xref: /spdk/lib/nvmf/rdma.c (revision da60639f86dd88295eb46c2d76f9c327db92d7b3)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2019, 2020 Mellanox Technologies LTD. All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "spdk/stdinc.h"
35 
36 #include "spdk/config.h"
37 #include "spdk/thread.h"
38 #include "spdk/likely.h"
39 #include "spdk/nvmf_transport.h"
40 #include "spdk/string.h"
41 #include "spdk/trace.h"
42 #include "spdk/util.h"
43 
44 #include "spdk_internal/assert.h"
45 #include "spdk_internal/log.h"
46 #include "spdk_internal/rdma.h"
47 
48 #include "nvmf_internal.h"
49 
50 struct spdk_nvme_rdma_hooks g_nvmf_hooks = {};
51 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma;
52 
53 /*
54  RDMA Connection Resource Defaults
55  */
56 #define NVMF_DEFAULT_TX_SGE		SPDK_NVMF_MAX_SGL_ENTRIES
57 #define NVMF_DEFAULT_RSP_SGE		1
58 #define NVMF_DEFAULT_RX_SGE		2
59 
60 /* The RDMA completion queue size */
61 #define DEFAULT_NVMF_RDMA_CQ_SIZE	4096
62 #define MAX_WR_PER_QP(queue_depth)	(queue_depth * 3 + 2)
63 
64 /* Timeout for destroying defunct rqpairs */
65 #define NVMF_RDMA_QPAIR_DESTROY_TIMEOUT_US	4000000
66 
67 static int g_spdk_nvmf_ibv_query_mask =
68 	IBV_QP_STATE |
69 	IBV_QP_PKEY_INDEX |
70 	IBV_QP_PORT |
71 	IBV_QP_ACCESS_FLAGS |
72 	IBV_QP_AV |
73 	IBV_QP_PATH_MTU |
74 	IBV_QP_DEST_QPN |
75 	IBV_QP_RQ_PSN |
76 	IBV_QP_MAX_DEST_RD_ATOMIC |
77 	IBV_QP_MIN_RNR_TIMER |
78 	IBV_QP_SQ_PSN |
79 	IBV_QP_TIMEOUT |
80 	IBV_QP_RETRY_CNT |
81 	IBV_QP_RNR_RETRY |
82 	IBV_QP_MAX_QP_RD_ATOMIC;
83 
84 enum spdk_nvmf_rdma_request_state {
85 	/* The request is not currently in use */
86 	RDMA_REQUEST_STATE_FREE = 0,
87 
88 	/* Initial state when request first received */
89 	RDMA_REQUEST_STATE_NEW,
90 
91 	/* The request is queued until a data buffer is available. */
92 	RDMA_REQUEST_STATE_NEED_BUFFER,
93 
94 	/* The request is waiting on RDMA queue depth availability
95 	 * to transfer data from the host to the controller.
96 	 */
97 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
98 
99 	/* The request is currently transferring data from the host to the controller. */
100 	RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
101 
102 	/* The request is ready to execute at the block device */
103 	RDMA_REQUEST_STATE_READY_TO_EXECUTE,
104 
105 	/* The request is currently executing at the block device */
106 	RDMA_REQUEST_STATE_EXECUTING,
107 
108 	/* The request finished executing at the block device */
109 	RDMA_REQUEST_STATE_EXECUTED,
110 
111 	/* The request is waiting on RDMA queue depth availability
112 	 * to transfer data from the controller to the host.
113 	 */
114 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
115 
116 	/* The request is ready to send a completion */
117 	RDMA_REQUEST_STATE_READY_TO_COMPLETE,
118 
119 	/* The request is currently transferring data from the controller to the host. */
120 	RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
121 
122 	/* The request currently has an outstanding completion without an
123 	 * associated data transfer.
124 	 */
125 	RDMA_REQUEST_STATE_COMPLETING,
126 
127 	/* The request completed and can be marked free. */
128 	RDMA_REQUEST_STATE_COMPLETED,
129 
130 	/* Terminator */
131 	RDMA_REQUEST_NUM_STATES,
132 };
133 
134 #define OBJECT_NVMF_RDMA_IO				0x40
135 
136 #define TRACE_GROUP_NVMF_RDMA				0x4
137 #define TRACE_RDMA_REQUEST_STATE_NEW					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x0)
138 #define TRACE_RDMA_REQUEST_STATE_NEED_BUFFER				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x1)
139 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x2)
140 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x3)
141 #define TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x4)
142 #define TRACE_RDMA_REQUEST_STATE_EXECUTING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x5)
143 #define TRACE_RDMA_REQUEST_STATE_EXECUTED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x6)
144 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING		SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x7)
145 #define TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x8)
146 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x9)
147 #define TRACE_RDMA_REQUEST_STATE_COMPLETING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xA)
148 #define TRACE_RDMA_REQUEST_STATE_COMPLETED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xB)
149 #define TRACE_RDMA_QP_CREATE						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xC)
150 #define TRACE_RDMA_IBV_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xD)
151 #define TRACE_RDMA_CM_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xE)
152 #define TRACE_RDMA_QP_STATE_CHANGE					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xF)
153 #define TRACE_RDMA_QP_DISCONNECT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x10)
154 #define TRACE_RDMA_QP_DESTROY						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x11)
155 
156 SPDK_TRACE_REGISTER_FN(nvmf_trace, "nvmf_rdma", TRACE_GROUP_NVMF_RDMA)
157 {
158 	spdk_trace_register_object(OBJECT_NVMF_RDMA_IO, 'r');
159 	spdk_trace_register_description("RDMA_REQ_NEW", TRACE_RDMA_REQUEST_STATE_NEW,
160 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 1, 1, "cmid:   ");
161 	spdk_trace_register_description("RDMA_REQ_NEED_BUFFER", TRACE_RDMA_REQUEST_STATE_NEED_BUFFER,
162 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
163 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_C2H",
164 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
165 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
166 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_H2C",
167 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
168 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
169 	spdk_trace_register_description("RDMA_REQ_TX_H2C",
170 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
171 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
172 	spdk_trace_register_description("RDMA_REQ_RDY_TO_EXECUTE",
173 					TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE,
174 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
175 	spdk_trace_register_description("RDMA_REQ_EXECUTING",
176 					TRACE_RDMA_REQUEST_STATE_EXECUTING,
177 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
178 	spdk_trace_register_description("RDMA_REQ_EXECUTED",
179 					TRACE_RDMA_REQUEST_STATE_EXECUTED,
180 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
181 	spdk_trace_register_description("RDMA_REQ_RDY_TO_COMPL",
182 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE,
183 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
184 	spdk_trace_register_description("RDMA_REQ_COMPLETING_C2H",
185 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
186 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
187 	spdk_trace_register_description("RDMA_REQ_COMPLETING",
188 					TRACE_RDMA_REQUEST_STATE_COMPLETING,
189 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
190 	spdk_trace_register_description("RDMA_REQ_COMPLETED",
191 					TRACE_RDMA_REQUEST_STATE_COMPLETED,
192 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
193 
194 	spdk_trace_register_description("RDMA_QP_CREATE", TRACE_RDMA_QP_CREATE,
195 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
196 	spdk_trace_register_description("RDMA_IBV_ASYNC_EVENT", TRACE_RDMA_IBV_ASYNC_EVENT,
197 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
198 	spdk_trace_register_description("RDMA_CM_ASYNC_EVENT", TRACE_RDMA_CM_ASYNC_EVENT,
199 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
200 	spdk_trace_register_description("RDMA_QP_STATE_CHANGE", TRACE_RDMA_QP_STATE_CHANGE,
201 					OWNER_NONE, OBJECT_NONE, 0, 1, "state:  ");
202 	spdk_trace_register_description("RDMA_QP_DISCONNECT", TRACE_RDMA_QP_DISCONNECT,
203 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
204 	spdk_trace_register_description("RDMA_QP_DESTROY", TRACE_RDMA_QP_DESTROY,
205 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
206 }
207 
208 enum spdk_nvmf_rdma_wr_type {
209 	RDMA_WR_TYPE_RECV,
210 	RDMA_WR_TYPE_SEND,
211 	RDMA_WR_TYPE_DATA,
212 };
213 
214 struct spdk_nvmf_rdma_wr {
215 	enum spdk_nvmf_rdma_wr_type	type;
216 };
217 
218 /* This structure holds commands as they are received off the wire.
