xref: /spdk/lib/nvmf/rdma.c (revision 4e8e97c886e47e337dc470ac8c1ffa044d729af0)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2019, 2020 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 static int g_spdk_nvmf_ibv_query_mask =
65 	IBV_QP_STATE |
66 	IBV_QP_PKEY_INDEX |
67 	IBV_QP_PORT |
68 	IBV_QP_ACCESS_FLAGS |
69 	IBV_QP_AV |
70 	IBV_QP_PATH_MTU |
71 	IBV_QP_DEST_QPN |
72 	IBV_QP_RQ_PSN |
73 	IBV_QP_MAX_DEST_RD_ATOMIC |
74 	IBV_QP_MIN_RNR_TIMER |
75 	IBV_QP_SQ_PSN |
76 	IBV_QP_TIMEOUT |
77 	IBV_QP_RETRY_CNT |
78 	IBV_QP_RNR_RETRY |
79 	IBV_QP_MAX_QP_RD_ATOMIC;
80 
81 enum spdk_nvmf_rdma_request_state {
82 	/* The request is not currently in use */
83 	RDMA_REQUEST_STATE_FREE = 0,
84 
85 	/* Initial state when request first received */
86 	RDMA_REQUEST_STATE_NEW,
87 
88 	/* The request is queued until a data buffer is available. */
89 	RDMA_REQUEST_STATE_NEED_BUFFER,
90 
91 	/* The request is waiting on RDMA queue depth availability
92 	 * to transfer data from the host to the controller.
93 	 */
94 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
95 
96 	/* The request is currently transferring data from the host to the controller. */
97 	RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
98 
99 	/* The request is ready to execute at the block device */
100 	RDMA_REQUEST_STATE_READY_TO_EXECUTE,
101 
102 	/* The request is currently executing at the block device */
103 	RDMA_REQUEST_STATE_EXECUTING,
104 
105 	/* The request finished executing at the block device */
106 	RDMA_REQUEST_STATE_EXECUTED,
107 
108 	/* The request is waiting on RDMA queue depth availability
109 	 * to transfer data from the controller to the host.
110 	 */
111 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
112 
113 	/* The request is ready to send a completion */
114 	RDMA_REQUEST_STATE_READY_TO_COMPLETE,
115 
116 	/* The request is currently transferring data from the controller to the host. */
117 	RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
118 
119 	/* The request currently has an outstanding completion without an
120 	 * associated data transfer.
121 	 */
122 	RDMA_REQUEST_STATE_COMPLETING,
123 
124 	/* The request completed and can be marked free. */
125 	RDMA_REQUEST_STATE_COMPLETED,
126 
127 	/* Terminator */
128 	RDMA_REQUEST_NUM_STATES,
129 };
130 
131 #define OBJECT_NVMF_RDMA_IO				0x40
132 
133 #define TRACE_GROUP_NVMF_RDMA				0x4
134 #define TRACE_RDMA_REQUEST_STATE_NEW					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x0)
135 #define TRACE_RDMA_REQUEST_STATE_NEED_BUFFER				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x1)
136 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x2)
137 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x3)
138 #define TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x4)
139 #define TRACE_RDMA_REQUEST_STATE_EXECUTING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x5)
140 #define TRACE_RDMA_REQUEST_STATE_EXECUTED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x6)
141 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING		SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x7)
142 #define TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x8)
143 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x9)
144 #define TRACE_RDMA_REQUEST_STATE_COMPLETING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xA)
145 #define TRACE_RDMA_REQUEST_STATE_COMPLETED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xB)
146 #define TRACE_RDMA_QP_CREATE						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xC)
147 #define TRACE_RDMA_IBV_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xD)
148 #define TRACE_RDMA_CM_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xE)
149 #define TRACE_RDMA_QP_STATE_CHANGE					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xF)
150 #define TRACE_RDMA_QP_DISCONNECT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x10)
151 #define TRACE_RDMA_QP_DESTROY						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x11)
152 
153 SPDK_TRACE_REGISTER_FN(nvmf_trace, "nvmf_rdma", TRACE_GROUP_NVMF_RDMA)
154 {
155 	spdk_trace_register_object(OBJECT_NVMF_RDMA_IO, 'r');
156 	spdk_trace_register_description("RDMA_REQ_NEW", TRACE_RDMA_REQUEST_STATE_NEW,
157 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 1, 1, "cmid:   ");
158 	spdk_trace_register_description("RDMA_REQ_NEED_BUFFER", TRACE_RDMA_REQUEST_STATE_NEED_BUFFER,
159 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
160 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_C2H",
161 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
162 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
163 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_H2C",
164 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
165 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
166 	spdk_trace_register_description("RDMA_REQ_TX_H2C",
167 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
168 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
169 	spdk_trace_register_description("RDMA_REQ_RDY_TO_EXECUTE",
170 					TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE,
171 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
172 	spdk_trace_register_description("RDMA_REQ_EXECUTING",
173 					TRACE_RDMA_REQUEST_STATE_EXECUTING,
174 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
175 	spdk_trace_register_description("RDMA_REQ_EXECUTED",
176 					TRACE_RDMA_REQUEST_STATE_EXECUTED,
177 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
178 	spdk_trace_register_description("RDMA_REQ_RDY_TO_COMPL",
179 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE,
180 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
181 	spdk_trace_register_description("RDMA_REQ_COMPLETING_C2H",
182 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
183 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
184 	spdk_trace_register_description("RDMA_REQ_COMPLETING",
185 					TRACE_RDMA_REQUEST_STATE_COMPLETING,
186 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
187 	spdk_trace_register_description("RDMA_REQ_COMPLETED",
188 					TRACE_RDMA_REQUEST_STATE_COMPLETED,
189 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
190 
191 	spdk_trace_register_description("RDMA_QP_CREATE", TRACE_RDMA_QP_CREATE,
192 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
193 	spdk_trace_register_description("RDMA_IBV_ASYNC_EVENT", TRACE_RDMA_IBV_ASYNC_EVENT,
194 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
195 	spdk_trace_register_description("RDMA_CM_ASYNC_EVENT", TRACE_RDMA_CM_ASYNC_EVENT,
196 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
197 	spdk_trace_register_description("RDMA_QP_STATE_CHANGE", TRACE_RDMA_QP_STATE_CHANGE,
198 					OWNER_NONE, OBJECT_NONE, 0, 1, "state:  ");
199 	spdk_trace_register_description("RDMA_QP_DISCONNECT", TRACE_RDMA_QP_DISCONNECT,
200 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
201 	spdk_trace_register_description("RDMA_QP_DESTROY", TRACE_RDMA_QP_DESTROY,
202 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
203 }
204 
205 enum spdk_nvmf_rdma_wr_type {
206 	RDMA_WR_TYPE_RECV,
207 	RDMA_WR_TYPE_SEND,
208 	RDMA_WR_TYPE_DATA,
209 };
210 
211 struct spdk_nvmf_rdma_wr {
212 	enum spdk_nvmf_rdma_wr_type	type;
213 };
214 
215 /* This structure holds commands as they are received off the wire.
216  * It must be dynamically paired with a full request object
217  * (spdk_nvmf_rdma_request) to service a request. It is separate
218  * from the request because RDMA does not appear to order
219  * completions, so occasionally we'll get a new incoming
220  * command when there aren't any free request objects.
221  */
222 struct spdk_nvmf_rdma_recv {
223 	struct ibv_recv_wr			wr;
224 	struct ibv_sge				sgl[NVMF_DEFAULT_RX_SGE];
225 
226 	struct spdk_nvmf_rdma_qpair		*qpair;
227 
228 	/* In-capsule data buffer */
229 	uint8_t					*buf;
230 
231 	struct spdk_nvmf_rdma_wr		rdma_wr;
232 	uint64_t				receive_tsc;
233 
234 	STAILQ_ENTRY(spdk_nvmf_rdma_recv)	link;
235 };
236 
237 struct spdk_nvmf_rdma_request_data {
238 	struct spdk_nvmf_rdma_wr	rdma_wr;
239 	struct ibv_send_wr		wr;
240 	struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
241 };
242 
243 struct spdk_nvmf_rdma_request {
244 	struct spdk_nvmf_request		req;
245 
246 	enum spdk_nvmf_rdma_request_state	state;
247 
248 	struct spdk_nvmf_rdma_recv		*recv;
249 
250 	struct {
251 		struct spdk_nvmf_rdma_wr	rdma_wr;
252 		struct	ibv_send_wr		wr;
253 		struct	ibv_sge			sgl[NVMF_DEFAULT_RSP_SGE];
254 	} rsp;
255 
256 	struct spdk_nvmf_rdma_request_data	data;
257 
258 	uint32_t				iovpos;
259 
260 	uint32_t				num_outstanding_data_wr;
261 	uint64_t				receive_tsc;
262 
263 	STAILQ_ENTRY(spdk_nvmf_rdma_request)	state_link;
264 };
265 
266 struct spdk_nvmf_rdma_resource_opts {
267 	struct spdk_nvmf_rdma_qpair	*qpair;
268 	/* qp points either to an ibv_qp object or an ibv_srq object depending on the value of shared. */
269 	void				*qp;
270 	struct ibv_pd			*pd;
271 	uint32_t			max_queue_depth;
272 	uint32_t			in_capsule_data_size;
273 	bool				shared;
274 };
275 
276 struct spdk_nvmf_recv_wr_list {
277 	struct ibv_recv_wr	*first;
278 	struct ibv_recv_wr	*last;
279 };
280 
281 struct spdk_nvmf_rdma_resources {
282 	/* Array of size "max_queue_depth" containing RDMA requests. */
283 	struct spdk_nvmf_rdma_request		*reqs;
284 
285 	/* Array of size "max_queue_depth" containing RDMA recvs. */
286 	struct spdk_nvmf_rdma_recv		*recvs;
287 
288 	/* Array of size "max_queue_depth" containing 64 byte capsules
289 	 * used for receive.
290 	 */
291 	union nvmf_h2c_msg			*cmds;
292 	struct ibv_mr				*cmds_mr;
293 
294 	/* Array of size "max_queue_depth" containing 16 byte completions
295 	 * to be sent back to the user.
296 	 */
297 	union nvmf_c2h_msg			*cpls;
298 	struct ibv_mr				*cpls_mr;
299 
300 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
301 	 * buffers to be used for in capsule data.
302 	 */
303 	void					*bufs;
304 	struct ibv_mr				*bufs_mr;
305 
306 	/* The list of pending recvs to transfer */
307 	struct spdk_nvmf_recv_wr_list		recvs_to_post;
308 
309 	/* Receives that are waiting for a request object */
310 	STAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
311 
312 	/* Queue to track free requests */
313 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	free_queue;
314 };
315 
316 typedef void (*spdk_nvmf_rdma_qpair_ibv_event)(struct spdk_nvmf_rdma_qpair *rqpair);
317 
318 struct spdk_nvmf_rdma_ibv_event_ctx {
319 	struct spdk_nvmf_rdma_qpair			*rqpair;
320 	spdk_nvmf_rdma_qpair_ibv_event			cb_fn;
321 	/* Link to other ibv events associated with this qpair */
322 	STAILQ_ENTRY(spdk_nvmf_rdma_ibv_event_ctx)	link;
323 };
324 
325 struct spdk_nvmf_rdma_qpair {
326 	struct spdk_nvmf_qpair			qpair;
327 
328 	struct spdk_nvmf_rdma_device		*device;
329 	struct spdk_nvmf_rdma_poller		*poller;
330 
331 	struct spdk_rdma_qp			*rdma_qp;
332 	struct rdma_cm_id			*cm_id;
333 	struct ibv_srq				*srq;
334 	struct rdma_cm_id			*listen_id;
335 
336 	/* The maximum number of I/O outstanding on this connection at one time */
337 	uint16_t				max_queue_depth;
338 
339 	/* The maximum number of active RDMA READ and ATOMIC operations at one time */
340 	uint16_t				max_read_depth;
341 
342 	/* The maximum number of RDMA SEND operations at one time */
343 	uint32_t				max_send_depth;
344 
345 	/* The current number of outstanding WRs from this qpair's
346 	 * recv queue. Should not exceed device->attr.max_queue_depth.
347 	 */
348 	uint16_t				current_recv_depth;
349 
350 	/* The current number of active RDMA READ operations */
351 	uint16_t				current_read_depth;
352 
353 	/* The current number of posted WRs from this qpair's
354 	 * send queue. Should not exceed max_send_depth.
355 	 */
356 	uint32_t				current_send_depth;
357 
358 	/* The maximum number of SGEs per WR on the send queue */
359 	uint32_t				max_send_sge;
360 
361 	/* The maximum number of SGEs per WR on the recv queue */
362 	uint32_t				max_recv_sge;
363 
364 	struct spdk_nvmf_rdma_resources		*resources;
365 
366 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_read_queue;
367 
368 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_write_queue;
369 
370 	/* Number of requests not in the free state */
371 	uint32_t				qd;
372 
373 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	link;
374 
375 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	recv_link;
376 
377 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	send_link;
378 
379 	/* IBV queue pair attributes: they are used to manage
380 	 * qp state and recover from errors.
381 	 */
382 	enum ibv_qp_state			ibv_state;
383 
384 	/*
385 	 * io_channel which is used to destroy qpair when it is removed from poll group
386 	 */
387 	struct spdk_io_channel		*destruct_channel;
388 
389 	/* List of ibv async events */
390 	STAILQ_HEAD(, spdk_nvmf_rdma_ibv_event_ctx)	ibv_events;
391 
392 	/* Lets us know that we have received the last_wqe event. */
393 	bool					last_wqe_reached;
394 
395 	/* Indicate that nvmf_rdma_close_qpair is called */
396 	bool					to_close;
397 };
398 
399 struct spdk_nvmf_rdma_poller_stat {
400 	uint64_t				completions;
401 	uint64_t				polls;
402 	uint64_t				requests;
403 	uint64_t				request_latency;
404 	uint64_t				pending_free_request;
405 	uint64_t				pending_rdma_read;
406 	uint64_t				pending_rdma_write;
407 };
408 
409 struct spdk_nvmf_rdma_poller {
410 	struct spdk_nvmf_rdma_device		*device;
411 	struct spdk_nvmf_rdma_poll_group	*group;
412 
413 	int					num_cqe;
414 	int					required_num_wr;
415 	struct ibv_cq				*cq;
416 
417 	/* The maximum number of I/O outstanding on the shared receive queue at one time */
418 	uint16_t				max_srq_depth;
419 
420 	/* Shared receive queue */
421 	struct ibv_srq				*srq;
422 
423 	struct spdk_nvmf_rdma_resources		*resources;
424 	struct spdk_nvmf_rdma_poller_stat	stat;
425 
426 	TAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs;
427 
428 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_recv;
429 
430 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_send;
431 
432 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
433 };
434 
435 struct spdk_nvmf_rdma_poll_group_stat {
436 	uint64_t				pending_data_buffer;
437 };
438 
439 struct spdk_nvmf_rdma_poll_group {
440 	struct spdk_nvmf_transport_poll_group		group;
441 	struct spdk_nvmf_rdma_poll_group_stat		stat;
442 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)		pollers;
443 	TAILQ_ENTRY(spdk_nvmf_rdma_poll_group)		link;
444 	/*
445 	 * buffers which are split across multiple RDMA
446 	 * memory regions cannot be used by this transport.
