xref: /spdk/lib/nvmf/rdma.c (revision 90ba272cee71afa2cb11f6de7581b601d2e44cfe)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (C) 2016 Intel Corporation. All rights reserved.
3  *   Copyright (c) 2019-2021 Mellanox Technologies LTD. All rights reserved.
4  *   Copyright (c) 2021-2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
5  */
6 
7 #include "spdk/stdinc.h"
8 
9 #include "spdk/config.h"
10 #include "spdk/thread.h"
11 #include "spdk/likely.h"
12 #include "spdk/nvmf_transport.h"
13 #include "spdk/string.h"
14 #include "spdk/trace.h"
15 #include "spdk/tree.h"
16 #include "spdk/util.h"
17 
18 #include "spdk_internal/assert.h"
19 #include "spdk/log.h"
20 #include "spdk_internal/rdma.h"
21 
22 #include "nvmf_internal.h"
23 #include "transport.h"
24 
25 #include "spdk_internal/trace_defs.h"
26 
27 struct spdk_nvme_rdma_hooks g_nvmf_hooks = {};
28 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma;
29 
30 /*
31  RDMA Connection Resource Defaults
32  */
33 #define NVMF_DEFAULT_MSDBD		16
34 #define NVMF_DEFAULT_TX_SGE		SPDK_NVMF_MAX_SGL_ENTRIES
35 #define NVMF_DEFAULT_RSP_SGE		1
36 #define NVMF_DEFAULT_RX_SGE		2
37 
38 #define NVMF_RDMA_MAX_EVENTS_PER_POLL	32
39 
40 SPDK_STATIC_ASSERT(NVMF_DEFAULT_MSDBD <= SPDK_NVMF_MAX_SGL_ENTRIES,
41 		   "MSDBD must not exceed SPDK_NVMF_MAX_SGL_ENTRIES");
42 
43 /* The RDMA completion queue size */
44 #define DEFAULT_NVMF_RDMA_CQ_SIZE	4096
45 #define MAX_WR_PER_QP(queue_depth)	(queue_depth * 3 + 2)
46 
47 enum spdk_nvmf_rdma_request_state {
48 	/* The request is not currently in use */
49 	RDMA_REQUEST_STATE_FREE = 0,
50 
51 	/* Initial state when request first received */
52 	RDMA_REQUEST_STATE_NEW,
53 
54 	/* The request is queued until a data buffer is available. */
55 	RDMA_REQUEST_STATE_NEED_BUFFER,
56 
57 	/* The request is waiting on RDMA queue depth availability
58 	 * to transfer data from the host to the controller.
59 	 */
60 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
61 
62 	/* The request is currently transferring data from the host to the controller. */
63 	RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
64 
65 	/* The request is ready to execute at the block device */
66 	RDMA_REQUEST_STATE_READY_TO_EXECUTE,
67 
68 	/* The request is currently executing at the block device */
69 	RDMA_REQUEST_STATE_EXECUTING,
70 
71 	/* The request finished executing at the block device */
72 	RDMA_REQUEST_STATE_EXECUTED,
73 
74 	/* The request is waiting on RDMA queue depth availability
75 	 * to transfer data from the controller to the host.
76 	 */
77 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
78 
79 	/* The request is waiting on RDMA queue depth availability
80 	 * to send response to the host.
81 	 */
82 	RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING,
83 
84 	/* The request is ready to send a completion */
85 	RDMA_REQUEST_STATE_READY_TO_COMPLETE,
86 
87 	/* The request is currently transferring data from the controller to the host. */
88 	RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
89 
90 	/* The request currently has an outstanding completion without an
91 	 * associated data transfer.
92 	 */
93 	RDMA_REQUEST_STATE_COMPLETING,
94 
95 	/* The request completed and can be marked free. */
96 	RDMA_REQUEST_STATE_COMPLETED,
97 
98 	/* Terminator */
99 	RDMA_REQUEST_NUM_STATES,
100 };
101 
102 SPDK_TRACE_REGISTER_FN(nvmf_trace, "nvmf_rdma", TRACE_GROUP_NVMF_RDMA)
103 {
104 	spdk_trace_register_object(OBJECT_NVMF_RDMA_IO, 'r');
105 	spdk_trace_register_description("RDMA_REQ_NEW", TRACE_RDMA_REQUEST_STATE_NEW,
106 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 1,
107 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
108 	spdk_trace_register_description("RDMA_REQ_NEED_BUFFER", TRACE_RDMA_REQUEST_STATE_NEED_BUFFER,
109 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
110 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
111 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_C2H",
112 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
113 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
114 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
115 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_H2C",
116 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
117 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
118 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
119 	spdk_trace_register_description("RDMA_REQ_TX_H2C",
120 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
121 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
122 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
123 	spdk_trace_register_description("RDMA_REQ_RDY_TO_EXECUTE",
124 					TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE,
125 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
126 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
127 	spdk_trace_register_description("RDMA_REQ_EXECUTING",
128 					TRACE_RDMA_REQUEST_STATE_EXECUTING,
129 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
130 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
131 	spdk_trace_register_description("RDMA_REQ_EXECUTED",
132 					TRACE_RDMA_REQUEST_STATE_EXECUTED,
133 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
134 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
135 	spdk_trace_register_description("RDMA_REQ_RDY2COMPL_PEND",
136 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING,
137 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
138 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
139 	spdk_trace_register_description("RDMA_REQ_RDY_TO_COMPL",
140 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE,
141 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
142 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
143 	spdk_trace_register_description("RDMA_REQ_COMPLETING_C2H",
144 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
145 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
146 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
147 	spdk_trace_register_description("RDMA_REQ_COMPLETING",
148 					TRACE_RDMA_REQUEST_STATE_COMPLETING,
149 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
150 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
151 	spdk_trace_register_description("RDMA_REQ_COMPLETED",
152 					TRACE_RDMA_REQUEST_STATE_COMPLETED,
153 					OWNER_TYPE_NONE, OBJECT_NVMF_RDMA_IO, 0,
154 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
155 
156 	spdk_trace_register_description("RDMA_QP_CREATE", TRACE_RDMA_QP_CREATE,
157 					OWNER_TYPE_NONE, OBJECT_NONE, 0,
158 					SPDK_TRACE_ARG_TYPE_INT, "");
159 	spdk_trace_register_description("RDMA_IBV_ASYNC_EVENT", TRACE_RDMA_IBV_ASYNC_EVENT,
160 					OWNER_TYPE_NONE, OBJECT_NONE, 0,
161 					SPDK_TRACE_ARG_TYPE_INT, "type");
162 	spdk_trace_register_description("RDMA_CM_ASYNC_EVENT", TRACE_RDMA_CM_ASYNC_EVENT,
163 					OWNER_TYPE_NONE, OBJECT_NONE, 0,
164 					SPDK_TRACE_ARG_TYPE_INT, "type");
165 	spdk_trace_register_description("RDMA_QP_DISCONNECT", TRACE_RDMA_QP_DISCONNECT,
166 					OWNER_TYPE_NONE, OBJECT_NONE, 0,
167 					SPDK_TRACE_ARG_TYPE_INT, "");
168 	spdk_trace_register_description("RDMA_QP_DESTROY", TRACE_RDMA_QP_DESTROY,
169 					OWNER_TYPE_NONE, OBJECT_NONE, 0,
170 					SPDK_TRACE_ARG_TYPE_INT, "");
171 }
172 
173 enum spdk_nvmf_rdma_wr_type {
174 	RDMA_WR_TYPE_RECV,
175 	RDMA_WR_TYPE_SEND,
176 	RDMA_WR_TYPE_DATA,
177 };
178 
179 struct spdk_nvmf_rdma_wr {
180 	/* Uses enum spdk_nvmf_rdma_wr_type */
181 	uint8_t type;
182 };
183 
184 /* This structure holds commands as they are received off the wire.
185  * It must be dynamically paired with a full request object
186  * (spdk_nvmf_rdma_request) to service a request. It is separate
187  * from the request because RDMA does not appear to order
188  * completions, so occasionally we'll get a new incoming
189  * command when there aren't any free request objects.
190  */
191 struct spdk_nvmf_rdma_recv {
192 	struct ibv_recv_wr			wr;
193 	struct ibv_sge				sgl[NVMF_DEFAULT_RX_SGE];
194 
195 	struct spdk_nvmf_rdma_qpair		*qpair;
196 
197 	/* In-capsule data buffer */
198 	uint8_t					*buf;
199 
200 	struct spdk_nvmf_rdma_wr		rdma_wr;
201 	uint64_t				receive_tsc;
202 
203 	STAILQ_ENTRY(spdk_nvmf_rdma_recv)	link;
204 };
205 
206 struct spdk_nvmf_rdma_request_data {
207 	struct ibv_send_wr		wr;
208 	struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
209 };
210 
211 struct spdk_nvmf_rdma_request {
212 	struct spdk_nvmf_request		req;
213 
214 	bool					fused_failed;
215 
216 	struct spdk_nvmf_rdma_wr		data_wr;
217 	struct spdk_nvmf_rdma_wr		rsp_wr;
218 
219 	/* Uses enum spdk_nvmf_rdma_request_state */
220 	uint8_t					state;
221 
222 	/* Data offset in req.iov */
223 	uint32_t				offset;
224 
225 	struct spdk_nvmf_rdma_recv		*recv;
226 
227 	struct {
228 		struct	ibv_send_wr		wr;
229 		struct	ibv_sge			sgl[NVMF_DEFAULT_RSP_SGE];
230 	} rsp;
231 
232 	uint16_t				iovpos;
233 	uint16_t				num_outstanding_data_wr;
234 	/* Used to split Write IO with multi SGL payload */
235 	uint16_t				num_remaining_data_wr;
236 	uint64_t				receive_tsc;
237 	struct spdk_nvmf_rdma_request		*fused_pair;
238 	STAILQ_ENTRY(spdk_nvmf_rdma_request)	state_link;
239 	struct ibv_send_wr			*remaining_tranfer_in_wrs;
240 	struct ibv_send_wr			*transfer_wr;
241 	struct spdk_nvmf_rdma_request_data	data;
242 };
243 
244 struct spdk_nvmf_rdma_resource_opts {
245 	struct spdk_nvmf_rdma_qpair	*qpair;
246 	/* qp points either to an ibv_qp object or an ibv_srq object depending on the value of shared. */
247 	void				*qp;
248 	struct spdk_rdma_mem_map	*map;
249 	uint32_t			max_queue_depth;
250 	uint32_t			in_capsule_data_size;
251 	bool				shared;
252 };
253 
254 struct spdk_nvmf_rdma_resources {
255 	/* Array of size "max_queue_depth" containing RDMA requests. */
256 	struct spdk_nvmf_rdma_request		*reqs;
257 
258 	/* Array of size "max_queue_depth" containing RDMA recvs. */
259 	struct spdk_nvmf_rdma_recv		*recvs;
260 
261 	/* Array of size "max_queue_depth" containing 64 byte capsules
262 	 * used for receive.
263 	 */
264 	union nvmf_h2c_msg			*cmds;
265 
266 	/* Array of size "max_queue_depth" containing 16 byte completions
267 	 * to be sent back to the user.
268 	 */
269 	union nvmf_c2h_msg			*cpls;
270 
271 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
272 	 * buffers to be used for in capsule data.
273 	 */
274 	void					*bufs;
275 
276 	/* Receives that are waiting for a request object */
277 	STAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
278 
279 	/* Queue to track free requests */
280 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	free_queue;
281 };
282 
283 typedef void (*spdk_nvmf_rdma_qpair_ibv_event)(struct spdk_nvmf_rdma_qpair *rqpair);
284 
285 typedef void (*spdk_poller_destroy_cb)(void *ctx);
286 
287 struct spdk_nvmf_rdma_ibv_event_ctx {
288 	struct spdk_nvmf_rdma_qpair			*rqpair;
289 	spdk_nvmf_rdma_qpair_ibv_event			cb_fn;
290 	/* Link to other ibv events associated with this qpair */
291 	STAILQ_ENTRY(spdk_nvmf_rdma_ibv_event_ctx)	link;
292 };
293 
294 struct spdk_nvmf_rdma_qpair {
295 	struct spdk_nvmf_qpair			qpair;
296 
297 	struct spdk_nvmf_rdma_device		*device;
298 	struct spdk_nvmf_rdma_poller		*poller;
299 
300 	struct spdk_rdma_qp			*rdma_qp;
301 	struct rdma_cm_id			*cm_id;
302 	struct spdk_rdma_srq			*srq;
303 	struct rdma_cm_id			*listen_id;
304 
305 	/* Cache the QP number to improve QP search by RB tree. */
306 	uint32_t				qp_num;
307 
308 	/* The maximum number of I/O outstanding on this connection at one time */
309 	uint16_t				max_queue_depth;
310 
311 	/* The maximum number of active RDMA READ and ATOMIC operations at one time */
312 	uint16_t				max_read_depth;
313 
314 	/* The maximum number of RDMA SEND operations at one time */
315 	uint32_t				max_send_depth;
316 
317 	/* The current number of outstanding WRs from this qpair's
318 	 * recv queue. Should not exceed device->attr.max_queue_depth.
319 	 */
320 	uint16_t				current_recv_depth;
321 
322 	/* The current number of active RDMA READ operations */
323 	uint16_t				current_read_depth;
324 
325 	/* The current number of posted WRs from this qpair's
326 	 * send queue. Should not exceed max_send_depth.
327 	 */
328 	uint32_t				current_send_depth;
329 
330 	/* The maximum number of SGEs per WR on the send queue */
331 	uint32_t				max_send_sge;
332 
333 	/* The maximum number of SGEs per WR on the recv queue */
334 	uint32_t				max_recv_sge;
335 
336 	struct spdk_nvmf_rdma_resources		*resources;
337 
338 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_read_queue;
339 
340 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_write_queue;
341 
342 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_send_queue;
343 
344 	/* Number of requests not in the free state */
345 	uint32_t				qd;
346 
347 	bool					ibv_in_error_state;
348 
349 	RB_ENTRY(spdk_nvmf_rdma_qpair)		node;
350 
351 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	recv_link;
352 
353 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	send_link;
354 
355 	/* Points to the a request that has fuse bits set to
356 	 * SPDK_NVME_CMD_FUSE_FIRST, when the qpair is waiting
357 	 * for the request that has SPDK_NVME_CMD_FUSE_SECOND.
358 	 */
359 	struct spdk_nvmf_rdma_request		*fused_first;
360 
361 	/*
362 	 * io_channel which is used to destroy qpair when it is removed from poll group
363 	 */
364 	struct spdk_io_channel		*destruct_channel;
365 
366 	/* List of ibv async events */
367 	STAILQ_HEAD(, spdk_nvmf_rdma_ibv_event_ctx)	ibv_events;
368 
369 	/* Lets us know that we have received the last_wqe event. */
370 	bool					last_wqe_reached;
371 
372 	/* Indicate that nvmf_rdma_close_qpair is called */
373 	bool					to_close;
374 };
375 
376 struct spdk_nvmf_rdma_poller_stat {
377 	uint64_t				completions;
378 	uint64_t				polls;
379 	uint64_t				idle_polls;
380 	uint64_t				requests;
381 	uint64_t				request_latency;
382 	uint64_t				pending_free_request;
383 	uint64_t				pending_rdma_read;
384 	uint64_t				pending_rdma_write;
385 	uint64_t				pending_rdma_send;
386 	struct spdk_rdma_qp_stats		qp_stats;
387 };
388 
389 struct spdk_nvmf_rdma_poller {
390 	struct spdk_nvmf_rdma_device		*device;
391 	struct spdk_nvmf_rdma_poll_group	*group;
392 
393 	int					num_cqe;
394 	int					required_num_wr;
395 	struct ibv_cq				*cq;
396 
397 	/* The maximum number of I/O outstanding on the shared receive queue at one time */
398 	uint16_t				max_srq_depth;
399 	bool					need_destroy;
400 
401 	/* Shared receive queue */
402 	struct spdk_rdma_srq			*srq;
403 
404 	struct spdk_nvmf_rdma_resources		*resources;
405 	struct spdk_nvmf_rdma_poller_stat	stat;
406 
407 	spdk_poller_destroy_cb			destroy_cb;
408 	void					*destroy_cb_ctx;
409 
410 	RB_HEAD(qpairs_tree, spdk_nvmf_rdma_qpair) qpairs;
411 
412 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_recv;
413 
414 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_send;
415 
416 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
417 };
418 
419 struct spdk_nvmf_rdma_poll_group_stat {
420 	uint64_t				pending_data_buffer;
421 };
422 
423 struct spdk_nvmf_rdma_poll_group {
424 	struct spdk_nvmf_transport_poll_group		group;
425 	struct spdk_nvmf_rdma_poll_group_stat		stat;
426 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)		pollers;
427 	TAILQ_ENTRY(spdk_nvmf_rdma_poll_group)		link;
428 };
429 
430 struct spdk_nvmf_rdma_conn_sched {
431 	struct spdk_nvmf_rdma_poll_group *next_admin_pg;
432 	struct spdk_nvmf_rdma_poll_group *next_io_pg;
433 };
434 
435 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
436 struct spdk_nvmf_rdma_device {
437 	struct ibv_device_attr			attr;
438 	struct ibv_context			*context;
439 
440 	struct spdk_rdma_mem_map		*map;
441 	struct ibv_pd				*pd;
442 
443 	int					num_srq;
444 	bool					need_destroy;
445 	bool					ready_to_destroy;
446 	bool					is_ready;
447 
448 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
449 };
450 
451 struct spdk_nvmf_rdma_port {
452 	const struct spdk_nvme_transport_id	*trid;
453 	struct rdma_cm_id			*id;
454 	struct spdk_nvmf_rdma_device		*device;
455 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
456 };
457 
458 struct rdma_transport_opts {
459 	int		num_cqe;
460 	uint32_t	max_srq_depth;
461 	bool		no_srq;
462 	bool		no_wr_batching;
463 	int		acceptor_backlog;
464 };
465 
466 struct spdk_nvmf_rdma_transport {
467 	struct spdk_nvmf_transport	transport;
468 	struct rdma_transport_opts	rdma_opts;
469 
470 	struct spdk_nvmf_rdma_conn_sched conn_sched;
471 
472 	struct rdma_event_channel	*event_channel;
473 
474 	struct spdk_mempool		*data_wr_pool;
475 
476 	struct spdk_poller		*accept_poller;
477 
478 	/* fields used to poll RDMA/IB events */
479 	nfds_t			npoll_fds;
480 	struct pollfd		*poll_fds;
481 
482 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
483 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
484 	TAILQ_HEAD(, spdk_nvmf_rdma_poll_group)	poll_groups;
485 
486 	/* ports that are removed unexpectedly and need retry listen */
487 	TAILQ_HEAD(, spdk_nvmf_rdma_port)		retry_ports;
488 };
489 
490 struct poller_manage_ctx {
491 	struct spdk_nvmf_rdma_transport		*rtransport;
492 	struct spdk_nvmf_rdma_poll_group	*rgroup;
493 	struct spdk_nvmf_rdma_poller		*rpoller;
494 	struct spdk_nvmf_rdma_device		*device;
495 
496 	struct spdk_thread			*thread;
497 	volatile int				*inflight_op_counter;
498 };
499 
500 static const struct spdk_json_object_decoder rdma_transport_opts_decoder[] = {
501 	{
502 		"num_cqe", offsetof(struct rdma_transport_opts, num_cqe),
503 		spdk_json_decode_int32, true
504 	},
505 	{
506 		"max_srq_depth", offsetof(struct rdma_transport_opts, max_srq_depth),
507 		spdk_json_decode_uint32, true
508 	},
509 	{
510 		"no_srq", offsetof(struct rdma_transport_opts, no_srq),
511 		spdk_json_decode_bool, true
512 	},
513 	{
514 		"no_wr_batching", offsetof(struct rdma_transport_opts, no_wr_batching),
515 		spdk_json_decode_bool, true
516 	},
517 	{
518 		"acceptor_backlog", offsetof(struct rdma_transport_opts, acceptor_backlog),
519 		spdk_json_decode_int32, true
520 	},
521 };
522 
523 static int
524 nvmf_rdma_qpair_compare(struct spdk_nvmf_rdma_qpair *rqpair1, struct spdk_nvmf_rdma_qpair *rqpair2)
525 {
526 	return rqpair1->qp_num < rqpair2->qp_num ? -1 : rqpair1->qp_num > rqpair2->qp_num;
527 }
528 
529 RB_GENERATE_STATIC(qpairs_tree, spdk_nvmf_rdma_qpair, node, nvmf_rdma_qpair_compare);
530 
531 static bool nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
532 				      struct spdk_nvmf_rdma_request *rdma_req);
533 
534 static void _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
535 				 struct spdk_nvmf_rdma_poller *rpoller);
536 
537 static void _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
538 				 struct spdk_nvmf_rdma_poller *rpoller);
539 
540 static void _nvmf_rdma_remove_destroyed_device(void *c);
541 
542 static inline enum spdk_nvme_media_error_status_code
543 nvmf_rdma_dif_error_to_compl_status(uint8_t err_type) {
544 	enum spdk_nvme_media_error_status_code result;
545 	switch (err_type)
546 	{
547 	case SPDK_DIF_REFTAG_ERROR:
548 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
549 		break;
550 	case SPDK_DIF_APPTAG_ERROR:
551 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
552 		break;
553 	case SPDK_DIF_GUARD_ERROR:
554 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
555 		break;
556 	default:
557 		SPDK_UNREACHABLE();
558 	}
559 
560 	return result;
561 }
562 
563 /*
564  * Return data_wrs to pool starting from \b data_wr
565  * Request's own response and data WR are excluded
566  */
567 static void
568 _nvmf_rdma_request_free_data(struct spdk_nvmf_rdma_request *rdma_req,
569 			     struct ibv_send_wr *data_wr,
570 			     struct spdk_mempool *pool)
571 {
572 	struct spdk_nvmf_rdma_request_data	*work_requests[SPDK_NVMF_MAX_SGL_ENTRIES];
573 	struct spdk_nvmf_rdma_request_data	*nvmf_data;
574 	struct ibv_send_wr			*next_send_wr;
575 	uint64_t				req_wrid = (uint64_t)&rdma_req->data_wr;
576 	uint32_t				num_wrs = 0;
577 
578 	while (data_wr && data_wr->wr_id == req_wrid) {
579 		nvmf_data = SPDK_CONTAINEROF(data_wr, struct spdk_nvmf_rdma_request_data, wr);
580 		memset(nvmf_data->sgl, 0, sizeof(data_wr->sg_list[0]) * data_wr->num_sge);
581 		data_wr->num_sge = 0;
582 		next_send_wr = data_wr->next;
583 		if (data_wr != &rdma_req->data.wr) {
584 			data_wr->next = NULL;
585 			assert(num_wrs < SPDK_NVMF_MAX_SGL_ENTRIES);
586 			work_requests[num_wrs] = nvmf_data;
587 			num_wrs++;
588 		}
589 		data_wr = (!next_send_wr || next_send_wr == &rdma_req->rsp.wr) ? NULL : next_send_wr;
590 	}
591 
592 	if (num_wrs) {
593 		spdk_mempool_put_bulk(pool, (void **) work_requests, num_wrs);
594 	}
595 }
596 
597 static void
598 nvmf_rdma_request_free_data(struct spdk_nvmf_rdma_request *rdma_req,
599 			    struct spdk_nvmf_rdma_transport *rtransport)
600 {
601 	rdma_req->num_outstanding_data_wr = 0;
602 
603 	_nvmf_rdma_request_free_data(rdma_req, rdma_req->transfer_wr, rtransport->data_wr_pool);
604 
605 	if (rdma_req->remaining_tranfer_in_wrs) {
606 		_nvmf_rdma_request_free_data(rdma_req, rdma_req->remaining_tranfer_in_wrs,
607 					     rtransport->data_wr_pool);
608 		rdma_req->remaining_tranfer_in_wrs = NULL;
609 	}
610 
611 	rdma_req->data.wr.next = NULL;
612 	rdma_req->rsp.wr.next = NULL;
613 }
614 
615 static void
616 nvmf_rdma_dump_request(struct spdk_nvmf_rdma_request *req)
617 {
618 	SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", req->req.data_from_pool);
619 	if (req->req.cmd) {
620 		SPDK_ERRLOG("\t\tRequest opcode: %d\n", req->req.cmd->nvmf_cmd.opcode);
621 	}
622 	if (req->recv) {
623 		SPDK_ERRLOG("\t\tRequest recv wr_id%lu\n", req->recv->wr.wr_id);
624 	}
625 }
626 
627 static void
628 nvmf_rdma_dump_qpair_contents(struct spdk_nvmf_rdma_qpair *rqpair)
629 {
630 	int i;
631 
632 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", rqpair->qpair.qid);
633 	for (i = 0; i < rqpair->max_queue_depth; i++) {
634 		if (rqpair->resources->reqs[i].state != RDMA_REQUEST_STATE_FREE) {
635 			nvmf_rdma_dump_request(&rqpair->resources->reqs[i]);
636 		}
637 	}
638 }
639 
640 static void
641 nvmf_rdma_resources_destroy(struct spdk_nvmf_rdma_resources *resources)
642 {
643 	spdk_free(resources->cmds);
644 	spdk_free(resources->cpls);
645 	spdk_free(resources->bufs);
646 	spdk_free(resources->reqs);
647 	spdk_free(resources->recvs);
648 	free(resources);
649 }
650 
651 
652 static struct spdk_nvmf_rdma_resources *
653 nvmf_rdma_resources_create(struct spdk_nvmf_rdma_resource_opts *opts)
654 {
655 	struct spdk_nvmf_rdma_resources		*resources;
656 	struct spdk_nvmf_rdma_request		*rdma_req;
657 	struct spdk_nvmf_rdma_recv		*rdma_recv;
658 	struct spdk_rdma_qp			*qp = NULL;
659 	struct spdk_rdma_srq			*srq = NULL;
660 	struct ibv_recv_wr			*bad_wr = NULL;
661 	struct spdk_rdma_memory_translation	translation;
662 	uint32_t				i;
663 	int					rc = 0;
664 
665 	resources = calloc(1, sizeof(struct spdk_nvmf_rdma_resources));
666 	if (!resources) {
667 		SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
668 		return NULL;
669 	}
670 
671 	resources->reqs = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->reqs),
672 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
673 	resources->recvs = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->recvs),
674 					0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