219  * It must be dynamically paired with a full request object
220  * (spdk_nvmf_rdma_request) to service a request. It is separate
221  * from the request because RDMA does not appear to order
222  * completions, so occasionally we'll get a new incoming
223  * command when there aren't any free request objects.
224  */
225 struct spdk_nvmf_rdma_recv {
226 	struct ibv_recv_wr			wr;
227 	struct ibv_sge				sgl[NVMF_DEFAULT_RX_SGE];
228 
229 	struct spdk_nvmf_rdma_qpair		*qpair;
230 
231 	/* In-capsule data buffer */
232 	uint8_t					*buf;
233 
234 	struct spdk_nvmf_rdma_wr		rdma_wr;
235 	uint64_t				receive_tsc;
236 
237 	STAILQ_ENTRY(spdk_nvmf_rdma_recv)	link;
238 };
239 
240 struct spdk_nvmf_rdma_request_data {
241 	struct spdk_nvmf_rdma_wr	rdma_wr;
242 	struct ibv_send_wr		wr;
243 	struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
244 };
245 
246 struct spdk_nvmf_rdma_request {
247 	struct spdk_nvmf_request		req;
248 
249 	enum spdk_nvmf_rdma_request_state	state;
250 
251 	struct spdk_nvmf_rdma_recv		*recv;
252 
253 	struct {
254 		struct spdk_nvmf_rdma_wr	rdma_wr;
255 		struct	ibv_send_wr		wr;
256 		struct	ibv_sge			sgl[NVMF_DEFAULT_RSP_SGE];
257 	} rsp;
258 
259 	struct spdk_nvmf_rdma_request_data	data;
260 
261 	uint32_t				iovpos;
262 
263 	uint32_t				num_outstanding_data_wr;
264 	uint64_t				receive_tsc;
265 
266 	STAILQ_ENTRY(spdk_nvmf_rdma_request)	state_link;
267 };
268 
269 enum spdk_nvmf_rdma_qpair_disconnect_flags {
270 	RDMA_QP_DISCONNECTING		= 1,
271 	RDMA_QP_RECV_DRAINED		= 1 << 1,
272 	RDMA_QP_SEND_DRAINED		= 1 << 2
273 };
274 
275 struct spdk_nvmf_rdma_resource_opts {
276 	struct spdk_nvmf_rdma_qpair	*qpair;
277 	/* qp points either to an ibv_qp object or an ibv_srq object depending on the value of shared. */
278 	void				*qp;
279 	struct ibv_pd			*pd;
280 	uint32_t			max_queue_depth;
281 	uint32_t			in_capsule_data_size;
282 	bool				shared;
283 };
284 
285 struct spdk_nvmf_send_wr_list {
286 	struct ibv_send_wr	*first;
287 	struct ibv_send_wr	*last;
288 };
289 
290 struct spdk_nvmf_recv_wr_list {
291 	struct ibv_recv_wr	*first;
292 	struct ibv_recv_wr	*last;
293 };
294 
295 struct spdk_nvmf_rdma_resources {
296 	/* Array of size "max_queue_depth" containing RDMA requests. */
297 	struct spdk_nvmf_rdma_request		*reqs;
298 
299 	/* Array of size "max_queue_depth" containing RDMA recvs. */
300 	struct spdk_nvmf_rdma_recv		*recvs;
301 
302 	/* Array of size "max_queue_depth" containing 64 byte capsules
303 	 * used for receive.
304 	 */
305 	union nvmf_h2c_msg			*cmds;
306 	struct ibv_mr				*cmds_mr;
307 
308 	/* Array of size "max_queue_depth" containing 16 byte completions
309 	 * to be sent back to the user.
310 	 */
311 	union nvmf_c2h_msg			*cpls;
312 	struct ibv_mr				*cpls_mr;
313 
314 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
315 	 * buffers to be used for in capsule data.
316 	 */
317 	void					*bufs;
318 	struct ibv_mr				*bufs_mr;
319 
320 	/* The list of pending recvs to transfer */
321 	struct spdk_nvmf_recv_wr_list		recvs_to_post;
322 
323 	/* Receives that are waiting for a request object */
324 	STAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
325 
326 	/* Queue to track free requests */
327 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	free_queue;
328 };
329 
330 typedef void (*spdk_nvmf_rdma_qpair_ibv_event)(struct spdk_nvmf_rdma_qpair *rqpair);
331 
332 struct spdk_nvmf_rdma_ibv_event_ctx {
333 	struct spdk_nvmf_rdma_qpair			*rqpair;
334 	spdk_nvmf_rdma_qpair_ibv_event			cb_fn;
335 	/* Link to other ibv events associated with this qpair */
336 	STAILQ_ENTRY(spdk_nvmf_rdma_ibv_event_ctx)	link;
337 };
338 
339 struct spdk_nvmf_rdma_qpair {
340 	struct spdk_nvmf_qpair			qpair;
341 
342 	struct spdk_nvmf_rdma_device		*device;
343 	struct spdk_nvmf_rdma_poller		*poller;
344 
345 	struct spdk_rdma_qp			*rdma_qp;
346 	struct rdma_cm_id			*cm_id;
347 	struct ibv_srq				*srq;
348 	struct rdma_cm_id			*listen_id;
349 
350 	/* The maximum number of I/O outstanding on this connection at one time */
351 	uint16_t				max_queue_depth;
352 
353 	/* The maximum number of active RDMA READ and ATOMIC operations at one time */
354 	uint16_t				max_read_depth;
355 
356 	/* The maximum number of RDMA SEND operations at one time */
357 	uint32_t				max_send_depth;
358 
359 	/* The current number of outstanding WRs from this qpair's
360 	 * recv queue. Should not exceed device->attr.max_queue_depth.
361 	 */
362 	uint16_t				current_recv_depth;
363 
364 	/* The current number of active RDMA READ operations */
365 	uint16_t				current_read_depth;
366 
367 	/* The current number of posted WRs from this qpair's
368 	 * send queue. Should not exceed max_send_depth.
369 	 */
370 	uint32_t				current_send_depth;
371 
372 	/* The maximum number of SGEs per WR on the send queue */
373 	uint32_t				max_send_sge;
374 
375 	/* The maximum number of SGEs per WR on the recv queue */
376 	uint32_t				max_recv_sge;
377 
378 	struct spdk_nvmf_rdma_resources		*resources;
379 
380 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_read_queue;
381 
382 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_write_queue;
383 
384 	/* Number of requests not in the free state */
385 	uint32_t				qd;
386 
387 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	link;
388 
389 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	recv_link;
390 
391 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	send_link;
392 
393 	/* IBV queue pair attributes: they are used to manage
394 	 * qp state and recover from errors.
395 	 */
396 	enum ibv_qp_state			ibv_state;
397 
398 	uint32_t				disconnect_flags;
399 
400 	/* Poller registered in case the qpair doesn't properly
401 	 * complete the qpair destruct process and becomes defunct.