447 	 */
448 	STAILQ_HEAD(, spdk_nvmf_transport_pg_cache_buf)	retired_bufs;
449 };
450 
451 struct spdk_nvmf_rdma_conn_sched {
452 	struct spdk_nvmf_rdma_poll_group *next_admin_pg;
453 	struct spdk_nvmf_rdma_poll_group *next_io_pg;
454 };
455 
456 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
457 struct spdk_nvmf_rdma_device {
458 	struct ibv_device_attr			attr;
459 	struct ibv_context			*context;
460 
461 	struct spdk_mem_map			*map;
462 	struct ibv_pd				*pd;
463 
464 	int					num_srq;
465 
466 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
467 };
468 
469 struct spdk_nvmf_rdma_port {
470 	const struct spdk_nvme_transport_id	*trid;
471 	struct rdma_cm_id			*id;
472 	struct spdk_nvmf_rdma_device		*device;
473 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
474 };
475 
476 struct spdk_nvmf_rdma_transport {
477 	struct spdk_nvmf_transport	transport;
478 
479 	struct spdk_nvmf_rdma_conn_sched conn_sched;
480 
481 	struct rdma_event_channel	*event_channel;
482 
483 	struct spdk_mempool		*data_wr_pool;
484 
485 	pthread_mutex_t			lock;
486 
487 	/* fields used to poll RDMA/IB events */
488 	nfds_t			npoll_fds;
489 	struct pollfd		*poll_fds;
490 
491 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
492 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
493 	TAILQ_HEAD(, spdk_nvmf_rdma_poll_group)	poll_groups;
494 };
495 
496 static bool
497 nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
498 			  struct spdk_nvmf_rdma_request *rdma_req);
499 
500 static inline int
501 nvmf_rdma_check_ibv_state(enum ibv_qp_state state)
502 {
503 	switch (state) {
504 	case IBV_QPS_RESET:
505 	case IBV_QPS_INIT:
506 	case IBV_QPS_RTR:
507 	case IBV_QPS_RTS:
508 	case IBV_QPS_SQD:
509 	case IBV_QPS_SQE:
510 	case IBV_QPS_ERR:
511 		return 0;
512 	default:
513 		return -1;
514 	}
515 }
516 
517 static inline enum spdk_nvme_media_error_status_code
518 nvmf_rdma_dif_error_to_compl_status(uint8_t err_type) {
519 	enum spdk_nvme_media_error_status_code result;
520 	switch (err_type)
521 	{
522 	case SPDK_DIF_REFTAG_ERROR:
523 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
524 		break;
525 	case SPDK_DIF_APPTAG_ERROR:
526 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
527 		break;
528 	case SPDK_DIF_GUARD_ERROR:
529 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
530 		break;
531 	default:
532 		SPDK_UNREACHABLE();
533 	}
534 
535 	return result;
536 }
537 
538 static enum ibv_qp_state
539 nvmf_rdma_update_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair) {
540 	enum ibv_qp_state old_state, new_state;
541 	struct ibv_qp_attr qp_attr;
542 	struct ibv_qp_init_attr init_attr;
543 	int rc;
544 
545 	old_state = rqpair->ibv_state;
546 	rc = ibv_query_qp(rqpair->rdma_qp->qp, &qp_attr,
547 			  g_spdk_nvmf_ibv_query_mask, &init_attr);
548 
549 	if (rc)
550 	{
551 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
552 		return IBV_QPS_ERR + 1;
553 	}
554 
555 	new_state = qp_attr.qp_state;
556 	rqpair->ibv_state = new_state;
557 	qp_attr.ah_attr.port_num = qp_attr.port_num;
558 
559 	rc = nvmf_rdma_check_ibv_state(new_state);
560 	if (rc)
561 	{
562 		SPDK_ERRLOG("QP#%d: bad state updated: %u, maybe hardware issue\n", rqpair->qpair.qid, new_state);
563 		/*
564 		 * IBV_QPS_UNKNOWN undefined if lib version smaller than libibverbs-1.1.8
565 		 * IBV_QPS_UNKNOWN is the enum element after IBV_QPS_ERR
566 		 */
567 		return IBV_QPS_ERR + 1;
568 	}
569 
570 	if (old_state != new_state)
571 	{
572 		spdk_trace_record(TRACE_RDMA_QP_STATE_CHANGE, 0, 0,
573 				  (uintptr_t)rqpair->cm_id, new_state);
574 	}
575 	return new_state;
576 }
577 
578 static void
579 nvmf_rdma_request_free_data(struct spdk_nvmf_rdma_request *rdma_req,
580 			    struct spdk_nvmf_rdma_transport *rtransport)
581 {
582 	struct spdk_nvmf_rdma_request_data	*data_wr;
583 	struct ibv_send_wr			*next_send_wr;
584 	uint64_t				req_wrid;
585 
586 	rdma_req->num_outstanding_data_wr = 0;
587 	data_wr = &rdma_req->data;
588 	req_wrid = data_wr->wr.wr_id;
589 	while (data_wr && data_wr->wr.wr_id == req_wrid) {
590 		memset(data_wr->sgl, 0, sizeof(data_wr->wr.sg_list[0]) * data_wr->wr.num_sge);
591 		data_wr->wr.num_sge = 0;
592 		next_send_wr = data_wr->wr.next;
593 		if (data_wr != &rdma_req->data) {
594 			spdk_mempool_put(rtransport->data_wr_pool, data_wr);
595 		}
596 		data_wr = (!next_send_wr || next_send_wr == &rdma_req->rsp.wr) ? NULL :
597 			  SPDK_CONTAINEROF(next_send_wr, struct spdk_nvmf_rdma_request_data, wr);
598 	}
599 }
600 
601 static void
602 nvmf_rdma_dump_request(struct spdk_nvmf_rdma_request *req)
603 {
604 	SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", req->req.data_from_pool);
605 	if (req->req.cmd) {
606 		SPDK_ERRLOG("\t\tRequest opcode: %d\n", req->req.cmd->nvmf_cmd.opcode);
607 	}
608 	if (req->recv) {
609 		SPDK_ERRLOG("\t\tRequest recv wr_id%lu\n", req->recv->wr.wr_id);
610 	}
611 }
612 
613 static void
614 nvmf_rdma_dump_qpair_contents(struct spdk_nvmf_rdma_qpair *rqpair)
615 {
616 	int i;
617 
618 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", rqpair->qpair.qid);
619 	for (i = 0; i < rqpair->max_queue_depth; i++) {
620 		if (rqpair->resources->reqs[i].state != RDMA_REQUEST_STATE_FREE) {
621 			nvmf_rdma_dump_request(&rqpair->resources->reqs[i]);
622 		}
623 	}
624 }
625 
626 static void
627 nvmf_rdma_resources_destroy(struct spdk_nvmf_rdma_resources *resources)
628 {
629 	if (resources->cmds_mr) {
630 		ibv_dereg_mr(resources->cmds_mr);
631 	}
632 
633 	if (resources->cpls_mr) {
634 		ibv_dereg_mr(resources->cpls_mr);
635 	}
636 
637 	if (resources->bufs_mr) {
638 		ibv_dereg_mr(resources->bufs_mr);
639 	}
640 
641 	spdk_free(resources->cmds);
642 	spdk_free(resources->cpls);
643 	spdk_free(resources->bufs);
644 	free(resources->reqs);
645 	free(resources->recvs);
646 	free(resources);
647 }
648 
649 
650 static struct spdk_nvmf_rdma_resources *
651 nvmf_rdma_resources_create(struct spdk_nvmf_rdma_resource_opts *opts)
652 {
653 	struct spdk_nvmf_rdma_resources	*resources;
654 	struct spdk_nvmf_rdma_request	*rdma_req;
655 	struct spdk_nvmf_rdma_recv	*rdma_recv;
656 	struct ibv_qp			*qp;
657 	struct ibv_srq			*srq;
658 	uint32_t			i;
659 	int				rc;
660 
661 	resources = calloc(1, sizeof(struct spdk_nvmf_rdma_resources));
662 	if (!resources) {
663 		SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
664 		return NULL;
665 	}
666 
667 	resources->reqs = calloc(opts->max_queue_depth, sizeof(*resources->reqs));
668 	resources->recvs = calloc(opts->max_queue_depth, sizeof(*resources->recvs));
669 	resources->cmds = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cmds),
670 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
671 	resources->cpls = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cpls),
672 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
673 
674 	if (opts->in_capsule_data_size > 0) {
675 		resources->bufs = spdk_zmalloc(opts->max_queue_depth * opts->in_capsule_data_size,
676 					       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY,
677 					       SPDK_MALLOC_DMA);
678 	}
679 
680 	if (!resources->reqs || !resources->recvs || !resources->cmds ||
681 	    !resources->cpls || (opts->in_capsule_data_size && !resources->bufs)) {
682 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
683 		goto cleanup;
684 	}
685 
686 	resources->cmds_mr = ibv_reg_mr(opts->pd, resources->cmds,
687 					opts->max_queue_depth * sizeof(*resources->cmds),
688 					IBV_ACCESS_LOCAL_WRITE);
689 	resources->cpls_mr = ibv_reg_mr(opts->pd, resources->cpls,
690 					opts->max_queue_depth * sizeof(*resources->cpls),
691 					0);
692 
693 	if (opts->in_capsule_data_size) {
694 		resources->bufs_mr = ibv_reg_mr(opts->pd, resources->bufs,
695 						opts->max_queue_depth *
696 						opts->in_capsule_data_size,
697 						IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
698 	}
699 
700 	if (!resources->cmds_mr || !resources->cpls_mr ||
701 	    (opts->in_capsule_data_size &&
702 	     !resources->bufs_mr)) {
703 		goto cleanup;
704 	}
705 	SPDK_DEBUGLOG(rdma, "Command Array: %p Length: %lx LKey: %x\n",
706 		      resources->cmds, opts->max_queue_depth * sizeof(*resources->cmds),
707 		      resources->cmds_mr->lkey);
708 	SPDK_DEBUGLOG(rdma, "Completion Array: %p Length: %lx LKey: %x\n",
709 		      resources->cpls, opts->max_queue_depth * sizeof(*resources->cpls),
710 		      resources->cpls_mr->lkey);
711 	if (resources->bufs && resources->bufs_mr) {
712 		SPDK_DEBUGLOG(rdma, "In Capsule Data Array: %p Length: %x LKey: %x\n",
713 			      resources->bufs, opts->max_queue_depth *
714 			      opts->in_capsule_data_size, resources->bufs_mr->lkey);
715 	}
716 
717 	/* Initialize queues */
718 	STAILQ_INIT(&resources->incoming_queue);
719 	STAILQ_INIT(&resources->free_queue);
720 
721 	for (i = 0; i < opts->max_queue_depth; i++) {
722 		struct ibv_recv_wr *bad_wr = NULL;
723 
724 		rdma_recv = &resources->recvs[i];
725 		rdma_recv->qpair = opts->qpair;
726 
727 		/* Set up memory to receive commands */
728 		if (resources->bufs) {
729 			rdma_recv->buf = (void *)((uintptr_t)resources->bufs + (i *
730 						  opts->in_capsule_data_size));
731 		}
732 
733 		rdma_recv->rdma_wr.type = RDMA_WR_TYPE_RECV;
734 
735 		rdma_recv->sgl[0].addr = (uintptr_t)&resources->cmds[i];
736 		rdma_recv->sgl[0].length = sizeof(resources->cmds[i]);
737 		rdma_recv->sgl[0].lkey = resources->cmds_mr->lkey;
738 		rdma_recv->wr.num_sge = 1;
739 
740 		if (rdma_recv->buf && resources->bufs_mr) {
741 			rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
742 			rdma_recv->sgl[1].length = opts->in_capsule_data_size;
743 			rdma_recv->sgl[1].lkey = resources->bufs_mr->lkey;
744 			rdma_recv->wr.num_sge++;
745 		}
746 
747 		rdma_recv->wr.wr_id = (uintptr_t)&rdma_recv->rdma_wr;
748 		rdma_recv->wr.sg_list = rdma_recv->sgl;
749 		if (opts->shared) {
750 			srq = (struct ibv_srq *)opts->qp;
751 			rc = ibv_post_srq_recv(srq, &rdma_recv->wr, &bad_wr);
752 		} else {
753 			qp = (struct ibv_qp *)opts->qp;
754 			rc = ibv_post_recv(qp, &rdma_recv->wr, &bad_wr);
755 		}
756 		if (rc) {
757 			goto cleanup;
758 		}
759 	}
760 
761 	for (i = 0; i < opts->max_queue_depth; i++) {
762 		rdma_req = &resources->reqs[i];
763 
764 		if (opts->qpair != NULL) {
765 			rdma_req->req.qpair = &opts->qpair->qpair;
766 		} else {
767 			rdma_req->req.qpair = NULL;
768 		}
769 		rdma_req->req.cmd = NULL;
770 
771 		/* Set up memory to send responses */
772 		rdma_req->req.rsp = &resources->cpls[i];
773 
774 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&resources->cpls[i];
775 		rdma_req->rsp.sgl[0].length = sizeof(resources->cpls[i]);
776 		rdma_req->rsp.sgl[0].lkey = resources->cpls_mr->lkey;
777 
778 		rdma_req->rsp.rdma_wr.type = RDMA_WR_TYPE_SEND;
779 		rdma_req->rsp.wr.wr_id = (uintptr_t)&rdma_req->rsp.rdma_wr;
780 		rdma_req->rsp.wr.next = NULL;
781 		rdma_req->rsp.wr.opcode = IBV_WR_SEND;
782 		rdma_req->rsp.wr.send_flags = IBV_SEND_SIGNALED;
783 		rdma_req->rsp.wr.sg_list = rdma_req->rsp.sgl;
784 		rdma_req->rsp.wr.num_sge = SPDK_COUNTOF(rdma_req->rsp.sgl);
785 
786 		/* Set up memory for data buffers */
787 		rdma_req->data.rdma_wr.type = RDMA_WR_TYPE_DATA;
788 		rdma_req->data.wr.wr_id = (uintptr_t)&rdma_req->data.rdma_wr;
789 		rdma_req->data.wr.next = NULL;
790 		rdma_req->data.wr.send_flags = IBV_SEND_SIGNALED;
791 		rdma_req->data.wr.sg_list = rdma_req->data.sgl;
792 		rdma_req->data.wr.num_sge = SPDK_COUNTOF(rdma_req->data.sgl);
793 
794 		/* Initialize request state to FREE */
795 		rdma_req->state = RDMA_REQUEST_STATE_FREE;
796 		STAILQ_INSERT_TAIL(&resources->free_queue, rdma_req, state_link);
797 	}
798 
799 	return resources;
800 
801 cleanup:
802 	nvmf_rdma_resources_destroy(resources);
803 	return NULL;
804 }
805 
806 static void
807 nvmf_rdma_qpair_clean_ibv_events(struct spdk_nvmf_rdma_qpair *rqpair)
808 {
809 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx, *tctx;
810 	STAILQ_FOREACH_SAFE(ctx, &rqpair->ibv_events, link, tctx) {
811 		ctx->rqpair = NULL;
812 		/* Memory allocated for ctx is freed in nvmf_rdma_qpair_process_ibv_event */
813 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
814 	}
815 }
816 
817 static void
818 nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
819 {
820 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
821 	struct ibv_recv_wr		*bad_recv_wr = NULL;
822 	int				rc;
823 
824 	spdk_trace_record(TRACE_RDMA_QP_DESTROY, 0, 0, (uintptr_t)rqpair->cm_id, 0);
825 
826 	if (rqpair->qd != 0) {
827 		struct spdk_nvmf_qpair *qpair = &rqpair->qpair;
828 		struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(qpair->transport,
829 				struct spdk_nvmf_rdma_transport, transport);
830 		struct spdk_nvmf_rdma_request *req;
831 		uint32_t i, max_req_count = 0;
832 
833 		SPDK_WARNLOG("Destroying qpair when queue depth is %d\n", rqpair->qd);
834 
835 		if (rqpair->srq == NULL) {
836 			nvmf_rdma_dump_qpair_contents(rqpair);
837 			max_req_count = rqpair->max_queue_depth;
838 		} else if (rqpair->poller && rqpair->resources) {
839 			max_req_count = rqpair->poller->max_srq_depth;
840 		}
841 
842 		SPDK_DEBUGLOG(rdma, "Release incomplete requests\n");
843 		for (i = 0; i < max_req_count; i++) {
844 			req = &rqpair->resources->reqs[i];
845 			if (req->req.qpair == qpair && req->state != RDMA_REQUEST_STATE_FREE) {
846 				/* nvmf_rdma_request_process checks qpair ibv and internal state
847 				 * and completes a request */
848 				nvmf_rdma_request_process(rtransport, req);
849 			}
850 		}
851 		assert(rqpair->qd == 0);
852 	}
853 
854 	if (rqpair->poller) {
855 		TAILQ_REMOVE(&rqpair->poller->qpairs, rqpair, link);
856 
857 		if (rqpair->srq != NULL && rqpair->resources != NULL) {
858 			/* Drop all received but unprocessed commands for this queue and return them to SRQ */
859 			STAILQ_FOREACH_SAFE(rdma_recv, &rqpair->resources->incoming_queue, link, recv_tmp) {
860 				if (rqpair == rdma_recv->qpair) {
861 					STAILQ_REMOVE(&rqpair->resources->incoming_queue, rdma_recv, spdk_nvmf_rdma_recv, link);
862 					rc = ibv_post_srq_recv(rqpair->srq, &rdma_recv->wr, &bad_recv_wr);
863 					if (rc) {
864 						SPDK_ERRLOG("Unable to re-post rx descriptor\n");
865 					}
866 				}
867 			}
868 		}
869 	}
870 
871 	if (rqpair->cm_id) {
872 		if (rqpair->rdma_qp != NULL) {
873 			spdk_rdma_qp_destroy(rqpair->rdma_qp);
874 			rqpair->rdma_qp = NULL;
875 		}
876 		rdma_destroy_id(rqpair->cm_id);
877 
878 		if (rqpair->poller != NULL && rqpair->srq == NULL) {
879 			rqpair->poller->required_num_wr -= MAX_WR_PER_QP(rqpair->max_queue_depth);
880 		}
881 	}
882 
883 	if (rqpair->srq == NULL && rqpair->resources != NULL) {
884 		nvmf_rdma_resources_destroy(rqpair->resources);
885 	}
886 
887 	nvmf_rdma_qpair_clean_ibv_events(rqpair);
888 
889 	if (rqpair->destruct_channel) {
890 		spdk_put_io_channel(rqpair->destruct_channel);
891 		rqpair->destruct_channel = NULL;
892 	}
893 
894 	free(rqpair);
895 }
896 
897 static int
898 nvmf_rdma_resize_cq(struct spdk_nvmf_rdma_qpair *rqpair, struct spdk_nvmf_rdma_device *device)
899 {
900 	struct spdk_nvmf_rdma_poller	*rpoller;
901 	int				rc, num_cqe, required_num_wr;
902 
903 	/* Enlarge CQ size dynamically */
904 	rpoller = rqpair->poller;
905 	required_num_wr = rpoller->required_num_wr + MAX_WR_PER_QP(rqpair->max_queue_depth);
906 	num_cqe = rpoller->num_cqe;
907 	if (num_cqe < required_num_wr) {
908 		num_cqe = spdk_max(num_cqe * 2, required_num_wr);
909 		num_cqe = spdk_min(num_cqe, device->attr.max_cqe);
910 	}
911 
912 	if (rpoller->num_cqe != num_cqe) {
913 		if (required_num_wr > device->attr.max_cqe) {
914 			SPDK_ERRLOG("RDMA CQE requirement (%d) exceeds device max_cqe limitation (%d)\n",
915 				    required_num_wr, device->attr.max_cqe);
916 			return -1;
917 		}
918 
919 		SPDK_DEBUGLOG(rdma, "Resize RDMA CQ from %d to %d\n", rpoller->num_cqe, num_cqe);
920 		rc = ibv_resize_cq(rpoller->cq, num_cqe);
921 		if (rc) {
922 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
923 			return -1;
924 		}
925 
926 		rpoller->num_cqe = num_cqe;
927 	}
928 
929 	rpoller->required_num_wr = required_num_wr;
930 	return 0;
931 }
932 
933 static int
934 nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
935 {
936 	struct spdk_nvmf_rdma_qpair		*rqpair;
937 	struct spdk_nvmf_rdma_transport		*rtransport;
938 	struct spdk_nvmf_transport		*transport;
939 	struct spdk_nvmf_rdma_resource_opts	opts;
940 	struct spdk_nvmf_rdma_device		*device;
941 	struct spdk_rdma_qp_init_attr		qp_init_attr = {};
942 
943 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
944 	device = rqpair->device;
945 
946 	qp_init_attr.qp_context	= rqpair;
947 	qp_init_attr.pd		= device->pd;
948 	qp_init_attr.send_cq	= rqpair->poller->cq;
949 	qp_init_attr.recv_cq	= rqpair->poller->cq;
950 
951 	if (rqpair->srq) {
952 		qp_init_attr.srq		= rqpair->srq;
953 	} else {
954 		qp_init_attr.cap.max_recv_wr	= rqpair->max_queue_depth;
955 	}
956 
957 	/* SEND, READ, and WRITE operations */
958 	qp_init_attr.cap.max_send_wr	= (uint32_t)rqpair->max_queue_depth * 2;
959 	qp_init_attr.cap.max_send_sge	= spdk_min((uint32_t)device->attr.max_sge, NVMF_DEFAULT_TX_SGE);
960 	qp_init_attr.cap.max_recv_sge	= spdk_min((uint32_t)device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
961 
962 	if (rqpair->srq == NULL && nvmf_rdma_resize_cq(rqpair, device) < 0) {
963 		SPDK_ERRLOG("Failed to resize the completion queue. Cannot initialize qpair.\n");
964 		goto error;
965 	}
966 
967 	rqpair->rdma_qp = spdk_rdma_qp_create(rqpair->cm_id, &qp_init_attr);
968 	if (!rqpair->rdma_qp) {
969 		goto error;
970 	}
971 
972 	rqpair->max_send_depth = spdk_min((uint32_t)(rqpair->max_queue_depth * 2),
973 					  qp_init_attr.cap.max_send_wr);
974 	rqpair->max_send_sge = spdk_min(NVMF_DEFAULT_TX_SGE, qp_init_attr.cap.max_send_sge);
975 	rqpair->max_recv_sge = spdk_min(NVMF_DEFAULT_RX_SGE, qp_init_attr.cap.max_recv_sge);
976 	spdk_trace_record(TRACE_RDMA_QP_CREATE, 0, 0, (uintptr_t)rqpair->cm_id, 0);
977 	SPDK_DEBUGLOG(rdma, "New RDMA Connection: %p\n", qpair);
978 
979 	if (rqpair->poller->srq == NULL) {
980 		rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
981 		transport = &rtransport->transport;
982 
983 		opts.qp = rqpair->rdma_qp->qp;
984 		opts.pd = rqpair->cm_id->pd;
985 		opts.qpair = rqpair;
986 		opts.shared = false;
987 		opts.max_queue_depth = rqpair->max_queue_depth;
988 		opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
989 
990 		rqpair->resources = nvmf_rdma_resources_create(&opts);
991 
992 		if (!rqpair->resources) {
993 			SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
994 			rdma_destroy_qp(rqpair->cm_id);
995 			goto error;
996 		}
997 	} else {
998 		rqpair->resources = rqpair->poller->resources;
999 	}
1000 
1001 	rqpair->current_recv_depth = 0;
1002 	STAILQ_INIT(&rqpair->pending_rdma_read_queue);
1003 	STAILQ_INIT(&rqpair->pending_rdma_write_queue);
1004 
1005 	return 0;
1006 
1007 error:
1008 	rdma_destroy_id(rqpair->cm_id);
1009 	rqpair->cm_id = NULL;
1010 	return -1;
1011 }
1012 
1013 /* Append the given recv wr structure to the resource structs outstanding recvs list. */
1014 /* This function accepts either a single wr or the first wr in a linked list. */
1015 static void
1016 nvmf_rdma_qpair_queue_recv_wrs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *first)
1017 {
1018 	struct ibv_recv_wr *last;
1019 
1020 	last = first;
1021 	while (last->next != NULL) {
1022 		last = last->next;
1023 	}
1024 
1025 	if (rqpair->resources->recvs_to_post.first == NULL) {
1026 		rqpair->resources->recvs_to_post.first = first;
1027 		rqpair->resources->recvs_to_post.last = last;
1028 		if (rqpair->srq == NULL) {
1029 			STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_recv, rqpair, recv_link);
1030 		}
1031 	} else {
1032 		rqpair->resources->recvs_to_post.last->next = first;
1033 		rqpair->resources->recvs_to_post.last = last;
1034 	}
1035 }
1036 
1037 static int
1038 request_transfer_in(struct spdk_nvmf_request *req)
1039 {
1040 	struct spdk_nvmf_rdma_request	*rdma_req;
1041 	struct spdk_nvmf_qpair		*qpair;
1042 	struct spdk_nvmf_rdma_qpair	*rqpair;
1043 
1044 	qpair = req->qpair;
1045 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1046 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1047 
1048 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
1049 	assert(rdma_req != NULL);
1050 
1051 	if (spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, &rdma_req->data.wr)) {
1052 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1053 	}
1054 
1055 	rqpair->current_read_depth += rdma_req->num_outstanding_data_wr;
1056 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr;
1057 	return 0;
1058 }
1059 
1060 static int
1061 request_transfer_out(struct spdk_nvmf_request *req, int *data_posted)
1062 {
1063 	int				num_outstanding_data_wr = 0;
1064 	struct spdk_nvmf_rdma_request	*rdma_req;
1065 	struct spdk_nvmf_qpair		*qpair;
1066 	struct spdk_nvmf_rdma_qpair	*rqpair;
1067 	struct spdk_nvme_cpl		*rsp;
1068 	struct ibv_send_wr		*first = NULL;
1069 
1070 	*data_posted = 0;
1071 	qpair = req->qpair;
1072 	rsp = &req->rsp->nvme_cpl;
1073 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1074 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1075 
1076 	/* Advance our sq_head pointer */
1077 	if (qpair->sq_head == qpair->sq_head_max) {
1078 		qpair->sq_head = 0;
1079 	} else {
1080 		qpair->sq_head++;
1081 	}
1082 	rsp->sqhd = qpair->sq_head;
1083 
1084 	/* queue the capsule for the recv buffer */
1085 	assert(rdma_req->recv != NULL);
1086 
1087 	nvmf_rdma_qpair_queue_recv_wrs(rqpair, &rdma_req->recv->wr);
1088 
1089 	rdma_req->recv = NULL;
1090 	assert(rqpair->current_recv_depth > 0);
1091 	rqpair->current_recv_depth--;
1092 
1093 	/* Build the response which consists of optional
1094 	 * RDMA WRITEs to transfer data, plus an RDMA SEND
1095 	 * containing the response.