675 	resources->cmds = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cmds),
676 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
677 	resources->cpls = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cpls),
678 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
679 
680 	if (opts->in_capsule_data_size > 0) {
681 		resources->bufs = spdk_zmalloc(opts->max_queue_depth * opts->in_capsule_data_size,
682 					       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY,
683 					       SPDK_MALLOC_DMA);
684 	}
685 
686 	if (!resources->reqs || !resources->recvs || !resources->cmds ||
687 	    !resources->cpls || (opts->in_capsule_data_size && !resources->bufs)) {
688 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
689 		goto cleanup;
690 	}
691 
692 	SPDK_DEBUGLOG(rdma, "Command Array: %p Length: %lx\n",
693 		      resources->cmds, opts->max_queue_depth * sizeof(*resources->cmds));
694 	SPDK_DEBUGLOG(rdma, "Completion Array: %p Length: %lx\n",
695 		      resources->cpls, opts->max_queue_depth * sizeof(*resources->cpls));
696 	if (resources->bufs) {
697 		SPDK_DEBUGLOG(rdma, "In Capsule Data Array: %p Length: %x\n",
698 			      resources->bufs, opts->max_queue_depth *
699 			      opts->in_capsule_data_size);
700 	}
701 
702 	/* Initialize queues */
703 	STAILQ_INIT(&resources->incoming_queue);
704 	STAILQ_INIT(&resources->free_queue);
705 
706 	if (opts->shared) {
707 		srq = (struct spdk_rdma_srq *)opts->qp;
708 	} else {
709 		qp = (struct spdk_rdma_qp *)opts->qp;
710 	}
711 
712 	for (i = 0; i < opts->max_queue_depth; i++) {
713 		rdma_recv = &resources->recvs[i];
714 		rdma_recv->qpair = opts->qpair;
715 
716 		/* Set up memory to receive commands */
717 		if (resources->bufs) {
718 			rdma_recv->buf = (void *)((uintptr_t)resources->bufs + (i *
719 						  opts->in_capsule_data_size));
720 		}
721 
722 		rdma_recv->rdma_wr.type = RDMA_WR_TYPE_RECV;
723 
724 		rdma_recv->sgl[0].addr = (uintptr_t)&resources->cmds[i];
725 		rdma_recv->sgl[0].length = sizeof(resources->cmds[i]);
726 		rc = spdk_rdma_get_translation(opts->map, &resources->cmds[i], sizeof(resources->cmds[i]),
727 					       &translation);
728 		if (rc) {
729 			goto cleanup;
730 		}
731 		rdma_recv->sgl[0].lkey = spdk_rdma_memory_translation_get_lkey(&translation);
732 		rdma_recv->wr.num_sge = 1;
733 
734 		if (rdma_recv->buf) {
735 			rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
736 			rdma_recv->sgl[1].length = opts->in_capsule_data_size;
737 			rc = spdk_rdma_get_translation(opts->map, rdma_recv->buf, opts->in_capsule_data_size, &translation);
738 			if (rc) {
739 				goto cleanup;
740 			}
741 			rdma_recv->sgl[1].lkey = spdk_rdma_memory_translation_get_lkey(&translation);
742 			rdma_recv->wr.num_sge++;
743 		}
744 
745 		rdma_recv->wr.wr_id = (uintptr_t)&rdma_recv->rdma_wr;
746 		rdma_recv->wr.sg_list = rdma_recv->sgl;
747 		if (srq) {
748 			spdk_rdma_srq_queue_recv_wrs(srq, &rdma_recv->wr);
749 		} else {
750 			spdk_rdma_qp_queue_recv_wrs(qp, &rdma_recv->wr);
751 		}
752 	}
753 
754 	for (i = 0; i < opts->max_queue_depth; i++) {
755 		rdma_req = &resources->reqs[i];
756 
757 		if (opts->qpair != NULL) {
758 			rdma_req->req.qpair = &opts->qpair->qpair;
759 		} else {
760 			rdma_req->req.qpair = NULL;
761 		}
762 		rdma_req->req.cmd = NULL;
763 		rdma_req->req.iovcnt = 0;
764 		rdma_req->req.stripped_data = NULL;
765 
766 		/* Set up memory to send responses */
767 		rdma_req->req.rsp = &resources->cpls[i];
768 
769 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&resources->cpls[i];
770 		rdma_req->rsp.sgl[0].length = sizeof(resources->cpls[i]);
771 		rc = spdk_rdma_get_translation(opts->map, &resources->cpls[i], sizeof(resources->cpls[i]),
772 					       &translation);
773 		if (rc) {
774 			goto cleanup;
775 		}
776 		rdma_req->rsp.sgl[0].lkey = spdk_rdma_memory_translation_get_lkey(&translation);
777 
778 		rdma_req->rsp_wr.type = RDMA_WR_TYPE_SEND;
779 		rdma_req->rsp.wr.wr_id = (uintptr_t)&rdma_req->rsp_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_wr.type = RDMA_WR_TYPE_DATA;
788 		rdma_req->data.wr.wr_id = (uintptr_t)&rdma_req->data_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 	if (srq) {
800 		rc = spdk_rdma_srq_flush_recv_wrs(srq, &bad_wr);
801 	} else {
802 		rc = spdk_rdma_qp_flush_recv_wrs(qp, &bad_wr);
803 	}
804 
805 	if (rc) {
806 		goto cleanup;
807 	}
808 
809 	return resources;
810 
811 cleanup:
812 	nvmf_rdma_resources_destroy(resources);
813 	return NULL;
814 }
815 
816 static void
817 nvmf_rdma_qpair_clean_ibv_events(struct spdk_nvmf_rdma_qpair *rqpair)
818 {
819 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx, *tctx;
820 	STAILQ_FOREACH_SAFE(ctx, &rqpair->ibv_events, link, tctx) {
821 		ctx->rqpair = NULL;
822 		/* Memory allocated for ctx is freed in nvmf_rdma_qpair_process_ibv_event */
823 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
824 	}
825 }
826 
827 static void nvmf_rdma_poller_destroy(struct spdk_nvmf_rdma_poller *poller);
828 
829 static void
830 nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
831 {
832 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
833 	struct ibv_recv_wr		*bad_recv_wr = NULL;
834 	int				rc;
835 
836 	spdk_trace_record(TRACE_RDMA_QP_DESTROY, 0, 0, (uintptr_t)rqpair);
837 
838 	if (rqpair->qd != 0) {
839 		struct spdk_nvmf_qpair *qpair = &rqpair->qpair;
840 		struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(qpair->transport,
841 				struct spdk_nvmf_rdma_transport, transport);
842 		struct spdk_nvmf_rdma_request *req;
843 		uint32_t i, max_req_count = 0;
844 
845 		SPDK_WARNLOG("Destroying qpair when queue depth is %d\n", rqpair->qd);
846 
847 		if (rqpair->srq == NULL) {
848 			nvmf_rdma_dump_qpair_contents(rqpair);
849 			max_req_count = rqpair->max_queue_depth;
850 		} else if (rqpair->poller && rqpair->resources) {
851 			max_req_count = rqpair->poller->max_srq_depth;
852 		}
853 
854 		SPDK_DEBUGLOG(rdma, "Release incomplete requests\n");
855 		for (i = 0; i < max_req_count; i++) {
856 			req = &rqpair->resources->reqs[i];
857 			if (req->req.qpair == qpair && req->state != RDMA_REQUEST_STATE_FREE) {
858 				/* nvmf_rdma_request_process checks qpair ibv and internal state
859 				 * and completes a request */
860 				nvmf_rdma_request_process(rtransport, req);
861 			}
862 		}
863 		assert(rqpair->qd == 0);
864 	}
865 
866 	if (rqpair->poller) {
867 		RB_REMOVE(qpairs_tree, &rqpair->poller->qpairs, rqpair);
868 
869 		if (rqpair->srq != NULL && rqpair->resources != NULL) {
870 			/* Drop all received but unprocessed commands for this queue and return them to SRQ */
871 			STAILQ_FOREACH_SAFE(rdma_recv, &rqpair->resources->incoming_queue, link, recv_tmp) {
872 				if (rqpair == rdma_recv->qpair) {
873 					STAILQ_REMOVE(&rqpair->resources->incoming_queue, rdma_recv, spdk_nvmf_rdma_recv, link);
874 					spdk_rdma_srq_queue_recv_wrs(rqpair->srq, &rdma_recv->wr);
875 					rc = spdk_rdma_srq_flush_recv_wrs(rqpair->srq, &bad_recv_wr);
876 					if (rc) {
877 						SPDK_ERRLOG("Unable to re-post rx descriptor\n");
878 					}
879 				}
880 			}
881 		}
882 	}
883 
884 	if (rqpair->cm_id) {
885 		if (rqpair->rdma_qp != NULL) {
886 			spdk_rdma_qp_destroy(rqpair->rdma_qp);
887 			rqpair->rdma_qp = NULL;
888 		}
889 
890 		if (rqpair->poller != NULL && rqpair->srq == NULL) {
891 			rqpair->poller->required_num_wr -= MAX_WR_PER_QP(rqpair->max_queue_depth);
892 		}
893 	}
894 
895 	if (rqpair->srq == NULL && rqpair->resources != NULL) {
896 		nvmf_rdma_resources_destroy(rqpair->resources);
897 	}
898 
899 	nvmf_rdma_qpair_clean_ibv_events(rqpair);
900 
901 	if (rqpair->destruct_channel) {
902 		spdk_put_io_channel(rqpair->destruct_channel);
903 		rqpair->destruct_channel = NULL;
904 	}
905 
906 	if (rqpair->poller && rqpair->poller->need_destroy && RB_EMPTY(&rqpair->poller->qpairs)) {
907 		nvmf_rdma_poller_destroy(rqpair->poller);
908 	}
909 
910 	/* destroy cm_id last so cma device will not be freed before we destroy the cq. */
911 	if (rqpair->cm_id) {
912 		rdma_destroy_id(rqpair->cm_id);
913 	}
914 
915 	free(rqpair);
916 }
917 
918 static int
919 nvmf_rdma_resize_cq(struct spdk_nvmf_rdma_qpair *rqpair, struct spdk_nvmf_rdma_device *device)
920 {
921 	struct spdk_nvmf_rdma_poller	*rpoller;
922 	int				rc, num_cqe, required_num_wr;
923 
924 	/* Enlarge CQ size dynamically */
925 	rpoller = rqpair->poller;
926 	required_num_wr = rpoller->required_num_wr + MAX_WR_PER_QP(rqpair->max_queue_depth);
927 	num_cqe = rpoller->num_cqe;
928 	if (num_cqe < required_num_wr) {
929 		num_cqe = spdk_max(num_cqe * 2, required_num_wr);
930 		num_cqe = spdk_min(num_cqe, device->attr.max_cqe);
931 	}
932 
933 	if (rpoller->num_cqe != num_cqe) {
934 		if (device->context->device->transport_type == IBV_TRANSPORT_IWARP) {
935 			SPDK_ERRLOG("iWARP doesn't support CQ resize. Current capacity %u, required %u\n"
936 				    "Using CQ of insufficient size may lead to CQ overrun\n", rpoller->num_cqe, num_cqe);
937 			return -1;
938 		}
939 		if (required_num_wr > device->attr.max_cqe) {
940 			SPDK_ERRLOG("RDMA CQE requirement (%d) exceeds device max_cqe limitation (%d)\n",
941 				    required_num_wr, device->attr.max_cqe);
942 			return -1;
943 		}
944 
945 		SPDK_DEBUGLOG(rdma, "Resize RDMA CQ from %d to %d\n", rpoller->num_cqe, num_cqe);
946 		rc = ibv_resize_cq(rpoller->cq, num_cqe);
947 		if (rc) {
948 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
949 			return -1;
950 		}
951 
952 		rpoller->num_cqe = num_cqe;
953 	}
954 
955 	rpoller->required_num_wr = required_num_wr;
956 	return 0;
957 }
958 
959 static int
960 nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
961 {
962 	struct spdk_nvmf_rdma_qpair		*rqpair;
963 	struct spdk_nvmf_rdma_transport		*rtransport;
964 	struct spdk_nvmf_transport		*transport;
965 	struct spdk_nvmf_rdma_resource_opts	opts;
966 	struct spdk_nvmf_rdma_device		*device;
967 	struct spdk_rdma_qp_init_attr		qp_init_attr = {};
968 
969 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
970 	device = rqpair->device;
971 
972 	qp_init_attr.qp_context	= rqpair;
973 	qp_init_attr.pd		= device->pd;
974 	qp_init_attr.send_cq	= rqpair->poller->cq;
975 	qp_init_attr.recv_cq	= rqpair->poller->cq;
976 
977 	if (rqpair->srq) {
978 		qp_init_attr.srq		= rqpair->srq->srq;
979 	} else {
980 		qp_init_attr.cap.max_recv_wr	= rqpair->max_queue_depth;
981 	}
982 
983 	/* SEND, READ, and WRITE operations */
984 	qp_init_attr.cap.max_send_wr	= (uint32_t)rqpair->max_queue_depth * 2;
985 	qp_init_attr.cap.max_send_sge	= spdk_min((uint32_t)device->attr.max_sge, NVMF_DEFAULT_TX_SGE);
986 	qp_init_attr.cap.max_recv_sge	= spdk_min((uint32_t)device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
987 	qp_init_attr.stats		= &rqpair->poller->stat.qp_stats;
988 
989 	if (rqpair->srq == NULL && nvmf_rdma_resize_cq(rqpair, device) < 0) {
990 		SPDK_ERRLOG("Failed to resize the completion queue. Cannot initialize qpair.\n");
991 		goto error;
992 	}
993 
994 	rqpair->rdma_qp = spdk_rdma_qp_create(rqpair->cm_id, &qp_init_attr);
995 	if (!rqpair->rdma_qp) {
996 		goto error;
997 	}
998 
999 	rqpair->qp_num = rqpair->rdma_qp->qp->qp_num;
1000 
1001 	rqpair->max_send_depth = spdk_min((uint32_t)(rqpair->max_queue_depth * 2),
1002 					  qp_init_attr.cap.max_send_wr);
1003 	rqpair->max_send_sge = spdk_min(NVMF_DEFAULT_TX_SGE, qp_init_attr.cap.max_send_sge);
1004 	rqpair->max_recv_sge = spdk_min(NVMF_DEFAULT_RX_SGE, qp_init_attr.cap.max_recv_sge);
1005 	spdk_trace_record(TRACE_RDMA_QP_CREATE, 0, 0, (uintptr_t)rqpair);
1006 	SPDK_DEBUGLOG(rdma, "New RDMA Connection: %p\n", qpair);
1007 
1008 	if (rqpair->poller->srq == NULL) {
1009 		rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
1010 		transport = &rtransport->transport;
1011 
1012 		opts.qp = rqpair->rdma_qp;
1013 		opts.map = device->map;
1014 		opts.qpair = rqpair;
1015 		opts.shared = false;
1016 		opts.max_queue_depth = rqpair->max_queue_depth;
1017 		opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
1018 
1019 		rqpair->resources = nvmf_rdma_resources_create(&opts);
1020 
1021 		if (!rqpair->resources) {
1022 			SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
1023 			rdma_destroy_qp(rqpair->cm_id);
1024 			goto error;
1025 		}
1026 	} else {
1027 		rqpair->resources = rqpair->poller->resources;
1028 	}
1029 
1030 	rqpair->current_recv_depth = 0;
1031 	STAILQ_INIT(&rqpair->pending_rdma_read_queue);
1032 	STAILQ_INIT(&rqpair->pending_rdma_write_queue);
1033 	STAILQ_INIT(&rqpair->pending_rdma_send_queue);
1034 
1035 	return 0;
1036 
1037 error:
1038 	rdma_destroy_id(rqpair->cm_id);
1039 	rqpair->cm_id = NULL;
1040 	return -1;
1041 }
1042 
1043 /* Append the given recv wr structure to the resource structs outstanding recvs list. */
1044 /* This function accepts either a single wr or the first wr in a linked list. */
1045 static void
1046 nvmf_rdma_qpair_queue_recv_wrs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *first)
1047 {
1048 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
1049 			struct spdk_nvmf_rdma_transport, transport);
1050 
1051 	if (rqpair->srq != NULL) {
1052 		spdk_rdma_srq_queue_recv_wrs(rqpair->srq, first);
1053 	} else {
1054 		if (spdk_rdma_qp_queue_recv_wrs(rqpair->rdma_qp, first)) {
1055 			STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_recv, rqpair, recv_link);
1056 		}
1057 	}
1058 
1059 	if (rtransport->rdma_opts.no_wr_batching) {
1060 		_poller_submit_recvs(rtransport, rqpair->poller);
1061 	}
1062 }
1063 
1064 static int
1065 request_transfer_in(struct spdk_nvmf_request *req)
1066 {
1067 	struct spdk_nvmf_rdma_request	*rdma_req;
1068 	struct spdk_nvmf_qpair		*qpair;
1069 	struct spdk_nvmf_rdma_qpair	*rqpair;
1070 	struct spdk_nvmf_rdma_transport *rtransport;
1071 
1072 	qpair = req->qpair;
1073 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1074 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1075 	rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
1076 				      struct spdk_nvmf_rdma_transport, transport);
1077 
1078 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
1079 	assert(rdma_req != NULL);
1080 
1081 	if (spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, rdma_req->transfer_wr)) {
1082 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1083 	}
1084 	if (rtransport->rdma_opts.no_wr_batching) {
1085 		_poller_submit_sends(rtransport, rqpair->poller);
1086 	}
1087 
1088 	assert(rqpair->current_read_depth + rdma_req->num_outstanding_data_wr <= rqpair->max_read_depth);
1089 	rqpair->current_read_depth += rdma_req->num_outstanding_data_wr;
1090 	assert(rqpair->current_send_depth + rdma_req->num_outstanding_data_wr <= rqpair->max_send_depth);
1091 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr;
1092 	return 0;
1093 }
1094 
1095 static inline int
1096 nvmf_rdma_request_reset_transfer_in(struct spdk_nvmf_rdma_request *rdma_req,
1097 				    struct spdk_nvmf_rdma_transport *rtransport)
1098 {
1099 	/* Put completed WRs back to pool and move transfer_wr pointer */
1100 	_nvmf_rdma_request_free_data(rdma_req, rdma_req->transfer_wr, rtransport->data_wr_pool);
1101 	rdma_req->transfer_wr = rdma_req->remaining_tranfer_in_wrs;
1102 	rdma_req->remaining_tranfer_in_wrs = NULL;
1103 	rdma_req->num_outstanding_data_wr = rdma_req->num_remaining_data_wr;
1104 	rdma_req->num_remaining_data_wr = 0;
1105 
1106 	return 0;
1107 }
1108 
1109 static inline int
1110 request_prepare_transfer_in_part(struct spdk_nvmf_request *req, uint32_t num_reads_available)
1111 {
1112 	struct spdk_nvmf_rdma_request	*rdma_req;
1113 	struct ibv_send_wr		*wr;
1114 	uint32_t i;
1115 
1116 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1117 
1118 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
1119 	assert(rdma_req != NULL);
1120 	assert(num_reads_available > 0);
1121 	assert(rdma_req->num_outstanding_data_wr > num_reads_available);
1122 	wr = rdma_req->transfer_wr;
1123 
1124 	for (i = 0; i < num_reads_available - 1; i++) {
1125 		wr = wr->next;
1126 	}
1127 
1128 	rdma_req->remaining_tranfer_in_wrs = wr->next;
1129 	rdma_req->num_remaining_data_wr = rdma_req->num_outstanding_data_wr - num_reads_available;
1130 	rdma_req->num_outstanding_data_wr = num_reads_available;
1131 	/* Break chain of WRs to send only part. Once this portion completes, we continue sending RDMA_READs */
1132 	wr->next = NULL;
1133 
1134 	return 0;
1135 }
1136 
1137 static int
1138 request_transfer_out(struct spdk_nvmf_request *req, int *data_posted)
1139 {
1140 	int				num_outstanding_data_wr = 0;
1141 	struct spdk_nvmf_rdma_request	*rdma_req;
1142 	struct spdk_nvmf_qpair		*qpair;
1143 	struct spdk_nvmf_rdma_qpair	*rqpair;
1144 	struct spdk_nvme_cpl		*rsp;
1145 	struct ibv_send_wr		*first = NULL;
1146 	struct spdk_nvmf_rdma_transport *rtransport;
1147 
1148 	*data_posted = 0;
1149 	qpair = req->qpair;
1150 	rsp = &req->rsp->nvme_cpl;
1151 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1152 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1153 	rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
1154 				      struct spdk_nvmf_rdma_transport, transport);
1155 
1156 	/* Advance our sq_head pointer */
1157 	if (qpair->sq_head == qpair->sq_head_max) {
1158 		qpair->sq_head = 0;
1159 	} else {
1160 		qpair->sq_head++;
1161 	}
1162 	rsp->sqhd = qpair->sq_head;
1163 
1164 	/* queue the capsule for the recv buffer */
1165 	assert(rdma_req->recv != NULL);
1166 
1167 	nvmf_rdma_qpair_queue_recv_wrs(rqpair, &rdma_req->recv->wr);
1168 
1169 	rdma_req->recv = NULL;
1170 	assert(rqpair->current_recv_depth > 0);
1171 	rqpair->current_recv_depth--;
1172 
1173 	/* Build the response which consists of optional
1174 	 * RDMA WRITEs to transfer data, plus an RDMA SEND
1175 	 * containing the response.
1176 	 */
1177 	first = &rdma_req->rsp.wr;
1178 
1179 	if (spdk_unlikely(rsp->status.sc != SPDK_NVME_SC_SUCCESS)) {
1180 		/* On failure, data was not read from the controller. So clear the
1181 		 * number of outstanding data WRs to zero.
1182 		 */
1183 		rdma_req->num_outstanding_data_wr = 0;
1184 	} else if (req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1185 		first = rdma_req->transfer_wr;
1186 		*data_posted = 1;
1187 		num_outstanding_data_wr = rdma_req->num_outstanding_data_wr;
1188 	}
1189 	if (spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, first)) {
1190 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1191 	}
1192 	if (rtransport->rdma_opts.no_wr_batching) {
1193 		_poller_submit_sends(rtransport, rqpair->poller);
1194 	}
1195 
1196 	/* +1 for the rsp wr */
1197 	assert(rqpair->current_send_depth + num_outstanding_data_wr + 1 <= rqpair->max_send_depth);
1198 	rqpair->current_send_depth += num_outstanding_data_wr + 1;
1199 
1200 	return 0;
1201 }
1202 
1203 static int
1204 nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
1205 {
1206 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
1207 	struct rdma_conn_param				ctrlr_event_data = {};
1208 	int						rc;
1209 
1210 	accept_data.recfmt = 0;
1211 	accept_data.crqsize = rqpair->max_queue_depth;
1212 
1213 	ctrlr_event_data.private_data = &accept_data;
1214 	ctrlr_event_data.private_data_len = sizeof(accept_data);
1215 	if (id->ps == RDMA_PS_TCP) {
1216 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
1217 		ctrlr_event_data.initiator_depth = rqpair->max_read_depth;
1218 	}
1219 
1220 	/* Configure infinite retries for the initiator side qpair.
1221 	 * We need to pass this value to the initiator to prevent the
1222 	 * initiator side NIC from completing SEND requests back to the
1223 	 * initiator with status rnr_retry_count_exceeded. */
1224 	ctrlr_event_data.rnr_retry_count = 0x7;
1225 
1226 	/* When qpair is created without use of rdma cm API, an additional
1227 	 * information must be provided to initiator in the connection response:
1228 	 * whether qpair is using SRQ and its qp_num
1229 	 * Fields below are ignored by rdma cm if qpair has been
1230 	 * created using rdma cm API. */
1231 	ctrlr_event_data.srq = rqpair->srq ? 1 : 0;
1232 	ctrlr_event_data.qp_num = rqpair->qp_num;
1233 
1234 	rc = spdk_rdma_qp_accept(rqpair->rdma_qp, &ctrlr_event_data);
1235 	if (rc) {
1236 		SPDK_ERRLOG("Error %d on spdk_rdma_qp_accept\n", errno);
1237 	} else {
1238 		SPDK_DEBUGLOG(rdma, "Sent back the accept\n");
1239 	}
1240 
1241 	return rc;
1242 }
1243 
1244 static void
1245 nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
1246 {
1247 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
1248 
1249 	rej_data.recfmt = 0;
1250 	rej_data.sts = error;
1251 
1252 	rdma_reject(id, &rej_data, sizeof(rej_data));
1253 }
1254 
1255 static int
1256 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event)
1257 {
1258 	struct spdk_nvmf_rdma_transport *rtransport;
1259 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
1260 	struct spdk_nvmf_rdma_port	*port;
1261 	struct rdma_conn_param		*rdma_param = NULL;
1262 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
1263 	uint16_t			max_queue_depth;
1264 	uint16_t			max_read_depth;
1265 
1266 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1267 
1268 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
1269 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
1270 
1271 	rdma_param = &event->param.conn;
1272 	if (rdma_param->private_data == NULL ||
1273 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1274 		SPDK_ERRLOG("connect request: no private data provided\n");
1275 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
1276 		return -1;
1277 	}
1278 
1279 	private_data = rdma_param->private_data;
1280 	if (private_data->recfmt != 0) {
1281 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
1282 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
1283 		return -1;
1284 	}
1285 
1286 	SPDK_DEBUGLOG(rdma, "Connect Recv on fabric intf name %s, dev_name %s\n",
1287 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
1288 
1289 	port = event->listen_id->context;
1290 	SPDK_DEBUGLOG(rdma, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
1291 		      event->listen_id, event->listen_id->verbs, port);
1292 
1293 	/* Figure out the supported queue depth. This is a multi-step process
1294 	 * that takes into account hardware maximums, host provided values,
1295 	 * and our target's internal memory limits */
1296 
1297 	SPDK_DEBUGLOG(rdma, "Calculating Queue Depth\n");
1298 
1299 	/* Start with the maximum queue depth allowed by the target */
1300 	max_queue_depth = rtransport->transport.opts.max_queue_depth;
1301 	max_read_depth = rtransport->transport.opts.max_queue_depth;
1302 	SPDK_DEBUGLOG(rdma, "Target Max Queue Depth: %d\n",
1303 		      rtransport->transport.opts.max_queue_depth);
1304 
1305 	/* Next check the local NIC's hardware limitations */
1306 	SPDK_DEBUGLOG(rdma,
1307 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
1308 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
1309 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
1310 	max_read_depth = spdk_min(max_read_depth, port->device->attr.max_qp_init_rd_atom);
1311 
1312 	/* Next check the remote NIC's hardware limitations */
1313 	SPDK_DEBUGLOG(rdma,
1314 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
1315 		      rdma_param->initiator_depth, rdma_param->responder_resources);
1316 	/* from man3 rdma_get_cm_event
1317 	 * responder_resources - Specifies the number of responder resources that is requested by the recipient.