402 	 */
403 
404 	struct spdk_poller			*destruct_poller;
405 
406 	/*
407 	 * io_channel which is used to destroy qpair when it is removed from poll group
408 	 */
409 	struct spdk_io_channel		*destruct_channel;
410 
411 	/* List of ibv async events */
412 	STAILQ_HEAD(, spdk_nvmf_rdma_ibv_event_ctx)	ibv_events;
413 
414 	/* There are several ways a disconnect can start on a qpair
415 	 * and they are not all mutually exclusive. It is important
416 	 * that we only initialize one of these paths.
417 	 */
418 	bool					disconnect_started;
419 	/* Lets us know that we have received the last_wqe event. */
420 	bool					last_wqe_reached;
421 };
422 
423 struct spdk_nvmf_rdma_poller_stat {
424 	uint64_t				completions;
425 	uint64_t				polls;
426 	uint64_t				requests;
427 	uint64_t				request_latency;
428 	uint64_t				pending_free_request;
429 	uint64_t				pending_rdma_read;
430 	uint64_t				pending_rdma_write;
431 };
432 
433 struct spdk_nvmf_rdma_poller {
434 	struct spdk_nvmf_rdma_device		*device;
435 	struct spdk_nvmf_rdma_poll_group	*group;
436 
437 	int					num_cqe;
438 	int					required_num_wr;
439 	struct ibv_cq				*cq;
440 
441 	/* The maximum number of I/O outstanding on the shared receive queue at one time */
442 	uint16_t				max_srq_depth;
443 
444 	/* Shared receive queue */
445 	struct ibv_srq				*srq;
446 
447 	struct spdk_nvmf_rdma_resources		*resources;
448 	struct spdk_nvmf_rdma_poller_stat	stat;
449 
450 	TAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs;
451 
452 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_recv;
453 
454 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_send;
455 
456 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
457 };
458 
459 struct spdk_nvmf_rdma_poll_group_stat {
460 	uint64_t				pending_data_buffer;
461 };
462 
463 struct spdk_nvmf_rdma_poll_group {
464 	struct spdk_nvmf_transport_poll_group		group;
465 	struct spdk_nvmf_rdma_poll_group_stat		stat;
466 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)		pollers;
467 	TAILQ_ENTRY(spdk_nvmf_rdma_poll_group)		link;
468 	/*
469 	 * buffers which are split across multiple RDMA
470 	 * memory regions cannot be used by this transport.
471 	 */
472 	STAILQ_HEAD(, spdk_nvmf_transport_pg_cache_buf)	retired_bufs;
473 };
474 
475 struct spdk_nvmf_rdma_conn_sched {
476 	struct spdk_nvmf_rdma_poll_group *next_admin_pg;
477 	struct spdk_nvmf_rdma_poll_group *next_io_pg;
478 };
479 
480 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
481 struct spdk_nvmf_rdma_device {
482 	struct ibv_device_attr			attr;
483 	struct ibv_context			*context;
484 
485 	struct spdk_mem_map			*map;
486 	struct ibv_pd				*pd;
487 
488 	int					num_srq;
489 
490 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
491 };
492 
493 struct spdk_nvmf_rdma_port {
494 	const struct spdk_nvme_transport_id	*trid;
495 	struct rdma_cm_id			*id;
496 	struct spdk_nvmf_rdma_device		*device;
497 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
498 };
499 
500 struct spdk_nvmf_rdma_transport {
501 	struct spdk_nvmf_transport	transport;
502 
503 	struct spdk_nvmf_rdma_conn_sched conn_sched;
504 
505 	struct rdma_event_channel	*event_channel;
506 
507 	struct spdk_mempool		*data_wr_pool;
508 
509 	pthread_mutex_t			lock;
510 
511 	/* fields used to poll RDMA/IB events */
512 	nfds_t			npoll_fds;
513 	struct pollfd		*poll_fds;
514 
515 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
516 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
517 	TAILQ_HEAD(, spdk_nvmf_rdma_poll_group)	poll_groups;
518 };
519 
520 static inline void
521 nvmf_rdma_start_disconnect(struct spdk_nvmf_rdma_qpair *rqpair);
522 
523 static bool
524 nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
525 			  struct spdk_nvmf_rdma_request *rdma_req);
526 
527 static inline int
528 nvmf_rdma_check_ibv_state(enum ibv_qp_state state)
529 {
530 	switch (state) {
531 	case IBV_QPS_RESET:
532 	case IBV_QPS_INIT:
533 	case IBV_QPS_RTR:
534 	case IBV_QPS_RTS:
535 	case IBV_QPS_SQD:
536 	case IBV_QPS_SQE:
537 	case IBV_QPS_ERR:
538 		return 0;
539 	default:
540 		return -1;
541 	}
542 }
543 
544 static inline enum spdk_nvme_media_error_status_code
545 nvmf_rdma_dif_error_to_compl_status(uint8_t err_type) {
546 	enum spdk_nvme_media_error_status_code result;
547 	switch (err_type)
548 	{
549 	case SPDK_DIF_REFTAG_ERROR:
550 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
551 		break;
552 	case SPDK_DIF_APPTAG_ERROR:
553 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
554 		break;
555 	case SPDK_DIF_GUARD_ERROR:
556 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
557 		break;
558 	default:
559 		SPDK_UNREACHABLE();
560 	}
561 
562 	return result;
563 }
564 
565 static enum ibv_qp_state
566 nvmf_rdma_update_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair) {
567 	enum ibv_qp_state old_state, new_state;
568 	struct ibv_qp_attr qp_attr;
569 	struct ibv_qp_init_attr init_attr;
570 	int rc;
571 
572 	old_state = rqpair->ibv_state;
573 	rc = ibv_query_qp(rqpair->rdma_qp->qp, &qp_attr,
574 			  g_spdk_nvmf_ibv_query_mask, &init_attr);
575 
576 	if (rc)
577 	{
578 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
579 		return IBV_QPS_ERR + 1;
580 	}
581 
582 	new_state = qp_attr.qp_state;
583 	rqpair->ibv_state = new_state;
584 	qp_attr.ah_attr.port_num = qp_attr.port_num;
585 
586 	rc = nvmf_rdma_check_ibv_state(new_state);
587 	if (rc)
588 	{
589 		SPDK_ERRLOG("QP#%d: bad state updated: %u, maybe hardware issue\n", rqpair->qpair.qid, new_state);
590 		/*
591 		 * IBV_QPS_UNKNOWN undefined if lib version smaller than libibverbs-1.1.8
592 		 * IBV_QPS_UNKNOWN is the enum element after IBV_QPS_ERR
593 		 */
594 		return IBV_QPS_ERR + 1;
595 	}
596 
597 	if (old_state != new_state)
598 	{
599 		spdk_trace_record(TRACE_RDMA_QP_STATE_CHANGE, 0, 0,
600 				  (uintptr_t)rqpair->cm_id, new_state);
601 	}
602 	return new_state;
603 }
604 
605 static void
606 nvmf_rdma_request_free_data(struct spdk_nvmf_rdma_request *rdma_req,
607 			    struct spdk_nvmf_rdma_transport *rtransport)
608 {
609 	struct spdk_nvmf_rdma_request_data	*data_wr;
610 	struct ibv_send_wr			*next_send_wr;
611 	uint64_t				req_wrid;
