		/**
2468 		 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
2469 		 * The Soft-RoCE RXE driver does not currently support send with invalidate,
2470 		 * but incorrectly reports that it does. There are changes making their way
2471 		 * through the kernel now that will enable this feature. When they are merged,
2472 		 * we can conditionally enable this feature.
2473 		 *
2474 		 * TODO: enable this for versions of the kernel rxe driver that support it.
2475 		 */
2476 		if (device->attr.vendor_id == 0) {
2477 			device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
2478 		}
2479 #endif
2480 
2481 		/* set up device context async ev fd as NON_BLOCKING */
2482 		flag = fcntl(device->context->async_fd, F_GETFL);
2483 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
2484 		if (rc < 0) {
2485 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
2486 			free(device);
2487 			break;
2488 		}
2489 
2490 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
2491 		i++;
2492 
2493 		if (g_nvmf_hooks.get_ibv_pd) {
2494 			device->pd = g_nvmf_hooks.get_ibv_pd(NULL, device->context);
2495 		} else {
2496 			device->pd = ibv_alloc_pd(device->context);
2497 		}
2498 
2499 		if (!device->pd) {
2500 			SPDK_ERRLOG("Unable to allocate protection domain.\n");
2501 			rc = -ENOMEM;
2502 			break;
2503 		}
2504 
2505 		assert(device->map == NULL);
2506 
2507 		device->map = spdk_mem_map_alloc(0, &g_nvmf_rdma_map_ops, device->pd);
2508 		if (!device->map) {
2509 			SPDK_ERRLOG("Unable to allocate memory map for listen address\n");
2510 			rc = -ENOMEM;
2511 			break;
2512 		}
2513 
2514 		assert(device->map != NULL);
2515 		assert(device->pd != NULL);
2516 	}
2517 	rdma_free_devices(contexts);
2518 
2519 	if (opts->io_unit_size * max_device_sge < opts->max_io_size) {
2520 		/* divide and round up. */
2521 		opts->io_unit_size = (opts->max_io_size + max_device_sge - 1) / max_device_sge;
2522 
2523 		/* round up to the nearest 4k. */
2524 		opts->io_unit_size = (opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT - 1) & ~NVMF_DATA_BUFFER_MASK;
2525 
2526 		opts->io_unit_size = spdk_max(opts->io_unit_size, SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
2527 		SPDK_NOTICELOG("Adjusting the io unit size to fit the device's maximum I/O size. New I/O unit size %u\n",
2528 			       opts->io_unit_size);
2529 	}
2530 
2531 	if (rc < 0) {
2532 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2533 		return NULL;
2534 	}
2535 
2536 	/* Set up poll descriptor array to monitor events from RDMA and IB
2537 	 * in a single poll syscall
2538 	 */
2539 	rtransport->npoll_fds = i + 1;
2540 	i = 0;
2541 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
2542 	if (rtransport->poll_fds == NULL) {
2543 		SPDK_ERRLOG("poll_fds allocation failed\n");
2544 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2545 		return NULL;
2546 	}
2547 
2548 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
2549 	rtransport->poll_fds[i++].events = POLLIN;
2550 
2551 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2552 		rtransport->poll_fds[i].fd = device->context->async_fd;
2553 		rtransport->poll_fds[i++].events = POLLIN;
2554 	}
2555 
2556 	return &rtransport->transport;
2557 }
2558 
2559 static int
2560 spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport)
2561 {
2562 	struct spdk_nvmf_rdma_transport	*rtransport;
2563 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
2564 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
2565 
2566 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2567 
2568 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
2569 		TAILQ_REMOVE(&rtransport->ports, port, link);
2570 		rdma_destroy_id(port->id);
2571 		free(port);
2572 	}
2573 
2574 	if (rtransport->poll_fds != NULL) {
2575 		free(rtransport->poll_fds);
2576 	}
2577 
2578 	if (rtransport->event_channel != NULL) {
2579 		rdma_destroy_event_channel(rtransport->event_channel);
2580 	}
2581 
2582 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
2583 		TAILQ_REMOVE(&rtransport->devices, device, link);
2584 		if (device->map) {
2585 			spdk_mem_map_free(&device->map);
2586 		}
2587 		if (device->pd) {
2588 			if (!g_nvmf_hooks.get_ibv_pd) {
2589 				ibv_dealloc_pd(device->pd);
2590 			}
2591 		}
2592 		free(device);
2593 	}
2594 
2595 	if (rtransport->data_wr_pool != NULL) {
2596 		if (spdk_mempool_count(rtransport->data_wr_pool) !=
2597 		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {
2598 			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",
2599 				    spdk_mempool_count(rtransport->data_wr_pool),
2600 				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);
2601 		}
2602 	}
2603 
2604 	spdk_mempool_free(rtransport->data_wr_pool);
2605 
2606 	pthread_mutex_destroy(&rtransport->lock);
2607 	free(rtransport);
2608 
2609 	return 0;
2610 }
2611 
2612 static int
2613 spdk_nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2614 			       struct spdk_nvme_transport_id *trid,
2615 			       bool peer);
2616 
2617 static int
2618 spdk_nvmf_rdma_listen(struct spdk_nvmf_transport *transport,
2619 		      const struct spdk_nvme_transport_id *trid)
2620 {
2621 	struct spdk_nvmf_rdma_transport	*rtransport;
2622 	struct spdk_nvmf_rdma_device	*device;
2623 	struct spdk_nvmf_rdma_port	*port_tmp, *port;
2624 	struct addrinfo			*res;
2625 	struct addrinfo			hints;
2626 	int				family;
2627 	int				rc;
2628 
2629 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2630 
2631 	port = calloc(1, sizeof(*port));
2632 	if (!port) {
2633 		return -ENOMEM;
2634 	}
2635 
2636 	/* Selectively copy the trid. Things like NQN don't matter here - that
2637 	 * mapping is enforced elsewhere.