1318 	 * The responder_resources field must match the initiator depth specified by the remote node when running
1319 	 * the rdma_connect and rdma_accept functions. */
1320 	if (rdma_param->responder_resources != 0) {
1321 		if (private_data->qid) {
1322 			SPDK_DEBUGLOG(rdma, "Host (Initiator) is not allowed to use RDMA operations,"
1323 				      " responder_resources must be 0 but set to %u\n",
1324 				      rdma_param->responder_resources);
1325 		} else {
1326 			SPDK_WARNLOG("Host (Initiator) is not allowed to use RDMA operations,"
1327 				     " responder_resources must be 0 but set to %u\n",
1328 				     rdma_param->responder_resources);
1329 		}
1330 	}
1331 	/* from man3 rdma_get_cm_event
1332 	 * initiator_depth - Specifies the maximum number of outstanding RDMA read operations that the recipient holds.
1333 	 * The initiator_depth field must match the responder resources specified by the remote node when running
1334 	 * the rdma_connect and rdma_accept functions. */
1335 	if (rdma_param->initiator_depth == 0) {
1336 		SPDK_ERRLOG("Host (Initiator) doesn't support RDMA_READ or atomic operations\n");
1337 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_IRD);
1338 		return -1;
1339 	}
1340 	max_read_depth = spdk_min(max_read_depth, rdma_param->initiator_depth);
1341 
1342 	SPDK_DEBUGLOG(rdma, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1343 	SPDK_DEBUGLOG(rdma, "Host Send Queue Size: %d\n", private_data->hsqsize);
1344 	max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
1345 	max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
1346 
1347 	SPDK_DEBUGLOG(rdma, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
1348 		      max_queue_depth, max_read_depth);
1349 
1350 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
1351 	if (rqpair == NULL) {
1352 		SPDK_ERRLOG("Could not allocate new connection.\n");
1353 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1354 		return -1;
1355 	}
1356 
1357 	rqpair->device = port->device;
1358 	rqpair->max_queue_depth = max_queue_depth;
1359 	rqpair->max_read_depth = max_read_depth;
1360 	rqpair->cm_id = event->id;
1361 	rqpair->listen_id = event->listen_id;
1362 	rqpair->qpair.transport = transport;
1363 	STAILQ_INIT(&rqpair->ibv_events);
1364 	/* use qid from the private data to determine the qpair type
1365 	   qid will be set to the appropriate value when the controller is created */
1366 	rqpair->qpair.qid = private_data->qid;
1367 
1368 	event->id->context = &rqpair->qpair;
1369 
1370 	spdk_nvmf_tgt_new_qpair(transport->tgt, &rqpair->qpair);
1371 
1372 	return 0;
1373 }
1374 
1375 static inline void
1376 nvmf_rdma_setup_wr(struct ibv_send_wr *wr, struct ibv_send_wr *next,
1377 		   enum spdk_nvme_data_transfer xfer)
1378 {
1379 	if (xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1380 		wr->opcode = IBV_WR_RDMA_WRITE;
1381 		wr->send_flags = 0;
1382 		wr->next = next;
1383 	} else if (xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1384 		wr->opcode = IBV_WR_RDMA_READ;
1385 		wr->send_flags = IBV_SEND_SIGNALED;
1386 		wr->next = NULL;
1387 	} else {
1388 		assert(0);
1389 	}
1390 }
1391 
1392 static int
1393 nvmf_request_alloc_wrs(struct spdk_nvmf_rdma_transport *rtransport,
1394 		       struct spdk_nvmf_rdma_request *rdma_req,
1395 		       uint32_t num_sgl_descriptors)
1396 {
1397 	struct spdk_nvmf_rdma_request_data	*work_requests[SPDK_NVMF_MAX_SGL_ENTRIES];
1398 	struct spdk_nvmf_rdma_request_data	*current_data_wr;
1399 	uint32_t				i;
1400 
1401 	if (spdk_unlikely(num_sgl_descriptors > SPDK_NVMF_MAX_SGL_ENTRIES)) {
1402 		SPDK_ERRLOG("Requested too much entries (%u), the limit is %u\n",
1403 			    num_sgl_descriptors, SPDK_NVMF_MAX_SGL_ENTRIES);
1404 		return -EINVAL;
1405 	}
1406 
1407 	if (spdk_unlikely(spdk_mempool_get_bulk(rtransport->data_wr_pool, (void **)work_requests,
1408 						num_sgl_descriptors))) {
1409 		return -ENOMEM;
1410 	}
1411 
1412 	current_data_wr = &rdma_req->data;
1413 
1414 	for (i = 0; i < num_sgl_descriptors; i++) {
1415 		nvmf_rdma_setup_wr(&current_data_wr->wr, &work_requests[i]->wr, rdma_req->req.xfer);
1416 		current_data_wr->wr.next = &work_requests[i]->wr;
1417 		current_data_wr = work_requests[i];
1418 		current_data_wr->wr.sg_list = current_data_wr->sgl;
1419 		current_data_wr->wr.wr_id = rdma_req->data.wr.wr_id;
1420 	}
1421 
1422 	nvmf_rdma_setup_wr(&current_data_wr->wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1423 
1424 	return 0;
1425 }
1426 
1427 static inline void
1428 nvmf_rdma_setup_request(struct spdk_nvmf_rdma_request *rdma_req)
1429 {
1430 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1431 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1432 
1433 	wr->wr.rdma.rkey = sgl->keyed.key;
1434 	wr->wr.rdma.remote_addr = sgl->address;
1435 	nvmf_rdma_setup_wr(wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1436 }
1437 
1438 static inline void
1439 nvmf_rdma_update_remote_addr(struct spdk_nvmf_rdma_request *rdma_req, uint32_t num_wrs)
1440 {
1441 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1442 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1443 	uint32_t			i;
1444 	int				j;
1445 	uint64_t			remote_addr_offset = 0;
1446 
1447 	for (i = 0; i < num_wrs; ++i) {
1448 		wr->wr.rdma.rkey = sgl->keyed.key;
1449 		wr->wr.rdma.remote_addr = sgl->address + remote_addr_offset;
1450 		for (j = 0; j < wr->num_sge; ++j) {
1451 			remote_addr_offset += wr->sg_list[j].length;
1452 		}
1453 		wr = wr->next;
1454 	}
1455 }
1456 
1457 static int
1458 nvmf_rdma_fill_wr_sgl(struct spdk_nvmf_rdma_poll_group *rgroup,
1459 		      struct spdk_nvmf_rdma_device *device,
1460 		      struct spdk_nvmf_rdma_request *rdma_req,
1461 		      struct ibv_send_wr *wr,
1462 		      uint32_t total_length)
1463 {
1464 	struct spdk_rdma_memory_translation mem_translation;
1465 	struct ibv_sge	*sg_ele;
1466 	struct iovec *iov;
1467 	uint32_t lkey, remaining;
1468 	int rc;
1469 
1470 	wr->num_sge = 0;
1471 
1472 	while (total_length && wr->num_sge < SPDK_NVMF_MAX_SGL_ENTRIES) {
1473 		iov = &rdma_req->req.iov[rdma_req->iovpos];
1474 		rc = spdk_rdma_get_translation(device->map, iov->iov_base, iov->iov_len, &mem_translation);
1475 		if (spdk_unlikely(rc)) {
1476 			return rc;
1477 		}
1478 
1479 		lkey = spdk_rdma_memory_translation_get_lkey(&mem_translation);
1480 		sg_ele = &wr->sg_list[wr->num_sge];
1481 		remaining = spdk_min((uint32_t)iov->iov_len - rdma_req->offset, total_length);
1482 
1483 		sg_ele->lkey = lkey;
1484 		sg_ele->addr = (uintptr_t)iov->iov_base + rdma_req->offset;
1485 		sg_ele->length = remaining;
1486 		SPDK_DEBUGLOG(rdma, "sge[%d] %p addr 0x%"PRIx64", len %u\n", wr->num_sge, sg_ele, sg_ele->addr,
1487 			      sg_ele->length);
1488 		rdma_req->offset += sg_ele->length;
1489 		total_length -= sg_ele->length;
1490 		wr->num_sge++;
1491 
1492 		if (rdma_req->offset == iov->iov_len) {
1493 			rdma_req->offset = 0;
1494 			rdma_req->iovpos++;
1495 		}
1496 	}
1497 
1498 	if (spdk_unlikely(total_length)) {
1499 		SPDK_ERRLOG("Not enough SG entries to hold data buffer\n");
1500 		return -EINVAL;
1501 	}
1502 
1503 	return 0;
1504 }
1505 
1506 static int
1507 nvmf_rdma_fill_wr_sgl_with_dif(struct spdk_nvmf_rdma_poll_group *rgroup,
1508 			       struct spdk_nvmf_rdma_device *device,
1509 			       struct spdk_nvmf_rdma_request *rdma_req,
1510 			       struct ibv_send_wr *wr,
1511 			       uint32_t total_length,
1512 			       uint32_t num_extra_wrs)
1513 {
1514 	struct spdk_rdma_memory_translation mem_translation;
1515 	struct spdk_dif_ctx *dif_ctx = &rdma_req->req.dif.dif_ctx;
1516 	struct ibv_sge *sg_ele;
1517 	struct iovec *iov;
1518 	struct iovec *rdma_iov;
1519 	uint32_t lkey, remaining;
1520 	uint32_t remaining_data_block, data_block_size, md_size;
1521 	uint32_t sge_len;
1522 	int rc;
1523 
1524 	data_block_size = dif_ctx->block_size - dif_ctx->md_size;
1525 
1526 	if (spdk_likely(!rdma_req->req.stripped_data)) {
1527 		rdma_iov = rdma_req->req.iov;
1528 		remaining_data_block = data_block_size;
1529 		md_size = dif_ctx->md_size;
1530 	} else {
1531 		rdma_iov = rdma_req->req.stripped_data->iov;
1532 		total_length = total_length / dif_ctx->block_size * data_block_size;
1533 		remaining_data_block = total_length;
1534 		md_size = 0;
1535 	}
1536 
1537 	wr->num_sge = 0;
1538 
1539 	while (total_length && (num_extra_wrs || wr->num_sge < SPDK_NVMF_MAX_SGL_ENTRIES)) {
1540 		iov = rdma_iov + rdma_req->iovpos;
1541 		rc = spdk_rdma_get_translation(device->map, iov->iov_base, iov->iov_len, &mem_translation);
1542 		if (spdk_unlikely(rc)) {
1543 			return rc;
1544 		}
1545 
1546 		lkey = spdk_rdma_memory_translation_get_lkey(&mem_translation);
1547 		sg_ele = &wr->sg_list[wr->num_sge];
1548 		remaining = spdk_min((uint32_t)iov->iov_len - rdma_req->offset, total_length);
1549 
1550 		while (remaining) {
1551 			if (wr->num_sge >= SPDK_NVMF_MAX_SGL_ENTRIES) {
1552 				if (num_extra_wrs > 0 && wr->next) {
1553 					wr = wr->next;
1554 					wr->num_sge = 0;
1555 					sg_ele = &wr->sg_list[wr->num_sge];
1556 					num_extra_wrs--;
1557 				} else {
1558 					break;
1559 				}
1560 			}
1561 			sg_ele->lkey = lkey;
1562 			sg_ele->addr = (uintptr_t)((char *)iov->iov_base + rdma_req->offset);
1563 			sge_len = spdk_min(remaining, remaining_data_block);
1564 			sg_ele->length = sge_len;
1565 			SPDK_DEBUGLOG(rdma, "sge[%d] %p addr 0x%"PRIx64", len %u\n", wr->num_sge, sg_ele,
1566 				      sg_ele->addr, sg_ele->length);
1567 			remaining -= sge_len;
1568 			remaining_data_block -= sge_len;
1569 			rdma_req->offset += sge_len;
1570 			total_length -= sge_len;
1571 
1572 			sg_ele++;
1573 			wr->num_sge++;
1574 
1575 			if (remaining_data_block == 0) {
1576 				/* skip metadata */
1577 				rdma_req->offset += md_size;
1578 				total_length -= md_size;
1579 				/* Metadata that do not fit this IO buffer will be included in the next IO buffer */
1580 				remaining -= spdk_min(remaining, md_size);
1581 				remaining_data_block = data_block_size;
1582 			}
1583 
1584 			if (remaining == 0) {
1585 				/* By subtracting the size of the last IOV from the offset, we ensure that we skip
1586 				   the remaining metadata bits at the beginning of the next buffer */
1587 				rdma_req->offset -= spdk_min(iov->iov_len, rdma_req->offset);
1588 				rdma_req->iovpos++;
1589 			}
1590 		}
1591 	}
1592 
1593 	if (spdk_unlikely(total_length)) {
1594 		SPDK_ERRLOG("Not enough SG entries to hold data buffer\n");
1595 		return -EINVAL;
1596 	}
1597 
1598 	return 0;
1599 }
1600 
1601 static inline uint32_t
1602 nvmf_rdma_calc_num_wrs(uint32_t length, uint32_t io_unit_size, uint32_t block_size)
1603 {
1604 	/* estimate the number of SG entries and WRs needed to process the request */
1605 	uint32_t num_sge = 0;
1606 	uint32_t i;
1607 	uint32_t num_buffers = SPDK_CEIL_DIV(length, io_unit_size);
1608 
1609 	for (i = 0; i < num_buffers && length > 0; i++) {
1610 		uint32_t buffer_len = spdk_min(length, io_unit_size);
1611 		uint32_t num_sge_in_block = SPDK_CEIL_DIV(buffer_len, block_size);
1612 
1613 		if (num_sge_in_block * block_size > buffer_len) {
1614 			++num_sge_in_block;
1615 		}
1616 		num_sge += num_sge_in_block;
1617 		length -= buffer_len;
1618 	}
1619 	return SPDK_CEIL_DIV(num_sge, SPDK_NVMF_MAX_SGL_ENTRIES);
1620 }
1621 
1622 static int
1623 nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1624 			    struct spdk_nvmf_rdma_device *device,
1625 			    struct spdk_nvmf_rdma_request *rdma_req)
1626 {
1627 	struct spdk_nvmf_rdma_qpair		*rqpair;
1628 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1629 	struct spdk_nvmf_request		*req = &rdma_req->req;
1630 	struct ibv_send_wr			*wr = &rdma_req->data.wr;
1631 	int					rc;
1632 	uint32_t				num_wrs = 1;
1633 	uint32_t				length;
1634 
1635 	rqpair = SPDK_CONTAINEROF(req->qpair, struct spdk_nvmf_rdma_qpair, qpair);
1636 	rgroup = rqpair->poller->group;
1637 
1638 	/* rdma wr specifics */
1639 	nvmf_rdma_setup_request(rdma_req);
1640 
1641 	length = req->length;
1642 	if (spdk_unlikely(req->dif_enabled)) {
1643 		req->dif.orig_length = length;
1644 		length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
1645 		req->dif.elba_length = length;
1646 	}
1647 
1648 	rc = spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport,
1649 					   length);
1650 	if (spdk_unlikely(rc != 0)) {
1651 		return rc;
1652 	}
1653 
1654 	assert(req->iovcnt <= rqpair->max_send_sge);
1655 
1656 	/* When dif_insert_or_strip is true and the I/O data length is greater than one block,
1657 	 * the stripped_buffers are got for DIF stripping. */
1658 	if (spdk_unlikely(req->dif_enabled && (req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST)
1659 			  && (req->dif.elba_length > req->dif.dif_ctx.block_size))) {
1660 		rc = nvmf_request_get_stripped_buffers(req, &rgroup->group,
1661 						       &rtransport->transport, req->dif.orig_length);
1662 		if (rc != 0) {
1663 			SPDK_INFOLOG(rdma, "Get stripped buffers fail %d, fallback to req.iov.\n", rc);
1664 		}
1665 	}
1666 
1667 	rdma_req->iovpos = 0;
1668 
1669 	if (spdk_unlikely(req->dif_enabled)) {
1670 		num_wrs = nvmf_rdma_calc_num_wrs(length, rtransport->transport.opts.io_unit_size,
1671 						 req->dif.dif_ctx.block_size);
1672 		if (num_wrs > 1) {
1673 			rc = nvmf_request_alloc_wrs(rtransport, rdma_req, num_wrs - 1);
1674 			if (spdk_unlikely(rc != 0)) {
1675 				goto err_exit;
1676 			}
1677 		}
1678 
1679 		rc = nvmf_rdma_fill_wr_sgl_with_dif(rgroup, device, rdma_req, wr, length, num_wrs - 1);
1680 		if (spdk_unlikely(rc != 0)) {
1681 			goto err_exit;
1682 		}
1683 
1684 		if (num_wrs > 1) {
1685 			nvmf_rdma_update_remote_addr(rdma_req, num_wrs);
1686 		}
1687 	} else {
1688 		rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, wr, length);
1689 		if (spdk_unlikely(rc != 0)) {
1690 			goto err_exit;
1691 		}
1692 	}
1693 
1694 	/* set the number of outstanding data WRs for this request. */
1695 	rdma_req->num_outstanding_data_wr = num_wrs;
1696 
1697 	return rc;
1698 
1699 err_exit:
1700 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1701 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1702 	req->iovcnt = 0;
1703 	return rc;
1704 }
1705 
1706 static int
1707 nvmf_rdma_request_fill_iovs_multi_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1708 				      struct spdk_nvmf_rdma_device *device,
1709 				      struct spdk_nvmf_rdma_request *rdma_req)
1710 {
1711 	struct spdk_nvmf_rdma_qpair		*rqpair;
1712 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1713 	struct ibv_send_wr			*current_wr;
1714 	struct spdk_nvmf_request		*req = &rdma_req->req;
1715 	struct spdk_nvme_sgl_descriptor		*inline_segment, *desc;
1716 	uint32_t				num_sgl_descriptors;
1717 	uint32_t				lengths[SPDK_NVMF_MAX_SGL_ENTRIES], total_length = 0;
1718 	uint32_t				i;
1719 	int					rc;
1720 
1721 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1722 	rgroup = rqpair->poller->group;
1723 
1724 	inline_segment = &req->cmd->nvme_cmd.dptr.sgl1;
1725 	assert(inline_segment->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT);
1726 	assert(inline_segment->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET);
1727 
1728 	num_sgl_descriptors = inline_segment->unkeyed.length / sizeof(struct spdk_nvme_sgl_descriptor);
1729 	assert(num_sgl_descriptors <= SPDK_NVMF_MAX_SGL_ENTRIES);
1730 
1731 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1732 	for (i = 0; i < num_sgl_descriptors; i++) {
1733 		if (spdk_likely(!req->dif_enabled)) {
1734 			lengths[i] = desc->keyed.length;
1735 		} else {
1736 			req->dif.orig_length += desc->keyed.length;
1737 			lengths[i] = spdk_dif_get_length_with_md(desc->keyed.length, &req->dif.dif_ctx);
1738 			req->dif.elba_length += lengths[i];
1739 		}
1740 		total_length += lengths[i];
1741 		desc++;
1742 	}
1743 
1744 	if (spdk_unlikely(total_length > rtransport->transport.opts.max_io_size)) {
1745 		SPDK_ERRLOG("Multi SGL length 0x%x exceeds max io size 0x%x\n",
1746 			    total_length, rtransport->transport.opts.max_io_size);
1747 		req->rsp->nvme_cpl.status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1748 		return -EINVAL;
1749 	}
1750 
1751 	rc = nvmf_request_alloc_wrs(rtransport, rdma_req, num_sgl_descriptors - 1);
1752 	if (spdk_unlikely(rc != 0)) {
1753 		return -ENOMEM;
1754 	}
1755 
1756 	rc = spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport, total_length);
1757 	if (spdk_unlikely(rc != 0)) {
1758 		nvmf_rdma_request_free_data(rdma_req, rtransport);
1759 		return rc;
1760 	}
1761 
1762 	/* When dif_insert_or_strip is true and the I/O data length is greater than one block,
1763 	 * the stripped_buffers are got for DIF stripping. */
1764 	if (spdk_unlikely(req->dif_enabled && (req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST)
1765 			  && (req->dif.elba_length > req->dif.dif_ctx.block_size))) {
1766 		rc = nvmf_request_get_stripped_buffers(req, &rgroup->group,
1767 						       &rtransport->transport, req->dif.orig_length);
1768 		if (spdk_unlikely(rc != 0)) {
1769 			SPDK_INFOLOG(rdma, "Get stripped buffers fail %d, fallback to req.iov.\n", rc);
1770 		}
1771 	}
1772 
1773 	/* The first WR must always be the embedded data WR. This is how we unwind them later. */
1774 	current_wr = &rdma_req->data.wr;
1775 	assert(current_wr != NULL);
1776 
1777 	req->length = 0;
1778 	rdma_req->iovpos = 0;
1779 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1780 	for (i = 0; i < num_sgl_descriptors; i++) {
1781 		/* The descriptors must be keyed data block descriptors with an address, not an offset. */
1782 		if (spdk_unlikely(desc->generic.type != SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK ||
1783 				  desc->keyed.subtype != SPDK_NVME_SGL_SUBTYPE_ADDRESS)) {
1784 			rc = -EINVAL;
1785 			goto err_exit;
1786 		}
1787 
1788 		if (spdk_likely(!req->dif_enabled)) {
1789 			rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, current_wr, lengths[i]);
1790 		} else {
1791 			rc = nvmf_rdma_fill_wr_sgl_with_dif(rgroup, device, rdma_req, current_wr,
1792 							    lengths[i], 0);
1793 		}
1794 		if (spdk_unlikely(rc != 0)) {
1795 			rc = -ENOMEM;
1796 			goto err_exit;
1797 		}
1798 
1799 		req->length += desc->keyed.length;
1800 		current_wr->wr.rdma.rkey = desc->keyed.key;
1801 		current_wr->wr.rdma.remote_addr = desc->address;
1802 		current_wr = current_wr->next;
1803 		desc++;
1804 	}
1805 
1806 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1807 	/* Go back to the last descriptor in the list. */
1808 	desc--;
1809 	if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1810 		if (desc->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1811 			rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1812 			rdma_req->rsp.wr.imm_data = desc->keyed.key;
1813 		}
1814 	}
1815 #endif
1816 
1817 	rdma_req->num_outstanding_data_wr = num_sgl_descriptors;
1818 
1819 	return 0;
1820 
1821 err_exit:
1822 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1823 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1824 	return rc;
1825 }
1826 
1827 static int
1828 nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1829 			    struct spdk_nvmf_rdma_device *device,
1830 			    struct spdk_nvmf_rdma_request *rdma_req)
1831 {
1832 	struct spdk_nvmf_request		*req = &rdma_req->req;
1833 	struct spdk_nvme_cpl			*rsp;
1834 	struct spdk_nvme_sgl_descriptor		*sgl;
1835 	int					rc;
1836 	uint32_t				length;
1837 
1838 	rsp = &req->rsp->nvme_cpl;
1839 	sgl = &req->cmd->nvme_cmd.dptr.sgl1;
1840 
1841 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1842 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1843 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1844 
1845 		length = sgl->keyed.length;
1846 		if (spdk_unlikely(length > rtransport->transport.opts.max_io_size)) {
1847 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1848 				    length, rtransport->transport.opts.max_io_size);
1849 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1850 			return -1;
1851 		}
1852 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1853 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1854 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1855 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1856 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1857 			}
1858 		}
1859 #endif
1860 
1861 		/* fill request length and populate iovs */
1862 		req->length = length;
1863 
1864 		rc = nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req);
1865 		if (spdk_unlikely(rc < 0)) {
1866 			if (rc == -EINVAL) {
1867 				SPDK_ERRLOG("SGL length exceeds the max I/O size\n");
1868 				rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1869 				return -1;
1870 			}
1871 			/* No available buffers. Queue this request up. */
1872 			SPDK_DEBUGLOG(rdma, "No available large data buffers. Queueing request %p\n", rdma_req);
1873 			return 0;
1874 		}
1875 
1876 		SPDK_DEBUGLOG(rdma, "Request %p took %d buffer/s from central pool\n", rdma_req,
1877 			      req->iovcnt);
1878 
1879 		return 0;
1880 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1881 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1882 		uint64_t offset = sgl->address;
1883 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1884 
1885 		SPDK_DEBUGLOG(nvmf, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1886 			      offset, sgl->unkeyed.length);
1887 
1888 		if (spdk_unlikely(offset > max_len)) {
1889 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1890 				    offset, max_len);
1891 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1892 			return -1;
1893 		}
1894 		max_len -= (uint32_t)offset;
1895 
1896 		if (spdk_unlikely(sgl->unkeyed.length > max_len)) {
1897 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1898 				    sgl->unkeyed.length, max_len);
1899 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1900 			return -1;
1901 		}
1902 
1903 		rdma_req->num_outstanding_data_wr = 0;
1904 		req->data_from_pool = false;
1905 		req->length = sgl->unkeyed.length;
1906 
1907 		req->iov[0].iov_base = rdma_req->recv->buf + offset;
1908 		req->iov[0].iov_len = req->length;
1909 		req->iovcnt = 1;
1910 
1911 		return 0;
1912 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT &&
1913 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1914 
1915 		rc = nvmf_rdma_request_fill_iovs_multi_sgl(rtransport, device, rdma_req);
1916 		if (spdk_unlikely(rc == -ENOMEM)) {
1917 			SPDK_DEBUGLOG(rdma, "No available large data buffers. Queueing request %p\n", rdma_req);
1918 			return 0;
1919 		} else if (spdk_unlikely(rc == -EINVAL)) {
1920 			SPDK_ERRLOG("Multi SGL element request length exceeds the max I/O size\n");
1921 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1922 			return -1;
1923 		}
1924 
1925 		SPDK_DEBUGLOG(rdma, "Request %p took %d buffer/s from central pool\n", rdma_req,
1926 			      req->iovcnt);
1927 
1928 		return 0;
1929 	}
1930 
1931 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1932 		    sgl->generic.type, sgl->generic.subtype);
1933 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1934 	return -1;
1935 }
1936 
1937 static void
1938 _nvmf_rdma_request_free(struct spdk_nvmf_rdma_request *rdma_req,
1939 			struct spdk_nvmf_rdma_transport	*rtransport)
1940 {
1941 	struct spdk_nvmf_rdma_qpair		*rqpair;
1942 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1943 
1944 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1945 	if (rdma_req->req.data_from_pool) {
1946 		rgroup = rqpair->poller->group;
1947 
1948 		spdk_nvmf_request_free_buffers(&rdma_req->req, &rgroup->group, &rtransport->transport);
1949 	}
1950 	if (rdma_req->req.stripped_data) {
1951 		nvmf_request_free_stripped_buffers(&rdma_req->req,
1952 						   &rqpair->poller->group->group,
1953 						   &rtransport->transport);
1954 	}
1955 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1956 	rdma_req->req.length = 0;
1957 	rdma_req->req.iovcnt = 0;
1958 	rdma_req->offset = 0;
1959 	rdma_req->req.dif_enabled = false;
1960 	rdma_req->fused_failed = false;
1961 	rdma_req->transfer_wr = NULL;
1962 	if (rdma_req->fused_pair) {
1963 		/* This req was part of a valid fused pair, but failed before it got to
1964 		 * READ_TO_EXECUTE state.  This means we need to fail the other request
1965 		 * in the pair, because it is no longer part of a valid pair.  If the pair
1966 		 * already reached READY_TO_EXECUTE state, we need to kick it.