612 
613 	rdma_req->num_outstanding_data_wr = 0;
614 	data_wr = &rdma_req->data;
615 	req_wrid = data_wr->wr.wr_id;
616 	while (data_wr && data_wr->wr.wr_id == req_wrid) {
617 		memset(data_wr->sgl, 0, sizeof(data_wr->wr.sg_list[0]) * data_wr->wr.num_sge);
618 		data_wr->wr.num_sge = 0;
619 		next_send_wr = data_wr->wr.next;
620 		if (data_wr != &rdma_req->data) {
621 			spdk_mempool_put(rtransport->data_wr_pool, data_wr);
622 		}
623 		data_wr = (!next_send_wr || next_send_wr == &rdma_req->rsp.wr) ? NULL :
624 			  SPDK_CONTAINEROF(next_send_wr, struct spdk_nvmf_rdma_request_data, wr);
625 	}
626 }
627 
628 static void
629 nvmf_rdma_dump_request(struct spdk_nvmf_rdma_request *req)
630 {
631 	SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", req->req.data_from_pool);
632 	if (req->req.cmd) {
633 		SPDK_ERRLOG("\t\tRequest opcode: %d\n", req->req.cmd->nvmf_cmd.opcode);
634 	}
635 	if (req->recv) {
636 		SPDK_ERRLOG("\t\tRequest recv wr_id%lu\n", req->recv->wr.wr_id);
637 	}
638 }
639 
640 static void
641 nvmf_rdma_dump_qpair_contents(struct spdk_nvmf_rdma_qpair *rqpair)
642 {
643 	int i;
644 
645 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", rqpair->qpair.qid);
646 	for (i = 0; i < rqpair->max_queue_depth; i++) {
647 		if (rqpair->resources->reqs[i].state != RDMA_REQUEST_STATE_FREE) {
648 			nvmf_rdma_dump_request(&rqpair->resources->reqs[i]);
649 		}
650 	}
651 }
652 
653 static void
654 nvmf_rdma_resources_destroy(struct spdk_nvmf_rdma_resources *resources)
655 {
656 	if (resources->cmds_mr) {
657 		ibv_dereg_mr(resources->cmds_mr);
658 	}
659 
660 	if (resources->cpls_mr) {
661 		ibv_dereg_mr(resources->cpls_mr);
662 	}
663 
664 	if (resources->bufs_mr) {
665 		ibv_dereg_mr(resources->bufs_mr);
666 	}
667 
668 	spdk_free(resources->cmds);
669 	spdk_free(resources->cpls);
670 	spdk_free(resources->bufs);
671 	free(resources->reqs);
672 	free(resources->recvs);
673 	free(resources);
674 }
675 
676 
677 static struct spdk_nvmf_rdma_resources *
678 nvmf_rdma_resources_create(struct spdk_nvmf_rdma_resource_opts *opts)
679 {
680 	struct spdk_nvmf_rdma_resources	*resources;
681 	struct spdk_nvmf_rdma_request	*rdma_req;
682 	struct spdk_nvmf_rdma_recv	*rdma_recv;
683 	struct ibv_qp			*qp;
684 	struct ibv_srq			*srq;
685 	uint32_t			i;
686 	int				rc;
687 
688 	resources = calloc(1, sizeof(struct spdk_nvmf_rdma_resources));
689 	if (!resources) {
690 		SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
691 		return NULL;
692 	}
693 
694 	resources->reqs = calloc(opts->max_queue_depth, sizeof(*resources->reqs));
695 	resources->recvs = calloc(opts->max_queue_depth, sizeof(*resources->recvs));
696 	resources->cmds = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cmds),
697 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
698 	resources->cpls = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cpls),
699 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
700 
701 	if (opts->in_capsule_data_size > 0) {
702 		resources->bufs = spdk_zmalloc(opts->max_queue_depth * opts->in_capsule_data_size,
703 					       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY,
704 					       SPDK_MALLOC_DMA);
705 	}
706 
707 	if (!resources->reqs || !resources->recvs || !resources->cmds ||
708 	    !resources->cpls || (opts->in_capsule_data_size && !resources->bufs)) {
709 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
710 		goto cleanup;
711 	}
712 
713 	resources->cmds_mr = ibv_reg_mr(opts->pd, resources->cmds,
714 					opts->max_queue_depth * sizeof(*resources->cmds),
715 					IBV_ACCESS_LOCAL_WRITE);
716 	resources->cpls_mr = ibv_reg_mr(opts->pd, resources->cpls,
717 					opts->max_queue_depth * sizeof(*resources->cpls),
718 					0);
719 
720 	if (opts->in_capsule_data_size) {
721 		resources->bufs_mr = ibv_reg_mr(opts->pd, resources->bufs,
722 						opts->max_queue_depth *
723 						opts->in_capsule_data_size,
724 						IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
725 	}
726 
727 	if (!resources->cmds_mr || !resources->cpls_mr ||
728 	    (opts->in_capsule_data_size &&
729 	     !resources->bufs_mr)) {
730 		goto cleanup;
731 	}
732 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Command Array: %p Length: %lx LKey: %x\n",
733 		      resources->cmds, opts->max_queue_depth * sizeof(*resources->cmds),
734 		      resources->cmds_mr->lkey);
735 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Completion Array: %p Length: %lx LKey: %x\n",
736 		      resources->cpls, opts->max_queue_depth * sizeof(*resources->cpls),
737 		      resources->cpls_mr->lkey);
738 	if (resources->bufs && resources->bufs_mr) {
739 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "In Capsule Data Array: %p Length: %x LKey: %x\n",
740 			      resources->bufs, opts->max_queue_depth *
741 			      opts->in_capsule_data_size, resources->bufs_mr->lkey);
742 	}
743 
744 	/* Initialize queues */
745 	STAILQ_INIT(&resources->incoming_queue);
746 	STAILQ_INIT(&resources->free_queue);
747 
748 	for (i = 0; i < opts->max_queue_depth; i++) {
749 		struct ibv_recv_wr *bad_wr = NULL;
750 
751 		rdma_recv = &resources->recvs[i];
752 		rdma_recv->qpair = opts->qpair;
753 
754 		/* Set up memory to receive commands */
755 		if (resources->bufs) {
756 			rdma_recv->buf = (void *)((uintptr_t)resources->bufs + (i *
757 						  opts->in_capsule_data_size));
758 		}
759 
760 		rdma_recv->rdma_wr.type = RDMA_WR_TYPE_RECV;
761 
762 		rdma_recv->sgl[0].addr = (uintptr_t)&resources->cmds[i];
763 		rdma_recv->sgl[0].length = sizeof(resources->cmds[i]);
764 		rdma_recv->sgl[0].lkey = resources->cmds_mr->lkey;
765 		rdma_recv->wr.num_sge = 1;
766 
767 		if (rdma_recv->buf && resources->bufs_mr) {
768 			rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
769 			rdma_recv->sgl[1].length = opts->in_capsule_data_size;
770 			rdma_recv->sgl[1].lkey = resources->bufs_mr->lkey;
771 			rdma_recv->wr.num_sge++;
772 		}
773 
774 		rdma_recv->wr.wr_id = (uintptr_t)&rdma_recv->rdma_wr;
775 		rdma_recv->wr.sg_list = rdma_recv->sgl;
776 		if (opts->shared) {
777 			srq = (struct ibv_srq *)opts->qp;
778 			rc = ibv_post_srq_recv(srq, &rdma_recv->wr, &bad_wr);
779 		} else {
