xref: /spdk/lib/nvmf/rdma.c (revision cf3ed0e19f8621f03136d6ec1fbd9417519bbe6a)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2019-2021 Mellanox Technologies LTD. All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "spdk/stdinc.h"
35 
36 #include "spdk/config.h"
37 #include "spdk/thread.h"
38 #include "spdk/likely.h"
39 #include "spdk/nvmf_transport.h"
40 #include "spdk/string.h"
41 #include "spdk/trace.h"
42 #include "spdk/util.h"
43 
44 #include "spdk_internal/assert.h"
45 #include "spdk/log.h"
46 #include "spdk_internal/rdma.h"
47 
48 #include "nvmf_internal.h"
49 
50 struct spdk_nvme_rdma_hooks g_nvmf_hooks = {};
51 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma;
52 
53 /*
54  RDMA Connection Resource Defaults
55  */
56 #define NVMF_DEFAULT_TX_SGE		SPDK_NVMF_MAX_SGL_ENTRIES
57 #define NVMF_DEFAULT_RSP_SGE		1
58 #define NVMF_DEFAULT_RX_SGE		2
59 
60 /* The RDMA completion queue size */
61 #define DEFAULT_NVMF_RDMA_CQ_SIZE	4096
62 #define MAX_WR_PER_QP(queue_depth)	(queue_depth * 3 + 2)
63 
64 /* rxe driver vendor_id has been changed from 0 to 0XFFFFFF in 0184afd15a141d7ce24c32c0d86a1e3ba6bc0eb3 */
65 #define NVMF_RXE_VENDOR_ID_OLD 0
66 #define NVMF_RXE_VENDOR_ID_NEW 0XFFFFFF
67 
68 static int g_spdk_nvmf_ibv_query_mask =
69 	IBV_QP_STATE |
70 	IBV_QP_PKEY_INDEX |
71 	IBV_QP_PORT |
72 	IBV_QP_ACCESS_FLAGS |
73 	IBV_QP_AV |
74 	IBV_QP_PATH_MTU |
75 	IBV_QP_DEST_QPN |
76 	IBV_QP_RQ_PSN |
77 	IBV_QP_MAX_DEST_RD_ATOMIC |
78 	IBV_QP_MIN_RNR_TIMER |
79 	IBV_QP_SQ_PSN |
80 	IBV_QP_TIMEOUT |
81 	IBV_QP_RETRY_CNT |
82 	IBV_QP_RNR_RETRY |
83 	IBV_QP_MAX_QP_RD_ATOMIC;
84 
85 enum spdk_nvmf_rdma_request_state {
86 	/* The request is not currently in use */
87 	RDMA_REQUEST_STATE_FREE = 0,
88 
89 	/* Initial state when request first received */
90 	RDMA_REQUEST_STATE_NEW,
91 
92 	/* The request is queued until a data buffer is available. */
93 	RDMA_REQUEST_STATE_NEED_BUFFER,
94 
95 	/* The request is waiting on RDMA queue depth availability
96 	 * to transfer data from the host to the controller.
97 	 */
98 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
99 
100 	/* The request is currently transferring data from the host to the controller. */
101 	RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
102 
103 	/* The request is ready to execute at the block device */
104 	RDMA_REQUEST_STATE_READY_TO_EXECUTE,
105 
106 	/* The request is currently executing at the block device */
107 	RDMA_REQUEST_STATE_EXECUTING,
108 
109 	/* The request finished executing at the block device */
110 	RDMA_REQUEST_STATE_EXECUTED,
111 
112 	/* The request is waiting on RDMA queue depth availability
113 	 * to transfer data from the controller to the host.
114 	 */
115 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
116 
117 	/* The request is ready to send a completion */
118 	RDMA_REQUEST_STATE_READY_TO_COMPLETE,
119 
120 	/* The request is currently transferring data from the controller to the host. */
121 	RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
122 
123 	/* The request currently has an outstanding completion without an
124 	 * associated data transfer.
125 	 */
126 	RDMA_REQUEST_STATE_COMPLETING,
127 
128 	/* The request completed and can be marked free. */
129 	RDMA_REQUEST_STATE_COMPLETED,
130 
131 	/* Terminator */
132 	RDMA_REQUEST_NUM_STATES,
133 };
134 
135 #define OBJECT_NVMF_RDMA_IO				0x40
136 
137 #define TRACE_GROUP_NVMF_RDMA				0x4
138 #define TRACE_RDMA_REQUEST_STATE_NEW					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x0)
139 #define TRACE_RDMA_REQUEST_STATE_NEED_BUFFER				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x1)
140 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x2)
141 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x3)
142 #define TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x4)
143 #define TRACE_RDMA_REQUEST_STATE_EXECUTING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x5)
144 #define TRACE_RDMA_REQUEST_STATE_EXECUTED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x6)
145 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING		SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x7)
146 #define TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x8)
147 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x9)
148 #define TRACE_RDMA_REQUEST_STATE_COMPLETING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xA)
149 #define TRACE_RDMA_REQUEST_STATE_COMPLETED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xB)
150 #define TRACE_RDMA_QP_CREATE						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xC)
151 #define TRACE_RDMA_IBV_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xD)
152 #define TRACE_RDMA_CM_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xE)
153 #define TRACE_RDMA_QP_STATE_CHANGE					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xF)
154 #define TRACE_RDMA_QP_DISCONNECT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x10)
155 #define TRACE_RDMA_QP_DESTROY						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x11)
156 
157 SPDK_TRACE_REGISTER_FN(nvmf_trace, "nvmf_rdma", TRACE_GROUP_NVMF_RDMA)
158 {
159 	spdk_trace_register_object(OBJECT_NVMF_RDMA_IO, 'r');
160 	spdk_trace_register_description("RDMA_REQ_NEW", TRACE_RDMA_REQUEST_STATE_NEW,
161 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 1, 1, "cmid:   ");
162 	spdk_trace_register_description("RDMA_REQ_NEED_BUFFER", TRACE_RDMA_REQUEST_STATE_NEED_BUFFER,
163 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
164 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_C2H",
165 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
166 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
167 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_H2C",
168 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
169 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
170 	spdk_trace_register_description("RDMA_REQ_TX_H2C",
171 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
172 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
173 	spdk_trace_register_description("RDMA_REQ_RDY_TO_EXECUTE",
174 					TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE,
175 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
176 	spdk_trace_register_description("RDMA_REQ_EXECUTING",
177 					TRACE_RDMA_REQUEST_STATE_EXECUTING,
178 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
179 	spdk_trace_register_description("RDMA_REQ_EXECUTED",
180 					TRACE_RDMA_REQUEST_STATE_EXECUTED,
181 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
182 	spdk_trace_register_description("RDMA_REQ_RDY_TO_COMPL",
183 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE,
184 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
185 	spdk_trace_register_description("RDMA_REQ_COMPLETING_C2H",
186 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
187 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
188 	spdk_trace_register_description("RDMA_REQ_COMPLETING",
189 					TRACE_RDMA_REQUEST_STATE_COMPLETING,
190 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
191 	spdk_trace_register_description("RDMA_REQ_COMPLETED",
192 					TRACE_RDMA_REQUEST_STATE_COMPLETED,
193 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
194 
195 	spdk_trace_register_description("RDMA_QP_CREATE", TRACE_RDMA_QP_CREATE,
196 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
197 	spdk_trace_register_description("RDMA_IBV_ASYNC_EVENT", TRACE_RDMA_IBV_ASYNC_EVENT,
198 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
199 	spdk_trace_register_description("RDMA_CM_ASYNC_EVENT", TRACE_RDMA_CM_ASYNC_EVENT,
200 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
201 	spdk_trace_register_description("RDMA_QP_STATE_CHANGE", TRACE_RDMA_QP_STATE_CHANGE,
202 					OWNER_NONE, OBJECT_NONE, 0, 1, "state:  ");
203 	spdk_trace_register_description("RDMA_QP_DISCONNECT", TRACE_RDMA_QP_DISCONNECT,
204 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
205 	spdk_trace_register_description("RDMA_QP_DESTROY", TRACE_RDMA_QP_DESTROY,
206 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
207 }
208 
209 enum spdk_nvmf_rdma_wr_type {
210 	RDMA_WR_TYPE_RECV,
211 	RDMA_WR_TYPE_SEND,
212 	RDMA_WR_TYPE_DATA,
213 };
214 
215 struct spdk_nvmf_rdma_wr {
216 	enum spdk_nvmf_rdma_wr_type	type;
217 };
218 
219 /* This structure holds commands as they are received off the wire.
220  * It must be dynamically paired with a full request object
221  * (spdk_nvmf_rdma_request) to service a request. It is separate
222  * from the request because RDMA does not appear to order
223  * completions, so occasionally we'll get a new incoming
224  * command when there aren't any free request objects.
225  */
226 struct spdk_nvmf_rdma_recv {
227 	struct ibv_recv_wr			wr;
228 	struct ibv_sge				sgl[NVMF_DEFAULT_RX_SGE];
229 
230 	struct spdk_nvmf_rdma_qpair		*qpair;
231 
232 	/* In-capsule data buffer */
233 	uint8_t					*buf;
234 
235 	struct spdk_nvmf_rdma_wr		rdma_wr;
236 	uint64_t				receive_tsc;
237 
238 	STAILQ_ENTRY(spdk_nvmf_rdma_recv)	link;
239 };
240 
241 struct spdk_nvmf_rdma_request_data {
242 	struct spdk_nvmf_rdma_wr	rdma_wr;
243 	struct ibv_send_wr		wr;
244 	struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
245 };
246 
247 struct spdk_nvmf_rdma_request {
248 	struct spdk_nvmf_request		req;
249 
250 	enum spdk_nvmf_rdma_request_state	state;
251 
252 	struct spdk_nvmf_rdma_recv		*recv;
253 
254 	struct {
255 		struct spdk_nvmf_rdma_wr	rdma_wr;
256 		struct	ibv_send_wr		wr;
257 		struct	ibv_sge			sgl[NVMF_DEFAULT_RSP_SGE];
258 	} rsp;
259 
260 	struct spdk_nvmf_rdma_request_data	data;
261 
262 	uint32_t				iovpos;
263 
264 	uint32_t				num_outstanding_data_wr;
265 	uint64_t				receive_tsc;
266 
267 	STAILQ_ENTRY(spdk_nvmf_rdma_request)	state_link;
268 };
269 
270 struct spdk_nvmf_rdma_resource_opts {
271 	struct spdk_nvmf_rdma_qpair	*qpair;
272 	/* qp points either to an ibv_qp object or an ibv_srq object depending on the value of shared. */
273 	void				*qp;
274 	struct ibv_pd			*pd;
275 	uint32_t			max_queue_depth;
276 	uint32_t			in_capsule_data_size;
277 	bool				shared;
278 };
279 
280 struct spdk_nvmf_recv_wr_list {
281 	struct ibv_recv_wr	*first;
282 	struct ibv_recv_wr	*last;
283 };
284 
285 struct spdk_nvmf_rdma_resources {
286 	/* Array of size "max_queue_depth" containing RDMA requests. */
287 	struct spdk_nvmf_rdma_request		*reqs;
288 
289 	/* Array of size "max_queue_depth" containing RDMA recvs. */
290 	struct spdk_nvmf_rdma_recv		*recvs;
291 
292 	/* Array of size "max_queue_depth" containing 64 byte capsules
293 	 * used for receive.
294 	 */
295 	union nvmf_h2c_msg			*cmds;
296 	struct ibv_mr				*cmds_mr;
297 
298 	/* Array of size "max_queue_depth" containing 16 byte completions
299 	 * to be sent back to the user.
300 	 */
301 	union nvmf_c2h_msg			*cpls;
302 	struct ibv_mr				*cpls_mr;
303 
304 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
305 	 * buffers to be used for in capsule data.
306 	 */
307 	void					*bufs;
308 	struct ibv_mr				*bufs_mr;
309 
310 	/* The list of pending recvs to transfer */
311 	struct spdk_nvmf_recv_wr_list		recvs_to_post;
312 
313 	/* Receives that are waiting for a request object */
314 	STAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
315 
316 	/* Queue to track free requests */
317 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	free_queue;
318 };
319 
320 typedef void (*spdk_nvmf_rdma_qpair_ibv_event)(struct spdk_nvmf_rdma_qpair *rqpair);
321 
322 struct spdk_nvmf_rdma_ibv_event_ctx {
323 	struct spdk_nvmf_rdma_qpair			*rqpair;
324 	spdk_nvmf_rdma_qpair_ibv_event			cb_fn;
325 	/* Link to other ibv events associated with this qpair */
326 	STAILQ_ENTRY(spdk_nvmf_rdma_ibv_event_ctx)	link;
327 };
328 
329 struct spdk_nvmf_rdma_qpair {
330 	struct spdk_nvmf_qpair			qpair;
331 
332 	struct spdk_nvmf_rdma_device		*device;
333 	struct spdk_nvmf_rdma_poller		*poller;
334 
335 	struct spdk_rdma_qp			*rdma_qp;
336 	struct rdma_cm_id			*cm_id;
337 	struct ibv_srq				*srq;
338 	struct rdma_cm_id			*listen_id;
339 
340 	/* The maximum number of I/O outstanding on this connection at one time */
341 	uint16_t				max_queue_depth;
342 
343 	/* The maximum number of active RDMA READ and ATOMIC operations at one time */
344 	uint16_t				max_read_depth;
345 
346 	/* The maximum number of RDMA SEND operations at one time */
347 	uint32_t				max_send_depth;
348 
349 	/* The current number of outstanding WRs from this qpair's
350 	 * recv queue. Should not exceed device->attr.max_queue_depth.
351 	 */
352 	uint16_t				current_recv_depth;
353 
354 	/* The current number of active RDMA READ operations */
355 	uint16_t				current_read_depth;
356 
357 	/* The current number of posted WRs from this qpair's
358 	 * send queue. Should not exceed max_send_depth.
359 	 */
360 	uint32_t				current_send_depth;
361 
362 	/* The maximum number of SGEs per WR on the send queue */
363 	uint32_t				max_send_sge;
364 
365 	/* The maximum number of SGEs per WR on the recv queue */
366 	uint32_t				max_recv_sge;
367 
368 	struct spdk_nvmf_rdma_resources		*resources;
369 
370 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_read_queue;
371 
372 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_write_queue;
373 
374 	/* Number of requests not in the free state */
375 	uint32_t				qd;
376 
377 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	link;
378 
379 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	recv_link;
380 
381 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	send_link;
382 
383 	/* IBV queue pair attributes: they are used to manage
384 	 * qp state and recover from errors.
