xref: /spdk/lib/nvmf/rdma.c (revision 0ed85362c8132a2d1927757fbcade66b6660d26a)
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_internal/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(SPDK_LOG_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(SPDK_LOG_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(SPDK_LOG_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(SPDK_LOG_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(SPDK_LOG_RDMA, "Resize RDMA CQ from %d to %d\n", rpoller->num_cqe, num_cqe);
920 		rc = ibv_resize_cq(rpoller->cq, num_cqe);
921 		if (rc) {
922 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
923 			return -1;
924 		}
925 
926 		rpoller->num_cqe = num_cqe;
927 	}
928 
929 	rpoller->required_num_wr = required_num_wr;
930 	return 0;
931 }
932 
933 static int
934 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(SPDK_LOG_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(SPDK_LOG_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(SPDK_LOG_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(SPDK_LOG_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(SPDK_LOG_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(SPDK_LOG_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(SPDK_LOG_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(SPDK_LOG_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(SPDK_LOG_RDMA, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1244 		SPDK_DEBUGLOG(SPDK_LOG_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(SPDK_LOG_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 	STAILQ_INIT(&rqpair->ibv_events);
1266 	/* use qid from the private data to determine the qpair type
1267 	   qid will be set to the appropriate value when the controller is created */
1268 	rqpair->qpair.qid = private_data->qid;
1269 
1270 	event->id->context = &rqpair->qpair;
1271 
1272 	spdk_nvmf_tgt_new_qpair(transport->tgt, &rqpair->qpair);
1273 
1274 	return 0;
1275 }
1276 
1277 static int
1278 nvmf_rdma_mem_notify(void *cb_ctx, struct spdk_mem_map *map,
1279 		     enum spdk_mem_map_notify_action action,
1280 		     void *vaddr, size_t size)
1281 {
1282 	struct ibv_pd *pd = cb_ctx;
1283 	struct ibv_mr *mr;
1284 	int rc;
1285 
1286 	switch (action) {
1287 	case SPDK_MEM_MAP_NOTIFY_REGISTER:
1288 		if (!g_nvmf_hooks.get_rkey) {
1289 			mr = ibv_reg_mr(pd, vaddr, size,
1290 					IBV_ACCESS_LOCAL_WRITE |
1291 					IBV_ACCESS_REMOTE_READ |
1292 					IBV_ACCESS_REMOTE_WRITE);
1293 			if (mr == NULL) {
1294 				SPDK_ERRLOG("ibv_reg_mr() failed\n");
1295 				return -1;
1296 			} else {
1297 				rc = spdk_mem_map_set_translation(map, (uint64_t)vaddr, size, (uint64_t)mr);
1298 			}
1299 		} else {
1300 			rc = spdk_mem_map_set_translation(map, (uint64_t)vaddr, size,
1301 							  g_nvmf_hooks.get_rkey(pd, vaddr, size));
1302 		}
1303 		break;
1304 	case SPDK_MEM_MAP_NOTIFY_UNREGISTER:
1305 		if (!g_nvmf_hooks.get_rkey) {
1306 			mr = (struct ibv_mr *)spdk_mem_map_translate(map, (uint64_t)vaddr, NULL);
1307 			if (mr) {
1308 				ibv_dereg_mr(mr);
1309 			}
1310 		}
1311 		rc = spdk_mem_map_clear_translation(map, (uint64_t)vaddr, size);
1312 		break;
1313 	default:
1314 		SPDK_UNREACHABLE();
1315 	}
1316 
1317 	return rc;
1318 }
1319 
1320 static int
1321 nvmf_rdma_check_contiguous_entries(uint64_t addr_1, uint64_t addr_2)
1322 {
1323 	/* Two contiguous mappings will point to the same address which is the start of the RDMA MR. */
1324 	return addr_1 == addr_2;
1325 }
1326 
1327 static inline void
1328 nvmf_rdma_setup_wr(struct ibv_send_wr *wr, struct ibv_send_wr *next,
1329 		   enum spdk_nvme_data_transfer xfer)
1330 {
1331 	if (xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1332 		wr->opcode = IBV_WR_RDMA_WRITE;
1333 		wr->send_flags = 0;
1334 		wr->next = next;
1335 	} else if (xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1336 		wr->opcode = IBV_WR_RDMA_READ;
1337 		wr->send_flags = IBV_SEND_SIGNALED;
1338 		wr->next = NULL;
1339 	} else {
1340 		assert(0);
1341 	}
1342 }
1343 
1344 static int
1345 nvmf_request_alloc_wrs(struct spdk_nvmf_rdma_transport *rtransport,
1346 		       struct spdk_nvmf_rdma_request *rdma_req,
1347 		       uint32_t num_sgl_descriptors)
1348 {
1349 	struct spdk_nvmf_rdma_request_data	*work_requests[SPDK_NVMF_MAX_SGL_ENTRIES];
1350 	struct spdk_nvmf_rdma_request_data	*current_data_wr;
1351 	uint32_t				i;
1352 
1353 	if (num_sgl_descriptors > SPDK_NVMF_MAX_SGL_ENTRIES) {
1354 		SPDK_ERRLOG("Requested too much entries (%u), the limit is %u\n",
1355 			    num_sgl_descriptors, SPDK_NVMF_MAX_SGL_ENTRIES);
1356 		return -EINVAL;
1357 	}
1358 
1359 	if (spdk_mempool_get_bulk(rtransport->data_wr_pool, (void **)work_requests, num_sgl_descriptors)) {
1360 		return -ENOMEM;
1361 	}
1362 
1363 	current_data_wr = &rdma_req->data;
1364 
1365 	for (i = 0; i < num_sgl_descriptors; i++) {
1366 		nvmf_rdma_setup_wr(&current_data_wr->wr, &work_requests[i]->wr, rdma_req->req.xfer);
1367 		current_data_wr->wr.next = &work_requests[i]->wr;
1368 		current_data_wr = work_requests[i];
1369 		current_data_wr->wr.sg_list = current_data_wr->sgl;
1370 		current_data_wr->wr.wr_id = rdma_req->data.wr.wr_id;
1371 	}
1372 
1373 	nvmf_rdma_setup_wr(&current_data_wr->wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1374 
1375 	return 0;
1376 }
1377 
1378 static inline void
1379 nvmf_rdma_setup_request(struct spdk_nvmf_rdma_request *rdma_req)
1380 {
1381 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1382 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1383 
1384 	wr->wr.rdma.rkey = sgl->keyed.key;
1385 	wr->wr.rdma.remote_addr = sgl->address;
1386 	nvmf_rdma_setup_wr(wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1387 }
1388 
1389 static inline void
1390 nvmf_rdma_update_remote_addr(struct spdk_nvmf_rdma_request *rdma_req, uint32_t num_wrs)
1391 {
1392 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1393 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1394 	uint32_t			i;
1395 	int				j;
1396 	uint64_t			remote_addr_offset = 0;
1397 
1398 	for (i = 0; i < num_wrs; ++i) {
1399 		wr->wr.rdma.rkey = sgl->keyed.key;
1400 		wr->wr.rdma.remote_addr = sgl->address + remote_addr_offset;
1401 		for (j = 0; j < wr->num_sge; ++j) {
1402 			remote_addr_offset += wr->sg_list[j].length;
1403 		}
1404 		wr = wr->next;
1405 	}
1406 }
1407 
1408 /* This function is used in the rare case that we have a buffer split over multiple memory regions. */
1409 static int
1410 nvmf_rdma_replace_buffer(struct spdk_nvmf_rdma_poll_group *rgroup, void **buf)
1411 {
1412 	struct spdk_nvmf_transport_poll_group	*group = &rgroup->group;
1413 	struct spdk_nvmf_transport		*transport = group->transport;
1414 	struct spdk_nvmf_transport_pg_cache_buf	*old_buf;
1415 	void					*new_buf;
1416 
1417 	if (!(STAILQ_EMPTY(&group->buf_cache))) {
1418 		group->buf_cache_count--;
1419 		new_buf = STAILQ_FIRST(&group->buf_cache);
1420 		STAILQ_REMOVE_HEAD(&group->buf_cache, link);
1421 		assert(*buf != NULL);
1422 	} else {
1423 		new_buf = spdk_mempool_get(transport->data_buf_pool);
1424 	}
1425 
1426 	if (*buf == NULL) {
1427 		return -ENOMEM;
1428 	}
1429 
1430 	old_buf = *buf;
1431 	STAILQ_INSERT_HEAD(&rgroup->retired_bufs, old_buf, link);
1432 	*buf = new_buf;
1433 	return 0;
1434 }
1435 
1436 static bool
1437 nvmf_rdma_get_lkey(struct spdk_nvmf_rdma_device *device, struct iovec *iov,
1438 		   uint32_t *_lkey)
1439 {
1440 	uint64_t	translation_len;
1441 	uint32_t	lkey;
1442 
1443 	translation_len = iov->iov_len;
1444 
1445 	if (!g_nvmf_hooks.get_rkey) {
1446 		lkey = ((struct ibv_mr *)spdk_mem_map_translate(device->map,
1447 				(uint64_t)iov->iov_base, &translation_len))->lkey;
1448 	} else {
1449 		lkey = spdk_mem_map_translate(device->map,
1450 					      (uint64_t)iov->iov_base, &translation_len);
1451 	}
1452 
1453 	if (spdk_unlikely(translation_len < iov->iov_len)) {
1454 		return false;
1455 	}
1456 
1457 	*_lkey = lkey;
1458 	return true;
1459 }
1460 
1461 static bool
1462 nvmf_rdma_fill_wr_sge(struct spdk_nvmf_rdma_device *device,
1463 		      struct iovec *iov, struct ibv_send_wr **_wr,
1464 		      uint32_t *_remaining_data_block, uint32_t *_offset,
1465 		      uint32_t *_num_extra_wrs,
1466 		      const struct spdk_dif_ctx *dif_ctx)
1467 {
1468 	struct ibv_send_wr *wr = *_wr;
1469 	struct ibv_sge	*sg_ele = &wr->sg_list[wr->num_sge];
1470 	uint32_t	lkey = 0;
1471 	uint32_t	remaining, data_block_size, md_size, sge_len;
1472 
1473 	if (spdk_unlikely(!nvmf_rdma_get_lkey(device, iov, &lkey))) {
1474 		/* This is a very rare case that can occur when using DPDK version < 19.05 */
1475 		SPDK_ERRLOG("Data buffer split over multiple RDMA Memory Regions. Removing it from circulation.\n");
1476 		return false;
1477 	}
1478 
1479 	if (spdk_likely(!dif_ctx)) {
1480 		sg_ele->lkey = lkey;
1481 		sg_ele->addr = (uintptr_t)(iov->iov_base);
1482 		sg_ele->length = iov->iov_len;
1483 		wr->num_sge++;
1484 	} else {
1485 		remaining = iov->iov_len - *_offset;
1486 		data_block_size = dif_ctx->block_size - dif_ctx->md_size;
1487 		md_size = dif_ctx->md_size;
1488 
1489 		while (remaining) {
1490 			if (wr->num_sge >= SPDK_NVMF_MAX_SGL_ENTRIES) {
1491 				if (*_num_extra_wrs > 0 && wr->next) {
1492 					*_wr = wr->next;
1493 					wr = *_wr;
1494 					wr->num_sge = 0;
1495 					sg_ele = &wr->sg_list[wr->num_sge];
1496 					(*_num_extra_wrs)--;
1497 				} else {
1498 					break;
1499 				}
1500 			}
1501 			sg_ele->lkey = lkey;
1502 			sg_ele->addr = (uintptr_t)((char *)iov->iov_base + *_offset);
1503 			sge_len = spdk_min(remaining, *_remaining_data_block);
1504 			sg_ele->length = sge_len;
1505 			remaining -= sge_len;
1506 			*_remaining_data_block -= sge_len;
1507 			*_offset += sge_len;
1508 
1509 			sg_ele++;
1510 			wr->num_sge++;
1511 
1512 			if (*_remaining_data_block == 0) {
1513 				/* skip metadata */
1514 				*_offset += md_size;
1515 				/* Metadata that do not fit this IO buffer will be included in the next IO buffer */
1516 				remaining -= spdk_min(remaining, md_size);
1517 				*_remaining_data_block = data_block_size;
1518 			}
1519 
1520 			if (remaining == 0) {
1521 				/* By subtracting the size of the last IOV from the offset, we ensure that we skip
1522 				   the remaining metadata bits at the beginning of the next buffer */
1523 				*_offset -= iov->iov_len;
1524 			}
1525 		}
1526 	}
1527 
1528 	return true;
1529 }
1530 
1531 static int
1532 nvmf_rdma_fill_wr_sgl(struct spdk_nvmf_rdma_poll_group *rgroup,
1533 		      struct spdk_nvmf_rdma_device *device,
1534 		      struct spdk_nvmf_rdma_request *rdma_req,
1535 		      struct ibv_send_wr *wr,
1536 		      uint32_t length,
1537 		      uint32_t num_extra_wrs)
1538 {
1539 	struct spdk_nvmf_request *req = &rdma_req->req;
1540 	struct spdk_dif_ctx *dif_ctx = NULL;
1541 	uint32_t remaining_data_block = 0;
1542 	uint32_t offset = 0;
1543 
1544 	if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
1545 		dif_ctx = &rdma_req->req.dif.dif_ctx;
1546 		remaining_data_block = dif_ctx->block_size - dif_ctx->md_size;
1547 	}
1548 
1549 	wr->num_sge = 0;
1550 
1551 	while (length && (num_extra_wrs || wr->num_sge < SPDK_NVMF_MAX_SGL_ENTRIES)) {
1552 		while (spdk_unlikely(!nvmf_rdma_fill_wr_sge(device, &req->iov[rdma_req->iovpos], &wr,
1553 				     &remaining_data_block, &offset, &num_extra_wrs, dif_ctx))) {
1554 			if (nvmf_rdma_replace_buffer(rgroup, &req->buffers[rdma_req->iovpos]) == -ENOMEM) {
1555 				return -ENOMEM;
1556 			}
1557 			req->iov[rdma_req->iovpos].iov_base = (void *)((uintptr_t)(req->buffers[rdma_req->iovpos] +
1558 							      NVMF_DATA_BUFFER_MASK) &
1559 							      ~NVMF_DATA_BUFFER_MASK);
1560 		}
1561 
1562 		length -= req->iov[rdma_req->iovpos].iov_len;
1563 		rdma_req->iovpos++;
1564 	}
1565 
1566 	if (length) {
1567 		SPDK_ERRLOG("Not enough SG entries to hold data buffer\n");
1568 		return -EINVAL;
1569 	}
1570 
1571 	return 0;
1572 }
1573 
1574 static inline uint32_t
1575 nvmf_rdma_calc_num_wrs(uint32_t length, uint32_t io_unit_size, uint32_t block_size)
1576 {
1577 	/* estimate the number of SG entries and WRs needed to process the request */
1578 	uint32_t num_sge = 0;
1579 	uint32_t i;
1580 	uint32_t num_buffers = SPDK_CEIL_DIV(length, io_unit_size);
1581 
1582 	for (i = 0; i < num_buffers && length > 0; i++) {
1583 		uint32_t buffer_len = spdk_min(length, io_unit_size);
1584 		uint32_t num_sge_in_block = SPDK_CEIL_DIV(buffer_len, block_size);
1585 
1586 		if (num_sge_in_block * block_size > buffer_len) {
1587 			++num_sge_in_block;
1588 		}
1589 		num_sge += num_sge_in_block;
1590 		length -= buffer_len;
1591 	}
1592 	return SPDK_CEIL_DIV(num_sge, SPDK_NVMF_MAX_SGL_ENTRIES);
1593 }
1594 
1595 static int
1596 nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1597 			    struct spdk_nvmf_rdma_device *device,
1598 			    struct spdk_nvmf_rdma_request *rdma_req,
1599 			    uint32_t length)
1600 {
1601 	struct spdk_nvmf_rdma_qpair		*rqpair;
1602 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1603 	struct spdk_nvmf_request		*req = &rdma_req->req;
1604 	struct ibv_send_wr			*wr = &rdma_req->data.wr;
1605 	int					rc;
1606 	uint32_t				num_wrs = 1;
1607 
1608 	rqpair = SPDK_CONTAINEROF(req->qpair, struct spdk_nvmf_rdma_qpair, qpair);
1609 	rgroup = rqpair->poller->group;
1610 
1611 	/* rdma wr specifics */
1612 	nvmf_rdma_setup_request(rdma_req);
1613 
1614 	rc = spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport,
1615 					   length);
1616 	if (rc != 0) {
1617 		return rc;
1618 	}
1619 
1620 	assert(req->iovcnt <= rqpair->max_send_sge);
1621 
1622 	rdma_req->iovpos = 0;
1623 
1624 	if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1625 		num_wrs = nvmf_rdma_calc_num_wrs(length, rtransport->transport.opts.io_unit_size,
1626 						 req->dif.dif_ctx.block_size);
1627 		if (num_wrs > 1) {
1628 			rc = nvmf_request_alloc_wrs(rtransport, rdma_req, num_wrs - 1);
1629 			if (rc != 0) {
1630 				goto err_exit;
1631 			}
1632 		}
1633 	}
1634 
1635 	rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, wr, length, num_wrs - 1);
1636 	if (spdk_unlikely(rc != 0)) {
1637 		goto err_exit;
1638 	}
1639 