2638 	 */
2639 	port->trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
2640 	port->trid.adrfam = trid->adrfam;
2641 	snprintf(port->trid.traddr, sizeof(port->trid.traddr), "%s", trid->traddr);
2642 	snprintf(port->trid.trsvcid, sizeof(port->trid.trsvcid), "%s", trid->trsvcid);
2643 
2644 	switch (port->trid.adrfam) {
2645 	case SPDK_NVMF_ADRFAM_IPV4:
2646 		family = AF_INET;
2647 		break;
2648 	case SPDK_NVMF_ADRFAM_IPV6:
2649 		family = AF_INET6;
2650 		break;
2651 	default:
2652 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", port->trid.adrfam);
2653 		free(port);
2654 		return -EINVAL;
2655 	}
2656 
2657 	memset(&hints, 0, sizeof(hints));
2658 	hints.ai_family = family;
2659 	hints.ai_flags = AI_NUMERICSERV;
2660 	hints.ai_socktype = SOCK_STREAM;
2661 	hints.ai_protocol = 0;
2662 
2663 	rc = getaddrinfo(port->trid.traddr, port->trid.trsvcid, &hints, &res);
2664 	if (rc) {
2665 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
2666 		free(port);
2667 		return -EINVAL;
2668 	}
2669 
2670 	pthread_mutex_lock(&rtransport->lock);
2671 	assert(rtransport->event_channel != NULL);
2672 	TAILQ_FOREACH(port_tmp, &rtransport->ports, link) {
2673 		if (spdk_nvme_transport_id_compare(&port_tmp->trid, &port->trid) == 0) {
2674 			port_tmp->ref++;
2675 			freeaddrinfo(res);
2676 			free(port);
2677 			/* Already listening at this address */
2678 			pthread_mutex_unlock(&rtransport->lock);
2679 			return 0;
2680 		}
2681 	}
2682 
2683 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
2684 	if (rc < 0) {
2685 		SPDK_ERRLOG("rdma_create_id() failed\n");
2686 		freeaddrinfo(res);
2687 		free(port);
2688 		pthread_mutex_unlock(&rtransport->lock);
2689 		return rc;
2690 	}
2691 
2692 	rc = rdma_bind_addr(port->id, res->ai_addr);
2693 	freeaddrinfo(res);
2694 
2695 	if (rc < 0) {
2696 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
2697 		rdma_destroy_id(port->id);
2698 		free(port);
2699 		pthread_mutex_unlock(&rtransport->lock);
2700 		return rc;
2701 	}
2702 
2703 	if (!port->id->verbs) {
2704 		SPDK_ERRLOG("ibv_context is null\n");
2705 		rdma_destroy_id(port->id);
2706 		free(port);
2707 		pthread_mutex_unlock(&rtransport->lock);
2708 		return -1;
2709 	}
2710 
2711 	rc = rdma_listen(port->id, 10); /* 10 = backlog */
2712 	if (rc < 0) {
2713 		SPDK_ERRLOG("rdma_listen() failed\n");
2714 		rdma_destroy_id(port->id);
2715 		free(port);
2716 		pthread_mutex_unlock(&rtransport->lock);
2717 		return rc;
2718 	}
2719 
2720 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2721 		if (device->context == port->id->verbs) {
2722 			port->device = device;
2723 			break;
2724 		}
2725 	}
2726 	if (!port->device) {
2727 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
2728 			    port->id->verbs);
2729 		rdma_destroy_id(port->id);
2730 		free(port);
2731 		pthread_mutex_unlock(&rtransport->lock);
2732 		return -EINVAL;
2733 	}
2734 
2735 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** NVMf Target Listening on %s port %d ***\n",
2736 		     port->trid.traddr, ntohs(rdma_get_src_port(port->id)));
2737 
2738 	port->ref = 1;
2739 
2740 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
2741 	pthread_mutex_unlock(&rtransport->lock);
2742 
2743 	return 0;
2744 }
2745 
2746 static int
2747 spdk_nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
2748 			   const struct spdk_nvme_transport_id *_trid)
2749 {
2750 	struct spdk_nvmf_rdma_transport *rtransport;
2751 	struct spdk_nvmf_rdma_port *port, *tmp;
2752 	struct spdk_nvme_transport_id trid = {};
2753 
2754 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2755 
2756 	/* Selectively copy the trid. Things like NQN don't matter here - that
2757 	 * mapping is enforced elsewhere.
2758 	 */
2759 	trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
2760 	trid.adrfam = _trid->adrfam;
2761 	snprintf(trid.traddr, sizeof(port->trid.traddr), "%s", _trid->traddr);
2762 	snprintf(trid.trsvcid, sizeof(port->trid.trsvcid), "%s", _trid->trsvcid);
2763 
2764 	pthread_mutex_lock(&rtransport->lock);
2765 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
2766 		if (spdk_nvme_transport_id_compare(&port->trid, &trid) == 0) {
2767 			assert(port->ref > 0);
2768 			port->ref--;
2769 			if (port->ref == 0) {
2770 				TAILQ_REMOVE(&rtransport->ports, port, link);
2771 				rdma_destroy_id(port->id);
2772 				free(port);
2773 			}
2774 			break;
2775 		}
2776 	}
2777 
2778 	pthread_mutex_unlock(&rtransport->lock);
2779 	return 0;
2780 }
2781 
2782 static void
2783 spdk_nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
2784 				     struct spdk_nvmf_rdma_qpair *rqpair, bool drain)
2785 {
2786 	struct spdk_nvmf_request *req, *tmp;
2787 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
2788 	struct spdk_nvmf_rdma_resources *resources;
2789 
2790 	/* We process I/O in the data transfer pending queue at the highest priority. RDMA reads first */
2791 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_read_queue, state_link, req_tmp) {
2792 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2793 			break;
2794 		}
2795 	}
2796 
2797 	/* Then RDMA writes since reads have stronger restrictions than writes */
2798 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_write_queue, state_link, req_tmp) {
2799 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2800 			break;
2801 		}
2802 	}
2803 
2804 	/* The second highest priority is I/O waiting on memory buffers. */
2805 	STAILQ_FOREACH_SAFE(req, &rqpair->poller->group->group.pending_buf_queue, buf_link, tmp) {
2806 		rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
2807 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2808 			break;
2809 		}
2810 	}
2811 
2812 	resources = rqpair->resources;
2813 	while (!STAILQ_EMPTY(&resources->free_queue) && !STAILQ_EMPTY(&resources->incoming_queue)) {
2814 		rdma_req = STAILQ_FIRST(&resources->free_queue);
2815 		STAILQ_REMOVE_HEAD(&resources->free_queue, state_link);
2816 		rdma_req->recv = STAILQ_FIRST(&resources->incoming_queue);
2817 		STAILQ_REMOVE_HEAD(&resources->incoming_queue, link);
2818 
2819 		if (rqpair->srq != NULL) {
2820 			rdma_req->req.qpair = &rdma_req->recv->qpair->qpair;
2821 			rdma_req->recv->qpair->qd++;
2822 		} else {
2823 			rqpair->qd++;
2824 		}
2825 
2826 		rdma_req->receive_tsc = rdma_req->recv->receive_tsc;
2827 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
2828 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false) {
2829 			break;
2830 		}
2831 	}
2832 	if (!STAILQ_EMPTY(&resources->incoming_queue) && STAILQ_EMPTY(&resources->free_queue)) {
2833 		rqpair->poller->stat.pending_free_request++;
2834 	}
2835 }
2836 
2837 static void
2838 _nvmf_rdma_qpair_disconnect(void *ctx)
2839 {
2840 	struct spdk_nvmf_qpair *qpair = ctx;
2841 
2842 	spdk_nvmf_qpair_disconnect(qpair, NULL, NULL);
2843 }
2844 
2845 static void
2846 _nvmf_rdma_try_disconnect(void *ctx)
2847 {
2848 	struct spdk_nvmf_qpair *qpair = ctx;
2849 	struct spdk_nvmf_poll_group *group;
2850 
2851 	/* Read the group out of the qpair. This is normally set and accessed only from
2852 	 * the thread that created the group. Here, we're not on that thread necessarily.