385 	 */
386 	enum ibv_qp_state			ibv_state;
387 
388 	/*
389 	 * io_channel which is used to destroy qpair when it is removed from poll group
390 	 */
391 	struct spdk_io_channel		*destruct_channel;
392 
393 	/* List of ibv async events */
394 	STAILQ_HEAD(, spdk_nvmf_rdma_ibv_event_ctx)	ibv_events;
395 
396 	/* Lets us know that we have received the last_wqe event. */
397 	bool					last_wqe_reached;
398 
399 	/* Indicate that nvmf_rdma_close_qpair is called */
400 	bool					to_close;
401 };
402 
403 struct spdk_nvmf_rdma_poller_stat {
404 	uint64_t				completions;
405 	uint64_t				polls;
406 	uint64_t				requests;
407 	uint64_t				request_latency;
408 	uint64_t				pending_free_request;
409 	uint64_t				pending_rdma_read;
410 	uint64_t				pending_rdma_write;
411 };
412 
413 struct spdk_nvmf_rdma_poller {
414 	struct spdk_nvmf_rdma_device		*device;
415 	struct spdk_nvmf_rdma_poll_group	*group;
416 
417 	int					num_cqe;
418 	int					required_num_wr;
419 	struct ibv_cq				*cq;
420 
421 	/* The maximum number of I/O outstanding on the shared receive queue at one time */
422 	uint16_t				max_srq_depth;
423 
424 	/* Shared receive queue */
425 	struct ibv_srq				*srq;
426 
427 	struct spdk_nvmf_rdma_resources		*resources;
428 	struct spdk_nvmf_rdma_poller_stat	stat;
429 
430 	TAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs;
431 
432 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_recv;
433 
434 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_send;
435 
436 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
437 };
438 
439 struct spdk_nvmf_rdma_poll_group_stat {
440 	uint64_t				pending_data_buffer;
441 };
442 
443 struct spdk_nvmf_rdma_poll_group {
444 	struct spdk_nvmf_transport_poll_group		group;
445 	struct spdk_nvmf_rdma_poll_group_stat		stat;
446 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)		pollers;
447 	TAILQ_ENTRY(spdk_nvmf_rdma_poll_group)		link;
448 };
449 
450 struct spdk_nvmf_rdma_conn_sched {
451 	struct spdk_nvmf_rdma_poll_group *next_admin_pg;
452 	struct spdk_nvmf_rdma_poll_group *next_io_pg;
453 };
454 
455 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
456 struct spdk_nvmf_rdma_device {
457 	struct ibv_device_attr			attr;
458 	struct ibv_context			*context;
459 
460 	struct spdk_rdma_mem_map		*map;
461 	struct ibv_pd				*pd;
462 
463 	int					num_srq;
464 
465 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
466 };
467 
468 struct spdk_nvmf_rdma_port {
469 	const struct spdk_nvme_transport_id	*trid;
470 	struct rdma_cm_id			*id;
471 	struct spdk_nvmf_rdma_device		*device;
472 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
473 };
474 
475 struct rdma_transport_opts {
476 	uint32_t	max_srq_depth;
477 	bool		no_srq;
478 	bool		no_wr_batching;
479 	int		acceptor_backlog;
480 };
481 
482 struct spdk_nvmf_rdma_transport {
483 	struct spdk_nvmf_transport	transport;
484 	struct rdma_transport_opts	rdma_opts;
485 
486 	struct spdk_nvmf_rdma_conn_sched conn_sched;
487 
488 	struct rdma_event_channel	*event_channel;
489 
490 	struct spdk_mempool		*data_wr_pool;
491 
492 	pthread_mutex_t			lock;
493 
494 	/* fields used to poll RDMA/IB events */
495 	nfds_t			npoll_fds;
496 	struct pollfd		*poll_fds;
497 
498 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
499 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
500 	TAILQ_HEAD(, spdk_nvmf_rdma_poll_group)	poll_groups;
501 };
502 
503 static const struct spdk_json_object_decoder rdma_transport_opts_decoder[] = {
504 	{
505 		"max_srq_depth", offsetof(struct rdma_transport_opts, max_srq_depth),
506 		spdk_json_decode_uint32, true
507 	},
508 	{
509 		"no_srq", offsetof(struct rdma_transport_opts, no_srq),
510 		spdk_json_decode_bool, true
511 	},
512 	{
513 		"no_wr_batching", offsetof(struct rdma_transport_opts, no_wr_batching),
514 		spdk_json_decode_bool, true
515 	},
516 	{
517 		"acceptor_backlog", offsetof(struct rdma_transport_opts, acceptor_backlog),
518 		spdk_json_decode_int32, true
519 	},
520 };
521 
522 static bool
523 nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
524 			  struct spdk_nvmf_rdma_request *rdma_req);
525 
526 static void
527 _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
528 		     struct spdk_nvmf_rdma_poller *rpoller);
529 
530 static void
531 _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
532 		     struct spdk_nvmf_rdma_poller *rpoller);
533 
534 static inline int
535 nvmf_rdma_check_ibv_state(enum ibv_qp_state state)
536 {
537 	switch (state) {
538 	case IBV_QPS_RESET:
539 	case IBV_QPS_INIT:
540 	case IBV_QPS_RTR:
541 	case IBV_QPS_RTS:
542 	case IBV_QPS_SQD:
543 	case IBV_QPS_SQE:
544 	case IBV_QPS_ERR:
545 		return 0;
546 	default:
547 		return -1;
548 	}
549 }
550 
551 static inline enum spdk_nvme_media_error_status_code
552 nvmf_rdma_dif_error_to_compl_status(uint8_t err_type) {
553 	enum spdk_nvme_media_error_status_code result;
554 	switch (err_type)
555 	{
556 	case SPDK_DIF_REFTAG_ERROR:
557 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
558 		break;
559 	case SPDK_DIF_APPTAG_ERROR:
560 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
561 		break;
562 	case SPDK_DIF_GUARD_ERROR:
563 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
564 		break;
565 	default:
566 		SPDK_UNREACHABLE();
567 	}
568 
569 	return result;
570 }
571 
572 static enum ibv_qp_state
573 nvmf_rdma_update_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair) {
574 	enum ibv_qp_state old_state, new_state;
575 	struct ibv_qp_attr qp_attr;
576 	struct ibv_qp_init_attr init_attr;
577 	int rc;
578 
579 	old_state = rqpair->ibv_state;
580 	rc = ibv_query_qp(rqpair->rdma_qp->qp, &qp_attr,
581 			  g_spdk_nvmf_ibv_query_mask, &init_attr);
582 
583 	if (rc)
584 	{
585 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
586 		return IBV_QPS_ERR + 1;
587 	}
588 
589 	new_state = qp_attr.qp_state;
590 	rqpair->ibv_state = new_state;
591 	qp_attr.ah_attr.port_num = qp_attr.port_num;
592 
593 	rc = nvmf_rdma_check_ibv_state(new_state);
594 	if (rc)
595 	{
596 		SPDK_ERRLOG("QP#%d: bad state updated: %u, maybe hardware issue\n", rqpair->qpair.qid, new_state);
597 		/*
598 		 * IBV_QPS_UNKNOWN undefined if lib version smaller than libibverbs-1.1.8
599 		 * IBV_QPS_UNKNOWN is the enum element after IBV_QPS_ERR
600 		 */
601 		return IBV_QPS_ERR + 1;
602 	}
603 
604 	if (old_state != new_state)
605 	{
606 		spdk_trace_record(TRACE_RDMA_QP_STATE_CHANGE, 0, 0,
607 				  (uintptr_t)rqpair->cm_id, new_state);
608 	}
609 	return new_state;
610 }
611 
612 static void
613 nvmf_rdma_request_free_data(struct spdk_nvmf_rdma_request *rdma_req,
614 			    struct spdk_nvmf_rdma_transport *rtransport)
615 {
616 	struct spdk_nvmf_rdma_request_data	*data_wr;
617 	struct ibv_send_wr			*next_send_wr;
618 	uint64_t				req_wrid;
619 
620 	rdma_req->num_outstanding_data_wr = 0;
621 	data_wr = &rdma_req->data;
622 	req_wrid = data_wr->wr.wr_id;
623 	while (data_wr && data_wr->wr.wr_id == req_wrid) {
624 		memset(data_wr->sgl, 0, sizeof(data_wr->wr.sg_list[0]) * data_wr->wr.num_sge);
625 		data_wr->wr.num_sge = 0;
626 		next_send_wr = data_wr->wr.next;
627 		if (data_wr != &rdma_req->data) {
628 			spdk_mempool_put(rtransport->data_wr_pool, data_wr);
629 		}
630 		data_wr = (!next_send_wr || next_send_wr == &rdma_req->rsp.wr) ? NULL :
631 			  SPDK_CONTAINEROF(next_send_wr, struct spdk_nvmf_rdma_request_data, wr);
632 	}
633 }
634 
635 static void
636 nvmf_rdma_dump_request(struct spdk_nvmf_rdma_request *req)
637 {
638 	SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", req->req.data_from_pool);
639 	if (req->req.cmd) {
640 		SPDK_ERRLOG("\t\tRequest opcode: %d\n", req->req.cmd->nvmf_cmd.opcode);
641 	}
642 	if (req->recv) {
643 		SPDK_ERRLOG("\t\tRequest recv wr_id%lu\n", req->recv->wr.wr_id);
644 	}
645 }
646 
647 static void
648 nvmf_rdma_dump_qpair_contents(struct spdk_nvmf_rdma_qpair *rqpair)
649 {
650 	int i;
651 
652 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", rqpair->qpair.qid);
653 	for (i = 0; i < rqpair->max_queue_depth; i++) {
654 		if (rqpair->resources->reqs[i].state != RDMA_REQUEST_STATE_FREE) {
655 			nvmf_rdma_dump_request(&rqpair->resources->reqs[i]);
656 		}
657 	}
658 }
659 
660 static void
661 nvmf_rdma_resources_destroy(struct spdk_nvmf_rdma_resources *resources)
662 {
663 	if (resources->cmds_mr) {
664 		ibv_dereg_mr(resources->cmds_mr);
665 	}
666 
667 	if (resources->cpls_mr) {
668 		ibv_dereg_mr(resources->cpls_mr);
669 	}
670 
671 	if (resources->bufs_mr) {
672 		ibv_dereg_mr(resources->bufs_mr);
673 	}
674 
675 	spdk_free(resources->cmds);
676 	spdk_free(resources->cpls);
677 	spdk_free(resources->bufs);
678 	free(resources->reqs);
679 	free(resources->recvs);
680 	free(resources);
681 }
682 
683 
684 static struct spdk_nvmf_rdma_resources *
685 nvmf_rdma_resources_create(struct spdk_nvmf_rdma_resource_opts *opts)
686 {
687 	struct spdk_nvmf_rdma_resources	*resources;
688 	struct spdk_nvmf_rdma_request	*rdma_req;
689 	struct spdk_nvmf_rdma_recv	*rdma_recv;
690 	struct ibv_qp			*qp;
691 	struct ibv_srq			*srq;
692 	uint32_t			i;
693 	int				rc;
694 
695 	resources = calloc(1, sizeof(struct spdk_nvmf_rdma_resources));
696 	if (!resources) {
697 		SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
698 		return NULL;
699 	}
700 
701 	resources->reqs = calloc(opts->max_queue_depth, sizeof(*resources->reqs));
702 	resources->recvs = calloc(opts->max_queue_depth, sizeof(*resources->recvs));
703 	resources->cmds = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cmds),
704 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
705 	resources->cpls = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cpls),
706 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
707 
708 	if (opts->in_capsule_data_size > 0) {
709 		resources->bufs = spdk_zmalloc(opts->max_queue_depth * opts->in_capsule_data_size,
710 					       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY,
711 					       SPDK_MALLOC_DMA);
712 	}
713 
714 	if (!resources->reqs || !resources->recvs || !resources->cmds ||
715 	    !resources->cpls || (opts->in_capsule_data_size && !resources->bufs)) {
716 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
717 		goto cleanup;
718 	}
719 
720 	resources->cmds_mr = ibv_reg_mr(opts->pd, resources->cmds,
721 					opts->max_queue_depth * sizeof(*resources->cmds),
722 					IBV_ACCESS_LOCAL_WRITE);
723 	resources->cpls_mr = ibv_reg_mr(opts->pd, resources->cpls,
724 					opts->max_queue_depth * sizeof(*resources->cpls),
725 					0);
726 
727 	if (opts->in_capsule_data_size) {
728 		resources->bufs_mr = ibv_reg_mr(opts->pd, resources->bufs,
729 						opts->max_queue_depth *
730 						opts->in_capsule_data_size,
731 						IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
732 	}
733 
734 	if (!resources->cmds_mr || !resources->cpls_mr ||
735 	    (opts->in_capsule_data_size &&
736 	     !resources->bufs_mr)) {
737 		goto cleanup;
738 	}
739 	SPDK_DEBUGLOG(rdma, "Command Array: %p Length: %lx LKey: %x\n",
740 		      resources->cmds, opts->max_queue_depth * sizeof(*resources->cmds),
741 		      resources->cmds_mr->lkey);
742 	SPDK_DEBUGLOG(rdma, "Completion Array: %p Length: %lx LKey: %x\n",
743 		      resources->cpls, opts->max_queue_depth * sizeof(*resources->cpls),
744 		      resources->cpls_mr->lkey);
745 	if (resources->bufs && resources->bufs_mr) {
746 		SPDK_DEBUGLOG(rdma, "In Capsule Data Array: %p Length: %x LKey: %x\n",
747 			      resources->bufs, opts->max_queue_depth *
748 			      opts->in_capsule_data_size, resources->bufs_mr->lkey);
749 	}
750 
751 	/* Initialize queues */
752 	STAILQ_INIT(&resources->incoming_queue);
753 	STAILQ_INIT(&resources->free_queue);
754 
755 	for (i = 0; i < opts->max_queue_depth; i++) {
756 		struct ibv_recv_wr *bad_wr = NULL;
757 
758 		rdma_recv = &resources->recvs[i];
759 		rdma_recv->qpair = opts->qpair;
760 
761 		/* Set up memory to receive commands */
762 		if (resources->bufs) {
763 			rdma_recv->buf = (void *)((uintptr_t)resources->bufs + (i *
764 						  opts->in_capsule_data_size));
765 		}
766 
767 		rdma_recv->rdma_wr.type = RDMA_WR_TYPE_RECV;
768 
769 		rdma_recv->sgl[0].addr = (uintptr_t)&resources->cmds[i];
770 		rdma_recv->sgl[0].length = sizeof(resources->cmds[i]);
771 		rdma_recv->sgl[0].lkey = resources->cmds_mr->lkey;
772 		rdma_recv->wr.num_sge = 1;
773 
774 		if (rdma_recv->buf && resources->bufs_mr) {
775 			rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
776 			rdma_recv->sgl[1].length = opts->in_capsule_data_size;
777 			rdma_recv->sgl[1].lkey = resources->bufs_mr->lkey;
778 			rdma_recv->wr.num_sge++;
779 		}
780 
781 		rdma_recv->wr.wr_id = (uintptr_t)&rdma_recv->rdma_wr;
782 		rdma_recv->wr.sg_list = rdma_recv->sgl;
783 		if (opts->shared) {
784 			srq = (struct ibv_srq *)opts->qp;
785 			rc = ibv_post_srq_recv(srq, &rdma_recv->wr, &bad_wr);
786 		} else {
787 			qp = (struct ibv_qp *)opts->qp;
788 			rc = ibv_post_recv(qp, &rdma_recv->wr, &bad_wr);
789 		}
790 		if (rc) {
791 			goto cleanup;
792 		}
793 	}
794 
795 	for (i = 0; i < opts->max_queue_depth; i++) {
796 		rdma_req = &resources->reqs[i];
797 
798 		if (opts->qpair != NULL) {
799 			rdma_req->req.qpair = &opts->qpair->qpair;
800 		} else {
801 			rdma_req->req.qpair = NULL;
802 		}
803 		rdma_req->req.cmd = NULL;
804 
805 		/* Set up memory to send responses */
806 		rdma_req->req.rsp = &resources->cpls[i];
807 
808 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&resources->cpls[i];
809 		rdma_req->rsp.sgl[0].length = sizeof(resources->cpls[i]);
810 		rdma_req->rsp.sgl[0].lkey = resources->cpls_mr->lkey;
811 
812 		rdma_req->rsp.rdma_wr.type = RDMA_WR_TYPE_SEND;
813 		rdma_req->rsp.wr.wr_id = (uintptr_t)&rdma_req->rsp.rdma_wr;
814 		rdma_req->rsp.wr.next = NULL;
815 		rdma_req->rsp.wr.opcode = IBV_WR_SEND;
816 		rdma_req->rsp.wr.send_flags = IBV_SEND_SIGNALED;
817 		rdma_req->rsp.wr.sg_list = rdma_req->rsp.sgl;
818 		rdma_req->rsp.wr.num_sge = SPDK_COUNTOF(rdma_req->rsp.sgl);
819 
820 		/* Set up memory for data buffers */
821 		rdma_req->data.rdma_wr.type = RDMA_WR_TYPE_DATA;
822 		rdma_req->data.wr.wr_id = (uintptr_t)&rdma_req->data.rdma_wr;
823 		rdma_req->data.wr.next = NULL;
824 		rdma_req->data.wr.send_flags = IBV_SEND_SIGNALED;
825 		rdma_req->data.wr.sg_list = rdma_req->data.sgl;
826 		rdma_req->data.wr.num_sge = SPDK_COUNTOF(rdma_req->data.sgl);
827 
828 		/* Initialize request state to FREE */
829 		rdma_req->state = RDMA_REQUEST_STATE_FREE;
830 		STAILQ_INSERT_TAIL(&resources->free_queue, rdma_req, state_link);
831 	}
832 
833 	return resources;
834 
835 cleanup:
836 	nvmf_rdma_resources_destroy(resources);
837 	return NULL;
838 }
839 
840 static void
841 nvmf_rdma_qpair_clean_ibv_events(struct spdk_nvmf_rdma_qpair *rqpair)
842 {
843 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx, *tctx;
844 	STAILQ_FOREACH_SAFE(ctx, &rqpair->ibv_events, link, tctx) {
845 		ctx->rqpair = NULL;
846 		/* Memory allocated for ctx is freed in nvmf_rdma_qpair_process_ibv_event */
847 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
848 	}
849 }
850 
851 static void
852 nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
853 {
854 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
855 	struct ibv_recv_wr		*bad_recv_wr = NULL;
856 	int				rc;
857 
858 	spdk_trace_record(TRACE_RDMA_QP_DESTROY, 0, 0, (uintptr_t)rqpair->cm_id, 0);
859 
860 	if (rqpair->qd != 0) {
861 		struct spdk_nvmf_qpair *qpair = &rqpair->qpair;
862 		struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(qpair->transport,
863 				struct spdk_nvmf_rdma_transport, transport);
864 		struct spdk_nvmf_rdma_request *req;
865 		uint32_t i, max_req_count = 0;
866 
867 		SPDK_WARNLOG("Destroying qpair when queue depth is %d\n", rqpair->qd);
868 
869 		if (rqpair->srq == NULL) {
870 			nvmf_rdma_dump_qpair_contents(rqpair);
871 			max_req_count = rqpair->max_queue_depth;
872 		} else if (rqpair->poller && rqpair->resources) {
873 			max_req_count = rqpair->poller->max_srq_depth;
874 		}
875 
876 		SPDK_DEBUGLOG(rdma, "Release incomplete requests\n");
877 		for (i = 0; i < max_req_count; i++) {
878 			req = &rqpair->resources->reqs[i];
879 			if (req->req.qpair == qpair && req->state != RDMA_REQUEST_STATE_FREE) {
880 				/* nvmf_rdma_request_process checks qpair ibv and internal state
881 				 * and completes a request */
882 				nvmf_rdma_request_process(rtransport, req);
883 			}
884 		}
885 		assert(rqpair->qd == 0);
886 	}
887 
888 	if (rqpair->poller) {
889 		TAILQ_REMOVE(&rqpair->poller->qpairs, rqpair, link);
890 
891 		if (rqpair->srq != NULL && rqpair->resources != NULL) {
892 			/* Drop all received but unprocessed commands for this queue and return them to SRQ */
893 			STAILQ_FOREACH_SAFE(rdma_recv, &rqpair->resources->incoming_queue, link, recv_tmp) {
894 				if (rqpair == rdma_recv->qpair) {
895 					STAILQ_REMOVE(&rqpair->resources->incoming_queue, rdma_recv, spdk_nvmf_rdma_recv, link);
896 					rc = ibv_post_srq_recv(rqpair->srq, &rdma_recv->wr, &bad_recv_wr);
897 					if (rc) {
898 						SPDK_ERRLOG("Unable to re-post rx descriptor\n");
899 					}
900 				}
901 			}
902 		}
903 	}
904 
905 	if (rqpair->cm_id) {
906 		if (rqpair->rdma_qp != NULL) {
907 			spdk_rdma_qp_destroy(rqpair->rdma_qp);
908 			rqpair->rdma_qp = NULL;
909 		}
910 		rdma_destroy_id(rqpair->cm_id);
911 
912 		if (rqpair->poller != NULL && rqpair->srq == NULL) {
913 			rqpair->poller->required_num_wr -= MAX_WR_PER_QP(rqpair->max_queue_depth);
914 		}
915 	}
916 
917 	if (rqpair->srq == NULL && rqpair->resources != NULL) {
918 		nvmf_rdma_resources_destroy(rqpair->resources);
919 	}
920 
921 	nvmf_rdma_qpair_clean_ibv_events(rqpair);
922 
923 	if (rqpair->destruct_channel) {
924 		spdk_put_io_channel(rqpair->destruct_channel);
925 		rqpair->destruct_channel = NULL;
926 	}
927 
928 	free(rqpair);
929 }
930 
931 static int
932 nvmf_rdma_resize_cq(struct spdk_nvmf_rdma_qpair *rqpair, struct spdk_nvmf_rdma_device *device)
933 {
934 	struct spdk_nvmf_rdma_poller	*rpoller;
935 	int				rc, num_cqe, required_num_wr;
936 
937 	/* Enlarge CQ size dynamically */
938 	rpoller = rqpair->poller;
939 	required_num_wr = rpoller->required_num_wr + MAX_WR_PER_QP(rqpair->max_queue_depth);
940 	num_cqe = rpoller->num_cqe;
941 	if (num_cqe < required_num_wr) {
942 		num_cqe = spdk_max(num_cqe * 2, required_num_wr);
943 		num_cqe = spdk_min(num_cqe, device->attr.max_cqe);
944 	}
945 
946 	if (rpoller->num_cqe != num_cqe) {
947 		if (device->context->device->transport_type == IBV_TRANSPORT_IWARP) {
948 			SPDK_ERRLOG("iWARP doesn't support CQ resize. Current capacity %u, required %u\n"
949 				    "Using CQ of insufficient size may lead to CQ overrun\n", rpoller->num_cqe, num_cqe);
950 			return -1;
951 		}
952 		if (required_num_wr > device->attr.max_cqe) {
953 			SPDK_ERRLOG("RDMA CQE requirement (%d) exceeds device max_cqe limitation (%d)\n",
954 				    required_num_wr, device->attr.max_cqe);
955 			return -1;
956 		}
957 
958 		SPDK_DEBUGLOG(rdma, "Resize RDMA CQ from %d to %d\n", rpoller->num_cqe, num_cqe);
959 		rc = ibv_resize_cq(rpoller->cq, num_cqe);
960 		if (rc) {
961 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
962 			return -1;
963 		}
964 
965 		rpoller->num_cqe = num_cqe;
966 	}
967 
968 	rpoller->required_num_wr = required_num_wr;
969 	return 0;
970 }
971 
972 static int
973 nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
974 {
975 	struct spdk_nvmf_rdma_qpair		*rqpair;
976 	struct spdk_nvmf_rdma_transport		*rtransport;
977 	struct spdk_nvmf_transport		*transport;
978 	struct spdk_nvmf_rdma_resource_opts	opts;
979 	struct spdk_nvmf_rdma_device		*device;
980 	struct spdk_rdma_qp_init_attr		qp_init_attr = {};
981 
982 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
983 	device = rqpair->device;
984 
985 	qp_init_attr.qp_context	= rqpair;
986 	qp_init_attr.pd		= device->pd;
987 	qp_init_attr.send_cq	= rqpair->poller->cq;
988 	qp_init_attr.recv_cq	= rqpair->poller->cq;
989 
990 	if (rqpair->srq) {
991 		qp_init_attr.srq		= rqpair->srq;
992 	} else {
993 		qp_init_attr.cap.max_recv_wr	= rqpair->max_queue_depth;
994 	}
995 
996 	/* SEND, READ, and WRITE operations */
997 	qp_init_attr.cap.max_send_wr	= (uint32_t)rqpair->max_queue_depth * 2;
998 	qp_init_attr.cap.max_send_sge	= spdk_min((uint32_t)device->attr.max_sge, NVMF_DEFAULT_TX_SGE);
999 	qp_init_attr.cap.max_recv_sge	= spdk_min((uint32_t)device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
1000 
1001 	if (rqpair->srq == NULL && nvmf_rdma_resize_cq(rqpair, device) < 0) {
1002 		SPDK_ERRLOG("Failed to resize the completion queue. Cannot initialize qpair.\n");
1003 		goto error;
1004 	}
1005 
1006 	rqpair->rdma_qp = spdk_rdma_qp_create(rqpair->cm_id, &qp_init_attr);
1007 	if (!rqpair->rdma_qp) {
1008 		goto error;
1009 	}
1010 
1011 	rqpair->max_send_depth = spdk_min((uint32_t)(rqpair->max_queue_depth * 2),
1012 					  qp_init_attr.cap.max_send_wr);
1013 	rqpair->max_send_sge = spdk_min(NVMF_DEFAULT_TX_SGE, qp_init_attr.cap.max_send_sge);
1014 	rqpair->max_recv_sge = spdk_min(NVMF_DEFAULT_RX_SGE, qp_init_attr.cap.max_recv_sge);
1015 	spdk_trace_record(TRACE_RDMA_QP_CREATE, 0, 0, (uintptr_t)rqpair->cm_id, 0);
1016 	SPDK_DEBUGLOG(rdma, "New RDMA Connection: %p\n", qpair);
1017 
1018 	if (rqpair->poller->srq == NULL) {
1019 		rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
1020 		transport = &rtransport->transport;
1021 
1022 		opts.qp = rqpair->rdma_qp->qp;
1023 		opts.pd = rqpair->cm_id->pd;
1024 		opts.qpair = rqpair;
1025 		opts.shared = false;
1026 		opts.max_queue_depth = rqpair->max_queue_depth;
1027 		opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
1028 
1029 		rqpair->resources = nvmf_rdma_resources_create(&opts);
1030 
1031 		if (!rqpair->resources) {
1032 			SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
1033 			rdma_destroy_qp(rqpair->cm_id);
1034 			goto error;
1035 		}
1036 	} else {
1037 		rqpair->resources = rqpair->poller->resources;
1038 	}
1039 
1040 	rqpair->current_recv_depth = 0;
1041 	STAILQ_INIT(&rqpair->pending_rdma_read_queue);
1042 	STAILQ_INIT(&rqpair->pending_rdma_write_queue);
1043 
1044 	return 0;
1045 
1046 error:
1047 	rdma_destroy_id(rqpair->cm_id);
1048 	rqpair->cm_id = NULL;
1049 	return -1;
1050 }
1051 
1052 /* Append the given recv wr structure to the resource structs outstanding recvs list. */
1053 /* This function accepts either a single wr or the first wr in a linked list. */
1054 static void
1055 nvmf_rdma_qpair_queue_recv_wrs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *first)
1056 {
1057 	struct ibv_recv_wr *last;
1058 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
1059 			struct spdk_nvmf_rdma_transport, transport);
1060 
1061 	last = first;
1062 	while (last->next != NULL) {
1063 		last = last->next;
1064 	}
1065 
1066 	if (rqpair->resources->recvs_to_post.first == NULL) {
1067 		rqpair->resources->recvs_to_post.first = first;
1068 		rqpair->resources->recvs_to_post.last = last;
1069 		if (rqpair->srq == NULL) {
1070 			STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_recv, rqpair, recv_link);
1071 		}
1072 	} else {
1073 		rqpair->resources->recvs_to_post.last->next = first;
1074 		rqpair->resources->recvs_to_post.last = last;
1075 	}
1076 
1077 	if (rtransport->rdma_opts.no_wr_batching) {
1078 		_poller_submit_recvs(rtransport, rqpair->poller);
1079 	}
1080 }
1081 
1082 static int
1083 request_transfer_in(struct spdk_nvmf_request *req)
1084 {
1085 	struct spdk_nvmf_rdma_request	*rdma_req;
1086 	struct spdk_nvmf_qpair		*qpair;
1087 	struct spdk_nvmf_rdma_qpair	*rqpair;
1088 	struct spdk_nvmf_rdma_transport *rtransport;
1089 
1090 	qpair = req->qpair;
1091 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1092 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1093 	rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
1094 				      struct spdk_nvmf_rdma_transport, transport);
1095 
1096 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
1097 	assert(rdma_req != NULL);
1098 
1099 	if (spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, &rdma_req->data.wr)) {
1100 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1101 	}
1102 	if (rtransport->rdma_opts.no_wr_batching) {
1103 		_poller_submit_sends(rtransport, rqpair->poller);
1104 	}
1105 
1106 	rqpair->current_read_depth += rdma_req->num_outstanding_data_wr;
1107 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr;
1108 	return 0;
1109 }
1110 
1111 static int
1112 request_transfer_out(struct spdk_nvmf_request *req, int *data_posted)
1113 {
1114 	int				num_outstanding_data_wr = 0;
1115 	struct spdk_nvmf_rdma_request	*rdma_req;
1116 	struct spdk_nvmf_qpair		*qpair;
1117 	struct spdk_nvmf_rdma_qpair	*rqpair;
1118 	struct spdk_nvme_cpl		*rsp;
1119 	struct ibv_send_wr		*first = NULL;
1120 	struct spdk_nvmf_rdma_transport *rtransport;
1121 
1122 	*data_posted = 0;
1123 	qpair = req->qpair;
1124 	rsp = &req->rsp->nvme_cpl;
1125 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1126 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1127 	rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
1128 				      struct spdk_nvmf_rdma_transport, transport);
1129 
1130 	/* Advance our sq_head pointer */
1131 	if (qpair->sq_head == qpair->sq_head_max) {
1132 		qpair->sq_head = 0;
1133 	} else {
1134 		qpair->sq_head++;
1135 	}
1136 	rsp->sqhd = qpair->sq_head;
1137 
1138 	/* queue the capsule for the recv buffer */
1139 	assert(rdma_req->recv != NULL);
1140 
1141 	nvmf_rdma_qpair_queue_recv_wrs(rqpair, &rdma_req->recv->wr);
1142 
1143 	rdma_req->recv = NULL;
1144 	assert(rqpair->current_recv_depth > 0);
1145 	rqpair->current_recv_depth--;
1146 
1147 	/* Build the response which consists of optional
1148 	 * RDMA WRITEs to transfer data, plus an RDMA SEND
1149 	 * containing the response.