1640 	if (spdk_unlikely(num_wrs > 1)) {
1641 		nvmf_rdma_update_remote_addr(rdma_req, num_wrs);
1642 	}
1643 
1644 	/* set the number of outstanding data WRs for this request. */
1645 	rdma_req->num_outstanding_data_wr = num_wrs;
1646 
1647 	return rc;
1648 
1649 err_exit:
1650 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1651 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1652 	req->iovcnt = 0;
1653 	return rc;
1654 }
1655 
1656 static int
1657 nvmf_rdma_request_fill_iovs_multi_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1658 				      struct spdk_nvmf_rdma_device *device,
1659 				      struct spdk_nvmf_rdma_request *rdma_req)
1660 {
1661 	struct spdk_nvmf_rdma_qpair		*rqpair;
1662 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1663 	struct ibv_send_wr			*current_wr;
1664 	struct spdk_nvmf_request		*req = &rdma_req->req;
1665 	struct spdk_nvme_sgl_descriptor		*inline_segment, *desc;
1666 	uint32_t				num_sgl_descriptors;
1667 	uint32_t				lengths[SPDK_NVMF_MAX_SGL_ENTRIES];
1668 	uint32_t				i;
1669 	int					rc;
1670 
1671 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1672 	rgroup = rqpair->poller->group;
1673 
1674 	inline_segment = &req->cmd->nvme_cmd.dptr.sgl1;
1675 	assert(inline_segment->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT);
1676 	assert(inline_segment->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET);
1677 
1678 	num_sgl_descriptors = inline_segment->unkeyed.length / sizeof(struct spdk_nvme_sgl_descriptor);
1679 	assert(num_sgl_descriptors <= SPDK_NVMF_MAX_SGL_ENTRIES);
1680 
1681 	if (nvmf_request_alloc_wrs(rtransport, rdma_req, num_sgl_descriptors - 1) != 0) {
1682 		return -ENOMEM;
1683 	}
1684 
1685 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1686 	for (i = 0; i < num_sgl_descriptors; i++) {
1687 		if (spdk_likely(!req->dif.dif_insert_or_strip)) {
1688 			lengths[i] = desc->keyed.length;
1689 		} else {
1690 			req->dif.orig_length += desc->keyed.length;
1691 			lengths[i] = spdk_dif_get_length_with_md(desc->keyed.length, &req->dif.dif_ctx);
1692 			req->dif.elba_length += lengths[i];
1693 		}
1694 		desc++;
1695 	}
1696 
1697 	rc = spdk_nvmf_request_get_buffers_multi(req, &rgroup->group, &rtransport->transport,
1698 			lengths, num_sgl_descriptors);
1699 	if (rc != 0) {
1700 		nvmf_rdma_request_free_data(rdma_req, rtransport);
1701 		return rc;
1702 	}
1703 
1704 	/* The first WR must always be the embedded data WR. This is how we unwind them later. */
1705 	current_wr = &rdma_req->data.wr;
1706 	assert(current_wr != NULL);
1707 
1708 	req->length = 0;
1709 	rdma_req->iovpos = 0;
1710 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1711 	for (i = 0; i < num_sgl_descriptors; i++) {
1712 		/* The descriptors must be keyed data block descriptors with an address, not an offset. */
1713 		if (spdk_unlikely(desc->generic.type != SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK ||
1714 				  desc->keyed.subtype != SPDK_NVME_SGL_SUBTYPE_ADDRESS)) {
1715 			rc = -EINVAL;
1716 			goto err_exit;
1717 		}
1718 
1719 		current_wr->num_sge = 0;
1720 
1721 		rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, current_wr, lengths[i], 0);
1722 		if (rc != 0) {
1723 			rc = -ENOMEM;
1724 			goto err_exit;
1725 		}
1726 
1727 		req->length += desc->keyed.length;
1728 		current_wr->wr.rdma.rkey = desc->keyed.key;
1729 		current_wr->wr.rdma.remote_addr = desc->address;
1730 		current_wr = current_wr->next;
1731 		desc++;
1732 	}
1733 
1734 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1735 	/* Go back to the last descriptor in the list. */
1736 	desc--;
1737 	if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1738 		if (desc->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1739 			rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1740 			rdma_req->rsp.wr.imm_data = desc->keyed.key;
1741 		}
1742 	}
1743 #endif
1744 
1745 	rdma_req->num_outstanding_data_wr = num_sgl_descriptors;
1746 
1747 	return 0;
1748 
1749 err_exit:
1750 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1751 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1752 	return rc;
1753 }
1754 
1755 static int
1756 nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1757 			    struct spdk_nvmf_rdma_device *device,
1758 			    struct spdk_nvmf_rdma_request *rdma_req)
1759 {
1760 	struct spdk_nvmf_request		*req = &rdma_req->req;
1761 	struct spdk_nvme_cpl			*rsp;
1762 	struct spdk_nvme_sgl_descriptor		*sgl;
1763 	int					rc;
1764 	uint32_t				length;
1765 
1766 	rsp = &req->rsp->nvme_cpl;
1767 	sgl = &req->cmd->nvme_cmd.dptr.sgl1;
1768 
1769 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1770 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1771 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1772 
1773 		length = sgl->keyed.length;
1774 		if (length > rtransport->transport.opts.max_io_size) {
1775 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1776 				    length, rtransport->transport.opts.max_io_size);
1777 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1778 			return -1;
1779 		}
1780 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1781 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1782 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1783 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1784 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1785 			}
1786 		}
1787 #endif
1788 
1789 		/* fill request length and populate iovs */
1790 		req->length = length;
1791 
1792 		if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1793 			req->dif.orig_length = length;
1794 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
1795 			req->dif.elba_length = length;
1796 		}
1797 
1798 		rc = nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req, length);
1799 		if (spdk_unlikely(rc < 0)) {
1800 			if (rc == -EINVAL) {
1801 				SPDK_ERRLOG("SGL length exceeds the max I/O size\n");
1802 				rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1803 				return -1;
1804 			}
1805 			/* No available buffers. Queue this request up. */
1806 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1807 			return 0;
1808 		}
1809 
1810 		/* backward compatible */
1811 		req->data = req->iov[0].iov_base;
1812 
1813 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1814 			      req->iovcnt);
1815 
1816 		return 0;
1817 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1818 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1819 		uint64_t offset = sgl->address;
1820 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1821 
1822 		SPDK_DEBUGLOG(SPDK_LOG_NVMF, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1823 			      offset, sgl->unkeyed.length);
1824 
1825 		if (offset > max_len) {
1826 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1827 				    offset, max_len);
1828 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1829 			return -1;
1830 		}
1831 		max_len -= (uint32_t)offset;
1832 
1833 		if (sgl->unkeyed.length > max_len) {
1834 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1835 				    sgl->unkeyed.length, max_len);
1836 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1837 			return -1;
1838 		}
1839 
1840 		rdma_req->num_outstanding_data_wr = 0;
1841 		req->data = rdma_req->recv->buf + offset;
1842 		req->data_from_pool = false;
1843 		req->length = sgl->unkeyed.length;
1844 
1845 		req->iov[0].iov_base = req->data;
1846 		req->iov[0].iov_len = req->length;
1847 		req->iovcnt = 1;
1848 
1849 		return 0;
1850 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT &&
1851 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1852 
1853 		rc = nvmf_rdma_request_fill_iovs_multi_sgl(rtransport, device, rdma_req);
1854 		if (rc == -ENOMEM) {
1855 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1856 			return 0;
1857 		} else if (rc == -EINVAL) {
1858 			SPDK_ERRLOG("Multi SGL element request length exceeds the max I/O size\n");
1859 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1860 			return -1;
1861 		}
1862 
1863 		/* backward compatible */
1864 		req->data = req->iov[0].iov_base;
1865 
1866 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1867 			      req->iovcnt);
1868 
1869 		return 0;
1870 	}
1871 
1872 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1873 		    sgl->generic.type, sgl->generic.subtype);
1874 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1875 	return -1;
1876 }
1877 
1878 static void
1879 _nvmf_rdma_request_free(struct spdk_nvmf_rdma_request *rdma_req,
1880 			struct spdk_nvmf_rdma_transport	*rtransport)
1881 {
1882 	struct spdk_nvmf_rdma_qpair		*rqpair;
1883 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1884 
1885 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1886 	if (rdma_req->req.data_from_pool) {
1887 		rgroup = rqpair->poller->group;
1888 
1889 		spdk_nvmf_request_free_buffers(&rdma_req->req, &rgroup->group, &rtransport->transport);
1890 	}
1891 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1892 	rdma_req->req.length = 0;
1893 	rdma_req->req.iovcnt = 0;
1894 	rdma_req->req.data = NULL;
1895 	rdma_req->rsp.wr.next = NULL;
1896 	rdma_req->data.wr.next = NULL;
1897 	memset(&rdma_req->req.dif, 0, sizeof(rdma_req->req.dif));
1898 	rqpair->qd--;
1899 
1900 	STAILQ_INSERT_HEAD(&rqpair->resources->free_queue, rdma_req, state_link);
1901 	rdma_req->state = RDMA_REQUEST_STATE_FREE;
1902 }
1903 
1904 bool
1905 nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
1906 			  struct spdk_nvmf_rdma_request *rdma_req)
1907 {
1908 	struct spdk_nvmf_rdma_qpair	*rqpair;
1909 	struct spdk_nvmf_rdma_device	*device;
1910 	struct spdk_nvmf_rdma_poll_group *rgroup;
1911 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
1912 	int				rc;
1913 	struct spdk_nvmf_rdma_recv	*rdma_recv;
1914 	enum spdk_nvmf_rdma_request_state prev_state;
1915 	bool				progress = false;
1916 	int				data_posted;
1917 	uint32_t			num_blocks;
1918 
1919 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1920 	device = rqpair->device;
1921 	rgroup = rqpair->poller->group;
1922 
1923 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
1924 
1925 	/* If the queue pair is in an error state, force the request to the completed state
1926 	 * to release resources. */
1927 	if (rqpair->ibv_state == IBV_QPS_ERR || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1928 		if (rdma_req->state == RDMA_REQUEST_STATE_NEED_BUFFER) {
1929 			STAILQ_REMOVE(&rgroup->group.pending_buf_queue, &rdma_req->req, spdk_nvmf_request, buf_link);
1930 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING) {
1931 			STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1932 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING) {
1933 			STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1934 		}
1935 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1936 	}
1937 
1938 	/* The loop here is to allow for several back-to-back state changes. */
1939 	do {
1940 		prev_state = rdma_req->state;
1941 
1942 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p entering state %d\n", rdma_req, prev_state);
1943 
1944 		switch (rdma_req->state) {
1945 		case RDMA_REQUEST_STATE_FREE:
1946 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
1947 			 * to escape this state. */
1948 			break;
1949 		case RDMA_REQUEST_STATE_NEW:
1950 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
1951 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1952 			rdma_recv = rdma_req->recv;
1953 
1954 			/* The first element of the SGL is the NVMe command */
1955 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
1956 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
1957 
1958 			if (rqpair->ibv_state == IBV_QPS_ERR  || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1959 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1960 				break;
1961 			}
1962 
1963 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&rdma_req->req, &rdma_req->req.dif.dif_ctx))) {
1964 				rdma_req->req.dif.dif_insert_or_strip = true;
1965 			}
1966 
1967 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1968 			rdma_req->rsp.wr.opcode = IBV_WR_SEND;
1969 			rdma_req->rsp.wr.imm_data = 0;
1970 #endif
1971 
1972 			/* The next state transition depends on the data transfer needs of this request. */
1973 			rdma_req->req.xfer = spdk_nvmf_req_get_xfer(&rdma_req->req);
1974 
1975 			if (spdk_unlikely(rdma_req->req.xfer == SPDK_NVME_DATA_BIDIRECTIONAL)) {
1976 				rsp->status.sct = SPDK_NVME_SCT_GENERIC;
1977 				rsp->status.sc = SPDK_NVME_SC_INVALID_OPCODE;
1978 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1979 				SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p: invalid xfer type (BIDIRECTIONAL)\n", rdma_req);
1980 				break;
1981 			}
1982 
1983 			/* If no data to transfer, ready to execute. */
1984 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
1985 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1986 				break;
1987 			}
1988 
1989 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
1990 			STAILQ_INSERT_TAIL(&rgroup->group.pending_buf_queue, &rdma_req->req, buf_link);
1991 			break;
1992 		case RDMA_REQUEST_STATE_NEED_BUFFER:
1993 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
1994 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1995 
1996 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
1997 
1998 			if (&rdma_req->req != STAILQ_FIRST(&rgroup->group.pending_buf_queue)) {
1999 				/* This request needs to wait in line to obtain a buffer */
2000 				break;
2001 			}
2002 
2003 			/* Try to get a data buffer */
2004 			rc = nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
2005 			if (rc < 0) {
2006 				STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2007 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2008 				break;
2009 			}
2010 
2011 			if (!rdma_req->req.data) {
2012 				/* No buffers available. */
2013 				rgroup->stat.pending_data_buffer++;
2014 				break;
2015 			}
2016 
2017 			STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2018 
2019 			/* If data is transferring from host to controller and the data didn't
2020 			 * arrive using in capsule data, we need to do a transfer from the host.