1967 		 */
1968 		rdma_req->fused_pair->fused_failed = true;
1969 		if (rdma_req->fused_pair->state == RDMA_REQUEST_STATE_READY_TO_EXECUTE) {
1970 			nvmf_rdma_request_process(rtransport, rdma_req->fused_pair);
1971 		}
1972 		rdma_req->fused_pair = NULL;
1973 	}
1974 	memset(&rdma_req->req.dif, 0, sizeof(rdma_req->req.dif));
1975 	rqpair->qd--;
1976 
1977 	STAILQ_INSERT_HEAD(&rqpair->resources->free_queue, rdma_req, state_link);
1978 	rdma_req->state = RDMA_REQUEST_STATE_FREE;
1979 }
1980 
1981 static void
1982 nvmf_rdma_check_fused_ordering(struct spdk_nvmf_rdma_transport *rtransport,
1983 			       struct spdk_nvmf_rdma_qpair *rqpair,
1984 			       struct spdk_nvmf_rdma_request *rdma_req)
1985 {
1986 	enum spdk_nvme_cmd_fuse last, next;
1987 
1988 	last = rqpair->fused_first ? rqpair->fused_first->req.cmd->nvme_cmd.fuse : SPDK_NVME_CMD_FUSE_NONE;
1989 	next = rdma_req->req.cmd->nvme_cmd.fuse;
1990 
1991 	assert(last != SPDK_NVME_CMD_FUSE_SECOND);
1992 
1993 	if (spdk_likely(last == SPDK_NVME_CMD_FUSE_NONE && next == SPDK_NVME_CMD_FUSE_NONE)) {
1994 		return;
1995 	}
1996 
1997 	if (last == SPDK_NVME_CMD_FUSE_FIRST) {
1998 		if (next == SPDK_NVME_CMD_FUSE_SECOND) {
1999 			/* This is a valid pair of fused commands.  Point them at each other
2000 			 * so they can be submitted consecutively once ready to be executed.
2001 			 */
2002 			rqpair->fused_first->fused_pair = rdma_req;
2003 			rdma_req->fused_pair = rqpair->fused_first;
2004 			rqpair->fused_first = NULL;
2005 			return;
2006 		} else {
2007 			/* Mark the last req as failed since it wasn't followed by a SECOND. */
2008 			rqpair->fused_first->fused_failed = true;
2009 
2010 			/* If the last req is in READY_TO_EXECUTE state, then call
2011 			 * nvmf_rdma_request_process(), otherwise nothing else will kick it.
2012 			 */
2013 			if (rqpair->fused_first->state == RDMA_REQUEST_STATE_READY_TO_EXECUTE) {
2014 				nvmf_rdma_request_process(rtransport, rqpair->fused_first);
2015 			}
2016 
2017 			rqpair->fused_first = NULL;
2018 		}
2019 	}
2020 
2021 	if (next == SPDK_NVME_CMD_FUSE_FIRST) {
2022 		/* Set rqpair->fused_first here so that we know to check that the next request
2023 		 * is a SECOND (and to fail this one if it isn't).
2024 		 */
2025 		rqpair->fused_first = rdma_req;
2026 	} else if (next == SPDK_NVME_CMD_FUSE_SECOND) {
2027 		/* Mark this req failed since it ia SECOND and the last one was not a FIRST. */
2028 		rdma_req->fused_failed = true;
2029 	}
2030 }
2031 
2032 bool
2033 nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
2034 			  struct spdk_nvmf_rdma_request *rdma_req)
2035 {
2036 	struct spdk_nvmf_rdma_qpair	*rqpair;
2037 	struct spdk_nvmf_rdma_device	*device;
2038 	struct spdk_nvmf_rdma_poll_group *rgroup;
2039 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
2040 	int				rc;
2041 	struct spdk_nvmf_rdma_recv	*rdma_recv;
2042 	enum spdk_nvmf_rdma_request_state prev_state;
2043 	bool				progress = false;
2044 	int				data_posted;
2045 	uint32_t			num_blocks, num_rdma_reads_available, qdepth;
2046 
2047 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
2048 	device = rqpair->device;
2049 	rgroup = rqpair->poller->group;
2050 
2051 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
2052 
2053 	/* If the queue pair is in an error state, force the request to the completed state
2054 	 * to release resources. */
2055 	if (spdk_unlikely(rqpair->ibv_in_error_state || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE)) {
2056 		switch (rdma_req->state) {
2057 		case RDMA_REQUEST_STATE_NEED_BUFFER:
2058 			STAILQ_REMOVE(&rgroup->group.pending_buf_queue, &rdma_req->req, spdk_nvmf_request, buf_link);
2059 			break;
2060 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
2061 			STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2062 			break;
2063 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
2064 			STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2065 			break;
2066 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING:
2067 			STAILQ_REMOVE(&rqpair->pending_rdma_send_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2068 			break;
2069 		default:
2070 			break;
2071 		}
2072 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2073 	}
2074 
2075 	/* The loop here is to allow for several back-to-back state changes. */
2076 	do {
2077 		prev_state = rdma_req->state;
2078 
2079 		SPDK_DEBUGLOG(rdma, "Request %p entering state %d\n", rdma_req, prev_state);
2080 
2081 		switch (rdma_req->state) {
2082 		case RDMA_REQUEST_STATE_FREE:
2083 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
2084 			 * to escape this state. */
2085 			break;
2086 		case RDMA_REQUEST_STATE_NEW:
2087 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
2088 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2089 			rdma_recv = rdma_req->recv;
2090 
2091 			/* The first element of the SGL is the NVMe command */
2092 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
2093 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
2094 			rdma_req->transfer_wr = &rdma_req->data.wr;
2095 
2096 			if (spdk_unlikely(rqpair->ibv_in_error_state || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE)) {
2097 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2098 				break;
2099 			}
2100 
2101 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&rdma_req->req, &rdma_req->req.dif.dif_ctx))) {
2102 				rdma_req->req.dif_enabled = true;
2103 			}
2104 
2105 			nvmf_rdma_check_fused_ordering(rtransport, rqpair, rdma_req);
2106 
2107 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2108 			rdma_req->rsp.wr.opcode = IBV_WR_SEND;
2109 			rdma_req->rsp.wr.imm_data = 0;
2110 #endif
2111 
2112 			/* The next state transition depends on the data transfer needs of this request. */
2113 			rdma_req->req.xfer = spdk_nvmf_req_get_xfer(&rdma_req->req);
2114 
2115 			if (spdk_unlikely(rdma_req->req.xfer == SPDK_NVME_DATA_BIDIRECTIONAL)) {
2116 				rsp->status.sct = SPDK_NVME_SCT_GENERIC;
2117 				rsp->status.sc = SPDK_NVME_SC_INVALID_OPCODE;
2118 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_send_queue, rdma_req, state_link);
2119 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING;
2120 				SPDK_DEBUGLOG(rdma, "Request %p: invalid xfer type (BIDIRECTIONAL)\n", rdma_req);
2121 				break;
2122 			}
2123 
2124 			/* If no data to transfer, ready to execute. */
2125 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
2126 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
2127 				break;
2128 			}
2129 
2130 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
2131 			STAILQ_INSERT_TAIL(&rgroup->group.pending_buf_queue, &rdma_req->req, buf_link);
2132 			break;
2133 		case RDMA_REQUEST_STATE_NEED_BUFFER:
2134 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
2135 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2136 
2137 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
2138 
2139 			if (&rdma_req->req != STAILQ_FIRST(&rgroup->group.pending_buf_queue)) {
2140 				/* This request needs to wait in line to obtain a buffer */
2141 				break;
2142 			}
2143 
2144 			/* Try to get a data buffer */
2145 			rc = nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
2146 			if (spdk_unlikely(rc < 0)) {
2147 				STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2148 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_send_queue, rdma_req, state_link);
2149 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING;
2150 				break;
2151 			}
2152 
2153 			if (rdma_req->req.iovcnt == 0) {
2154 				/* No buffers available. */
2155 				rgroup->stat.pending_data_buffer++;
2156 				break;
2157 			}
2158 
2159 			STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2160 
2161 			/* If data is transferring from host to controller and the data didn't
2162 			 * arrive using in capsule data, we need to do a transfer from the host.
2163 			 */
2164 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER &&
2165 			    rdma_req->req.data_from_pool) {
2166 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
2167 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
2168 				break;
2169 			}
2170 
2171 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
2172 			break;
2173 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
2174 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING, 0, 0,
2175 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2176 
2177 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_read_queue)) {
2178 				/* This request needs to wait in line to perform RDMA */
2179 				break;
2180 			}
2181 			assert(rqpair->max_send_depth >= rqpair->current_send_depth);
2182 			qdepth = rqpair->max_send_depth - rqpair->current_send_depth;
2183 			assert(rqpair->max_read_depth >= rqpair->current_read_depth);
2184 			num_rdma_reads_available = rqpair->max_read_depth - rqpair->current_read_depth;
2185 			if (rdma_req->num_outstanding_data_wr > qdepth ||
2186 			    rdma_req->num_outstanding_data_wr > num_rdma_reads_available) {
2187 				if (num_rdma_reads_available && qdepth) {
2188 					/* Send as much as we can */
2189 					request_prepare_transfer_in_part(&rdma_req->req, spdk_min(num_rdma_reads_available, qdepth));
2190 				} else {
2191 					/* We can only have so many WRs outstanding. we have to wait until some finish. */
2192 					rqpair->poller->stat.pending_rdma_read++;
2193 					break;
2194 				}
2195 			}
2196 
2197 			/* We have already verified that this request is the head of the queue. */
2198 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_read_queue, state_link);
2199 
2200 			rc = request_transfer_in(&rdma_req->req);
2201 			if (spdk_likely(rc == 0)) {
2202 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
2203 			} else {
2204 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
2205 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_send_queue, rdma_req, state_link);
2206 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING;
2207 			}
2208 			break;
2209 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2210 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2211 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2212 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
2213 			 * to escape this state. */
2214 			break;
2215 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
2216 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
2217 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2218 
2219 			if (spdk_unlikely(rdma_req->req.dif_enabled)) {
2220 				if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2221 					/* generate DIF for write operation */
2222 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2223 					assert(num_blocks > 0);
2224 
2225 					rc = spdk_dif_generate(rdma_req->req.iov, rdma_req->req.iovcnt,
2226 							       num_blocks, &rdma_req->req.dif.dif_ctx);
2227 					if (rc != 0) {
2228 						SPDK_ERRLOG("DIF generation failed\n");
2229 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2230 						spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2231 						break;
2232 					}
2233 				}
2234 
2235 				assert(rdma_req->req.dif.elba_length >= rdma_req->req.length);
2236 				/* set extended length before IO operation */
2237 				rdma_req->req.length = rdma_req->req.dif.elba_length;
2238 			}
2239 
2240 			if (rdma_req->req.cmd->nvme_cmd.fuse != SPDK_NVME_CMD_FUSE_NONE) {
2241 				if (rdma_req->fused_failed) {
2242 					/* This request failed FUSED semantics.  Fail it immediately, without
2243 					 * even sending it to the target layer.
2244 					 */
2245 					rsp->status.sct = SPDK_NVME_SCT_GENERIC;
2246 					rsp->status.sc = SPDK_NVME_SC_ABORTED_MISSING_FUSED;
2247 					STAILQ_INSERT_TAIL(&rqpair->pending_rdma_send_queue, rdma_req, state_link);
2248 					rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING;
2249 					break;
2250 				}
2251 
2252 				if (rdma_req->fused_pair == NULL ||
2253 				    rdma_req->fused_pair->state != RDMA_REQUEST_STATE_READY_TO_EXECUTE) {
2254 					/* This request is ready to execute, but either we don't know yet if it's
2255 					 * valid - i.e. this is a FIRST but we haven't received the next
2256 					 * request yet or the other request of this fused pair isn't ready to
2257 					 * execute.  So break here and this request will get processed later either
2258 					 * when the other request is ready or we find that this request isn't valid.
2259 					 */
2260 					break;
2261 				}
2262 			}
2263 
2264 			/* If we get to this point, and this request is a fused command, we know that
2265 			 * it is part of valid sequence (FIRST followed by a SECOND) and that both
2266 			 * requests are READY_TO_EXECUTE. So call spdk_nvmf_request_exec() both on this
2267 			 * request, and the other request of the fused pair, in the correct order.
2268 			 * Also clear the ->fused_pair pointers on both requests, since after this point
2269 			 * we no longer need to maintain the relationship between these two requests.
2270 			 */
2271 			if (rdma_req->req.cmd->nvme_cmd.fuse == SPDK_NVME_CMD_FUSE_SECOND) {
2272 				assert(rdma_req->fused_pair != NULL);
2273 				assert(rdma_req->fused_pair->fused_pair != NULL);
2274 				rdma_req->fused_pair->state = RDMA_REQUEST_STATE_EXECUTING;
2275 				spdk_nvmf_request_exec(&rdma_req->fused_pair->req);
2276 				rdma_req->fused_pair->fused_pair = NULL;
2277 				rdma_req->fused_pair = NULL;
2278 			}
2279 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
2280 			spdk_nvmf_request_exec(&rdma_req->req);
2281 			if (rdma_req->req.cmd->nvme_cmd.fuse == SPDK_NVME_CMD_FUSE_FIRST) {
2282 				assert(rdma_req->fused_pair != NULL);
2283 				assert(rdma_req->fused_pair->fused_pair != NULL);
2284 				rdma_req->fused_pair->state = RDMA_REQUEST_STATE_EXECUTING;
2285 				spdk_nvmf_request_exec(&rdma_req->fused_pair->req);
2286 				rdma_req->fused_pair->fused_pair = NULL;
2287 				rdma_req->fused_pair = NULL;
2288 			}
2289 			break;
2290 		case RDMA_REQUEST_STATE_EXECUTING:
2291 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
2292 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2293 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
2294 			 * to escape this state. */
2295 			break;
2296 		case RDMA_REQUEST_STATE_EXECUTED:
2297 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
2298 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2299 			if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
2300 			    rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2301 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_write_queue, rdma_req, state_link);
2302 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING;
2303 			} else {
2304 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_send_queue, rdma_req, state_link);
2305 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING;
2306 			}
2307 			if (spdk_unlikely(rdma_req->req.dif_enabled)) {
2308 				/* restore the original length */
2309 				rdma_req->req.length = rdma_req->req.dif.orig_length;
2310 
2311 				if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2312 					struct spdk_dif_error error_blk;
2313 
2314 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2315 					if (!rdma_req->req.stripped_data) {
2316 						rc = spdk_dif_verify(rdma_req->req.iov, rdma_req->req.iovcnt, num_blocks,
2317 								     &rdma_req->req.dif.dif_ctx, &error_blk);
2318 					} else {
2319 						rc = spdk_dif_verify_copy(rdma_req->req.stripped_data->iov,
2320 									  rdma_req->req.stripped_data->iovcnt,
2321 									  rdma_req->req.iov, rdma_req->req.iovcnt, num_blocks,
2322 									  &rdma_req->req.dif.dif_ctx, &error_blk);
2323 					}
2324 					if (rc) {
2325 						struct spdk_nvme_cpl *rsp = &rdma_req->req.rsp->nvme_cpl;
2326 
2327 						SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n", error_blk.err_type,
2328 							    error_blk.err_offset);
2329 						rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2330 						rsp->status.sc = nvmf_rdma_dif_error_to_compl_status(error_blk.err_type);
2331 						STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2332 						STAILQ_INSERT_TAIL(&rqpair->pending_rdma_send_queue, rdma_req, state_link);
2333 						rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING;
2334 					}
2335 				}
2336 			}
2337 			break;
2338 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
2339 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING, 0, 0,
2340 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2341 
2342 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_write_queue)) {
2343 				/* This request needs to wait in line to perform RDMA */
2344 				break;
2345 			}
2346 			if ((rqpair->current_send_depth + rdma_req->num_outstanding_data_wr + 1) >
2347 			    rqpair->max_send_depth) {
2348 				/* We can only have so many WRs outstanding. we have to wait until some finish.
2349 				 * +1 since each request has an additional wr in the resp. */
2350 				rqpair->poller->stat.pending_rdma_write++;
2351 				break;
2352 			}
2353 
2354 			/* We have already verified that this request is the head of the queue. */
2355 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_write_queue, state_link);
2356 
2357 			/* The data transfer will be kicked off from
2358 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
2359 			 * We verified that data + response fit into send queue, so we can go to the next state directly
2360 			 */
2361 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2362 			break;
2363 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING:
2364 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING, 0, 0,
2365 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2366 
2367 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_send_queue)) {
2368 				/* This request needs to wait in line to send the completion */
2369 				break;
2370 			}
2371 
2372 			assert(rqpair->current_send_depth <= rqpair->max_send_depth);
2373 			if (rqpair->current_send_depth == rqpair->max_send_depth) {
2374 				/* We can only have so many WRs outstanding. we have to wait until some finish */
2375 				rqpair->poller->stat.pending_rdma_send++;
2376 				break;
2377 			}
2378 
2379 			/* We have already verified that this request is the head of the queue. */
2380 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_send_queue, state_link);
2381 
2382 			/* The response sending will be kicked off from
2383 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
2384 			 */
2385 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2386 			break;
2387 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
2388 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
2389 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2390 			rc = request_transfer_out(&rdma_req->req, &data_posted);
2391 			assert(rc == 0); /* No good way to handle this currently */
2392 			if (spdk_unlikely(rc)) {
2393 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2394 			} else {
2395 				rdma_req->state = data_posted ? RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
2396 						  RDMA_REQUEST_STATE_COMPLETING;
2397 			}
2398 			break;
2399 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2400 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2401 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2402 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2403 			 * to escape this state. */
2404 			break;
2405 		case RDMA_REQUEST_STATE_COMPLETING:
2406 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
2407 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2408 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2409 			 * to escape this state. */
2410 			break;
2411 		case RDMA_REQUEST_STATE_COMPLETED:
2412 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
2413 					  (uintptr_t)rdma_req, (uintptr_t)rqpair);
2414 
2415 			rqpair->poller->stat.request_latency += spdk_get_ticks() - rdma_req->receive_tsc;
2416 			_nvmf_rdma_request_free(rdma_req, rtransport);
2417 			break;
2418 		case RDMA_REQUEST_NUM_STATES:
2419 		default:
2420 			assert(0);
2421 			break;
2422 		}
2423 
2424 		if (rdma_req->state != prev_state) {
2425 			progress = true;
2426 		}
2427 	} while (rdma_req->state != prev_state);
2428 
2429 	return progress;
2430 }
2431 
2432 /* Public API callbacks begin here */
2433 
2434 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
2435 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
2436 #define SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH 4096
2437 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
2438 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2439 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
2440 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
2441 #define SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS 4095
2442 #define SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE UINT32_MAX
2443 #define SPDK_NVMF_RDMA_DEFAULT_NO_SRQ false
2444 #define SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP false
2445 #define SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG 100
2446 #define SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC 1
2447 #define SPDK_NVMF_RDMA_DEFAULT_NO_WR_BATCHING false
2448 #define SPDK_NVMF_RDMA_DEFAULT_DATA_WR_POOL_SIZE 4095
2449 
2450 static void
2451 nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
2452 {
2453 	opts->max_queue_depth =		SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
2454 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2455 	opts->in_capsule_data_size =	SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
2456 	opts->max_io_size =		SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
2457 	opts->io_unit_size =		SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE;
2458 	opts->max_aq_depth =		SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
2459 	opts->num_shared_buffers =	SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS;
2460 	opts->buf_cache_size =		SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE;
2461 	opts->dif_insert_or_strip =	SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP;
2462 	opts->abort_timeout_sec =	SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC;
2463 	opts->transport_specific =      NULL;
2464 	opts->data_wr_pool_size	=	SPDK_NVMF_RDMA_DEFAULT_DATA_WR_POOL_SIZE;
2465 }
2466 
2467 static int nvmf_rdma_destroy(struct spdk_nvmf_transport *transport,
2468 			     spdk_nvmf_transport_destroy_done_cb cb_fn, void *cb_arg);
2469 
2470 static inline bool
2471 nvmf_rdma_is_rxe_device(struct spdk_nvmf_rdma_device *device)
2472 {
2473 	return device->attr.vendor_id == SPDK_RDMA_RXE_VENDOR_ID_OLD ||
2474 	       device->attr.vendor_id == SPDK_RDMA_RXE_VENDOR_ID_NEW;
2475 }
2476 
2477 static int nvmf_rdma_accept(void *ctx);
2478 static bool nvmf_rdma_retry_listen_port(struct spdk_nvmf_rdma_transport *rtransport);
2479 static void destroy_ib_device(struct spdk_nvmf_rdma_transport *rtransport,
2480 			      struct spdk_nvmf_rdma_device *device);
2481 
2482 static int
2483 create_ib_device(struct spdk_nvmf_rdma_transport *rtransport, struct ibv_context *context,
2484 		 struct spdk_nvmf_rdma_device **new_device)
2485 {
2486 	struct spdk_nvmf_rdma_device	*device;
2487 	int				flag = 0;
2488 	int				rc = 0;
2489 
2490 	device = calloc(1, sizeof(*device));
2491 	if (!device) {
2492 		SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
2493 		return -ENOMEM;
2494 	}
2495 	device->context = context;
2496 	rc = ibv_query_device(device->context, &device->attr);
2497 	if (rc < 0) {
2498 		SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2499 		free(device);
2500 		return rc;
2501 	}
2502 
2503 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2504 	if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
2505 		SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
2506 		SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
2507 	}
2508 
2509 	/**
2510 	 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
2511 	 * The Soft-RoCE RXE driver does not currently support send with invalidate,
2512 	 * but incorrectly reports that it does. There are changes making their way
2513 	 * through the kernel now that will enable this feature. When they are merged,
2514 	 * we can conditionally enable this feature.
2515 	 *
2516 	 * TODO: enable this for versions of the kernel rxe driver that support it.