1096 	 */
1097 	first = &rdma_req->rsp.wr;
1098 
1099 	if (rsp->status.sc != SPDK_NVME_SC_SUCCESS) {
1100 		/* On failure, data was not read from the controller. So clear the
1101 		 * number of outstanding data WRs to zero.
1102 		 */
1103 		rdma_req->num_outstanding_data_wr = 0;
1104 	} else if (req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1105 		first = &rdma_req->data.wr;
1106 		*data_posted = 1;
1107 		num_outstanding_data_wr = rdma_req->num_outstanding_data_wr;
1108 	}
1109 	if (spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, first)) {
1110 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1111 	}
1112 
1113 	/* +1 for the rsp wr */
1114 	rqpair->current_send_depth += num_outstanding_data_wr + 1;
1115 
1116 	return 0;
1117 }
1118 
1119 static int
1120 nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
1121 {
1122 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
1123 	struct rdma_conn_param				ctrlr_event_data = {};
1124 	int						rc;
1125 
1126 	accept_data.recfmt = 0;
1127 	accept_data.crqsize = rqpair->max_queue_depth;
1128 
1129 	ctrlr_event_data.private_data = &accept_data;
1130 	ctrlr_event_data.private_data_len = sizeof(accept_data);
1131 	if (id->ps == RDMA_PS_TCP) {
1132 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
1133 		ctrlr_event_data.initiator_depth = rqpair->max_read_depth;
1134 	}
1135 
1136 	/* Configure infinite retries for the initiator side qpair.
1137 	 * When using a shared receive queue on the target side,
1138 	 * we need to pass this value to the initiator to prevent the
1139 	 * initiator side NIC from completing SEND requests back to the
1140 	 * initiator with status rnr_retry_count_exceeded. */
1141 	if (rqpair->srq != NULL) {
1142 		ctrlr_event_data.rnr_retry_count = 0x7;
1143 	}
1144 
1145 	/* When qpair is created without use of rdma cm API, an additional
1146 	 * information must be provided to initiator in the connection response:
1147 	 * whether qpair is using SRQ and its qp_num
1148 	 * Fields below are ignored by rdma cm if qpair has been
1149 	 * created using rdma cm API. */
1150 	ctrlr_event_data.srq = rqpair->srq ? 1 : 0;
1151 	ctrlr_event_data.qp_num = rqpair->rdma_qp->qp->qp_num;
1152 
1153 	rc = spdk_rdma_qp_accept(rqpair->rdma_qp, &ctrlr_event_data);
1154 	if (rc) {
1155 		SPDK_ERRLOG("Error %d on spdk_rdma_qp_accept\n", errno);
1156 	} else {
1157 		SPDK_DEBUGLOG(rdma, "Sent back the accept\n");
1158 	}
1159 
1160 	return rc;
1161 }
1162 
1163 static void
1164 nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
1165 {
1166 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
1167 
1168 	rej_data.recfmt = 0;
1169 	rej_data.sts = error;
1170 
1171 	rdma_reject(id, &rej_data, sizeof(rej_data));
1172 }
1173 
1174 static int
1175 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event)
1176 {
1177 	struct spdk_nvmf_rdma_transport *rtransport;
1178 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
1179 	struct spdk_nvmf_rdma_port	*port;
1180 	struct rdma_conn_param		*rdma_param = NULL;
1181 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
1182 	uint16_t			max_queue_depth;
1183 	uint16_t			max_read_depth;
1184 
1185 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1186 
1187 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
1188 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
1189 
1190 	rdma_param = &event->param.conn;
1191 	if (rdma_param->private_data == NULL ||
1192 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1193 		SPDK_ERRLOG("connect request: no private data provided\n");
1194 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
1195 		return -1;
1196 	}
1197 
1198 	private_data = rdma_param->private_data;
1199 	if (private_data->recfmt != 0) {
1200 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
1201 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
1202 		return -1;
1203 	}
1204 
1205 	SPDK_DEBUGLOG(rdma, "Connect Recv on fabric intf name %s, dev_name %s\n",
1206 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
1207 
1208 	port = event->listen_id->context;
1209 	SPDK_DEBUGLOG(rdma, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
1210 		      event->listen_id, event->listen_id->verbs, port);
1211 
1212 	/* Figure out the supported queue depth. This is a multi-step process
1213 	 * that takes into account hardware maximums, host provided values,
1214 	 * and our target's internal memory limits */
1215 
1216 	SPDK_DEBUGLOG(rdma, "Calculating Queue Depth\n");
1217 
1218 	/* Start with the maximum queue depth allowed by the target */
1219 	max_queue_depth = rtransport->transport.opts.max_queue_depth;
1220 	max_read_depth = rtransport->transport.opts.max_queue_depth;
1221 	SPDK_DEBUGLOG(rdma, "Target Max Queue Depth: %d\n",
1222 		      rtransport->transport.opts.max_queue_depth);
1223 
1224 	/* Next check the local NIC's hardware limitations */
1225 	SPDK_DEBUGLOG(rdma,
1226 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
1227 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
1228 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
1229 	max_read_depth = spdk_min(max_read_depth, port->device->attr.max_qp_init_rd_atom);
1230 
1231 	/* Next check the remote NIC's hardware limitations */
1232 	SPDK_DEBUGLOG(rdma,
1233 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
1234 		      rdma_param->initiator_depth, rdma_param->responder_resources);
1235 	if (rdma_param->initiator_depth > 0) {
1236 		max_read_depth = spdk_min(max_read_depth, rdma_param->initiator_depth);
1237 	}
1238 
1239 	/* Finally check for the host software requested values, which are
1240 	 * optional. */
1241 	if (rdma_param->private_data != NULL &&
1242 	    rdma_param->private_data_len >= sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1243 		SPDK_DEBUGLOG(rdma, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1244 		SPDK_DEBUGLOG(rdma, "Host Send Queue Size: %d\n", private_data->hsqsize);
1245 		max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
1246 		max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
1247 	}
1248 
1249 	SPDK_DEBUGLOG(rdma, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
1250 		      max_queue_depth, max_read_depth);
1251 
1252 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
1253 	if (rqpair == NULL) {
1254 		SPDK_ERRLOG("Could not allocate new connection.\n");
1255 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1256 		return -1;
1257 	}
1258 
1259 	rqpair->device = port->device;
1260 	rqpair->max_queue_depth = max_queue_depth;
1261 	rqpair->max_read_depth = max_read_depth;
1262 	rqpair->cm_id = event->id;
1263 	rqpair->listen_id = event->listen_id;
1264 	rqpair->qpair.transport = transport;
1265 	rqpair->qpair.trid = port->trid;
1266 	STAILQ_INIT(&rqpair->ibv_events);
1267 	/* use qid from the private data to determine the qpair type
1268 	   qid will be set to the appropriate value when the controller is created */
1269 	rqpair->qpair.qid = private_data->qid;
1270 
1271 	event->id->context = &rqpair->qpair;
1272 
1273 	spdk_nvmf_tgt_new_qpair(transport->tgt, &rqpair->qpair);
1274 
1275 	return 0;
1276 }
1277 
1278 static int
1279 nvmf_rdma_mem_notify(void *cb_ctx, struct spdk_mem_map *map,
1280 		     enum spdk_mem_map_notify_action action,
1281 		     void *vaddr, size_t size)
1282 {
1283 	struct ibv_pd *pd = cb_ctx;
1284 	struct ibv_mr *mr;
1285 	int rc;
1286 
1287 	switch (action) {
1288 	case SPDK_MEM_MAP_NOTIFY_REGISTER:
1289 		if (!g_nvmf_hooks.get_rkey) {
1290 			mr = ibv_reg_mr(pd, vaddr, size,
1291 					IBV_ACCESS_LOCAL_WRITE |
1292 					IBV_ACCESS_REMOTE_READ |
1293 					IBV_ACCESS_REMOTE_WRITE);
1294 			if (mr == NULL) {
1295 				SPDK_ERRLOG("ibv_reg_mr() failed\n");
1296 				return -1;
1297 			} else {
1298 				rc = spdk_mem_map_set_translation(map, (uint64_t)vaddr, size, (uint64_t)mr);
1299 			}
1300 		} else {
1301 			rc = spdk_mem_map_set_translation(map, (uint64_t)vaddr, size,
1302 							  g_nvmf_hooks.get_rkey(pd, vaddr, size));
1303 		}
1304 		break;
1305 	case SPDK_MEM_MAP_NOTIFY_UNREGISTER:
1306 		if (!g_nvmf_hooks.get_rkey) {
1307 			mr = (struct ibv_mr *)spdk_mem_map_translate(map, (uint64_t)vaddr, NULL);
1308 			if (mr) {
1309 				ibv_dereg_mr(mr);
1310 			}
1311 		}
1312 		rc = spdk_mem_map_clear_translation(map, (uint64_t)vaddr, size);
1313 		break;
1314 	default:
1315 		SPDK_UNREACHABLE();
1316 	}
1317 
1318 	return rc;
1319 }
1320 
1321 static int
1322 nvmf_rdma_check_contiguous_entries(uint64_t addr_1, uint64_t addr_2)
1323 {
1324 	/* Two contiguous mappings will point to the same address which is the start of the RDMA MR. */
1325 	return addr_1 == addr_2;
1326 }
1327 
1328 static inline void
1329 nvmf_rdma_setup_wr(struct ibv_send_wr *wr, struct ibv_send_wr *next,
1330 		   enum spdk_nvme_data_transfer xfer)
1331 {
1332 	if (xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1333 		wr->opcode = IBV_WR_RDMA_WRITE;
1334 		wr->send_flags = 0;
1335 		wr->next = next;
1336 	} else if (xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1337 		wr->opcode = IBV_WR_RDMA_READ;
1338 		wr->send_flags = IBV_SEND_SIGNALED;
1339 		wr->next = NULL;
1340 	} else {
1341 		assert(0);
1342 	}
1343 }
1344 
1345 static int
1346 nvmf_request_alloc_wrs(struct spdk_nvmf_rdma_transport *rtransport,
1347 		       struct spdk_nvmf_rdma_request *rdma_req,
1348 		       uint32_t num_sgl_descriptors)
1349 {
1350 	struct spdk_nvmf_rdma_request_data	*work_requests[SPDK_NVMF_MAX_SGL_ENTRIES];
1351 	struct spdk_nvmf_rdma_request_data	*current_data_wr;
1352 	uint32_t				i;
1353 
1354 	if (num_sgl_descriptors > SPDK_NVMF_MAX_SGL_ENTRIES) {
1355 		SPDK_ERRLOG("Requested too much entries (%u), the limit is %u\n",
1356 			    num_sgl_descriptors, SPDK_NVMF_MAX_SGL_ENTRIES);
1357 		return -EINVAL;
1358 	}
1359 
1360 	if (spdk_mempool_get_bulk(rtransport->data_wr_pool, (void **)work_requests, num_sgl_descriptors)) {
1361 		return -ENOMEM;
1362 	}
1363 
1364 	current_data_wr = &rdma_req->data;
1365 
1366 	for (i = 0; i < num_sgl_descriptors; i++) {
1367 		nvmf_rdma_setup_wr(&current_data_wr->wr, &work_requests[i]->wr, rdma_req->req.xfer);
1368 		current_data_wr->wr.next = &work_requests[i]->wr;
1369 		current_data_wr = work_requests[i];
1370 		current_data_wr->wr.sg_list = current_data_wr->sgl;
1371 		current_data_wr->wr.wr_id = rdma_req->data.wr.wr_id;
1372 	}
1373 
1374 	nvmf_rdma_setup_wr(&current_data_wr->wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1375 
1376 	return 0;
1377 }
1378 
1379 static inline void
1380 nvmf_rdma_setup_request(struct spdk_nvmf_rdma_request *rdma_req)
1381 {
1382 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1383 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1384 
1385 	wr->wr.rdma.rkey = sgl->keyed.key;
1386 	wr->wr.rdma.remote_addr = sgl->address;
1387 	nvmf_rdma_setup_wr(wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1388 }
1389 
1390 static inline void
1391 nvmf_rdma_update_remote_addr(struct spdk_nvmf_rdma_request *rdma_req, uint32_t num_wrs)
1392 {
1393 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1394 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1395 	uint32_t			i;
1396 	int				j;
1397 	uint64_t			remote_addr_offset = 0;
1398 
1399 	for (i = 0; i < num_wrs; ++i) {
1400 		wr->wr.rdma.rkey = sgl->keyed.key;
1401 		wr->wr.rdma.remote_addr = sgl->address + remote_addr_offset;
1402 		for (j = 0; j < wr->num_sge; ++j) {
1403 			remote_addr_offset += wr->sg_list[j].length;
1404 		}
1405 		wr = wr->next;
1406 	}
1407 }
1408 
1409 /* This function is used in the rare case that we have a buffer split over multiple memory regions. */
1410 static int
1411 nvmf_rdma_replace_buffer(struct spdk_nvmf_rdma_poll_group *rgroup, void **buf)
1412 {
1413 	struct spdk_nvmf_transport_poll_group	*group = &rgroup->group;
1414 	struct spdk_nvmf_transport		*transport = group->transport;
1415 	struct spdk_nvmf_transport_pg_cache_buf	*old_buf;
1416 	void					*new_buf;
1417 
1418 	if (!(STAILQ_EMPTY(&group->buf_cache))) {
1419 		group->buf_cache_count--;
1420 		new_buf = STAILQ_FIRST(&group->buf_cache);
1421 		STAILQ_REMOVE_HEAD(&group->buf_cache, link);
1422 		assert(*buf != NULL);
1423 	} else {
1424 		new_buf = spdk_mempool_get(transport->data_buf_pool);
1425 	}
1426 
1427 	if (*buf == NULL) {
1428 		return -ENOMEM;
1429 	}
1430 
1431 	old_buf = *buf;
1432 	STAILQ_INSERT_HEAD(&rgroup->retired_bufs, old_buf, link);
1433 	*buf = new_buf;
1434 	return 0;
1435 }
1436 
1437 static bool
1438 nvmf_rdma_get_lkey(struct spdk_nvmf_rdma_device *device, struct iovec *iov,
1439 		   uint32_t *_lkey)
1440 {
1441 	uint64_t	translation_len;
1442 	uint32_t	lkey;
1443 
1444 	translation_len = iov->iov_len;
1445 
1446 	if (!g_nvmf_hooks.get_rkey) {
1447 		lkey = ((struct ibv_mr *)spdk_mem_map_translate(device->map,
1448 				(uint64_t)iov->iov_base, &translation_len))->lkey;
1449 	} else {
1450 		lkey = spdk_mem_map_translate(device->map,
1451 					      (uint64_t)iov->iov_base, &translation_len);
1452 	}
1453 
1454 	if (spdk_unlikely(translation_len < iov->iov_len)) {
1455 		return false;
1456 	}
1457 
1458 	*_lkey = lkey;
1459 	return true;
1460 }
1461 
1462 static bool
1463 nvmf_rdma_fill_wr_sge(struct spdk_nvmf_rdma_device *device,
1464 		      struct iovec *iov, struct ibv_send_wr **_wr,
1465 		      uint32_t *_remaining_data_block, uint32_t *_offset,
1466 		      uint32_t *_num_extra_wrs,
1467 		      const struct spdk_dif_ctx *dif_ctx)
1468 {
1469 	struct ibv_send_wr *wr = *_wr;
1470 	struct ibv_sge	*sg_ele = &wr->sg_list[wr->num_sge];
1471 	uint32_t	lkey = 0;
1472 	uint32_t	remaining, data_block_size, md_size, sge_len;
1473 
1474 	if (spdk_unlikely(!nvmf_rdma_get_lkey(device, iov, &lkey))) {
1475 		/* This is a very rare case that can occur when using DPDK version < 19.05 */
1476 		SPDK_ERRLOG("Data buffer split over multiple RDMA Memory Regions. Removing it from circulation.\n");
1477 		return false;
1478 	}
1479 
1480 	if (spdk_likely(!dif_ctx)) {
1481 		sg_ele->lkey = lkey;
1482 		sg_ele->addr = (uintptr_t)(iov->iov_base);
1483 		sg_ele->length = iov->iov_len;
1484 		wr->num_sge++;
1485 	} else {
1486 		remaining = iov->iov_len - *_offset;
1487 		data_block_size = dif_ctx->block_size - dif_ctx->md_size;
1488 		md_size = dif_ctx->md_size;
1489 
1490 		while (remaining) {
1491 			if (wr->num_sge >= SPDK_NVMF_MAX_SGL_ENTRIES) {
1492 				if (*_num_extra_wrs > 0 && wr->next) {
1493 					*_wr = wr->next;
1494 					wr = *_wr;
1495 					wr->num_sge = 0;
1496 					sg_ele = &wr->sg_list[wr->num_sge];
1497 					(*_num_extra_wrs)--;
1498 				} else {
1499 					break;
1500 				}
1501 			}
1502 			sg_ele->lkey = lkey;
1503 			sg_ele->addr = (uintptr_t)((char *)iov->iov_base + *_offset);
1504 			sge_len = spdk_min(remaining, *_remaining_data_block);
1505 			sg_ele->length = sge_len;
1506 			remaining -= sge_len;
1507 			*_remaining_data_block -= sge_len;
1508 			*_offset += sge_len;
1509 
1510 			sg_ele++;
1511 			wr->num_sge++;
1512 
1513 			if (*_remaining_data_block == 0) {
1514 				/* skip metadata */
1515 				*_offset += md_size;
1516 				/* Metadata that do not fit this IO buffer will be included in the next IO buffer */
1517 				remaining -= spdk_min(remaining, md_size);
1518 				*_remaining_data_block = data_block_size;
1519 			}
1520 
1521 			if (remaining == 0) {
1522 				/* By subtracting the size of the last IOV from the offset, we ensure that we skip
1523 				   the remaining metadata bits at the beginning of the next buffer */
1524 				*_offset -= iov->iov_len;
1525 			}
1526 		}
1527 	}
1528 
1529 	return true;
1530 }
1531 
1532 static int
1533 nvmf_rdma_fill_wr_sgl(struct spdk_nvmf_rdma_poll_group *rgroup,
1534 		      struct spdk_nvmf_rdma_device *device,
1535 		      struct spdk_nvmf_rdma_request *rdma_req,
1536 		      struct ibv_send_wr *wr,
1537 		      uint32_t length,
1538 		      uint32_t num_extra_wrs)
1539 {
1540 	struct spdk_nvmf_request *req = &rdma_req->req;
1541 	struct spdk_dif_ctx *dif_ctx = NULL;
1542 	uint32_t remaining_data_block = 0;
1543 	uint32_t offset = 0;
1544 
1545 	if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
1546 		dif_ctx = &rdma_req->req.dif.dif_ctx;
1547 		remaining_data_block = dif_ctx->block_size - dif_ctx->md_size;
1548 	}
1549 
1550 	wr->num_sge = 0;
1551 
1552 	while (length && (num_extra_wrs || wr->num_sge < SPDK_NVMF_MAX_SGL_ENTRIES)) {
1553 		while (spdk_unlikely(!nvmf_rdma_fill_wr_sge(device, &req->iov[rdma_req->iovpos], &wr,
1554 				     &remaining_data_block, &offset, &num_extra_wrs, dif_ctx))) {
1555 			if (nvmf_rdma_replace_buffer(rgroup, &req->buffers[rdma_req->iovpos]) == -ENOMEM) {
1556 				return -ENOMEM;
1557 			}
1558 			req->iov[rdma_req->iovpos].iov_base = (void *)((uintptr_t)(req->buffers[rdma_req->iovpos] +
1559 							      NVMF_DATA_BUFFER_MASK) &