2853 	 * The data member qpair->group begins it's life as NULL and then is assigned to
2854 	 * a pointer and never changes. So fortunately reading this and checking for
2855 	 * non-NULL is thread safe in the x86_64 memory model. */
2856 	group = qpair->group;
2857 
2858 	if (group == NULL) {
2859 		/* The qpair hasn't been assigned to a group yet, so we can't
2860 		 * process a disconnect. Send a message to ourself and try again. */
2861 		spdk_thread_send_msg(spdk_get_thread(), _nvmf_rdma_try_disconnect, qpair);
2862 		return;
2863 	}
2864 
2865 	spdk_thread_send_msg(group->thread, _nvmf_rdma_qpair_disconnect, qpair);
2866 }
2867 
2868 static inline void
2869 spdk_nvmf_rdma_start_disconnect(struct spdk_nvmf_rdma_qpair *rqpair)
2870 {
2871 	if (__sync_bool_compare_and_swap(&rqpair->disconnect_started, false, true)) {
2872 		_nvmf_rdma_try_disconnect(&rqpair->qpair);
2873 	}
2874 }
2875 
2876 static void nvmf_rdma_destroy_drained_qpair(void *ctx)
2877 {
2878 	struct spdk_nvmf_rdma_qpair *rqpair = ctx;
2879 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
2880 			struct spdk_nvmf_rdma_transport, transport);
2881 
2882 	/* In non SRQ path, we will reach rqpair->max_queue_depth. In SRQ path, we will get the last_wqe event. */
2883 	if (rqpair->current_send_depth != 0) {
2884 		return;
2885 	}
2886 
2887 	if (rqpair->srq == NULL && rqpair->current_recv_depth != rqpair->max_queue_depth) {
2888 		return;
2889 	}
2890 
2891 	if (rqpair->srq != NULL && rqpair->last_wqe_reached == false) {
2892 		return;
2893 	}
2894 
2895 	spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
2896 
2897 	/* Qpair will be destroyed after nvmf layer closes this qpair */
2898 	if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ERROR) {
2899 		return;
2900 	}
2901 
2902 	spdk_nvmf_rdma_qpair_destroy(rqpair);
2903 }
2904 
2905 
2906 static int
2907 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
2908 {
2909 	struct spdk_nvmf_qpair		*qpair;
2910 	struct spdk_nvmf_rdma_qpair	*rqpair;
2911 
2912 	if (evt->id == NULL) {
2913 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
2914 		return -1;
2915 	}
2916 
2917 	qpair = evt->id->context;
2918 	if (qpair == NULL) {
2919 		SPDK_ERRLOG("disconnect request: no active connection\n");
2920 		return -1;
2921 	}
2922 
2923 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2924 
2925 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair->cm_id, 0);
2926 
2927 	spdk_nvmf_rdma_update_ibv_state(rqpair);
2928 
2929 	spdk_nvmf_rdma_start_disconnect(rqpair);
2930 
2931 	return 0;
2932 }
2933 
2934 #ifdef DEBUG
2935 static const char *CM_EVENT_STR[] = {
2936 	"RDMA_CM_EVENT_ADDR_RESOLVED",
2937 	"RDMA_CM_EVENT_ADDR_ERROR",
2938 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
2939 	"RDMA_CM_EVENT_ROUTE_ERROR",
2940 	"RDMA_CM_EVENT_CONNECT_REQUEST",
2941 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
2942 	"RDMA_CM_EVENT_CONNECT_ERROR",
2943 	"RDMA_CM_EVENT_UNREACHABLE",
2944 	"RDMA_CM_EVENT_REJECTED",
2945 	"RDMA_CM_EVENT_ESTABLISHED",
2946 	"RDMA_CM_EVENT_DISCONNECTED",
2947 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
2948 	"RDMA_CM_EVENT_MULTICAST_JOIN",
2949 	"RDMA_CM_EVENT_MULTICAST_ERROR",
2950 	"RDMA_CM_EVENT_ADDR_CHANGE",
2951 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
2952 };
2953 #endif /* DEBUG */
2954 
2955 static void
2956 nvmf_rdma_handle_last_wqe_reached(void *ctx)
2957 {
2958 	struct spdk_nvmf_rdma_qpair *rqpair = ctx;
2959 	rqpair->last_wqe_reached = true;
2960 
2961 	nvmf_rdma_destroy_drained_qpair(rqpair);
2962 }
2963 
2964 static void
2965 spdk_nvmf_process_cm_event(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
2966 {
2967 	struct spdk_nvmf_rdma_transport *rtransport;
2968 	struct rdma_cm_event		*event;
2969 	int				rc;
2970 
2971 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2972 
2973 	if (rtransport->event_channel == NULL) {
2974 		return;
2975 	}
2976 
2977 	while (1) {
2978 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
2979 		if (rc == 0) {
2980 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
2981 
2982 			spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
2983 
2984 			switch (event->event) {
2985 			case RDMA_CM_EVENT_ADDR_RESOLVED:
2986 			case RDMA_CM_EVENT_ADDR_ERROR:
2987 			case RDMA_CM_EVENT_ROUTE_RESOLVED:
2988 			case RDMA_CM_EVENT_ROUTE_ERROR:
2989 				/* No action required. The target never attempts to resolve routes. */
2990 				break;
2991 			case RDMA_CM_EVENT_CONNECT_REQUEST:
2992 				rc = nvmf_rdma_connect(transport, event, cb_fn);
2993 				if (rc < 0) {
2994 					SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
2995 					break;
2996 				}
2997 				break;
2998 			case RDMA_CM_EVENT_CONNECT_RESPONSE:
2999 				/* The target never initiates a new connection. So this will not occur. */
3000 				break;
3001 			case RDMA_CM_EVENT_CONNECT_ERROR:
3002 				/* Can this happen? The docs say it can, but not sure what causes it. */
3003 				break;
3004 			case RDMA_CM_EVENT_UNREACHABLE:
3005 			case RDMA_CM_EVENT_REJECTED:
3006 				/* These only occur on the client side. */
3007 				break;
3008 			case RDMA_CM_EVENT_ESTABLISHED:
3009 				/* TODO: Should we be waiting for this event anywhere? */
3010 				break;
3011 			case RDMA_CM_EVENT_DISCONNECTED:
3012 			case RDMA_CM_EVENT_DEVICE_REMOVAL:
3013 				rc = nvmf_rdma_disconnect(event);
3014 				if (rc < 0) {
3015 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
3016 					break;
3017 				}
3018 				break;
3019 			case RDMA_CM_EVENT_MULTICAST_JOIN:
3020 			case RDMA_CM_EVENT_MULTICAST_ERROR:
3021 				/* Multicast is not used */
3022 				break;
3023 			case RDMA_CM_EVENT_ADDR_CHANGE:
3024 				/* Not utilizing this event */
3025 				break;
3026 			case RDMA_CM_EVENT_TIMEWAIT_EXIT:
3027 				/* For now, do nothing. The target never re-uses queue pairs. */
3028 				break;
3029 			default:
3030 				SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
3031 				break;
3032 			}
3033 
3034 			rdma_ack_cm_event(event);
3035 		} else {
3036 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
3037 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
3038 			}
3039 			break;
3040 		}
3041 	}
3042 }
3043 
3044 static void
3045 spdk_nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
3046 {
3047 	int				rc;
3048 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
3049 	struct ibv_async_event		event;
3050 	enum ibv_qp_state		state;
3051 
3052 	rc = ibv_get_async_event(device->context, &event);
3053 
3054 	if (rc) {
3055 		SPDK_ERRLOG("Failed to get async_event (%d): %s\n",
3056 			    errno, spdk_strerror(errno));
3057 		return;
3058 	}
3059 
3060 	switch (event.event_type) {
3061 	case IBV_EVENT_QP_FATAL:
3062 		rqpair = event.element.qp->qp_context;
3063 		SPDK_ERRLOG("Fatal event received for rqpair %p\n", rqpair);
3064 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3065 				  (uintptr_t)rqpair->cm_id, event.event_type);
3066 		spdk_nvmf_rdma_update_ibv_state(rqpair);
3067 		spdk_nvmf_rdma_start_disconnect(rqpair);
3068 		break;
3069 	case IBV_EVENT_QP_LAST_WQE_REACHED:
3070 		/* This event only occurs for shared receive queues. */
3071 		rqpair = event.element.qp->qp_context;
3072 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Last WQE reached event received for rqpair %p\n", rqpair);
3073 		/* This must be handled on the polling thread if it exists. Otherwise the timeout will catch it. */
3074 		if (rqpair->qpair.group) {
3075 			spdk_thread_send_msg(rqpair->qpair.group->thread, nvmf_rdma_handle_last_wqe_reached, rqpair);
3076 		} else {
3077 			SPDK_ERRLOG("Unable to destroy the qpair %p since it does not have a poll group.\n", rqpair);
3078 			rqpair->last_wqe_reached = true;
3079 		}
3080 
3081 		break;
3082 	case IBV_EVENT_SQ_DRAINED:
3083 		/* This event occurs frequently in both error and non-error states.