2517 	 */
2518 	if (nvmf_rdma_is_rxe_device(device)) {
2519 		device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
2520 	}
2521 #endif
2522 
2523 	/* set up device context async ev fd as NON_BLOCKING */
2524 	flag = fcntl(device->context->async_fd, F_GETFL);
2525 	rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
2526 	if (rc < 0) {
2527 		SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
2528 		free(device);
2529 		return rc;
2530 	}
2531 
2532 	TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
2533 	SPDK_DEBUGLOG(rdma, "New device %p is added to RDMA trasport\n", device);
2534 
2535 	if (g_nvmf_hooks.get_ibv_pd) {
2536 		device->pd = g_nvmf_hooks.get_ibv_pd(NULL, device->context);
2537 	} else {
2538 		device->pd = ibv_alloc_pd(device->context);
2539 	}
2540 
2541 	if (!device->pd) {
2542 		SPDK_ERRLOG("Unable to allocate protection domain.\n");
2543 		destroy_ib_device(rtransport, device);
2544 		return -ENOMEM;
2545 	}
2546 
2547 	assert(device->map == NULL);
2548 
2549 	device->map = spdk_rdma_create_mem_map(device->pd, &g_nvmf_hooks, SPDK_RDMA_MEMORY_MAP_ROLE_TARGET);
2550 	if (!device->map) {
2551 		SPDK_ERRLOG("Unable to allocate memory map for listen address\n");
2552 		destroy_ib_device(rtransport, device);
2553 		return -ENOMEM;
2554 	}
2555 
2556 	assert(device->map != NULL);
2557 	assert(device->pd != NULL);
2558 
2559 	if (new_device) {
2560 		*new_device = device;
2561 	}
2562 	SPDK_NOTICELOG("Create IB device %s(%p/%p) succeed.\n", ibv_get_device_name(context->device),
2563 		       device, context);
2564 
2565 	return 0;
2566 }
2567 
2568 static void
2569 free_poll_fds(struct spdk_nvmf_rdma_transport *rtransport)
2570 {
2571 	if (rtransport->poll_fds) {
2572 		free(rtransport->poll_fds);
2573 		rtransport->poll_fds = NULL;
2574 	}
2575 	rtransport->npoll_fds = 0;
2576 }
2577 
2578 static int
2579 generate_poll_fds(struct spdk_nvmf_rdma_transport *rtransport)
2580 {
2581 	/* Set up poll descriptor array to monitor events from RDMA and IB
2582 	 * in a single poll syscall
2583 	 */
2584 	int device_count = 0;
2585 	int i = 0;
2586 	struct spdk_nvmf_rdma_device *device, *tmp;
2587 
2588 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2589 		device_count++;
2590 	}
2591 
2592 	rtransport->npoll_fds = device_count + 1;
2593 
2594 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
2595 	if (rtransport->poll_fds == NULL) {
2596 		SPDK_ERRLOG("poll_fds allocation failed\n");
2597 		return -ENOMEM;
2598 	}
2599 
2600 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
2601 	rtransport->poll_fds[i++].events = POLLIN;
2602 
2603 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2604 		rtransport->poll_fds[i].fd = device->context->async_fd;
2605 		rtransport->poll_fds[i++].events = POLLIN;
2606 	}
2607 
2608 	return 0;
2609 }
2610 
2611 static struct spdk_nvmf_transport *
2612 nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
2613 {
2614 	int rc;
2615 	struct spdk_nvmf_rdma_transport *rtransport;
2616 	struct spdk_nvmf_rdma_device	*device;
2617 	struct ibv_context		**contexts;
2618 	size_t				data_wr_pool_size;
2619 	uint32_t			i;
2620 	int				flag;
2621 	uint32_t			sge_count;
2622 	uint32_t			min_shared_buffers;
2623 	uint32_t			min_in_capsule_data_size;
2624 	int				max_device_sge = SPDK_NVMF_MAX_SGL_ENTRIES;
2625 
2626 	rtransport = calloc(1, sizeof(*rtransport));
2627 	if (!rtransport) {
2628 		return NULL;
2629 	}
2630 
2631 	TAILQ_INIT(&rtransport->devices);
2632 	TAILQ_INIT(&rtransport->ports);
2633 	TAILQ_INIT(&rtransport->poll_groups);
2634 	TAILQ_INIT(&rtransport->retry_ports);
2635 
2636 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
2637 	rtransport->rdma_opts.num_cqe = DEFAULT_NVMF_RDMA_CQ_SIZE;
2638 	rtransport->rdma_opts.max_srq_depth = SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH;
2639 	rtransport->rdma_opts.no_srq = SPDK_NVMF_RDMA_DEFAULT_NO_SRQ;
2640 	rtransport->rdma_opts.acceptor_backlog = SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2641 	rtransport->rdma_opts.no_wr_batching = SPDK_NVMF_RDMA_DEFAULT_NO_WR_BATCHING;
2642 	if (opts->transport_specific != NULL &&
2643 	    spdk_json_decode_object_relaxed(opts->transport_specific, rdma_transport_opts_decoder,
2644 					    SPDK_COUNTOF(rdma_transport_opts_decoder),
2645 					    &rtransport->rdma_opts)) {
2646 		SPDK_ERRLOG("spdk_json_decode_object_relaxed failed\n");
2647 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2648 		return NULL;
2649 	}
2650 
2651 	SPDK_INFOLOG(rdma, "*** RDMA Transport Init ***\n"
2652 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
2653 		     "  max_io_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
2654 		     "  in_capsule_data_size=%d, max_aq_depth=%d,\n"
2655 		     "  num_shared_buffers=%d, num_cqe=%d, max_srq_depth=%d, no_srq=%d,"
2656 		     "  acceptor_backlog=%d, no_wr_batching=%d abort_timeout_sec=%d\n",
2657 		     opts->max_queue_depth,
2658 		     opts->max_io_size,
2659 		     opts->max_qpairs_per_ctrlr - 1,
2660 		     opts->io_unit_size,
2661 		     opts->in_capsule_data_size,
2662 		     opts->max_aq_depth,
2663 		     opts->num_shared_buffers,
2664 		     rtransport->rdma_opts.num_cqe,
2665 		     rtransport->rdma_opts.max_srq_depth,
2666 		     rtransport->rdma_opts.no_srq,
2667 		     rtransport->rdma_opts.acceptor_backlog,
2668 		     rtransport->rdma_opts.no_wr_batching,
2669 		     opts->abort_timeout_sec);
2670 
2671 	/* I/O unit size cannot be larger than max I/O size */
2672 	if (opts->io_unit_size > opts->max_io_size) {
2673 		opts->io_unit_size = opts->max_io_size;
2674 	}
2675 
2676 	if (rtransport->rdma_opts.acceptor_backlog <= 0) {
2677 		SPDK_ERRLOG("The acceptor backlog cannot be less than 1, setting to the default value of (%d).\n",
2678 			    SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG);
2679 		rtransport->rdma_opts.acceptor_backlog = SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2680 	}
2681 
2682 	if (opts->num_shared_buffers < (SPDK_NVMF_MAX_SGL_ENTRIES * 2)) {
2683 		SPDK_ERRLOG("The number of shared data buffers (%d) is less than"
2684 			    "the minimum number required to guarantee that forward progress can be made (%d)\n",
2685 			    opts->num_shared_buffers, (SPDK_NVMF_MAX_SGL_ENTRIES * 2));
2686 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2687 		return NULL;
2688 	}
2689 
2690 	/* If buf_cache_size == UINT32_MAX, we will dynamically pick a cache size later that we know will fit. */
2691 	if (opts->buf_cache_size < UINT32_MAX) {
2692 		min_shared_buffers = spdk_env_get_core_count() * opts->buf_cache_size;
2693 		if (min_shared_buffers > opts->num_shared_buffers) {
2694 			SPDK_ERRLOG("There are not enough buffers to satisfy"
2695 				    "per-poll group caches for each thread. (%" PRIu32 ")"
2696 				    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
2697 			SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
2698 			nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2699 			return NULL;
2700 		}
2701 	}
2702 
2703 	sge_count = opts->max_io_size / opts->io_unit_size;
2704 	if (sge_count > NVMF_DEFAULT_TX_SGE) {
2705 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
2706 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2707 		return NULL;
2708 	}
2709 
2710 	min_in_capsule_data_size = sizeof(struct spdk_nvme_sgl_descriptor) * SPDK_NVMF_MAX_SGL_ENTRIES;
2711 	if (opts->in_capsule_data_size < min_in_capsule_data_size) {
2712 		SPDK_WARNLOG("In capsule data size is set to %u, this is minimum size required to support msdbd=16\n",
2713 			     min_in_capsule_data_size);
2714 		opts->in_capsule_data_size = min_in_capsule_data_size;
2715 	}
2716 
2717 	rtransport->event_channel = rdma_create_event_channel();
2718 	if (rtransport->event_channel == NULL) {
2719 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
2720 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2721 		return NULL;
2722 	}
2723 
2724 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
2725 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2726 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
2727 			    rtransport->event_channel->fd, spdk_strerror(errno));
2728 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2729 		return NULL;
2730 	}
2731 
2732 	data_wr_pool_size = opts->data_wr_pool_size;
2733 	if (data_wr_pool_size < SPDK_NVMF_MAX_SGL_ENTRIES * 2 * spdk_env_get_core_count()) {
2734 		data_wr_pool_size = SPDK_NVMF_MAX_SGL_ENTRIES * 2 * spdk_env_get_core_count();
2735 		SPDK_NOTICELOG("data_wr_pool_size is changed to %zu to guarantee enough cache for handling "
2736 			       "at least one IO in each core\n", data_wr_pool_size);
2737 	}
2738 	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data", data_wr_pool_size,
2739 				   sizeof(struct spdk_nvmf_rdma_request_data), SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
2740 				   SPDK_ENV_SOCKET_ID_ANY);
2741 	if (!rtransport->data_wr_pool) {
2742 		if (spdk_mempool_lookup("spdk_nvmf_rdma_wr_data") != NULL) {
2743 			SPDK_ERRLOG("Unable to allocate work request pool for poll group: already exists\n");
2744 			SPDK_ERRLOG("Probably running in multiprocess environment, which is "
2745 				    "unsupported by the nvmf library\n");
2746 		} else {
2747 			SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");
2748 		}
2749 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2750 		return NULL;
2751 	}
2752 
2753 	contexts = rdma_get_devices(NULL);
2754 	if (contexts == NULL) {
2755 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2756 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2757 		return NULL;
2758 	}
2759 
2760 	i = 0;
2761 	rc = 0;
2762 	while (contexts[i] != NULL) {
2763 		rc = create_ib_device(rtransport, contexts[i], &device);
2764 		if (rc < 0) {
2765 			break;
2766 		}
2767 		i++;
2768 		max_device_sge = spdk_min(max_device_sge, device->attr.max_sge);
2769 		device->is_ready = true;
2770 	}
2771 	rdma_free_devices(contexts);
2772 
2773 	if (opts->io_unit_size * max_device_sge < opts->max_io_size) {
2774 		/* divide and round up. */
2775 		opts->io_unit_size = (opts->max_io_size + max_device_sge - 1) / max_device_sge;
2776 
2777 		/* round up to the nearest 4k. */
2778 		opts->io_unit_size = (opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT - 1) & ~NVMF_DATA_BUFFER_MASK;
2779 
2780 		opts->io_unit_size = spdk_max(opts->io_unit_size, SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
2781 		SPDK_NOTICELOG("Adjusting the io unit size to fit the device's maximum I/O size. New I/O unit size %u\n",
2782 			       opts->io_unit_size);
2783 	}
2784 
2785 	if (rc < 0) {
2786 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2787 		return NULL;
2788 	}
2789 
2790 	rc = generate_poll_fds(rtransport);
2791 	if (rc < 0) {
2792 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2793 		return NULL;
2794 	}
2795 
2796 	rtransport->accept_poller = SPDK_POLLER_REGISTER(nvmf_rdma_accept, &rtransport->transport,
2797 				    opts->acceptor_poll_rate);
2798 	if (!rtransport->accept_poller) {
2799 		nvmf_rdma_destroy(&rtransport->transport, NULL, NULL);
2800 		return NULL;
2801 	}
2802 
2803 	return &rtransport->transport;
2804 }
2805 
2806 static void
2807 destroy_ib_device(struct spdk_nvmf_rdma_transport *rtransport,
2808 		  struct spdk_nvmf_rdma_device *device)
2809 {
2810 	TAILQ_REMOVE(&rtransport->devices, device, link);
2811 	spdk_rdma_free_mem_map(&device->map);
2812 	if (device->pd) {
2813 		if (!g_nvmf_hooks.get_ibv_pd) {
2814 			ibv_dealloc_pd(device->pd);
2815 		}
2816 	}
2817 	SPDK_DEBUGLOG(rdma, "IB device [%p] is destroyed.\n", device);
2818 	free(device);
2819 }
2820 
2821 static void
2822 nvmf_rdma_dump_opts(struct spdk_nvmf_transport *transport, struct spdk_json_write_ctx *w)
2823 {
2824 	struct spdk_nvmf_rdma_transport	*rtransport;
2825 	assert(w != NULL);
2826 
2827 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2828 	spdk_json_write_named_uint32(w, "max_srq_depth", rtransport->rdma_opts.max_srq_depth);
2829 	spdk_json_write_named_bool(w, "no_srq", rtransport->rdma_opts.no_srq);
2830 	if (rtransport->rdma_opts.no_srq == true) {
2831 		spdk_json_write_named_int32(w, "num_cqe", rtransport->rdma_opts.num_cqe);
2832 	}
2833 	spdk_json_write_named_int32(w, "acceptor_backlog", rtransport->rdma_opts.acceptor_backlog);
2834 	spdk_json_write_named_bool(w, "no_wr_batching", rtransport->rdma_opts.no_wr_batching);
2835 }
2836 
2837 static int
2838 nvmf_rdma_destroy(struct spdk_nvmf_transport *transport,
2839 		  spdk_nvmf_transport_destroy_done_cb cb_fn, void *cb_arg)
2840 {
2841 	struct spdk_nvmf_rdma_transport	*rtransport;
2842 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
2843 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
2844 
2845 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2846 
2847 	TAILQ_FOREACH_SAFE(port, &rtransport->retry_ports, link, port_tmp) {
2848 		TAILQ_REMOVE(&rtransport->retry_ports, port, link);
2849 		free(port);
2850 	}
2851 
2852 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
2853 		TAILQ_REMOVE(&rtransport->ports, port, link);
2854 		rdma_destroy_id(port->id);
2855 		free(port);
2856 	}
2857 
2858 	free_poll_fds(rtransport);
2859 
2860 	if (rtransport->event_channel != NULL) {
2861 		rdma_destroy_event_channel(rtransport->event_channel);
2862 	}
2863 
2864 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
2865 		destroy_ib_device(rtransport, device);
2866 	}
2867 
2868 	if (rtransport->data_wr_pool != NULL) {
2869 		if (spdk_mempool_count(rtransport->data_wr_pool) !=
2870 		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {
2871 			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",
2872 				    spdk_mempool_count(rtransport->data_wr_pool),
2873 				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);
2874 		}
2875 	}
2876 
2877 	spdk_mempool_free(rtransport->data_wr_pool);
2878 
2879 	spdk_poller_unregister(&rtransport->accept_poller);
2880 	free(rtransport);
2881 
2882 	if (cb_fn) {
2883 		cb_fn(cb_arg);
2884 	}
2885 	return 0;
2886 }
2887 
2888 static int nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2889 				     struct spdk_nvme_transport_id *trid,
2890 				     bool peer);
2891 
2892 static bool nvmf_rdma_rescan_devices(struct spdk_nvmf_rdma_transport *rtransport);
2893 
2894 static int
2895 nvmf_rdma_listen(struct spdk_nvmf_transport *transport, const struct spdk_nvme_transport_id *trid,
2896 		 struct spdk_nvmf_listen_opts *listen_opts)
2897 {
2898 	struct spdk_nvmf_rdma_transport	*rtransport;
2899 	struct spdk_nvmf_rdma_device	*device;
2900 	struct spdk_nvmf_rdma_port	*port, *tmp_port;
2901 	struct addrinfo			*res;
2902 	struct addrinfo			hints;
2903 	int				family;
2904 	int				rc;
2905 	long int			port_val;
2906 	bool				is_retry = false;
2907 
2908 	if (!strlen(trid->trsvcid)) {
2909 		SPDK_ERRLOG("Service id is required\n");
2910 		return -EINVAL;
2911 	}
2912 
2913 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2914 	assert(rtransport->event_channel != NULL);
2915 
2916 	port = calloc(1, sizeof(*port));
2917 	if (!port) {
2918 		SPDK_ERRLOG("Port allocation failed\n");
2919 		return -ENOMEM;
2920 	}
2921 
2922 	port->trid = trid;
2923 
2924 	switch (trid->adrfam) {
2925 	case SPDK_NVMF_ADRFAM_IPV4:
2926 		family = AF_INET;
2927 		break;
2928 	case SPDK_NVMF_ADRFAM_IPV6:
2929 		family = AF_INET6;
2930 		break;
2931 	default:
2932 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", trid->adrfam);
2933 		free(port);
2934 		return -EINVAL;
2935 	}
2936 
2937 	memset(&hints, 0, sizeof(hints));
2938 	hints.ai_family = family;
2939 	hints.ai_flags = AI_NUMERICSERV;
2940 	hints.ai_socktype = SOCK_STREAM;
2941 	hints.ai_protocol = 0;
2942 
2943 	/* Range check the trsvcid. Fail in 3 cases:
2944 	 * < 0: means that spdk_strtol hit an error
2945 	 * 0: this results in ephemeral port which we don't want
2946 	 * > 65535: port too high
2947 	 */
2948 	port_val = spdk_strtol(trid->trsvcid, 10);
2949 	if (port_val <= 0 || port_val > 65535) {
2950 		SPDK_ERRLOG("invalid trsvcid %s\n", trid->trsvcid);
2951 		free(port);
2952 		return -EINVAL;
2953 	}
2954 
2955 	rc = getaddrinfo(trid->traddr, trid->trsvcid, &hints, &res);
2956 	if (rc) {
2957 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
2958 		free(port);
2959 		return -(abs(rc));
2960 	}
2961 
2962 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
2963 	if (rc < 0) {
2964 		SPDK_ERRLOG("rdma_create_id() failed\n");
2965 		freeaddrinfo(res);
2966 		free(port);
2967 		return rc;
2968 	}
2969 
2970 	rc = rdma_bind_addr(port->id, res->ai_addr);
2971 	freeaddrinfo(res);
2972 
2973 	if (rc < 0) {
2974 		TAILQ_FOREACH(tmp_port, &rtransport->retry_ports, link) {
2975 			if (spdk_nvme_transport_id_compare(tmp_port->trid, trid) == 0) {
2976 				is_retry = true;
2977 				break;
2978 			}
2979 		}
2980 		if (!is_retry) {
2981 			SPDK_ERRLOG("rdma_bind_addr() failed\n");
2982 		}
2983 		rdma_destroy_id(port->id);
2984 		free(port);
2985 		return rc;
2986 	}
2987 
2988 	if (!port->id->verbs) {
2989 		SPDK_ERRLOG("ibv_context is null\n");
2990 		rdma_destroy_id(port->id);
2991 		free(port);
2992 		return -1;
2993 	}
2994 
2995 	rc = rdma_listen(port->id, rtransport->rdma_opts.acceptor_backlog);
2996 	if (rc < 0) {
2997 		SPDK_ERRLOG("rdma_listen() failed\n");
2998 		rdma_destroy_id(port->id);
2999 		free(port);
3000 		return rc;
3001 	}
3002 
3003 	TAILQ_FOREACH(device, &rtransport->devices, link) {
3004 		if (device->context == port->id->verbs && device->is_ready) {
3005 			port->device = device;
3006 			break;
3007 		}
3008 	}
3009 	if (!port->device) {
3010 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
3011 			    port->id->verbs);
3012 		rdma_destroy_id(port->id);
3013 		free(port);
3014 		nvmf_rdma_rescan_devices(rtransport);
3015 		return -EINVAL;
3016 	}
3017 
3018 	SPDK_NOTICELOG("*** NVMe/RDMA Target Listening on %s port %s ***\n",
3019 		       trid->traddr, trid->trsvcid);
3020 
3021 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
3022 	return 0;
3023 }
3024 
3025 static void
3026 nvmf_rdma_stop_listen_ex(struct spdk_nvmf_transport *transport,
3027 			 const struct spdk_nvme_transport_id *trid, bool need_retry)
3028 {
3029 	struct spdk_nvmf_rdma_transport	*rtransport;
3030 	struct spdk_nvmf_rdma_port	*port, *tmp;
3031 
3032 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3033 
3034 	if (!need_retry) {
3035 		TAILQ_FOREACH_SAFE(port, &rtransport->retry_ports, link, tmp) {
3036 			if (spdk_nvme_transport_id_compare(port->trid, trid) == 0) {
3037 				TAILQ_REMOVE(&rtransport->retry_ports, port, link);
3038 				free(port);
3039 			}
3040 		}
3041 	}
3042 
3043 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
3044 		if (spdk_nvme_transport_id_compare(port->trid, trid) == 0) {
3045 			SPDK_DEBUGLOG(rdma, "Port %s:%s removed. need retry: %d\n",
3046 				      port->trid->traddr, port->trid->trsvcid, need_retry);
3047 			TAILQ_REMOVE(&rtransport->ports, port, link);
3048 			rdma_destroy_id(port->id);
3049 			port->id = NULL;
3050 			port->device = NULL;
3051 			if (need_retry) {
3052 				TAILQ_INSERT_TAIL(&rtransport->retry_ports, port, link);
3053 			} else {
3054 				free(port);
3055 			}
3056 			break;
3057 		}
3058 	}
3059 }
3060 
3061 static void
3062 nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
3063 		      const struct spdk_nvme_transport_id *trid)
3064 {
3065 	nvmf_rdma_stop_listen_ex(transport, trid, false);
3066 }
3067 
3068 static void _nvmf_rdma_register_poller_in_group(void *c);
3069 static void _nvmf_rdma_remove_poller_in_group(void *c);
3070 
3071 static bool
3072 nvmf_rdma_all_pollers_management_done(void *c)
3073 {
3074 	struct poller_manage_ctx	*ctx = c;
3075 	int				counter;
3076 
3077 	counter = __atomic_sub_fetch(ctx->inflight_op_counter, 1, __ATOMIC_SEQ_CST);
3078 	SPDK_DEBUGLOG(rdma, "nvmf_rdma_all_pollers_management_done called. counter: %d, poller: %p\n",
3079 		      counter, ctx->rpoller);
3080 
3081 	if (counter == 0) {
3082 		free((void *)ctx->inflight_op_counter);
3083 	}
3084 	free(ctx);
3085 
3086 	return counter == 0;
3087 }
3088 
3089 static int
3090 nvmf_rdma_manage_poller(struct spdk_nvmf_rdma_transport *rtransport,
3091 			struct spdk_nvmf_rdma_device *device, bool *has_inflight, bool is_add)
3092 {
3093 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3094 	struct spdk_nvmf_rdma_poller		*rpoller;
3095 	struct spdk_nvmf_poll_group		*poll_group;
3096 	struct poller_manage_ctx		*ctx;
3097 	bool					found;
3098 	int					*inflight_counter;
3099 	spdk_msg_fn				do_fn;
3100 
3101 	*has_inflight = false;
3102 	do_fn = is_add ? _nvmf_rdma_register_poller_in_group : _nvmf_rdma_remove_poller_in_group;
3103 	inflight_counter = calloc(1, sizeof(int));
3104 	if (!inflight_counter) {
3105 		SPDK_ERRLOG("Failed to allocate inflight counter when removing pollers\n");
3106 		return -ENOMEM;
3107 	}
3108 
3109 	TAILQ_FOREACH(rgroup, &rtransport->poll_groups, link) {
3110 		(*inflight_counter)++;
3111 	}
3112 
3113 	TAILQ_FOREACH(rgroup, &rtransport->poll_groups, link) {
3114 		found = false;
3115 		TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3116 			if (rpoller->device == device) {
3117 				found = true;
3118 				break;
3119 			}
3120 		}
3121 		if (found == is_add) {
3122 			__atomic_fetch_sub(inflight_counter, 1, __ATOMIC_SEQ_CST);
3123 			continue;
3124 		}
3125 
3126 		ctx = calloc(1, sizeof(struct poller_manage_ctx));
3127 		if (!ctx) {
3128 			SPDK_ERRLOG("Failed to allocate poller_manage_ctx when removing pollers\n");
3129 			if (!*has_inflight) {
3130 				free(inflight_counter);
3131 			}
3132 			return -ENOMEM;
3133 		}
3134 
3135 		ctx->rtransport = rtransport;
3136 		ctx->rgroup = rgroup;
3137 		ctx->rpoller = rpoller;
3138 		ctx->device = device;
3139 		ctx->thread = spdk_get_thread();
3140 		ctx->inflight_op_counter = inflight_counter;
3141 		*has_inflight = true;
3142 
3143 		poll_group = rgroup->group.group;
3144 		if (poll_group->thread != spdk_get_thread()) {
3145 			spdk_thread_send_msg(poll_group->thread, do_fn, ctx);
3146 		} else {
3147 			do_fn(ctx);
3148 		}
3149 	}
3150 
3151 	if (!*has_inflight) {
3152 		free(inflight_counter);
3153 	}
3154 
3155 	return 0;
3156 }
3157 
3158 static void nvmf_rdma_handle_device_removal(struct spdk_nvmf_rdma_transport *rtransport,
3159 		struct spdk_nvmf_rdma_device *device);
3160 
3161 static struct spdk_nvmf_rdma_device *
3162 nvmf_rdma_find_ib_device(struct spdk_nvmf_rdma_transport *rtransport,
3163 			 struct ibv_context *context)
3164 {
3165 	struct spdk_nvmf_rdma_device	*device, *tmp_device;
3166 
3167 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp_device) {
3168 		if (device->need_destroy) {
3169 			continue;
3170 		}
3171 
3172 		if (strcmp(device->context->device->dev_name, context->device->dev_name) == 0) {
3173 			return device;
3174 		}
3175 	}
3176 
3177 	return NULL;
3178 }
3179 
3180 static bool
3181 nvmf_rdma_check_devices_context(struct spdk_nvmf_rdma_transport *rtransport,
3182 				struct ibv_context *context)
3183 {
3184 	struct spdk_nvmf_rdma_device	*old_device, *new_device;
3185 	int				rc = 0;
3186 	bool				has_inflight;
3187 
3188 	old_device = nvmf_rdma_find_ib_device(rtransport, context);
3189 
3190 	if (old_device) {
3191 		if (old_device->context != context && !old_device->need_destroy && old_device->is_ready) {
3192 			/* context may not have time to be cleaned when rescan. exactly one context
3193 			 * is valid for a device so this context must be invalid and just remove it. */
3194 			SPDK_WARNLOG("Device %p has a invalid context %p\n", old_device, old_device->context);
3195 			old_device->need_destroy = true;
3196 			nvmf_rdma_handle_device_removal(rtransport, old_device);
3197 		}
3198 		return false;
3199 	}
3200 
3201 	rc = create_ib_device(rtransport, context, &new_device);
3202 	/* TODO: update transport opts. */
3203 	if (rc < 0) {
3204 		SPDK_ERRLOG("Failed to create ib device for context: %s(%p)\n",
3205 			    ibv_get_device_name(context->device), context);
3206 		return false;
3207 	}
3208 
3209 	rc = nvmf_rdma_manage_poller(rtransport, new_device, &has_inflight, true);
3210 	if (rc < 0) {
3211 		SPDK_ERRLOG("Failed to add poller for device context: %s(%p)\n",
3212 			    ibv_get_device_name(context->device), context);
3213 		return false;
3214 	}
3215 
3216 	if (has_inflight) {
3217 		new_device->is_ready = true;
3218 	}
3219 
3220 	return true;
3221 }
3222 
3223 static bool
3224 nvmf_rdma_rescan_devices(struct spdk_nvmf_rdma_transport *rtransport)
3225 {
3226 	struct spdk_nvmf_rdma_device	*device;
3227 	struct ibv_device		**ibv_device_list = NULL;
3228 	struct ibv_context		**contexts = NULL;
3229 	int				i = 0;
3230 	int				num_dev = 0;
3231 	bool				new_create = false, has_new_device = false;
3232 	struct ibv_context		*tmp_verbs = NULL;
3233 
3234 	/* do not rescan when any device is destroying, or context may be freed when
3235 	 * regenerating the poll fds.