1560 							      ~NVMF_DATA_BUFFER_MASK);
1561 		}
1562 
1563 		length -= req->iov[rdma_req->iovpos].iov_len;
1564 		rdma_req->iovpos++;
1565 	}
1566 
1567 	if (length) {
1568 		SPDK_ERRLOG("Not enough SG entries to hold data buffer\n");
1569 		return -EINVAL;
1570 	}
1571 
1572 	return 0;
1573 }
1574 
1575 static inline uint32_t
1576 nvmf_rdma_calc_num_wrs(uint32_t length, uint32_t io_unit_size, uint32_t block_size)
1577 {
1578 	/* estimate the number of SG entries and WRs needed to process the request */
1579 	uint32_t num_sge = 0;
1580 	uint32_t i;
1581 	uint32_t num_buffers = SPDK_CEIL_DIV(length, io_unit_size);
1582 
1583 	for (i = 0; i < num_buffers && length > 0; i++) {
1584 		uint32_t buffer_len = spdk_min(length, io_unit_size);
1585 		uint32_t num_sge_in_block = SPDK_CEIL_DIV(buffer_len, block_size);
1586 
1587 		if (num_sge_in_block * block_size > buffer_len) {
1588 			++num_sge_in_block;
1589 		}
1590 		num_sge += num_sge_in_block;
1591 		length -= buffer_len;
1592 	}
1593 	return SPDK_CEIL_DIV(num_sge, SPDK_NVMF_MAX_SGL_ENTRIES);
1594 }
1595 
1596 static int
1597 nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1598 			    struct spdk_nvmf_rdma_device *device,
1599 			    struct spdk_nvmf_rdma_request *rdma_req,
1600 			    uint32_t length)
1601 {
1602 	struct spdk_nvmf_rdma_qpair		*rqpair;
1603 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1604 	struct spdk_nvmf_request		*req = &rdma_req->req;
1605 	struct ibv_send_wr			*wr = &rdma_req->data.wr;
1606 	int					rc;
1607 	uint32_t				num_wrs = 1;
1608 
1609 	rqpair = SPDK_CONTAINEROF(req->qpair, struct spdk_nvmf_rdma_qpair, qpair);
1610 	rgroup = rqpair->poller->group;
1611 
1612 	/* rdma wr specifics */
1613 	nvmf_rdma_setup_request(rdma_req);
1614 
1615 	rc = spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport,
1616 					   length);
1617 	if (rc != 0) {
1618 		return rc;
1619 	}
1620 
1621 	assert(req->iovcnt <= rqpair->max_send_sge);
1622 
1623 	rdma_req->iovpos = 0;
1624 
1625 	if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1626 		num_wrs = nvmf_rdma_calc_num_wrs(length, rtransport->transport.opts.io_unit_size,
1627 						 req->dif.dif_ctx.block_size);
1628 		if (num_wrs > 1) {
1629 			rc = nvmf_request_alloc_wrs(rtransport, rdma_req, num_wrs - 1);
1630 			if (rc != 0) {
1631 				goto err_exit;
1632 			}
1633 		}
1634 	}
1635 
1636 	rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, wr, length, num_wrs - 1);
1637 	if (spdk_unlikely(rc != 0)) {
1638 		goto err_exit;
1639 	}
1640 
1641 	if (spdk_unlikely(num_wrs > 1)) {
1642 		nvmf_rdma_update_remote_addr(rdma_req, num_wrs);
1643 	}
1644 
1645 	/* set the number of outstanding data WRs for this request. */
1646 	rdma_req->num_outstanding_data_wr = num_wrs;
1647 
1648 	return rc;
1649 
1650 err_exit:
1651 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1652 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1653 	req->iovcnt = 0;
1654 	return rc;
1655 }
1656 
1657 static int
1658 nvmf_rdma_request_fill_iovs_multi_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1659 				      struct spdk_nvmf_rdma_device *device,
1660 				      struct spdk_nvmf_rdma_request *rdma_req)
1661 {
1662 	struct spdk_nvmf_rdma_qpair		*rqpair;
1663 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1664 	struct ibv_send_wr			*current_wr;
1665 	struct spdk_nvmf_request		*req = &rdma_req->req;
1666 	struct spdk_nvme_sgl_descriptor		*inline_segment, *desc;
1667 	uint32_t				num_sgl_descriptors;
1668 	uint32_t				lengths[SPDK_NVMF_MAX_SGL_ENTRIES];
1669 	uint32_t				i;
1670 	int					rc;
1671 
1672 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1673 	rgroup = rqpair->poller->group;
1674 
1675 	inline_segment = &req->cmd->nvme_cmd.dptr.sgl1;
1676 	assert(inline_segment->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT);
1677 	assert(inline_segment->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET);
1678 
1679 	num_sgl_descriptors = inline_segment->unkeyed.length / sizeof(struct spdk_nvme_sgl_descriptor);
1680 	assert(num_sgl_descriptors <= SPDK_NVMF_MAX_SGL_ENTRIES);
1681 
1682 	if (nvmf_request_alloc_wrs(rtransport, rdma_req, num_sgl_descriptors - 1) != 0) {
1683 		return -ENOMEM;
1684 	}
1685 
1686 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1687 	for (i = 0; i < num_sgl_descriptors; i++) {
1688 		if (spdk_likely(!req->dif.dif_insert_or_strip)) {
1689 			lengths[i] = desc->keyed.length;
1690 		} else {
1691 			req->dif.orig_length += desc->keyed.length;
1692 			lengths[i] = spdk_dif_get_length_with_md(desc->keyed.length, &req->dif.dif_ctx);
1693 			req->dif.elba_length += lengths[i];
1694 		}
1695 		desc++;
1696 	}
1697 
1698 	rc = spdk_nvmf_request_get_buffers_multi(req, &rgroup->group, &rtransport->transport,
1699 			lengths, num_sgl_descriptors);
1700 	if (rc != 0) {
1701 		nvmf_rdma_request_free_data(rdma_req, rtransport);
1702 		return rc;
1703 	}
1704 
1705 	/* The first WR must always be the embedded data WR. This is how we unwind them later. */
1706 	current_wr = &rdma_req->data.wr;
1707 	assert(current_wr != NULL);
1708 
1709 	req->length = 0;
1710 	rdma_req->iovpos = 0;
1711 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1712 	for (i = 0; i < num_sgl_descriptors; i++) {
1713 		/* The descriptors must be keyed data block descriptors with an address, not an offset. */
1714 		if (spdk_unlikely(desc->generic.type != SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK ||
1715 				  desc->keyed.subtype != SPDK_NVME_SGL_SUBTYPE_ADDRESS)) {
1716 			rc = -EINVAL;
1717 			goto err_exit;
1718 		}
1719 
1720 		current_wr->num_sge = 0;
1721 
1722 		rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, current_wr, lengths[i], 0);
1723 		if (rc != 0) {
1724 			rc = -ENOMEM;
1725 			goto err_exit;
1726 		}
1727 
1728 		req->length += desc->keyed.length;
1729 		current_wr->wr.rdma.rkey = desc->keyed.key;
1730 		current_wr->wr.rdma.remote_addr = desc->address;
1731 		current_wr = current_wr->next;
1732 		desc++;
1733 	}
1734 
1735 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1736 	/* Go back to the last descriptor in the list. */
1737 	desc--;
1738 	if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1739 		if (desc->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1740 			rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1741 			rdma_req->rsp.wr.imm_data = desc->keyed.key;
1742 		}
1743 	}
1744 #endif
1745 
1746 	rdma_req->num_outstanding_data_wr = num_sgl_descriptors;
1747 
1748 	return 0;
1749 
1750 err_exit:
1751 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1752 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1753 	return rc;
1754 }
1755 
1756 static int
1757 nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1758 			    struct spdk_nvmf_rdma_device *device,
1759 			    struct spdk_nvmf_rdma_request *rdma_req)
1760 {
1761 	struct spdk_nvmf_request		*req = &rdma_req->req;
1762 	struct spdk_nvme_cpl			*rsp;
1763 	struct spdk_nvme_sgl_descriptor		*sgl;
1764 	int					rc;
1765 	uint32_t				length;
1766 
1767 	rsp = &req->rsp->nvme_cpl;
1768 	sgl = &req->cmd->nvme_cmd.dptr.sgl1;
1769 
1770 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1771 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1772 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1773 
1774 		length = sgl->keyed.length;
1775 		if (length > rtransport->transport.opts.max_io_size) {
1776 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1777 				    length, rtransport->transport.opts.max_io_size);
1778 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1779 			return -1;
1780 		}
1781 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1782 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1783 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1784 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1785 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1786 			}
1787 		}
1788 #endif
1789 
1790 		/* fill request length and populate iovs */
1791 		req->length = length;
1792 
1793 		if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1794 			req->dif.orig_length = length;
1795 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
1796 			req->dif.elba_length = length;
1797 		}
1798 
1799 		rc = nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req, length);
1800 		if (spdk_unlikely(rc < 0)) {
1801 			if (rc == -EINVAL) {
1802 				SPDK_ERRLOG("SGL length exceeds the max I/O size\n");
1803 				rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1804 				return -1;
1805 			}
1806 			/* No available buffers. Queue this request up. */
1807 			SPDK_DEBUGLOG(rdma, "No available large data buffers. Queueing request %p\n", rdma_req);
1808 			return 0;
1809 		}
1810 
1811 		/* backward compatible */
1812 		req->data = req->iov[0].iov_base;
1813 
1814 		SPDK_DEBUGLOG(rdma, "Request %p took %d buffer/s from central pool\n", rdma_req,
1815 			      req->iovcnt);
1816 
1817 		return 0;
1818 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1819 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1820 		uint64_t offset = sgl->address;
1821 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1822 
1823 		SPDK_DEBUGLOG(nvmf, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1824 			      offset, sgl->unkeyed.length);
1825 
1826 		if (offset > max_len) {
1827 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1828 				    offset, max_len);
1829 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1830 			return -1;
1831 		}
1832 		max_len -= (uint32_t)offset;
1833 
1834 		if (sgl->unkeyed.length > max_len) {
1835 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1836 				    sgl->unkeyed.length, max_len);
1837 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1838 			return -1;
1839 		}
1840 
1841 		rdma_req->num_outstanding_data_wr = 0;
1842 		req->data = rdma_req->recv->buf + offset;
1843 		req->data_from_pool = false;
1844 		req->length = sgl->unkeyed.length;
1845 
1846 		req->iov[0].iov_base = req->data;
1847 		req->iov[0].iov_len = req->length;
1848 		req->iovcnt = 1;
1849 
1850 		return 0;
1851 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT &&
1852 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1853 
1854 		rc = nvmf_rdma_request_fill_iovs_multi_sgl(rtransport, device, rdma_req);
1855 		if (rc == -ENOMEM) {
1856 			SPDK_DEBUGLOG(rdma, "No available large data buffers. Queueing request %p\n", rdma_req);
1857 			return 0;
1858 		} else if (rc == -EINVAL) {
1859 			SPDK_ERRLOG("Multi SGL element request length exceeds the max I/O size\n");
1860 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1861 			return -1;
1862 		}
1863 
1864 		/* backward compatible */
1865 		req->data = req->iov[0].iov_base;
1866 
1867 		SPDK_DEBUGLOG(rdma, "Request %p took %d buffer/s from central pool\n", rdma_req,
1868 			      req->iovcnt);
1869 
1870 		return 0;
1871 	}
1872 
1873 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1874 		    sgl->generic.type, sgl->generic.subtype);
1875 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1876 	return -1;
1877 }
1878 
1879 static void
1880 _nvmf_rdma_request_free(struct spdk_nvmf_rdma_request *rdma_req,
1881 			struct spdk_nvmf_rdma_transport	*rtransport)
1882 {
1883 	struct spdk_nvmf_rdma_qpair		*rqpair;
1884 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1885 
1886 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1887 	if (rdma_req->req.data_from_pool) {
1888 		rgroup = rqpair->poller->group;
1889 
1890 		spdk_nvmf_request_free_buffers(&rdma_req->req, &rgroup->group, &rtransport->transport);
1891 	}
1892 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1893 	rdma_req->req.length = 0;
1894 	rdma_req->req.iovcnt = 0;
1895 	rdma_req->req.data = NULL;
1896 	rdma_req->rsp.wr.next = NULL;
1897 	rdma_req->data.wr.next = NULL;
1898 	memset(&rdma_req->req.dif, 0, sizeof(rdma_req->req.dif));
1899 	rqpair->qd--;
1900 
1901 	STAILQ_INSERT_HEAD(&rqpair->resources->free_queue, rdma_req, state_link);
1902 	rdma_req->state = RDMA_REQUEST_STATE_FREE;
1903 }
1904 
1905 bool
1906 nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
1907 			  struct spdk_nvmf_rdma_request *rdma_req)
1908 {
1909 	struct spdk_nvmf_rdma_qpair	*rqpair;
1910 	struct spdk_nvmf_rdma_device	*device;
1911 	struct spdk_nvmf_rdma_poll_group *rgroup;
1912 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
1913 	int				rc;
1914 	struct spdk_nvmf_rdma_recv	*rdma_recv;
1915 	enum spdk_nvmf_rdma_request_state prev_state;
1916 	bool				progress = false;
1917 	int				data_posted;
1918 	uint32_t			num_blocks;
1919 
1920 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1921 	device = rqpair->device;
1922 	rgroup = rqpair->poller->group;
1923 
1924 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
1925 
1926 	/* If the queue pair is in an error state, force the request to the completed state
1927 	 * to release resources. */
1928 	if (rqpair->ibv_state == IBV_QPS_ERR || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1929 		if (rdma_req->state == RDMA_REQUEST_STATE_NEED_BUFFER) {
1930 			STAILQ_REMOVE(&rgroup->group.pending_buf_queue, &rdma_req->req, spdk_nvmf_request, buf_link);
1931 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING) {
1932 			STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1933 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING) {
1934 			STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1935 		}
1936 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1937 	}
1938 
1939 	/* The loop here is to allow for several back-to-back state changes. */
1940 	do {
1941 		prev_state = rdma_req->state;
1942 
1943 		SPDK_DEBUGLOG(rdma, "Request %p entering state %d\n", rdma_req, prev_state);
1944 
1945 		switch (rdma_req->state) {
1946 		case RDMA_REQUEST_STATE_FREE:
1947 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
1948 			 * to escape this state. */
1949 			break;
1950 		case RDMA_REQUEST_STATE_NEW:
1951 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
1952 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1953 			rdma_recv = rdma_req->recv;
1954 
1955 			/* The first element of the SGL is the NVMe command */
1956 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
1957 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
1958 
1959 			if (rqpair->ibv_state == IBV_QPS_ERR  || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1960 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1961 				break;
1962 			}
1963 
1964 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&rdma_req->req, &rdma_req->req.dif.dif_ctx))) {
1965 				rdma_req->req.dif.dif_insert_or_strip = true;
1966 			}
1967 
1968 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1969 			rdma_req->rsp.wr.opcode = IBV_WR_SEND;
1970 			rdma_req->rsp.wr.imm_data = 0;
1971 #endif
1972 
1973 			/* The next state transition depends on the data transfer needs of this request. */
1974 			rdma_req->req.xfer = spdk_nvmf_req_get_xfer(&rdma_req->req);
1975 
1976 			if (spdk_unlikely(rdma_req->req.xfer == SPDK_NVME_DATA_BIDIRECTIONAL)) {
1977 				rsp->status.sct = SPDK_NVME_SCT_GENERIC;
1978 				rsp->status.sc = SPDK_NVME_SC_INVALID_OPCODE;
1979 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1980 				SPDK_DEBUGLOG(rdma, "Request %p: invalid xfer type (BIDIRECTIONAL)\n", rdma_req);
1981 				break;
1982 			}
1983 
1984 			/* If no data to transfer, ready to execute. */
1985 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
1986 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1987 				break;
1988 			}
1989 
1990 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
1991 			STAILQ_INSERT_TAIL(&rgroup->group.pending_buf_queue, &rdma_req->req, buf_link);
1992 			break;
1993 		case RDMA_REQUEST_STATE_NEED_BUFFER:
1994 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
1995 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1996 
1997 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
1998 
1999 			if (&rdma_req->req != STAILQ_FIRST(&rgroup->group.pending_buf_queue)) {
2000 				/* This request needs to wait in line to obtain a buffer */
2001 				break;
2002 			}
2003 
2004 			/* Try to get a data buffer */
2005 			rc = nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
2006 			if (rc < 0) {
2007 				STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2008 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2009 				break;
2010 			}
2011 
2012 			if (!rdma_req->req.data) {
2013 				/* No buffers available. */
2014 				rgroup->stat.pending_data_buffer++;
2015 				break;
2016 			}
2017 
2018 			STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2019 
2020 			/* If data is transferring from host to controller and the data didn't
2021 			 * arrive using in capsule data, we need to do a transfer from the host.