2021 			 */
2022 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER &&
2023 			    rdma_req->req.data_from_pool) {
2024 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
2025 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
2026 				break;
2027 			}
2028 
2029 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
2030 			break;
2031 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
2032 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING, 0, 0,
2033 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2034 
2035 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_read_queue)) {
2036 				/* This request needs to wait in line to perform RDMA */
2037 				break;
2038 			}
2039 			if (rqpair->current_send_depth + rdma_req->num_outstanding_data_wr > rqpair->max_send_depth
2040 			    || rqpair->current_read_depth + rdma_req->num_outstanding_data_wr > rqpair->max_read_depth) {
2041 				/* We can only have so many WRs outstanding. we have to wait until some finish. */
2042 				rqpair->poller->stat.pending_rdma_read++;
2043 				break;
2044 			}
2045 
2046 			/* We have already verified that this request is the head of the queue. */
2047 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_read_queue, state_link);
2048 
2049 			rc = request_transfer_in(&rdma_req->req);
2050 			if (!rc) {
2051 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
2052 			} else {
2053 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
2054 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2055 			}
2056 			break;
2057 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2058 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2059 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2060 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
2061 			 * to escape this state. */
2062 			break;
2063 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
2064 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
2065 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2066 
2067 			if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
2068 				if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2069 					/* generate DIF for write operation */
2070 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2071 					assert(num_blocks > 0);
2072 
2073 					rc = spdk_dif_generate(rdma_req->req.iov, rdma_req->req.iovcnt,
2074 							       num_blocks, &rdma_req->req.dif.dif_ctx);
2075 					if (rc != 0) {
2076 						SPDK_ERRLOG("DIF generation failed\n");
2077 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2078 						spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2079 						break;
2080 					}
2081 				}
2082 
2083 				assert(rdma_req->req.dif.elba_length >= rdma_req->req.length);
2084 				/* set extended length before IO operation */
2085 				rdma_req->req.length = rdma_req->req.dif.elba_length;
2086 			}
2087 
2088 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
2089 			spdk_nvmf_request_exec(&rdma_req->req);
2090 			break;
2091 		case RDMA_REQUEST_STATE_EXECUTING:
2092 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
2093 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2094 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
2095 			 * to escape this state. */
2096 			break;
2097 		case RDMA_REQUEST_STATE_EXECUTED:
2098 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
2099 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2100 			if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
2101 			    rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2102 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_write_queue, rdma_req, state_link);
2103 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING;
2104 			} else {
2105 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2106 			}
2107 			if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
2108 				/* restore the original length */
2109 				rdma_req->req.length = rdma_req->req.dif.orig_length;
2110 
2111 				if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2112 					struct spdk_dif_error error_blk;
2113 
2114 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2115 
2116 					rc = spdk_dif_verify(rdma_req->req.iov, rdma_req->req.iovcnt, num_blocks,
2117 							     &rdma_req->req.dif.dif_ctx, &error_blk);
2118 					if (rc) {
2119 						struct spdk_nvme_cpl *rsp = &rdma_req->req.rsp->nvme_cpl;
2120 
2121 						SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n", error_blk.err_type,
2122 							    error_blk.err_offset);
2123 						rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2124 						rsp->status.sc = nvmf_rdma_dif_error_to_compl_status(error_blk.err_type);
2125 						rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2126 						STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2127 					}
2128 				}
2129 			}
2130 			break;
2131 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
2132 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING, 0, 0,
2133 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2134 
2135 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_write_queue)) {
2136 				/* This request needs to wait in line to perform RDMA */
2137 				break;
2138 			}
2139 			if ((rqpair->current_send_depth + rdma_req->num_outstanding_data_wr + 1) >
2140 			    rqpair->max_send_depth) {
2141 				/* We can only have so many WRs outstanding. we have to wait until some finish.
2142 				 * +1 since each request has an additional wr in the resp. */
2143 				rqpair->poller->stat.pending_rdma_write++;
2144 				break;
2145 			}
2146 
2147 			/* We have already verified that this request is the head of the queue. */
2148 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_write_queue, state_link);
2149 
2150 			/* The data transfer will be kicked off from
2151 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
2152 			 */
2153 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2154 			break;
2155 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
2156 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
2157 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2158 			rc = request_transfer_out(&rdma_req->req, &data_posted);
2159 			assert(rc == 0); /* No good way to handle this currently */
2160 			if (rc) {
2161 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2162 			} else {
2163 				rdma_req->state = data_posted ? RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
2164 						  RDMA_REQUEST_STATE_COMPLETING;
2165 			}
2166 			break;
2167 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2168 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2169 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2170 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2171 			 * to escape this state. */
2172 			break;
2173 		case RDMA_REQUEST_STATE_COMPLETING:
2174 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
2175 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2176 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2177 			 * to escape this state. */
2178 			break;
2179 		case RDMA_REQUEST_STATE_COMPLETED:
2180 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
2181 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2182 
2183 			rqpair->poller->stat.request_latency += spdk_get_ticks() - rdma_req->receive_tsc;
2184 			_nvmf_rdma_request_free(rdma_req, rtransport);
2185 			break;
2186 		case RDMA_REQUEST_NUM_STATES:
2187 		default:
2188 			assert(0);
2189 			break;
2190 		}
2191 
2192 		if (rdma_req->state != prev_state) {
2193 			progress = true;
2194 		}
2195 	} while (rdma_req->state != prev_state);
2196 
2197 	return progress;
2198 }
2199 
2200 /* Public API callbacks begin here */
2201 
2202 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
2203 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
2204 #define SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH 4096
2205 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
2206 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2207 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
2208 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
2209 #define SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS 4095
2210 #define SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE 32
2211 #define SPDK_NVMF_RDMA_DEFAULT_NO_SRQ false
2212 #define SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP false
2213 #define SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG 100
2214 #define SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC 1
2215 
2216 static void
2217 nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
2218 {
2219 	opts->max_queue_depth =		SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
2220 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2221 	opts->in_capsule_data_size =	SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
2222 	opts->max_io_size =		SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
2223 	opts->io_unit_size =		SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE;
2224 	opts->max_aq_depth =		SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
2225 	opts->num_shared_buffers =	SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS;
2226 	opts->buf_cache_size =		SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE;
2227 	opts->max_srq_depth =		SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH;
2228 	opts->no_srq =			SPDK_NVMF_RDMA_DEFAULT_NO_SRQ;
2229 	opts->dif_insert_or_strip =	SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP;
2230 	opts->acceptor_backlog =	SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2231 	opts->abort_timeout_sec =	SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC;
2232 }
2233 
2234 const struct spdk_mem_map_ops g_nvmf_rdma_map_ops = {
2235 	.notify_cb = nvmf_rdma_mem_notify,
2236 	.are_contiguous = nvmf_rdma_check_contiguous_entries
2237 };
2238 
2239 static int nvmf_rdma_destroy(struct spdk_nvmf_transport *transport);
2240 
2241 static struct spdk_nvmf_transport *
2242 nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
2243 {
2244 	int rc;
2245 	struct spdk_nvmf_rdma_transport *rtransport;
2246 	struct spdk_nvmf_rdma_device	*device, *tmp;
2247 	struct ibv_context		**contexts;
2248 	uint32_t			i;
2249 	int				flag;
2250 	uint32_t			sge_count;
2251 	uint32_t			min_shared_buffers;
2252 	int				max_device_sge = SPDK_NVMF_MAX_SGL_ENTRIES;
2253 	pthread_mutexattr_t		attr;
2254 
2255 	rtransport = calloc(1, sizeof(*rtransport));
2256 	if (!rtransport) {
2257 		return NULL;
2258 	}
2259 
2260 	if (pthread_mutexattr_init(&attr)) {
2261 		SPDK_ERRLOG("pthread_mutexattr_init() failed\n");
2262 		free(rtransport);
2263 		return NULL;
2264 	}
2265 
2266 	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) {
2267 		SPDK_ERRLOG("pthread_mutexattr_settype() failed\n");
2268 		pthread_mutexattr_destroy(&attr);
2269 		free(rtransport);
2270 		return NULL;
2271 	}
2272 
2273 	if (pthread_mutex_init(&rtransport->lock, &attr)) {
2274 		SPDK_ERRLOG("pthread_mutex_init() failed\n");
2275 		pthread_mutexattr_destroy(&attr);
2276 		free(rtransport);
2277 		return NULL;
2278 	}
2279 
2280 	pthread_mutexattr_destroy(&attr);
2281 
2282 	TAILQ_INIT(&rtransport->devices);
2283 	TAILQ_INIT(&rtransport->ports);
2284 	TAILQ_INIT(&rtransport->poll_groups);
2285 
2286 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
2287 
2288 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** RDMA Transport Init ***\n"
2289 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
2290 		     "  max_io_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
2291 		     "  in_capsule_data_size=%d, max_aq_depth=%d,\n"
2292 		     "  num_shared_buffers=%d, max_srq_depth=%d, no_srq=%d,"
2293 		     "  acceptor_backlog=%d, abort_timeout_sec=%d\n",
2294 		     opts->max_queue_depth,
2295 		     opts->max_io_size,
2296 		     opts->max_qpairs_per_ctrlr - 1,
2297 		     opts->io_unit_size,
2298 		     opts->in_capsule_data_size,
2299 		     opts->max_aq_depth,
2300 		     opts->num_shared_buffers,
2301 		     opts->max_srq_depth,
2302 		     opts->no_srq,
2303 		     opts->acceptor_backlog,
2304 		     opts->abort_timeout_sec);
2305 
2306 	/* I/O unit size cannot be larger than max I/O size */
2307 	if (opts->io_unit_size > opts->max_io_size) {
2308 		opts->io_unit_size = opts->max_io_size;
2309 	}
2310 
2311 	if (opts->acceptor_backlog <= 0) {
2312 		SPDK_ERRLOG("The acceptor backlog cannot be less than 1, setting to the default value of (%d).\n",
2313 			    SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG);
2314 		opts->acceptor_backlog = SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2315 	}
2316 
2317 	if (opts->num_shared_buffers < (SPDK_NVMF_MAX_SGL_ENTRIES * 2)) {
2318 		SPDK_ERRLOG("The number of shared data buffers (%d) is less than"
2319 			    "the minimum number required to guarantee that forward progress can be made (%d)\n",
2320 			    opts->num_shared_buffers, (SPDK_NVMF_MAX_SGL_ENTRIES * 2));
2321 		nvmf_rdma_destroy(&rtransport->transport);
2322 		return NULL;
2323 	}
2324 
2325 	min_shared_buffers = spdk_thread_get_count() * opts->buf_cache_size;
2326 	if (min_shared_buffers > opts->num_shared_buffers) {
2327 		SPDK_ERRLOG("There are not enough buffers to satisfy"
2328 			    "per-poll group caches for each thread. (%" PRIu32 ")"
2329 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
2330 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
2331 		nvmf_rdma_destroy(&rtransport->transport);
2332 		return NULL;
2333 	}
2334 
2335 	sge_count = opts->max_io_size / opts->io_unit_size;
2336 	if (sge_count > NVMF_DEFAULT_TX_SGE) {
2337 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
2338 		nvmf_rdma_destroy(&rtransport->transport);
2339 		return NULL;
2340 	}
2341 
2342 	rtransport->event_channel = rdma_create_event_channel();
2343 	if (rtransport->event_channel == NULL) {
2344 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
2345 		nvmf_rdma_destroy(&rtransport->transport);
2346 		return NULL;
2347 	}
2348 
2349 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
2350 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2351 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
2352 			    rtransport->event_channel->fd, spdk_strerror(errno));
2353 		nvmf_rdma_destroy(&rtransport->transport);
2354 		return NULL;
2355 	}
2356 
2357 	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data",
2358 				   opts->max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES,
2359 				   sizeof(struct spdk_nvmf_rdma_request_data),
2360 				   SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
2361 				   SPDK_ENV_SOCKET_ID_ANY);
2362 	if (!rtransport->data_wr_pool) {
2363 		SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");
2364 		nvmf_rdma_destroy(&rtransport->transport);
2365 		return NULL;
2366 	}
2367 
2368 	contexts = rdma_get_devices(NULL);
2369 	if (contexts == NULL) {
2370 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2371 		nvmf_rdma_destroy(&rtransport->transport);
2372 		return NULL;
2373 	}
2374 
2375 	i = 0;
2376 	rc = 0;
2377 	while (contexts[i] != NULL) {
2378 		device = calloc(1, sizeof(*device));
2379 		if (!device) {
2380 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
2381 			rc = -ENOMEM;
2382 			break;
2383 		}
2384 		device->context = contexts[i];
2385 		rc = ibv_query_device(device->context, &device->attr);
2386 		if (rc < 0) {
2387 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2388 			free(device);
2389 			break;
2390 
2391 		}
2392 
2393 		max_device_sge = spdk_min(max_device_sge, device->attr.max_sge);
2394 
2395 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2396 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
2397 			SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
2398 			SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
2399 		}
2400 
2401 		/**
2402 		 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
2403 		 * The Soft-RoCE RXE driver does not currently support send with invalidate,
2404 		 * but incorrectly reports that it does. There are changes making their way
2405 		 * through the kernel now that will enable this feature. When they are merged,
2406 		 * we can conditionally enable this feature.