3084 		 * Check if the qpair is in an error state before sending a message.
3085 		 * Note that we're not on the correct thread to access the qpair, but
3086 		 * the operations that the below calls make all happen to be thread
3087 		 * safe. */
3088 		rqpair = event.element.qp->qp_context;
3089 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Last sq drained event received for rqpair %p\n", rqpair);
3090 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3091 				  (uintptr_t)rqpair->cm_id, event.event_type);
3092 		state = spdk_nvmf_rdma_update_ibv_state(rqpair);
3093 		if (state == IBV_QPS_ERR) {
3094 			spdk_nvmf_rdma_start_disconnect(rqpair);
3095 		}
3096 		break;
3097 	case IBV_EVENT_QP_REQ_ERR:
3098 	case IBV_EVENT_QP_ACCESS_ERR:
3099 	case IBV_EVENT_COMM_EST:
3100 	case IBV_EVENT_PATH_MIG:
3101 	case IBV_EVENT_PATH_MIG_ERR:
3102 		SPDK_NOTICELOG("Async event: %s\n",
3103 			       ibv_event_type_str(event.event_type));
3104 		rqpair = event.element.qp->qp_context;
3105 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3106 				  (uintptr_t)rqpair->cm_id, event.event_type);
3107 		spdk_nvmf_rdma_update_ibv_state(rqpair);
3108 		break;
3109 	case IBV_EVENT_CQ_ERR:
3110 	case IBV_EVENT_DEVICE_FATAL:
3111 	case IBV_EVENT_PORT_ACTIVE:
3112 	case IBV_EVENT_PORT_ERR:
3113 	case IBV_EVENT_LID_CHANGE:
3114 	case IBV_EVENT_PKEY_CHANGE:
3115 	case IBV_EVENT_SM_CHANGE:
3116 	case IBV_EVENT_SRQ_ERR:
3117 	case IBV_EVENT_SRQ_LIMIT_REACHED:
3118 	case IBV_EVENT_CLIENT_REREGISTER:
3119 	case IBV_EVENT_GID_CHANGE:
3120 	default:
3121 		SPDK_NOTICELOG("Async event: %s\n",
3122 			       ibv_event_type_str(event.event_type));
3123 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
3124 		break;
3125 	}
3126 	ibv_ack_async_event(&event);
3127 }
3128 
3129 static void
3130 spdk_nvmf_rdma_accept(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
3131 {
3132 	int	nfds, i = 0;
3133 	struct spdk_nvmf_rdma_transport *rtransport;
3134 	struct spdk_nvmf_rdma_device *device, *tmp;
3135 
3136 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3137 	nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
3138 
3139 	if (nfds <= 0) {
3140 		return;
3141 	}
3142 
3143 	/* The first poll descriptor is RDMA CM event */
3144 	if (rtransport->poll_fds[i++].revents & POLLIN) {
3145 		spdk_nvmf_process_cm_event(transport, cb_fn);
3146 		nfds--;
3147 	}
3148 
3149 	if (nfds == 0) {
3150 		return;
3151 	}
3152 
3153 	/* Second and subsequent poll descriptors are IB async events */
3154 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
3155 		if (rtransport->poll_fds[i++].revents & POLLIN) {
3156 			spdk_nvmf_process_ib_event(device);
3157 			nfds--;
3158 		}
3159 	}
3160 	/* check all flagged fd's have been served */
3161 	assert(nfds == 0);
3162 }
3163 
3164 static void
3165 spdk_nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
3166 			struct spdk_nvme_transport_id *trid,
3167 			struct spdk_nvmf_discovery_log_page_entry *entry)
3168 {
3169 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
3170 	entry->adrfam = trid->adrfam;
3171 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
3172 
3173 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
3174 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
3175 
3176 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
3177 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
3178 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
3179 }
3180 
3181 static void
3182 spdk_nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
3183 
3184 static struct spdk_nvmf_transport_poll_group *
3185 spdk_nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
3186 {
3187 	struct spdk_nvmf_rdma_transport		*rtransport;
3188 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3189 	struct spdk_nvmf_rdma_poller		*poller;
3190 	struct spdk_nvmf_rdma_device		*device;
3191 	struct ibv_srq_init_attr		srq_init_attr;
3192 	struct spdk_nvmf_rdma_resource_opts	opts;
3193 	int					num_cqe;
3194 
3195 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3196 
3197 	rgroup = calloc(1, sizeof(*rgroup));
3198 	if (!rgroup) {
3199 		return NULL;
3200 	}
3201 
3202 	TAILQ_INIT(&rgroup->pollers);
3203 	STAILQ_INIT(&rgroup->retired_bufs);
3204 
3205 	pthread_mutex_lock(&rtransport->lock);
3206 	TAILQ_FOREACH(device, &rtransport->devices, link) {
3207 		poller = calloc(1, sizeof(*poller));
3208 		if (!poller) {
3209 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
3210 			spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
3211 			pthread_mutex_unlock(&rtransport->lock);
3212 			return NULL;
3213 		}
3214 
3215 		poller->device = device;
3216 		poller->group = rgroup;
3217 
3218 		TAILQ_INIT(&poller->qpairs);
3219 		STAILQ_INIT(&poller->qpairs_pending_send);
3220 		STAILQ_INIT(&poller->qpairs_pending_recv);
3221 
3222 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
3223 		if (transport->opts.no_srq == false && device->num_srq < device->attr.max_srq) {
3224 			poller->max_srq_depth = transport->opts.max_srq_depth;
3225 
3226 			device->num_srq++;
3227 			memset(&srq_init_attr, 0, sizeof(struct ibv_srq_init_attr));
3228 			srq_init_attr.attr.max_wr = poller->max_srq_depth;
3229 			srq_init_attr.attr.max_sge = spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
3230 			poller->srq = ibv_create_srq(device->pd, &srq_init_attr);
3231 			if (!poller->srq) {
3232 				SPDK_ERRLOG("Unable to create shared receive queue, errno %d\n", errno);
3233 				spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
3234 				pthread_mutex_unlock(&rtransport->lock);
3235 				return NULL;
3236 			}
3237 
3238 			opts.qp = poller->srq;
3239 			opts.pd = device->pd;
3240 			opts.qpair = NULL;
3241 			opts.shared = true;
3242 			opts.max_queue_depth = poller->max_srq_depth;
3243 			opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
3244 
3245 			poller->resources = nvmf_rdma_resources_create(&opts);
3246 			if (!poller->resources) {
3247 				SPDK_ERRLOG("Unable to allocate resources for shared receive queue.\n");
3248 				spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
3249 				pthread_mutex_unlock(&rtransport->lock);
3250 				return NULL;
3251 			}
3252 		}
3253 
3254 		/*
3255 		 * When using an srq, we can limit the completion queue at startup.
3256 		 * The following formula represents the calculation:
3257 		 * num_cqe = num_recv + num_data_wr + num_send_wr.