2022 			 */
2023 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER &&
2024 			    rdma_req->req.data_from_pool) {
2025 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
2026 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
2027 				break;
2028 			}
2029 
2030 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
2031 			break;
2032 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
2033 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING, 0, 0,
2034 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2035 
2036 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_read_queue)) {
2037 				/* This request needs to wait in line to perform RDMA */
2038 				break;
2039 			}
2040 			if (rqpair->current_send_depth + rdma_req->num_outstanding_data_wr > rqpair->max_send_depth
2041 			    || rqpair->current_read_depth + rdma_req->num_outstanding_data_wr > rqpair->max_read_depth) {
2042 				/* We can only have so many WRs outstanding. we have to wait until some finish. */
2043 				rqpair->poller->stat.pending_rdma_read++;
2044 				break;
2045 			}
2046 
2047 			/* We have already verified that this request is the head of the queue. */
2048 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_read_queue, state_link);
2049 
2050 			rc = request_transfer_in(&rdma_req->req);
2051 			if (!rc) {
2052 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
2053 			} else {
2054 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
2055 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2056 			}
2057 			break;
2058 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2059 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2060 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2061 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
2062 			 * to escape this state. */
2063 			break;
2064 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
2065 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
2066 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2067 
2068 			if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
2069 				if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2070 					/* generate DIF for write operation */
2071 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2072 					assert(num_blocks > 0);
2073 
2074 					rc = spdk_dif_generate(rdma_req->req.iov, rdma_req->req.iovcnt,
2075 							       num_blocks, &rdma_req->req.dif.dif_ctx);
2076 					if (rc != 0) {
2077 						SPDK_ERRLOG("DIF generation failed\n");
2078 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2079 						spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2080 						break;
2081 					}
2082 				}
2083 
2084 				assert(rdma_req->req.dif.elba_length >= rdma_req->req.length);
2085 				/* set extended length before IO operation */
2086 				rdma_req->req.length = rdma_req->req.dif.elba_length;
2087 			}
2088 
2089 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
2090 			spdk_nvmf_request_exec(&rdma_req->req);
2091 			break;
2092 		case RDMA_REQUEST_STATE_EXECUTING:
2093 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
2094 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2095 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
2096 			 * to escape this state. */
2097 			break;
2098 		case RDMA_REQUEST_STATE_EXECUTED:
2099 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
2100 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2101 			if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
2102 			    rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2103 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_write_queue, rdma_req, state_link);
2104 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING;
2105 			} else {
2106 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2107 			}
2108 			if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
2109 				/* restore the original length */
2110 				rdma_req->req.length = rdma_req->req.dif.orig_length;
2111 
2112 				if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2113 					struct spdk_dif_error error_blk;
2114 
2115 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2116 
2117 					rc = spdk_dif_verify(rdma_req->req.iov, rdma_req->req.iovcnt, num_blocks,
2118 							     &rdma_req->req.dif.dif_ctx, &error_blk);
2119 					if (rc) {
2120 						struct spdk_nvme_cpl *rsp = &rdma_req->req.rsp->nvme_cpl;
2121 
2122 						SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n", error_blk.err_type,
2123 							    error_blk.err_offset);
2124 						rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2125 						rsp->status.sc = nvmf_rdma_dif_error_to_compl_status(error_blk.err_type);
2126 						rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2127 						STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2128 					}
2129 				}
2130 			}
2131 			break;
2132 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
2133 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING, 0, 0,
2134 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2135 
2136 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_write_queue)) {
2137 				/* This request needs to wait in line to perform RDMA */
2138 				break;
2139 			}
2140 			if ((rqpair->current_send_depth + rdma_req->num_outstanding_data_wr + 1) >
2141 			    rqpair->max_send_depth) {
2142 				/* We can only have so many WRs outstanding. we have to wait until some finish.
2143 				 * +1 since each request has an additional wr in the resp. */
2144 				rqpair->poller->stat.pending_rdma_write++;
2145 				break;
2146 			}
2147 
2148 			/* We have already verified that this request is the head of the queue. */
2149 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_write_queue, state_link);
2150 
2151 			/* The data transfer will be kicked off from
2152 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
2153 			 */
2154 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2155 			break;
2156 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
2157 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
2158 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2159 			rc = request_transfer_out(&rdma_req->req, &data_posted);
2160 			assert(rc == 0); /* No good way to handle this currently */
2161 			if (rc) {
2162 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2163 			} else {
2164 				rdma_req->state = data_posted ? RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
2165 						  RDMA_REQUEST_STATE_COMPLETING;
2166 			}
2167 			break;
2168 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2169 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2170 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2171 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2172 			 * to escape this state. */
2173 			break;
2174 		case RDMA_REQUEST_STATE_COMPLETING:
2175 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
2176 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2177 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2178 			 * to escape this state. */
2179 			break;
2180 		case RDMA_REQUEST_STATE_COMPLETED:
2181 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
2182 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2183 
2184 			rqpair->poller->stat.request_latency += spdk_get_ticks() - rdma_req->receive_tsc;
2185 			_nvmf_rdma_request_free(rdma_req, rtransport);
2186 			break;
2187 		case RDMA_REQUEST_NUM_STATES:
2188 		default:
2189 			assert(0);
2190 			break;
2191 		}
2192 
2193 		if (rdma_req->state != prev_state) {
2194 			progress = true;
2195 		}
2196 	} while (rdma_req->state != prev_state);
2197 
2198 	return progress;
2199 }
2200 
2201 /* Public API callbacks begin here */
2202 
2203 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
2204 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
2205 #define SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH 4096
2206 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
2207 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2208 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
2209 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
2210 #define SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS 4095
2211 #define SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE 32
2212 #define SPDK_NVMF_RDMA_DEFAULT_NO_SRQ false
2213 #define SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP false
2214 #define SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG 100
2215 #define SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC 1
2216 
2217 static void
2218 nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
2219 {
2220 	opts->max_queue_depth =		SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
2221 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2222 	opts->in_capsule_data_size =	SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
2223 	opts->max_io_size =		SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
2224 	opts->io_unit_size =		SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE;
2225 	opts->max_aq_depth =		SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
2226 	opts->num_shared_buffers =	SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS;
2227 	opts->buf_cache_size =		SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE;
2228 	opts->max_srq_depth =		SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH;
2229 	opts->no_srq =			SPDK_NVMF_RDMA_DEFAULT_NO_SRQ;
2230 	opts->dif_insert_or_strip =	SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP;
2231 	opts->acceptor_backlog =	SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2232 	opts->abort_timeout_sec =	SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC;
2233 }
2234 
2235 const struct spdk_mem_map_ops g_nvmf_rdma_map_ops = {
2236 	.notify_cb = nvmf_rdma_mem_notify,
2237 	.are_contiguous = nvmf_rdma_check_contiguous_entries
2238 };
2239 
2240 static int nvmf_rdma_destroy(struct spdk_nvmf_transport *transport);
2241 
2242 static struct spdk_nvmf_transport *
2243 nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
2244 {
2245 	int rc;
2246 	struct spdk_nvmf_rdma_transport *rtransport;
2247 	struct spdk_nvmf_rdma_device	*device, *tmp;
2248 	struct ibv_context		**contexts;
2249 	uint32_t			i;
2250 	int				flag;
2251 	uint32_t			sge_count;
2252 	uint32_t			min_shared_buffers;
2253 	int				max_device_sge = SPDK_NVMF_MAX_SGL_ENTRIES;
2254 	pthread_mutexattr_t		attr;
2255 
2256 	rtransport = calloc(1, sizeof(*rtransport));
2257 	if (!rtransport) {
2258 		return NULL;
2259 	}
2260 
2261 	if (pthread_mutexattr_init(&attr)) {
2262 		SPDK_ERRLOG("pthread_mutexattr_init() failed\n");
2263 		free(rtransport);
2264 		return NULL;
2265 	}
2266 
2267 	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) {
2268 		SPDK_ERRLOG("pthread_mutexattr_settype() failed\n");
2269 		pthread_mutexattr_destroy(&attr);
2270 		free(rtransport);
2271 		return NULL;
2272 	}
2273 
2274 	if (pthread_mutex_init(&rtransport->lock, &attr)) {
2275 		SPDK_ERRLOG("pthread_mutex_init() failed\n");
2276 		pthread_mutexattr_destroy(&attr);
2277 		free(rtransport);
2278 		return NULL;
2279 	}
2280 
2281 	pthread_mutexattr_destroy(&attr);
2282 
2283 	TAILQ_INIT(&rtransport->devices);
2284 	TAILQ_INIT(&rtransport->ports);
2285 	TAILQ_INIT(&rtransport->poll_groups);
2286 
2287 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
2288 
2289 	SPDK_INFOLOG(rdma, "*** RDMA Transport Init ***\n"
2290 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
2291 		     "  max_io_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
2292 		     "  in_capsule_data_size=%d, max_aq_depth=%d,\n"
2293 		     "  num_shared_buffers=%d, max_srq_depth=%d, no_srq=%d,"
2294 		     "  acceptor_backlog=%d, abort_timeout_sec=%d\n",
2295 		     opts->max_queue_depth,
2296 		     opts->max_io_size,
2297 		     opts->max_qpairs_per_ctrlr - 1,
2298 		     opts->io_unit_size,
2299 		     opts->in_capsule_data_size,
2300 		     opts->max_aq_depth,
2301 		     opts->num_shared_buffers,
2302 		     opts->max_srq_depth,
2303 		     opts->no_srq,
2304 		     opts->acceptor_backlog,
2305 		     opts->abort_timeout_sec);
2306 
2307 	/* I/O unit size cannot be larger than max I/O size */
2308 	if (opts->io_unit_size > opts->max_io_size) {
2309 		opts->io_unit_size = opts->max_io_size;
2310 	}
2311 
2312 	if (opts->acceptor_backlog <= 0) {
2313 		SPDK_ERRLOG("The acceptor backlog cannot be less than 1, setting to the default value of (%d).\n",
2314 			    SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG);
2315 		opts->acceptor_backlog = SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2316 	}
2317 
2318 	if (opts->num_shared_buffers < (SPDK_NVMF_MAX_SGL_ENTRIES * 2)) {
2319 		SPDK_ERRLOG("The number of shared data buffers (%d) is less than"
2320 			    "the minimum number required to guarantee that forward progress can be made (%d)\n",
2321 			    opts->num_shared_buffers, (SPDK_NVMF_MAX_SGL_ENTRIES * 2));
2322 		nvmf_rdma_destroy(&rtransport->transport);
2323 		return NULL;
2324 	}
2325 
2326 	min_shared_buffers = spdk_env_get_core_count() * opts->buf_cache_size;
2327 	if (min_shared_buffers > opts->num_shared_buffers) {
2328 		SPDK_ERRLOG("There are not enough buffers to satisfy"
2329 			    "per-poll group caches for each thread. (%" PRIu32 ")"
2330 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
2331 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
2332 		nvmf_rdma_destroy(&rtransport->transport);
2333 		return NULL;
2334 	}
2335 
2336 	sge_count = opts->max_io_size / opts->io_unit_size;
2337 	if (sge_count > NVMF_DEFAULT_TX_SGE) {
2338 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
2339 		nvmf_rdma_destroy(&rtransport->transport);
2340 		return NULL;
2341 	}
2342 
2343 	rtransport->event_channel = rdma_create_event_channel();
2344 	if (rtransport->event_channel == NULL) {
2345 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
2346 		nvmf_rdma_destroy(&rtransport->transport);
2347 		return NULL;
2348 	}
2349 
2350 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
2351 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2352 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
2353 			    rtransport->event_channel->fd, spdk_strerror(errno));
2354 		nvmf_rdma_destroy(&rtransport->transport);
2355 		return NULL;
2356 	}
2357 
2358 	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data",
2359 				   opts->max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES,
2360 				   sizeof(struct spdk_nvmf_rdma_request_data),
2361 				   SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
2362 				   SPDK_ENV_SOCKET_ID_ANY);
2363 	if (!rtransport->data_wr_pool) {
2364 		SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");
2365 		nvmf_rdma_destroy(&rtransport->transport);
2366 		return NULL;
2367 	}
2368 
2369 	contexts = rdma_get_devices(NULL);
2370 	if (contexts == NULL) {
2371 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2372 		nvmf_rdma_destroy(&rtransport->transport);
2373 		return NULL;
2374 	}
2375 
2376 	i = 0;
2377 	rc = 0;
2378 	while (contexts[i] != NULL) {
2379 		device = calloc(1, sizeof(*device));
2380 		if (!device) {
2381 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
2382 			rc = -ENOMEM;
2383 			break;
2384 		}
2385 		device->context = contexts[i];
2386 		rc = ibv_query_device(device->context, &device->attr);
2387 		if (rc < 0) {
2388 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2389 			free(device);
2390 			break;
2391 
2392 		}
2393 
2394 		max_device_sge = spdk_min(max_device_sge, device->attr.max_sge);
2395 
2396 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2397 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
2398 			SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
2399 			SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
2400 		}
2401 
2402 		/**
2403 		 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
2404 		 * The Soft-RoCE RXE driver does not currently support send with invalidate,
2405 		 * but incorrectly reports that it does. There are changes making their way
2406 		 * through the kernel now that will enable this feature. When they are merged,
2407 		 * we can conditionally enable this feature.
2408 		 *
2409 		 * TODO: enable this for versions of the kernel rxe driver that support it.
2410 		 */
2411 		if (device->attr.vendor_id == 0) {
2412 			device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
2413 		}
2414 #endif
2415 
2416 		/* set up device context async ev fd as NON_BLOCKING */
2417 		flag = fcntl(device->context->async_fd, F_GETFL);
2418 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
2419 		if (rc < 0) {
2420 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
2421 			free(device);
2422 			break;
2423 		}
2424 
2425 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
2426 		i++;
2427 
2428 		if (g_nvmf_hooks.get_ibv_pd) {
2429 			device->pd = g_nvmf_hooks.get_ibv_pd(NULL, device->context);
2430 		} else {
2431 			device->pd = ibv_alloc_pd(device->context);
2432 		}
2433 
2434 		if (!device->pd) {
2435 			SPDK_ERRLOG("Unable to allocate protection domain.\n");
2436 			rc = -ENOMEM;
2437 			break;
2438 		}
2439 
2440 		assert(device->map == NULL);
2441 
2442 		device->map = spdk_mem_map_alloc(0, &g_nvmf_rdma_map_ops, device->pd);
2443 		if (!device->map) {
2444 			SPDK_ERRLOG("Unable to allocate memory map for listen address\n");
2445 			rc = -ENOMEM;
2446 			break;
2447 		}
2448 
2449 		assert(device->map != NULL);
2450 		assert(device->pd != NULL);
2451 	}
2452 	rdma_free_devices(contexts);
2453 
2454 	if (opts->io_unit_size * max_device_sge < opts->max_io_size) {
2455 		/* divide and round up. */
2456 		opts->io_unit_size = (opts->max_io_size + max_device_sge - 1) / max_device_sge;
2457 
2458 		/* round up to the nearest 4k. */
2459 		opts->io_unit_size = (opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT - 1) & ~NVMF_DATA_BUFFER_MASK;
2460 
2461 		opts->io_unit_size = spdk_max(opts->io_unit_size, SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
2462 		SPDK_NOTICELOG("Adjusting the io unit size to fit the device's maximum I/O size. New I/O unit size %u\n",
2463 			       opts->io_unit_size);
2464 	}
2465 
2466 	if (rc < 0) {
2467 		nvmf_rdma_destroy(&rtransport->transport);
2468 		return NULL;
2469 	}
2470 
2471 	/* Set up poll descriptor array to monitor events from RDMA and IB
2472 	 * in a single poll syscall
2473 	 */
2474 	rtransport->npoll_fds = i + 1;
2475 	i = 0;
2476 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
2477 	if (rtransport->poll_fds == NULL) {
2478 		SPDK_ERRLOG("poll_fds allocation failed\n");
2479 		nvmf_rdma_destroy(&rtransport->transport);
2480 		return NULL;
2481 	}
2482 
2483 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
2484 	rtransport->poll_fds[i++].events = POLLIN;
2485 
2486 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2487 		rtransport->poll_fds[i].fd = device->context->async_fd;
2488 		rtransport->poll_fds[i++].events = POLLIN;
2489 	}
2490 
2491 	return &rtransport->transport;
2492 }
2493 
2494 static int
2495 nvmf_rdma_destroy(struct spdk_nvmf_transport *transport)
2496 {
2497 	struct spdk_nvmf_rdma_transport	*rtransport;
2498 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
2499 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
2500 
2501 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2502 
2503 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
2504 		TAILQ_REMOVE(&rtransport->ports, port, link);
2505 		rdma_destroy_id(port->id);
2506 		free(port);
2507 	}
2508 
2509 	if (rtransport->poll_fds != NULL) {
2510 		free(rtransport->poll_fds);
2511 	}
2512 
2513 	if (rtransport->event_channel != NULL) {
2514 		rdma_destroy_event_channel(rtransport->event_channel);
2515 	}
2516 
2517 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
2518 		TAILQ_REMOVE(&rtransport->devices, device, link);
2519 		if (device->map) {
2520 			spdk_mem_map_free(&device->map);
2521 		}
2522 		if (device->pd) {
2523 			if (!g_nvmf_hooks.get_ibv_pd) {
2524 				ibv_dealloc_pd(device->pd);
2525 			}
2526 		}
2527 		free(device);
2528 	}
2529 
2530 	if (rtransport->data_wr_pool != NULL) {
2531 		if (spdk_mempool_count(rtransport->data_wr_pool) !=
2532 		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {
2533 			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",
2534 				    spdk_mempool_count(rtransport->data_wr_pool),
2535 				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);
2536 		}
2537 	}
2538 
2539 	spdk_mempool_free(rtransport->data_wr_pool);
2540 
2541 	pthread_mutex_destroy(&rtransport->lock);
2542 	free(rtransport);
2543 
2544 	return 0;
2545 }
2546 
2547 static int
2548 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2549 			  struct spdk_nvme_transport_id *trid,
2550 			  bool peer);
2551 
2552 static int
2553 nvmf_rdma_listen(struct spdk_nvmf_transport *transport,
2554 		 const struct spdk_nvme_transport_id *trid)
2555 {
2556 	struct spdk_nvmf_rdma_transport	*rtransport;
2557 	struct spdk_nvmf_rdma_device	*device;
2558 	struct spdk_nvmf_rdma_port	*port;
2559 	struct addrinfo			*res;
2560 	struct addrinfo			hints;
2561 	int				family;
2562 	int				rc;
2563 
2564 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2565 	assert(rtransport->event_channel != NULL);
2566 
2567 	pthread_mutex_lock(&rtransport->lock);
2568 	port = calloc(1, sizeof(*port));
2569 	if (!port) {
2570 		SPDK_ERRLOG("Port allocation failed\n");
2571 		pthread_mutex_unlock(&rtransport->lock);
2572 		return -ENOMEM;
2573 	}
2574 
2575 	port->trid = trid;
2576 
2577 	switch (trid->adrfam) {
2578 	case SPDK_NVMF_ADRFAM_IPV4:
2579 		family = AF_INET;
2580 		break;
2581 	case SPDK_NVMF_ADRFAM_IPV6:
2582 		family = AF_INET6;
2583 		break;
2584 	default:
2585 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", trid->adrfam);
2586 		free(port);
2587 		pthread_mutex_unlock(&rtransport->lock);
2588 		return -EINVAL;
2589 	}
2590 
2591 	memset(&hints, 0, sizeof(hints));
2592 	hints.ai_family = family;
2593 	hints.ai_flags = AI_NUMERICSERV;
2594 	hints.ai_socktype = SOCK_STREAM;
2595 	hints.ai_protocol = 0;
2596 
2597 	rc = getaddrinfo(trid->traddr, trid->trsvcid, &hints, &res);
2598 	if (rc) {
2599 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
2600 		free(port);
2601 		pthread_mutex_unlock(&rtransport->lock);
2602 		return -EINVAL;
2603 	}
2604 
2605 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
2606 	if (rc < 0) {
2607 		SPDK_ERRLOG("rdma_create_id() failed\n");
2608 		freeaddrinfo(res);
2609 		free(port);
2610 		pthread_mutex_unlock(&rtransport->lock);
2611 		return rc;
2612 	}
2613 
2614 	rc = rdma_bind_addr(port->id, res->ai_addr);
2615 	freeaddrinfo(res);
2616 
2617 	if (rc < 0) {
2618 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
2619 		rdma_destroy_id(port->id);
2620 		free(port);
2621 		pthread_mutex_unlock(&rtransport->lock);
2622 		return rc;
2623 	}
2624 
2625 	if (!port->id->verbs) {
2626 		SPDK_ERRLOG("ibv_context is null\n");
2627 		rdma_destroy_id(port->id);
2628 		free(port);
2629 		pthread_mutex_unlock(&rtransport->lock);
2630 		return -1;
2631 	}
2632 
2633 	rc = rdma_listen(port->id, transport->opts.acceptor_backlog);
2634 	if (rc < 0) {
2635 		SPDK_ERRLOG("rdma_listen() failed\n");
2636 		rdma_destroy_id(port->id);
2637 		free(port);
2638 		pthread_mutex_unlock(&rtransport->lock);
2639 		return rc;
2640 	}
2641 
2642 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2643 		if (device->context == port->id->verbs) {
2644 			port->device = device;
2645 			break;
2646 		}
2647 	}
2648 	if (!port->device) {
2649 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
2650 			    port->id->verbs);
2651 		rdma_destroy_id(port->id);
2652 		free(port);
2653 		pthread_mutex_unlock(&rtransport->lock);
2654 		return -EINVAL;
2655 	}
2656 
2657 	SPDK_NOTICELOG("*** NVMe/RDMA Target Listening on %s port %s ***\n",
2658 		       trid->traddr, trid->trsvcid);
2659 
2660 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
2661 	pthread_mutex_unlock(&rtransport->lock);
2662 	return 0;
2663 }
2664 
2665 static void
2666 nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
2667 		      const struct spdk_nvme_transport_id *trid)
2668 {
2669 	struct spdk_nvmf_rdma_transport *rtransport;
2670 	struct spdk_nvmf_rdma_port *port, *tmp;
2671 
2672 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2673 
2674 	pthread_mutex_lock(&rtransport->lock);
2675 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
2676 		if (spdk_nvme_transport_id_compare(port->trid, trid) == 0) {
2677 			TAILQ_REMOVE(&rtransport->ports, port, link);
2678 			rdma_destroy_id(port->id);
2679 			free(port);
2680 			break;
2681 		}
2682 	}
2683 
2684 	pthread_mutex_unlock(&rtransport->lock);
2685 }
2686 
2687 static void
2688 nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
2689 				struct spdk_nvmf_rdma_qpair *rqpair, bool drain)
2690 {
2691 	struct spdk_nvmf_request *req, *tmp;
2692 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
2693 	struct spdk_nvmf_rdma_resources *resources;
2694 
2695 	/* We process I/O in the data transfer pending queue at the highest priority. RDMA reads first */
2696 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_read_queue, state_link, req_tmp) {
2697 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2698 			break;
2699 		}
2700 	}
2701 
2702 	/* Then RDMA writes since reads have stronger restrictions than writes */
2703 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_write_queue, state_link, req_tmp) {
2704 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2705 			break;
2706 		}
2707 	}
2708 
2709 	/* The second highest priority is I/O waiting on memory buffers. */
2710 	STAILQ_FOREACH_SAFE(req, &rqpair->poller->group->group.pending_buf_queue, buf_link, tmp) {
2711 		rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
2712 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2713 			break;
2714 		}
2715 	}
2716 
2717 	resources = rqpair->resources;
2718 	while (!STAILQ_EMPTY(&resources->free_queue) && !STAILQ_EMPTY(&resources->incoming_queue)) {
2719 		rdma_req = STAILQ_FIRST(&resources->free_queue);
2720 		STAILQ_REMOVE_HEAD(&resources->free_queue, state_link);
2721 		rdma_req->recv = STAILQ_FIRST(&resources->incoming_queue);
2722 		STAILQ_REMOVE_HEAD(&resources->incoming_queue, link);
2723 
2724 		if (rqpair->srq != NULL) {
2725 			rdma_req->req.qpair = &rdma_req->recv->qpair->qpair;
2726 			rdma_req->recv->qpair->qd++;
2727 		} else {
2728 			rqpair->qd++;
2729 		}
2730 
2731 		rdma_req->receive_tsc = rdma_req->recv->receive_tsc;
2732 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
2733 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false) {
2734 			break;
2735 		}
2736 	}
2737 	if (!STAILQ_EMPTY(&resources->incoming_queue) && STAILQ_EMPTY(&resources->free_queue)) {
2738 		rqpair->poller->stat.pending_free_request++;
2739 	}
2740 }
2741 
2742 static void
2743 nvmf_rdma_destroy_drained_qpair(struct spdk_nvmf_rdma_qpair *rqpair)
2744 {
2745 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
2746 			struct spdk_nvmf_rdma_transport, transport);
2747 
2748 	nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
2749 
2750 	/* nvmr_rdma_close_qpair is not called */
2751 	if (!rqpair->to_close) {
2752 		return;
2753 	}
2754 
2755 	/* In non SRQ path, we will reach rqpair->max_queue_depth. In SRQ path, we will get the last_wqe event. */
2756 	if (rqpair->current_send_depth != 0) {
2757 		return;
2758 	}
2759 
2760 	if (rqpair->srq == NULL && rqpair->current_recv_depth != rqpair->max_queue_depth) {
2761 		return;
2762 	}
2763 
2764 	/* Judge whether the device is emulated by Software RoCE.