1150 	 */
1151 	first = &rdma_req->rsp.wr;
1152 
1153 	if (rsp->status.sc != SPDK_NVME_SC_SUCCESS) {
1154 		/* On failure, data was not read from the controller. So clear the
1155 		 * number of outstanding data WRs to zero.
1156 		 */
1157 		rdma_req->num_outstanding_data_wr = 0;
1158 	} else if (req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1159 		first = &rdma_req->data.wr;
1160 		*data_posted = 1;
1161 		num_outstanding_data_wr = rdma_req->num_outstanding_data_wr;
1162 	}
1163 	if (spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, first)) {
1164 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1165 	}
1166 	if (rtransport->rdma_opts.no_wr_batching) {
1167 		_poller_submit_sends(rtransport, rqpair->poller);
1168 	}
1169 
1170 	/* +1 for the rsp wr */
1171 	rqpair->current_send_depth += num_outstanding_data_wr + 1;
1172 
1173 	return 0;
1174 }
1175 
1176 static int
1177 nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
1178 {
1179 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
1180 	struct rdma_conn_param				ctrlr_event_data = {};
1181 	int						rc;
1182 
1183 	accept_data.recfmt = 0;
1184 	accept_data.crqsize = rqpair->max_queue_depth;
1185 
1186 	ctrlr_event_data.private_data = &accept_data;
1187 	ctrlr_event_data.private_data_len = sizeof(accept_data);
1188 	if (id->ps == RDMA_PS_TCP) {
1189 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
1190 		ctrlr_event_data.initiator_depth = rqpair->max_read_depth;
1191 	}
1192 
1193 	/* Configure infinite retries for the initiator side qpair.
1194 	 * When using a shared receive queue on the target side,
1195 	 * we need to pass this value to the initiator to prevent the
1196 	 * initiator side NIC from completing SEND requests back to the
1197 	 * initiator with status rnr_retry_count_exceeded. */
1198 	if (rqpair->srq != NULL) {
1199 		ctrlr_event_data.rnr_retry_count = 0x7;
1200 	}
1201 
1202 	/* When qpair is created without use of rdma cm API, an additional
1203 	 * information must be provided to initiator in the connection response:
1204 	 * whether qpair is using SRQ and its qp_num
1205 	 * Fields below are ignored by rdma cm if qpair has been
1206 	 * created using rdma cm API. */
1207 	ctrlr_event_data.srq = rqpair->srq ? 1 : 0;
1208 	ctrlr_event_data.qp_num = rqpair->rdma_qp->qp->qp_num;
1209 
1210 	rc = spdk_rdma_qp_accept(rqpair->rdma_qp, &ctrlr_event_data);
1211 	if (rc) {
1212 		SPDK_ERRLOG("Error %d on spdk_rdma_qp_accept\n", errno);
1213 	} else {
1214 		SPDK_DEBUGLOG(rdma, "Sent back the accept\n");
1215 	}
1216 
1217 	return rc;
1218 }
1219 
1220 static void
1221 nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
1222 {
1223 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
1224 
1225 	rej_data.recfmt = 0;
1226 	rej_data.sts = error;
1227 
1228 	rdma_reject(id, &rej_data, sizeof(rej_data));
1229 }
1230 
1231 static int
1232 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event)
1233 {
1234 	struct spdk_nvmf_rdma_transport *rtransport;
1235 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
1236 	struct spdk_nvmf_rdma_port	*port;
1237 	struct rdma_conn_param		*rdma_param = NULL;
1238 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
1239 	uint16_t			max_queue_depth;
1240 	uint16_t			max_read_depth;
1241 
1242 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1243 
1244 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
1245 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
1246 
1247 	rdma_param = &event->param.conn;
1248 	if (rdma_param->private_data == NULL ||
1249 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1250 		SPDK_ERRLOG("connect request: no private data provided\n");
1251 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
1252 		return -1;
1253 	}
1254 
1255 	private_data = rdma_param->private_data;
1256 	if (private_data->recfmt != 0) {
1257 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
1258 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
1259 		return -1;
1260 	}
1261 
1262 	SPDK_DEBUGLOG(rdma, "Connect Recv on fabric intf name %s, dev_name %s\n",
1263 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
1264 
1265 	port = event->listen_id->context;
1266 	SPDK_DEBUGLOG(rdma, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
1267 		      event->listen_id, event->listen_id->verbs, port);
1268 
1269 	/* Figure out the supported queue depth. This is a multi-step process
1270 	 * that takes into account hardware maximums, host provided values,
1271 	 * and our target's internal memory limits */
1272 
1273 	SPDK_DEBUGLOG(rdma, "Calculating Queue Depth\n");
1274 
1275 	/* Start with the maximum queue depth allowed by the target */
1276 	max_queue_depth = rtransport->transport.opts.max_queue_depth;
1277 	max_read_depth = rtransport->transport.opts.max_queue_depth;
1278 	SPDK_DEBUGLOG(rdma, "Target Max Queue Depth: %d\n",
1279 		      rtransport->transport.opts.max_queue_depth);
1280 
1281 	/* Next check the local NIC's hardware limitations */
1282 	SPDK_DEBUGLOG(rdma,
1283 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
1284 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
1285 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
1286 	max_read_depth = spdk_min(max_read_depth, port->device->attr.max_qp_init_rd_atom);
1287 
1288 	/* Next check the remote NIC's hardware limitations */
1289 	SPDK_DEBUGLOG(rdma,
1290 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
1291 		      rdma_param->initiator_depth, rdma_param->responder_resources);
1292 	if (rdma_param->initiator_depth > 0) {
1293 		max_read_depth = spdk_min(max_read_depth, rdma_param->initiator_depth);
1294 	}
1295 
1296 	/* Finally check for the host software requested values, which are
1297 	 * optional. */
1298 	if (rdma_param->private_data != NULL &&
1299 	    rdma_param->private_data_len >= sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1300 		SPDK_DEBUGLOG(rdma, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1301 		SPDK_DEBUGLOG(rdma, "Host Send Queue Size: %d\n", private_data->hsqsize);
1302 		max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
1303 		max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
1304 	}
1305 
1306 	SPDK_DEBUGLOG(rdma, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
1307 		      max_queue_depth, max_read_depth);
1308 
1309 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
1310 	if (rqpair == NULL) {
1311 		SPDK_ERRLOG("Could not allocate new connection.\n");
1312 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1313 		return -1;
1314 	}
1315 
1316 	rqpair->device = port->device;
1317 	rqpair->max_queue_depth = max_queue_depth;
1318 	rqpair->max_read_depth = max_read_depth;
1319 	rqpair->cm_id = event->id;
1320 	rqpair->listen_id = event->listen_id;
1321 	rqpair->qpair.transport = transport;
1322 	STAILQ_INIT(&rqpair->ibv_events);
1323 	/* use qid from the private data to determine the qpair type
1324 	   qid will be set to the appropriate value when the controller is created */
1325 	rqpair->qpair.qid = private_data->qid;
1326 
1327 	event->id->context = &rqpair->qpair;
1328 
1329 	spdk_nvmf_tgt_new_qpair(transport->tgt, &rqpair->qpair);
1330 
1331 	return 0;
1332 }
1333 
1334 static inline void
1335 nvmf_rdma_setup_wr(struct ibv_send_wr *wr, struct ibv_send_wr *next,
1336 		   enum spdk_nvme_data_transfer xfer)
1337 {
1338 	if (xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1339 		wr->opcode = IBV_WR_RDMA_WRITE;
1340 		wr->send_flags = 0;
1341 		wr->next = next;
1342 	} else if (xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1343 		wr->opcode = IBV_WR_RDMA_READ;
1344 		wr->send_flags = IBV_SEND_SIGNALED;
1345 		wr->next = NULL;
1346 	} else {
1347 		assert(0);
1348 	}
1349 }
1350 
1351 static int
1352 nvmf_request_alloc_wrs(struct spdk_nvmf_rdma_transport *rtransport,
1353 		       struct spdk_nvmf_rdma_request *rdma_req,
1354 		       uint32_t num_sgl_descriptors)
1355 {
1356 	struct spdk_nvmf_rdma_request_data	*work_requests[SPDK_NVMF_MAX_SGL_ENTRIES];
1357 	struct spdk_nvmf_rdma_request_data	*current_data_wr;
1358 	uint32_t				i;
1359 
1360 	if (num_sgl_descriptors > SPDK_NVMF_MAX_SGL_ENTRIES) {
1361 		SPDK_ERRLOG("Requested too much entries (%u), the limit is %u\n",
1362 			    num_sgl_descriptors, SPDK_NVMF_MAX_SGL_ENTRIES);
1363 		return -EINVAL;
1364 	}
1365 
1366 	if (spdk_mempool_get_bulk(rtransport->data_wr_pool, (void **)work_requests, num_sgl_descriptors)) {
1367 		return -ENOMEM;
1368 	}
1369 
1370 	current_data_wr = &rdma_req->data;
1371 
1372 	for (i = 0; i < num_sgl_descriptors; i++) {
1373 		nvmf_rdma_setup_wr(&current_data_wr->wr, &work_requests[i]->wr, rdma_req->req.xfer);
1374 		current_data_wr->wr.next = &work_requests[i]->wr;
1375 		current_data_wr = work_requests[i];
1376 		current_data_wr->wr.sg_list = current_data_wr->sgl;
1377 		current_data_wr->wr.wr_id = rdma_req->data.wr.wr_id;
1378 	}
1379 
1380 	nvmf_rdma_setup_wr(&current_data_wr->wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1381 
1382 	return 0;
1383 }
1384 
1385 static inline void
1386 nvmf_rdma_setup_request(struct spdk_nvmf_rdma_request *rdma_req)
1387 {
1388 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1389 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1390 
1391 	wr->wr.rdma.rkey = sgl->keyed.key;
1392 	wr->wr.rdma.remote_addr = sgl->address;
1393 	nvmf_rdma_setup_wr(wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1394 }
1395 
1396 static inline void
1397 nvmf_rdma_update_remote_addr(struct spdk_nvmf_rdma_request *rdma_req, uint32_t num_wrs)
1398 {
1399 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1400 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1401 	uint32_t			i;
1402 	int				j;
1403 	uint64_t			remote_addr_offset = 0;
1404 
1405 	for (i = 0; i < num_wrs; ++i) {
1406 		wr->wr.rdma.rkey = sgl->keyed.key;
1407 		wr->wr.rdma.remote_addr = sgl->address + remote_addr_offset;
1408 		for (j = 0; j < wr->num_sge; ++j) {
1409 			remote_addr_offset += wr->sg_list[j].length;
1410 		}
1411 		wr = wr->next;
1412 	}
1413 }
1414 
1415 static bool
1416 nvmf_rdma_fill_wr_sge(struct spdk_nvmf_rdma_device *device,
1417 		      struct iovec *iov, struct ibv_send_wr **_wr,
1418 		      uint32_t *_remaining_data_block, uint32_t *_offset,
1419 		      uint32_t *_num_extra_wrs,
1420 		      const struct spdk_dif_ctx *dif_ctx)
1421 {
1422 	struct ibv_send_wr *wr = *_wr;
1423 	struct ibv_sge	*sg_ele = &wr->sg_list[wr->num_sge];
1424 	struct spdk_rdma_memory_translation mem_translation;
1425 	int		rc;
1426 	uint32_t	lkey = 0;
1427 	uint32_t	remaining, data_block_size, md_size, sge_len;
1428 
1429 	rc = spdk_rdma_get_translation(device->map, iov->iov_base, iov->iov_len, &mem_translation);
1430 	if (spdk_unlikely(rc)) {
1431 		return false;
1432 	}
1433 
1434 	lkey = spdk_rdma_memory_translation_get_lkey(&mem_translation);
1435 
1436 	if (spdk_likely(!dif_ctx)) {
1437 		sg_ele->lkey = lkey;
1438 		sg_ele->addr = (uintptr_t)(iov->iov_base);
1439 		sg_ele->length = iov->iov_len;
1440 		wr->num_sge++;
1441 	} else {
1442 		remaining = iov->iov_len - *_offset;
1443 		data_block_size = dif_ctx->block_size - dif_ctx->md_size;
1444 		md_size = dif_ctx->md_size;
1445 
1446 		while (remaining) {
1447 			if (wr->num_sge >= SPDK_NVMF_MAX_SGL_ENTRIES) {
1448 				if (*_num_extra_wrs > 0 && wr->next) {
1449 					*_wr = wr->next;
1450 					wr = *_wr;
1451 					wr->num_sge = 0;
1452 					sg_ele = &wr->sg_list[wr->num_sge];
1453 					(*_num_extra_wrs)--;
1454 				} else {
1455 					break;
1456 				}
1457 			}
1458 			sg_ele->lkey = lkey;
1459 			sg_ele->addr = (uintptr_t)((char *)iov->iov_base + *_offset);
1460 			sge_len = spdk_min(remaining, *_remaining_data_block);
1461 			sg_ele->length = sge_len;
1462 			remaining -= sge_len;
1463 			*_remaining_data_block -= sge_len;
1464 			*_offset += sge_len;
1465 
1466 			sg_ele++;
1467 			wr->num_sge++;
1468 
1469 			if (*_remaining_data_block == 0) {
1470 				/* skip metadata */
1471 				*_offset += md_size;
1472 				/* Metadata that do not fit this IO buffer will be included in the next IO buffer */
1473 				remaining -= spdk_min(remaining, md_size);
1474 				*_remaining_data_block = data_block_size;
1475 			}
1476 
1477 			if (remaining == 0) {
1478 				/* By subtracting the size of the last IOV from the offset, we ensure that we skip
1479 				   the remaining metadata bits at the beginning of the next buffer */
1480 				*_offset -= iov->iov_len;
1481 			}
1482 		}
1483 	}
1484 
1485 	return true;
1486 }
1487 
1488 static int
1489 nvmf_rdma_fill_wr_sgl(struct spdk_nvmf_rdma_poll_group *rgroup,
1490 		      struct spdk_nvmf_rdma_device *device,
1491 		      struct spdk_nvmf_rdma_request *rdma_req,
1492 		      struct ibv_send_wr *wr,
1493 		      uint32_t length,
1494 		      uint32_t num_extra_wrs)
1495 {
1496 	struct spdk_nvmf_request *req = &rdma_req->req;
1497 	struct spdk_dif_ctx *dif_ctx = NULL;
1498 	uint32_t remaining_data_block = 0;
1499 	uint32_t offset = 0;
1500 
1501 	if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
1502 		dif_ctx = &rdma_req->req.dif.dif_ctx;
1503 		remaining_data_block = dif_ctx->block_size - dif_ctx->md_size;
1504 	}
1505 
1506 	wr->num_sge = 0;
1507 
1508 	while (length && (num_extra_wrs || wr->num_sge < SPDK_NVMF_MAX_SGL_ENTRIES)) {
1509 		if (spdk_unlikely(!nvmf_rdma_fill_wr_sge(device, &req->iov[rdma_req->iovpos], &wr,
1510 				  &remaining_data_block, &offset, &num_extra_wrs, dif_ctx))) {
1511 			return -EINVAL;
1512 		}
1513 
1514 		length -= req->iov[rdma_req->iovpos].iov_len;
1515 		rdma_req->iovpos++;
1516 	}
1517 
1518 	if (length) {
1519 		SPDK_ERRLOG("Not enough SG entries to hold data buffer\n");
1520 		return -EINVAL;
1521 	}
1522 
1523 	return 0;
1524 }
1525 
1526 static inline uint32_t
1527 nvmf_rdma_calc_num_wrs(uint32_t length, uint32_t io_unit_size, uint32_t block_size)
1528 {
1529 	/* estimate the number of SG entries and WRs needed to process the request */
1530 	uint32_t num_sge = 0;
1531 	uint32_t i;
1532 	uint32_t num_buffers = SPDK_CEIL_DIV(length, io_unit_size);
1533 
1534 	for (i = 0; i < num_buffers && length > 0; i++) {
1535 		uint32_t buffer_len = spdk_min(length, io_unit_size);
1536 		uint32_t num_sge_in_block = SPDK_CEIL_DIV(buffer_len, block_size);
1537 
1538 		if (num_sge_in_block * block_size > buffer_len) {
1539 			++num_sge_in_block;
1540 		}
1541 		num_sge += num_sge_in_block;
1542 		length -= buffer_len;
1543 	}
1544 	return SPDK_CEIL_DIV(num_sge, SPDK_NVMF_MAX_SGL_ENTRIES);
1545 }
1546 
1547 static int
1548 nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1549 			    struct spdk_nvmf_rdma_device *device,
1550 			    struct spdk_nvmf_rdma_request *rdma_req,
1551 			    uint32_t length)
1552 {
1553 	struct spdk_nvmf_rdma_qpair		*rqpair;
1554 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1555 	struct spdk_nvmf_request		*req = &rdma_req->req;
1556 	struct ibv_send_wr			*wr = &rdma_req->data.wr;
1557 	int					rc;
1558 	uint32_t				num_wrs = 1;
1559 
1560 	rqpair = SPDK_CONTAINEROF(req->qpair, struct spdk_nvmf_rdma_qpair, qpair);
1561 	rgroup = rqpair->poller->group;
1562 
1563 	/* rdma wr specifics */
1564 	nvmf_rdma_setup_request(rdma_req);
1565 
1566 	rc = spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport,
1567 					   length);
1568 	if (rc != 0) {
1569 		return rc;
1570 	}
1571 
1572 	assert(req->iovcnt <= rqpair->max_send_sge);
1573 
1574 	rdma_req->iovpos = 0;
1575 
1576 	if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1577 		num_wrs = nvmf_rdma_calc_num_wrs(length, rtransport->transport.opts.io_unit_size,
1578 						 req->dif.dif_ctx.block_size);
1579 		if (num_wrs > 1) {
1580 			rc = nvmf_request_alloc_wrs(rtransport, rdma_req, num_wrs - 1);
1581 			if (rc != 0) {
1582 				goto err_exit;
1583 			}
1584 		}
1585 	}
1586 
1587 	rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, wr, length, num_wrs - 1);
1588 	if (spdk_unlikely(rc != 0)) {
1589 		goto err_exit;
1590 	}
1591 
1592 	if (spdk_unlikely(num_wrs > 1)) {
1593 		nvmf_rdma_update_remote_addr(rdma_req, num_wrs);
1594 	}
1595 
1596 	/* set the number of outstanding data WRs for this request. */
1597 	rdma_req->num_outstanding_data_wr = num_wrs;
1598 
1599 	return rc;
1600 
1601 err_exit:
1602 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1603 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1604 	req->iovcnt = 0;
1605 	return rc;
1606 }
1607 
1608 static int
1609 nvmf_rdma_request_fill_iovs_multi_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1610 				      struct spdk_nvmf_rdma_device *device,
1611 				      struct spdk_nvmf_rdma_request *rdma_req)
1612 {
1613 	struct spdk_nvmf_rdma_qpair		*rqpair;
1614 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1615 	struct ibv_send_wr			*current_wr;
1616 	struct spdk_nvmf_request		*req = &rdma_req->req;
1617 	struct spdk_nvme_sgl_descriptor		*inline_segment, *desc;
1618 	uint32_t				num_sgl_descriptors;
1619 	uint32_t				lengths[SPDK_NVMF_MAX_SGL_ENTRIES];
1620 	uint32_t				i;
1621 	int					rc;
1622 
1623 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1624 	rgroup = rqpair->poller->group;
1625 
1626 	inline_segment = &req->cmd->nvme_cmd.dptr.sgl1;
1627 	assert(inline_segment->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT);
1628 	assert(inline_segment->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET);
1629 
1630 	num_sgl_descriptors = inline_segment->unkeyed.length / sizeof(struct spdk_nvme_sgl_descriptor);
1631 	assert(num_sgl_descriptors <= SPDK_NVMF_MAX_SGL_ENTRIES);
1632 
1633 	if (nvmf_request_alloc_wrs(rtransport, rdma_req, num_sgl_descriptors - 1) != 0) {
1634 		return -ENOMEM;
1635 	}
1636 
1637 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1638 	for (i = 0; i < num_sgl_descriptors; i++) {
1639 		if (spdk_likely(!req->dif.dif_insert_or_strip)) {