3258 		 * where num_recv=num_data_wr=and num_send_wr=poller->max_srq_depth
3259 		 */
3260 		if (poller->srq) {
3261 			num_cqe = poller->max_srq_depth * 3;
3262 		} else {
3263 			num_cqe = DEFAULT_NVMF_RDMA_CQ_SIZE;
3264 		}
3265 
3266 		poller->cq = ibv_create_cq(device->context, num_cqe, poller, NULL, 0);
3267 		if (!poller->cq) {
3268 			SPDK_ERRLOG("Unable to create completion queue\n");
3269 			spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
3270 			pthread_mutex_unlock(&rtransport->lock);
3271 			return NULL;
3272 		}
3273 		poller->num_cqe = num_cqe;
3274 	}
3275 
3276 	TAILQ_INSERT_TAIL(&rtransport->poll_groups, rgroup, link);
3277 	if (rtransport->conn_sched.next_admin_pg == NULL) {
3278 		rtransport->conn_sched.next_admin_pg = rgroup;
3279 		rtransport->conn_sched.next_io_pg = rgroup;
3280 	}
3281 
3282 	pthread_mutex_unlock(&rtransport->lock);
3283 	return &rgroup->group;
3284 }
3285 
3286 static struct spdk_nvmf_transport_poll_group *
3287 spdk_nvmf_rdma_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
3288 {
3289 	struct spdk_nvmf_rdma_transport *rtransport;
3290 	struct spdk_nvmf_rdma_poll_group **pg;
3291 	struct spdk_nvmf_transport_poll_group *result;
3292 
3293 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
3294 
3295 	pthread_mutex_lock(&rtransport->lock);
3296 
3297 	if (TAILQ_EMPTY(&rtransport->poll_groups)) {
3298 		pthread_mutex_unlock(&rtransport->lock);
3299 		return NULL;
3300 	}
3301 
3302 	if (qpair->qid == 0) {
3303 		pg = &rtransport->conn_sched.next_admin_pg;
3304 	} else {
3305 		pg = &rtransport->conn_sched.next_io_pg;
3306 	}
3307 
3308 	assert(*pg != NULL);
3309 
3310 	result = &(*pg)->group;
3311 
3312 	*pg = TAILQ_NEXT(*pg, link);
3313 	if (*pg == NULL) {
3314 		*pg = TAILQ_FIRST(&rtransport->poll_groups);
3315 	}
3316 
3317 	pthread_mutex_unlock(&rtransport->lock);
3318 
3319 	return result;
3320 }
3321 
3322 static void
3323 spdk_nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
3324 {
3325 	struct spdk_nvmf_rdma_poll_group	*rgroup, *next_rgroup;
3326 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
3327 	struct spdk_nvmf_rdma_qpair		*qpair, *tmp_qpair;
3328 	struct spdk_nvmf_transport_pg_cache_buf	*buf, *tmp_buf;
3329 	struct spdk_nvmf_rdma_transport		*rtransport;
3330 
3331 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3332 	rtransport = SPDK_CONTAINEROF(rgroup->group.transport, struct spdk_nvmf_rdma_transport, transport);
3333 
3334 	if (!rgroup) {
3335 		return;
3336 	}
3337 
3338 	/* free all retired buffers back to the transport so we don't short the mempool. */
3339 	STAILQ_FOREACH_SAFE(buf, &rgroup->retired_bufs, link, tmp_buf) {
3340 		STAILQ_REMOVE(&rgroup->retired_bufs, buf, spdk_nvmf_transport_pg_cache_buf, link);
3341 		assert(group->transport != NULL);
3342 		spdk_mempool_put(group->transport->data_buf_pool, buf);
3343 	}
3344 
3345 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
3346 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
3347 
3348 		TAILQ_FOREACH_SAFE(qpair, &poller->qpairs, link, tmp_qpair) {
3349 			spdk_nvmf_rdma_qpair_destroy(qpair);
3350 		}
3351 
3352 		if (poller->srq) {
3353 			nvmf_rdma_resources_destroy(poller->resources);
3354 			ibv_destroy_srq(poller->srq);
3355 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Destroyed RDMA shared queue %p\n", poller->srq);
3356 		}
3357 
3358 		if (poller->cq) {
3359 			ibv_destroy_cq(poller->cq);
3360 		}
3361 
3362 		free(poller);
3363 	}
3364 
3365 	pthread_mutex_lock(&rtransport->lock);
3366 	next_rgroup = TAILQ_NEXT(rgroup, link);
3367 	TAILQ_REMOVE(&rtransport->poll_groups, rgroup, link);
3368 	if (next_rgroup == NULL) {
3369 		next_rgroup = TAILQ_FIRST(&rtransport->poll_groups);
3370 	}
3371 	if (rtransport->conn_sched.next_admin_pg == rgroup) {
3372 		rtransport->conn_sched.next_admin_pg = next_rgroup;
3373 	}
3374 	if (rtransport->conn_sched.next_io_pg == rgroup) {
3375 		rtransport->conn_sched.next_io_pg = next_rgroup;
3376 	}
3377 	pthread_mutex_unlock(&rtransport->lock);
3378 
3379 	free(rgroup);
3380 }
3381 
3382 static void
3383 spdk_nvmf_rdma_qpair_reject_connection(struct spdk_nvmf_rdma_qpair *rqpair)
3384 {
3385 	if (rqpair->cm_id != NULL) {
3386 		spdk_nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
3387 	}
3388 	spdk_nvmf_rdma_qpair_destroy(rqpair);
3389 }
3390 
3391 static int
3392 spdk_nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
3393 			      struct spdk_nvmf_qpair *qpair)
3394 {
3395 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3396 	struct spdk_nvmf_rdma_qpair		*rqpair;
3397 	struct spdk_nvmf_rdma_device		*device;
3398 	struct spdk_nvmf_rdma_poller		*poller;
3399 	int					rc;
3400 
3401 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3402 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3403 
3404 	device = rqpair->port->device;
3405 
3406 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
3407 		if (poller->device == device) {
3408 			break;
3409 		}
3410 	}
3411 
3412 	if (!poller) {
3413 		SPDK_ERRLOG("No poller found for device.\n");
3414 		return -1;
3415 	}
3416 
3417 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
3418 	rqpair->poller = poller;
3419 	rqpair->srq = rqpair->poller->srq;
3420 
3421 	rc = spdk_nvmf_rdma_qpair_initialize(qpair);
3422 	if (rc < 0) {
3423 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
3424 		return -1;
3425 	}
3426 
3427 	rc = spdk_nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
3428 	if (rc) {
3429 		/* Try to reject, but we probably can't */
3430 		spdk_nvmf_rdma_qpair_reject_connection(rqpair);
3431 		return -1;
3432 	}
3433 
3434 	spdk_nvmf_rdma_update_ibv_state(rqpair);
3435 
3436 	return 0;
3437 }
3438 
3439 static int
3440 spdk_nvmf_rdma_request_free(struct spdk_nvmf_request *req)
3441 {
3442 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
3443 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3444 			struct spdk_nvmf_rdma_transport, transport);
3445 
3446 	nvmf_rdma_request_free(rdma_req, rtransport);
3447 	return 0;
3448 }
3449 
3450 static int
3451 spdk_nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
3452 {
3453 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3454 			struct spdk_nvmf_rdma_transport, transport);
3455 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
3456 			struct spdk_nvmf_rdma_request, req);
3457 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3458 			struct spdk_nvmf_rdma_qpair, qpair);
3459 
3460 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3461 		/* The connection is alive, so process the request as normal */
3462 		rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
3463 	} else {
3464 		/* The connection is dead. Move the request directly to the completed state. */
3465 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3466 	}
3467 
3468 	spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3469 
3470 	return 0;
3471 }
3472 
3473 static int
3474 spdk_nvmf_rdma_destroy_defunct_qpair(void *ctx)
3475 {
3476 	struct spdk_nvmf_rdma_qpair	*rqpair = ctx;
3477 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
3478 			struct spdk_nvmf_rdma_transport, transport);
3479 
3480 	SPDK_INFOLOG(SPDK_LOG_RDMA, "QP#%d hasn't been drained as expected, manually destroy it\n",
3481 		     rqpair->qpair.qid);
3482 
3483 	spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
3484 	spdk_nvmf_rdma_qpair_destroy(rqpair);
3485 
3486 	return 0;
3487 }
3488 
3489 static void
3490 spdk_nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair)
3491 {
3492 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3493 
3494 	if (rqpair->disconnect_flags & RDMA_QP_DISCONNECTING) {
3495 		return;
3496 	}
3497 
3498 	rqpair->disconnect_flags |= RDMA_QP_DISCONNECTING;
3499 
3500 	/* This happens only when the qpair is disconnected before
3501 	 * it is added to the poll group. Since there is no poll group,
3502 	 * the RDMA qp has not been initialized yet and the RDMA CM
3503 	 * event has not yet been acknowledged, so we need to reject it.