780 			qp = (struct ibv_qp *)opts->qp;
781 			rc = ibv_post_recv(qp, &rdma_recv->wr, &bad_wr);
782 		}
783 		if (rc) {
784 			goto cleanup;
785 		}
786 	}
787 
788 	for (i = 0; i < opts->max_queue_depth; i++) {
789 		rdma_req = &resources->reqs[i];
790 
791 		if (opts->qpair != NULL) {
792 			rdma_req->req.qpair = &opts->qpair->qpair;
793 		} else {
794 			rdma_req->req.qpair = NULL;
795 		}
796 		rdma_req->req.cmd = NULL;
797 
798 		/* Set up memory to send responses */
799 		rdma_req->req.rsp = &resources->cpls[i];
800 
801 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&resources->cpls[i];
802 		rdma_req->rsp.sgl[0].length = sizeof(resources->cpls[i]);
803 		rdma_req->rsp.sgl[0].lkey = resources->cpls_mr->lkey;
804 
805 		rdma_req->rsp.rdma_wr.type = RDMA_WR_TYPE_SEND;
806 		rdma_req->rsp.wr.wr_id = (uintptr_t)&rdma_req->rsp.rdma_wr;
807 		rdma_req->rsp.wr.next = NULL;
808 		rdma_req->rsp.wr.opcode = IBV_WR_SEND;
809 		rdma_req->rsp.wr.send_flags = IBV_SEND_SIGNALED;
810 		rdma_req->rsp.wr.sg_list = rdma_req->rsp.sgl;
811 		rdma_req->rsp.wr.num_sge = SPDK_COUNTOF(rdma_req->rsp.sgl);
812 
813 		/* Set up memory for data buffers */
814 		rdma_req->data.rdma_wr.type = RDMA_WR_TYPE_DATA;
815 		rdma_req->data.wr.wr_id = (uintptr_t)&rdma_req->data.rdma_wr;
816 		rdma_req->data.wr.next = NULL;
817 		rdma_req->data.wr.send_flags = IBV_SEND_SIGNALED;
818 		rdma_req->data.wr.sg_list = rdma_req->data.sgl;
819 		rdma_req->data.wr.num_sge = SPDK_COUNTOF(rdma_req->data.sgl);
820 
821 		/* Initialize request state to FREE */
822 		rdma_req->state = RDMA_REQUEST_STATE_FREE;
823 		STAILQ_INSERT_TAIL(&resources->free_queue, rdma_req, state_link);
824 	}
825 
826 	return resources;
827 
828 cleanup:
829 	nvmf_rdma_resources_destroy(resources);
830 	return NULL;
831 }
832 
833 static void
834 nvmf_rdma_qpair_clean_ibv_events(struct spdk_nvmf_rdma_qpair *rqpair)
835 {
836 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx, *tctx;
837 	STAILQ_FOREACH_SAFE(ctx, &rqpair->ibv_events, link, tctx) {
838 		ctx->rqpair = NULL;
839 		/* Memory allocated for ctx is freed in nvmf_rdma_qpair_process_ibv_event */
840 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
841 	}
842 }
843 
844 static void
845 nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
846 {
847 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
848 	struct ibv_recv_wr		*bad_recv_wr = NULL;
849 	int				rc;
850 
851 	spdk_trace_record(TRACE_RDMA_QP_DESTROY, 0, 0, (uintptr_t)rqpair->cm_id, 0);
852 
853 	spdk_poller_unregister(&rqpair->destruct_poller);
854 
855 	if (rqpair->qd != 0) {
856 		struct spdk_nvmf_qpair *qpair = &rqpair->qpair;
857 		struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(qpair->transport,
858 				struct spdk_nvmf_rdma_transport, transport);
859 		struct spdk_nvmf_rdma_request *req;
860 		uint32_t i, max_req_count = 0;
861 
862 		SPDK_WARNLOG("Destroying qpair when queue depth is %d\n", rqpair->qd);
863 
864 		if (rqpair->srq == NULL) {
865 			nvmf_rdma_dump_qpair_contents(rqpair);
866 			max_req_count = rqpair->max_queue_depth;
867 		} else if (rqpair->poller && rqpair->resources) {
868 			max_req_count = rqpair->poller->max_srq_depth;
869 		}
870 
871 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Release incomplete requests\n");
872 		for (i = 0; i < max_req_count; i++) {
873 			req = &rqpair->resources->reqs[i];
874 			if (req->req.qpair == qpair && req->state != RDMA_REQUEST_STATE_FREE) {
875 				/* nvmf_rdma_request_process checks qpair ibv and internal state
876 				 * and completes a request */
877 				nvmf_rdma_request_process(rtransport, req);
878 			}
879 		}
880 		assert(rqpair->qd == 0);
881 	}
882 
883 	if (rqpair->poller) {
884 		TAILQ_REMOVE(&rqpair->poller->qpairs, rqpair, link);
885 
886 		if (rqpair->srq != NULL && rqpair->resources != NULL) {
887 			/* Drop all received but unprocessed commands for this queue and return them to SRQ */
888 			STAILQ_FOREACH_SAFE(rdma_recv, &rqpair->resources->incoming_queue, link, recv_tmp) {
889 				if (rqpair == rdma_recv->qpair) {
890 					STAILQ_REMOVE(&rqpair->resources->incoming_queue, rdma_recv, spdk_nvmf_rdma_recv, link);
891 					rc = ibv_post_srq_recv(rqpair->srq, &rdma_recv->wr, &bad_recv_wr);
892 					if (rc) {
893 						SPDK_ERRLOG("Unable to re-post rx descriptor\n");
894 					}
895 				}
896 			}
897 		}
898 	}
899 
900 	if (rqpair->cm_id) {
901 		if (rqpair->rdma_qp != NULL) {
902 			spdk_rdma_qp_destroy(rqpair->rdma_qp);
903 			rqpair->rdma_qp = NULL;
904 		}
905 		rdma_destroy_id(rqpair->cm_id);
906 
907 		if (rqpair->poller != NULL && rqpair->srq == NULL) {
908 			rqpair->poller->required_num_wr -= MAX_WR_PER_QP(rqpair->max_queue_depth);
909 		}
910 	}
911 
912 	if (rqpair->srq == NULL && rqpair->resources != NULL) {
913 		nvmf_rdma_resources_destroy(rqpair->resources);
914 	}
915 
916 	nvmf_rdma_qpair_clean_ibv_events(rqpair);
917 
918 	if (rqpair->destruct_channel) {
919 		spdk_put_io_channel(rqpair->destruct_channel);
920 		rqpair->destruct_channel = NULL;
921 	}
922 
923 	free(rqpair);
924 }
925 
926 static int
927 nvmf_rdma_resize_cq(struct spdk_nvmf_rdma_qpair *rqpair, struct spdk_nvmf_rdma_device *device)
928 {
929 	struct spdk_nvmf_rdma_poller	*rpoller;
930 	int				rc, num_cqe, required_num_wr;
931 
932 	/* Enlarge CQ size dynamically */
933 	rpoller = rqpair->poller;
934 	required_num_wr = rpoller->required_num_wr + MAX_WR_PER_QP(rqpair->max_queue_depth);
935 	num_cqe = rpoller->num_cqe;
936 	if (num_cqe < required_num_wr) {
937 		num_cqe = spdk_max(num_cqe * 2, required_num_wr);
938 		num_cqe = spdk_min(num_cqe, device->attr.max_cqe);
939 	}
940 
941 	if (rpoller->num_cqe != num_cqe) {
942 		if (required_num_wr > device->attr.max_cqe) {
943 			SPDK_ERRLOG("RDMA CQE requirement (%d) exceeds device max_cqe limitation (%d)\n",
944 				    required_num_wr, device->attr.max_cqe);
945 			return -1;
946 		}
947 
948 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Resize RDMA CQ from %d to %d\n", rpoller->num_cqe, num_cqe);
949 		rc = ibv_resize_cq(rpoller->cq, num_cqe);
950 		if (rc) {
951 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
952 			return -1;
953 		}
954 
955 		rpoller->num_cqe = num_cqe;
956 	}