2407 		 *
2408 		 * TODO: enable this for versions of the kernel rxe driver that support it.
2409 		 */
2410 		if (device->attr.vendor_id == 0) {
2411 			device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
2412 		}
2413 #endif
2414 
2415 		/* set up device context async ev fd as NON_BLOCKING */
2416 		flag = fcntl(device->context->async_fd, F_GETFL);
2417 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
2418 		if (rc < 0) {
2419 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
2420 			free(device);
2421 			break;
2422 		}
2423 
2424 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
2425 		i++;
2426 
2427 		if (g_nvmf_hooks.get_ibv_pd) {
2428 			device->pd = g_nvmf_hooks.get_ibv_pd(NULL, device->context);
2429 		} else {
2430 			device->pd = ibv_alloc_pd(device->context);
2431 		}
2432 
2433 		if (!device->pd) {
2434 			SPDK_ERRLOG("Unable to allocate protection domain.\n");
2435 			rc = -ENOMEM;
2436 			break;
2437 		}
2438 
2439 		assert(device->map == NULL);
2440 
2441 		device->map = spdk_mem_map_alloc(0, &g_nvmf_rdma_map_ops, device->pd);
2442 		if (!device->map) {
2443 			SPDK_ERRLOG("Unable to allocate memory map for listen address\n");
2444 			rc = -ENOMEM;
2445 			break;
2446 		}
2447 
2448 		assert(device->map != NULL);
2449 		assert(device->pd != NULL);
2450 	}
2451 	rdma_free_devices(contexts);
2452 
2453 	if (opts->io_unit_size * max_device_sge < opts->max_io_size) {
2454 		/* divide and round up. */
2455 		opts->io_unit_size = (opts->max_io_size + max_device_sge - 1) / max_device_sge;
2456 
2457 		/* round up to the nearest 4k. */
2458 		opts->io_unit_size = (opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT - 1) & ~NVMF_DATA_BUFFER_MASK;
2459 
2460 		opts->io_unit_size = spdk_max(opts->io_unit_size, SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
2461 		SPDK_NOTICELOG("Adjusting the io unit size to fit the device's maximum I/O size. New I/O unit size %u\n",
2462 			       opts->io_unit_size);
2463 	}
2464 
2465 	if (rc < 0) {
2466 		nvmf_rdma_destroy(&rtransport->transport);
2467 		return NULL;
2468 	}
2469 
2470 	/* Set up poll descriptor array to monitor events from RDMA and IB
2471 	 * in a single poll syscall
2472 	 */
2473 	rtransport->npoll_fds = i + 1;
2474 	i = 0;
2475 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
2476 	if (rtransport->poll_fds == NULL) {
2477 		SPDK_ERRLOG("poll_fds allocation failed\n");
2478 		nvmf_rdma_destroy(&rtransport->transport);
2479 		return NULL;
2480 	}
2481 
2482 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
2483 	rtransport->poll_fds[i++].events = POLLIN;
2484 
2485 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2486 		rtransport->poll_fds[i].fd = device->context->async_fd;
2487 		rtransport->poll_fds[i++].events = POLLIN;
2488 	}
2489 
2490 	return &rtransport->transport;
2491 }
2492 
2493 static int
2494 nvmf_rdma_destroy(struct spdk_nvmf_transport *transport)
2495 {
2496 	struct spdk_nvmf_rdma_transport	*rtransport;
2497 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
2498 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
2499 
2500 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2501 
2502 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
2503 		TAILQ_REMOVE(&rtransport->ports, port, link);
2504 		rdma_destroy_id(port->id);
2505 		free(port);
2506 	}
2507 
2508 	if (rtransport->poll_fds != NULL) {
2509 		free(rtransport->poll_fds);
2510 	}
2511 
2512 	if (rtransport->event_channel != NULL) {
2513 		rdma_destroy_event_channel(rtransport->event_channel);
2514 	}
2515 
2516 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
2517 		TAILQ_REMOVE(&rtransport->devices, device, link);
2518 		if (device->map) {
2519 			spdk_mem_map_free(&device->map);
2520 		}
2521 		if (device->pd) {
2522 			if (!g_nvmf_hooks.get_ibv_pd) {
2523 				ibv_dealloc_pd(device->pd);
2524 			}
2525 		}
2526 		free(device);
2527 	}
2528 
2529 	if (rtransport->data_wr_pool != NULL) {
2530 		if (spdk_mempool_count(rtransport->data_wr_pool) !=
2531 		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {
2532 			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",
2533 				    spdk_mempool_count(rtransport->data_wr_pool),
2534 				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);
2535 		}
2536 	}
2537 
2538 	spdk_mempool_free(rtransport->data_wr_pool);
2539 
2540 	pthread_mutex_destroy(&rtransport->lock);
2541 	free(rtransport);
2542 
2543 	return 0;
2544 }
2545 
2546 static int
2547 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2548 			  struct spdk_nvme_transport_id *trid,
2549 			  bool peer);
2550 
2551 static int
2552 nvmf_rdma_listen(struct spdk_nvmf_transport *transport,
2553 		 const struct spdk_nvme_transport_id *trid)
2554 {
2555 	struct spdk_nvmf_rdma_transport	*rtransport;
2556 	struct spdk_nvmf_rdma_device	*device;
2557 	struct spdk_nvmf_rdma_port	*port;
2558 	struct addrinfo			*res;
2559 	struct addrinfo			hints;
2560 	int				family;
2561 	int				rc;
2562 
2563 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2564 	assert(rtransport->event_channel != NULL);
2565 
2566 	pthread_mutex_lock(&rtransport->lock);
2567 	port = calloc(1, sizeof(*port));
2568 	if (!port) {
2569 		SPDK_ERRLOG("Port allocation failed\n");
2570 		pthread_mutex_unlock(&rtransport->lock);
2571 		return -ENOMEM;
2572 	}
2573 
2574 	port->trid = trid;
2575 
2576 	switch (trid->adrfam) {
2577 	case SPDK_NVMF_ADRFAM_IPV4:
2578 		family = AF_INET;
2579 		break;
2580 	case SPDK_NVMF_ADRFAM_IPV6:
2581 		family = AF_INET6;
2582 		break;
2583 	default:
2584 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", trid->adrfam);
2585 		free(port);
2586 		pthread_mutex_unlock(&rtransport->lock);
2587 		return -EINVAL;
2588 	}
2589 
2590 	memset(&hints, 0, sizeof(hints));
2591 	hints.ai_family = family;
2592 	hints.ai_flags = AI_NUMERICSERV;
2593 	hints.ai_socktype = SOCK_STREAM;
2594 	hints.ai_protocol = 0;
2595 
2596 	rc = getaddrinfo(trid->traddr, trid->trsvcid, &hints, &res);
2597 	if (rc) {
2598 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
2599 		free(port);
2600 		pthread_mutex_unlock(&rtransport->lock);
2601 		return -EINVAL;
2602 	}
2603 
2604 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
2605 	if (rc < 0) {
2606 		SPDK_ERRLOG("rdma_create_id() failed\n");
2607 		freeaddrinfo(res);
2608 		free(port);
2609 		pthread_mutex_unlock(&rtransport->lock);
2610 		return rc;
2611 	}
2612 
2613 	rc = rdma_bind_addr(port->id, res->ai_addr);
2614 	freeaddrinfo(res);
2615 
2616 	if (rc < 0) {
2617 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
2618 		rdma_destroy_id(port->id);
2619 		free(port);
2620 		pthread_mutex_unlock(&rtransport->lock);
2621 		return rc;
2622 	}
2623 
2624 	if (!port->id->verbs) {
2625 		SPDK_ERRLOG("ibv_context is null\n");
2626 		rdma_destroy_id(port->id);
2627 		free(port);
2628 		pthread_mutex_unlock(&rtransport->lock);
2629 		return -1;
2630 	}
2631 
2632 	rc = rdma_listen(port->id, transport->opts.acceptor_backlog);
2633 	if (rc < 0) {
2634 		SPDK_ERRLOG("rdma_listen() failed\n");
2635 		rdma_destroy_id(port->id);
2636 		free(port);
2637 		pthread_mutex_unlock(&rtransport->lock);
2638 		return rc;
2639 	}
2640 
2641 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2642 		if (device->context == port->id->verbs) {
2643 			port->device = device;
2644 			break;
2645 		}
2646 	}
2647 	if (!port->device) {
2648 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
2649 			    port->id->verbs);
2650 		rdma_destroy_id(port->id);
2651 		free(port);
2652 		pthread_mutex_unlock(&rtransport->lock);
2653 		return -EINVAL;
2654 	}
2655 
2656 	SPDK_NOTICELOG("*** NVMe/RDMA Target Listening on %s port %s ***\n",
2657 		       trid->traddr, trid->trsvcid);
2658 
2659 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
2660 	pthread_mutex_unlock(&rtransport->lock);
2661 	return 0;
2662 }
2663 
2664 static void
2665 nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
2666 		      const struct spdk_nvme_transport_id *trid)
2667 {
2668 	struct spdk_nvmf_rdma_transport *rtransport;
2669 	struct spdk_nvmf_rdma_port *port, *tmp;
2670 
2671 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2672 
2673 	pthread_mutex_lock(&rtransport->lock);
2674 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
2675 		if (spdk_nvme_transport_id_compare(port->trid, trid) == 0) {
2676 			TAILQ_REMOVE(&rtransport->ports, port, link);
2677 			rdma_destroy_id(port->id);
2678 			free(port);
2679 			break;
2680 		}
2681 	}
2682 
2683 	pthread_mutex_unlock(&rtransport->lock);
2684 }
2685 
2686 static void
2687 nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
2688 				struct spdk_nvmf_rdma_qpair *rqpair, bool drain)
2689 {
2690 	struct spdk_nvmf_request *req, *tmp;
2691 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
2692 	struct spdk_nvmf_rdma_resources *resources;
2693 
2694 	/* We process I/O in the data transfer pending queue at the highest priority. RDMA reads first */
2695 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_read_queue, state_link, req_tmp) {
2696 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2697 			break;
2698 		}
2699 	}
2700 
2701 	/* Then RDMA writes since reads have stronger restrictions than writes */
2702 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_write_queue, state_link, req_tmp) {
2703 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2704 			break;
2705 		}
2706 	}
2707 
2708 	/* The second highest priority is I/O waiting on memory buffers. */
2709 	STAILQ_FOREACH_SAFE(req, &rqpair->poller->group->group.pending_buf_queue, buf_link, tmp) {
2710 		rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
2711 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2712 			break;
2713 		}
2714 	}
2715 
2716 	resources = rqpair->resources;
2717 	while (!STAILQ_EMPTY(&resources->free_queue) && !STAILQ_EMPTY(&resources->incoming_queue)) {
2718 		rdma_req = STAILQ_FIRST(&resources->free_queue);
2719 		STAILQ_REMOVE_HEAD(&resources->free_queue, state_link);
2720 		rdma_req->recv = STAILQ_FIRST(&resources->incoming_queue);
2721 		STAILQ_REMOVE_HEAD(&resources->incoming_queue, link);
2722 
2723 		if (rqpair->srq != NULL) {
2724 			rdma_req->req.qpair = &rdma_req->recv->qpair->qpair;
2725 			rdma_req->recv->qpair->qd++;
2726 		} else {
2727 			rqpair->qd++;
2728 		}
2729 
2730 		rdma_req->receive_tsc = rdma_req->recv->receive_tsc;
2731 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
2732 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false) {
2733 			break;
2734 		}
2735 	}
2736 	if (!STAILQ_EMPTY(&resources->incoming_queue) && STAILQ_EMPTY(&resources->free_queue)) {
2737 		rqpair->poller->stat.pending_free_request++;
2738 	}
2739 }
2740 
2741 static void
2742 nvmf_rdma_destroy_drained_qpair(struct spdk_nvmf_rdma_qpair *rqpair)
2743 {
2744 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
2745 			struct spdk_nvmf_rdma_transport, transport);
2746 
2747 	nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
2748 
2749 	/* nvmr_rdma_close_qpair is not called */
2750 	if (!rqpair->to_close) {
2751 		return;
2752 	}
2753 
2754 	/* In non SRQ path, we will reach rqpair->max_queue_depth. In SRQ path, we will get the last_wqe event. */
2755 	if (rqpair->current_send_depth != 0) {
2756 		return;
2757 	}
2758 
2759 	if (rqpair->srq == NULL && rqpair->current_recv_depth != rqpair->max_queue_depth) {
2760 		return;
2761 	}
2762 
2763 	/* Judge whether the device is emulated by Software RoCE.