3236 	 */
3237 	TAILQ_FOREACH(device, &rtransport->devices, link) {
3238 		if (device->need_destroy) {
3239 			return false;
3240 		}
3241 	}
3242 
3243 	ibv_device_list = ibv_get_device_list(&num_dev);
3244 
3245 	/* There is a bug in librdmacm. If verbs init failed in rdma_get_devices, it'll be
3246 	 * marked as dead verbs and never be init again. So we need to make sure the
3247 	 * verbs is available before we call rdma_get_devices. */
3248 	if (num_dev >= 0) {
3249 		for (i = 0; i < num_dev; i++) {
3250 			tmp_verbs = ibv_open_device(ibv_device_list[i]);
3251 			if (!tmp_verbs) {
3252 				SPDK_WARNLOG("Failed to init ibv device %p, err %d. Skip rescan.\n", ibv_device_list[i], errno);
3253 				break;
3254 			}
3255 			if (nvmf_rdma_find_ib_device(rtransport, tmp_verbs) == NULL) {
3256 				SPDK_DEBUGLOG(rdma, "Find new verbs init ibv device %p(%s).\n", ibv_device_list[i],
3257 					      tmp_verbs->device->dev_name);
3258 				has_new_device = true;
3259 			}
3260 			ibv_close_device(tmp_verbs);
3261 		}
3262 		ibv_free_device_list(ibv_device_list);
3263 		if (!tmp_verbs || !has_new_device) {
3264 			return false;
3265 		}
3266 	}
3267 
3268 	contexts = rdma_get_devices(NULL);
3269 
3270 	for (i = 0; contexts && contexts[i] != NULL; i++) {
3271 		new_create |= nvmf_rdma_check_devices_context(rtransport, contexts[i]);
3272 	}
3273 
3274 	if (new_create) {
3275 		free_poll_fds(rtransport);
3276 		generate_poll_fds(rtransport);
3277 	}
3278 
3279 	if (contexts) {
3280 		rdma_free_devices(contexts);
3281 	}
3282 
3283 	return new_create;
3284 }
3285 
3286 static bool
3287 nvmf_rdma_retry_listen_port(struct spdk_nvmf_rdma_transport *rtransport)
3288 {
3289 	struct spdk_nvmf_rdma_port	*port, *tmp_port;
3290 	int				rc = 0;
3291 	bool				new_create = false;
3292 
3293 	if (TAILQ_EMPTY(&rtransport->retry_ports)) {
3294 		return false;
3295 	}
3296 
3297 	new_create = nvmf_rdma_rescan_devices(rtransport);
3298 
3299 	TAILQ_FOREACH_SAFE(port, &rtransport->retry_ports, link, tmp_port) {
3300 		rc = nvmf_rdma_listen(&rtransport->transport, port->trid, NULL);
3301 
3302 		TAILQ_REMOVE(&rtransport->retry_ports, port, link);
3303 		if (rc) {
3304 			if (new_create) {
3305 				SPDK_ERRLOG("Found new IB device but port %s:%s is still failed(%d) to listen.\n",
3306 					    port->trid->traddr, port->trid->trsvcid, rc);
3307 			}
3308 			TAILQ_INSERT_TAIL(&rtransport->retry_ports, port, link);
3309 			break;
3310 		} else {
3311 			SPDK_NOTICELOG("Port %s:%s come back\n", port->trid->traddr, port->trid->trsvcid);
3312 			free(port);
3313 		}
3314 	}
3315 
3316 	return true;
3317 }
3318 
3319 static void
3320 nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
3321 				struct spdk_nvmf_rdma_qpair *rqpair, bool drain)
3322 {
3323 	struct spdk_nvmf_request *req, *tmp;
3324 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
3325 	struct spdk_nvmf_rdma_resources *resources;
3326 
3327 	/* First process requests which are waiting for response to be sent */
3328 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_send_queue, state_link, req_tmp) {
3329 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
3330 			break;
3331 		}
3332 	}
3333 
3334 	/* We process I/O in the data transfer pending queue at the highest priority. */
3335 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_read_queue, state_link, req_tmp) {
3336 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
3337 			break;
3338 		}
3339 	}
3340 
3341 	/* Then RDMA writes since reads have stronger restrictions than writes */
3342 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_write_queue, state_link, req_tmp) {
3343 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
3344 			break;
3345 		}
3346 	}
3347 
3348 	/* Then we handle request waiting on memory buffers. */
3349 	STAILQ_FOREACH_SAFE(req, &rqpair->poller->group->group.pending_buf_queue, buf_link, tmp) {
3350 		rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
3351 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
3352 			break;
3353 		}
3354 	}
3355 
3356 	resources = rqpair->resources;
3357 	while (!STAILQ_EMPTY(&resources->free_queue) && !STAILQ_EMPTY(&resources->incoming_queue)) {
3358 		rdma_req = STAILQ_FIRST(&resources->free_queue);
3359 		STAILQ_REMOVE_HEAD(&resources->free_queue, state_link);
3360 		rdma_req->recv = STAILQ_FIRST(&resources->incoming_queue);
3361 		STAILQ_REMOVE_HEAD(&resources->incoming_queue, link);
3362 
3363 		if (rqpair->srq != NULL) {
3364 			rdma_req->req.qpair = &rdma_req->recv->qpair->qpair;
3365 			rdma_req->recv->qpair->qd++;
3366 		} else {
3367 			rqpair->qd++;
3368 		}
3369 
3370 		rdma_req->receive_tsc = rdma_req->recv->receive_tsc;
3371 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
3372 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false) {
3373 			break;
3374 		}
3375 	}
3376 	if (!STAILQ_EMPTY(&resources->incoming_queue) && STAILQ_EMPTY(&resources->free_queue)) {
3377 		rqpair->poller->stat.pending_free_request++;
3378 	}
3379 }
3380 
3381 static void
3382 nvmf_rdma_poller_process_pending_buf_queue(struct spdk_nvmf_rdma_transport *rtransport,
3383 		struct spdk_nvmf_rdma_poller *rpoller)
3384 {
3385 	struct spdk_nvmf_request *req, *tmp;
3386 	struct spdk_nvmf_rdma_request *rdma_req;
3387 
3388 	STAILQ_FOREACH_SAFE(req, &rpoller->group->group.pending_buf_queue, buf_link, tmp) {
3389 		rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
3390 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false) {
3391 			break;
3392 		}
3393 	}
3394 }
3395 
3396 static inline bool
3397 nvmf_rdma_can_ignore_last_wqe_reached(struct spdk_nvmf_rdma_device *device)
3398 {
3399 	/* iWARP transport and SoftRoCE driver don't support LAST_WQE_REACHED ibv async event */
3400 	return nvmf_rdma_is_rxe_device(device) ||
3401 	       device->context->device->transport_type == IBV_TRANSPORT_IWARP;
3402 }
3403 
3404 static void
3405 nvmf_rdma_destroy_drained_qpair(struct spdk_nvmf_rdma_qpair *rqpair)
3406 {
3407 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
3408 			struct spdk_nvmf_rdma_transport, transport);
3409 
3410 	nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
3411 
3412 	/* nvmf_rdma_close_qpair is not called */
3413 	if (!rqpair->to_close) {
3414 		return;
3415 	}
3416 
3417 	/* device is already destroyed and we should force destroy this qpair. */
3418 	if (rqpair->poller && rqpair->poller->need_destroy) {
3419 		nvmf_rdma_qpair_destroy(rqpair);
3420 		return;
3421 	}
3422 
3423 	/* In non SRQ path, we will reach rqpair->max_queue_depth. In SRQ path, we will get the last_wqe event. */
3424 	if (rqpair->current_send_depth != 0) {
3425 		return;
3426 	}
3427 
3428 	if (rqpair->srq == NULL && rqpair->current_recv_depth != rqpair->max_queue_depth) {
3429 		return;
3430 	}
3431 
3432 	if (rqpair->srq != NULL && rqpair->last_wqe_reached == false &&
3433 	    !nvmf_rdma_can_ignore_last_wqe_reached(rqpair->device)) {
3434 		return;
3435 	}
3436 
3437 	assert(rqpair->qpair.state == SPDK_NVMF_QPAIR_ERROR);
3438 
3439 	nvmf_rdma_qpair_destroy(rqpair);
3440 }
3441 
3442 static int
3443 nvmf_rdma_disconnect(struct rdma_cm_event *evt, bool *event_acked)
3444 {
3445 	struct spdk_nvmf_qpair		*qpair;
3446 	struct spdk_nvmf_rdma_qpair	*rqpair;
3447 
3448 	if (evt->id == NULL) {
3449 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
3450 		return -1;
3451 	}
3452 
3453 	qpair = evt->id->context;
3454 	if (qpair == NULL) {
3455 		SPDK_ERRLOG("disconnect request: no active connection\n");
3456 		return -1;
3457 	}
3458 
3459 	rdma_ack_cm_event(evt);
3460 	*event_acked = true;
3461 
3462 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3463 
3464 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair);
3465 
3466 	spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3467 
3468 	return 0;
3469 }
3470 
3471 #ifdef DEBUG
3472 static const char *CM_EVENT_STR[] = {
3473 	"RDMA_CM_EVENT_ADDR_RESOLVED",
3474 	"RDMA_CM_EVENT_ADDR_ERROR",
3475 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
3476 	"RDMA_CM_EVENT_ROUTE_ERROR",
3477 	"RDMA_CM_EVENT_CONNECT_REQUEST",
3478 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
3479 	"RDMA_CM_EVENT_CONNECT_ERROR",
3480 	"RDMA_CM_EVENT_UNREACHABLE",
3481 	"RDMA_CM_EVENT_REJECTED",
3482 	"RDMA_CM_EVENT_ESTABLISHED",
3483 	"RDMA_CM_EVENT_DISCONNECTED",
3484 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
3485 	"RDMA_CM_EVENT_MULTICAST_JOIN",
3486 	"RDMA_CM_EVENT_MULTICAST_ERROR",
3487 	"RDMA_CM_EVENT_ADDR_CHANGE",
3488 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
3489 };
3490 #endif /* DEBUG */
3491 
3492 static void
3493 nvmf_rdma_disconnect_qpairs_on_port(struct spdk_nvmf_rdma_transport *rtransport,
3494 				    struct spdk_nvmf_rdma_port *port)
3495 {
3496 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3497 	struct spdk_nvmf_rdma_poller		*rpoller;
3498 	struct spdk_nvmf_rdma_qpair		*rqpair;
3499 
3500 	TAILQ_FOREACH(rgroup, &rtransport->poll_groups, link) {
3501 		TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3502 			RB_FOREACH(rqpair, qpairs_tree, &rpoller->qpairs) {
3503 				if (rqpair->listen_id == port->id) {
3504 					spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3505 				}
3506 			}
3507 		}
3508 	}
3509 }
3510 
3511 static bool
3512 nvmf_rdma_handle_cm_event_addr_change(struct spdk_nvmf_transport *transport,
3513 				      struct rdma_cm_event *event)
3514 {
3515 	const struct spdk_nvme_transport_id	*trid;
3516 	struct spdk_nvmf_rdma_port		*port;
3517 	struct spdk_nvmf_rdma_transport		*rtransport;
3518 	bool					event_acked = false;
3519 
3520 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3521 	TAILQ_FOREACH(port, &rtransport->ports, link) {
3522 		if (port->id == event->id) {
3523 			SPDK_ERRLOG("ADDR_CHANGE: IP %s:%s migrated\n", port->trid->traddr, port->trid->trsvcid);
3524 			rdma_ack_cm_event(event);
3525 			event_acked = true;
3526 			trid = port->trid;
3527 			break;
3528 		}
3529 	}
3530 
3531 	if (event_acked) {
3532 		nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
3533 
3534 		nvmf_rdma_stop_listen(transport, trid);
3535 		nvmf_rdma_listen(transport, trid, NULL);
3536 	}
3537 
3538 	return event_acked;
3539 }
3540 
3541 static void
3542 nvmf_rdma_handle_device_removal(struct spdk_nvmf_rdma_transport *rtransport,
3543 				struct spdk_nvmf_rdma_device *device)
3544 {
3545 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
3546 	int				rc;
3547 	bool				has_inflight;
3548 
3549 	rc = nvmf_rdma_manage_poller(rtransport, device, &has_inflight, false);
3550 	if (rc) {
3551 		SPDK_ERRLOG("Failed to handle device removal, rc %d\n", rc);
3552 		return;
3553 	}
3554 
3555 	if (!has_inflight) {
3556 		/* no pollers, destroy the device */
3557 		device->ready_to_destroy = true;
3558 		spdk_thread_send_msg(spdk_get_thread(), _nvmf_rdma_remove_destroyed_device, rtransport);
3559 	}
3560 
3561 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
3562 		if (port->device == device) {
3563 			SPDK_NOTICELOG("Port %s:%s on device %s is being removed.\n",
3564 				       port->trid->traddr,
3565 				       port->trid->trsvcid,
3566 				       ibv_get_device_name(port->device->context->device));
3567 
3568 			/* keep NVMF listener and only destroy structures of the
3569 			 * RDMA transport. when the device comes back we can retry listening
3570 			 * and the application's workflow will not be interrupted.
3571 			 */
3572 			nvmf_rdma_stop_listen_ex(&rtransport->transport, port->trid, true);
3573 		}
3574 	}
3575 }
3576 
3577 static void
3578 nvmf_rdma_handle_cm_event_port_removal(struct spdk_nvmf_transport *transport,
3579 				       struct rdma_cm_event *event)
3580 {
3581 	struct spdk_nvmf_rdma_port		*port, *tmp_port;
3582 	struct spdk_nvmf_rdma_transport		*rtransport;
3583 
3584 	port = event->id->context;
3585 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3586 
3587 	rdma_ack_cm_event(event);
3588 
3589 	/* if device removal happens during ctrl qpair disconnecting, it's possible that we receive
3590 	 * an DEVICE_REMOVAL event on qpair but the id->qp is just NULL. So we should make sure that
3591 	 * we are handling a port event here.
3592 	 */
3593 	TAILQ_FOREACH(tmp_port, &rtransport->ports, link) {
3594 		if (port == tmp_port && port->device && !port->device->need_destroy) {
3595 			port->device->need_destroy = true;
3596 			nvmf_rdma_handle_device_removal(rtransport, port->device);
3597 		}
3598 	}
3599 }
3600 
3601 static void
3602 nvmf_process_cm_events(struct spdk_nvmf_transport *transport, uint32_t max_events)
3603 {
3604 	struct spdk_nvmf_rdma_transport *rtransport;
3605 	struct rdma_cm_event		*event;
3606 	uint32_t			i;
3607 	int				rc;
3608 	bool				event_acked;
3609 
3610 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3611 
3612 	if (rtransport->event_channel == NULL) {
3613 		return;
3614 	}
3615 
3616 	for (i = 0; i < max_events; i++) {
3617 		event_acked = false;
3618 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
3619 		if (rc) {
3620 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
3621 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
3622 			}
3623 			break;
3624 		}
3625 
3626 		SPDK_DEBUGLOG(rdma, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
3627 
3628 		spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
3629 
3630 		switch (event->event) {
3631 		case RDMA_CM_EVENT_ADDR_RESOLVED:
3632 		case RDMA_CM_EVENT_ADDR_ERROR:
3633 		case RDMA_CM_EVENT_ROUTE_RESOLVED:
3634 		case RDMA_CM_EVENT_ROUTE_ERROR:
3635 			/* No action required. The target never attempts to resolve routes. */
3636 			break;
3637 		case RDMA_CM_EVENT_CONNECT_REQUEST:
3638 			rc = nvmf_rdma_connect(transport, event);
3639 			if (rc < 0) {
3640 				SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
3641 				break;
3642 			}
3643 			break;
3644 		case RDMA_CM_EVENT_CONNECT_RESPONSE:
3645 			/* The target never initiates a new connection. So this will not occur. */
3646 			break;
3647 		case RDMA_CM_EVENT_CONNECT_ERROR:
3648 			/* Can this happen? The docs say it can, but not sure what causes it. */
3649 			break;
3650 		case RDMA_CM_EVENT_UNREACHABLE:
3651 		case RDMA_CM_EVENT_REJECTED:
3652 			/* These only occur on the client side. */
3653 			break;
3654 		case RDMA_CM_EVENT_ESTABLISHED:
3655 			/* TODO: Should we be waiting for this event anywhere? */
3656 			break;
3657 		case RDMA_CM_EVENT_DISCONNECTED:
3658 			rc = nvmf_rdma_disconnect(event, &event_acked);
3659 			if (rc < 0) {
3660 				SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
3661 				break;
3662 			}
3663 			break;
3664 		case RDMA_CM_EVENT_DEVICE_REMOVAL:
3665 			/* In case of device removal, kernel IB part triggers IBV_EVENT_DEVICE_FATAL
3666 			 * which triggers RDMA_CM_EVENT_DEVICE_REMOVAL on all cma_id’s.
3667 			 * Once these events are sent to SPDK, we should release all IB resources and
3668 			 * don't make attempts to call any ibv_query/modify/create functions. We can only call
3669 			 * ibv_destroy* functions to release user space memory allocated by IB. All kernel
3670 			 * resources are already cleaned. */
3671 			if (event->id->qp) {
3672 				/* If rdma_cm event has a valid `qp` pointer then the event refers to the
3673 				 * corresponding qpair. Otherwise the event refers to a listening device. */
3674 				rc = nvmf_rdma_disconnect(event, &event_acked);
3675 				if (rc < 0) {
3676 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
3677 					break;
3678 				}
3679 			} else {
3680 				nvmf_rdma_handle_cm_event_port_removal(transport, event);
3681 				event_acked = true;
3682 			}
3683 			break;
3684 		case RDMA_CM_EVENT_MULTICAST_JOIN:
3685 		case RDMA_CM_EVENT_MULTICAST_ERROR:
3686 			/* Multicast is not used */
3687 			break;
3688 		case RDMA_CM_EVENT_ADDR_CHANGE:
3689 			event_acked = nvmf_rdma_handle_cm_event_addr_change(transport, event);
3690 			break;
3691 		case RDMA_CM_EVENT_TIMEWAIT_EXIT:
3692 			/* For now, do nothing. The target never re-uses queue pairs. */
3693 			break;
3694 		default:
3695 			SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
3696 			break;
3697 		}
3698 		if (!event_acked) {
3699 			rdma_ack_cm_event(event);
3700 		}
3701 	}
3702 }
3703 
3704 static void
3705 nvmf_rdma_handle_last_wqe_reached(struct spdk_nvmf_rdma_qpair *rqpair)
3706 {
3707 	rqpair->last_wqe_reached = true;
3708 	nvmf_rdma_destroy_drained_qpair(rqpair);
3709 }
3710 
3711 static void
3712 nvmf_rdma_qpair_process_ibv_event(void *ctx)
3713 {
3714 	struct spdk_nvmf_rdma_ibv_event_ctx *event_ctx = ctx;
3715 
3716 	if (event_ctx->rqpair) {
3717 		STAILQ_REMOVE(&event_ctx->rqpair->ibv_events, event_ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3718 		if (event_ctx->cb_fn) {
3719 			event_ctx->cb_fn(event_ctx->rqpair);
3720 		}
3721 	}
3722 	free(event_ctx);
3723 }
3724 
3725 static int
3726 nvmf_rdma_send_qpair_async_event(struct spdk_nvmf_rdma_qpair *rqpair,
3727 				 spdk_nvmf_rdma_qpair_ibv_event fn)
3728 {
3729 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx;
3730 	struct spdk_thread *thr = NULL;
3731 	int rc;
3732 
3733 	if (rqpair->qpair.group) {
3734 		thr = rqpair->qpair.group->thread;
3735 	} else if (rqpair->destruct_channel) {
3736 		thr = spdk_io_channel_get_thread(rqpair->destruct_channel);
3737 	}
3738 
3739 	if (!thr) {
3740 		SPDK_DEBUGLOG(rdma, "rqpair %p has no thread\n", rqpair);
3741 		return -EINVAL;
3742 	}
3743 
3744 	ctx = calloc(1, sizeof(*ctx));
3745 	if (!ctx) {
3746 		return -ENOMEM;
3747 	}
3748 
3749 	ctx->rqpair = rqpair;
3750 	ctx->cb_fn = fn;
3751 	STAILQ_INSERT_TAIL(&rqpair->ibv_events, ctx, link);
3752 
3753 	rc = spdk_thread_send_msg(thr, nvmf_rdma_qpair_process_ibv_event, ctx);
3754 	if (rc) {
3755 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3756 		free(ctx);
3757 	}
3758 
3759 	return rc;
3760 }
3761 
3762 static int
3763 nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
3764 {
3765 	int				rc;
3766 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
3767 	struct ibv_async_event		event;
3768 
3769 	rc = ibv_get_async_event(device->context, &event);
3770 
3771 	if (rc) {
3772 		/* In non-blocking mode -1 means there are no events available */
3773 		return rc;
3774 	}
3775 
3776 	switch (event.event_type) {
3777 	case IBV_EVENT_QP_FATAL:
3778 	case IBV_EVENT_QP_LAST_WQE_REACHED:
3779 	case IBV_EVENT_QP_REQ_ERR:
3780 	case IBV_EVENT_QP_ACCESS_ERR:
3781 	case IBV_EVENT_COMM_EST:
3782 	case IBV_EVENT_PATH_MIG:
3783 	case IBV_EVENT_PATH_MIG_ERR:
3784 		rqpair = event.element.qp->qp_context;
3785 		if (!rqpair) {
3786 			/* Any QP event for NVMe-RDMA initiator may be returned. */
3787 			SPDK_NOTICELOG("Async QP event for unknown QP: %s\n",
3788 				       ibv_event_type_str(event.event_type));
3789 			break;
3790 		}
3791 
3792 		switch (event.event_type) {
3793 		case IBV_EVENT_QP_FATAL:
3794 			SPDK_ERRLOG("Fatal event received for rqpair %p\n", rqpair);
3795 			spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3796 					  (uintptr_t)rqpair, event.event_type);
3797 			rqpair->ibv_in_error_state = true;
3798 			spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
3799 			break;
3800 		case IBV_EVENT_QP_LAST_WQE_REACHED:
3801 			/* This event only occurs for shared receive queues. */
3802 			SPDK_DEBUGLOG(rdma, "Last WQE reached event received for rqpair %p\n", rqpair);
3803 			rc = nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_last_wqe_reached);
3804 			if (rc) {
3805 				SPDK_WARNLOG("Failed to send LAST_WQE_REACHED event. rqpair %p, err %d\n", rqpair, rc);
3806 				rqpair->last_wqe_reached = true;
3807 			}
3808 			break;
3809 		case IBV_EVENT_QP_REQ_ERR:
3810 		case IBV_EVENT_QP_ACCESS_ERR:
3811 		case IBV_EVENT_COMM_EST:
3812 		case IBV_EVENT_PATH_MIG:
3813 		case IBV_EVENT_PATH_MIG_ERR:
3814 			SPDK_NOTICELOG("Async QP event: %s\n",
3815 				       ibv_event_type_str(event.event_type));
3816 			spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3817 					  (uintptr_t)rqpair, event.event_type);
3818 			rqpair->ibv_in_error_state = true;
3819 			break;
3820 		default:
3821 			break;
3822 		}
3823 		break;
3824 	case IBV_EVENT_DEVICE_FATAL:
3825 		SPDK_ERRLOG("Device Fatal event[%s] received on %s. device: %p\n",
3826 			    ibv_event_type_str(event.event_type), ibv_get_device_name(device->context->device), device);
3827 		device->need_destroy = true;
3828 		break;
3829 	case IBV_EVENT_CQ_ERR:
3830 	case IBV_EVENT_PORT_ACTIVE:
3831 	case IBV_EVENT_PORT_ERR:
3832 	case IBV_EVENT_LID_CHANGE:
3833 	case IBV_EVENT_PKEY_CHANGE:
3834 	case IBV_EVENT_SM_CHANGE:
3835 	case IBV_EVENT_SRQ_ERR:
3836 	case IBV_EVENT_SRQ_LIMIT_REACHED:
3837 	case IBV_EVENT_CLIENT_REREGISTER:
3838 	case IBV_EVENT_GID_CHANGE:
3839 	case IBV_EVENT_SQ_DRAINED:
3840 	default:
3841 		SPDK_NOTICELOG("Async event: %s\n",
3842 			       ibv_event_type_str(event.event_type));
3843 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
3844 		break;
3845 	}
3846 	ibv_ack_async_event(&event);
3847 
3848 	return 0;
3849 }
3850 
3851 static void
3852 nvmf_process_ib_events(struct spdk_nvmf_rdma_device *device, uint32_t max_events)
3853 {
3854 	int rc = 0;
3855 	uint32_t i = 0;
3856 
3857 	for (i = 0; i < max_events; i++) {
3858 		rc = nvmf_process_ib_event(device);
3859 		if (rc) {
3860 			break;
3861 		}
3862 	}
3863 
3864 	SPDK_DEBUGLOG(rdma, "Device %s: %u events processed\n", device->context->device->name, i);
3865 }
3866 
3867 static int
3868 nvmf_rdma_accept(void *ctx)
3869 {
3870 	int	nfds, i = 0;
3871 	struct spdk_nvmf_transport *transport = ctx;
3872 	struct spdk_nvmf_rdma_transport *rtransport;
3873 	struct spdk_nvmf_rdma_device *device, *tmp;
3874 	uint32_t count;
3875 	short revents;
3876 	bool do_retry;
3877 
3878 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3879 	do_retry = nvmf_rdma_retry_listen_port(rtransport);
3880 
3881 	count = nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
3882 
3883 	if (nfds <= 0) {
3884 		return do_retry ? SPDK_POLLER_BUSY : SPDK_POLLER_IDLE;
3885 	}
3886 
3887 	/* The first poll descriptor is RDMA CM event */
3888 	if (rtransport->poll_fds[i++].revents & POLLIN) {
3889 		nvmf_process_cm_events(transport, NVMF_RDMA_MAX_EVENTS_PER_POLL);
3890 		nfds--;
3891 	}
3892 
3893 	if (nfds == 0) {
3894 		return SPDK_POLLER_BUSY;
3895 	}
3896 
3897 	/* Second and subsequent poll descriptors are IB async events */
3898 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
3899 		revents = rtransport->poll_fds[i++].revents;
3900 		if (revents & POLLIN) {
3901 			if (spdk_likely(!device->need_destroy)) {
3902 				nvmf_process_ib_events(device, NVMF_RDMA_MAX_EVENTS_PER_POLL);
3903 				if (spdk_unlikely(device->need_destroy)) {
3904 					nvmf_rdma_handle_device_removal(rtransport, device);
3905 				}
3906 			}
3907 			nfds--;
3908 		} else if (revents & POLLNVAL || revents & POLLHUP) {
3909 			SPDK_ERRLOG("Receive unknown revent %x on device %p\n", (int)revents, device);
3910 			nfds--;
3911 		}
3912 	}
3913 	/* check all flagged fd's have been served */
3914 	assert(nfds == 0);
3915 
3916 	return count > 0 ? SPDK_POLLER_BUSY : SPDK_POLLER_IDLE;
3917 }
3918 
3919 static void
3920 nvmf_rdma_cdata_init(struct spdk_nvmf_transport *transport, struct spdk_nvmf_subsystem *subsystem,
3921 		     struct spdk_nvmf_ctrlr_data *cdata)
3922 {
3923 	cdata->nvmf_specific.msdbd = NVMF_DEFAULT_MSDBD;
3924 
3925 	/* Disable in-capsule data transfer for RDMA controller when dif_insert_or_strip is enabled
3926 	since in-capsule data only works with NVME drives that support SGL memory layout */
3927 	if (transport->opts.dif_insert_or_strip) {
3928 		cdata->nvmf_specific.ioccsz = sizeof(struct spdk_nvme_cmd) / 16;
3929 	}
3930 
3931 	if (cdata->nvmf_specific.ioccsz > ((sizeof(struct spdk_nvme_cmd) + 0x1000) / 16)) {
3932 		SPDK_WARNLOG("RDMA is configured to support up to 16 SGL entries while in capsule"
3933 			     " data is greater than 4KiB.\n");
3934 		SPDK_WARNLOG("When used in conjunction with the NVMe-oF initiator from the Linux "
3935 			     "kernel between versions 5.4 and 5.12 data corruption may occur for "
3936 			     "writes that are not a multiple of 4KiB in size.\n");
3937 	}
3938 }
3939 
3940 static void
3941 nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
3942 		   struct spdk_nvme_transport_id *trid,
3943 		   struct spdk_nvmf_discovery_log_page_entry *entry)
3944 {
3945 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
3946 	entry->adrfam = trid->adrfam;
3947 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
3948 
3949 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
3950 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
3951 
3952 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
3953 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
3954 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
3955 }
3956 
3957 static int
3958 nvmf_rdma_poller_create(struct spdk_nvmf_rdma_transport *rtransport,
3959 			struct spdk_nvmf_rdma_poll_group *rgroup, struct spdk_nvmf_rdma_device *device,
3960 			struct spdk_nvmf_rdma_poller **out_poller)
3961 {
3962 	struct spdk_nvmf_rdma_poller		*poller;
3963 	struct spdk_rdma_srq_init_attr		srq_init_attr;
3964 	struct spdk_nvmf_rdma_resource_opts	opts;
3965 	int					num_cqe;
3966 
3967 	poller = calloc(1, sizeof(*poller));
3968 	if (!poller) {
3969 		SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
3970 		return -1;
3971 	}
3972 
3973 	poller->device = device;
3974 	poller->group = rgroup;
3975 	*out_poller = poller;
3976 
3977 	RB_INIT(&poller->qpairs);
3978 	STAILQ_INIT(&poller->qpairs_pending_send);
3979 	STAILQ_INIT(&poller->qpairs_pending_recv);
3980 
3981 	TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
3982 	SPDK_DEBUGLOG(rdma, "Create poller %p on device %p in poll group %p.\n", poller, device, rgroup);
3983 	if (rtransport->rdma_opts.no_srq == false && device->num_srq < device->attr.max_srq) {
3984 		if ((int)rtransport->rdma_opts.max_srq_depth > device->attr.max_srq_wr) {
3985 			SPDK_WARNLOG("Requested SRQ depth %u, max supported by dev %s is %d\n",
3986 				     rtransport->rdma_opts.max_srq_depth, device->context->device->name, device->attr.max_srq_wr);
3987 		}
3988 		poller->max_srq_depth = spdk_min((int)rtransport->rdma_opts.max_srq_depth, device->attr.max_srq_wr);
3989 
3990 		device->num_srq++;
3991 		memset(&srq_init_attr, 0, sizeof(srq_init_attr));
3992 		srq_init_attr.pd = device->pd;
3993 		srq_init_attr.stats = &poller->stat.qp_stats.recv;
3994 		srq_init_attr.srq_init_attr.attr.max_wr = poller->max_srq_depth;
3995 		srq_init_attr.srq_init_attr.attr.max_sge = spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
3996 		poller->srq = spdk_rdma_srq_create(&srq_init_attr);
3997 		if (!poller->srq) {
3998 			SPDK_ERRLOG("Unable to create shared receive queue, errno %d\n", errno);
3999 			return -1;
4000 		}
4001 
4002 		opts.qp = poller->srq;
4003 		opts.map = device->map;
4004 		opts.qpair = NULL;
4005 		opts.shared = true;
4006 		opts.max_queue_depth = poller->max_srq_depth;
4007 		opts.in_capsule_data_size = rtransport->transport.opts.in_capsule_data_size;
4008 
4009 		poller->resources = nvmf_rdma_resources_create(&opts);
4010 		if (!poller->resources) {
4011 			SPDK_ERRLOG("Unable to allocate resources for shared receive queue.\n");
4012 			return -1;
4013 		}
4014 	}
4015 
4016 	/*
4017 	 * When using an srq, we can limit the completion queue at startup.