957 
958 	rpoller->required_num_wr = required_num_wr;
959 	return 0;
960 }
961 
962 static int
963 nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
964 {
965 	struct spdk_nvmf_rdma_qpair		*rqpair;
966 	struct spdk_nvmf_rdma_transport		*rtransport;
967 	struct spdk_nvmf_transport		*transport;
968 	struct spdk_nvmf_rdma_resource_opts	opts;
969 	struct spdk_nvmf_rdma_device		*device;
970 	struct spdk_rdma_qp_init_attr		qp_init_attr = {};
971 
972 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
973 	device = rqpair->device;
974 
975 	qp_init_attr.qp_context	= rqpair;
976 	qp_init_attr.pd		= device->pd;
977 	qp_init_attr.send_cq	= rqpair->poller->cq;
978 	qp_init_attr.recv_cq	= rqpair->poller->cq;
979 
980 	if (rqpair->srq) {
981 		qp_init_attr.srq		= rqpair->srq;
982 	} else {
983 		qp_init_attr.cap.max_recv_wr	= rqpair->max_queue_depth;
984 	}
985 
986 	/* SEND, READ, and WRITE operations */
987 	qp_init_attr.cap.max_send_wr	= (uint32_t)rqpair->max_queue_depth * 2;
988 	qp_init_attr.cap.max_send_sge	= spdk_min((uint32_t)device->attr.max_sge, NVMF_DEFAULT_TX_SGE);
989 	qp_init_attr.cap.max_recv_sge	= spdk_min((uint32_t)device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
990 
991 	if (rqpair->srq == NULL && nvmf_rdma_resize_cq(rqpair, device) < 0) {
992 		SPDK_ERRLOG("Failed to resize the completion queue. Cannot initialize qpair.\n");
993 		goto error;
994 	}
995 
996 	rqpair->rdma_qp = spdk_rdma_qp_create(rqpair->cm_id, &qp_init_attr);
997 	if (!rqpair->rdma_qp) {
998 		goto error;
999 	}
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->cm_id, 0);
1006 	SPDK_DEBUGLOG(SPDK_LOG_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->qp;
1013 		opts.pd = rqpair->cm_id->pd;
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 
1034 	return 0;
1035 
1036 error:
1037 	rdma_destroy_id(rqpair->cm_id);
1038 	rqpair->cm_id = NULL;
1039 	return -1;
1040 }
1041 
1042 /* Append the given recv wr structure to the resource structs outstanding recvs list. */
1043 /* This function accepts either a single wr or the first wr in a linked list. */
1044 static void
1045 nvmf_rdma_qpair_queue_recv_wrs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *first)
1046 {
1047 	struct ibv_recv_wr *last;
1048 
1049 	last = first;
1050 	while (last->next != NULL) {
1051 		last = last->next;
1052 	}
1053 
1054 	if (rqpair->resources->recvs_to_post.first == NULL) {
1055 		rqpair->resources->recvs_to_post.first = first;
1056 		rqpair->resources->recvs_to_post.last = last;
1057 		if (rqpair->srq == NULL) {
1058 			STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_recv, rqpair, recv_link);
1059 		}
1060 	} else {
1061 		rqpair->resources->recvs_to_post.last->next = first;
1062 		rqpair->resources->recvs_to_post.last = last;
1063 	}
1064 }
1065 
1066 static int
1067 request_transfer_in(struct spdk_nvmf_request *req)
1068 {
1069 	struct spdk_nvmf_rdma_request	*rdma_req;
1070 	struct spdk_nvmf_qpair		*qpair;
1071 	struct spdk_nvmf_rdma_qpair	*rqpair;
1072 
1073 	qpair = req->qpair;
1074 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1075 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1076 
1077 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
1078 	assert(rdma_req != NULL);
1079 
1080 	if (spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, &rdma_req->data.wr)) {
1081 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1082 	}
1083 
1084 	rqpair->current_read_depth += rdma_req->num_outstanding_data_wr;
1085 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr;
1086 	return 0;
1087 }
1088 
1089 static int
1090 request_transfer_out(struct spdk_nvmf_request *req, int *data_posted)
1091 {
1092 	int				num_outstanding_data_wr = 0;
1093 	struct spdk_nvmf_rdma_request	*rdma_req;
1094 	struct spdk_nvmf_qpair		*qpair;
1095 	struct spdk_nvmf_rdma_qpair	*rqpair;
1096 	struct spdk_nvme_cpl		*rsp;
1097 	struct ibv_send_wr		*first = NULL;
1098 
1099 	*data_posted = 0;
1100 	qpair = req->qpair;
1101 	rsp = &req->rsp->nvme_cpl;
1102 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1103 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1104 
1105 	/* Advance our sq_head pointer */
1106 	if (qpair->sq_head == qpair->sq_head_max) {
1107 		qpair->sq_head = 0;
1108 	} else {
1109 		qpair->sq_head++;
1110 	}
1111 	rsp->sqhd = qpair->sq_head;
1112 
1113 	/* queue the capsule for the recv buffer */
1114 	assert(rdma_req->recv != NULL);
1115 
1116 	nvmf_rdma_qpair_queue_recv_wrs(rqpair, &rdma_req->recv->wr);
1117 
1118 	rdma_req->recv = NULL;
1119 	assert(rqpair->current_recv_depth > 0);
1120 	rqpair->current_recv_depth--;
1121 
1122 	/* Build the response which consists of optional
1123 	 * RDMA WRITEs to transfer data, plus an RDMA SEND
1124 	 * containing the response.
1125 	 */
1126 	first = &rdma_req->rsp.wr;
1127 
1128 	if (rsp->status.sc != SPDK_NVME_SC_SUCCESS) {
1129 		/* On failure, data was not read from the controller. So clear the
1130 		 * number of outstanding data WRs to zero.
1131 		 */
1132 		rdma_req->num_outstanding_data_wr = 0;
1133 	} else if (req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1134 		first = &rdma_req->data.wr;
1135 		*data_posted = 1;
1136 		num_outstanding_data_wr = rdma_req->num_outstanding_data_wr;
1137 	}
1138 	if (spdk_rdma_qp_queue_send_wrs(rqpair->rdma_qp, first)) {
1139 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1140 	}
1141 
1142 	/* +1 for the rsp wr */
1143 	rqpair->current_send_depth += num_outstanding_data_wr + 1;
1144 
1145 	return 0;
1146 }
1147 
1148 static int
1149 nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
1150 {
1151 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
1152 	struct rdma_conn_param				ctrlr_event_data = {};
1153 	int						rc;
1154 
1155 	accept_data.recfmt = 0;
1156 	accept_data.crqsize = rqpair->max_queue_depth;
1157 
1158 	ctrlr_event_data.private_data = &accept_data;
1159 	ctrlr_event_data.private_data_len = sizeof(accept_data);
1160 	if (id->ps == RDMA_PS_TCP) {
1161 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
1162 		ctrlr_event_data.initiator_depth = rqpair->max_read_depth;
1163 	}
1164 
1165 	/* Configure infinite retries for the initiator side qpair.