2764 	 * And it will not send last_wqe event
2765 	 */
2766 	if (rqpair->srq != NULL && rqpair->device->attr.vendor_id != 0 &&
2767 	    rqpair->last_wqe_reached == false) {
2768 		return;
2769 	}
2770 
2771 	assert(rqpair->qpair.state == SPDK_NVMF_QPAIR_ERROR);
2772 
2773 	nvmf_rdma_qpair_destroy(rqpair);
2774 }
2775 
2776 static int
2777 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
2778 {
2779 	struct spdk_nvmf_qpair		*qpair;
2780 	struct spdk_nvmf_rdma_qpair	*rqpair;
2781 
2782 	if (evt->id == NULL) {
2783 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
2784 		return -1;
2785 	}
2786 
2787 	qpair = evt->id->context;
2788 	if (qpair == NULL) {
2789 		SPDK_ERRLOG("disconnect request: no active connection\n");
2790 		return -1;
2791 	}
2792 
2793 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2794 
2795 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair->cm_id, 0);
2796 
2797 	spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2798 
2799 	return 0;
2800 }
2801 
2802 #ifdef DEBUG
2803 static const char *CM_EVENT_STR[] = {
2804 	"RDMA_CM_EVENT_ADDR_RESOLVED",
2805 	"RDMA_CM_EVENT_ADDR_ERROR",
2806 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
2807 	"RDMA_CM_EVENT_ROUTE_ERROR",
2808 	"RDMA_CM_EVENT_CONNECT_REQUEST",
2809 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
2810 	"RDMA_CM_EVENT_CONNECT_ERROR",
2811 	"RDMA_CM_EVENT_UNREACHABLE",
2812 	"RDMA_CM_EVENT_REJECTED",
2813 	"RDMA_CM_EVENT_ESTABLISHED",
2814 	"RDMA_CM_EVENT_DISCONNECTED",
2815 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
2816 	"RDMA_CM_EVENT_MULTICAST_JOIN",
2817 	"RDMA_CM_EVENT_MULTICAST_ERROR",
2818 	"RDMA_CM_EVENT_ADDR_CHANGE",
2819 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
2820 };
2821 #endif /* DEBUG */
2822 
2823 static void
2824 nvmf_rdma_disconnect_qpairs_on_port(struct spdk_nvmf_rdma_transport *rtransport,
2825 				    struct spdk_nvmf_rdma_port *port)
2826 {
2827 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2828 	struct spdk_nvmf_rdma_poller		*rpoller;
2829 	struct spdk_nvmf_rdma_qpair		*rqpair;
2830 
2831 	TAILQ_FOREACH(rgroup, &rtransport->poll_groups, link) {
2832 		TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
2833 			TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
2834 				if (rqpair->listen_id == port->id) {
2835 					spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2836 				}
2837 			}
2838 		}
2839 	}
2840 }
2841 
2842 static bool
2843 nvmf_rdma_handle_cm_event_addr_change(struct spdk_nvmf_transport *transport,
2844 				      struct rdma_cm_event *event)
2845 {
2846 	const struct spdk_nvme_transport_id	*trid;
2847 	struct spdk_nvmf_rdma_port		*port;
2848 	struct spdk_nvmf_rdma_transport		*rtransport;
2849 	bool					event_acked = false;
2850 
2851 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2852 	TAILQ_FOREACH(port, &rtransport->ports, link) {
2853 		if (port->id == event->id) {
2854 			SPDK_ERRLOG("ADDR_CHANGE: IP %s:%s migrated\n", port->trid->traddr, port->trid->trsvcid);
2855 			rdma_ack_cm_event(event);
2856 			event_acked = true;
2857 			trid = port->trid;
2858 			break;
2859 		}
2860 	}
2861 
2862 	if (event_acked) {
2863 		nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
2864 
2865 		nvmf_rdma_stop_listen(transport, trid);
2866 		nvmf_rdma_listen(transport, trid);
2867 	}
2868 
2869 	return event_acked;
2870 }
2871 
2872 static void
2873 nvmf_rdma_handle_cm_event_port_removal(struct spdk_nvmf_transport *transport,
2874 				       struct rdma_cm_event *event)
2875 {
2876 	struct spdk_nvmf_rdma_port		*port;
2877 	struct spdk_nvmf_rdma_transport		*rtransport;
2878 
2879 	port = event->id->context;
2880 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2881 
2882 	SPDK_NOTICELOG("Port %s:%s is being removed\n", port->trid->traddr, port->trid->trsvcid);
2883 
2884 	nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
2885 
2886 	rdma_ack_cm_event(event);
2887 
2888 	while (spdk_nvmf_transport_stop_listen(transport, port->trid) == 0) {
2889 		;
2890 	}
2891 }
2892 
2893 static void
2894 nvmf_process_cm_event(struct spdk_nvmf_transport *transport)
2895 {
2896 	struct spdk_nvmf_rdma_transport *rtransport;
2897 	struct rdma_cm_event		*event;
2898 	int				rc;
2899 	bool				event_acked;
2900 
2901 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2902 
2903 	if (rtransport->event_channel == NULL) {
2904 		return;
2905 	}
2906 
2907 	while (1) {
2908 		event_acked = false;
2909 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
2910 		if (rc) {
2911 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
2912 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
2913 			}
2914 			break;
2915 		}
2916 
2917 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
2918 
2919 		spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
2920 
2921 		switch (event->event) {
2922 		case RDMA_CM_EVENT_ADDR_RESOLVED:
2923 		case RDMA_CM_EVENT_ADDR_ERROR:
2924 		case RDMA_CM_EVENT_ROUTE_RESOLVED:
2925 		case RDMA_CM_EVENT_ROUTE_ERROR:
2926 			/* No action required. The target never attempts to resolve routes. */
2927 			break;
2928 		case RDMA_CM_EVENT_CONNECT_REQUEST:
2929 			rc = nvmf_rdma_connect(transport, event);
2930 			if (rc < 0) {
2931 				SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
2932 				break;
2933 			}
2934 			break;
2935 		case RDMA_CM_EVENT_CONNECT_RESPONSE:
2936 			/* The target never initiates a new connection. So this will not occur. */
2937 			break;
2938 		case RDMA_CM_EVENT_CONNECT_ERROR:
2939 			/* Can this happen? The docs say it can, but not sure what causes it. */
2940 			break;
2941 		case RDMA_CM_EVENT_UNREACHABLE:
2942 		case RDMA_CM_EVENT_REJECTED:
2943 			/* These only occur on the client side. */
2944 			break;
2945 		case RDMA_CM_EVENT_ESTABLISHED:
2946 			/* TODO: Should we be waiting for this event anywhere? */
2947 			break;
2948 		case RDMA_CM_EVENT_DISCONNECTED:
2949 			rc = nvmf_rdma_disconnect(event);
2950 			if (rc < 0) {
2951 				SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2952 				break;
2953 			}
2954 			break;
2955 		case RDMA_CM_EVENT_DEVICE_REMOVAL:
2956 			/* In case of device removal, kernel IB part triggers IBV_EVENT_DEVICE_FATAL
2957 			 * which triggers RDMA_CM_EVENT_DEVICE_REMOVAL on all cma_id’s.
2958 			 * Once these events are sent to SPDK, we should release all IB resources and
2959 			 * don't make attempts to call any ibv_query/modify/create functions. We can only call
2960 			 * ibv_destory* functions to release user space memory allocated by IB. All kernel
2961 			 * resources are already cleaned. */
2962 			if (event->id->qp) {
2963 				/* If rdma_cm event has a valid `qp` pointer then the event refers to the
2964 				 * corresponding qpair. Otherwise the event refers to a listening device */
2965 				rc = nvmf_rdma_disconnect(event);
2966 				if (rc < 0) {
2967 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2968 					break;
2969 				}
2970 			} else {
2971 				nvmf_rdma_handle_cm_event_port_removal(transport, event);
2972 				event_acked = true;
2973 			}
2974 			break;
2975 		case RDMA_CM_EVENT_MULTICAST_JOIN:
2976 		case RDMA_CM_EVENT_MULTICAST_ERROR:
2977 			/* Multicast is not used */
2978 			break;
2979 		case RDMA_CM_EVENT_ADDR_CHANGE:
2980 			event_acked = nvmf_rdma_handle_cm_event_addr_change(transport, event);
2981 			break;
2982 		case RDMA_CM_EVENT_TIMEWAIT_EXIT:
2983 			/* For now, do nothing. The target never re-uses queue pairs. */
2984 			break;
2985 		default:
2986 			SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
2987 			break;
2988 		}
2989 		if (!event_acked) {
2990 			rdma_ack_cm_event(event);
2991 		}
2992 	}
2993 }
2994 
2995 static void
2996 nvmf_rdma_handle_last_wqe_reached(struct spdk_nvmf_rdma_qpair *rqpair)
2997 {
2998 	rqpair->last_wqe_reached = true;
2999 	nvmf_rdma_destroy_drained_qpair(rqpair);
3000 }
3001 
3002 static void
3003 nvmf_rdma_qpair_process_ibv_event(void *ctx)
3004 {
3005 	struct spdk_nvmf_rdma_ibv_event_ctx *event_ctx = ctx;
3006 
3007 	if (event_ctx->rqpair) {
3008 		STAILQ_REMOVE(&event_ctx->rqpair->ibv_events, event_ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3009 		if (event_ctx->cb_fn) {
3010 			event_ctx->cb_fn(event_ctx->rqpair);
3011 		}
3012 	}
3013 	free(event_ctx);
3014 }
3015 
3016 static int
3017 nvmf_rdma_send_qpair_async_event(struct spdk_nvmf_rdma_qpair *rqpair,
3018 				 spdk_nvmf_rdma_qpair_ibv_event fn)
3019 {
3020 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx;
3021 	struct spdk_thread *thr = NULL;
3022 	int rc;
3023 
3024 	if (rqpair->qpair.group) {
3025 		thr = rqpair->qpair.group->thread;
3026 	} else if (rqpair->destruct_channel) {
3027 		thr = spdk_io_channel_get_thread(rqpair->destruct_channel);
3028 	}
3029 
3030 	if (!thr) {
3031 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "rqpair %p has no thread\n", rqpair);
3032 		return -EINVAL;
3033 	}
3034 
3035 	ctx = calloc(1, sizeof(*ctx));
3036 	if (!ctx) {
3037 		return -ENOMEM;
3038 	}
3039 
3040 	ctx->rqpair = rqpair;
3041 	ctx->cb_fn = fn;
3042 	STAILQ_INSERT_TAIL(&rqpair->ibv_events, ctx, link);
3043 
3044 	rc = spdk_thread_send_msg(thr, nvmf_rdma_qpair_process_ibv_event, ctx);
3045 	if (rc) {
3046 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3047 		free(ctx);
3048 	}
3049 
3050 	return rc;
3051 }
3052 
3053 static int
3054 nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
3055 {
3056 	int				rc;
3057 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
3058 	struct ibv_async_event		event;
3059 
3060 	rc = ibv_get_async_event(device->context, &event);
3061 
3062 	if (rc) {
3063 		/* In non-blocking mode -1 means there are no events available */
3064 		return rc;
3065 	}
3066 
3067 	switch (event.event_type) {
3068 	case IBV_EVENT_QP_FATAL:
3069 		rqpair = event.element.qp->qp_context;
3070 		SPDK_ERRLOG("Fatal event received for rqpair %p\n", rqpair);
3071 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3072 				  (uintptr_t)rqpair->cm_id, event.event_type);
3073 		nvmf_rdma_update_ibv_state(rqpair);
3074 		spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3075 		break;
3076 	case IBV_EVENT_QP_LAST_WQE_REACHED:
3077 		/* This event only occurs for shared receive queues. */
3078 		rqpair = event.element.qp->qp_context;
3079 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Last WQE reached event received for rqpair %p\n", rqpair);
3080 		rc = nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_last_wqe_reached);
3081 		if (rc) {
3082 			SPDK_WARNLOG("Failed to send LAST_WQE_REACHED event. rqpair %p, err %d\n", rqpair, rc);
3083 			rqpair->last_wqe_reached = true;
3084 		}
3085 		break;
3086 	case IBV_EVENT_SQ_DRAINED:
3087 		/* This event occurs frequently in both error and non-error states.