1640 			lengths[i] = desc->keyed.length;
1641 		} else {
1642 			req->dif.orig_length += desc->keyed.length;
1643 			lengths[i] = spdk_dif_get_length_with_md(desc->keyed.length, &req->dif.dif_ctx);
1644 			req->dif.elba_length += lengths[i];
1645 		}
1646 		desc++;
1647 	}
1648 
1649 	rc = spdk_nvmf_request_get_buffers_multi(req, &rgroup->group, &rtransport->transport,
1650 			lengths, num_sgl_descriptors);
1651 	if (rc != 0) {
1652 		nvmf_rdma_request_free_data(rdma_req, rtransport);
1653 		return rc;
1654 	}
1655 
1656 	/* The first WR must always be the embedded data WR. This is how we unwind them later. */
1657 	current_wr = &rdma_req->data.wr;
1658 	assert(current_wr != NULL);
1659 
1660 	req->length = 0;
1661 	rdma_req->iovpos = 0;
1662 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1663 	for (i = 0; i < num_sgl_descriptors; i++) {
1664 		/* The descriptors must be keyed data block descriptors with an address, not an offset. */
1665 		if (spdk_unlikely(desc->generic.type != SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK ||
1666 				  desc->keyed.subtype != SPDK_NVME_SGL_SUBTYPE_ADDRESS)) {
1667 			rc = -EINVAL;
1668 			goto err_exit;
1669 		}
1670 
1671 		current_wr->num_sge = 0;
1672 
1673 		rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, current_wr, lengths[i], 0);
1674 		if (rc != 0) {
1675 			rc = -ENOMEM;
1676 			goto err_exit;
1677 		}
1678 
1679 		req->length += desc->keyed.length;
1680 		current_wr->wr.rdma.rkey = desc->keyed.key;
1681 		current_wr->wr.rdma.remote_addr = desc->address;
1682 		current_wr = current_wr->next;
1683 		desc++;
1684 	}
1685 
1686 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1687 	/* Go back to the last descriptor in the list. */
1688 	desc--;
1689 	if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1690 		if (desc->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1691 			rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1692 			rdma_req->rsp.wr.imm_data = desc->keyed.key;
1693 		}
1694 	}
1695 #endif
1696 
1697 	rdma_req->num_outstanding_data_wr = num_sgl_descriptors;
1698 
1699 	return 0;
1700 
1701 err_exit:
1702 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1703 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1704 	return rc;
1705 }
1706 
1707 static int
1708 nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1709 			    struct spdk_nvmf_rdma_device *device,
1710 			    struct spdk_nvmf_rdma_request *rdma_req)
1711 {
1712 	struct spdk_nvmf_request		*req = &rdma_req->req;
1713 	struct spdk_nvme_cpl			*rsp;
1714 	struct spdk_nvme_sgl_descriptor		*sgl;
1715 	int					rc;
1716 	uint32_t				length;
1717 
1718 	rsp = &req->rsp->nvme_cpl;
1719 	sgl = &req->cmd->nvme_cmd.dptr.sgl1;
1720 
1721 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1722 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1723 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1724 
1725 		length = sgl->keyed.length;
1726 		if (length > rtransport->transport.opts.max_io_size) {
1727 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1728 				    length, rtransport->transport.opts.max_io_size);
1729 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1730 			return -1;
1731 		}
1732 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1733 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1734 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1735 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1736 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1737 			}
1738 		}
1739 #endif
1740 
1741 		/* fill request length and populate iovs */
1742 		req->length = length;
1743 
1744 		if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1745 			req->dif.orig_length = length;
1746 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
1747 			req->dif.elba_length = length;
1748 		}
1749 
1750 		rc = nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req, length);
1751 		if (spdk_unlikely(rc < 0)) {
1752 			if (rc == -EINVAL) {
1753 				SPDK_ERRLOG("SGL length exceeds the max I/O size\n");
1754 				rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1755 				return -1;
1756 			}
1757 			/* No available buffers. Queue this request up. */
1758 			SPDK_DEBUGLOG(rdma, "No available large data buffers. Queueing request %p\n", rdma_req);
1759 			return 0;
1760 		}
1761 
1762 		/* backward compatible */
1763 		req->data = req->iov[0].iov_base;
1764 
1765 		SPDK_DEBUGLOG(rdma, "Request %p took %d buffer/s from central pool\n", rdma_req,
1766 			      req->iovcnt);
1767 
1768 		return 0;
1769 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1770 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1771 		uint64_t offset = sgl->address;
1772 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1773 
1774 		SPDK_DEBUGLOG(nvmf, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1775 			      offset, sgl->unkeyed.length);
1776 
1777 		if (offset > max_len) {
1778 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1779 				    offset, max_len);
1780 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1781 			return -1;
1782 		}
1783 		max_len -= (uint32_t)offset;
1784 
1785 		if (sgl->unkeyed.length > max_len) {
1786 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1787 				    sgl->unkeyed.length, max_len);
1788 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1789 			return -1;
1790 		}
1791 
1792 		rdma_req->num_outstanding_data_wr = 0;
1793 		req->data = rdma_req->recv->buf + offset;
1794 		req->data_from_pool = false;
1795 		req->length = sgl->unkeyed.length;
1796 
1797 		req->iov[0].iov_base = req->data;
1798 		req->iov[0].iov_len = req->length;
1799 		req->iovcnt = 1;
1800 
1801 		return 0;
1802 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT &&
1803 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1804 
1805 		rc = nvmf_rdma_request_fill_iovs_multi_sgl(rtransport, device, rdma_req);
1806 		if (rc == -ENOMEM) {
1807 			SPDK_DEBUGLOG(rdma, "No available large data buffers. Queueing request %p\n", rdma_req);
1808 			return 0;
1809 		} else if (rc == -EINVAL) {
1810 			SPDK_ERRLOG("Multi SGL element request length exceeds the max I/O size\n");
1811 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1812 			return -1;
1813 		}
1814 
1815 		/* backward compatible */
1816 		req->data = req->iov[0].iov_base;
1817 
1818 		SPDK_DEBUGLOG(rdma, "Request %p took %d buffer/s from central pool\n", rdma_req,
1819 			      req->iovcnt);
1820 
1821 		return 0;
1822 	}
1823 
1824 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1825 		    sgl->generic.type, sgl->generic.subtype);
1826 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1827 	return -1;
1828 }
1829 
1830 static void
1831 _nvmf_rdma_request_free(struct spdk_nvmf_rdma_request *rdma_req,
1832 			struct spdk_nvmf_rdma_transport	*rtransport)
1833 {
1834 	struct spdk_nvmf_rdma_qpair		*rqpair;
1835 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1836 
1837 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1838 	if (rdma_req->req.data_from_pool) {
1839 		rgroup = rqpair->poller->group;
1840 
1841 		spdk_nvmf_request_free_buffers(&rdma_req->req, &rgroup->group, &rtransport->transport);
1842 	}
1843 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1844 	rdma_req->req.length = 0;
1845 	rdma_req->req.iovcnt = 0;
1846 	rdma_req->req.data = NULL;
1847 	rdma_req->rsp.wr.next = NULL;
1848 	rdma_req->data.wr.next = NULL;
1849 	memset(&rdma_req->req.dif, 0, sizeof(rdma_req->req.dif));
1850 	rqpair->qd--;
1851 
1852 	STAILQ_INSERT_HEAD(&rqpair->resources->free_queue, rdma_req, state_link);
1853 	rdma_req->state = RDMA_REQUEST_STATE_FREE;
1854 }
1855 
1856 bool
1857 nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
1858 			  struct spdk_nvmf_rdma_request *rdma_req)
1859 {
1860 	struct spdk_nvmf_rdma_qpair	*rqpair;
1861 	struct spdk_nvmf_rdma_device	*device;
1862 	struct spdk_nvmf_rdma_poll_group *rgroup;
1863 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
1864 	int				rc;
1865 	struct spdk_nvmf_rdma_recv	*rdma_recv;
1866 	enum spdk_nvmf_rdma_request_state prev_state;
1867 	bool				progress = false;
1868 	int				data_posted;
1869 	uint32_t			num_blocks;
1870 
1871 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1872 	device = rqpair->device;
1873 	rgroup = rqpair->poller->group;
1874 
1875 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
1876 
1877 	/* If the queue pair is in an error state, force the request to the completed state
1878 	 * to release resources. */
1879 	if (rqpair->ibv_state == IBV_QPS_ERR || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1880 		if (rdma_req->state == RDMA_REQUEST_STATE_NEED_BUFFER) {
1881 			STAILQ_REMOVE(&rgroup->group.pending_buf_queue, &rdma_req->req, spdk_nvmf_request, buf_link);
1882 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING) {
1883 			STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1884 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING) {
1885 			STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1886 		}
1887 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1888 	}
1889 
1890 	/* The loop here is to allow for several back-to-back state changes. */
1891 	do {
1892 		prev_state = rdma_req->state;
1893 
1894 		SPDK_DEBUGLOG(rdma, "Request %p entering state %d\n", rdma_req, prev_state);
1895 
1896 		switch (rdma_req->state) {
1897 		case RDMA_REQUEST_STATE_FREE:
1898 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
1899 			 * to escape this state. */
1900 			break;
1901 		case RDMA_REQUEST_STATE_NEW:
1902 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
1903 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1904 			rdma_recv = rdma_req->recv;
1905 
1906 			/* The first element of the SGL is the NVMe command */
1907 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
1908 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
1909 
1910 			if (rqpair->ibv_state == IBV_QPS_ERR  || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1911 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1912 				break;
1913 			}
1914 
1915 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&rdma_req->req, &rdma_req->req.dif.dif_ctx))) {
1916 				rdma_req->req.dif.dif_insert_or_strip = true;
1917 			}
1918 
1919 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1920 			rdma_req->rsp.wr.opcode = IBV_WR_SEND;
1921 			rdma_req->rsp.wr.imm_data = 0;
1922 #endif
1923 
1924 			/* The next state transition depends on the data transfer needs of this request. */
1925 			rdma_req->req.xfer = spdk_nvmf_req_get_xfer(&rdma_req->req);
1926 
1927 			if (spdk_unlikely(rdma_req->req.xfer == SPDK_NVME_DATA_BIDIRECTIONAL)) {
1928 				rsp->status.sct = SPDK_NVME_SCT_GENERIC;
1929 				rsp->status.sc = SPDK_NVME_SC_INVALID_OPCODE;
1930 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1931 				SPDK_DEBUGLOG(rdma, "Request %p: invalid xfer type (BIDIRECTIONAL)\n", rdma_req);
1932 				break;
1933 			}
1934 
1935 			/* If no data to transfer, ready to execute. */
1936 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
1937 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1938 				break;
1939 			}
1940 
1941 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
1942 			STAILQ_INSERT_TAIL(&rgroup->group.pending_buf_queue, &rdma_req->req, buf_link);
1943 			break;
1944 		case RDMA_REQUEST_STATE_NEED_BUFFER:
1945 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
1946 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1947 
1948 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
1949 
1950 			if (&rdma_req->req != STAILQ_FIRST(&rgroup->group.pending_buf_queue)) {
1951 				/* This request needs to wait in line to obtain a buffer */
1952 				break;
1953 			}
1954 
1955 			/* Try to get a data buffer */
1956 			rc = nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
1957 			if (rc < 0) {
1958 				STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
1959 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1960 				break;
1961 			}
1962 
1963 			if (!rdma_req->req.data) {
1964 				/* No buffers available. */
1965 				rgroup->stat.pending_data_buffer++;
1966 				break;
1967 			}
1968 
1969 			STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
1970 
1971 			/* If data is transferring from host to controller and the data didn't
1972 			 * arrive using in capsule data, we need to do a transfer from the host.
1973 			 */
1974 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER &&
1975 			    rdma_req->req.data_from_pool) {
1976 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
1977 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
1978 				break;
1979 			}
1980 
1981 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1982 			break;
1983 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
1984 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING, 0, 0,
1985 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1986 
1987 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_read_queue)) {
1988 				/* This request needs to wait in line to perform RDMA */
1989 				break;
1990 			}
1991 			if (rqpair->current_send_depth + rdma_req->num_outstanding_data_wr > rqpair->max_send_depth
1992 			    || rqpair->current_read_depth + rdma_req->num_outstanding_data_wr > rqpair->max_read_depth) {
1993 				/* We can only have so many WRs outstanding. we have to wait until some finish. */
1994 				rqpair->poller->stat.pending_rdma_read++;
1995 				break;
1996 			}
1997 
1998 			/* We have already verified that this request is the head of the queue. */
1999 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_read_queue, state_link);
2000 
2001 			rc = request_transfer_in(&rdma_req->req);
2002 			if (!rc) {
2003 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
2004 			} else {
2005 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
2006 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2007 			}
2008 			break;
2009 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2010 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2011 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2012 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
2013 			 * to escape this state. */
2014 			break;
2015 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
2016 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
2017 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2018 
2019 			if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
2020 				if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2021 					/* generate DIF for write operation */
2022 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2023 					assert(num_blocks > 0);
2024 
2025 					rc = spdk_dif_generate(rdma_req->req.iov, rdma_req->req.iovcnt,
2026 							       num_blocks, &rdma_req->req.dif.dif_ctx);
2027 					if (rc != 0) {
2028 						SPDK_ERRLOG("DIF generation failed\n");
2029 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2030 						spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2031 						break;
2032 					}
2033 				}
2034 
2035 				assert(rdma_req->req.dif.elba_length >= rdma_req->req.length);
2036 				/* set extended length before IO operation */
2037 				rdma_req->req.length = rdma_req->req.dif.elba_length;
2038 			}
2039 
2040 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
2041 			spdk_nvmf_request_exec(&rdma_req->req);
2042 			break;
2043 		case RDMA_REQUEST_STATE_EXECUTING:
2044 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
2045 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2046 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
2047 			 * to escape this state. */
2048 			break;
2049 		case RDMA_REQUEST_STATE_EXECUTED:
2050 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
2051 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2052 			if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
2053 			    rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2054 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_write_queue, rdma_req, state_link);
2055 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING;
2056 			} else {
2057 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2058 			}
2059 			if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
2060 				/* restore the original length */
2061 				rdma_req->req.length = rdma_req->req.dif.orig_length;
2062 
2063 				if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2064 					struct spdk_dif_error error_blk;
2065 
2066 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2067 
2068 					rc = spdk_dif_verify(rdma_req->req.iov, rdma_req->req.iovcnt, num_blocks,
2069 							     &rdma_req->req.dif.dif_ctx, &error_blk);
2070 					if (rc) {
2071 						struct spdk_nvme_cpl *rsp = &rdma_req->req.rsp->nvme_cpl;
2072 
2073 						SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n", error_blk.err_type,
2074 							    error_blk.err_offset);
2075 						rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2076 						rsp->status.sc = nvmf_rdma_dif_error_to_compl_status(error_blk.err_type);
2077 						rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2078 						STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2079 					}
2080 				}
2081 			}
2082 			break;
2083 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
2084 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING, 0, 0,
2085 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2086 
2087 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_write_queue)) {
2088 				/* This request needs to wait in line to perform RDMA */
2089 				break;
2090 			}
2091 			if ((rqpair->current_send_depth + rdma_req->num_outstanding_data_wr + 1) >
2092 			    rqpair->max_send_depth) {
2093 				/* We can only have so many WRs outstanding. we have to wait until some finish.