1166 	 * When using a shared receive queue on the target side,
1167 	 * we need to pass this value to the initiator to prevent the
1168 	 * initiator side NIC from completing SEND requests back to the
1169 	 * initiator with status rnr_retry_count_exceeded. */
1170 	if (rqpair->srq != NULL) {
1171 		ctrlr_event_data.rnr_retry_count = 0x7;
1172 	}
1173 
1174 	/* When qpair is created without use of rdma cm API, an additional
1175 	 * information must be provided to initiator in the connection response:
1176 	 * whether qpair is using SRQ and its qp_num
1177 	 * Fields below are ignored by rdma cm if qpair has been
1178 	 * created using rdma cm API. */
1179 	ctrlr_event_data.srq = rqpair->srq ? 1 : 0;
1180 	ctrlr_event_data.qp_num = rqpair->rdma_qp->qp->qp_num;
1181 
1182 	rc = spdk_rdma_qp_accept(rqpair->rdma_qp, &ctrlr_event_data);
1183 	if (rc) {
1184 		SPDK_ERRLOG("Error %d on spdk_rdma_qp_accept\n", errno);
1185 	} else {
1186 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Sent back the accept\n");
1187 	}
1188 
1189 	return rc;
1190 }
1191 
1192 static void
1193 nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
1194 {
1195 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
1196 
1197 	rej_data.recfmt = 0;
1198 	rej_data.sts = error;
1199 
1200 	rdma_reject(id, &rej_data, sizeof(rej_data));
1201 }
1202 
1203 static int
1204 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event)
1205 {
1206 	struct spdk_nvmf_rdma_transport *rtransport;
1207 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
1208 	struct spdk_nvmf_rdma_port	*port;
1209 	struct rdma_conn_param		*rdma_param = NULL;
1210 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
1211 	uint16_t			max_queue_depth;
1212 	uint16_t			max_read_depth;
1213 
1214 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1215 
1216 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
1217 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
1218 
1219 	rdma_param = &event->param.conn;
1220 	if (rdma_param->private_data == NULL ||
1221 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1222 		SPDK_ERRLOG("connect request: no private data provided\n");
1223 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
1224 		return -1;
1225 	}
1226 
1227 	private_data = rdma_param->private_data;
1228 	if (private_data->recfmt != 0) {
1229 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
1230 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
1231 		return -1;
1232 	}
1233 
1234 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Connect Recv on fabric intf name %s, dev_name %s\n",
1235 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
1236 
1237 	port = event->listen_id->context;
1238 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
1239 		      event->listen_id, event->listen_id->verbs, port);
1240 
1241 	/* Figure out the supported queue depth. This is a multi-step process
1242 	 * that takes into account hardware maximums, host provided values,
1243 	 * and our target's internal memory limits */
1244 
1245 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Calculating Queue Depth\n");
1246 
1247 	/* Start with the maximum queue depth allowed by the target */
1248 	max_queue_depth = rtransport->transport.opts.max_queue_depth;
1249 	max_read_depth = rtransport->transport.opts.max_queue_depth;
1250 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Target Max Queue Depth: %d\n",
1251 		      rtransport->transport.opts.max_queue_depth);
1252 
1253 	/* Next check the local NIC's hardware limitations */
1254 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
1255 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
1256 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
1257 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
1258 	max_read_depth = spdk_min(max_read_depth, port->device->attr.max_qp_init_rd_atom);
1259 
1260 	/* Next check the remote NIC's hardware limitations */
1261 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
1262 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
1263 		      rdma_param->initiator_depth, rdma_param->responder_resources);
1264 	if (rdma_param->initiator_depth > 0) {
1265 		max_read_depth = spdk_min(max_read_depth, rdma_param->initiator_depth);
1266 	}
1267 
1268 	/* Finally check for the host software requested values, which are
1269 	 * optional. */
1270 	if (rdma_param->private_data != NULL &&
1271 	    rdma_param->private_data_len >= sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1272 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1273 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Send Queue Size: %d\n", private_data->hsqsize);
1274 		max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
1275 		max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
1276 	}
1277 
1278 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
1279 		      max_queue_depth, max_read_depth);
1280 
1281 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
1282 	if (rqpair == NULL) {
1283 		SPDK_ERRLOG("Could not allocate new connection.\n");
1284 		nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1285 		return -1;
1286 	}
1287 
1288 	rqpair->device = port->device;
1289 	rqpair->max_queue_depth = max_queue_depth;
1290 	rqpair->max_read_depth = max_read_depth;
1291 	rqpair->cm_id = event->id;
1292 	rqpair->listen_id = event->listen_id;
1293 	rqpair->qpair.transport = transport;
1294 	STAILQ_INIT(&rqpair->ibv_events);
1295 	/* use qid from the private data to determine the qpair type
1296 	   qid will be set to the appropriate value when the controller is created */
1297 	rqpair->qpair.qid = private_data->qid;
1298 
1299 	event->id->context = &rqpair->qpair;
1300 
1301 	spdk_nvmf_tgt_new_qpair(transport->tgt, &rqpair->qpair);
1302 
1303 	return 0;
1304 }
1305 
1306 static int
1307 nvmf_rdma_mem_notify(void *cb_ctx, struct spdk_mem_map *map,
1308 		     enum spdk_mem_map_notify_action action,
1309 		     void *vaddr, size_t size)
1310 {
1311 	struct ibv_pd *pd = cb_ctx;
1312 	struct ibv_mr *mr;
1313 	int rc;
1314 
1315 	switch (action) {
1316 	case SPDK_MEM_MAP_NOTIFY_REGISTER:
1317 		if (!g_nvmf_hooks.get_rkey) {
1318 			mr = ibv_reg_mr(pd, vaddr, size,
1319 					IBV_ACCESS_LOCAL_WRITE |
1320 					IBV_ACCESS_REMOTE_READ |
1321 					IBV_ACCESS_REMOTE_WRITE);
1322 			if (mr == NULL) {
1323 				SPDK_ERRLOG("ibv_reg_mr() failed\n");
1324 				return -1;
1325 			} else {
1326 				rc = spdk_mem_map_set_translation(map, (uint64_t)vaddr, size, (uint64_t)mr);
1327 			}
1328 		} else {
1329 			rc = spdk_mem_map_set_translation(map, (uint64_t)vaddr, size,
1330 							  g_nvmf_hooks.get_rkey(pd, vaddr, size));
1331 		}
1332 		break;
1333 	case SPDK_MEM_MAP_NOTIFY_UNREGISTER:
1334 		if (!g_nvmf_hooks.get_rkey) {
1335 			mr = (struct ibv_mr *)spdk_mem_map_translate(map, (uint64_t)vaddr, NULL);
1336 			if (mr) {
1337 				ibv_dereg_mr(mr);
1338 			}
1339 		}
1340 		rc = spdk_mem_map_clear_translation(map, (uint64_t)vaddr, size);
1341 		break;
1342 	default:
1343 		SPDK_UNREACHABLE();
1344 	}
1345 
1346 	return rc;
1347 }
1348 
1349 static int
1350 nvmf_rdma_check_contiguous_entries(uint64_t addr_1, uint64_t addr_2)
1351 {
1352 	/* Two contiguous mappings will point to the same address which is the start of the RDMA MR. */
1353 	return addr_1 == addr_2;
1354 }
1355 
1356 static inline void