4018 	 * The following formula represents the calculation:
4019 	 * num_cqe = num_recv + num_data_wr + num_send_wr.
4020 	 * where num_recv=num_data_wr=and num_send_wr=poller->max_srq_depth
4021 	 */
4022 	if (poller->srq) {
4023 		num_cqe = poller->max_srq_depth * 3;
4024 	} else {
4025 		num_cqe = rtransport->rdma_opts.num_cqe;
4026 	}
4027 
4028 	poller->cq = ibv_create_cq(device->context, num_cqe, poller, NULL, 0);
4029 	if (!poller->cq) {
4030 		SPDK_ERRLOG("Unable to create completion queue\n");
4031 		return -1;
4032 	}
4033 	poller->num_cqe = num_cqe;
4034 	return 0;
4035 }
4036 
4037 static void
4038 _nvmf_rdma_register_poller_in_group(void *c)
4039 {
4040 	struct spdk_nvmf_rdma_poller	*poller;
4041 	struct poller_manage_ctx	*ctx = c;
4042 	struct spdk_nvmf_rdma_device	*device;
4043 	int				rc;
4044 
4045 	rc = nvmf_rdma_poller_create(ctx->rtransport, ctx->rgroup, ctx->device, &poller);
4046 	if (rc < 0 && poller) {
4047 		nvmf_rdma_poller_destroy(poller);
4048 	}
4049 
4050 	device = ctx->device;
4051 	if (nvmf_rdma_all_pollers_management_done(ctx)) {
4052 		device->is_ready = true;
4053 	}
4054 }
4055 
4056 static void nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
4057 
4058 static struct spdk_nvmf_transport_poll_group *
4059 nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport,
4060 			    struct spdk_nvmf_poll_group *group)
4061 {
4062 	struct spdk_nvmf_rdma_transport		*rtransport;
4063 	struct spdk_nvmf_rdma_poll_group	*rgroup;
4064 	struct spdk_nvmf_rdma_poller		*poller;
4065 	struct spdk_nvmf_rdma_device		*device;
4066 	int					rc;
4067 
4068 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
4069 
4070 	rgroup = calloc(1, sizeof(*rgroup));
4071 	if (!rgroup) {
4072 		return NULL;
4073 	}
4074 
4075 	TAILQ_INIT(&rgroup->pollers);
4076 
4077 	TAILQ_FOREACH(device, &rtransport->devices, link) {
4078 		rc = nvmf_rdma_poller_create(rtransport, rgroup, device, &poller);
4079 		if (rc < 0) {
4080 			nvmf_rdma_poll_group_destroy(&rgroup->group);
4081 			return NULL;
4082 		}
4083 	}
4084 
4085 	TAILQ_INSERT_TAIL(&rtransport->poll_groups, rgroup, link);
4086 	if (rtransport->conn_sched.next_admin_pg == NULL) {
4087 		rtransport->conn_sched.next_admin_pg = rgroup;
4088 		rtransport->conn_sched.next_io_pg = rgroup;
4089 	}
4090 
4091 	return &rgroup->group;
4092 }
4093 
4094 static uint32_t
4095 nvmf_poll_group_get_io_qpair_count(struct spdk_nvmf_poll_group *pg)
4096 {
4097 	uint32_t count;
4098 
4099 	/* Just assume that unassociated qpairs will eventually be io
4100 	 * qpairs.  This is close enough for the use cases for this
4101 	 * function.
4102 	 */
4103 	pthread_mutex_lock(&pg->mutex);
4104 	count = pg->stat.current_io_qpairs + pg->current_unassociated_qpairs;
4105 	pthread_mutex_unlock(&pg->mutex);
4106 
4107 	return count;
4108 }
4109 
4110 static struct spdk_nvmf_transport_poll_group *
4111 nvmf_rdma_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
4112 {
4113 	struct spdk_nvmf_rdma_transport *rtransport;
4114 	struct spdk_nvmf_rdma_poll_group **pg;
4115 	struct spdk_nvmf_transport_poll_group *result;
4116 	uint32_t count;
4117 
4118 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
4119 
4120 	if (TAILQ_EMPTY(&rtransport->poll_groups)) {
4121 		return NULL;
4122 	}
4123 
4124 	if (qpair->qid == 0) {
4125 		pg = &rtransport->conn_sched.next_admin_pg;
4126 	} else {
4127 		struct spdk_nvmf_rdma_poll_group *pg_min, *pg_start, *pg_current;
4128 		uint32_t min_value;
4129 
4130 		pg = &rtransport->conn_sched.next_io_pg;
4131 		pg_min = *pg;
4132 		pg_start = *pg;
4133 		pg_current = *pg;
4134 		min_value = nvmf_poll_group_get_io_qpair_count(pg_current->group.group);
4135 
4136 		while (1) {
4137 			count = nvmf_poll_group_get_io_qpair_count(pg_current->group.group);
4138 
4139 			if (count < min_value) {
4140 				min_value = count;
4141 				pg_min = pg_current;
4142 			}
4143 
4144 			pg_current = TAILQ_NEXT(pg_current, link);
4145 			if (pg_current == NULL) {
4146 				pg_current = TAILQ_FIRST(&rtransport->poll_groups);
4147 			}
4148 
4149 			if (pg_current == pg_start || min_value == 0) {
4150 				break;
4151 			}
4152 		}
4153 		*pg = pg_min;
4154 	}
4155 
4156 	assert(*pg != NULL);
4157 
4158 	result = &(*pg)->group;
4159 
4160 	*pg = TAILQ_NEXT(*pg, link);
4161 	if (*pg == NULL) {
4162 		*pg = TAILQ_FIRST(&rtransport->poll_groups);
4163 	}
4164 
4165 	return result;
4166 }
4167 
4168 static void
4169 nvmf_rdma_poller_destroy(struct spdk_nvmf_rdma_poller *poller)
4170 {
4171 	struct spdk_nvmf_rdma_qpair	*qpair, *tmp_qpair;
4172 	int				rc;
4173 
4174 	TAILQ_REMOVE(&poller->group->pollers, poller, link);
4175 	RB_FOREACH_SAFE(qpair, qpairs_tree, &poller->qpairs, tmp_qpair) {
4176 		nvmf_rdma_qpair_destroy(qpair);
4177 	}
4178 
4179 	if (poller->srq) {
4180 		if (poller->resources) {
4181 			nvmf_rdma_resources_destroy(poller->resources);
4182 		}
4183 		spdk_rdma_srq_destroy(poller->srq);
4184 		SPDK_DEBUGLOG(rdma, "Destroyed RDMA shared queue %p\n", poller->srq);
4185 	}
4186 
4187 	if (poller->cq) {
4188 		rc = ibv_destroy_cq(poller->cq);
4189 		if (rc != 0) {
4190 			SPDK_ERRLOG("Destroy cq return %d, error: %s\n", rc, strerror(errno));
4191 		}
4192 	}
4193 
4194 	if (poller->destroy_cb) {
4195 		poller->destroy_cb(poller->destroy_cb_ctx);
4196 		poller->destroy_cb = NULL;
4197 	}
4198 
4199 	free(poller);
4200 }
4201 
4202 static void
4203 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
4204 {
4205 	struct spdk_nvmf_rdma_poll_group	*rgroup, *next_rgroup;
4206 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
4207 	struct spdk_nvmf_rdma_transport		*rtransport;
4208 
4209 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
4210 	if (!rgroup) {
4211 		return;
4212 	}
4213 
4214 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
4215 		nvmf_rdma_poller_destroy(poller);
4216 	}
4217 
4218 	if (rgroup->group.transport == NULL) {
4219 		/* Transport can be NULL when nvmf_rdma_poll_group_create()
4220 		 * calls this function directly in a failure path. */
4221 		free(rgroup);
4222 		return;
4223 	}
4224 
4225 	rtransport = SPDK_CONTAINEROF(rgroup->group.transport, struct spdk_nvmf_rdma_transport, transport);
4226 
4227 	next_rgroup = TAILQ_NEXT(rgroup, link);
4228 	TAILQ_REMOVE(&rtransport->poll_groups, rgroup, link);
4229 	if (next_rgroup == NULL) {
4230 		next_rgroup = TAILQ_FIRST(&rtransport->poll_groups);
4231 	}
4232 	if (rtransport->conn_sched.next_admin_pg == rgroup) {
4233 		rtransport->conn_sched.next_admin_pg = next_rgroup;
4234 	}
4235 	if (rtransport->conn_sched.next_io_pg == rgroup) {
4236 		rtransport->conn_sched.next_io_pg = next_rgroup;
4237 	}
4238 
4239 	free(rgroup);
4240 }
4241 
4242 static void
4243 nvmf_rdma_qpair_reject_connection(struct spdk_nvmf_rdma_qpair *rqpair)
4244 {
4245 	if (rqpair->cm_id != NULL) {
4246 		nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
4247 	}
4248 }
4249 
4250 static int
4251 nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
4252 			 struct spdk_nvmf_qpair *qpair)
4253 {
4254 	struct spdk_nvmf_rdma_poll_group	*rgroup;
4255 	struct spdk_nvmf_rdma_qpair		*rqpair;
4256 	struct spdk_nvmf_rdma_device		*device;
4257 	struct spdk_nvmf_rdma_poller		*poller;
4258 	int					rc;
4259 
4260 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
4261 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4262 
4263 	device = rqpair->device;
4264 
4265 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
4266 		if (poller->device == device) {
4267 			break;
4268 		}
4269 	}
4270 
4271 	if (!poller) {
4272 		SPDK_ERRLOG("No poller found for device.\n");
4273 		return -1;
4274 	}
4275 
4276 	if (poller->need_destroy) {
4277 		SPDK_ERRLOG("Poller is destroying.\n");
4278 		return -1;
4279 	}
4280 
4281 	rqpair->poller = poller;
4282 	rqpair->srq = rqpair->poller->srq;
4283 
4284 	rc = nvmf_rdma_qpair_initialize(qpair);
4285 	if (rc < 0) {
4286 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
4287 		rqpair->poller = NULL;
4288 		rqpair->srq = NULL;
4289 		return -1;
4290 	}
4291 
4292 	RB_INSERT(qpairs_tree, &poller->qpairs, rqpair);
4293 
4294 	rc = nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
4295 	if (rc) {
4296 		/* Try to reject, but we probably can't */
4297 		nvmf_rdma_qpair_reject_connection(rqpair);
4298 		return -1;
4299 	}
4300 
4301 	return 0;
4302 }
4303 
4304 static int
4305 nvmf_rdma_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
4306 			    struct spdk_nvmf_qpair *qpair)
4307 {
4308 	struct spdk_nvmf_rdma_qpair		*rqpair;
4309 
4310 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4311 	assert(group->transport->tgt != NULL);
4312 
4313 	rqpair->destruct_channel = spdk_get_io_channel(group->transport->tgt);
4314 
4315 	if (!rqpair->destruct_channel) {
4316 		SPDK_WARNLOG("failed to get io_channel, qpair %p\n", qpair);
4317 		return 0;
4318 	}
4319 
4320 	/* Sanity check that we get io_channel on the correct thread */
4321 	if (qpair->group) {
4322 		assert(qpair->group->thread == spdk_io_channel_get_thread(rqpair->destruct_channel));
4323 	}
4324 
4325 	return 0;
4326 }
4327 
4328 static int
4329 nvmf_rdma_request_free(struct spdk_nvmf_request *req)
4330 {
4331 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
4332 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
4333 			struct spdk_nvmf_rdma_transport, transport);
4334 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
4335 					      struct spdk_nvmf_rdma_qpair, qpair);
4336 
4337 	/*
4338 	 * AER requests are freed when a qpair is destroyed. The recv corresponding to that request
4339 	 * needs to be returned to the shared receive queue or the poll group will eventually be
4340 	 * starved of RECV structures.
4341 	 */
4342 	if (rqpair->srq && rdma_req->recv) {
4343 		int rc;
4344 		struct ibv_recv_wr *bad_recv_wr;
4345 
4346 		spdk_rdma_srq_queue_recv_wrs(rqpair->srq, &rdma_req->recv->wr);
4347 		rc = spdk_rdma_srq_flush_recv_wrs(rqpair->srq, &bad_recv_wr);
4348 		if (rc) {
4349 			SPDK_ERRLOG("Unable to re-post rx descriptor\n");
4350 		}
4351 	}
4352 
4353 	_nvmf_rdma_request_free(rdma_req, rtransport);
4354 	return 0;
4355 }
4356 
4357 static int
4358 nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
4359 {
4360 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
4361 			struct spdk_nvmf_rdma_transport, transport);
4362 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
4363 			struct spdk_nvmf_rdma_request, req);
4364 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
4365 			struct spdk_nvmf_rdma_qpair, qpair);
4366 
4367 	if (spdk_unlikely(rqpair->ibv_in_error_state)) {
4368 		/* The connection is dead. Move the request directly to the completed state. */
4369 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
4370 	} else {
4371 		/* The connection is alive, so process the request as normal */
4372 		rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
4373 	}
4374 
4375 	nvmf_rdma_request_process(rtransport, rdma_req);
4376 
4377 	return 0;
4378 }
4379 
4380 static void
4381 nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair,
4382 		      spdk_nvmf_transport_qpair_fini_cb cb_fn, void *cb_arg)
4383 {
4384 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4385 
4386 	rqpair->to_close = true;
4387 
4388 	/* This happens only when the qpair is disconnected before
4389 	 * it is added to the poll group. Since there is no poll group,
4390 	 * the RDMA qp has not been initialized yet and the RDMA CM
4391 	 * event has not yet been acknowledged, so we need to reject it.
4392 	 */
4393 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
4394 		nvmf_rdma_qpair_reject_connection(rqpair);
4395 		nvmf_rdma_qpair_destroy(rqpair);
4396 		return;
4397 	}
4398 
4399 	if (rqpair->rdma_qp) {
4400 		spdk_rdma_qp_disconnect(rqpair->rdma_qp);
4401 	}
4402 
4403 	nvmf_rdma_destroy_drained_qpair(rqpair);
4404 
4405 	if (cb_fn) {
4406 		cb_fn(cb_arg);
4407 	}
4408 }
4409 
4410 static struct spdk_nvmf_rdma_qpair *
4411 get_rdma_qpair_from_wc(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_wc *wc)
4412 {
4413 	struct spdk_nvmf_rdma_qpair find;
4414 
4415 	find.qp_num = wc->qp_num;
4416 
4417 	return RB_FIND(qpairs_tree, &rpoller->qpairs, &find);
4418 }
4419 
4420 #ifdef DEBUG
4421 static int
4422 nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
4423 {
4424 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
4425 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
4426 }
4427 #endif
4428 
4429 static void
4430 _poller_reset_failed_recvs(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_recv_wr *bad_recv_wr,
4431 			   int rc)
4432 {
4433 	struct spdk_nvmf_rdma_recv	*rdma_recv;
4434 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
4435 
4436 	SPDK_ERRLOG("Failed to post a recv for the poller %p with errno %d\n", rpoller, -rc);
4437 	while (bad_recv_wr != NULL) {
4438 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_recv_wr->wr_id;
4439 		rdma_recv = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
4440 
4441 		rdma_recv->qpair->current_recv_depth++;
4442 		bad_recv_wr = bad_recv_wr->next;
4443 		SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rdma_recv->qpair, -rc);
4444 		spdk_nvmf_qpair_disconnect(&rdma_recv->qpair->qpair, NULL, NULL);
4445 	}
4446 }
4447 
4448 static void
4449 _qp_reset_failed_recvs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *bad_recv_wr, int rc)
4450 {
4451 	SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rqpair, -rc);
4452 	while (bad_recv_wr != NULL) {
4453 		bad_recv_wr = bad_recv_wr->next;
4454 		rqpair->current_recv_depth++;
4455 	}
4456 	spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
4457 }
4458 
4459 static void
4460 _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
4461 		     struct spdk_nvmf_rdma_poller *rpoller)
4462 {
4463 	struct spdk_nvmf_rdma_qpair	*rqpair;
4464 	struct ibv_recv_wr		*bad_recv_wr;
4465 	int				rc;
4466 
4467 	if (rpoller->srq) {
4468 		rc = spdk_rdma_srq_flush_recv_wrs(rpoller->srq, &bad_recv_wr);
4469 		if (spdk_unlikely(rc)) {
4470 			_poller_reset_failed_recvs(rpoller, bad_recv_wr, rc);
4471 		}
4472 	} else {
4473 		while (!STAILQ_EMPTY(&rpoller->qpairs_pending_recv)) {
4474 			rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_recv);
4475 			rc = spdk_rdma_qp_flush_recv_wrs(rqpair->rdma_qp, &bad_recv_wr);
4476 			if (spdk_unlikely(rc)) {
4477 				_qp_reset_failed_recvs(rqpair, bad_recv_wr, rc);
4478 			}
4479 			STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_recv, recv_link);
4480 		}
4481 	}
4482 }
4483 
4484 static void
4485 _qp_reset_failed_sends(struct spdk_nvmf_rdma_transport *rtransport,
4486 		       struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_send_wr *bad_wr, int rc)
4487 {
4488 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
4489 	struct spdk_nvmf_rdma_request	*prev_rdma_req = NULL, *cur_rdma_req = NULL;
4490 
4491 	SPDK_ERRLOG("Failed to post a send for the qpair %p with errno %d\n", rqpair, -rc);
4492 	for (; bad_wr != NULL; bad_wr = bad_wr->next) {
4493 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_wr->wr_id;
4494 		assert(rqpair->current_send_depth > 0);
4495 		rqpair->current_send_depth--;
4496 		switch (bad_rdma_wr->type) {
4497 		case RDMA_WR_TYPE_DATA:
4498 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, data_wr);
4499 			if (bad_wr->opcode == IBV_WR_RDMA_READ) {
4500 				assert(rqpair->current_read_depth > 0);
4501 				rqpair->current_read_depth--;
4502 			}
4503 			break;
4504 		case RDMA_WR_TYPE_SEND:
4505 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, rsp_wr);
4506 			break;
4507 		default:
4508 			SPDK_ERRLOG("Found a RECV in the list of pending SEND requests for qpair %p\n", rqpair);
4509 			prev_rdma_req = cur_rdma_req;
4510 			continue;
4511 		}
4512 
4513 		if (prev_rdma_req == cur_rdma_req) {
4514 			/* this request was handled by an earlier wr. i.e. we were performing an nvme read. */
4515 			/* We only have to check against prev_wr since each requests wrs are contiguous in this list. */
4516 			continue;
4517 		}
4518 
4519 		switch (cur_rdma_req->state) {
4520 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
4521 			cur_rdma_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
4522 			STAILQ_INSERT_TAIL(&rqpair->pending_rdma_send_queue, cur_rdma_req, state_link);
4523 			cur_rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING;
4524 			break;
4525 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
4526 		case RDMA_REQUEST_STATE_COMPLETING:
4527 			cur_rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
4528 			break;
4529 		default:
4530 			SPDK_ERRLOG("Found a request in a bad state %d when draining pending SEND requests for qpair %p\n",
4531 				    cur_rdma_req->state, rqpair);
4532 			continue;
4533 		}
4534 
4535 		nvmf_rdma_request_process(rtransport, cur_rdma_req);
4536 		prev_rdma_req = cur_rdma_req;
4537 	}
4538 
4539 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
4540 		/* Disconnect the connection. */
4541 		spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
4542 	}
4543 
4544 }
4545 
4546 static void
4547 _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
4548 		     struct spdk_nvmf_rdma_poller *rpoller)
4549 {
4550 	struct spdk_nvmf_rdma_qpair	*rqpair;
4551 	struct ibv_send_wr		*bad_wr = NULL;
4552 	int				rc;
4553 
4554 	while (!STAILQ_EMPTY(&rpoller->qpairs_pending_send)) {
4555 		rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_send);
4556 		rc = spdk_rdma_qp_flush_send_wrs(rqpair->rdma_qp, &bad_wr);
4557 
4558 		/* bad wr always points to the first wr that failed. */
4559 		if (spdk_unlikely(rc)) {
4560 			_qp_reset_failed_sends(rtransport, rqpair, bad_wr, rc);
4561 		}
4562 		STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_send, send_link);
4563 	}
4564 }
4565 
4566 static const char *
4567 nvmf_rdma_wr_type_str(enum spdk_nvmf_rdma_wr_type wr_type)
4568 {
4569 	switch (wr_type) {
4570 	case RDMA_WR_TYPE_RECV:
4571 		return "RECV";
4572 	case RDMA_WR_TYPE_SEND:
4573 		return "SEND";
4574 	case RDMA_WR_TYPE_DATA:
4575 		return "DATA";
4576 	default:
4577 		SPDK_ERRLOG("Unknown WR type %d\n", wr_type);
4578 		SPDK_UNREACHABLE();
4579 	}
4580 }
4581 
4582 static inline void
4583 nvmf_rdma_log_wc_status(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_wc *wc)
4584 {
4585 	enum spdk_nvmf_rdma_wr_type wr_type = ((struct spdk_nvmf_rdma_wr *)wc->wr_id)->type;
4586 
4587 	if (wc->status == IBV_WC_WR_FLUSH_ERR) {
4588 		/* If qpair is in ERR state, we will receive completions for all posted and not completed
4589 		 * Work Requests with IBV_WC_WR_FLUSH_ERR status. Don't log an error in that case */
4590 		SPDK_DEBUGLOG(rdma,
4591 			      "Error on CQ %p, (qp state %d, in_error %d) request 0x%lu, type %s, status: (%d): %s\n",
4592 			      rqpair->poller->cq, rqpair->qpair.state, rqpair->ibv_in_error_state, wc->wr_id,
4593 			      nvmf_rdma_wr_type_str(wr_type), wc->status, ibv_wc_status_str(wc->status));
4594 	} else {
4595 		SPDK_ERRLOG("Error on CQ %p, (qp state %d, in_error %d) request 0x%lu, type %s, status: (%d): %s\n",
4596 			    rqpair->poller->cq, rqpair->qpair.state, rqpair->ibv_in_error_state, wc->wr_id,
4597 			    nvmf_rdma_wr_type_str(wr_type), wc->status, ibv_wc_status_str(wc->status));
4598 	}
4599 }
4600 
4601 static int
4602 nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
4603 		      struct spdk_nvmf_rdma_poller *rpoller)
4604 {
4605 	struct ibv_wc wc[32];
4606 	struct spdk_nvmf_rdma_wr	*rdma_wr;
4607 	struct spdk_nvmf_rdma_request	*rdma_req;
4608 	struct spdk_nvmf_rdma_recv	*rdma_recv;
4609 	struct spdk_nvmf_rdma_qpair	*rqpair, *tmp_rqpair;
4610 	int reaped, i;
4611 	int count = 0;
4612 	int rc;
4613 	bool error = false;
4614 	uint64_t poll_tsc = spdk_get_ticks();
4615 
4616 	if (spdk_unlikely(rpoller->need_destroy)) {
4617 		/* If qpair is closed before poller destroy, nvmf_rdma_destroy_drained_qpair may not
4618 		 * be called because we cannot poll anything from cq. So we call that here to force
4619 		 * destroy the qpair after to_close turning true.