2094 				 * +1 since each request has an additional wr in the resp. */
2095 				rqpair->poller->stat.pending_rdma_write++;
2096 				break;
2097 			}
2098 
2099 			/* We have already verified that this request is the head of the queue. */
2100 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_write_queue, state_link);
2101 
2102 			/* The data transfer will be kicked off from
2103 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
2104 			 */
2105 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2106 			break;
2107 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
2108 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
2109 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2110 			rc = request_transfer_out(&rdma_req->req, &data_posted);
2111 			assert(rc == 0); /* No good way to handle this currently */
2112 			if (rc) {
2113 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2114 			} else {
2115 				rdma_req->state = data_posted ? RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
2116 						  RDMA_REQUEST_STATE_COMPLETING;
2117 			}
2118 			break;
2119 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2120 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2121 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2122 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2123 			 * to escape this state. */
2124 			break;
2125 		case RDMA_REQUEST_STATE_COMPLETING:
2126 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
2127 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2128 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2129 			 * to escape this state. */
2130 			break;
2131 		case RDMA_REQUEST_STATE_COMPLETED:
2132 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
2133 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2134 
2135 			rqpair->poller->stat.request_latency += spdk_get_ticks() - rdma_req->receive_tsc;
2136 			_nvmf_rdma_request_free(rdma_req, rtransport);
2137 			break;
2138 		case RDMA_REQUEST_NUM_STATES:
2139 		default:
2140 			assert(0);
2141 			break;
2142 		}
2143 
2144 		if (rdma_req->state != prev_state) {
2145 			progress = true;
2146 		}
2147 	} while (rdma_req->state != prev_state);
2148 
2149 	return progress;
2150 }
2151 
2152 /* Public API callbacks begin here */
2153 
2154 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
2155 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
2156 #define SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH 4096
2157 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
2158 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2159 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
2160 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
2161 #define SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS 4095
2162 #define SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE 32
2163 #define SPDK_NVMF_RDMA_DEFAULT_NO_SRQ false
2164 #define SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP false
2165 #define SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG 100
2166 #define SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC 1
2167 #define SPDK_NVMF_RDMA_DEFAULT_NO_WR_BATCHING false
2168 
2169 static void
2170 nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
2171 {
2172 	opts->max_queue_depth =		SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
2173 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2174 	opts->in_capsule_data_size =	SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
2175 	opts->max_io_size =		SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
2176 	opts->io_unit_size =		SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE;
2177 	opts->max_aq_depth =		SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
2178 	opts->num_shared_buffers =	SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS;
2179 	opts->buf_cache_size =		SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE;
2180 	opts->dif_insert_or_strip =	SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP;
2181 	opts->abort_timeout_sec =	SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC;
2182 	opts->transport_specific =      NULL;
2183 }
2184 
2185 static int nvmf_rdma_destroy(struct spdk_nvmf_transport *transport,
2186 			     spdk_nvmf_transport_destroy_done_cb cb_fn, void *cb_arg);
2187 
2188 static inline bool
2189 nvmf_rdma_is_rxe_device(struct spdk_nvmf_rdma_device *device)
2190 {
2191 	return device->attr.vendor_id == NVMF_RXE_VENDOR_ID_OLD ||
2192 	       device->attr.vendor_id == NVMF_RXE_VENDOR_ID_NEW;
2193 }
2194 
2195 static struct spdk_nvmf_transport *
2196 nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
2197 {
2198 	int rc;
2199 	struct spdk_nvmf_rdma_transport *rtransport;
2200 	struct spdk_nvmf_rdma_device	*device, *tmp;
2201 	struct ibv_context		**contexts;
2202 	uint32_t			i;
2203 	int				flag;
2204 	uint32_t			sge_count;
2205 	uint32_t			min_shared_buffers;
2206 	int				max_device_sge = SPDK_NVMF_MAX_SGL_ENTRIES;
2207 	pthread_mutexattr_t		attr;
2208 
2209 	rtransport = calloc(1, sizeof(*rtransport));
2210 	if (!rtransport) {
2211 		return NULL;
2212 	}
2213 
2214 	if (pthread_mutexattr_init(&attr)) {
2215 		SPDK_ERRLOG("pthread_mutexattr_init() failed\n");
2216 		free(rtransport);
2217 		return NULL;
2218 	}
2219 
2220 	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) {
2221 		SPDK_ERRLOG("pthread_mutexattr_settype() failed\n");
2222 		pthread_mutexattr_destroy(&attr);
2223 		free(rtransport);
2224 		return NULL;
2225 	}
2226 
2227 	if (pthread_mutex_init(&rtransport->lock, &attr)) {
2228 		SPDK_ERRLOG("pthread_mutex_init() failed\n");
2229 		pthread_mutexattr_destroy(&attr);
2230 		free(rtransport);
2231 		return NULL;
2232 	}
2233 
2234 	pthread_mutexattr_destroy(&attr);
2235 
2236 	TAILQ_INIT(&rtransport->devices);
2237 	TAILQ_INIT(&rtransport->ports);
2238 	TAILQ_INIT(&rtransport->poll_groups);
2239 
2240 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
2241 	rtransport->rdma_opts.max_srq_depth = SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH;
2242 	rtransport->rdma_opts.no_srq = SPDK_NVMF_RDMA_DEFAULT_NO_SRQ;
2243 	rtransport->rdma_opts.acceptor_backlog = SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2244 	rtransport->rdma_opts.no_wr_batching = SPDK_NVMF_RDMA_DEFAULT_NO_WR_BATCHING;
2245 	if (opts->transport_specific != NULL &&
2246 	    spdk_json_decode_object_relaxed(opts->transport_specific, rdma_transport_opts_decoder,
2247 					    SPDK_COUNTOF(rdma_transport_opts_decoder),
2248 					    &rtransport->rdma_opts)) {
2249 		SPDK_ERRLOG("spdk_json_decode_object_relaxed failed\n");
2250 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2251 		return NULL;
2252 	}
2253 
2254 	SPDK_INFOLOG(rdma, "*** RDMA Transport Init ***\n"
2255 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
2256 		     "  max_io_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
2257 		     "  in_capsule_data_size=%d, max_aq_depth=%d,\n"
2258 		     "  num_shared_buffers=%d, max_srq_depth=%d, no_srq=%d,"
2259 		     "  acceptor_backlog=%d, no_wr_batching=%d abort_timeout_sec=%d\n",
2260 		     opts->max_queue_depth,
2261 		     opts->max_io_size,
2262 		     opts->max_qpairs_per_ctrlr - 1,
2263 		     opts->io_unit_size,
2264 		     opts->in_capsule_data_size,
2265 		     opts->max_aq_depth,
2266 		     opts->num_shared_buffers,
2267 		     rtransport->rdma_opts.max_srq_depth,
2268 		     rtransport->rdma_opts.no_srq,
2269 		     rtransport->rdma_opts.acceptor_backlog,
2270 		     rtransport->rdma_opts.no_wr_batching,
2271 		     opts->abort_timeout_sec);
2272 
2273 	/* I/O unit size cannot be larger than max I/O size */
2274 	if (opts->io_unit_size > opts->max_io_size) {
2275 		opts->io_unit_size = opts->max_io_size;
2276 	}
2277 
2278 	if (rtransport->rdma_opts.acceptor_backlog <= 0) {
2279 		SPDK_ERRLOG("The acceptor backlog cannot be less than 1, setting to the default value of (%d).\n",
2280 			    SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG);
2281 		rtransport->rdma_opts.acceptor_backlog = SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2282 	}
2283 
2284 	if (opts->num_shared_buffers < (SPDK_NVMF_MAX_SGL_ENTRIES * 2)) {
2285 		SPDK_ERRLOG("The number of shared data buffers (%d) is less than"
2286 			    "the minimum number required to guarantee that forward progress can be made (%d)\n",
2287 			    opts->num_shared_buffers, (SPDK_NVMF_MAX_SGL_ENTRIES * 2));
2288 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2289 		return NULL;
2290 	}
2291 
2292 	min_shared_buffers = spdk_env_get_core_count() * opts->buf_cache_size;
2293 	if (min_shared_buffers > opts->num_shared_buffers) {
2294 		SPDK_ERRLOG("There are not enough buffers to satisfy"
2295 			    "per-poll group caches for each thread. (%" PRIu32 ")"
2296 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
2297 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
2298 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2299 		return NULL;
2300 	}
2301 
2302 	sge_count = opts->max_io_size / opts->io_unit_size;
2303 	if (sge_count > NVMF_DEFAULT_TX_SGE) {
2304 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
2305 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2306 		return NULL;
2307 	}
2308 
2309 	rtransport->event_channel = rdma_create_event_channel();
2310 	if (rtransport->event_channel == NULL) {
2311 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
2312 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2313 		return NULL;
2314 	}
2315 
2316 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
2317 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2318 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
2319 			    rtransport->event_channel->fd, spdk_strerror(errno));
2320 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2321 		return NULL;
2322 	}
2323 
2324 	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data",
2325 				   opts->max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES,
2326 				   sizeof(struct spdk_nvmf_rdma_request_data),
2327 				   SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
2328 				   SPDK_ENV_SOCKET_ID_ANY);
2329 	if (!rtransport->data_wr_pool) {
2330 		SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");
2331 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2332 		return NULL;
2333 	}
2334 
2335 	contexts = rdma_get_devices(NULL);
2336 	if (contexts == NULL) {
2337 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2338 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2339 		return NULL;
2340 	}
2341 
2342 	i = 0;
2343 	rc = 0;
2344 	while (contexts[i] != NULL) {
2345 		device = calloc(1, sizeof(*device));
2346 		if (!device) {
2347 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
2348 			rc = -ENOMEM;
2349 			break;
2350 		}
2351 		device->context = contexts[i];
2352 		rc = ibv_query_device(device->context, &device->attr);
2353 		if (rc < 0) {
2354 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2355 			free(device);
2356 			break;
2357 
2358 		}
2359 
2360 		max_device_sge = spdk_min(max_device_sge, device->attr.max_sge);
2361 
2362 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2363 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
2364 			SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
2365 			SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
2366 		}
2367 
2368 		/**
2369 		 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
2370 		 * The Soft-RoCE RXE driver does not currently support send with invalidate,
2371 		 * but incorrectly reports that it does. There are changes making their way
2372 		 * through the kernel now that will enable this feature. When they are merged,
2373 		 * we can conditionally enable this feature.
2374 		 *
2375 		 * TODO: enable this for versions of the kernel rxe driver that support it.
2376 		 */
2377 		if (nvmf_rdma_is_rxe_device(device)) {
2378 			device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
2379 		}
2380 #endif
2381 
2382 		/* set up device context async ev fd as NON_BLOCKING */
2383 		flag = fcntl(device->context->async_fd, F_GETFL);
2384 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
2385 		if (rc < 0) {
2386 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
2387 			free(device);
2388 			break;
2389 		}
2390 
2391 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
2392 		i++;
2393 
2394 		if (g_nvmf_hooks.get_ibv_pd) {
2395 			device->pd = g_nvmf_hooks.get_ibv_pd(NULL, device->context);
2396 		} else {
2397 			device->pd = ibv_alloc_pd(device->context);
2398 		}
2399 
2400 		if (!device->pd) {
2401 			SPDK_ERRLOG("Unable to allocate protection domain.\n");
2402 			rc = -ENOMEM;
2403 			break;
2404 		}
2405 
2406 		assert(device->map == NULL);
2407 
2408 		device->map = spdk_rdma_create_mem_map(device->pd, &g_nvmf_hooks);
2409 		if (!device->map) {
2410 			SPDK_ERRLOG("Unable to allocate memory map for listen address\n");
2411 			rc = -ENOMEM;
2412 			break;
2413 		}
2414 
2415 		assert(device->map != NULL);
2416 		assert(device->pd != NULL);
2417 	}
2418 	rdma_free_devices(contexts);
2419 
2420 	if (opts->io_unit_size * max_device_sge < opts->max_io_size) {
2421 		/* divide and round up. */
2422 		opts->io_unit_size = (opts->max_io_size + max_device_sge - 1) / max_device_sge;
2423 
2424 		/* round up to the nearest 4k. */
2425 		opts->io_unit_size = (opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT - 1) & ~NVMF_DATA_BUFFER_MASK;
2426 
2427 		opts->io_unit_size = spdk_max(opts->io_unit_size, SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
2428 		SPDK_NOTICELOG("Adjusting the io unit size to fit the device's maximum I/O size. New I/O unit size %u\n",
2429 			       opts->io_unit_size);
2430 	}
2431 
2432 	if (rc < 0) {
2433 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2434 		return NULL;
2435 	}
2436 
2437 	/* Set up poll descriptor array to monitor events from RDMA and IB
2438 	 * in a single poll syscall
2439 	 */
2440 	rtransport->npoll_fds = i + 1;
2441 	i = 0;
2442 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
2443 	if (rtransport->poll_fds == NULL) {
2444 		SPDK_ERRLOG("poll_fds allocation failed\n");
2445 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2446 		return NULL;
2447 	}
2448 
2449 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
2450 	rtransport->poll_fds[i++].events = POLLIN;
2451 
2452 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2453 		rtransport->poll_fds[i].fd = device->context->async_fd;
2454 		rtransport->poll_fds[i++].events = POLLIN;
2455 	}
2456 
2457 	return &rtransport->transport;
2458 }
2459 
2460 static void
2461 nvmf_rdma_dump_opts(struct spdk_nvmf_transport *transport, struct spdk_json_write_ctx *w)
2462 {
2463 	struct spdk_nvmf_rdma_transport	*rtransport;
2464 	assert(w != NULL);
2465 
2466 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2467 	spdk_json_write_named_uint32(w, "max_srq_depth", rtransport->rdma_opts.max_srq_depth);
2468 	spdk_json_write_named_bool(w, "no_srq", rtransport->rdma_opts.no_srq);
2469 	spdk_json_write_named_int32(w, "acceptor_backlog", rtransport->rdma_opts.acceptor_backlog);
2470 	spdk_json_write_named_bool(w, "no_wr_batching", rtransport->rdma_opts.no_wr_batching);
2471 }
2472 
2473 static int
2474 nvmf_rdma_destroy(struct spdk_nvmf_transport *transport,
2475 		  spdk_nvmf_transport_destroy_done_cb cb_fn, void *cb_arg)
2476 {
2477 	struct spdk_nvmf_rdma_transport	*rtransport;
2478 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
2479 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
2480 
2481 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2482 
2483 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
2484 		TAILQ_REMOVE(&rtransport->ports, port, link);
2485 		rdma_destroy_id(port->id);
2486 		free(port);
2487 	}
2488 
2489 	if (rtransport->poll_fds != NULL) {
2490 		free(rtransport->poll_fds);
2491 	}
2492 
2493 	if (rtransport->event_channel != NULL) {
2494 		rdma_destroy_event_channel(rtransport->event_channel);
2495 	}
2496 
2497 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
2498 		TAILQ_REMOVE(&rtransport->devices, device, link);
2499 		spdk_rdma_free_mem_map(&device->map);
2500 		if (device->pd) {
2501 			if (!g_nvmf_hooks.get_ibv_pd) {
2502 				ibv_dealloc_pd(device->pd);
2503 			}
2504 		}
2505 		free(device);
2506 	}
2507 
2508 	if (rtransport->data_wr_pool != NULL) {
2509 		if (spdk_mempool_count(rtransport->data_wr_pool) !=
2510 		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {
2511 			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",
2512 				    spdk_mempool_count(rtransport->data_wr_pool),
2513 				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);
2514 		}
2515 	}
2516 
2517 	spdk_mempool_free(rtransport->data_wr_pool);
2518 
2519 	pthread_mutex_destroy(&rtransport->lock);
2520 	free(rtransport);
2521 
2522 	if (cb_fn) {
2523 		cb_fn(cb_arg);
2524 	}
2525 	return 0;
2526 }
2527 
2528 static int
2529 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2530 			  struct spdk_nvme_transport_id *trid,
2531 			  bool peer);
2532 
2533 static int
2534 nvmf_rdma_listen(struct spdk_nvmf_transport *transport, const struct spdk_nvme_transport_id *trid,
2535 		 struct spdk_nvmf_listen_opts *listen_opts)
2536 {
2537 	struct spdk_nvmf_rdma_transport	*rtransport;
2538 	struct spdk_nvmf_rdma_device	*device;
2539 	struct spdk_nvmf_rdma_port	*port;
2540 	struct addrinfo			*res;
2541 	struct addrinfo			hints;
2542 	int				family;
2543 	int				rc;
2544 
2545 	if (!strlen(trid->trsvcid)) {
2546 		SPDK_ERRLOG("Service id is required\n");
2547 		return -EINVAL;
2548 	}
2549 
2550 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2551 	assert(rtransport->event_channel != NULL);
2552 
2553 	pthread_mutex_lock(&rtransport->lock);
2554 	port = calloc(1, sizeof(*port));
2555 	if (!port) {
2556 		SPDK_ERRLOG("Port allocation failed\n");
2557 		pthread_mutex_unlock(&rtransport->lock);
2558 		return -ENOMEM;
2559 	}
2560 
2561 	port->trid = trid;
2562 
2563 	switch (trid->adrfam) {
2564 	case SPDK_NVMF_ADRFAM_IPV4:
2565 		family = AF_INET;
2566 		break;
2567 	case SPDK_NVMF_ADRFAM_IPV6:
2568 		family = AF_INET6;
2569 		break;
2570 	default:
2571 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", trid->adrfam);
2572 		free(port);
2573 		pthread_mutex_unlock(&rtransport->lock);
2574 		return -EINVAL;
2575 	}
2576 
2577 	memset(&hints, 0, sizeof(hints));
2578 	hints.ai_family = family;
2579 	hints.ai_flags = AI_NUMERICSERV;
2580 	hints.ai_socktype = SOCK_STREAM;
2581 	hints.ai_protocol = 0;
2582 
2583 	rc = getaddrinfo(trid->traddr, trid->trsvcid, &hints, &res);
2584 	if (rc) {
2585 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
2586 		free(port);
2587 		pthread_mutex_unlock(&rtransport->lock);
2588 		return -EINVAL;
2589 	}
2590 
2591 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
2592 	if (rc < 0) {
2593 		SPDK_ERRLOG("rdma_create_id() failed\n");
2594 		freeaddrinfo(res);
2595 		free(port);
2596 		pthread_mutex_unlock(&rtransport->lock);
2597 		return rc;
2598 	}
2599 
2600 	rc = rdma_bind_addr(port->id, res->ai_addr);
2601 	freeaddrinfo(res);
2602 
2603 	if (rc < 0) {
2604 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
2605 		rdma_destroy_id(port->id);
2606 		free(port);
2607 		pthread_mutex_unlock(&rtransport->lock);
2608 		return rc;
2609 	}
2610 
2611 	if (!port->id->verbs) {
2612 		SPDK_ERRLOG("ibv_context is null\n");
2613 		rdma_destroy_id(port->id);
2614 		free(port);
2615 		pthread_mutex_unlock(&rtransport->lock);
2616 		return -1;
2617 	}
2618 
2619 	rc = rdma_listen(port->id, rtransport->rdma_opts.acceptor_backlog);
2620 	if (rc < 0) {
2621 		SPDK_ERRLOG("rdma_listen() failed\n");
2622 		rdma_destroy_id(port->id);
2623 		free(port);
2624 		pthread_mutex_unlock(&rtransport->lock);
2625 		return rc;
2626 	}
2627 
2628 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2629 		if (device->context == port->id->verbs) {
2630 			port->device = device;
2631 			break;
2632 		}
2633 	}
2634 	if (!port->device) {
2635 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
2636 			    port->id->verbs);
2637 		rdma_destroy_id(port->id);
2638 		free(port);
2639 		pthread_mutex_unlock(&rtransport->lock);
2640 		return -EINVAL;
2641 	}
2642 
2643 	SPDK_NOTICELOG("*** NVMe/RDMA Target Listening on %s port %s ***\n",
2644 		       trid->traddr, trid->trsvcid);
2645 
2646 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
2647 	pthread_mutex_unlock(&rtransport->lock);
2648 	return 0;
2649 }
2650 
2651 static void
2652 nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
2653 		      const struct spdk_nvme_transport_id *trid)
2654 {
2655 	struct spdk_nvmf_rdma_transport *rtransport;
2656 	struct spdk_nvmf_rdma_port *port, *tmp;
2657 
2658 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2659 
2660 	pthread_mutex_lock(&rtransport->lock);
2661 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
2662 		if (spdk_nvme_transport_id_compare(port->trid, trid) == 0) {
2663 			TAILQ_REMOVE(&rtransport->ports, port, link);