3088 		 * Check if the qpair is in an error state before sending a message. */
3089 		rqpair = event.element.qp->qp_context;
3090 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Last sq drained event received for rqpair %p\n", rqpair);
3091 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3092 				  (uintptr_t)rqpair->cm_id, event.event_type);
3093 		if (nvmf_rdma_update_ibv_state(rqpair) == IBV_QPS_ERR) {
3094 			spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3095 		}
3096 		break;
3097 	case IBV_EVENT_QP_REQ_ERR:
3098 	case IBV_EVENT_QP_ACCESS_ERR:
3099 	case IBV_EVENT_COMM_EST:
3100 	case IBV_EVENT_PATH_MIG:
3101 	case IBV_EVENT_PATH_MIG_ERR:
3102 		SPDK_NOTICELOG("Async event: %s\n",
3103 			       ibv_event_type_str(event.event_type));
3104 		rqpair = event.element.qp->qp_context;
3105 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3106 				  (uintptr_t)rqpair->cm_id, event.event_type);
3107 		nvmf_rdma_update_ibv_state(rqpair);
3108 		break;
3109 	case IBV_EVENT_CQ_ERR:
3110 	case IBV_EVENT_DEVICE_FATAL:
3111 	case IBV_EVENT_PORT_ACTIVE:
3112 	case IBV_EVENT_PORT_ERR:
3113 	case IBV_EVENT_LID_CHANGE:
3114 	case IBV_EVENT_PKEY_CHANGE:
3115 	case IBV_EVENT_SM_CHANGE:
3116 	case IBV_EVENT_SRQ_ERR:
3117 	case IBV_EVENT_SRQ_LIMIT_REACHED:
3118 	case IBV_EVENT_CLIENT_REREGISTER:
3119 	case IBV_EVENT_GID_CHANGE:
3120 	default:
3121 		SPDK_NOTICELOG("Async event: %s\n",
3122 			       ibv_event_type_str(event.event_type));
3123 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
3124 		break;
3125 	}
3126 	ibv_ack_async_event(&event);
3127 
3128 	return 0;
3129 }
3130 
3131 static void
3132 nvmf_process_ib_events(struct spdk_nvmf_rdma_device *device, uint32_t max_events)
3133 {
3134 	int rc = 0;
3135 	uint32_t i = 0;
3136 
3137 	for (i = 0; i < max_events; i++) {
3138 		rc = nvmf_process_ib_event(device);
3139 		if (rc) {
3140 			break;
3141 		}
3142 	}
3143 
3144 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Device %s: %u events processed\n", device->context->device->name, i);
3145 }
3146 
3147 static uint32_t
3148 nvmf_rdma_accept(struct spdk_nvmf_transport *transport)
3149 {
3150 	int	nfds, i = 0;
3151 	struct spdk_nvmf_rdma_transport *rtransport;
3152 	struct spdk_nvmf_rdma_device *device, *tmp;
3153 	uint32_t count;
3154 
3155 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3156 	count = nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
3157 
3158 	if (nfds <= 0) {
3159 		return 0;
3160 	}
3161 
3162 	/* The first poll descriptor is RDMA CM event */
3163 	if (rtransport->poll_fds[i++].revents & POLLIN) {
3164 		nvmf_process_cm_event(transport);
3165 		nfds--;
3166 	}
3167 
3168 	if (nfds == 0) {
3169 		return count;
3170 	}
3171 
3172 	/* Second and subsequent poll descriptors are IB async events */
3173 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
3174 		if (rtransport->poll_fds[i++].revents & POLLIN) {
3175 			nvmf_process_ib_events(device, 32);
3176 			nfds--;
3177 		}
3178 	}
3179 	/* check all flagged fd's have been served */
3180 	assert(nfds == 0);
3181 
3182 	return count;
3183 }
3184 
3185 static void
3186 nvmf_rdma_cdata_init(struct spdk_nvmf_transport *transport, struct spdk_nvmf_subsystem *subsystem,
3187 		     struct spdk_nvmf_ctrlr_data *cdata)
3188 {
3189 	cdata->nvmf_specific.msdbd = SPDK_NVMF_MAX_SGL_ENTRIES;
3190 
3191 	/* Disable in-capsule data transfer for RDMA controller when dif_insert_or_strip is enabled
3192 	since in-capsule data only works with NVME drives that support SGL memory layout */
3193 	if (transport->opts.dif_insert_or_strip) {
3194 		cdata->nvmf_specific.ioccsz = sizeof(struct spdk_nvme_cmd) / 16;
3195 	}
3196 }
3197 
3198 static void
3199 nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
3200 		   struct spdk_nvme_transport_id *trid,
3201 		   struct spdk_nvmf_discovery_log_page_entry *entry)
3202 {
3203 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
3204 	entry->adrfam = trid->adrfam;
3205 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
3206 
3207 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
3208 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
3209 
3210 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
3211 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
3212 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
3213 }
3214 
3215 static void
3216 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
3217 
3218 static struct spdk_nvmf_transport_poll_group *
3219 nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
3220 {
3221 	struct spdk_nvmf_rdma_transport		*rtransport;
3222 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3223 	struct spdk_nvmf_rdma_poller		*poller;
3224 	struct spdk_nvmf_rdma_device		*device;
3225 	struct ibv_srq_init_attr		srq_init_attr;
3226 	struct spdk_nvmf_rdma_resource_opts	opts;
3227 	int					num_cqe;
3228 
3229 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3230 
3231 	rgroup = calloc(1, sizeof(*rgroup));
3232 	if (!rgroup) {
3233 		return NULL;
3234 	}
3235 
3236 	TAILQ_INIT(&rgroup->pollers);
3237 	STAILQ_INIT(&rgroup->retired_bufs);
3238 
3239 	pthread_mutex_lock(&rtransport->lock);
3240 	TAILQ_FOREACH(device, &rtransport->devices, link) {
3241 		poller = calloc(1, sizeof(*poller));
3242 		if (!poller) {
3243 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
3244 			nvmf_rdma_poll_group_destroy(&rgroup->group);
3245 			pthread_mutex_unlock(&rtransport->lock);
3246 			return NULL;
3247 		}
3248 
3249 		poller->device = device;
3250 		poller->group = rgroup;
3251 
3252 		TAILQ_INIT(&poller->qpairs);
3253 		STAILQ_INIT(&poller->qpairs_pending_send);
3254 		STAILQ_INIT(&poller->qpairs_pending_recv);
3255 
3256 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
3257 		if (transport->opts.no_srq == false && device->num_srq < device->attr.max_srq) {
3258 			poller->max_srq_depth = transport->opts.max_srq_depth;
3259 
3260 			device->num_srq++;
3261 			memset(&srq_init_attr, 0, sizeof(struct ibv_srq_init_attr));
3262 			srq_init_attr.attr.max_wr = poller->max_srq_depth;
3263 			srq_init_attr.attr.max_sge = spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
3264 			poller->srq = ibv_create_srq(device->pd, &srq_init_attr);
3265 			if (!poller->srq) {
3266 				SPDK_ERRLOG("Unable to create shared receive queue, errno %d\n", errno);
3267 				nvmf_rdma_poll_group_destroy(&rgroup->group);
3268 				pthread_mutex_unlock(&rtransport->lock);
3269 				return NULL;
3270 			}
3271 
3272 			opts.qp = poller->srq;
3273 			opts.pd = device->pd;
3274 			opts.qpair = NULL;
3275 			opts.shared = true;
3276 			opts.max_queue_depth = poller->max_srq_depth;
3277 			opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
3278 
3279 			poller->resources = nvmf_rdma_resources_create(&opts);
3280 			if (!poller->resources) {
3281 				SPDK_ERRLOG("Unable to allocate resources for shared receive queue.\n");
3282 				nvmf_rdma_poll_group_destroy(&rgroup->group);
3283 				pthread_mutex_unlock(&rtransport->lock);
3284 				return NULL;
3285 			}
3286 		}
3287 
3288 		/*
3289 		 * When using an srq, we can limit the completion queue at startup.
3290 		 * The following formula represents the calculation:
3291 		 * num_cqe = num_recv + num_data_wr + num_send_wr.
3292 		 * where num_recv=num_data_wr=and num_send_wr=poller->max_srq_depth
3293 		 */
3294 		if (poller->srq) {
3295 			num_cqe = poller->max_srq_depth * 3;
3296 		} else {
3297 			num_cqe = DEFAULT_NVMF_RDMA_CQ_SIZE;
3298 		}
3299 
3300 		poller->cq = ibv_create_cq(device->context, num_cqe, poller, NULL, 0);
3301 		if (!poller->cq) {
3302 			SPDK_ERRLOG("Unable to create completion queue\n");
3303 			nvmf_rdma_poll_group_destroy(&rgroup->group);
3304 			pthread_mutex_unlock(&rtransport->lock);
3305 			return NULL;
3306 		}
3307 		poller->num_cqe = num_cqe;
3308 	}
3309 
3310 	TAILQ_INSERT_TAIL(&rtransport->poll_groups, rgroup, link);
3311 	if (rtransport->conn_sched.next_admin_pg == NULL) {
3312 		rtransport->conn_sched.next_admin_pg = rgroup;
3313 		rtransport->conn_sched.next_io_pg = rgroup;
3314 	}
3315 
3316 	pthread_mutex_unlock(&rtransport->lock);
3317 	return &rgroup->group;
3318 }
3319 
3320 static struct spdk_nvmf_transport_poll_group *
3321 nvmf_rdma_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
3322 {
3323 	struct spdk_nvmf_rdma_transport *rtransport;
3324 	struct spdk_nvmf_rdma_poll_group **pg;
3325 	struct spdk_nvmf_transport_poll_group *result;
3326 
3327 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
3328 
3329 	pthread_mutex_lock(&rtransport->lock);
3330 
3331 	if (TAILQ_EMPTY(&rtransport->poll_groups)) {
3332 		pthread_mutex_unlock(&rtransport->lock);
3333 		return NULL;
3334 	}
3335 
3336 	if (qpair->qid == 0) {
3337 		pg = &rtransport->conn_sched.next_admin_pg;
3338 	} else {
3339 		pg = &rtransport->conn_sched.next_io_pg;
3340 	}
3341 
3342 	assert(*pg != NULL);
3343 
3344 	result = &(*pg)->group;
3345 
3346 	*pg = TAILQ_NEXT(*pg, link);
3347 	if (*pg == NULL) {
3348 		*pg = TAILQ_FIRST(&rtransport->poll_groups);
3349 	}
3350 
3351 	pthread_mutex_unlock(&rtransport->lock);
3352 
3353 	return result;
3354 }
3355 
3356 static void
3357 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
3358 {
3359 	struct spdk_nvmf_rdma_poll_group	*rgroup, *next_rgroup;
3360 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
3361 	struct spdk_nvmf_rdma_qpair		*qpair, *tmp_qpair;
3362 	struct spdk_nvmf_transport_pg_cache_buf	*buf, *tmp_buf;
3363 	struct spdk_nvmf_rdma_transport		*rtransport;
3364 
3365 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3366 	if (!rgroup) {
3367 		return;
3368 	}
3369 
3370 	/* free all retired buffers back to the transport so we don't short the mempool. */
3371 	STAILQ_FOREACH_SAFE(buf, &rgroup->retired_bufs, link, tmp_buf) {
3372 		STAILQ_REMOVE(&rgroup->retired_bufs, buf, spdk_nvmf_transport_pg_cache_buf, link);
3373 		assert(group->transport != NULL);
3374 		spdk_mempool_put(group->transport->data_buf_pool, buf);
3375 	}
3376 
3377 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
3378 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
3379 
3380 		TAILQ_FOREACH_SAFE(qpair, &poller->qpairs, link, tmp_qpair) {
3381 			nvmf_rdma_qpair_destroy(qpair);
3382 		}
3383 
3384 		if (poller->srq) {
3385 			if (poller->resources) {
3386 				nvmf_rdma_resources_destroy(poller->resources);
3387 			}
3388 			ibv_destroy_srq(poller->srq);
3389 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Destroyed RDMA shared queue %p\n", poller->srq);
3390 		}
3391 
3392 		if (poller->cq) {
3393 			ibv_destroy_cq(poller->cq);
3394 		}
3395 
3396 		free(poller);
3397 	}
3398 
3399 	if (rgroup->group.transport == NULL) {
3400 		/* Transport can be NULL when nvmf_rdma_poll_group_create()
3401 		 * calls this function directly in a failure path. */
3402 		free(rgroup);
3403 		return;
3404 	}
3405 
3406 	rtransport = SPDK_CONTAINEROF(rgroup->group.transport, struct spdk_nvmf_rdma_transport, transport);
3407 
3408 	pthread_mutex_lock(&rtransport->lock);
3409 	next_rgroup = TAILQ_NEXT(rgroup, link);
3410 	TAILQ_REMOVE(&rtransport->poll_groups, rgroup, link);
3411 	if (next_rgroup == NULL) {
3412 		next_rgroup = TAILQ_FIRST(&rtransport->poll_groups);
3413 	}
3414 	if (rtransport->conn_sched.next_admin_pg == rgroup) {
3415 		rtransport->conn_sched.next_admin_pg = next_rgroup;
3416 	}
3417 	if (rtransport->conn_sched.next_io_pg == rgroup) {
3418 		rtransport->conn_sched.next_io_pg = next_rgroup;
3419 	}
3420 	pthread_mutex_unlock(&rtransport->lock);
3421 
3422 	free(rgroup);
3423 }
3424 
3425 static void
3426 nvmf_rdma_qpair_reject_connection(struct spdk_nvmf_rdma_qpair *rqpair)
3427 {
3428 	if (rqpair->cm_id != NULL) {
3429 		nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
3430 	}
3431 }
3432 
3433 static int
3434 nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
3435 			 struct spdk_nvmf_qpair *qpair)
3436 {
3437 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3438 	struct spdk_nvmf_rdma_qpair		*rqpair;
3439 	struct spdk_nvmf_rdma_device		*device;
3440 	struct spdk_nvmf_rdma_poller		*poller;
3441 	int					rc;
3442 
3443 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3444 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3445 
3446 	device = rqpair->device;
3447 
3448 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
3449 		if (poller->device == device) {
3450 			break;
3451 		}
3452 	}
3453 
3454 	if (!poller) {
3455 		SPDK_ERRLOG("No poller found for device.\n");
3456 		return -1;
3457 	}
3458 
3459 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
3460 	rqpair->poller = poller;
3461 	rqpair->srq = rqpair->poller->srq;
3462 
3463 	rc = nvmf_rdma_qpair_initialize(qpair);
3464 	if (rc < 0) {
3465 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
3466 		return -1;
3467 	}
3468 
3469 	rc = nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
3470 	if (rc) {
3471 		/* Try to reject, but we probably can't */
3472 		nvmf_rdma_qpair_reject_connection(rqpair);
3473 		return -1;
3474 	}
3475 
3476 	nvmf_rdma_update_ibv_state(rqpair);
3477 
3478 	return 0;
3479 }
3480 
3481 static int
3482 nvmf_rdma_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
3483 			    struct spdk_nvmf_qpair *qpair)
3484 {
3485 	struct spdk_nvmf_rdma_qpair		*rqpair;
3486 
3487 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3488 	assert(group->transport->tgt != NULL);
3489 
3490 	rqpair->destruct_channel = spdk_get_io_channel(group->transport->tgt);
3491 
3492 	if (!rqpair->destruct_channel) {
3493 		SPDK_WARNLOG("failed to get io_channel, qpair %p\n", qpair);
3494 		return 0;
3495 	}
3496 
3497 	/* Sanity check that we get io_channel on the correct thread */
3498 	if (qpair->group) {
3499 		assert(qpair->group->thread == spdk_io_channel_get_thread(rqpair->destruct_channel));
3500 	}
3501 
3502 	return 0;
3503 }
3504 
3505 static int
3506 nvmf_rdma_request_free(struct spdk_nvmf_request *req)
3507 {
3508 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
3509 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3510 			struct spdk_nvmf_rdma_transport, transport);
3511 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3512 					      struct spdk_nvmf_rdma_qpair, qpair);
3513 
3514 	/*
3515 	 * AER requests are freed when a qpair is destroyed. The recv corresponding to that request
3516 	 * needs to be returned to the shared receive queue or the poll group will eventually be
3517 	 * starved of RECV structures.