2765 	 * And it will not send last_wqe event
2766 	 */
2767 	if (rqpair->srq != NULL && rqpair->device->attr.vendor_id != 0 &&
2768 	    rqpair->last_wqe_reached == false) {
2769 		return;
2770 	}
2771 
2772 	assert(rqpair->qpair.state == SPDK_NVMF_QPAIR_ERROR);
2773 
2774 	nvmf_rdma_qpair_destroy(rqpair);
2775 }
2776 
2777 static int
2778 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
2779 {
2780 	struct spdk_nvmf_qpair		*qpair;
2781 	struct spdk_nvmf_rdma_qpair	*rqpair;
2782 
2783 	if (evt->id == NULL) {
2784 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
2785 		return -1;
2786 	}
2787 
2788 	qpair = evt->id->context;
2789 	if (qpair == NULL) {
2790 		SPDK_ERRLOG("disconnect request: no active connection\n");
2791 		return -1;
2792 	}
2793 
2794 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2795 
2796 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair->cm_id, 0);
2797 
2798 	spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2799 
2800 	return 0;
2801 }
2802 
2803 #ifdef DEBUG
2804 static const char *CM_EVENT_STR[] = {
2805 	"RDMA_CM_EVENT_ADDR_RESOLVED",
2806 	"RDMA_CM_EVENT_ADDR_ERROR",
2807 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
2808 	"RDMA_CM_EVENT_ROUTE_ERROR",
2809 	"RDMA_CM_EVENT_CONNECT_REQUEST",
2810 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
2811 	"RDMA_CM_EVENT_CONNECT_ERROR",
2812 	"RDMA_CM_EVENT_UNREACHABLE",
2813 	"RDMA_CM_EVENT_REJECTED",
2814 	"RDMA_CM_EVENT_ESTABLISHED",
2815 	"RDMA_CM_EVENT_DISCONNECTED",
2816 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
2817 	"RDMA_CM_EVENT_MULTICAST_JOIN",
2818 	"RDMA_CM_EVENT_MULTICAST_ERROR",
2819 	"RDMA_CM_EVENT_ADDR_CHANGE",
2820 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
2821 };
2822 #endif /* DEBUG */
2823 
2824 static void
2825 nvmf_rdma_disconnect_qpairs_on_port(struct spdk_nvmf_rdma_transport *rtransport,
2826 				    struct spdk_nvmf_rdma_port *port)
2827 {
2828 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2829 	struct spdk_nvmf_rdma_poller		*rpoller;
2830 	struct spdk_nvmf_rdma_qpair		*rqpair;
2831 
2832 	TAILQ_FOREACH(rgroup, &rtransport->poll_groups, link) {
2833 		TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
2834 			TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
2835 				if (rqpair->listen_id == port->id) {
2836 					spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2837 				}
2838 			}
2839 		}
2840 	}
2841 }
2842 
2843 static bool
2844 nvmf_rdma_handle_cm_event_addr_change(struct spdk_nvmf_transport *transport,
2845 				      struct rdma_cm_event *event)
2846 {
2847 	const struct spdk_nvme_transport_id	*trid;
2848 	struct spdk_nvmf_rdma_port		*port;
2849 	struct spdk_nvmf_rdma_transport		*rtransport;
2850 	bool					event_acked = false;
2851 
2852 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2853 	TAILQ_FOREACH(port, &rtransport->ports, link) {
2854 		if (port->id == event->id) {
2855 			SPDK_ERRLOG("ADDR_CHANGE: IP %s:%s migrated\n", port->trid->traddr, port->trid->trsvcid);
2856 			rdma_ack_cm_event(event);
2857 			event_acked = true;
2858 			trid = port->trid;
2859 			break;
2860 		}
2861 	}
2862 
2863 	if (event_acked) {
2864 		nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
2865 
2866 		nvmf_rdma_stop_listen(transport, trid);
2867 		nvmf_rdma_listen(transport, trid);
2868 	}
2869 
2870 	return event_acked;
2871 }
2872 
2873 static void
2874 nvmf_rdma_handle_cm_event_port_removal(struct spdk_nvmf_transport *transport,
2875 				       struct rdma_cm_event *event)
2876 {
2877 	struct spdk_nvmf_rdma_port		*port;
2878 	struct spdk_nvmf_rdma_transport		*rtransport;
2879 
2880 	port = event->id->context;
2881 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2882 
2883 	SPDK_NOTICELOG("Port %s:%s is being removed\n", port->trid->traddr, port->trid->trsvcid);
2884 
2885 	nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
2886 
2887 	rdma_ack_cm_event(event);
2888 
2889 	while (spdk_nvmf_transport_stop_listen(transport, port->trid) == 0) {
2890 		;
2891 	}
2892 }
2893 
2894 static void
2895 nvmf_process_cm_event(struct spdk_nvmf_transport *transport)
2896 {
2897 	struct spdk_nvmf_rdma_transport *rtransport;
2898 	struct rdma_cm_event		*event;
2899 	int				rc;
2900 	bool				event_acked;
2901 
2902 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2903 
2904 	if (rtransport->event_channel == NULL) {
2905 		return;
2906 	}
2907 
2908 	while (1) {
2909 		event_acked = false;
2910 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
2911 		if (rc) {
2912 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
2913 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
2914 			}
2915 			break;
2916 		}
2917 
2918 		SPDK_DEBUGLOG(rdma, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
2919 
2920 		spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
2921 
2922 		switch (event->event) {
2923 		case RDMA_CM_EVENT_ADDR_RESOLVED:
2924 		case RDMA_CM_EVENT_ADDR_ERROR:
2925 		case RDMA_CM_EVENT_ROUTE_RESOLVED:
2926 		case RDMA_CM_EVENT_ROUTE_ERROR:
2927 			/* No action required. The target never attempts to resolve routes. */
2928 			break;
2929 		case RDMA_CM_EVENT_CONNECT_REQUEST:
2930 			rc = nvmf_rdma_connect(transport, event);
2931 			if (rc < 0) {
2932 				SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
2933 				break;
2934 			}
2935 			break;
2936 		case RDMA_CM_EVENT_CONNECT_RESPONSE:
2937 			/* The target never initiates a new connection. So this will not occur. */
2938 			break;
2939 		case RDMA_CM_EVENT_CONNECT_ERROR:
2940 			/* Can this happen? The docs say it can, but not sure what causes it. */
2941 			break;
2942 		case RDMA_CM_EVENT_UNREACHABLE:
2943 		case RDMA_CM_EVENT_REJECTED:
2944 			/* These only occur on the client side. */
2945 			break;
2946 		case RDMA_CM_EVENT_ESTABLISHED:
2947 			/* TODO: Should we be waiting for this event anywhere? */
2948 			break;
2949 		case RDMA_CM_EVENT_DISCONNECTED:
2950 			rc = nvmf_rdma_disconnect(event);
2951 			if (rc < 0) {
2952 				SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2953 				break;
2954 			}
2955 			break;
2956 		case RDMA_CM_EVENT_DEVICE_REMOVAL:
2957 			/* In case of device removal, kernel IB part triggers IBV_EVENT_DEVICE_FATAL
2958 			 * which triggers RDMA_CM_EVENT_DEVICE_REMOVAL on all cma_id’s.
2959 			 * Once these events are sent to SPDK, we should release all IB resources and
2960 			 * don't make attempts to call any ibv_query/modify/create functions. We can only call
2961 			 * ibv_destory* functions to release user space memory allocated by IB. All kernel
2962 			 * resources are already cleaned. */
2963 			if (event->id->qp) {
2964 				/* If rdma_cm event has a valid `qp` pointer then the event refers to the
2965 				 * corresponding qpair. Otherwise the event refers to a listening device */
2966 				rc = nvmf_rdma_disconnect(event);
2967 				if (rc < 0) {
2968 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2969 					break;
2970 				}
2971 			} else {
2972 				nvmf_rdma_handle_cm_event_port_removal(transport, event);
2973 				event_acked = true;
2974 			}
2975 			break;
2976 		case RDMA_CM_EVENT_MULTICAST_JOIN:
2977 		case RDMA_CM_EVENT_MULTICAST_ERROR:
2978 			/* Multicast is not used */
2979 			break;
2980 		case RDMA_CM_EVENT_ADDR_CHANGE:
2981 			event_acked = nvmf_rdma_handle_cm_event_addr_change(transport, event);
2982 			break;
2983 		case RDMA_CM_EVENT_TIMEWAIT_EXIT:
2984 			/* For now, do nothing. The target never re-uses queue pairs. */
2985 			break;
2986 		default:
2987 			SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
2988 			break;
2989 		}
2990 		if (!event_acked) {
2991 			rdma_ack_cm_event(event);
2992 		}
2993 	}
2994 }
2995 
2996 static void
2997 nvmf_rdma_handle_last_wqe_reached(struct spdk_nvmf_rdma_qpair *rqpair)
2998 {
2999 	rqpair->last_wqe_reached = true;
3000 	nvmf_rdma_destroy_drained_qpair(rqpair);
3001 }
3002 
3003 static void
3004 nvmf_rdma_qpair_process_ibv_event(void *ctx)
3005 {
3006 	struct spdk_nvmf_rdma_ibv_event_ctx *event_ctx = ctx;
3007 
3008 	if (event_ctx->rqpair) {
3009 		STAILQ_REMOVE(&event_ctx->rqpair->ibv_events, event_ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3010 		if (event_ctx->cb_fn) {
3011 			event_ctx->cb_fn(event_ctx->rqpair);
3012 		}
3013 	}
3014 	free(event_ctx);
3015 }
3016 
3017 static int
3018 nvmf_rdma_send_qpair_async_event(struct spdk_nvmf_rdma_qpair *rqpair,
3019 				 spdk_nvmf_rdma_qpair_ibv_event fn)
3020 {
3021 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx;
3022 	struct spdk_thread *thr = NULL;
3023 	int rc;
3024 
3025 	if (rqpair->qpair.group) {
3026 		thr = rqpair->qpair.group->thread;
3027 	} else if (rqpair->destruct_channel) {
3028 		thr = spdk_io_channel_get_thread(rqpair->destruct_channel);
3029 	}
3030 
3031 	if (!thr) {
3032 		SPDK_DEBUGLOG(rdma, "rqpair %p has no thread\n", rqpair);
3033 		return -EINVAL;
3034 	}
3035 
3036 	ctx = calloc(1, sizeof(*ctx));
3037 	if (!ctx) {
3038 		return -ENOMEM;
3039 	}
3040 
3041 	ctx->rqpair = rqpair;
3042 	ctx->cb_fn = fn;
3043 	STAILQ_INSERT_TAIL(&rqpair->ibv_events, ctx, link);
3044 
3045 	rc = spdk_thread_send_msg(thr, nvmf_rdma_qpair_process_ibv_event, ctx);
3046 	if (rc) {
3047 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3048 		free(ctx);
3049 	}
3050 
3051 	return rc;
3052 }
3053 
3054 static int
3055 nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
3056 {
3057 	int				rc;
3058 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
3059 	struct ibv_async_event		event;
3060 
3061 	rc = ibv_get_async_event(device->context, &event);
3062 
3063 	if (rc) {
3064 		/* In non-blocking mode -1 means there are no events available */
3065 		return rc;
3066 	}
3067 
3068 	switch (event.event_type) {
3069 	case IBV_EVENT_QP_FATAL:
3070 		rqpair = event.element.qp->qp_context;
3071 		SPDK_ERRLOG("Fatal event received for rqpair %p\n", rqpair);
3072 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3073 				  (uintptr_t)rqpair->cm_id, event.event_type);
3074 		nvmf_rdma_update_ibv_state(rqpair);
3075 		spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3076 		break;
3077 	case IBV_EVENT_QP_LAST_WQE_REACHED:
3078 		/* This event only occurs for shared receive queues. */
3079 		rqpair = event.element.qp->qp_context;
3080 		SPDK_DEBUGLOG(rdma, "Last WQE reached event received for rqpair %p\n", rqpair);
3081 		rc = nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_last_wqe_reached);
3082 		if (rc) {
3083 			SPDK_WARNLOG("Failed to send LAST_WQE_REACHED event. rqpair %p, err %d\n", rqpair, rc);
3084 			rqpair->last_wqe_reached = true;
3085 		}
3086 		break;
3087 	case IBV_EVENT_SQ_DRAINED:
3088 		/* This event occurs frequently in both error and non-error states.
3089 		 * Check if the qpair is in an error state before sending a message. */
3090 		rqpair = event.element.qp->qp_context;
3091 		SPDK_DEBUGLOG(rdma, "Last sq drained event received for rqpair %p\n", rqpair);
3092 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3093 				  (uintptr_t)rqpair->cm_id, event.event_type);
3094 		if (nvmf_rdma_update_ibv_state(rqpair) == IBV_QPS_ERR) {
3095 			spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3096 		}
3097 		break;
3098 	case IBV_EVENT_QP_REQ_ERR:
3099 	case IBV_EVENT_QP_ACCESS_ERR:
3100 	case IBV_EVENT_COMM_EST:
3101 	case IBV_EVENT_PATH_MIG:
3102 	case IBV_EVENT_PATH_MIG_ERR:
3103 		SPDK_NOTICELOG("Async event: %s\n",
3104 			       ibv_event_type_str(event.event_type));
3105 		rqpair = event.element.qp->qp_context;
3106 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3107 				  (uintptr_t)rqpair->cm_id, event.event_type);
3108 		nvmf_rdma_update_ibv_state(rqpair);
3109 		break;
3110 	case IBV_EVENT_CQ_ERR:
3111 	case IBV_EVENT_DEVICE_FATAL:
3112 	case IBV_EVENT_PORT_ACTIVE:
3113 	case IBV_EVENT_PORT_ERR:
3114 	case IBV_EVENT_LID_CHANGE:
3115 	case IBV_EVENT_PKEY_CHANGE:
3116 	case IBV_EVENT_SM_CHANGE:
3117 	case IBV_EVENT_SRQ_ERR:
3118 	case IBV_EVENT_SRQ_LIMIT_REACHED:
3119 	case IBV_EVENT_CLIENT_REREGISTER:
3120 	case IBV_EVENT_GID_CHANGE:
3121 	default:
3122 		SPDK_NOTICELOG("Async event: %s\n",
3123 			       ibv_event_type_str(event.event_type));
3124 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
3125 		break;
3126 	}
3127 	ibv_ack_async_event(&event);
3128 
3129 	return 0;
3130 }
3131 
3132 static void
3133 nvmf_process_ib_events(struct spdk_nvmf_rdma_device *device, uint32_t max_events)
3134 {
3135 	int rc = 0;
3136 	uint32_t i = 0;
3137 
3138 	for (i = 0; i < max_events; i++) {
3139 		rc = nvmf_process_ib_event(device);
3140 		if (rc) {
3141 			break;
3142 		}
3143 	}
3144 
3145 	SPDK_DEBUGLOG(rdma, "Device %s: %u events processed\n", device->context->device->name, i);
3146 }
3147 
3148 static uint32_t
3149 nvmf_rdma_accept(struct spdk_nvmf_transport *transport)
3150 {
3151 	int	nfds, i = 0;
3152 	struct spdk_nvmf_rdma_transport *rtransport;
3153 	struct spdk_nvmf_rdma_device *device, *tmp;
3154 	uint32_t count;
3155 
3156 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3157 	count = nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
3158 
3159 	if (nfds <= 0) {
3160 		return 0;
3161 	}
3162 
3163 	/* The first poll descriptor is RDMA CM event */
3164 	if (rtransport->poll_fds[i++].revents & POLLIN) {
3165 		nvmf_process_cm_event(transport);
3166 		nfds--;
3167 	}
3168 
3169 	if (nfds == 0) {
3170 		return count;
3171 	}
3172 
3173 	/* Second and subsequent poll descriptors are IB async events */
3174 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
3175 		if (rtransport->poll_fds[i++].revents & POLLIN) {
3176 			nvmf_process_ib_events(device, 32);
3177 			nfds--;
3178 		}
3179 	}
3180 	/* check all flagged fd's have been served */
3181 	assert(nfds == 0);
3182 
3183 	return count;
3184 }
3185 
3186 static void
3187 nvmf_rdma_cdata_init(struct spdk_nvmf_transport *transport, struct spdk_nvmf_subsystem *subsystem,
3188 		     struct spdk_nvmf_ctrlr_data *cdata)
3189 {
3190 	cdata->nvmf_specific.msdbd = SPDK_NVMF_MAX_SGL_ENTRIES;
3191 
3192 	/* Disable in-capsule data transfer for RDMA controller when dif_insert_or_strip is enabled
3193 	since in-capsule data only works with NVME drives that support SGL memory layout */
3194 	if (transport->opts.dif_insert_or_strip) {
3195 		cdata->nvmf_specific.ioccsz = sizeof(struct spdk_nvme_cmd) / 16;
3196 	}
3197 }
3198 
3199 static void
3200 nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
3201 		   struct spdk_nvme_transport_id *trid,
3202 		   struct spdk_nvmf_discovery_log_page_entry *entry)
3203 {
3204 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
3205 	entry->adrfam = trid->adrfam;
3206 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
3207 
3208 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
3209 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
3210 
3211 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
3212 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
3213 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
3214 }
3215 
3216 static void
3217 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
3218 
3219 static struct spdk_nvmf_transport_poll_group *
3220 nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
3221 {
3222 	struct spdk_nvmf_rdma_transport		*rtransport;
3223 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3224 	struct spdk_nvmf_rdma_poller		*poller;
3225 	struct spdk_nvmf_rdma_device		*device;
3226 	struct ibv_srq_init_attr		srq_init_attr;
3227 	struct spdk_nvmf_rdma_resource_opts	opts;
3228 	int					num_cqe;
3229 
3230 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3231 
3232 	rgroup = calloc(1, sizeof(*rgroup));
3233 	if (!rgroup) {
3234 		return NULL;
3235 	}
3236 
3237 	TAILQ_INIT(&rgroup->pollers);
3238 	STAILQ_INIT(&rgroup->retired_bufs);
3239 
3240 	pthread_mutex_lock(&rtransport->lock);
3241 	TAILQ_FOREACH(device, &rtransport->devices, link) {
3242 		poller = calloc(1, sizeof(*poller));
3243 		if (!poller) {
3244 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
3245 			nvmf_rdma_poll_group_destroy(&rgroup->group);
3246 			pthread_mutex_unlock(&rtransport->lock);
3247 			return NULL;
3248 		}
3249 
3250 		poller->device = device;
3251 		poller->group = rgroup;
3252 
3253 		TAILQ_INIT(&poller->qpairs);
3254 		STAILQ_INIT(&poller->qpairs_pending_send);
3255 		STAILQ_INIT(&poller->qpairs_pending_recv);
3256 
3257 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
3258 		if (transport->opts.no_srq == false && device->num_srq < device->attr.max_srq) {
3259 			poller->max_srq_depth = transport->opts.max_srq_depth;
3260 
3261 			device->num_srq++;
3262 			memset(&srq_init_attr, 0, sizeof(struct ibv_srq_init_attr));
3263 			srq_init_attr.attr.max_wr = poller->max_srq_depth;
3264 			srq_init_attr.attr.max_sge = spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
3265 			poller->srq = ibv_create_srq(device->pd, &srq_init_attr);
3266 			if (!poller->srq) {
3267 				SPDK_ERRLOG("Unable to create shared receive queue, errno %d\n", errno);
3268 				nvmf_rdma_poll_group_destroy(&rgroup->group);
3269 				pthread_mutex_unlock(&rtransport->lock);
3270 				return NULL;
3271 			}
3272 
3273 			opts.qp = poller->srq;
3274 			opts.pd = device->pd;
3275 			opts.qpair = NULL;
3276 			opts.shared = true;
3277 			opts.max_queue_depth = poller->max_srq_depth;
3278 			opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
3279 
3280 			poller->resources = nvmf_rdma_resources_create(&opts);
3281 			if (!poller->resources) {
3282 				SPDK_ERRLOG("Unable to allocate resources for shared receive queue.\n");
3283 				nvmf_rdma_poll_group_destroy(&rgroup->group);
3284 				pthread_mutex_unlock(&rtransport->lock);
3285 				return NULL;
3286 			}
3287 		}
3288 
3289 		/*
3290 		 * When using an srq, we can limit the completion queue at startup.