2664 			rdma_destroy_id(port->id);
2665 			free(port);
2666 			break;
2667 		}
2668 	}
2669 
2670 	pthread_mutex_unlock(&rtransport->lock);
2671 }
2672 
2673 static void
2674 nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
2675 				struct spdk_nvmf_rdma_qpair *rqpair, bool drain)
2676 {
2677 	struct spdk_nvmf_request *req, *tmp;
2678 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
2679 	struct spdk_nvmf_rdma_resources *resources;
2680 
2681 	/* We process I/O in the data transfer pending queue at the highest priority. RDMA reads first */
2682 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_read_queue, state_link, req_tmp) {
2683 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2684 			break;
2685 		}
2686 	}
2687 
2688 	/* Then RDMA writes since reads have stronger restrictions than writes */
2689 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_write_queue, state_link, req_tmp) {
2690 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2691 			break;
2692 		}
2693 	}
2694 
2695 	/* Then we handle request waiting on memory buffers. */
2696 	STAILQ_FOREACH_SAFE(req, &rqpair->poller->group->group.pending_buf_queue, buf_link, tmp) {
2697 		rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
2698 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2699 			break;
2700 		}
2701 	}
2702 
2703 	resources = rqpair->resources;
2704 	while (!STAILQ_EMPTY(&resources->free_queue) && !STAILQ_EMPTY(&resources->incoming_queue)) {
2705 		rdma_req = STAILQ_FIRST(&resources->free_queue);
2706 		STAILQ_REMOVE_HEAD(&resources->free_queue, state_link);
2707 		rdma_req->recv = STAILQ_FIRST(&resources->incoming_queue);
2708 		STAILQ_REMOVE_HEAD(&resources->incoming_queue, link);
2709 
2710 		if (rqpair->srq != NULL) {
2711 			rdma_req->req.qpair = &rdma_req->recv->qpair->qpair;
2712 			rdma_req->recv->qpair->qd++;
2713 		} else {
2714 			rqpair->qd++;
2715 		}
2716 
2717 		rdma_req->receive_tsc = rdma_req->recv->receive_tsc;
2718 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
2719 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false) {
2720 			break;
2721 		}
2722 	}
2723 	if (!STAILQ_EMPTY(&resources->incoming_queue) && STAILQ_EMPTY(&resources->free_queue)) {
2724 		rqpair->poller->stat.pending_free_request++;
2725 	}
2726 }
2727 
2728 static inline bool
2729 nvmf_rdma_can_ignore_last_wqe_reached(struct spdk_nvmf_rdma_device *device)
2730 {
2731 	/* iWARP transport and SoftRoCE driver don't support LAST_WQE_REACHED ibv async event */
2732 	return nvmf_rdma_is_rxe_device(device) ||
2733 	       device->context->device->transport_type == IBV_TRANSPORT_IWARP;
2734 }
2735 
2736 static void
2737 nvmf_rdma_destroy_drained_qpair(struct spdk_nvmf_rdma_qpair *rqpair)
2738 {
2739 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
2740 			struct spdk_nvmf_rdma_transport, transport);
2741 
2742 	nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
2743 
2744 	/* nvmr_rdma_close_qpair is not called */
2745 	if (!rqpair->to_close) {
2746 		return;
2747 	}
2748 
2749 	/* In non SRQ path, we will reach rqpair->max_queue_depth. In SRQ path, we will get the last_wqe event. */
2750 	if (rqpair->current_send_depth != 0) {
2751 		return;
2752 	}
2753 
2754 	if (rqpair->srq == NULL && rqpair->current_recv_depth != rqpair->max_queue_depth) {
2755 		return;
2756 	}
2757 
2758 	if (rqpair->srq != NULL && rqpair->last_wqe_reached == false &&
2759 	    !nvmf_rdma_can_ignore_last_wqe_reached(rqpair->device)) {
2760 		return;
2761 	}
2762 
2763 	assert(rqpair->qpair.state == SPDK_NVMF_QPAIR_ERROR);
2764 
2765 	nvmf_rdma_qpair_destroy(rqpair);
2766 }
2767 
2768 static int
2769 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
2770 {
2771 	struct spdk_nvmf_qpair		*qpair;
2772 	struct spdk_nvmf_rdma_qpair	*rqpair;
2773 
2774 	if (evt->id == NULL) {
2775 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
2776 		return -1;
2777 	}
2778 
2779 	qpair = evt->id->context;
2780 	if (qpair == NULL) {
2781 		SPDK_ERRLOG("disconnect request: no active connection\n");
2782 		return -1;
2783 	}
2784 
2785 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2786 
2787 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair->cm_id, 0);
2788 
2789 	spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2790 
2791 	return 0;
2792 }
2793 
2794 #ifdef DEBUG
2795 static const char *CM_EVENT_STR[] = {
2796 	"RDMA_CM_EVENT_ADDR_RESOLVED",
2797 	"RDMA_CM_EVENT_ADDR_ERROR",
2798 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
2799 	"RDMA_CM_EVENT_ROUTE_ERROR",
2800 	"RDMA_CM_EVENT_CONNECT_REQUEST",
2801 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
2802 	"RDMA_CM_EVENT_CONNECT_ERROR",
2803 	"RDMA_CM_EVENT_UNREACHABLE",
2804 	"RDMA_CM_EVENT_REJECTED",
2805 	"RDMA_CM_EVENT_ESTABLISHED",
2806 	"RDMA_CM_EVENT_DISCONNECTED",
2807 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
2808 	"RDMA_CM_EVENT_MULTICAST_JOIN",
2809 	"RDMA_CM_EVENT_MULTICAST_ERROR",
2810 	"RDMA_CM_EVENT_ADDR_CHANGE",
2811 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
2812 };
2813 #endif /* DEBUG */
2814 
2815 static void
2816 nvmf_rdma_disconnect_qpairs_on_port(struct spdk_nvmf_rdma_transport *rtransport,
2817 				    struct spdk_nvmf_rdma_port *port)
2818 {
2819 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2820 	struct spdk_nvmf_rdma_poller		*rpoller;
2821 	struct spdk_nvmf_rdma_qpair		*rqpair;
2822 
2823 	TAILQ_FOREACH(rgroup, &rtransport->poll_groups, link) {
2824 		TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
2825 			TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
2826 				if (rqpair->listen_id == port->id) {
2827 					spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2828 				}
2829 			}
2830 		}
2831 	}
2832 }
2833 
2834 static bool
2835 nvmf_rdma_handle_cm_event_addr_change(struct spdk_nvmf_transport *transport,
2836 				      struct rdma_cm_event *event)
2837 {
2838 	const struct spdk_nvme_transport_id	*trid;
2839 	struct spdk_nvmf_rdma_port		*port;
2840 	struct spdk_nvmf_rdma_transport		*rtransport;
2841 	bool					event_acked = false;
2842 
2843 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2844 	TAILQ_FOREACH(port, &rtransport->ports, link) {
2845 		if (port->id == event->id) {
2846 			SPDK_ERRLOG("ADDR_CHANGE: IP %s:%s migrated\n", port->trid->traddr, port->trid->trsvcid);
2847 			rdma_ack_cm_event(event);
2848 			event_acked = true;
2849 			trid = port->trid;
2850 			break;
2851 		}
2852 	}
2853 
2854 	if (event_acked) {
2855 		nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
2856 
2857 		nvmf_rdma_stop_listen(transport, trid);
2858 		nvmf_rdma_listen(transport, trid, NULL);
2859 	}
2860 
2861 	return event_acked;
2862 }
2863 
2864 static void
2865 nvmf_rdma_handle_cm_event_port_removal(struct spdk_nvmf_transport *transport,
2866 				       struct rdma_cm_event *event)
2867 {
2868 	struct spdk_nvmf_rdma_port		*port;
2869 	struct spdk_nvmf_rdma_transport		*rtransport;
2870 
2871 	port = event->id->context;
2872 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2873 
2874 	SPDK_NOTICELOG("Port %s:%s is being removed\n", port->trid->traddr, port->trid->trsvcid);
2875 
2876 	nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
2877 
2878 	rdma_ack_cm_event(event);
2879 
2880 	while (spdk_nvmf_transport_stop_listen(transport, port->trid) == 0) {
2881 		;
2882 	}
2883 }
2884 
2885 static void
2886 nvmf_process_cm_event(struct spdk_nvmf_transport *transport)
2887 {
2888 	struct spdk_nvmf_rdma_transport *rtransport;
2889 	struct rdma_cm_event		*event;
2890 	int				rc;
2891 	bool				event_acked;
2892 
2893 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2894 
2895 	if (rtransport->event_channel == NULL) {
2896 		return;
2897 	}
2898 
2899 	while (1) {
2900 		event_acked = false;
2901 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
2902 		if (rc) {
2903 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
2904 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
2905 			}
2906 			break;
2907 		}
2908 
2909 		SPDK_DEBUGLOG(rdma, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
2910 
2911 		spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
2912 
2913 		switch (event->event) {
2914 		case RDMA_CM_EVENT_ADDR_RESOLVED:
2915 		case RDMA_CM_EVENT_ADDR_ERROR:
2916 		case RDMA_CM_EVENT_ROUTE_RESOLVED:
2917 		case RDMA_CM_EVENT_ROUTE_ERROR:
2918 			/* No action required. The target never attempts to resolve routes. */
2919 			break;
2920 		case RDMA_CM_EVENT_CONNECT_REQUEST:
2921 			rc = nvmf_rdma_connect(transport, event);
2922 			if (rc < 0) {
2923 				SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
2924 				break;
2925 			}
2926 			break;
2927 		case RDMA_CM_EVENT_CONNECT_RESPONSE:
2928 			/* The target never initiates a new connection. So this will not occur. */
2929 			break;
2930 		case RDMA_CM_EVENT_CONNECT_ERROR:
2931 			/* Can this happen? The docs say it can, but not sure what causes it. */
2932 			break;
2933 		case RDMA_CM_EVENT_UNREACHABLE:
2934 		case RDMA_CM_EVENT_REJECTED:
2935 			/* These only occur on the client side. */
2936 			break;
2937 		case RDMA_CM_EVENT_ESTABLISHED:
2938 			/* TODO: Should we be waiting for this event anywhere? */
2939 			break;
2940 		case RDMA_CM_EVENT_DISCONNECTED:
2941 			rc = nvmf_rdma_disconnect(event);
2942 			if (rc < 0) {
2943 				SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2944 				break;
2945 			}
2946 			break;
2947 		case RDMA_CM_EVENT_DEVICE_REMOVAL:
2948 			/* In case of device removal, kernel IB part triggers IBV_EVENT_DEVICE_FATAL
2949 			 * which triggers RDMA_CM_EVENT_DEVICE_REMOVAL on all cma_id’s.
2950 			 * Once these events are sent to SPDK, we should release all IB resources and
2951 			 * don't make attempts to call any ibv_query/modify/create functions. We can only call
2952 			 * ibv_destory* functions to release user space memory allocated by IB. All kernel
2953 			 * resources are already cleaned. */
2954 			if (event->id->qp) {
2955 				/* If rdma_cm event has a valid `qp` pointer then the event refers to the
2956 				 * corresponding qpair. Otherwise the event refers to a listening device */
2957 				rc = nvmf_rdma_disconnect(event);
2958 				if (rc < 0) {
2959 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2960 					break;
2961 				}
2962 			} else {
2963 				nvmf_rdma_handle_cm_event_port_removal(transport, event);
2964 				event_acked = true;
2965 			}
2966 			break;
2967 		case RDMA_CM_EVENT_MULTICAST_JOIN:
2968 		case RDMA_CM_EVENT_MULTICAST_ERROR:
2969 			/* Multicast is not used */
2970 			break;
2971 		case RDMA_CM_EVENT_ADDR_CHANGE:
2972 			event_acked = nvmf_rdma_handle_cm_event_addr_change(transport, event);
2973 			break;
2974 		case RDMA_CM_EVENT_TIMEWAIT_EXIT:
2975 			/* For now, do nothing. The target never re-uses queue pairs. */
2976 			break;
2977 		default:
2978 			SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
2979 			break;
2980 		}
2981 		if (!event_acked) {
2982 			rdma_ack_cm_event(event);
2983 		}
2984 	}
2985 }
2986 
2987 static void
2988 nvmf_rdma_handle_last_wqe_reached(struct spdk_nvmf_rdma_qpair *rqpair)
2989 {
2990 	rqpair->last_wqe_reached = true;
2991 	nvmf_rdma_destroy_drained_qpair(rqpair);
2992 }
2993 
2994 static void
2995 nvmf_rdma_qpair_process_ibv_event(void *ctx)
2996 {
2997 	struct spdk_nvmf_rdma_ibv_event_ctx *event_ctx = ctx;
2998 
2999 	if (event_ctx->rqpair) {
3000 		STAILQ_REMOVE(&event_ctx->rqpair->ibv_events, event_ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3001 		if (event_ctx->cb_fn) {
3002 			event_ctx->cb_fn(event_ctx->rqpair);
3003 		}
3004 	}
3005 	free(event_ctx);
3006 }
3007 
3008 static int
3009 nvmf_rdma_send_qpair_async_event(struct spdk_nvmf_rdma_qpair *rqpair,
3010 				 spdk_nvmf_rdma_qpair_ibv_event fn)
3011 {
3012 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx;
3013 	struct spdk_thread *thr = NULL;
3014 	int rc;
3015 
3016 	if (rqpair->qpair.group) {
3017 		thr = rqpair->qpair.group->thread;
3018 	} else if (rqpair->destruct_channel) {
3019 		thr = spdk_io_channel_get_thread(rqpair->destruct_channel);
3020 	}
3021 
3022 	if (!thr) {
3023 		SPDK_DEBUGLOG(rdma, "rqpair %p has no thread\n", rqpair);
3024 		return -EINVAL;
3025 	}
3026 
3027 	ctx = calloc(1, sizeof(*ctx));
3028 	if (!ctx) {
3029 		return -ENOMEM;
3030 	}
3031 
3032 	ctx->rqpair = rqpair;
3033 	ctx->cb_fn = fn;
3034 	STAILQ_INSERT_TAIL(&rqpair->ibv_events, ctx, link);
3035 
3036 	rc = spdk_thread_send_msg(thr, nvmf_rdma_qpair_process_ibv_event, ctx);
3037 	if (rc) {
3038 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3039 		free(ctx);
3040 	}
3041 
3042 	return rc;
3043 }
3044 
3045 static int
3046 nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
3047 {
3048 	int				rc;
3049 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
3050 	struct ibv_async_event		event;
3051 
3052 	rc = ibv_get_async_event(device->context, &event);
3053 
3054 	if (rc) {
3055 		/* In non-blocking mode -1 means there are no events available */
3056 		return rc;
3057 	}
3058 
3059 	switch (event.event_type) {
3060 	case IBV_EVENT_QP_FATAL:
3061 		rqpair = event.element.qp->qp_context;
3062 		SPDK_ERRLOG("Fatal event received for rqpair %p\n", rqpair);
3063 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3064 				  (uintptr_t)rqpair->cm_id, event.event_type);
3065 		nvmf_rdma_update_ibv_state(rqpair);
3066 		spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3067 		break;
3068 	case IBV_EVENT_QP_LAST_WQE_REACHED:
3069 		/* This event only occurs for shared receive queues. */
3070 		rqpair = event.element.qp->qp_context;
3071 		SPDK_DEBUGLOG(rdma, "Last WQE reached event received for rqpair %p\n", rqpair);
3072 		rc = nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_last_wqe_reached);
3073 		if (rc) {
3074 			SPDK_WARNLOG("Failed to send LAST_WQE_REACHED event. rqpair %p, err %d\n", rqpair, rc);
3075 			rqpair->last_wqe_reached = true;
3076 		}
3077 		break;
3078 	case IBV_EVENT_SQ_DRAINED:
3079 		/* This event occurs frequently in both error and non-error states.
3080 		 * Check if the qpair is in an error state before sending a message. */
3081 		rqpair = event.element.qp->qp_context;
3082 		SPDK_DEBUGLOG(rdma, "Last sq drained event received for rqpair %p\n", rqpair);
3083 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3084 				  (uintptr_t)rqpair->cm_id, event.event_type);
3085 		if (nvmf_rdma_update_ibv_state(rqpair) == IBV_QPS_ERR) {
3086 			spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3087 		}
3088 		break;
3089 	case IBV_EVENT_QP_REQ_ERR:
3090 	case IBV_EVENT_QP_ACCESS_ERR:
3091 	case IBV_EVENT_COMM_EST:
3092 	case IBV_EVENT_PATH_MIG:
3093 	case IBV_EVENT_PATH_MIG_ERR:
3094 		SPDK_NOTICELOG("Async event: %s\n",
3095 			       ibv_event_type_str(event.event_type));
3096 		rqpair = event.element.qp->qp_context;
3097 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3098 				  (uintptr_t)rqpair->cm_id, event.event_type);
3099 		nvmf_rdma_update_ibv_state(rqpair);
3100 		break;
3101 	case IBV_EVENT_CQ_ERR:
3102 	case IBV_EVENT_DEVICE_FATAL:
3103 	case IBV_EVENT_PORT_ACTIVE:
3104 	case IBV_EVENT_PORT_ERR:
3105 	case IBV_EVENT_LID_CHANGE:
3106 	case IBV_EVENT_PKEY_CHANGE:
3107 	case IBV_EVENT_SM_CHANGE:
3108 	case IBV_EVENT_SRQ_ERR:
3109 	case IBV_EVENT_SRQ_LIMIT_REACHED:
3110 	case IBV_EVENT_CLIENT_REREGISTER:
3111 	case IBV_EVENT_GID_CHANGE:
3112 	default:
3113 		SPDK_NOTICELOG("Async event: %s\n",
3114 			       ibv_event_type_str(event.event_type));
3115 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
3116 		break;
3117 	}
3118 	ibv_ack_async_event(&event);
3119 
3120 	return 0;
3121 }
3122 
3123 static void
3124 nvmf_process_ib_events(struct spdk_nvmf_rdma_device *device, uint32_t max_events)
3125 {
3126 	int rc = 0;
3127 	uint32_t i = 0;
3128 
3129 	for (i = 0; i < max_events; i++) {
3130 		rc = nvmf_process_ib_event(device);
3131 		if (rc) {
3132 			break;
3133 		}
3134 	}
3135 
3136 	SPDK_DEBUGLOG(rdma, "Device %s: %u events processed\n", device->context->device->name, i);
3137 }
3138 
3139 static uint32_t
3140 nvmf_rdma_accept(struct spdk_nvmf_transport *transport)
3141 {
3142 	int	nfds, i = 0;
3143 	struct spdk_nvmf_rdma_transport *rtransport;
3144 	struct spdk_nvmf_rdma_device *device, *tmp;
3145 	uint32_t count;
3146 
3147 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3148 	count = nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
3149 
3150 	if (nfds <= 0) {
3151 		return 0;
3152 	}
3153 
3154 	/* The first poll descriptor is RDMA CM event */
3155 	if (rtransport->poll_fds[i++].revents & POLLIN) {
3156 		nvmf_process_cm_event(transport);
3157 		nfds--;
3158 	}
3159 
3160 	if (nfds == 0) {
3161 		return count;
3162 	}
3163 
3164 	/* Second and subsequent poll descriptors are IB async events */
3165 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
3166 		if (rtransport->poll_fds[i++].revents & POLLIN) {
3167 			nvmf_process_ib_events(device, 32);
3168 			nfds--;
3169 		}
3170 	}
3171 	/* check all flagged fd's have been served */
3172 	assert(nfds == 0);
3173 
3174 	return count;
3175 }
3176 
3177 static void
3178 nvmf_rdma_cdata_init(struct spdk_nvmf_transport *transport, struct spdk_nvmf_subsystem *subsystem,
3179 		     struct spdk_nvmf_ctrlr_data *cdata)
3180 {
3181 	cdata->nvmf_specific.msdbd = SPDK_NVMF_MAX_SGL_ENTRIES;
3182 
3183 	/* Disable in-capsule data transfer for RDMA controller when dif_insert_or_strip is enabled
3184 	since in-capsule data only works with NVME drives that support SGL memory layout */
3185 	if (transport->opts.dif_insert_or_strip) {
3186 		cdata->nvmf_specific.ioccsz = sizeof(struct spdk_nvme_cmd) / 16;
3187 	}
3188 }
3189 
3190 static void
3191 nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
3192 		   struct spdk_nvme_transport_id *trid,
3193 		   struct spdk_nvmf_discovery_log_page_entry *entry)
3194 {
3195 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
3196 	entry->adrfam = trid->adrfam;
3197 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
3198 
3199 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
3200 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
3201 
3202 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
3203 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
3204 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
3205 }
3206 
3207 static void
3208 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
3209 
3210 static struct spdk_nvmf_transport_poll_group *
3211 nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
3212 {
3213 	struct spdk_nvmf_rdma_transport		*rtransport;
3214 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3215 	struct spdk_nvmf_rdma_poller		*poller;
3216 	struct spdk_nvmf_rdma_device		*device;
3217 	struct ibv_srq_init_attr		srq_init_attr;
3218 	struct spdk_nvmf_rdma_resource_opts	opts;
3219 	int					num_cqe;
3220 
3221 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3222 
3223 	rgroup = calloc(1, sizeof(*rgroup));
3224 	if (!rgroup) {
3225 		return NULL;
3226 	}
3227 
3228 	TAILQ_INIT(&rgroup->pollers);
3229 
3230 	pthread_mutex_lock(&rtransport->lock);
3231 	TAILQ_FOREACH(device, &rtransport->devices, link) {
3232 		poller = calloc(1, sizeof(*poller));
3233 		if (!poller) {
3234 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
3235 			nvmf_rdma_poll_group_destroy(&rgroup->group);
3236 			pthread_mutex_unlock(&rtransport->lock);
3237 			return NULL;
3238 		}
3239 
3240 		poller->device = device;
3241 		poller->group = rgroup;
3242 
3243 		TAILQ_INIT(&poller->qpairs);
3244 		STAILQ_INIT(&poller->qpairs_pending_send);
3245 		STAILQ_INIT(&poller->qpairs_pending_recv);
3246 
3247 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
3248 		if (rtransport->rdma_opts.no_srq == false && device->num_srq < device->attr.max_srq) {
3249 			poller->max_srq_depth = rtransport->rdma_opts.max_srq_depth;
3250 
3251 			device->num_srq++;
3252 			memset(&srq_init_attr, 0, sizeof(struct ibv_srq_init_attr));
3253 			srq_init_attr.attr.max_wr = poller->max_srq_depth;
3254 			srq_init_attr.attr.max_sge = spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
3255 			poller->srq = ibv_create_srq(device->pd, &srq_init_attr);
3256 			if (!poller->srq) {
3257 				SPDK_ERRLOG("Unable to create shared receive queue, errno %d\n", errno);
3258 				nvmf_rdma_poll_group_destroy(&rgroup->group);
3259 				pthread_mutex_unlock(&rtransport->lock);
3260 				return NULL;
3261 			}
3262 
3263 			opts.qp = poller->srq;
3264 			opts.pd = device->pd;
3265 			opts.qpair = NULL;
3266 			opts.shared = true;
3267 			opts.max_queue_depth = poller->max_srq_depth;
3268 			opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
3269 
3270 			poller->resources = nvmf_rdma_resources_create(&opts);
3271 			if (!poller->resources) {
3272 				SPDK_ERRLOG("Unable to allocate resources for shared receive queue.\n");
3273 				nvmf_rdma_poll_group_destroy(&rgroup->group);
3274 				pthread_mutex_unlock(&rtransport->lock);
3275 				return NULL;
3276 			}
3277 		}
3278 
3279 		/*
3280 		 * When using an srq, we can limit the completion queue at startup.