3504 	 */
3505 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
3506 		spdk_nvmf_rdma_qpair_reject_connection(rqpair);
3507 		return;
3508 	}
3509 
3510 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3511 		spdk_nvmf_rdma_set_ibv_state(rqpair, IBV_QPS_ERR);
3512 	}
3513 
3514 	rqpair->destruct_poller = spdk_poller_register(spdk_nvmf_rdma_destroy_defunct_qpair, (void *)rqpair,
3515 				  NVMF_RDMA_QPAIR_DESTROY_TIMEOUT_US);
3516 }
3517 
3518 static struct spdk_nvmf_rdma_qpair *
3519 get_rdma_qpair_from_wc(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_wc *wc)
3520 {
3521 	struct spdk_nvmf_rdma_qpair *rqpair;
3522 	/* @todo: improve QP search */
3523 	TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
3524 		if (wc->qp_num == rqpair->cm_id->qp->qp_num) {
3525 			return rqpair;
3526 		}
3527 	}
3528 	SPDK_ERRLOG("Didn't find QP with qp_num %u\n", wc->qp_num);
3529 	return NULL;
3530 }
3531 
3532 #ifdef DEBUG
3533 static int
3534 spdk_nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
3535 {
3536 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
3537 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
3538 }
3539 #endif
3540 
3541 static void
3542 _poller_reset_failed_recvs(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_recv_wr *bad_recv_wr,
3543 			   int rc)
3544 {
3545 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3546 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3547 
3548 	SPDK_ERRLOG("Failed to post a recv for the poller %p with errno %d\n", rpoller, -rc);
3549 	while (bad_recv_wr != NULL) {
3550 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_recv_wr->wr_id;
3551 		rdma_recv = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3552 
3553 		rdma_recv->qpair->current_recv_depth++;
3554 		bad_recv_wr = bad_recv_wr->next;
3555 		SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rdma_recv->qpair, -rc);
3556 		spdk_nvmf_rdma_start_disconnect(rdma_recv->qpair);
3557 	}
3558 }
3559 
3560 static void
3561 _qp_reset_failed_recvs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *bad_recv_wr, int rc)
3562 {
3563 	SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rqpair, -rc);
3564 	while (bad_recv_wr != NULL) {
3565 		bad_recv_wr = bad_recv_wr->next;
3566 		rqpair->current_recv_depth++;
3567 	}
3568 	spdk_nvmf_rdma_start_disconnect(rqpair);
3569 }
3570 
3571 static void
3572 _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
3573 		     struct spdk_nvmf_rdma_poller *rpoller)
3574 {
3575 	struct spdk_nvmf_rdma_qpair	*rqpair;
3576 	struct ibv_recv_wr		*bad_recv_wr;
3577 	int				rc;
3578 
3579 	if (rpoller->srq) {
3580 		if (rpoller->resources->recvs_to_post.first != NULL) {
3581 			rc = ibv_post_srq_recv(rpoller->srq, rpoller->resources->recvs_to_post.first, &bad_recv_wr);
3582 			if (rc) {
3583 				_poller_reset_failed_recvs(rpoller, bad_recv_wr, rc);
3584 			}
3585 			rpoller->resources->recvs_to_post.first = NULL;
3586 			rpoller->resources->recvs_to_post.last = NULL;
3587 		}
3588 	} else {
3589 		while (!STAILQ_EMPTY(&rpoller->qpairs_pending_recv)) {
3590 			rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_recv);
3591 			assert(rqpair->resources->recvs_to_post.first != NULL);
3592 			rc = ibv_post_recv(rqpair->cm_id->qp, rqpair->resources->recvs_to_post.first, &bad_recv_wr);
3593 			if (rc) {
3594 				_qp_reset_failed_recvs(rqpair, bad_recv_wr, rc);
3595 			}
3596 			rqpair->resources->recvs_to_post.first = NULL;
3597 			rqpair->resources->recvs_to_post.last = NULL;
3598 			STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_recv, recv_link);
3599 		}
3600 	}
3601 }
3602 
3603 static void
3604 _qp_reset_failed_sends(struct spdk_nvmf_rdma_transport *rtransport,
3605 		       struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_send_wr *bad_wr, int rc)
3606 {
3607 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3608 	struct spdk_nvmf_rdma_request	*prev_rdma_req = NULL, *cur_rdma_req = NULL;
3609 
3610 	SPDK_ERRLOG("Failed to post a send for the qpair %p with errno %d\n", rqpair, -rc);
3611 	for (; bad_wr != NULL; bad_wr = bad_wr->next) {
3612 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_wr->wr_id;
3613 		assert(rqpair->current_send_depth > 0);
3614 		rqpair->current_send_depth--;
3615 		switch (bad_rdma_wr->type) {
3616 		case RDMA_WR_TYPE_DATA:
3617 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3618 			if (bad_wr->opcode == IBV_WR_RDMA_READ) {
3619 				assert(rqpair->current_read_depth > 0);
3620 				rqpair->current_read_depth--;
3621 			}
3622 			break;
3623 		case RDMA_WR_TYPE_SEND:
3624 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3625 			break;
3626 		default:
3627 			SPDK_ERRLOG("Found a RECV in the list of pending SEND requests for qpair %p\n", rqpair);
3628 			prev_rdma_req = cur_rdma_req;
3629 			continue;
3630 		}
3631 
3632 		if (prev_rdma_req == cur_rdma_req) {
3633 			/* this request was handled by an earlier wr. i.e. we were performing an nvme read. */
3634 			/* We only have to check against prev_wr since each requests wrs are contiguous in this list. */
3635 			continue;
3636 		}
3637 
3638 		switch (cur_rdma_req->state) {
3639 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
3640 			cur_rdma_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
3641 			cur_rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
3642 			break;
3643 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
3644 		case RDMA_REQUEST_STATE_COMPLETING:
3645 			cur_rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3646 			break;
3647 		default:
3648 			SPDK_ERRLOG("Found a request in a bad state %d when draining pending SEND requests for qpair %p\n",
3649 				    cur_rdma_req->state, rqpair);
3650 			continue;
3651 		}
3652 
3653 		spdk_nvmf_rdma_request_process(rtransport, cur_rdma_req);
3654 		prev_rdma_req = cur_rdma_req;
3655 	}
3656 
3657 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3658 		/* Disconnect the connection. */
3659 		spdk_nvmf_rdma_start_disconnect(rqpair);
3660 	}
3661 
3662 }
3663 
3664 static void
3665 _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
3666 		     struct spdk_nvmf_rdma_poller *rpoller)
3667 {
3668 	struct spdk_nvmf_rdma_qpair	*rqpair;
3669 	struct ibv_send_wr		*bad_wr = NULL;
3670 	int				rc;
3671 
3672 	while (!STAILQ_EMPTY(&rpoller->qpairs_pending_send)) {
3673 		rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_send);
3674 		assert(rqpair->sends_to_post.first != NULL);
3675 		rc = ibv_post_send(rqpair->cm_id->qp, rqpair->sends_to_post.first, &bad_wr);
3676 