3518 	 */
3519 	if (rqpair->srq && rdma_req->recv) {
3520 		int rc;
3521 		struct ibv_recv_wr *bad_recv_wr;
3522 
3523 		rc = ibv_post_srq_recv(rqpair->srq, &rdma_req->recv->wr, &bad_recv_wr);
3524 		if (rc) {
3525 			SPDK_ERRLOG("Unable to re-post rx descriptor\n");
3526 		}
3527 	}
3528 
3529 	_nvmf_rdma_request_free(rdma_req, rtransport);
3530 	return 0;
3531 }
3532 
3533 static int
3534 nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
3535 {
3536 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3537 			struct spdk_nvmf_rdma_transport, transport);
3538 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
3539 			struct spdk_nvmf_rdma_request, req);
3540 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3541 			struct spdk_nvmf_rdma_qpair, qpair);
3542 
3543 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3544 		/* The connection is alive, so process the request as normal */
3545 		rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
3546 	} else {
3547 		/* The connection is dead. Move the request directly to the completed state. */
3548 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3549 	}
3550 
3551 	nvmf_rdma_request_process(rtransport, rdma_req);
3552 
3553 	return 0;
3554 }
3555 
3556 static void
3557 nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair)
3558 {
3559 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3560 
3561 	rqpair->to_close = true;
3562 
3563 	/* This happens only when the qpair is disconnected before
3564 	 * it is added to the poll group. Since there is no poll group,
3565 	 * the RDMA qp has not been initialized yet and the RDMA CM
3566 	 * event has not yet been acknowledged, so we need to reject it.
3567 	 */
3568 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
3569 		nvmf_rdma_qpair_reject_connection(rqpair);
3570 		nvmf_rdma_qpair_destroy(rqpair);
3571 		return;
3572 	}
3573 
3574 	if (rqpair->rdma_qp) {
3575 		spdk_rdma_qp_disconnect(rqpair->rdma_qp);
3576 	}
3577 
3578 	nvmf_rdma_destroy_drained_qpair(rqpair);
3579 }
3580 
3581 static struct spdk_nvmf_rdma_qpair *
3582 get_rdma_qpair_from_wc(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_wc *wc)
3583 {
3584 	struct spdk_nvmf_rdma_qpair *rqpair;
3585 	/* @todo: improve QP search */
3586 	TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
3587 		if (wc->qp_num == rqpair->rdma_qp->qp->qp_num) {
3588 			return rqpair;
3589 		}
3590 	}
3591 	SPDK_ERRLOG("Didn't find QP with qp_num %u\n", wc->qp_num);
3592 	return NULL;
3593 }
3594 
3595 #ifdef DEBUG
3596 static int
3597 nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
3598 {
3599 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
3600 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
3601 }
3602 #endif
3603 
3604 static void
3605 _poller_reset_failed_recvs(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_recv_wr *bad_recv_wr,
3606 			   int rc)
3607 {
3608 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3609 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3610 
3611 	SPDK_ERRLOG("Failed to post a recv for the poller %p with errno %d\n", rpoller, -rc);
3612 	while (bad_recv_wr != NULL) {
3613 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_recv_wr->wr_id;
3614 		rdma_recv = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3615 
3616 		rdma_recv->qpair->current_recv_depth++;
3617 		bad_recv_wr = bad_recv_wr->next;
3618 		SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rdma_recv->qpair, -rc);
3619 		spdk_nvmf_qpair_disconnect(&rdma_recv->qpair->qpair, NULL, NULL);
3620 	}
3621 }
3622 
3623 static void
3624 _qp_reset_failed_recvs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *bad_recv_wr, int rc)
3625 {
3626 	SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rqpair, -rc);
3627 	while (bad_recv_wr != NULL) {
3628 		bad_recv_wr = bad_recv_wr->next;
3629 		rqpair->current_recv_depth++;
3630 	}
3631 	spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3632 }
3633 
3634 static void
3635 _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
3636 		     struct spdk_nvmf_rdma_poller *rpoller)
3637 {
3638 	struct spdk_nvmf_rdma_qpair	*rqpair;
3639 	struct ibv_recv_wr		*bad_recv_wr;
3640 	int				rc;
3641 
3642 	if (rpoller->srq) {
3643 		if (rpoller->resources->recvs_to_post.first != NULL) {
3644 			rc = ibv_post_srq_recv(rpoller->srq, rpoller->resources->recvs_to_post.first, &bad_recv_wr);
3645 			if (rc) {
3646 				_poller_reset_failed_recvs(rpoller, bad_recv_wr, rc);
3647 			}
3648 			rpoller->resources->recvs_to_post.first = NULL;
3649 			rpoller->resources->recvs_to_post.last = NULL;
3650 		}
3651 	} else {
3652 		while (!STAILQ_EMPTY(&rpoller->qpairs_pending_recv)) {
3653 			rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_recv);
3654 			assert(rqpair->resources->recvs_to_post.first != NULL);
3655 			rc = ibv_post_recv(rqpair->rdma_qp->qp, rqpair->resources->recvs_to_post.first, &bad_recv_wr);
3656 			if (rc) {
3657 				_qp_reset_failed_recvs(rqpair, bad_recv_wr, rc);
3658 			}
3659 			rqpair->resources->recvs_to_post.first = NULL;
3660 			rqpair->resources->recvs_to_post.last = NULL;
3661 			STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_recv, recv_link);
3662 		}
3663 	}
3664 }
3665 
3666 static void
3667 _qp_reset_failed_sends(struct spdk_nvmf_rdma_transport *rtransport,
3668 		       struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_send_wr *bad_wr, int rc)
3669 {
3670 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3671 	struct spdk_nvmf_rdma_request	*prev_rdma_req = NULL, *cur_rdma_req = NULL;
3672 
3673 	SPDK_ERRLOG("Failed to post a send for the qpair %p with errno %d\n", rqpair, -rc);
3674 	for (; bad_wr != NULL; bad_wr = bad_wr->next) {
3675 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_wr->wr_id;
3676 		assert(rqpair->current_send_depth > 0);
3677 		rqpair->current_send_depth--;
3678 		switch (bad_rdma_wr->type) {
3679 		case RDMA_WR_TYPE_DATA:
3680 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3681 			if (bad_wr->opcode == IBV_WR_RDMA_READ) {
3682 				assert(rqpair->current_read_depth > 0);
3683 				rqpair->current_read_depth--;
3684 			}
3685 			break;
3686 		case RDMA_WR_TYPE_SEND:
3687 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3688 			break;
3689 		default:
3690 			SPDK_ERRLOG("Found a RECV in the list of pending SEND requests for qpair %p\n", rqpair);
3691 			prev_rdma_req = cur_rdma_req;
3692 			continue;
3693 		}
3694 
3695 		if (prev_rdma_req == cur_rdma_req) {
3696 			/* this request was handled by an earlier wr. i.e. we were performing an nvme read. */
3697 			/* We only have to check against prev_wr since each requests wrs are contiguous in this list. */
3698 			continue;
3699 		}
3700 
3701 		switch (cur_rdma_req->state) {
3702 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
3703 			cur_rdma_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
3704 			cur_rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
3705 			break;
3706 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
3707 		case RDMA_REQUEST_STATE_COMPLETING:
3708 			cur_rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3709 			break;
3710 		default:
3711 			SPDK_ERRLOG("Found a request in a bad state %d when draining pending SEND requests for qpair %p\n",
3712 				    cur_rdma_req->state, rqpair);
3713 			continue;
3714 		}
3715 
3716 		nvmf_rdma_request_process(rtransport, cur_rdma_req);
3717 		prev_rdma_req = cur_rdma_req;
3718 	}
3719 
3720 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3721 		/* Disconnect the connection. */
3722 		spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3723 	}
3724 
3725 }
3726 
3727 static void
3728 _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
3729 		     struct spdk_nvmf_rdma_poller *rpoller)
3730 {
3731 	struct spdk_nvmf_rdma_qpair	*rqpair;
3732 	struct ibv_send_wr		*bad_wr = NULL;
3733 	int				rc;
3734 
3735 	while (!STAILQ_EMPTY(&rpoller->qpairs_pending_send)) {
3736 		rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_send);
3737 		rc = spdk_rdma_qp_flush_send_wrs(rqpair->rdma_qp, &bad_wr);
3738 
3739 		/* bad wr always points to the first wr that failed. */
3740 		if (rc) {
3741 			_qp_reset_failed_sends(rtransport, rqpair, bad_wr, rc);
3742 		}
3743 		STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_send, send_link);
3744 	}
3745 }
3746 
3747 static const char *
3748 nvmf_rdma_wr_type_str(enum spdk_nvmf_rdma_wr_type wr_type)
3749 {
3750 	switch (wr_type) {
3751 	case RDMA_WR_TYPE_RECV:
3752 		return "RECV";
3753 	case RDMA_WR_TYPE_SEND:
3754 		return "SEND";
3755 	case RDMA_WR_TYPE_DATA:
3756 		return "DATA";
3757 	default:
3758 		SPDK_ERRLOG("Unknown WR type %d\n", wr_type);
3759 		SPDK_UNREACHABLE();
3760 	}
3761 }
3762 
3763 static inline void
3764 nvmf_rdma_log_wc_status(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_wc *wc)
3765 {
3766 	enum spdk_nvmf_rdma_wr_type wr_type = ((struct spdk_nvmf_rdma_wr *)wc->wr_id)->type;
3767 
3768 	if (wc->status == IBV_WC_WR_FLUSH_ERR) {
3769 		/* If qpair is in ERR state, we will receive completions for all posted and not completed
3770 		 * Work Requests with IBV_WC_WR_FLUSH_ERR status. Don't log an error in that case */
3771 		SPDK_DEBUGLOG(SPDK_LOG_RDMA,
3772 			      "Error on CQ %p, (qp state %d ibv_state %d) request 0x%lu, type %s, status: (%d): %s\n",
3773 			      rqpair->poller->cq, rqpair->qpair.state, rqpair->ibv_state, wc->wr_id,
3774 			      nvmf_rdma_wr_type_str(wr_type), wc->status, ibv_wc_status_str(wc->status));
3775 	} else {
3776 		SPDK_ERRLOG("Error on CQ %p, (qp state %d ibv_state %d) request 0x%lu, type %s, status: (%d): %s\n",
3777 			    rqpair->poller->cq, rqpair->qpair.state, rqpair->ibv_state, wc->wr_id,
3778 			    nvmf_rdma_wr_type_str(wr_type), wc->status, ibv_wc_status_str(wc->status));
3779 	}
3780 }
3781 
3782 static int
3783 nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
3784 		      struct spdk_nvmf_rdma_poller *rpoller)
3785 {
3786 	struct ibv_wc wc[32];
3787 	struct spdk_nvmf_rdma_wr	*rdma_wr;
3788 	struct spdk_nvmf_rdma_request	*rdma_req;
3789 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3790 	struct spdk_nvmf_rdma_qpair	*rqpair;
3791 	int reaped, i;
3792 	int count = 0;
3793 	bool error = false;
3794 	uint64_t poll_tsc = spdk_get_ticks();
3795 
3796 	/* Poll for completing operations. */
3797 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
3798 	if (reaped < 0) {
3799 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
3800 			    errno, spdk_strerror(errno));
3801 		return -1;
3802 	}
3803 
3804 	rpoller->stat.polls++;
3805 	rpoller->stat.completions += reaped;
3806 
3807 	for (i = 0; i < reaped; i++) {
3808 
3809 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
3810 
3811 		switch (rdma_wr->type) {
3812 		case RDMA_WR_TYPE_SEND:
3813 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3814 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3815 
3816 			if (!wc[i].status) {
3817 				count++;
3818 				assert(wc[i].opcode == IBV_WC_SEND);
3819 				assert(nvmf_rdma_req_is_completing(rdma_req));
3820 			}
3821 
3822 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3823 			/* RDMA_WRITE operation completed. +1 since it was chained with rsp WR */
3824 			rqpair->current_send_depth -= rdma_req->num_outstanding_data_wr + 1;
3825 			rdma_req->num_outstanding_data_wr = 0;
3826 
3827 			nvmf_rdma_request_process(rtransport, rdma_req);
3828 			break;
3829 		case RDMA_WR_TYPE_RECV:
3830 			/* rdma_recv->qpair will be invalid if using an SRQ.  In that case we have to get the qpair from the wc. */
3831 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3832 			if (rpoller->srq != NULL) {
3833 				rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
3834 				/* It is possible that there are still some completions for destroyed QP
3835 				 * associated with SRQ. We just ignore these late completions and re-post
3836 				 * receive WRs back to SRQ.