3281 		 * The following formula represents the calculation:
3282 		 * num_cqe = num_recv + num_data_wr + num_send_wr.
3283 		 * where num_recv=num_data_wr=and num_send_wr=poller->max_srq_depth
3284 		 */
3285 		if (poller->srq) {
3286 			num_cqe = poller->max_srq_depth * 3;
3287 		} else {
3288 			num_cqe = DEFAULT_NVMF_RDMA_CQ_SIZE;
3289 		}
3290 
3291 		poller->cq = ibv_create_cq(device->context, num_cqe, poller, NULL, 0);
3292 		if (!poller->cq) {
3293 			SPDK_ERRLOG("Unable to create completion queue\n");
3294 			nvmf_rdma_poll_group_destroy(&rgroup->group);
3295 			pthread_mutex_unlock(&rtransport->lock);
3296 			return NULL;
3297 		}
3298 		poller->num_cqe = num_cqe;
3299 	}
3300 
3301 	TAILQ_INSERT_TAIL(&rtransport->poll_groups, rgroup, link);
3302 	if (rtransport->conn_sched.next_admin_pg == NULL) {
3303 		rtransport->conn_sched.next_admin_pg = rgroup;
3304 		rtransport->conn_sched.next_io_pg = rgroup;
3305 	}
3306 
3307 	pthread_mutex_unlock(&rtransport->lock);
3308 	return &rgroup->group;
3309 }
3310 
3311 static struct spdk_nvmf_transport_poll_group *
3312 nvmf_rdma_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
3313 {
3314 	struct spdk_nvmf_rdma_transport *rtransport;
3315 	struct spdk_nvmf_rdma_poll_group **pg;
3316 	struct spdk_nvmf_transport_poll_group *result;
3317 
3318 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
3319 
3320 	pthread_mutex_lock(&rtransport->lock);
3321 
3322 	if (TAILQ_EMPTY(&rtransport->poll_groups)) {
3323 		pthread_mutex_unlock(&rtransport->lock);
3324 		return NULL;
3325 	}
3326 
3327 	if (qpair->qid == 0) {
3328 		pg = &rtransport->conn_sched.next_admin_pg;
3329 	} else {
3330 		pg = &rtransport->conn_sched.next_io_pg;
3331 	}
3332 
3333 	assert(*pg != NULL);
3334 
3335 	result = &(*pg)->group;
3336 
3337 	*pg = TAILQ_NEXT(*pg, link);
3338 	if (*pg == NULL) {
3339 		*pg = TAILQ_FIRST(&rtransport->poll_groups);
3340 	}
3341 
3342 	pthread_mutex_unlock(&rtransport->lock);
3343 
3344 	return result;
3345 }
3346 
3347 static void
3348 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
3349 {
3350 	struct spdk_nvmf_rdma_poll_group	*rgroup, *next_rgroup;
3351 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
3352 	struct spdk_nvmf_rdma_qpair		*qpair, *tmp_qpair;
3353 	struct spdk_nvmf_rdma_transport		*rtransport;
3354 
3355 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3356 	if (!rgroup) {
3357 		return;
3358 	}
3359 
3360 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
3361 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
3362 
3363 		TAILQ_FOREACH_SAFE(qpair, &poller->qpairs, link, tmp_qpair) {
3364 			nvmf_rdma_qpair_destroy(qpair);
3365 		}
3366 
3367 		if (poller->srq) {
3368 			if (poller->resources) {
3369 				nvmf_rdma_resources_destroy(poller->resources);
3370 			}
3371 			ibv_destroy_srq(poller->srq);
3372 			SPDK_DEBUGLOG(rdma, "Destroyed RDMA shared queue %p\n", poller->srq);
3373 		}
3374 
3375 		if (poller->cq) {
3376 			ibv_destroy_cq(poller->cq);
3377 		}
3378 
3379 		free(poller);
3380 	}
3381 
3382 	if (rgroup->group.transport == NULL) {
3383 		/* Transport can be NULL when nvmf_rdma_poll_group_create()
3384 		 * calls this function directly in a failure path. */
3385 		free(rgroup);
3386 		return;
3387 	}
3388 
3389 	rtransport = SPDK_CONTAINEROF(rgroup->group.transport, struct spdk_nvmf_rdma_transport, transport);
3390 
3391 	pthread_mutex_lock(&rtransport->lock);
3392 	next_rgroup = TAILQ_NEXT(rgroup, link);
3393 	TAILQ_REMOVE(&rtransport->poll_groups, rgroup, link);
3394 	if (next_rgroup == NULL) {
3395 		next_rgroup = TAILQ_FIRST(&rtransport->poll_groups);
3396 	}
3397 	if (rtransport->conn_sched.next_admin_pg == rgroup) {
3398 		rtransport->conn_sched.next_admin_pg = next_rgroup;
3399 	}
3400 	if (rtransport->conn_sched.next_io_pg == rgroup) {
3401 		rtransport->conn_sched.next_io_pg = next_rgroup;
3402 	}
3403 	pthread_mutex_unlock(&rtransport->lock);
3404 
3405 	free(rgroup);
3406 }
3407 
3408 static void
3409 nvmf_rdma_qpair_reject_connection(struct spdk_nvmf_rdma_qpair *rqpair)
3410 {
3411 	if (rqpair->cm_id != NULL) {
3412 		nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
3413 	}
3414 }
3415 
3416 static int
3417 nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
3418 			 struct spdk_nvmf_qpair *qpair)
3419 {
3420 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3421 	struct spdk_nvmf_rdma_qpair		*rqpair;
3422 	struct spdk_nvmf_rdma_device		*device;
3423 	struct spdk_nvmf_rdma_poller		*poller;
3424 	int					rc;
3425 
3426 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3427 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3428 
3429 	device = rqpair->device;
3430 
3431 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
3432 		if (poller->device == device) {
3433 			break;
3434 		}
3435 	}
3436 
3437 	if (!poller) {
3438 		SPDK_ERRLOG("No poller found for device.\n");
3439 		return -1;
3440 	}
3441 
3442 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
3443 	rqpair->poller = poller;
3444 	rqpair->srq = rqpair->poller->srq;
3445 
3446 	rc = nvmf_rdma_qpair_initialize(qpair);
3447 	if (rc < 0) {
3448 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
3449 		return -1;
3450 	}
3451 
3452 	rc = nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
3453 	if (rc) {
3454 		/* Try to reject, but we probably can't */
3455 		nvmf_rdma_qpair_reject_connection(rqpair);
3456 		return -1;
3457 	}
3458 
3459 	nvmf_rdma_update_ibv_state(rqpair);
3460 
3461 	return 0;
3462 }
3463 
3464 static int
3465 nvmf_rdma_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
3466 			    struct spdk_nvmf_qpair *qpair)
3467 {
3468 	struct spdk_nvmf_rdma_qpair		*rqpair;
3469 
3470 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3471 	assert(group->transport->tgt != NULL);
3472 
3473 	rqpair->destruct_channel = spdk_get_io_channel(group->transport->tgt);
3474 
3475 	if (!rqpair->destruct_channel) {
3476 		SPDK_WARNLOG("failed to get io_channel, qpair %p\n", qpair);
3477 		return 0;
3478 	}
3479 
3480 	/* Sanity check that we get io_channel on the correct thread */
3481 	if (qpair->group) {
3482 		assert(qpair->group->thread == spdk_io_channel_get_thread(rqpair->destruct_channel));
3483 	}
3484 
3485 	return 0;
3486 }
3487 
3488 static int
3489 nvmf_rdma_request_free(struct spdk_nvmf_request *req)
3490 {
3491 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
3492 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3493 			struct spdk_nvmf_rdma_transport, transport);
3494 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3495 					      struct spdk_nvmf_rdma_qpair, qpair);
3496 
3497 	/*
3498 	 * AER requests are freed when a qpair is destroyed. The recv corresponding to that request
3499 	 * needs to be returned to the shared receive queue or the poll group will eventually be
3500 	 * starved of RECV structures.
3501 	 */
3502 	if (rqpair->srq && rdma_req->recv) {
3503 		int rc;
3504 		struct ibv_recv_wr *bad_recv_wr;
3505 
3506 		rc = ibv_post_srq_recv(rqpair->srq, &rdma_req->recv->wr, &bad_recv_wr);
3507 		if (rc) {
3508 			SPDK_ERRLOG("Unable to re-post rx descriptor\n");
3509 		}
3510 	}
3511 
3512 	_nvmf_rdma_request_free(rdma_req, rtransport);
3513 	return 0;
3514 }
3515 
3516 static int
3517 nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
3518 {
3519 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3520 			struct spdk_nvmf_rdma_transport, transport);
3521 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
3522 			struct spdk_nvmf_rdma_request, req);
3523 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3524 			struct spdk_nvmf_rdma_qpair, qpair);
3525 
3526 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3527 		/* The connection is alive, so process the request as normal */
3528 		rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
3529 	} else {
3530 		/* The connection is dead. Move the request directly to the completed state. */
3531 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3532 	}
3533 
3534 	nvmf_rdma_request_process(rtransport, rdma_req);
3535 
3536 	return 0;
3537 }
3538 
3539 static void
3540 nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair,
3541 		      spdk_nvmf_transport_qpair_fini_cb cb_fn, void *cb_arg)
3542 {
3543 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3544 
3545 	rqpair->to_close = true;
3546 
3547 	/* This happens only when the qpair is disconnected before
3548 	 * it is added to the poll group. Since there is no poll group,
3549 	 * the RDMA qp has not been initialized yet and the RDMA CM
3550 	 * event has not yet been acknowledged, so we need to reject it.
3551 	 */
3552 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
3553 		nvmf_rdma_qpair_reject_connection(rqpair);
3554 		nvmf_rdma_qpair_destroy(rqpair);
3555 		return;
3556 	}
3557 
3558 	if (rqpair->rdma_qp) {
3559 		spdk_rdma_qp_disconnect(rqpair->rdma_qp);
3560 	}
3561 
3562 	nvmf_rdma_destroy_drained_qpair(rqpair);
3563 
3564 	if (cb_fn) {
3565 		cb_fn(cb_arg);
3566 	}
3567 }
3568 
3569 static struct spdk_nvmf_rdma_qpair *
3570 get_rdma_qpair_from_wc(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_wc *wc)
3571 {
3572 	struct spdk_nvmf_rdma_qpair *rqpair;
3573 	/* @todo: improve QP search */
3574 	TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
3575 		if (wc->qp_num == rqpair->rdma_qp->qp->qp_num) {
3576 			return rqpair;
3577 		}
3578 	}
3579 	SPDK_ERRLOG("Didn't find QP with qp_num %u\n", wc->qp_num);
3580 	return NULL;
3581 }
3582 
3583 #ifdef DEBUG
3584 static int
3585 nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
3586 {
3587 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
3588 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
3589 }
3590 #endif
3591 
3592 static void
3593 _poller_reset_failed_recvs(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_recv_wr *bad_recv_wr,
3594 			   int rc)
3595 {
3596 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3597 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3598 
3599 	SPDK_ERRLOG("Failed to post a recv for the poller %p with errno %d\n", rpoller, -rc);
3600 	while (bad_recv_wr != NULL) {
3601 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_recv_wr->wr_id;
3602 		rdma_recv = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3603 
3604 		rdma_recv->qpair->current_recv_depth++;
3605 		bad_recv_wr = bad_recv_wr->next;
3606 		SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rdma_recv->qpair, -rc);
3607 		spdk_nvmf_qpair_disconnect(&rdma_recv->qpair->qpair, NULL, NULL);
3608 	}
3609 }
3610 
3611 static void
3612 _qp_reset_failed_recvs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *bad_recv_wr, int rc)
3613 {
3614 	SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rqpair, -rc);
3615 	while (bad_recv_wr != NULL) {
3616 		bad_recv_wr = bad_recv_wr->next;
3617 		rqpair->current_recv_depth++;
3618 	}
3619 	spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3620 }
3621 
3622 static void
3623 _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
3624 		     struct spdk_nvmf_rdma_poller *rpoller)
3625 {
3626 	struct spdk_nvmf_rdma_qpair	*rqpair;
3627 	struct ibv_recv_wr		*bad_recv_wr;
3628 	int				rc;
3629 
3630 	if (rpoller->srq) {
3631 		if (rpoller->resources->recvs_to_post.first != NULL) {
3632 			rc = ibv_post_srq_recv(rpoller->srq, rpoller->resources->recvs_to_post.first, &bad_recv_wr);
3633 			if (rc) {
3634 				_poller_reset_failed_recvs(rpoller, bad_recv_wr, rc);
3635 			}
3636 			rpoller->resources->recvs_to_post.first = NULL;
3637 			rpoller->resources->recvs_to_post.last = NULL;
3638 		}
3639 	} else {
3640 		while (!STAILQ_EMPTY(&rpoller->qpairs_pending_recv)) {
3641 			rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_recv);
3642 			assert(rqpair->resources->recvs_to_post.first != NULL);
3643 			rc = ibv_post_recv(rqpair->rdma_qp->qp, rqpair->resources->recvs_to_post.first, &bad_recv_wr);
3644 			if (rc) {
3645 				_qp_reset_failed_recvs(rqpair, bad_recv_wr, rc);
3646 			}
3647 			rqpair->resources->recvs_to_post.first = NULL;
3648 			rqpair->resources->recvs_to_post.last = NULL;
3649 			STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_recv, recv_link);
3650 		}
3651 	}
3652 }
3653 
3654 static void
3655 _qp_reset_failed_sends(struct spdk_nvmf_rdma_transport *rtransport,
3656 		       struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_send_wr *bad_wr, int rc)
3657 {
3658 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3659 	struct spdk_nvmf_rdma_request	*prev_rdma_req = NULL, *cur_rdma_req = NULL;
3660 
3661 	SPDK_ERRLOG("Failed to post a send for the qpair %p with errno %d\n", rqpair, -rc);
3662 	for (; bad_wr != NULL; bad_wr = bad_wr->next) {
3663 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_wr->wr_id;
3664 		assert(rqpair->current_send_depth > 0);
3665 		rqpair->current_send_depth--;
3666 		switch (bad_rdma_wr->type) {
3667 		case RDMA_WR_TYPE_DATA:
3668 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3669 			if (bad_wr->opcode == IBV_WR_RDMA_READ) {
3670 				assert(rqpair->current_read_depth > 0);
3671 				rqpair->current_read_depth--;
3672 			}
3673 			break;
3674 		case RDMA_WR_TYPE_SEND:
3675 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3676 			break;
3677 		default:
3678 			SPDK_ERRLOG("Found a RECV in the list of pending SEND requests for qpair %p\n", rqpair);
3679 			prev_rdma_req = cur_rdma_req;
3680 			continue;
3681 		}
3682 
3683 		if (prev_rdma_req == cur_rdma_req) {
3684 			/* this request was handled by an earlier wr. i.e. we were performing an nvme read. */
3685 			/* We only have to check against prev_wr since each requests wrs are contiguous in this list. */
3686 			continue;
3687 		}
3688 
3689 		switch (cur_rdma_req->state) {
3690 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
3691 			cur_rdma_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
3692 			cur_rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
3693 			break;
3694 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
3695 		case RDMA_REQUEST_STATE_COMPLETING:
3696 			cur_rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3697 			break;
3698 		default:
3699 			SPDK_ERRLOG("Found a request in a bad state %d when draining pending SEND requests for qpair %p\n",
3700 				    cur_rdma_req->state, rqpair);
3701 			continue;
3702 		}
3703 
3704 		nvmf_rdma_request_process(rtransport, cur_rdma_req);
3705 		prev_rdma_req = cur_rdma_req;
3706 	}
3707 
3708 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3709 		/* Disconnect the connection. */
3710 		spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3711 	}
3712 
3713 }
3714 
3715 static void
3716 _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
3717 		     struct spdk_nvmf_rdma_poller *rpoller)
3718 {
3719 	struct spdk_nvmf_rdma_qpair	*rqpair;
3720 	struct ibv_send_wr		*bad_wr = NULL;
3721 	int				rc;
3722 
3723 	while (!STAILQ_EMPTY(&rpoller->qpairs_pending_send)) {
3724 		rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_send);
3725 		rc = spdk_rdma_qp_flush_send_wrs(rqpair->rdma_qp, &bad_wr);
3726 
3727 		/* bad wr always points to the first wr that failed. */
3728 		if (rc) {
3729 			_qp_reset_failed_sends(rtransport, rqpair, bad_wr, rc);
3730 		}
3731 		STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_send, send_link);
3732 	}
3733 }
3734 
3735 static const char *
3736 nvmf_rdma_wr_type_str(enum spdk_nvmf_rdma_wr_type wr_type)
3737 {
3738 	switch (wr_type) {
3739 	case RDMA_WR_TYPE_RECV:
3740 		return "RECV";
3741 	case RDMA_WR_TYPE_SEND:
3742 		return "SEND";
3743 	case RDMA_WR_TYPE_DATA:
3744 		return "DATA";
3745 	default:
3746 		SPDK_ERRLOG("Unknown WR type %d\n", wr_type);
3747 		SPDK_UNREACHABLE();
3748 	}
3749 }
3750 
3751 static inline void
3752 nvmf_rdma_log_wc_status(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_wc *wc)
3753 {
3754 	enum spdk_nvmf_rdma_wr_type wr_type = ((struct spdk_nvmf_rdma_wr *)wc->wr_id)->type;
3755 
3756 	if (wc->status == IBV_WC_WR_FLUSH_ERR) {
3757 		/* If qpair is in ERR state, we will receive completions for all posted and not completed
3758 		 * Work Requests with IBV_WC_WR_FLUSH_ERR status. Don't log an error in that case */
3759 		SPDK_DEBUGLOG(rdma,
3760 			      "Error on CQ %p, (qp state %d ibv_state %d) request 0x%lu, type %s, status: (%d): %s\n",
3761 			      rqpair->poller->cq, rqpair->qpair.state, rqpair->ibv_state, wc->wr_id,
3762 			      nvmf_rdma_wr_type_str(wr_type), wc->status, ibv_wc_status_str(wc->status));
3763 	} else {
3764 		SPDK_ERRLOG("Error on CQ %p, (qp state %d ibv_state %d) request 0x%lu, type %s, status: (%d): %s\n",
3765 			    rqpair->poller->cq, rqpair->qpair.state, rqpair->ibv_state, wc->wr_id,
3766 			    nvmf_rdma_wr_type_str(wr_type), wc->status, ibv_wc_status_str(wc->status));
3767 	}
3768 }
3769 
3770 static int
3771 nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
3772 		      struct spdk_nvmf_rdma_poller *rpoller)
3773 {
3774 	struct ibv_wc wc[32];
3775 	struct spdk_nvmf_rdma_wr	*rdma_wr;
3776 	struct spdk_nvmf_rdma_request	*rdma_req;
3777 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3778 	struct spdk_nvmf_rdma_qpair	*rqpair;
3779 	int reaped, i;
3780 	int count = 0;
3781 	bool error = false;
3782 	uint64_t poll_tsc = spdk_get_ticks();
3783 
3784 	/* Poll for completing operations. */
3785 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
3786 	if (reaped < 0) {
3787 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
3788 			    errno, spdk_strerror(errno));
3789 		return -1;
3790 	}
3791 
3792 	rpoller->stat.polls++;
3793 	rpoller->stat.completions += reaped;
3794 
3795 	for (i = 0; i < reaped; i++) {
3796 
3797 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
3798 
3799 		switch (rdma_wr->type) {
3800 		case RDMA_WR_TYPE_SEND:
3801 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3802 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3803 
3804 			if (!wc[i].status) {
3805 				count++;
3806 				assert(wc[i].opcode == IBV_WC_SEND);
3807 				assert(nvmf_rdma_req_is_completing(rdma_req));
3808 			}
3809 
3810 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3811 			/* RDMA_WRITE operation completed. +1 since it was chained with rsp WR */
3812 			rqpair->current_send_depth -= rdma_req->num_outstanding_data_wr + 1;
3813 			rdma_req->num_outstanding_data_wr = 0;
3814 
3815 			nvmf_rdma_request_process(rtransport, rdma_req);
3816 			break;
3817 		case RDMA_WR_TYPE_RECV:
3818 			/* rdma_recv->qpair will be invalid if using an SRQ.  In that case we have to get the qpair from the wc. */
3819 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3820 			if (rpoller->srq != NULL) {
3821 				rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
3822 				/* It is possible that there are still some completions for destroyed QP
3823 				 * associated with SRQ. We just ignore these late completions and re-post
3824 				 * receive WRs back to SRQ.