3291 		 * The following formula represents the calculation:
3292 		 * num_cqe = num_recv + num_data_wr + num_send_wr.
3293 		 * where num_recv=num_data_wr=and num_send_wr=poller->max_srq_depth
3294 		 */
3295 		if (poller->srq) {
3296 			num_cqe = poller->max_srq_depth * 3;
3297 		} else {
3298 			num_cqe = DEFAULT_NVMF_RDMA_CQ_SIZE;
3299 		}
3300 
3301 		poller->cq = ibv_create_cq(device->context, num_cqe, poller, NULL, 0);
3302 		if (!poller->cq) {
3303 			SPDK_ERRLOG("Unable to create completion queue\n");
3304 			nvmf_rdma_poll_group_destroy(&rgroup->group);
3305 			pthread_mutex_unlock(&rtransport->lock);
3306 			return NULL;
3307 		}
3308 		poller->num_cqe = num_cqe;
3309 	}
3310 
3311 	TAILQ_INSERT_TAIL(&rtransport->poll_groups, rgroup, link);
3312 	if (rtransport->conn_sched.next_admin_pg == NULL) {
3313 		rtransport->conn_sched.next_admin_pg = rgroup;
3314 		rtransport->conn_sched.next_io_pg = rgroup;
3315 	}
3316 
3317 	pthread_mutex_unlock(&rtransport->lock);
3318 	return &rgroup->group;
3319 }
3320 
3321 static struct spdk_nvmf_transport_poll_group *
3322 nvmf_rdma_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
3323 {
3324 	struct spdk_nvmf_rdma_transport *rtransport;
3325 	struct spdk_nvmf_rdma_poll_group **pg;
3326 	struct spdk_nvmf_transport_poll_group *result;
3327 
3328 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
3329 
3330 	pthread_mutex_lock(&rtransport->lock);
3331 
3332 	if (TAILQ_EMPTY(&rtransport->poll_groups)) {
3333 		pthread_mutex_unlock(&rtransport->lock);
3334 		return NULL;
3335 	}
3336 
3337 	if (qpair->qid == 0) {
3338 		pg = &rtransport->conn_sched.next_admin_pg;
3339 	} else {
3340 		pg = &rtransport->conn_sched.next_io_pg;
3341 	}
3342 
3343 	assert(*pg != NULL);
3344 
3345 	result = &(*pg)->group;
3346 
3347 	*pg = TAILQ_NEXT(*pg, link);
3348 	if (*pg == NULL) {
3349 		*pg = TAILQ_FIRST(&rtransport->poll_groups);
3350 	}
3351 
3352 	pthread_mutex_unlock(&rtransport->lock);
3353 
3354 	return result;
3355 }
3356 
3357 static void
3358 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
3359 {
3360 	struct spdk_nvmf_rdma_poll_group	*rgroup, *next_rgroup;
3361 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
3362 	struct spdk_nvmf_rdma_qpair		*qpair, *tmp_qpair;
3363 	struct spdk_nvmf_transport_pg_cache_buf	*buf, *tmp_buf;
3364 	struct spdk_nvmf_rdma_transport		*rtransport;
3365 
3366 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3367 	if (!rgroup) {
3368 		return;
3369 	}
3370 
3371 	/* free all retired buffers back to the transport so we don't short the mempool. */
3372 	STAILQ_FOREACH_SAFE(buf, &rgroup->retired_bufs, link, tmp_buf) {
3373 		STAILQ_REMOVE(&rgroup->retired_bufs, buf, spdk_nvmf_transport_pg_cache_buf, link);
3374 		assert(group->transport != NULL);
3375 		spdk_mempool_put(group->transport->data_buf_pool, buf);
3376 	}
3377 
3378 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
3379 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
3380 
3381 		TAILQ_FOREACH_SAFE(qpair, &poller->qpairs, link, tmp_qpair) {
3382 			nvmf_rdma_qpair_destroy(qpair);
3383 		}
3384 
3385 		if (poller->srq) {
3386 			if (poller->resources) {
3387 				nvmf_rdma_resources_destroy(poller->resources);
3388 			}
3389 			ibv_destroy_srq(poller->srq);
3390 			SPDK_DEBUGLOG(rdma, "Destroyed RDMA shared queue %p\n", poller->srq);
3391 		}
3392 
3393 		if (poller->cq) {
3394 			ibv_destroy_cq(poller->cq);
3395 		}
3396 
3397 		free(poller);
3398 	}
3399 
3400 	if (rgroup->group.transport == NULL) {
3401 		/* Transport can be NULL when nvmf_rdma_poll_group_create()
3402 		 * calls this function directly in a failure path. */
3403 		free(rgroup);
3404 		return;
3405 	}
3406 
3407 	rtransport = SPDK_CONTAINEROF(rgroup->group.transport, struct spdk_nvmf_rdma_transport, transport);
3408 
3409 	pthread_mutex_lock(&rtransport->lock);
3410 	next_rgroup = TAILQ_NEXT(rgroup, link);
3411 	TAILQ_REMOVE(&rtransport->poll_groups, rgroup, link);
3412 	if (next_rgroup == NULL) {
3413 		next_rgroup = TAILQ_FIRST(&rtransport->poll_groups);
3414 	}
3415 	if (rtransport->conn_sched.next_admin_pg == rgroup) {
3416 		rtransport->conn_sched.next_admin_pg = next_rgroup;
3417 	}
3418 	if (rtransport->conn_sched.next_io_pg == rgroup) {
3419 		rtransport->conn_sched.next_io_pg = next_rgroup;
3420 	}
3421 	pthread_mutex_unlock(&rtransport->lock);
3422 
3423 	free(rgroup);
3424 }
3425 
3426 static void
3427 nvmf_rdma_qpair_reject_connection(struct spdk_nvmf_rdma_qpair *rqpair)
3428 {
3429 	if (rqpair->cm_id != NULL) {
3430 		nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
3431 	}
3432 }
3433 
3434 static int
3435 nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
3436 			 struct spdk_nvmf_qpair *qpair)
3437 {
3438 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3439 	struct spdk_nvmf_rdma_qpair		*rqpair;
3440 	struct spdk_nvmf_rdma_device		*device;
3441 	struct spdk_nvmf_rdma_poller		*poller;
3442 	int					rc;
3443 
3444 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3445 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3446 
3447 	device = rqpair->device;
3448 
3449 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
3450 		if (poller->device == device) {
3451 			break;
3452 		}
3453 	}
3454 
3455 	if (!poller) {
3456 		SPDK_ERRLOG("No poller found for device.\n");
3457 		return -1;
3458 	}
3459 
3460 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
3461 	rqpair->poller = poller;
3462 	rqpair->srq = rqpair->poller->srq;
3463 
3464 	rc = nvmf_rdma_qpair_initialize(qpair);
3465 	if (rc < 0) {
3466 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
3467 		return -1;
3468 	}
3469 
3470 	rc = nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
3471 	if (rc) {
3472 		/* Try to reject, but we probably can't */
3473 		nvmf_rdma_qpair_reject_connection(rqpair);
3474 		return -1;
3475 	}
3476 
3477 	nvmf_rdma_update_ibv_state(rqpair);
3478 
3479 	return 0;
3480 }
3481 
3482 static int
3483 nvmf_rdma_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
3484 			    struct spdk_nvmf_qpair *qpair)
3485 {
3486 	struct spdk_nvmf_rdma_qpair		*rqpair;
3487 
3488 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3489 	assert(group->transport->tgt != NULL);
3490 
3491 	rqpair->destruct_channel = spdk_get_io_channel(group->transport->tgt);
3492 
3493 	if (!rqpair->destruct_channel) {
3494 		SPDK_WARNLOG("failed to get io_channel, qpair %p\n", qpair);
3495 		return 0;
3496 	}
3497 
3498 	/* Sanity check that we get io_channel on the correct thread */
3499 	if (qpair->group) {
3500 		assert(qpair->group->thread == spdk_io_channel_get_thread(rqpair->destruct_channel));
3501 	}
3502 
3503 	return 0;
3504 }
3505 
3506 static int
3507 nvmf_rdma_request_free(struct spdk_nvmf_request *req)
3508 {
3509 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
3510 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3511 			struct spdk_nvmf_rdma_transport, transport);
3512 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3513 					      struct spdk_nvmf_rdma_qpair, qpair);
3514 
3515 	/*
3516 	 * AER requests are freed when a qpair is destroyed. The recv corresponding to that request
3517 	 * needs to be returned to the shared receive queue or the poll group will eventually be
3518 	 * starved of RECV structures.
3519 	 */
3520 	if (rqpair->srq && rdma_req->recv) {
3521 		int rc;
3522 		struct ibv_recv_wr *bad_recv_wr;
3523 
3524 		rc = ibv_post_srq_recv(rqpair->srq, &rdma_req->recv->wr, &bad_recv_wr);
3525 		if (rc) {
3526 			SPDK_ERRLOG("Unable to re-post rx descriptor\n");
3527 		}
3528 	}
3529 
3530 	_nvmf_rdma_request_free(rdma_req, rtransport);
3531 	return 0;
3532 }
3533 
3534 static int
3535 nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
3536 {
3537 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3538 			struct spdk_nvmf_rdma_transport, transport);
3539 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
3540 			struct spdk_nvmf_rdma_request, req);
3541 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3542 			struct spdk_nvmf_rdma_qpair, qpair);
3543 
3544 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3545 		/* The connection is alive, so process the request as normal */
3546 		rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
3547 	} else {
3548 		/* The connection is dead. Move the request directly to the completed state. */
3549 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3550 	}
3551 
3552 	nvmf_rdma_request_process(rtransport, rdma_req);
3553 
3554 	return 0;
3555 }
3556 
3557 static void
3558 nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair)
3559 {
3560 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3561 
3562 	rqpair->to_close = true;
3563 
3564 	/* This happens only when the qpair is disconnected before
3565 	 * it is added to the poll group. Since there is no poll group,
3566 	 * the RDMA qp has not been initialized yet and the RDMA CM
3567 	 * event has not yet been acknowledged, so we need to reject it.
3568 	 */
3569 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
3570 		nvmf_rdma_qpair_reject_connection(rqpair);
3571 		nvmf_rdma_qpair_destroy(rqpair);
3572 		return;
3573 	}
3574 
3575 	if (rqpair->rdma_qp) {
3576 		spdk_rdma_qp_disconnect(rqpair->rdma_qp);
3577 	}
3578 
3579 	nvmf_rdma_destroy_drained_qpair(rqpair);
3580 }
3581 
3582 static struct spdk_nvmf_rdma_qpair *
3583 get_rdma_qpair_from_wc(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_wc *wc)
3584 {
3585 	struct spdk_nvmf_rdma_qpair *rqpair;
3586 	/* @todo: improve QP search */
3587 	TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
3588 		if (wc->qp_num == rqpair->rdma_qp->qp->qp_num) {
3589 			return rqpair;
3590 		}
3591 	}
3592 	SPDK_ERRLOG("Didn't find QP with qp_num %u\n", wc->qp_num);
3593 	return NULL;
3594 }
3595 
3596 #ifdef DEBUG
3597 static int
3598 nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
3599 {
3600 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
3601 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
3602 }
3603 #endif
3604 
3605 static void
3606 _poller_reset_failed_recvs(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_recv_wr *bad_recv_wr,
3607 			   int rc)
3608 {
3609 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3610 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3611 
3612 	SPDK_ERRLOG("Failed to post a recv for the poller %p with errno %d\n", rpoller, -rc);
3613 	while (bad_recv_wr != NULL) {
3614 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_recv_wr->wr_id;
3615 		rdma_recv = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3616 
3617 		rdma_recv->qpair->current_recv_depth++;
3618 		bad_recv_wr = bad_recv_wr->next;
3619 		SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rdma_recv->qpair, -rc);
3620 		spdk_nvmf_qpair_disconnect(&rdma_recv->qpair->qpair, NULL, NULL);
3621 	}
3622 }
3623 
3624 static void
3625 _qp_reset_failed_recvs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *bad_recv_wr, int rc)
3626 {
3627 	SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rqpair, -rc);
3628 	while (bad_recv_wr != NULL) {
3629 		bad_recv_wr = bad_recv_wr->next;
3630 		rqpair->current_recv_depth++;
3631 	}
3632 	spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3633 }
3634 
3635 static void
3636 _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
3637 		     struct spdk_nvmf_rdma_poller *rpoller)
3638 {
3639 	struct spdk_nvmf_rdma_qpair	*rqpair;
3640 	struct ibv_recv_wr		*bad_recv_wr;
3641 	int				rc;
3642 
3643 	if (rpoller->srq) {
3644 		if (rpoller->resources->recvs_to_post.first != NULL) {
3645 			rc = ibv_post_srq_recv(rpoller->srq, rpoller->resources->recvs_to_post.first, &bad_recv_wr);
3646 			if (rc) {
3647 				_poller_reset_failed_recvs(rpoller, bad_recv_wr, rc);
3648 			}
3649 			rpoller->resources->recvs_to_post.first = NULL;
3650 			rpoller->resources->recvs_to_post.last = NULL;
3651 		}
3652 	} else {
3653 		while (!STAILQ_EMPTY(&rpoller->qpairs_pending_recv)) {
3654 			rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_recv);
3655 			assert(rqpair->resources->recvs_to_post.first != NULL);
3656 			rc = ibv_post_recv(rqpair->rdma_qp->qp, rqpair->resources->recvs_to_post.first, &bad_recv_wr);
3657 			if (rc) {
3658 				_qp_reset_failed_recvs(rqpair, bad_recv_wr, rc);
3659 			}
3660 			rqpair->resources->recvs_to_post.first = NULL;
3661 			rqpair->resources->recvs_to_post.last = NULL;
3662 			STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_recv, recv_link);
3663 		}
3664 	}
3665 }
3666 
3667 static void
3668 _qp_reset_failed_sends(struct spdk_nvmf_rdma_transport *rtransport,
3669 		       struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_send_wr *bad_wr, int rc)
3670 {
3671 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3672 	struct spdk_nvmf_rdma_request	*prev_rdma_req = NULL, *cur_rdma_req = NULL;
3673 
3674 	SPDK_ERRLOG("Failed to post a send for the qpair %p with errno %d\n", rqpair, -rc);
3675 	for (; bad_wr != NULL; bad_wr = bad_wr->next) {
3676 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_wr->wr_id;
3677 		assert(rqpair->current_send_depth > 0);
3678 		rqpair->current_send_depth--;
3679 		switch (bad_rdma_wr->type) {
3680 		case RDMA_WR_TYPE_DATA:
3681 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3682 			if (bad_wr->opcode == IBV_WR_RDMA_READ) {
3683 				assert(rqpair->current_read_depth > 0);
3684 				rqpair->current_read_depth--;
3685 			}
3686 			break;
3687 		case RDMA_WR_TYPE_SEND:
3688 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3689 			break;
3690 		default:
3691 			SPDK_ERRLOG("Found a RECV in the list of pending SEND requests for qpair %p\n", rqpair);
3692 			prev_rdma_req = cur_rdma_req;
3693 			continue;
3694 		}
3695 
3696 		if (prev_rdma_req == cur_rdma_req) {
3697 			/* this request was handled by an earlier wr. i.e. we were performing an nvme read. */
3698 			/* We only have to check against prev_wr since each requests wrs are contiguous in this list. */
3699 			continue;
3700 		}
3701 
3702 		switch (cur_rdma_req->state) {
3703 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
3704 			cur_rdma_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
3705 			cur_rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
3706 			break;
3707 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
3708 		case RDMA_REQUEST_STATE_COMPLETING:
3709 			cur_rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3710 			break;
3711 		default:
3712 			SPDK_ERRLOG("Found a request in a bad state %d when draining pending SEND requests for qpair %p\n",
3713 				    cur_rdma_req->state, rqpair);
3714 			continue;
3715 		}
3716 
3717 		nvmf_rdma_request_process(rtransport, cur_rdma_req);
3718 		prev_rdma_req = cur_rdma_req;
3719 	}
3720 
3721 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3722 		/* Disconnect the connection. */
3723 		spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3724 	}
3725 
3726 }
3727 
3728 static void
3729 _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
3730 		     struct spdk_nvmf_rdma_poller *rpoller)
3731 {
3732 	struct spdk_nvmf_rdma_qpair	*rqpair;
3733 	struct ibv_send_wr		*bad_wr = NULL;
3734 	int				rc;
3735 
3736 	while (!STAILQ_EMPTY(&rpoller->qpairs_pending_send)) {
3737 		rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_send);
3738 		rc = spdk_rdma_qp_flush_send_wrs(rqpair->rdma_qp, &bad_wr);
3739 
3740 		/* bad wr always points to the first wr that failed. */
3741 		if (rc) {
3742 			_qp_reset_failed_sends(rtransport, rqpair, bad_wr, rc);
3743 		}
3744 		STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_send, send_link);
3745 	}
3746 }
3747 
3748 static const char *
3749 nvmf_rdma_wr_type_str(enum spdk_nvmf_rdma_wr_type wr_type)
3750 {
3751 	switch (wr_type) {
3752 	case RDMA_WR_TYPE_RECV:
3753 		return "RECV";
3754 	case RDMA_WR_TYPE_SEND:
3755 		return "SEND";
3756 	case RDMA_WR_TYPE_DATA:
3757 		return "DATA";
3758 	default:
3759 		SPDK_ERRLOG("Unknown WR type %d\n", wr_type);
3760 		SPDK_UNREACHABLE();
3761 	}
3762 }
3763 
3764 static inline void
3765 nvmf_rdma_log_wc_status(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_wc *wc)
3766 {
3767 	enum spdk_nvmf_rdma_wr_type wr_type = ((struct spdk_nvmf_rdma_wr *)wc->wr_id)->type;
3768 
3769 	if (wc->status == IBV_WC_WR_FLUSH_ERR) {
3770 		/* If qpair is in ERR state, we will receive completions for all posted and not completed
3771 		 * Work Requests with IBV_WC_WR_FLUSH_ERR status. Don't log an error in that case */
3772 		SPDK_DEBUGLOG(rdma,
3773 			      "Error on CQ %p, (qp state %d ibv_state %d) request 0x%lu, type %s, status: (%d): %s\n",
3774 			      rqpair->poller->cq, rqpair->qpair.state, rqpair->ibv_state, wc->wr_id,
3775 			      nvmf_rdma_wr_type_str(wr_type), wc->status, ibv_wc_status_str(wc->status));
3776 	} else {
3777 		SPDK_ERRLOG("Error on CQ %p, (qp state %d ibv_state %d) request 0x%lu, type %s, status: (%d): %s\n",
3778 			    rqpair->poller->cq, rqpair->qpair.state, rqpair->ibv_state, wc->wr_id,
3779 			    nvmf_rdma_wr_type_str(wr_type), wc->status, ibv_wc_status_str(wc->status));
3780 	}
3781 }
3782 
3783 static int
3784 nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
3785 		      struct spdk_nvmf_rdma_poller *rpoller)
3786 {
3787 	struct ibv_wc wc[32];
3788 	struct spdk_nvmf_rdma_wr	*rdma_wr;
3789 	struct spdk_nvmf_rdma_request	*rdma_req;
3790 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3791 	struct spdk_nvmf_rdma_qpair	*rqpair;
3792 	int reaped, i;
3793 	int count = 0;
3794 	bool error = false;
3795 	uint64_t poll_tsc = spdk_get_ticks();
3796 
3797 	/* Poll for completing operations. */
3798 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
3799 	if (reaped < 0) {
3800 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
3801 			    errno, spdk_strerror(errno));
3802 		return -1;
3803 	}
3804 
3805 	rpoller->stat.polls++;
3806 	rpoller->stat.completions += reaped;
3807 
3808 	for (i = 0; i < reaped; i++) {
3809 
3810 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
3811 
3812 		switch (rdma_wr->type) {
3813 		case RDMA_WR_TYPE_SEND:
3814 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3815 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3816 
3817 			if (!wc[i].status) {
3818 				count++;
3819 				assert(wc[i].opcode == IBV_WC_SEND);
3820 				assert(nvmf_rdma_req_is_completing(rdma_req));
3821 			}
3822 
3823 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3824 			/* RDMA_WRITE operation completed. +1 since it was chained with rsp WR */
3825 			rqpair->current_send_depth -= rdma_req->num_outstanding_data_wr + 1;
3826 			rdma_req->num_outstanding_data_wr = 0;
3827 
3828 			nvmf_rdma_request_process(rtransport, rdma_req);
3829 			break;
3830 		case RDMA_WR_TYPE_RECV:
3831 			/* rdma_recv->qpair will be invalid if using an SRQ.  In that case we have to get the qpair from the wc. */
3832 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3833 			if (rpoller->srq != NULL) {
3834 				rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
3835 				/* It is possible that there are still some completions for destroyed QP
3836 				 * associated with SRQ. We just ignore these late completions and re-post
3837 				 * receive WRs back to SRQ.