3677 		/* bad wr always points to the first wr that failed. */
3678 		if (rc) {
3679 			_qp_reset_failed_sends(rtransport, rqpair, bad_wr, rc);
3680 		}
3681 		rqpair->sends_to_post.first = NULL;
3682 		rqpair->sends_to_post.last = NULL;
3683 		STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_send, send_link);
3684 	}
3685 }
3686 
3687 static int
3688 spdk_nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
3689 			   struct spdk_nvmf_rdma_poller *rpoller)
3690 {
3691 	struct ibv_wc wc[32];
3692 	struct spdk_nvmf_rdma_wr	*rdma_wr;
3693 	struct spdk_nvmf_rdma_request	*rdma_req;
3694 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3695 	struct spdk_nvmf_rdma_qpair	*rqpair;
3696 	int reaped, i;
3697 	int count = 0;
3698 	bool error = false;
3699 	uint64_t poll_tsc = spdk_get_ticks();
3700 
3701 	/* Poll for completing operations. */
3702 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
3703 	if (reaped < 0) {
3704 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
3705 			    errno, spdk_strerror(errno));
3706 		return -1;
3707 	}
3708 
3709 	rpoller->stat.polls++;
3710 	rpoller->stat.completions += reaped;
3711 
3712 	for (i = 0; i < reaped; i++) {
3713 
3714 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
3715 
3716 		switch (rdma_wr->type) {
3717 		case RDMA_WR_TYPE_SEND:
3718 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3719 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3720 
3721 			if (!wc[i].status) {
3722 				count++;
3723 				assert(wc[i].opcode == IBV_WC_SEND);
3724 				assert(spdk_nvmf_rdma_req_is_completing(rdma_req));
3725 			} else {
3726 				SPDK_ERRLOG("data=%p length=%u\n", rdma_req->req.data, rdma_req->req.length);
3727 			}
3728 
3729 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3730 			/* +1 for the response wr */
3731 			rqpair->current_send_depth -= rdma_req->num_outstanding_data_wr + 1;
3732 			rdma_req->num_outstanding_data_wr = 0;
3733 
3734 			spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3735 			break;
3736 		case RDMA_WR_TYPE_RECV:
3737 			/* rdma_recv->qpair will be invalid if using an SRQ.  In that case we have to get the qpair from the wc. */
3738 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3739 			if (rpoller->srq != NULL) {
3740 				rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
3741 				/* It is possible that there are still some completions for destroyed QP
3742 				 * associated with SRQ. We just ignore these late completions and re-post
3743 				 * receive WRs back to SRQ.
3744 				 */
3745 				if (spdk_unlikely(NULL == rdma_recv->qpair)) {
3746 					struct ibv_recv_wr *bad_wr;
3747 					int rc;
3748 
3749 					rdma_recv->wr.next = NULL;
3750 					rc = ibv_post_srq_recv(rpoller->srq,
3751 							       &rdma_recv->wr,
3752 							       &bad_wr);
3753 					if (rc) {
3754 						SPDK_ERRLOG("Failed to re-post recv WR to SRQ, err %d\n", rc);
3755 					}
3756 					continue;
3757 				}
3758 			}
3759 			rqpair = rdma_recv->qpair;
3760 
3761 			assert(rqpair != NULL);
3762 			if (!wc[i].status) {
3763 				assert(wc[i].opcode == IBV_WC_RECV);
3764 				if (rqpair->current_recv_depth >= rqpair->max_queue_depth) {
3765 					spdk_nvmf_rdma_start_disconnect(rqpair);
3766 					break;
3767 				}
3768 			}
3769 
3770 			rdma_recv->wr.next = NULL;
3771 			rqpair->current_recv_depth++;
3772 			rdma_recv->receive_tsc = poll_tsc;
3773 			rpoller->stat.requests++;
3774 			STAILQ_INSERT_TAIL(&rqpair->resources->incoming_queue, rdma_recv, link);
3775 			break;
3776 		case RDMA_WR_TYPE_DATA:
3777 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3778 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3779 
3780 			assert(rdma_req->num_outstanding_data_wr > 0);
3781 
3782 			rqpair->current_send_depth--;
3783 			rdma_req->num_outstanding_data_wr--;
3784 			if (!wc[i].status) {
3785 				assert(wc[i].opcode == IBV_WC_RDMA_READ);
3786 				rqpair->current_read_depth--;
3787 				/* wait for all outstanding reads associated with the same rdma_req to complete before proceeding. */
3788 				if (rdma_req->num_outstanding_data_wr == 0) {
3789 					rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
3790 					spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3791 				}
3792 			} else {
3793 				/* If the data transfer fails still force the queue into the error state,
3794 				 * if we were performing an RDMA_READ, we need to force the request into a
3795 				 * completed state since it wasn't linked to a send. However, in the RDMA_WRITE
3796 				 * case, we should wait for the SEND to complete. */
3797 				SPDK_ERRLOG("data=%p length=%u\n", rdma_req->req.data, rdma_req->req.length);
3798 				if (rdma_req->data.wr.opcode == IBV_WR_RDMA_READ) {
3799 					rqpair->current_read_depth--;
3800 					if (rdma_req->num_outstanding_data_wr == 0) {
3801 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3802 					}
3803 				}
3804 			}
3805 			break;
3806 		default:
3807 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
3808 			continue;
3809 		}
3810 
3811 		/* Handle error conditions */
3812 		if (wc[i].status) {
3813 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "CQ error on CQ %p, Request 0x%lu (%d): %s\n",
3814 				      rpoller->cq, wc[i].wr_id, wc[i].status, ibv_wc_status_str(wc[i].status));
3815 
3816 			error = true;
3817 
3818 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3819 				/* Disconnect the connection. */
3820 				spdk_nvmf_rdma_start_disconnect(rqpair);
3821 			} else {
3822 				nvmf_rdma_destroy_drained_qpair(rqpair);
3823 			}
3824 			continue;
3825 		}
3826 
3827 		spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3828 
3829 		if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
3830 			nvmf_rdma_destroy_drained_qpair(rqpair);
3831 		}
3832 	}
3833 
3834 	if (error == true) {
3835 		return -1;
3836 	}
3837 
3838 	/* submit outstanding work requests. */
3839 	_poller_submit_recvs(rtransport, rpoller);
3840 	_poller_submit_sends(rtransport, rpoller);
3841 
3842 	return count;
3843 }
3844 
3845 static int
3846 spdk_nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3847 {
3848 	struct spdk_nvmf_rdma_transport *rtransport;
3849 	struct spdk_nvmf_rdma_poll_group *rgroup;
3850 	struct spdk_nvmf_rdma_poller	*rpoller;
3851 	int				count, rc;
3852 
3853 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
3854 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3855 
3856 	count = 0;
3857 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3858 		rc = spdk_nvmf_rdma_poller_poll(rtransport, rpoller);
3859 		if (rc < 0) {
3860 			return rc;
3861 		}