4620 		 */
4621 		RB_FOREACH_SAFE(rqpair, qpairs_tree, &rpoller->qpairs, tmp_rqpair) {
4622 			nvmf_rdma_destroy_drained_qpair(rqpair);
4623 		}
4624 		return 0;
4625 	}
4626 
4627 	/* Poll for completing operations. */
4628 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
4629 	if (spdk_unlikely(reaped < 0)) {
4630 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
4631 			    errno, spdk_strerror(errno));
4632 		return -1;
4633 	} else if (reaped == 0) {
4634 		rpoller->stat.idle_polls++;
4635 	}
4636 
4637 	rpoller->stat.polls++;
4638 	rpoller->stat.completions += reaped;
4639 
4640 	for (i = 0; i < reaped; i++) {
4641 
4642 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
4643 
4644 		switch (rdma_wr->type) {
4645 		case RDMA_WR_TYPE_SEND:
4646 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp_wr);
4647 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
4648 
4649 			if (spdk_likely(!wc[i].status)) {
4650 				count++;
4651 				assert(wc[i].opcode == IBV_WC_SEND);
4652 				assert(nvmf_rdma_req_is_completing(rdma_req));
4653 			}
4654 
4655 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
4656 			/* RDMA_WRITE operation completed. +1 since it was chained with rsp WR */
4657 			assert(rqpair->current_send_depth >= (uint32_t)rdma_req->num_outstanding_data_wr + 1);
4658 			rqpair->current_send_depth -= rdma_req->num_outstanding_data_wr + 1;
4659 			rdma_req->num_outstanding_data_wr = 0;
4660 
4661 			nvmf_rdma_request_process(rtransport, rdma_req);
4662 			break;
4663 		case RDMA_WR_TYPE_RECV:
4664 			/* rdma_recv->qpair will be invalid if using an SRQ.  In that case we have to get the qpair from the wc. */
4665 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
4666 			if (rpoller->srq != NULL) {
4667 				rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
4668 				/* It is possible that there are still some completions for destroyed QP
4669 				 * associated with SRQ. We just ignore these late completions and re-post
4670 				 * receive WRs back to SRQ.
4671 				 */
4672 				if (spdk_unlikely(NULL == rdma_recv->qpair)) {
4673 					struct ibv_recv_wr *bad_wr;
4674 
4675 					rdma_recv->wr.next = NULL;
4676 					spdk_rdma_srq_queue_recv_wrs(rpoller->srq, &rdma_recv->wr);
4677 					rc = spdk_rdma_srq_flush_recv_wrs(rpoller->srq, &bad_wr);
4678 					if (rc) {
4679 						SPDK_ERRLOG("Failed to re-post recv WR to SRQ, err %d\n", rc);
4680 					}
4681 					continue;
4682 				}
4683 			}
4684 			rqpair = rdma_recv->qpair;
4685 
4686 			assert(rqpair != NULL);
4687 			if (spdk_likely(!wc[i].status)) {
4688 				assert(wc[i].opcode == IBV_WC_RECV);
4689 				if (rqpair->current_recv_depth >= rqpair->max_queue_depth) {
4690 					spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
4691 					break;
4692 				}
4693 			}
4694 
4695 			rdma_recv->wr.next = NULL;
4696 			rqpair->current_recv_depth++;
4697 			rdma_recv->receive_tsc = poll_tsc;
4698 			rpoller->stat.requests++;
4699 			STAILQ_INSERT_HEAD(&rqpair->resources->incoming_queue, rdma_recv, link);
4700 			break;
4701 		case RDMA_WR_TYPE_DATA:
4702 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data_wr);
4703 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
4704 
4705 			assert(rdma_req->num_outstanding_data_wr > 0);
4706 
4707 			rqpair->current_send_depth--;
4708 			rdma_req->num_outstanding_data_wr--;
4709 			if (spdk_likely(!wc[i].status)) {
4710 				assert(wc[i].opcode == IBV_WC_RDMA_READ);
4711 				rqpair->current_read_depth--;
4712 				/* wait for all outstanding reads associated with the same rdma_req to complete before proceeding. */
4713 				if (rdma_req->num_outstanding_data_wr == 0) {
4714 					if (spdk_unlikely(rdma_req->num_remaining_data_wr)) {
4715 						/* Only part of RDMA_READ operations was submitted, process the rest */
4716 						rc = nvmf_rdma_request_reset_transfer_in(rdma_req, rtransport);
4717 						if (spdk_likely(!rc)) {
4718 							STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
4719 							rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
4720 						} else {
4721 							STAILQ_INSERT_TAIL(&rqpair->pending_rdma_send_queue, rdma_req, state_link);
4722 							rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING;
4723 							rdma_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
4724 						}
4725 						nvmf_rdma_request_process(rtransport, rdma_req);
4726 						break;
4727 					}
4728 					rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
4729 					nvmf_rdma_request_process(rtransport, rdma_req);
4730 				}
4731 			} else {
4732 				/* If the data transfer fails still force the queue into the error state,
4733 				 * if we were performing an RDMA_READ, we need to force the request into a
4734 				 * completed state since it wasn't linked to a send. However, in the RDMA_WRITE
4735 				 * case, we should wait for the SEND to complete. */
4736 				if (rdma_req->data.wr.opcode == IBV_WR_RDMA_READ) {
4737 					rqpair->current_read_depth--;
4738 					if (rdma_req->num_outstanding_data_wr == 0) {
4739 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
4740 					}
4741 				}
4742 			}
4743 			break;
4744 		default:
4745 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
4746 			continue;
4747 		}
4748 
4749 		/* Handle error conditions */
4750 		if (spdk_unlikely(wc[i].status)) {
4751 			rqpair->ibv_in_error_state = true;
4752 			nvmf_rdma_log_wc_status(rqpair, &wc[i]);
4753 
4754 			error = true;
4755 
4756 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
4757 				/* Disconnect the connection. */
4758 				spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
4759 			} else {
4760 				nvmf_rdma_destroy_drained_qpair(rqpair);
4761 			}
4762 			continue;
4763 		}
4764 
4765 		nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
4766 
4767 		if (spdk_unlikely(rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE)) {
4768 			nvmf_rdma_destroy_drained_qpair(rqpair);
4769 		}
4770 	}
4771 
4772 	if (spdk_unlikely(error == true)) {
4773 		return -1;
4774 	}
4775 
4776 	if (reaped == 0) {
4777 		/* In some cases we may not receive any CQE but we still may have pending IO requests waiting for
4778 		 * a resource (e.g. a WR from the data_wr_pool).
4779 		 * We need to start processing of such requests if no CQE reaped */
4780 		nvmf_rdma_poller_process_pending_buf_queue(rtransport, rpoller);
4781 	}
4782 
4783 	/* submit outstanding work requests. */
4784 	_poller_submit_recvs(rtransport, rpoller);
4785 	_poller_submit_sends(rtransport, rpoller);
4786 
4787 	return count;
4788 }
4789 
4790 static void
4791 _nvmf_rdma_remove_destroyed_device(void *c)
4792 {
4793 	struct spdk_nvmf_rdma_transport	*rtransport = c;
4794 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
4795 	int				rc;
4796 
4797 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
4798 		if (device->ready_to_destroy) {
4799 			destroy_ib_device(rtransport, device);
4800 		}
4801 	}
4802 
4803 	free_poll_fds(rtransport);
4804 	rc = generate_poll_fds(rtransport);
4805 	/* cannot handle fd allocation error here */
4806 	if (rc != 0) {
4807 		SPDK_ERRLOG("Failed to generate poll fds after remove ib device.\n");
4808 	}
4809 }
4810 
4811 static void
4812 _nvmf_rdma_remove_poller_in_group_cb(void *c)
4813 {
4814 	struct poller_manage_ctx	*ctx = c;
4815 	struct spdk_nvmf_rdma_transport	*rtransport = ctx->rtransport;
4816 	struct spdk_nvmf_rdma_device	*device = ctx->device;
4817 	struct spdk_thread		*thread = ctx->thread;
4818 
4819 	if (nvmf_rdma_all_pollers_management_done(c)) {
4820 		/* destroy device when last poller is destroyed */
4821 		device->ready_to_destroy = true;
4822 		spdk_thread_send_msg(thread, _nvmf_rdma_remove_destroyed_device, rtransport);
4823 	}
4824 }
4825 
4826 static void
4827 _nvmf_rdma_remove_poller_in_group(void *c)
4828 {
4829 	struct poller_manage_ctx		*ctx = c;
4830 
4831 	ctx->rpoller->need_destroy = true;
4832 	ctx->rpoller->destroy_cb_ctx = ctx;
4833 	ctx->rpoller->destroy_cb = _nvmf_rdma_remove_poller_in_group_cb;
4834 
4835 	/* qp will be disconnected after receiving a RDMA_CM_EVENT_DEVICE_REMOVAL event. */
4836 	if (RB_EMPTY(&ctx->rpoller->qpairs)) {
4837 		nvmf_rdma_poller_destroy(ctx->rpoller);
4838 	}
4839 }
4840 
4841 static int
4842 nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
4843 {
4844 	struct spdk_nvmf_rdma_transport *rtransport;
4845 	struct spdk_nvmf_rdma_poll_group *rgroup;
4846 	struct spdk_nvmf_rdma_poller	*rpoller, *tmp;
4847 	int				count = 0, rc, rc2 = 0;
4848 
4849 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
4850 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
4851 
4852 	TAILQ_FOREACH_SAFE(rpoller, &rgroup->pollers, link, tmp) {
4853 		rc = nvmf_rdma_poller_poll(rtransport, rpoller);
4854 		if (spdk_unlikely(rc < 0)) {
4855 			if (rc2 == 0) {
4856 				rc2 = rc;
4857 			}
4858 			continue;
4859 		}
4860 		count += rc;
4861 	}
4862 
4863 	return rc2 ? rc2 : count;
4864 }
4865 
4866 static int
4867 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
4868 			  struct spdk_nvme_transport_id *trid,
4869 			  bool peer)
4870 {
4871 	struct sockaddr *saddr;
4872 	uint16_t port;
4873 
4874 	spdk_nvme_trid_populate_transport(trid, SPDK_NVME_TRANSPORT_RDMA);
4875 
4876 	if (peer) {
4877 		saddr = rdma_get_peer_addr(id);
4878 	} else {
4879 		saddr = rdma_get_local_addr(id);
4880 	}
4881 	switch (saddr->sa_family) {
4882 	case AF_INET: {
4883 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
4884 
4885 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
4886 		inet_ntop(AF_INET, &saddr_in->sin_addr,
4887 			  trid->traddr, sizeof(trid->traddr));
4888 		if (peer) {
4889 			port = ntohs(rdma_get_dst_port(id));
4890 		} else {
4891 			port = ntohs(rdma_get_src_port(id));
4892 		}
4893 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
4894 		break;
4895 	}
4896 	case AF_INET6: {
4897 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
4898 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
4899 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
4900 			  trid->traddr, sizeof(trid->traddr));
4901 		if (peer) {
4902 			port = ntohs(rdma_get_dst_port(id));
4903 		} else {
4904 			port = ntohs(rdma_get_src_port(id));
4905 		}
4906 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
4907 		break;
4908 	}
4909 	default:
4910 		return -1;
4911 
4912 	}
4913 
4914 	return 0;
4915 }
4916 
4917 static int
4918 nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
4919 			      struct spdk_nvme_transport_id *trid)
4920 {
4921 	struct spdk_nvmf_rdma_qpair	*rqpair;
4922 
4923 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4924 
4925 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
4926 }
4927 
4928 static int
4929 nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
4930 			       struct spdk_nvme_transport_id *trid)
4931 {
4932 	struct spdk_nvmf_rdma_qpair	*rqpair;
4933 
4934 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4935 
4936 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
4937 }
4938 
4939 static int
4940 nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
4941 				struct spdk_nvme_transport_id *trid)
4942 {
4943 	struct spdk_nvmf_rdma_qpair	*rqpair;
4944 
4945 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4946 
4947 	return nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
4948 }
4949 
4950 void
4951 spdk_nvmf_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
4952 {
4953 	g_nvmf_hooks = *hooks;
4954 }
4955 
4956 static void
4957 nvmf_rdma_request_set_abort_status(struct spdk_nvmf_request *req,
4958 				   struct spdk_nvmf_rdma_request *rdma_req_to_abort,
4959 				   struct spdk_nvmf_rdma_qpair *rqpair)
4960 {
4961 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
4962 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_BY_REQUEST;
4963 
4964 	STAILQ_INSERT_TAIL(&rqpair->pending_rdma_send_queue, rdma_req_to_abort, state_link);
4965 	rdma_req_to_abort->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING;
4966 
4967 	req->rsp->nvme_cpl.cdw0 &= ~1U;	/* Command was successfully aborted. */
4968 }
4969 
4970 static int
4971 _nvmf_rdma_qpair_abort_request(void *ctx)
4972 {
4973 	struct spdk_nvmf_request *req = ctx;
4974 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = SPDK_CONTAINEROF(
4975 				req->req_to_abort, struct spdk_nvmf_rdma_request, req);
4976 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(req->req_to_abort->qpair,
4977 					      struct spdk_nvmf_rdma_qpair, qpair);
4978 	int rc;
4979 
4980 	spdk_poller_unregister(&req->poller);
4981 
4982 	switch (rdma_req_to_abort->state) {
4983 	case RDMA_REQUEST_STATE_EXECUTING:
4984 		rc = nvmf_ctrlr_abort_request(req);
4985 		if (rc == SPDK_NVMF_REQUEST_EXEC_STATUS_ASYNCHRONOUS) {
4986 			return SPDK_POLLER_BUSY;
4987 		}
4988 		break;
4989 
4990 	case RDMA_REQUEST_STATE_NEED_BUFFER:
4991 		STAILQ_REMOVE(&rqpair->poller->group->group.pending_buf_queue,
4992 			      &rdma_req_to_abort->req, spdk_nvmf_request, buf_link);
4993 
4994 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort, rqpair);
4995 		break;
4996 
4997 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
4998 		STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req_to_abort,
4999 			      spdk_nvmf_rdma_request, state_link);
5000 
5001 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort, rqpair);
5002 		break;
5003 
5004 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
5005 		STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req_to_abort,
5006 			      spdk_nvmf_rdma_request, state_link);
5007 
5008 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort, rqpair);
5009 		break;
5010 
5011 	case RDMA_REQUEST_STATE_READY_TO_COMPLETE_PENDING:
5012 		/* Remove req from the list here to re-use common function */
5013 		STAILQ_REMOVE(&rqpair->pending_rdma_send_queue, rdma_req_to_abort,
5014 			      spdk_nvmf_rdma_request, state_link);
5015 
5016 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort, rqpair);
5017 		break;
5018 
5019 	case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
5020 		if (spdk_get_ticks() < req->timeout_tsc) {
5021 			req->poller = SPDK_POLLER_REGISTER(_nvmf_rdma_qpair_abort_request, req, 0);
5022 			return SPDK_POLLER_BUSY;
5023 		}
5024 		break;
5025 
5026 	default:
5027 		break;
5028 	}
5029 
5030 	spdk_nvmf_request_complete(req);
5031 	return SPDK_POLLER_BUSY;
5032 }
5033 
5034 static void
5035 nvmf_rdma_qpair_abort_request(struct spdk_nvmf_qpair *qpair,
5036 			      struct spdk_nvmf_request *req)
5037 {
5038 	struct spdk_nvmf_rdma_qpair *rqpair;
5039 	struct spdk_nvmf_rdma_transport *rtransport;
5040 	struct spdk_nvmf_transport *transport;
5041 	uint16_t cid;
5042 	uint32_t i, max_req_count;
5043 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = NULL, *rdma_req;
5044 
5045 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
5046 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
5047 	transport = &rtransport->transport;
5048 
5049 	cid = req->cmd->nvme_cmd.cdw10_bits.abort.cid;
5050 	max_req_count = rqpair->srq == NULL ? rqpair->max_queue_depth : rqpair->poller->max_srq_depth;
5051 
5052 	for (i = 0; i < max_req_count; i++) {
5053 		rdma_req = &rqpair->resources->reqs[i];
5054 		/* When SRQ == NULL, rqpair has its own requests and req.qpair pointer always points to the qpair
5055 		 * When SRQ != NULL all rqpairs share common requests and qpair pointer is assigned when we start to
5056 		 * process a request. So in both cases all requests which are not in FREE state have valid qpair ptr */
5057 		if (rdma_req->state != RDMA_REQUEST_STATE_FREE && rdma_req->req.cmd->nvme_cmd.cid == cid &&
5058 		    rdma_req->req.qpair == qpair) {
5059 			rdma_req_to_abort = rdma_req;
5060 			break;
5061 		}
5062 	}
5063 
5064 	if (rdma_req_to_abort == NULL) {
5065 		spdk_nvmf_request_complete(req);
5066 		return;
5067 	}
5068 
5069 	req->req_to_abort = &rdma_req_to_abort->req;
5070 	req->timeout_tsc = spdk_get_ticks() +
5071 			   transport->opts.abort_timeout_sec * spdk_get_ticks_hz();
5072 	req->poller = NULL;
5073 
5074 	_nvmf_rdma_qpair_abort_request(req);
5075 }
5076 
5077 static void
5078 nvmf_rdma_poll_group_dump_stat(struct spdk_nvmf_transport_poll_group *group,
5079 			       struct spdk_json_write_ctx *w)
5080 {
5081 	struct spdk_nvmf_rdma_poll_group *rgroup;
5082 	struct spdk_nvmf_rdma_poller *rpoller;
5083 
5084 	assert(w != NULL);
5085 
5086 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
5087 
5088 	spdk_json_write_named_uint64(w, "pending_data_buffer", rgroup->stat.pending_data_buffer);
5089 
5090 	spdk_json_write_named_array_begin(w, "devices");
5091 
5092 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
5093 		spdk_json_write_object_begin(w);
5094 		spdk_json_write_named_string(w, "name",
5095 					     ibv_get_device_name(rpoller->device->context->device));
5096 		spdk_json_write_named_uint64(w, "polls",
5097 					     rpoller->stat.polls);
5098 		spdk_json_write_named_uint64(w, "idle_polls",
5099 					     rpoller->stat.idle_polls);
5100 		spdk_json_write_named_uint64(w, "completions",
5101 					     rpoller->stat.completions);
5102 		spdk_json_write_named_uint64(w, "requests",
5103 					     rpoller->stat.requests);
5104 		spdk_json_write_named_uint64(w, "request_latency",
5105 					     rpoller->stat.request_latency);
5106 		spdk_json_write_named_uint64(w, "pending_free_request",
5107 					     rpoller->stat.pending_free_request);
5108 		spdk_json_write_named_uint64(w, "pending_rdma_read",
5109 					     rpoller->stat.pending_rdma_read);
5110 		spdk_json_write_named_uint64(w, "pending_rdma_write",
5111 					     rpoller->stat.pending_rdma_write);
5112 		spdk_json_write_named_uint64(w, "pending_rdma_send",
5113 					     rpoller->stat.pending_rdma_send);
5114 		spdk_json_write_named_uint64(w, "total_send_wrs",
5115 					     rpoller->stat.qp_stats.send.num_submitted_wrs);
5116 		spdk_json_write_named_uint64(w, "send_doorbell_updates",
5117 					     rpoller->stat.qp_stats.send.doorbell_updates);
5118 		spdk_json_write_named_uint64(w, "total_recv_wrs",
5119 					     rpoller->stat.qp_stats.recv.num_submitted_wrs);
5120 		spdk_json_write_named_uint64(w, "recv_doorbell_updates",
5121 					     rpoller->stat.qp_stats.recv.doorbell_updates);
5122 		spdk_json_write_object_end(w);
5123 	}
5124 
5125 	spdk_json_write_array_end(w);
5126 }
5127 
5128 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
5129 	.name = "RDMA",
5130 	.type = SPDK_NVME_TRANSPORT_RDMA,
5131 	.opts_init = nvmf_rdma_opts_init,
5132 	.create = nvmf_rdma_create,
5133 	.dump_opts = nvmf_rdma_dump_opts,
5134 	.destroy = nvmf_rdma_destroy,
5135 
5136 	.listen = nvmf_rdma_listen,
5137 	.stop_listen = nvmf_rdma_stop_listen,
5138 	.cdata_init = nvmf_rdma_cdata_init,
5139 
5140 	.listener_discover = nvmf_rdma_discover,
5141 
5142 	.poll_group_create = nvmf_rdma_poll_group_create,
5143 	.get_optimal_poll_group = nvmf_rdma_get_optimal_poll_group,
5144 	.poll_group_destroy = nvmf_rdma_poll_group_destroy,
5145 	.poll_group_add = nvmf_rdma_poll_group_add,
5146 	.poll_group_remove = nvmf_rdma_poll_group_remove,
5147 	.poll_group_poll = nvmf_rdma_poll_group_poll,
5148 
5149 	.req_free = nvmf_rdma_request_free,
5150 	.req_complete = nvmf_rdma_request_complete,
5151 
5152 	.qpair_fini = nvmf_rdma_close_qpair,
5153 	.qpair_get_peer_trid = nvmf_rdma_qpair_get_peer_trid,
5154 	.qpair_get_local_trid = nvmf_rdma_qpair_get_local_trid,
5155 	.qpair_get_listen_trid = nvmf_rdma_qpair_get_listen_trid,
5156 	.qpair_abort_request = nvmf_rdma_qpair_abort_request,
5157 
5158 	.poll_group_dump_stat = nvmf_rdma_poll_group_dump_stat,
5159 };
5160 
5161 SPDK_NVMF_TRANSPORT_REGISTER(rdma, &spdk_nvmf_transport_rdma);
5162 SPDK_LOG_REGISTER_COMPONENT(rdma)
5163