3825 				 */
3826 				if (spdk_unlikely(NULL == rdma_recv->qpair)) {
3827 					struct ibv_recv_wr *bad_wr;
3828 					int rc;
3829 
3830 					rdma_recv->wr.next = NULL;
3831 					rc = ibv_post_srq_recv(rpoller->srq,
3832 							       &rdma_recv->wr,
3833 							       &bad_wr);
3834 					if (rc) {
3835 						SPDK_ERRLOG("Failed to re-post recv WR to SRQ, err %d\n", rc);
3836 					}
3837 					continue;
3838 				}
3839 			}
3840 			rqpair = rdma_recv->qpair;
3841 
3842 			assert(rqpair != NULL);
3843 			if (!wc[i].status) {
3844 				assert(wc[i].opcode == IBV_WC_RECV);
3845 				if (rqpair->current_recv_depth >= rqpair->max_queue_depth) {
3846 					spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3847 					break;
3848 				}
3849 			}
3850 
3851 			rdma_recv->wr.next = NULL;
3852 			rqpair->current_recv_depth++;
3853 			rdma_recv->receive_tsc = poll_tsc;
3854 			rpoller->stat.requests++;
3855 			STAILQ_INSERT_TAIL(&rqpair->resources->incoming_queue, rdma_recv, link);
3856 			break;
3857 		case RDMA_WR_TYPE_DATA:
3858 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3859 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3860 
3861 			assert(rdma_req->num_outstanding_data_wr > 0);
3862 
3863 			rqpair->current_send_depth--;
3864 			rdma_req->num_outstanding_data_wr--;
3865 			if (!wc[i].status) {
3866 				assert(wc[i].opcode == IBV_WC_RDMA_READ);
3867 				rqpair->current_read_depth--;
3868 				/* wait for all outstanding reads associated with the same rdma_req to complete before proceeding. */
3869 				if (rdma_req->num_outstanding_data_wr == 0) {
3870 					rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
3871 					nvmf_rdma_request_process(rtransport, rdma_req);
3872 				}
3873 			} else {
3874 				/* If the data transfer fails still force the queue into the error state,
3875 				 * if we were performing an RDMA_READ, we need to force the request into a
3876 				 * completed state since it wasn't linked to a send. However, in the RDMA_WRITE
3877 				 * case, we should wait for the SEND to complete. */
3878 				if (rdma_req->data.wr.opcode == IBV_WR_RDMA_READ) {
3879 					rqpair->current_read_depth--;
3880 					if (rdma_req->num_outstanding_data_wr == 0) {
3881 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3882 					}
3883 				}
3884 			}
3885 			break;
3886 		default:
3887 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
3888 			continue;
3889 		}
3890 
3891 		/* Handle error conditions */
3892 		if (wc[i].status) {
3893 			nvmf_rdma_update_ibv_state(rqpair);
3894 			nvmf_rdma_log_wc_status(rqpair, &wc[i]);
3895 
3896 			error = true;
3897 
3898 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3899 				/* Disconnect the connection. */
3900 				spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3901 			} else {
3902 				nvmf_rdma_destroy_drained_qpair(rqpair);
3903 			}
3904 			continue;
3905 		}
3906 
3907 		nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3908 
3909 		if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
3910 			nvmf_rdma_destroy_drained_qpair(rqpair);
3911 		}
3912 	}
3913 
3914 	if (error == true) {
3915 		return -1;
3916 	}
3917 
3918 	/* submit outstanding work requests. */
3919 	_poller_submit_recvs(rtransport, rpoller);
3920 	_poller_submit_sends(rtransport, rpoller);
3921 
3922 	return count;
3923 }
3924 
3925 static int
3926 nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3927 {
3928 	struct spdk_nvmf_rdma_transport *rtransport;
3929 	struct spdk_nvmf_rdma_poll_group *rgroup;
3930 	struct spdk_nvmf_rdma_poller	*rpoller;
3931 	int				count, rc;
3932 
3933 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
3934 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3935 
3936 	count = 0;
3937 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3938 		rc = nvmf_rdma_poller_poll(rtransport, rpoller);
3939 		if (rc < 0) {
3940 			return rc;
3941 		}
3942 		count += rc;
3943 	}
3944 
3945 	return count;
3946 }
3947 
3948 static int
3949 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
3950 			  struct spdk_nvme_transport_id *trid,
3951 			  bool peer)
3952 {
3953 	struct sockaddr *saddr;
3954 	uint16_t port;
3955 
3956 	spdk_nvme_trid_populate_transport(trid, SPDK_NVME_TRANSPORT_RDMA);
3957 
3958 	if (peer) {
3959 		saddr = rdma_get_peer_addr(id);
3960 	} else {
3961 		saddr = rdma_get_local_addr(id);
3962 	}
3963 	switch (saddr->sa_family) {
3964 	case AF_INET: {
3965 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
3966 
3967 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3968 		inet_ntop(AF_INET, &saddr_in->sin_addr,
3969 			  trid->traddr, sizeof(trid->traddr));
3970 		if (peer) {
3971 			port = ntohs(rdma_get_dst_port(id));
3972 		} else {
3973 			port = ntohs(rdma_get_src_port(id));
3974 		}
3975 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3976 		break;
3977 	}
3978 	case AF_INET6: {
3979 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
3980 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3981 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
3982 			  trid->traddr, sizeof(trid->traddr));
3983 		if (peer) {
3984 			port = ntohs(rdma_get_dst_port(id));
3985 		} else {
3986 			port = ntohs(rdma_get_src_port(id));
3987 		}
3988 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3989 		break;
3990 	}
3991 	default:
3992 		return -1;
3993 
3994 	}
3995 
3996 	return 0;
3997 }
3998 
3999 static int
4000 nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
4001 			      struct spdk_nvme_transport_id *trid)
4002 {
4003 	struct spdk_nvmf_rdma_qpair	*rqpair;
4004 
4005 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4006 
4007 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
4008 }
4009 
4010 static int
4011 nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
4012 			       struct spdk_nvme_transport_id *trid)
4013 {
4014 	struct spdk_nvmf_rdma_qpair	*rqpair;
4015 
4016 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4017 
4018 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
4019 }
4020 
4021 static int
4022 nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
4023 				struct spdk_nvme_transport_id *trid)
4024 {
4025 	struct spdk_nvmf_rdma_qpair	*rqpair;
4026 
4027 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4028 
4029 	return nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
4030 }
4031 
4032 void
4033 spdk_nvmf_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
4034 {
4035 	g_nvmf_hooks = *hooks;
4036 }
4037 
4038 static void
4039 nvmf_rdma_request_set_abort_status(struct spdk_nvmf_request *req,
4040 				   struct spdk_nvmf_rdma_request *rdma_req_to_abort)
4041 {
4042 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
4043 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_BY_REQUEST;
4044 
4045 	rdma_req_to_abort->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
4046 
4047 	req->rsp->nvme_cpl.cdw0 &= ~1U;	/* Command was successfully aborted. */
4048 }
4049 
4050 static int
4051 _nvmf_rdma_qpair_abort_request(void *ctx)
4052 {
4053 	struct spdk_nvmf_request *req = ctx;
4054 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = SPDK_CONTAINEROF(
4055 				req->req_to_abort, struct spdk_nvmf_rdma_request, req);
4056 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(req->req_to_abort->qpair,
4057 					      struct spdk_nvmf_rdma_qpair, qpair);
4058 	int rc;
4059 
4060 	spdk_poller_unregister(&req->poller);
4061 
4062 	switch (rdma_req_to_abort->state) {
4063 	case RDMA_REQUEST_STATE_EXECUTING:
4064 		rc = nvmf_ctrlr_abort_request(req);
4065 		if (rc == SPDK_NVMF_REQUEST_EXEC_STATUS_ASYNCHRONOUS) {
4066 			return SPDK_POLLER_BUSY;
4067 		}
4068 		break;
4069 
4070 	case RDMA_REQUEST_STATE_NEED_BUFFER:
4071 		STAILQ_REMOVE(&rqpair->poller->group->group.pending_buf_queue,
4072 			      &rdma_req_to_abort->req, spdk_nvmf_request, buf_link);
4073 
4074 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4075 		break;
4076 
4077 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
4078 		STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req_to_abort,
4079 			      spdk_nvmf_rdma_request, state_link);
4080 
4081 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4082 		break;
4083 
4084 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
4085 		STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req_to_abort,
4086 			      spdk_nvmf_rdma_request, state_link);
4087 
4088 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4089 		break;
4090 
4091 	case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
4092 		if (spdk_get_ticks() < req->timeout_tsc) {
4093 			req->poller = SPDK_POLLER_REGISTER(_nvmf_rdma_qpair_abort_request, req, 0);
4094 			return SPDK_POLLER_BUSY;
4095 		}
4096 		break;
4097 
4098 	default:
4099 		break;
4100 	}
4101 
4102 	spdk_nvmf_request_complete(req);
4103 	return SPDK_POLLER_BUSY;
4104 }
4105 
4106 static void
4107 nvmf_rdma_qpair_abort_request(struct spdk_nvmf_qpair *qpair,
4108 			      struct spdk_nvmf_request *req)
4109 {
4110 	struct spdk_nvmf_rdma_qpair *rqpair;
4111 	struct spdk_nvmf_rdma_transport *rtransport;
4112 	struct spdk_nvmf_transport *transport;
4113 	uint16_t cid;
4114 	uint32_t i, max_req_count;
4115 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = NULL, *rdma_req;
4116 
4117 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4118 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
4119 	transport = &rtransport->transport;
4120 
4121 	cid = req->cmd->nvme_cmd.cdw10_bits.abort.cid;
4122 	max_req_count = rqpair->srq == NULL ? rqpair->max_queue_depth : rqpair->poller->max_srq_depth;
4123 
4124 	for (i = 0; i < max_req_count; i++) {
4125 		rdma_req = &rqpair->resources->reqs[i];
4126 		/* When SRQ == NULL, rqpair has its own requests and req.qpair pointer always points to the qpair
4127 		 * When SRQ != NULL all rqpairs share common requests and qpair pointer is assigned when we start to
4128 		 * process a request. So in both cases all requests which are not in FREE state have valid qpair ptr */
4129 		if (rdma_req->state != RDMA_REQUEST_STATE_FREE && rdma_req->req.cmd->nvme_cmd.cid == cid &&
4130 		    rdma_req->req.qpair == qpair) {
4131 			rdma_req_to_abort = rdma_req;
4132 			break;
4133 		}
4134 	}
4135 
4136 	if (rdma_req_to_abort == NULL) {
4137 		spdk_nvmf_request_complete(req);
4138 		return;
4139 	}
4140 
4141 	req->req_to_abort = &rdma_req_to_abort->req;
4142 	req->timeout_tsc = spdk_get_ticks() +
4143 			   transport->opts.abort_timeout_sec * spdk_get_ticks_hz();
4144 	req->poller = NULL;
4145 
4146 	_nvmf_rdma_qpair_abort_request(req);
4147 }
4148 
4149 static int
4150 nvmf_rdma_poll_group_get_stat(struct spdk_nvmf_tgt *tgt,
4151 			      struct spdk_nvmf_transport_poll_group_stat **stat)
4152 {
4153 	struct spdk_io_channel *ch;
4154 	struct spdk_nvmf_poll_group *group;
4155 	struct spdk_nvmf_transport_poll_group *tgroup;
4156 	struct spdk_nvmf_rdma_poll_group *rgroup;
4157 	struct spdk_nvmf_rdma_poller *rpoller;
4158 	struct spdk_nvmf_rdma_device_stat *device_stat;
4159 	uint64_t num_devices = 0;
4160 
4161 	if (tgt == NULL || stat == NULL) {
4162 		return -EINVAL;
4163 	}
4164 
4165 	ch = spdk_get_io_channel(tgt);
4166 	group = spdk_io_channel_get_ctx(ch);;
4167 	spdk_put_io_channel(ch);
4168 	TAILQ_FOREACH(tgroup, &group->tgroups, link) {
4169 		if (SPDK_NVME_TRANSPORT_RDMA == tgroup->transport->ops->type) {
4170 			*stat = calloc(1, sizeof(struct spdk_nvmf_transport_poll_group_stat));
4171 			if (!*stat) {
4172 				SPDK_ERRLOG("Failed to allocate memory for NVMf RDMA statistics\n");
4173 				return -ENOMEM;
4174 			}
4175 			(*stat)->trtype = SPDK_NVME_TRANSPORT_RDMA;
4176 
4177 			rgroup = SPDK_CONTAINEROF(tgroup, struct spdk_nvmf_rdma_poll_group, group);
4178 			/* Count devices to allocate enough memory */
4179 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4180 				++num_devices;
4181 			}
4182 			(*stat)->rdma.devices = calloc(num_devices, sizeof(struct spdk_nvmf_rdma_device_stat));
4183 			if (!(*stat)->rdma.devices) {
4184 				SPDK_ERRLOG("Failed to allocate NVMf RDMA devices statistics\n");
4185 				free(*stat);
4186 				return -ENOMEM;
4187 			}
4188 
4189 			(*stat)->rdma.pending_data_buffer = rgroup->stat.pending_data_buffer;
4190 			(*stat)->rdma.num_devices = num_devices;
4191 			num_devices = 0;
4192 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4193 				device_stat = &(*stat)->rdma.devices[num_devices++];
4194 				device_stat->name = ibv_get_device_name(rpoller->device->context->device);
4195 				device_stat->polls = rpoller->stat.polls;
4196 				device_stat->completions = rpoller->stat.completions;
4197 				device_stat->requests = rpoller->stat.requests;
4198 				device_stat->request_latency = rpoller->stat.request_latency;
4199 				device_stat->pending_free_request = rpoller->stat.pending_free_request;
4200 				device_stat->pending_rdma_read = rpoller->stat.pending_rdma_read;
4201 				device_stat->pending_rdma_write = rpoller->stat.pending_rdma_write;
4202 			}
4203 			return 0;
4204 		}
4205 	}
4206 	return -ENOENT;
4207 }
4208 
4209 static void
4210 nvmf_rdma_poll_group_free_stat(struct spdk_nvmf_transport_poll_group_stat *stat)
4211 {
4212 	if (stat) {
4213 		free(stat->rdma.devices);
4214 	}
4215 	free(stat);
4216 }
4217 
4218 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
4219 	.name = "RDMA",
4220 	.type = SPDK_NVME_TRANSPORT_RDMA,
4221 	.opts_init = nvmf_rdma_opts_init,
4222 	.create = nvmf_rdma_create,
4223 	.dump_opts = nvmf_rdma_dump_opts,
4224 	.destroy = nvmf_rdma_destroy,
4225 
4226 	.listen = nvmf_rdma_listen,
4227 	.stop_listen = nvmf_rdma_stop_listen,
4228 	.accept = nvmf_rdma_accept,
4229 	.cdata_init = nvmf_rdma_cdata_init,
4230 
4231 	.listener_discover = nvmf_rdma_discover,
4232 
4233 	.poll_group_create = nvmf_rdma_poll_group_create,
4234 	.get_optimal_poll_group = nvmf_rdma_get_optimal_poll_group,
4235 	.poll_group_destroy = nvmf_rdma_poll_group_destroy,
4236 	.poll_group_add = nvmf_rdma_poll_group_add,
4237 	.poll_group_remove = nvmf_rdma_poll_group_remove,
4238 	.poll_group_poll = nvmf_rdma_poll_group_poll,
4239 
4240 	.req_free = nvmf_rdma_request_free,
4241 	.req_complete = nvmf_rdma_request_complete,
4242 
4243 	.qpair_fini = nvmf_rdma_close_qpair,
4244 	.qpair_get_peer_trid = nvmf_rdma_qpair_get_peer_trid,
4245 	.qpair_get_local_trid = nvmf_rdma_qpair_get_local_trid,
4246 	.qpair_get_listen_trid = nvmf_rdma_qpair_get_listen_trid,
4247 	.qpair_abort_request = nvmf_rdma_qpair_abort_request,
4248 
4249 	.poll_group_get_stat = nvmf_rdma_poll_group_get_stat,
4250 	.poll_group_free_stat = nvmf_rdma_poll_group_free_stat,
4251 };
4252 
4253 SPDK_NVMF_TRANSPORT_REGISTER(rdma, &spdk_nvmf_transport_rdma);
4254 SPDK_LOG_REGISTER_COMPONENT(rdma)
4255