3837 				 */
3838 				if (spdk_unlikely(NULL == rdma_recv->qpair)) {
3839 					struct ibv_recv_wr *bad_wr;
3840 					int rc;
3841 
3842 					rdma_recv->wr.next = NULL;
3843 					rc = ibv_post_srq_recv(rpoller->srq,
3844 							       &rdma_recv->wr,
3845 							       &bad_wr);
3846 					if (rc) {
3847 						SPDK_ERRLOG("Failed to re-post recv WR to SRQ, err %d\n", rc);
3848 					}
3849 					continue;
3850 				}
3851 			}
3852 			rqpair = rdma_recv->qpair;
3853 
3854 			assert(rqpair != NULL);
3855 			if (!wc[i].status) {
3856 				assert(wc[i].opcode == IBV_WC_RECV);
3857 				if (rqpair->current_recv_depth >= rqpair->max_queue_depth) {
3858 					spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3859 					break;
3860 				}
3861 			}
3862 
3863 			rdma_recv->wr.next = NULL;
3864 			rqpair->current_recv_depth++;
3865 			rdma_recv->receive_tsc = poll_tsc;
3866 			rpoller->stat.requests++;
3867 			STAILQ_INSERT_TAIL(&rqpair->resources->incoming_queue, rdma_recv, link);
3868 			break;
3869 		case RDMA_WR_TYPE_DATA:
3870 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3871 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3872 
3873 			assert(rdma_req->num_outstanding_data_wr > 0);
3874 
3875 			rqpair->current_send_depth--;
3876 			rdma_req->num_outstanding_data_wr--;
3877 			if (!wc[i].status) {
3878 				assert(wc[i].opcode == IBV_WC_RDMA_READ);
3879 				rqpair->current_read_depth--;
3880 				/* wait for all outstanding reads associated with the same rdma_req to complete before proceeding. */
3881 				if (rdma_req->num_outstanding_data_wr == 0) {
3882 					rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
3883 					nvmf_rdma_request_process(rtransport, rdma_req);
3884 				}
3885 			} else {
3886 				/* If the data transfer fails still force the queue into the error state,
3887 				 * if we were performing an RDMA_READ, we need to force the request into a
3888 				 * completed state since it wasn't linked to a send. However, in the RDMA_WRITE
3889 				 * case, we should wait for the SEND to complete. */
3890 				if (rdma_req->data.wr.opcode == IBV_WR_RDMA_READ) {
3891 					rqpair->current_read_depth--;
3892 					if (rdma_req->num_outstanding_data_wr == 0) {
3893 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3894 					}
3895 				}
3896 			}
3897 			break;
3898 		default:
3899 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
3900 			continue;
3901 		}
3902 
3903 		/* Handle error conditions */
3904 		if (wc[i].status) {
3905 			nvmf_rdma_update_ibv_state(rqpair);
3906 			nvmf_rdma_log_wc_status(rqpair, &wc[i]);
3907 
3908 			error = true;
3909 
3910 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3911 				/* Disconnect the connection. */
3912 				spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3913 			} else {
3914 				nvmf_rdma_destroy_drained_qpair(rqpair);
3915 			}
3916 			continue;
3917 		}
3918 
3919 		nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3920 
3921 		if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
3922 			nvmf_rdma_destroy_drained_qpair(rqpair);
3923 		}
3924 	}
3925 
3926 	if (error == true) {
3927 		return -1;
3928 	}
3929 
3930 	/* submit outstanding work requests. */
3931 	_poller_submit_recvs(rtransport, rpoller);
3932 	_poller_submit_sends(rtransport, rpoller);
3933 
3934 	return count;
3935 }
3936 
3937 static int
3938 nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3939 {
3940 	struct spdk_nvmf_rdma_transport *rtransport;
3941 	struct spdk_nvmf_rdma_poll_group *rgroup;
3942 	struct spdk_nvmf_rdma_poller	*rpoller;
3943 	int				count, rc;
3944 
3945 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
3946 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3947 
3948 	count = 0;
3949 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3950 		rc = nvmf_rdma_poller_poll(rtransport, rpoller);
3951 		if (rc < 0) {
3952 			return rc;
3953 		}
3954 		count += rc;
3955 	}
3956 
3957 	return count;
3958 }
3959 
3960 static int
3961 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
3962 			  struct spdk_nvme_transport_id *trid,
3963 			  bool peer)
3964 {
3965 	struct sockaddr *saddr;
3966 	uint16_t port;
3967 
3968 	spdk_nvme_trid_populate_transport(trid, SPDK_NVME_TRANSPORT_RDMA);
3969 
3970 	if (peer) {
3971 		saddr = rdma_get_peer_addr(id);
3972 	} else {
3973 		saddr = rdma_get_local_addr(id);
3974 	}
3975 	switch (saddr->sa_family) {
3976 	case AF_INET: {
3977 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
3978 
3979 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3980 		inet_ntop(AF_INET, &saddr_in->sin_addr,
3981 			  trid->traddr, sizeof(trid->traddr));
3982 		if (peer) {
3983 			port = ntohs(rdma_get_dst_port(id));
3984 		} else {
3985 			port = ntohs(rdma_get_src_port(id));
3986 		}
3987 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3988 		break;
3989 	}
3990 	case AF_INET6: {
3991 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
3992 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3993 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
3994 			  trid->traddr, sizeof(trid->traddr));
3995 		if (peer) {
3996 			port = ntohs(rdma_get_dst_port(id));
3997 		} else {
3998 			port = ntohs(rdma_get_src_port(id));
3999 		}
4000 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
4001 		break;
4002 	}
4003 	default:
4004 		return -1;
4005 
4006 	}
4007 
4008 	return 0;
4009 }
4010 
4011 static int
4012 nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
4013 			      struct spdk_nvme_transport_id *trid)
4014 {
4015 	struct spdk_nvmf_rdma_qpair	*rqpair;
4016 
4017 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4018 
4019 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
4020 }
4021 
4022 static int
4023 nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
4024 			       struct spdk_nvme_transport_id *trid)
4025 {
4026 	struct spdk_nvmf_rdma_qpair	*rqpair;
4027 
4028 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4029 
4030 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
4031 }
4032 
4033 static int
4034 nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
4035 				struct spdk_nvme_transport_id *trid)
4036 {
4037 	struct spdk_nvmf_rdma_qpair	*rqpair;
4038 
4039 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4040 
4041 	return nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
4042 }
4043 
4044 void
4045 spdk_nvmf_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
4046 {
4047 	g_nvmf_hooks = *hooks;
4048 }
4049 
4050 static void
4051 nvmf_rdma_request_set_abort_status(struct spdk_nvmf_request *req,
4052 				   struct spdk_nvmf_rdma_request *rdma_req_to_abort)
4053 {
4054 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
4055 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_BY_REQUEST;
4056 
4057 	rdma_req_to_abort->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
4058 
4059 	req->rsp->nvme_cpl.cdw0 &= ~1U;	/* Command was successfully aborted. */
4060 }
4061 
4062 static int
4063 _nvmf_rdma_qpair_abort_request(void *ctx)
4064 {
4065 	struct spdk_nvmf_request *req = ctx;
4066 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = SPDK_CONTAINEROF(
4067 				req->req_to_abort, struct spdk_nvmf_rdma_request, req);
4068 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(req->req_to_abort->qpair,
4069 					      struct spdk_nvmf_rdma_qpair, qpair);
4070 	int rc;
4071 
4072 	spdk_poller_unregister(&req->poller);
4073 
4074 	switch (rdma_req_to_abort->state) {
4075 	case RDMA_REQUEST_STATE_EXECUTING:
4076 		rc = nvmf_ctrlr_abort_request(req);
4077 		if (rc == SPDK_NVMF_REQUEST_EXEC_STATUS_ASYNCHRONOUS) {
4078 			return SPDK_POLLER_BUSY;
4079 		}
4080 		break;
4081 
4082 	case RDMA_REQUEST_STATE_NEED_BUFFER:
4083 		STAILQ_REMOVE(&rqpair->poller->group->group.pending_buf_queue,
4084 			      &rdma_req_to_abort->req, spdk_nvmf_request, buf_link);
4085 
4086 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4087 		break;
4088 
4089 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
4090 		STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req_to_abort,
4091 			      spdk_nvmf_rdma_request, state_link);
4092 
4093 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4094 		break;
4095 
4096 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
4097 		STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req_to_abort,
4098 			      spdk_nvmf_rdma_request, state_link);
4099 
4100 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4101 		break;
4102 
4103 	case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
4104 		if (spdk_get_ticks() < req->timeout_tsc) {
4105 			req->poller = SPDK_POLLER_REGISTER(_nvmf_rdma_qpair_abort_request, req, 0);
4106 			return SPDK_POLLER_BUSY;
4107 		}
4108 		break;
4109 
4110 	default:
4111 		break;
4112 	}
4113 
4114 	spdk_nvmf_request_complete(req);
4115 	return SPDK_POLLER_BUSY;
4116 }
4117 
4118 static void
4119 nvmf_rdma_qpair_abort_request(struct spdk_nvmf_qpair *qpair,
4120 			      struct spdk_nvmf_request *req)
4121 {
4122 	struct spdk_nvmf_rdma_qpair *rqpair;
4123 	struct spdk_nvmf_rdma_transport *rtransport;
4124 	struct spdk_nvmf_transport *transport;
4125 	uint16_t cid;
4126 	uint32_t i;
4127 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = NULL;
4128 
4129 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4130 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
4131 	transport = &rtransport->transport;
4132 
4133 	cid = req->cmd->nvme_cmd.cdw10_bits.abort.cid;
4134 
4135 	for (i = 0; i < rqpair->max_queue_depth; i++) {
4136 		rdma_req_to_abort = &rqpair->resources->reqs[i];
4137 
4138 		if (rdma_req_to_abort->state != RDMA_REQUEST_STATE_FREE &&
4139 		    rdma_req_to_abort->req.cmd->nvme_cmd.cid == cid) {
4140 			break;
4141 		}
4142 	}
4143 
4144 	if (rdma_req_to_abort == NULL) {
4145 		spdk_nvmf_request_complete(req);
4146 		return;
4147 	}
4148 
4149 	req->req_to_abort = &rdma_req_to_abort->req;
4150 	req->timeout_tsc = spdk_get_ticks() +
4151 			   transport->opts.abort_timeout_sec * spdk_get_ticks_hz();
4152 	req->poller = NULL;
4153 
4154 	_nvmf_rdma_qpair_abort_request(req);
4155 }
4156 
4157 static int
4158 nvmf_rdma_poll_group_get_stat(struct spdk_nvmf_tgt *tgt,
4159 			      struct spdk_nvmf_transport_poll_group_stat **stat)
4160 {
4161 	struct spdk_io_channel *ch;
4162 	struct spdk_nvmf_poll_group *group;
4163 	struct spdk_nvmf_transport_poll_group *tgroup;
4164 	struct spdk_nvmf_rdma_poll_group *rgroup;
4165 	struct spdk_nvmf_rdma_poller *rpoller;
4166 	struct spdk_nvmf_rdma_device_stat *device_stat;
4167 	uint64_t num_devices = 0;
4168 
4169 	if (tgt == NULL || stat == NULL) {
4170 		return -EINVAL;
4171 	}
4172 
4173 	ch = spdk_get_io_channel(tgt);
4174 	group = spdk_io_channel_get_ctx(ch);;
4175 	spdk_put_io_channel(ch);
4176 	TAILQ_FOREACH(tgroup, &group->tgroups, link) {
4177 		if (SPDK_NVME_TRANSPORT_RDMA == tgroup->transport->ops->type) {
4178 			*stat = calloc(1, sizeof(struct spdk_nvmf_transport_poll_group_stat));
4179 			if (!*stat) {
4180 				SPDK_ERRLOG("Failed to allocate memory for NVMf RDMA statistics\n");
4181 				return -ENOMEM;
4182 			}
4183 			(*stat)->trtype = SPDK_NVME_TRANSPORT_RDMA;
4184 
4185 			rgroup = SPDK_CONTAINEROF(tgroup, struct spdk_nvmf_rdma_poll_group, group);
4186 			/* Count devices to allocate enough memory */
4187 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4188 				++num_devices;
4189 			}
4190 			(*stat)->rdma.devices = calloc(num_devices, sizeof(struct spdk_nvmf_rdma_device_stat));
4191 			if (!(*stat)->rdma.devices) {
4192 				SPDK_ERRLOG("Failed to allocate NVMf RDMA devices statistics\n");
4193 				free(*stat);
4194 				return -ENOMEM;
4195 			}
4196 
4197 			(*stat)->rdma.pending_data_buffer = rgroup->stat.pending_data_buffer;
4198 			(*stat)->rdma.num_devices = num_devices;
4199 			num_devices = 0;
4200 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4201 				device_stat = &(*stat)->rdma.devices[num_devices++];
4202 				device_stat->name = ibv_get_device_name(rpoller->device->context->device);
4203 				device_stat->polls = rpoller->stat.polls;
4204 				device_stat->completions = rpoller->stat.completions;
4205 				device_stat->requests = rpoller->stat.requests;
4206 				device_stat->request_latency = rpoller->stat.request_latency;
4207 				device_stat->pending_free_request = rpoller->stat.pending_free_request;
4208 				device_stat->pending_rdma_read = rpoller->stat.pending_rdma_read;
4209 				device_stat->pending_rdma_write = rpoller->stat.pending_rdma_write;
4210 			}
4211 			return 0;
4212 		}
4213 	}
4214 	return -ENOENT;
4215 }
4216 
4217 static void
4218 nvmf_rdma_poll_group_free_stat(struct spdk_nvmf_transport_poll_group_stat *stat)
4219 {
4220 	if (stat) {
4221 		free(stat->rdma.devices);
4222 	}
4223 	free(stat);
4224 }
4225 
4226 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
4227 	.name = "RDMA",
4228 	.type = SPDK_NVME_TRANSPORT_RDMA,
4229 	.opts_init = nvmf_rdma_opts_init,
4230 	.create = nvmf_rdma_create,
4231 	.destroy = nvmf_rdma_destroy,
4232 
4233 	.listen = nvmf_rdma_listen,
4234 	.stop_listen = nvmf_rdma_stop_listen,
4235 	.accept = nvmf_rdma_accept,
4236 	.cdata_init = nvmf_rdma_cdata_init,
4237 
4238 	.listener_discover = nvmf_rdma_discover,
4239 
4240 	.poll_group_create = nvmf_rdma_poll_group_create,
4241 	.get_optimal_poll_group = nvmf_rdma_get_optimal_poll_group,
4242 	.poll_group_destroy = nvmf_rdma_poll_group_destroy,
4243 	.poll_group_add = nvmf_rdma_poll_group_add,
4244 	.poll_group_remove = nvmf_rdma_poll_group_remove,
4245 	.poll_group_poll = nvmf_rdma_poll_group_poll,
4246 
4247 	.req_free = nvmf_rdma_request_free,
4248 	.req_complete = nvmf_rdma_request_complete,
4249 
4250 	.qpair_fini = nvmf_rdma_close_qpair,
4251 	.qpair_get_peer_trid = nvmf_rdma_qpair_get_peer_trid,
4252 	.qpair_get_local_trid = nvmf_rdma_qpair_get_local_trid,
4253 	.qpair_get_listen_trid = nvmf_rdma_qpair_get_listen_trid,
4254 	.qpair_abort_request = nvmf_rdma_qpair_abort_request,
4255 
4256 	.poll_group_get_stat = nvmf_rdma_poll_group_get_stat,
4257 	.poll_group_free_stat = nvmf_rdma_poll_group_free_stat,
4258 };
4259 
4260 SPDK_NVMF_TRANSPORT_REGISTER(rdma, &spdk_nvmf_transport_rdma);
4261 SPDK_LOG_REGISTER_COMPONENT("rdma", SPDK_LOG_RDMA)
4262