3838 				 */
3839 				if (spdk_unlikely(NULL == rdma_recv->qpair)) {
3840 					struct ibv_recv_wr *bad_wr;
3841 					int rc;
3842 
3843 					rdma_recv->wr.next = NULL;
3844 					rc = ibv_post_srq_recv(rpoller->srq,
3845 							       &rdma_recv->wr,
3846 							       &bad_wr);
3847 					if (rc) {
3848 						SPDK_ERRLOG("Failed to re-post recv WR to SRQ, err %d\n", rc);
3849 					}
3850 					continue;
3851 				}
3852 			}
3853 			rqpair = rdma_recv->qpair;
3854 
3855 			assert(rqpair != NULL);
3856 			if (!wc[i].status) {
3857 				assert(wc[i].opcode == IBV_WC_RECV);
3858 				if (rqpair->current_recv_depth >= rqpair->max_queue_depth) {
3859 					spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3860 					break;
3861 				}
3862 			}
3863 
3864 			rdma_recv->wr.next = NULL;
3865 			rqpair->current_recv_depth++;
3866 			rdma_recv->receive_tsc = poll_tsc;
3867 			rpoller->stat.requests++;
3868 			STAILQ_INSERT_TAIL(&rqpair->resources->incoming_queue, rdma_recv, link);
3869 			break;
3870 		case RDMA_WR_TYPE_DATA:
3871 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3872 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3873 
3874 			assert(rdma_req->num_outstanding_data_wr > 0);
3875 
3876 			rqpair->current_send_depth--;
3877 			rdma_req->num_outstanding_data_wr--;
3878 			if (!wc[i].status) {
3879 				assert(wc[i].opcode == IBV_WC_RDMA_READ);
3880 				rqpair->current_read_depth--;
3881 				/* wait for all outstanding reads associated with the same rdma_req to complete before proceeding. */
3882 				if (rdma_req->num_outstanding_data_wr == 0) {
3883 					rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
3884 					nvmf_rdma_request_process(rtransport, rdma_req);
3885 				}
3886 			} else {
3887 				/* If the data transfer fails still force the queue into the error state,
3888 				 * if we were performing an RDMA_READ, we need to force the request into a
3889 				 * completed state since it wasn't linked to a send. However, in the RDMA_WRITE
3890 				 * case, we should wait for the SEND to complete. */
3891 				if (rdma_req->data.wr.opcode == IBV_WR_RDMA_READ) {
3892 					rqpair->current_read_depth--;
3893 					if (rdma_req->num_outstanding_data_wr == 0) {
3894 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3895 					}
3896 				}
3897 			}
3898 			break;
3899 		default:
3900 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
3901 			continue;
3902 		}
3903 
3904 		/* Handle error conditions */
3905 		if (wc[i].status) {
3906 			nvmf_rdma_update_ibv_state(rqpair);
3907 			nvmf_rdma_log_wc_status(rqpair, &wc[i]);
3908 
3909 			error = true;
3910 
3911 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3912 				/* Disconnect the connection. */
3913 				spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3914 			} else {
3915 				nvmf_rdma_destroy_drained_qpair(rqpair);
3916 			}
3917 			continue;
3918 		}
3919 
3920 		nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3921 
3922 		if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
3923 			nvmf_rdma_destroy_drained_qpair(rqpair);
3924 		}
3925 	}
3926 
3927 	if (error == true) {
3928 		return -1;
3929 	}
3930 
3931 	/* submit outstanding work requests. */
3932 	_poller_submit_recvs(rtransport, rpoller);
3933 	_poller_submit_sends(rtransport, rpoller);
3934 
3935 	return count;
3936 }
3937 
3938 static int
3939 nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3940 {
3941 	struct spdk_nvmf_rdma_transport *rtransport;
3942 	struct spdk_nvmf_rdma_poll_group *rgroup;
3943 	struct spdk_nvmf_rdma_poller	*rpoller;
3944 	int				count, rc;
3945 
3946 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
3947 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3948 
3949 	count = 0;
3950 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3951 		rc = nvmf_rdma_poller_poll(rtransport, rpoller);
3952 		if (rc < 0) {
3953 			return rc;
3954 		}
3955 		count += rc;
3956 	}
3957 
3958 	return count;
3959 }
3960 
3961 static int
3962 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
3963 			  struct spdk_nvme_transport_id *trid,
3964 			  bool peer)
3965 {
3966 	struct sockaddr *saddr;
3967 	uint16_t port;
3968 
3969 	spdk_nvme_trid_populate_transport(trid, SPDK_NVME_TRANSPORT_RDMA);
3970 
3971 	if (peer) {
3972 		saddr = rdma_get_peer_addr(id);
3973 	} else {
3974 		saddr = rdma_get_local_addr(id);
3975 	}
3976 	switch (saddr->sa_family) {
3977 	case AF_INET: {
3978 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
3979 
3980 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3981 		inet_ntop(AF_INET, &saddr_in->sin_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 	case AF_INET6: {
3992 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
3993 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3994 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
3995 			  trid->traddr, sizeof(trid->traddr));
3996 		if (peer) {
3997 			port = ntohs(rdma_get_dst_port(id));
3998 		} else {
3999 			port = ntohs(rdma_get_src_port(id));
4000 		}
4001 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
4002 		break;
4003 	}
4004 	default:
4005 		return -1;
4006 
4007 	}
4008 
4009 	return 0;
4010 }
4011 
4012 static int
4013 nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
4014 			      struct spdk_nvme_transport_id *trid)
4015 {
4016 	struct spdk_nvmf_rdma_qpair	*rqpair;
4017 
4018 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4019 
4020 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
4021 }
4022 
4023 static int
4024 nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
4025 			       struct spdk_nvme_transport_id *trid)
4026 {
4027 	struct spdk_nvmf_rdma_qpair	*rqpair;
4028 
4029 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4030 
4031 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
4032 }
4033 
4034 static int
4035 nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
4036 				struct spdk_nvme_transport_id *trid)
4037 {
4038 	struct spdk_nvmf_rdma_qpair	*rqpair;
4039 
4040 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4041 
4042 	return nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
4043 }
4044 
4045 void
4046 spdk_nvmf_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
4047 {
4048 	g_nvmf_hooks = *hooks;
4049 }
4050 
4051 static void
4052 nvmf_rdma_request_set_abort_status(struct spdk_nvmf_request *req,
4053 				   struct spdk_nvmf_rdma_request *rdma_req_to_abort)
4054 {
4055 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
4056 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_BY_REQUEST;
4057 
4058 	rdma_req_to_abort->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
4059 
4060 	req->rsp->nvme_cpl.cdw0 &= ~1U;	/* Command was successfully aborted. */
4061 }
4062 
4063 static int
4064 _nvmf_rdma_qpair_abort_request(void *ctx)
4065 {
4066 	struct spdk_nvmf_request *req = ctx;
4067 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = SPDK_CONTAINEROF(
4068 				req->req_to_abort, struct spdk_nvmf_rdma_request, req);
4069 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(req->req_to_abort->qpair,
4070 					      struct spdk_nvmf_rdma_qpair, qpair);
4071 	int rc;
4072 
4073 	spdk_poller_unregister(&req->poller);
4074 
4075 	switch (rdma_req_to_abort->state) {
4076 	case RDMA_REQUEST_STATE_EXECUTING:
4077 		rc = nvmf_ctrlr_abort_request(req);
4078 		if (rc == SPDK_NVMF_REQUEST_EXEC_STATUS_ASYNCHRONOUS) {
4079 			return SPDK_POLLER_BUSY;
4080 		}
4081 		break;
4082 
4083 	case RDMA_REQUEST_STATE_NEED_BUFFER:
4084 		STAILQ_REMOVE(&rqpair->poller->group->group.pending_buf_queue,
4085 			      &rdma_req_to_abort->req, spdk_nvmf_request, buf_link);
4086 
4087 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4088 		break;
4089 
4090 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
4091 		STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req_to_abort,
4092 			      spdk_nvmf_rdma_request, state_link);
4093 
4094 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4095 		break;
4096 
4097 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
4098 		STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req_to_abort,
4099 			      spdk_nvmf_rdma_request, state_link);
4100 
4101 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4102 		break;
4103 
4104 	case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
4105 		if (spdk_get_ticks() < req->timeout_tsc) {
4106 			req->poller = SPDK_POLLER_REGISTER(_nvmf_rdma_qpair_abort_request, req, 0);
4107 			return SPDK_POLLER_BUSY;
4108 		}
4109 		break;
4110 
4111 	default:
4112 		break;
4113 	}
4114 
4115 	spdk_nvmf_request_complete(req);
4116 	return SPDK_POLLER_BUSY;
4117 }
4118 
4119 static void
4120 nvmf_rdma_qpair_abort_request(struct spdk_nvmf_qpair *qpair,
4121 			      struct spdk_nvmf_request *req)
4122 {
4123 	struct spdk_nvmf_rdma_qpair *rqpair;
4124 	struct spdk_nvmf_rdma_transport *rtransport;
4125 	struct spdk_nvmf_transport *transport;
4126 	uint16_t cid;
4127 	uint32_t i;
4128 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = NULL;
4129 
4130 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4131 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
4132 	transport = &rtransport->transport;
4133 
4134 	cid = req->cmd->nvme_cmd.cdw10_bits.abort.cid;
4135 
4136 	for (i = 0; i < rqpair->max_queue_depth; i++) {
4137 		rdma_req_to_abort = &rqpair->resources->reqs[i];
4138 
4139 		if (rdma_req_to_abort->state != RDMA_REQUEST_STATE_FREE &&
4140 		    rdma_req_to_abort->req.cmd->nvme_cmd.cid == cid) {
4141 			break;
4142 		}
4143 	}
4144 
4145 	if (rdma_req_to_abort == NULL) {
4146 		spdk_nvmf_request_complete(req);
4147 		return;
4148 	}
4149 
4150 	req->req_to_abort = &rdma_req_to_abort->req;
4151 	req->timeout_tsc = spdk_get_ticks() +
4152 			   transport->opts.abort_timeout_sec * spdk_get_ticks_hz();
4153 	req->poller = NULL;
4154 
4155 	_nvmf_rdma_qpair_abort_request(req);
4156 }
4157 
4158 static int
4159 nvmf_rdma_poll_group_get_stat(struct spdk_nvmf_tgt *tgt,
4160 			      struct spdk_nvmf_transport_poll_group_stat **stat)
4161 {
4162 	struct spdk_io_channel *ch;
4163 	struct spdk_nvmf_poll_group *group;
4164 	struct spdk_nvmf_transport_poll_group *tgroup;
4165 	struct spdk_nvmf_rdma_poll_group *rgroup;
4166 	struct spdk_nvmf_rdma_poller *rpoller;
4167 	struct spdk_nvmf_rdma_device_stat *device_stat;
4168 	uint64_t num_devices = 0;
4169 
4170 	if (tgt == NULL || stat == NULL) {
4171 		return -EINVAL;
4172 	}
4173 
4174 	ch = spdk_get_io_channel(tgt);
4175 	group = spdk_io_channel_get_ctx(ch);;
4176 	spdk_put_io_channel(ch);
4177 	TAILQ_FOREACH(tgroup, &group->tgroups, link) {
4178 		if (SPDK_NVME_TRANSPORT_RDMA == tgroup->transport->ops->type) {
4179 			*stat = calloc(1, sizeof(struct spdk_nvmf_transport_poll_group_stat));
4180 			if (!*stat) {
4181 				SPDK_ERRLOG("Failed to allocate memory for NVMf RDMA statistics\n");
4182 				return -ENOMEM;
4183 			}
4184 			(*stat)->trtype = SPDK_NVME_TRANSPORT_RDMA;
4185 
4186 			rgroup = SPDK_CONTAINEROF(tgroup, struct spdk_nvmf_rdma_poll_group, group);
4187 			/* Count devices to allocate enough memory */
4188 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4189 				++num_devices;
4190 			}
4191 			(*stat)->rdma.devices = calloc(num_devices, sizeof(struct spdk_nvmf_rdma_device_stat));
4192 			if (!(*stat)->rdma.devices) {
4193 				SPDK_ERRLOG("Failed to allocate NVMf RDMA devices statistics\n");
4194 				free(*stat);
4195 				return -ENOMEM;
4196 			}
4197 
4198 			(*stat)->rdma.pending_data_buffer = rgroup->stat.pending_data_buffer;
4199 			(*stat)->rdma.num_devices = num_devices;
4200 			num_devices = 0;
4201 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4202 				device_stat = &(*stat)->rdma.devices[num_devices++];
4203 				device_stat->name = ibv_get_device_name(rpoller->device->context->device);
4204 				device_stat->polls = rpoller->stat.polls;
4205 				device_stat->completions = rpoller->stat.completions;
4206 				device_stat->requests = rpoller->stat.requests;
4207 				device_stat->request_latency = rpoller->stat.request_latency;
4208 				device_stat->pending_free_request = rpoller->stat.pending_free_request;
4209 				device_stat->pending_rdma_read = rpoller->stat.pending_rdma_read;
4210 				device_stat->pending_rdma_write = rpoller->stat.pending_rdma_write;
4211 			}
4212 			return 0;
4213 		}
4214 	}
4215 	return -ENOENT;
4216 }
4217 
4218 static void
4219 nvmf_rdma_poll_group_free_stat(struct spdk_nvmf_transport_poll_group_stat *stat)
4220 {
4221 	if (stat) {
4222 		free(stat->rdma.devices);
4223 	}
4224 	free(stat);
4225 }
4226 
4227 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
4228 	.name = "RDMA",
4229 	.type = SPDK_NVME_TRANSPORT_RDMA,
4230 	.opts_init = nvmf_rdma_opts_init,
4231 	.create = nvmf_rdma_create,
4232 	.destroy = nvmf_rdma_destroy,
4233 
4234 	.listen = nvmf_rdma_listen,
4235 	.stop_listen = nvmf_rdma_stop_listen,
4236 	.accept = nvmf_rdma_accept,
4237 	.cdata_init = nvmf_rdma_cdata_init,
4238 
4239 	.listener_discover = nvmf_rdma_discover,
4240 
4241 	.poll_group_create = nvmf_rdma_poll_group_create,
4242 	.get_optimal_poll_group = nvmf_rdma_get_optimal_poll_group,
4243 	.poll_group_destroy = nvmf_rdma_poll_group_destroy,
4244 	.poll_group_add = nvmf_rdma_poll_group_add,
4245 	.poll_group_remove = nvmf_rdma_poll_group_remove,
4246 	.poll_group_poll = nvmf_rdma_poll_group_poll,
4247 
4248 	.req_free = nvmf_rdma_request_free,
4249 	.req_complete = nvmf_rdma_request_complete,
4250 
4251 	.qpair_fini = nvmf_rdma_close_qpair,
4252 	.qpair_get_peer_trid = nvmf_rdma_qpair_get_peer_trid,
4253 	.qpair_get_local_trid = nvmf_rdma_qpair_get_local_trid,
4254 	.qpair_get_listen_trid = nvmf_rdma_qpair_get_listen_trid,
4255 	.qpair_abort_request = nvmf_rdma_qpair_abort_request,
4256 
4257 	.poll_group_get_stat = nvmf_rdma_poll_group_get_stat,
4258 	.poll_group_free_stat = nvmf_rdma_poll_group_free_stat,
4259 };
4260 
4261 SPDK_NVMF_TRANSPORT_REGISTER(rdma, &spdk_nvmf_transport_rdma);
4262 SPDK_LOG_REGISTER_COMPONENT(rdma)
4263