3862 		count += rc;
3863 	}
3864 
3865 	return count;
3866 }
3867 
3868 static int
3869 spdk_nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
3870 			       struct spdk_nvme_transport_id *trid,
3871 			       bool peer)
3872 {
3873 	struct sockaddr *saddr;
3874 	uint16_t port;
3875 
3876 	trid->trtype = SPDK_NVME_TRANSPORT_RDMA;
3877 
3878 	if (peer) {
3879 		saddr = rdma_get_peer_addr(id);
3880 	} else {
3881 		saddr = rdma_get_local_addr(id);
3882 	}
3883 	switch (saddr->sa_family) {
3884 	case AF_INET: {
3885 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
3886 
3887 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3888 		inet_ntop(AF_INET, &saddr_in->sin_addr,
3889 			  trid->traddr, sizeof(trid->traddr));
3890 		if (peer) {
3891 			port = ntohs(rdma_get_dst_port(id));
3892 		} else {
3893 			port = ntohs(rdma_get_src_port(id));
3894 		}
3895 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3896 		break;
3897 	}
3898 	case AF_INET6: {
3899 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
3900 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3901 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
3902 			  trid->traddr, sizeof(trid->traddr));
3903 		if (peer) {
3904 			port = ntohs(rdma_get_dst_port(id));
3905 		} else {
3906 			port = ntohs(rdma_get_src_port(id));
3907 		}
3908 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3909 		break;
3910 	}
3911 	default:
3912 		return -1;
3913 
3914 	}
3915 
3916 	return 0;
3917 }
3918 
3919 static int
3920 spdk_nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
3921 				   struct spdk_nvme_transport_id *trid)
3922 {
3923 	struct spdk_nvmf_rdma_qpair	*rqpair;
3924 
3925 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3926 
3927 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
3928 }
3929 
3930 static int
3931 spdk_nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
3932 				    struct spdk_nvme_transport_id *trid)
3933 {
3934 	struct spdk_nvmf_rdma_qpair	*rqpair;
3935 
3936 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3937 
3938 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
3939 }
3940 
3941 static int
3942 spdk_nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
3943 				     struct spdk_nvme_transport_id *trid)
3944 {
3945 	struct spdk_nvmf_rdma_qpair	*rqpair;
3946 
3947 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3948 
3949 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
3950 }
3951 
3952 void
3953 spdk_nvmf_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
3954 {
3955 	g_nvmf_hooks = *hooks;
3956 }
3957 
3958 static int
3959 spdk_nvmf_rdma_poll_group_get_stat(struct spdk_nvmf_tgt *tgt,
3960 				   struct spdk_nvmf_transport_poll_group_stat **stat)
3961 {
3962 	struct spdk_io_channel *ch;
3963 	struct spdk_nvmf_poll_group *group;
3964 	struct spdk_nvmf_transport_poll_group *tgroup;
3965 	struct spdk_nvmf_rdma_poll_group *rgroup;
3966 	struct spdk_nvmf_rdma_poller *rpoller;
3967 	struct spdk_nvmf_rdma_device_stat *device_stat;
3968 	uint64_t num_devices = 0;
3969 
3970 	if (tgt == NULL || stat == NULL) {
3971 		return -EINVAL;
3972 	}
3973 
3974 	ch = spdk_get_io_channel(tgt);
3975 	group = spdk_io_channel_get_ctx(ch);;
3976 	spdk_put_io_channel(ch);
3977 	TAILQ_FOREACH(tgroup, &group->tgroups, link) {
3978 		if (SPDK_NVME_TRANSPORT_RDMA == tgroup->transport->ops->type) {
3979 			*stat = calloc(1, sizeof(struct spdk_nvmf_transport_poll_group_stat));
3980 			if (!*stat) {
3981 				SPDK_ERRLOG("Failed to allocate memory for NVMf RDMA statistics\n");
3982 				return -ENOMEM;
3983 			}
3984 			(*stat)->trtype = SPDK_NVME_TRANSPORT_RDMA;
3985 
3986 			rgroup = SPDK_CONTAINEROF(tgroup, struct spdk_nvmf_rdma_poll_group, group);
3987 			/* Count devices to allocate enough memory */
3988 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3989 				++num_devices;
3990 			}
3991 			(*stat)->rdma.devices = calloc(num_devices, sizeof(struct spdk_nvmf_rdma_device_stat));
3992 			if (!(*stat)->rdma.devices) {
3993 				SPDK_ERRLOG("Failed to allocate NVMf RDMA devices statistics\n");
3994 				free(*stat);
3995 				return -ENOMEM;
3996 			}
3997 
3998 			(*stat)->rdma.pending_data_buffer = rgroup->stat.pending_data_buffer;
3999 			(*stat)->rdma.num_devices = num_devices;
4000 			num_devices = 0;
4001 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4002 				device_stat = &(*stat)->rdma.devices[num_devices++];
4003 				device_stat->name = ibv_get_device_name(rpoller->device->context->device);
4004 				device_stat->polls = rpoller->stat.polls;
4005 				device_stat->completions = rpoller->stat.completions;
4006 				device_stat->requests = rpoller->stat.requests;
4007 				device_stat->request_latency = rpoller->stat.request_latency;
4008 				device_stat->pending_free_request = rpoller->stat.pending_free_request;
4009 				device_stat->pending_rdma_read = rpoller->stat.pending_rdma_read;
4010 				device_stat->pending_rdma_write = rpoller->stat.pending_rdma_write;
4011 			}
4012 			return 0;
4013 		}
4014 	}
4015 	return -ENOENT;
4016 }
4017 
4018 static void
4019 spdk_nvmf_rdma_poll_group_free_stat(struct spdk_nvmf_transport_poll_group_stat *stat)
4020 {
4021 	if (stat) {
4022 		free(stat->rdma.devices);
4023 	}
4024 	free(stat);
4025 }
4026 
4027 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
4028 	.type = SPDK_NVME_TRANSPORT_RDMA,
4029 	.opts_init = spdk_nvmf_rdma_opts_init,
4030 	.create = spdk_nvmf_rdma_create,
4031 	.destroy = spdk_nvmf_rdma_destroy,
4032 
4033 	.listen = spdk_nvmf_rdma_listen,
4034 	.stop_listen = spdk_nvmf_rdma_stop_listen,
4035 	.accept = spdk_nvmf_rdma_accept,
4036 
4037 	.listener_discover = spdk_nvmf_rdma_discover,
4038 
4039 	.poll_group_create = spdk_nvmf_rdma_poll_group_create,
4040 	.get_optimal_poll_group = spdk_nvmf_rdma_get_optimal_poll_group,
4041 	.poll_group_destroy = spdk_nvmf_rdma_poll_group_destroy,
4042 	.poll_group_add = spdk_nvmf_rdma_poll_group_add,
4043 	.poll_group_poll = spdk_nvmf_rdma_poll_group_poll,
4044 
4045 	.req_free = spdk_nvmf_rdma_request_free,
4046 	.req_complete = spdk_nvmf_rdma_request_complete,
4047 
4048 	.qpair_fini = spdk_nvmf_rdma_close_qpair,
4049 	.qpair_get_peer_trid = spdk_nvmf_rdma_qpair_get_peer_trid,
4050 	.qpair_get_local_trid = spdk_nvmf_rdma_qpair_get_local_trid,
4051 	.qpair_get_listen_trid = spdk_nvmf_rdma_qpair_get_listen_trid,
4052 
4053 	.poll_group_get_stat = spdk_nvmf_rdma_poll_group_get_stat,
4054 	.poll_group_free_stat = spdk_nvmf_rdma_poll_group_free_stat,
4055 };
4056 
4057 SPDK_LOG_REGISTER_COMPONENT("rdma", SPDK_LOG_RDMA)
4058