1357 nvmf_rdma_setup_wr(struct ibv_send_wr *wr, struct ibv_send_wr *next,
1358 		   enum spdk_nvme_data_transfer xfer)
1359 {
1360 	if (xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1361 		wr->opcode = IBV_WR_RDMA_WRITE;
1362 		wr->send_flags = 0;
1363 		wr->next = next;
1364 	} else if (xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1365 		wr->opcode = IBV_WR_RDMA_READ;
1366 		wr->send_flags = IBV_SEND_SIGNALED;
1367 		wr->next = NULL;
1368 	} else {
1369 		assert(0);
1370 	}
1371 }
1372 
1373 static int
1374 nvmf_request_alloc_wrs(struct spdk_nvmf_rdma_transport *rtransport,
1375 		       struct spdk_nvmf_rdma_request *rdma_req,
1376 		       uint32_t num_sgl_descriptors)
1377 {
1378 	struct spdk_nvmf_rdma_request_data	*work_requests[SPDK_NVMF_MAX_SGL_ENTRIES];
1379 	struct spdk_nvmf_rdma_request_data	*current_data_wr;
1380 	uint32_t				i;
1381 
1382 	if (num_sgl_descriptors > SPDK_NVMF_MAX_SGL_ENTRIES) {
1383 		SPDK_ERRLOG("Requested too much entries (%u), the limit is %u\n",
1384 			    num_sgl_descriptors, SPDK_NVMF_MAX_SGL_ENTRIES);
1385 		return -EINVAL;
1386 	}
1387 
1388 	if (spdk_mempool_get_bulk(rtransport->data_wr_pool, (void **)work_requests, num_sgl_descriptors)) {
1389 		return -ENOMEM;
1390 	}
1391 
1392 	current_data_wr = &rdma_req->data;
1393 
1394 	for (i = 0; i < num_sgl_descriptors; i++) {
1395 		nvmf_rdma_setup_wr(&current_data_wr->wr, &work_requests[i]->wr, rdma_req->req.xfer);
1396 		current_data_wr->wr.next = &work_requests[i]->wr;
1397 		current_data_wr = work_requests[i];
1398 		current_data_wr->wr.sg_list = current_data_wr->sgl;
1399 		current_data_wr->wr.wr_id = rdma_req->data.wr.wr_id;
1400 	}
1401 
1402 	nvmf_rdma_setup_wr(&current_data_wr->wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1403 
1404 	return 0;
1405 }
1406 
1407 static inline void
1408 nvmf_rdma_setup_request(struct spdk_nvmf_rdma_request *rdma_req)
1409 {
1410 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1411 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1412 
1413 	wr->wr.rdma.rkey = sgl->keyed.key;
1414 	wr->wr.rdma.remote_addr = sgl->address;
1415 	nvmf_rdma_setup_wr(wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1416 }
1417 
1418 static inline void
1419 nvmf_rdma_update_remote_addr(struct spdk_nvmf_rdma_request *rdma_req, uint32_t num_wrs)
1420 {
1421 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1422 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1423 	uint32_t			i;
1424 	int				j;
1425 	uint64_t			remote_addr_offset = 0;
1426 
1427 	for (i = 0; i < num_wrs; ++i) {
1428 		wr->wr.rdma.rkey = sgl->keyed.key;
1429 		wr->wr.rdma.remote_addr = sgl->address + remote_addr_offset;
1430 		for (j = 0; j < wr->num_sge; ++j) {
1431 			remote_addr_offset += wr->sg_list[j].length;
1432 		}
1433 		wr = wr->next;
1434 	}
1435 }
1436 
1437 /* This function is used in the rare case that we have a buffer split over multiple memory regions. */
1438 static int
1439 nvmf_rdma_replace_buffer(struct spdk_nvmf_rdma_poll_group *rgroup, void **buf)
1440 {
1441 	struct spdk_nvmf_transport_poll_group	*group = &rgroup->group;
1442 	struct spdk_nvmf_transport		*transport = group->transport;
1443 	struct spdk_nvmf_transport_pg_cache_buf	*old_buf;
1444 	void					*new_buf;
1445 
1446 	if (!(STAILQ_EMPTY(&group->buf_cache))) {
1447 		group->buf_cache_count--;
1448 		new_buf = STAILQ_FIRST(&group->buf_cache);
1449 		STAILQ_REMOVE_HEAD(&group->buf_cache, link);
1450 		assert(*buf != NULL);
1451 	} else {
1452 		new_buf = spdk_mempool_get(transport->data_buf_pool);
1453 	}
1454 
1455 	if (*buf == NULL) {
1456 		return -ENOMEM;
1457 	}
1458 
1459 	old_buf = *buf;
1460 	STAILQ_INSERT_HEAD(&rgroup->retired_bufs, old_buf, link);
1461 	*buf = new_buf;
1462 	return 0;
1463 }
1464 
1465 static bool
1466 nvmf_rdma_get_lkey(struct spdk_nvmf_rdma_device *device, struct iovec *iov,
1467 		   uint32_t *_lkey)
1468 {
1469 	uint64_t	translation_len;
1470 	uint32_t	lkey;
1471 
1472 	translation_len = iov->iov_len;
1473 
1474 	if (!g_nvmf_hooks.get_rkey) {
1475 		lkey = ((struct ibv_mr *)spdk_mem_map_translate(device->map,
1476 				(uint64_t)iov->iov_base, &translation_len))->lkey;
1477 	} else {
1478 		lkey = spdk_mem_map_translate(device->map,
1479 					      (uint64_t)iov->iov_base, &translation_len);
1480 	}
1481 
1482 	if (spdk_unlikely(translation_len < iov->iov_len)) {
1483 		return false;
1484 	}
1485 
1486 	*_lkey = lkey;
1487 	return true;
1488 }
1489 
1490 static bool
1491 nvmf_rdma_fill_wr_sge(struct spdk_nvmf_rdma_device *device,
1492 		      struct iovec *iov, struct ibv_send_wr **_wr,
1493 		      uint32_t *_remaining_data_block, uint32_t *_offset,
1494 		      uint32_t *_num_extra_wrs,
1495 		      const struct spdk_dif_ctx *dif_ctx)
1496 {
1497 	struct ibv_send_wr *wr = *_wr;
1498 	struct ibv_sge	*sg_ele = &wr->sg_list[wr->num_sge];
1499 	uint32_t	lkey = 0;
1500 	uint32_t	remaining, data_block_size, md_size, sge_len;
1501 
1502 	if (spdk_unlikely(!nvmf_rdma_get_lkey(device, iov, &lkey))) {
1503 		/* This is a very rare case that can occur when using DPDK version < 19.05 */
1504 		SPDK_ERRLOG("Data buffer split over multiple RDMA Memory Regions. Removing it from circulation.\n");
1505 		return false;
1506 	}
1507 
1508 	if (spdk_likely(!dif_ctx)) {
1509 		sg_ele->lkey = lkey;
1510 		sg_ele->addr = (uintptr_t)(iov->iov_base);
1511 		sg_ele->length = iov->iov_len;
1512 		wr->num_sge++;
1513 	} else {
1514 		remaining = iov->iov_len - *_offset;
1515 		data_block_size = dif_ctx->block_size - dif_ctx->md_size;
1516 		md_size = dif_ctx->md_size;
1517 
1518 		while (remaining) {
1519 			if (wr->num_sge >= SPDK_NVMF_MAX_SGL_ENTRIES) {
1520 				if (*_num_extra_wrs > 0 && wr->next) {
1521 					*_wr = wr->next;
1522 					wr = *_wr;
1523 					wr->num_sge = 0;
1524 					sg_ele = &wr->sg_list[wr->num_sge];
1525 					(*_num_extra_wrs)--;
1526 				} else {
1527 					break;
1528 				}
1529 			}
1530 			sg_ele->lkey = lkey;
1531 			sg_ele->addr = (uintptr_t)((char *)iov->iov_base + *_offset);
1532 			sge_len = spdk_min(remaining, *_remaining_data_block);
1533 			sg_ele->length = sge_len;
1534 			remaining -= sge_len;
1535 			*_remaining_data_block -= sge_len;
1536 			*_offset += sge_len;
1537 
1538 			sg_ele++;
1539 			wr->num_sge++;
1540 
1541 			if (*_remaining_data_block == 0) {
1542 				/* skip metadata */
1543 				*_offset += md_size;
1544 				/* Metadata that do not fit this IO buffer will be included in the next IO buffer */
1545 				remaining -= spdk_min(remaining, md_size);
1546 				*_remaining_data_block = data_block_size;
1547 			}
1548 
1549 			if (remaining == 0) {
1550 				/* By subtracting the size of the last IOV from the offset, we ensure that we skip
1551 				   the remaining metadata bits at the beginning of the next buffer */
1552 				*_offset -= iov->iov_len;
1553 			}
1554 		}
1555 	}
1556 
1557 	return true;
1558 }
1559 
1560 static int
1561 nvmf_rdma_fill_wr_sgl(struct spdk_nvmf_rdma_poll_group *rgroup,
1562 		      struct spdk_nvmf_rdma_device *device,
1563 		      struct spdk_nvmf_rdma_request *rdma_req,
1564 		      struct ibv_send_wr *wr,
1565 		      uint32_t length,
1566 		      uint32_t num_extra_wrs)
1567 {
1568 	struct spdk_nvmf_request *req = &rdma_req->req;
1569 	struct spdk_dif_ctx *dif_ctx = NULL;
1570 	uint32_t remaining_data_block = 0;
1571 	uint32_t offset = 0;
1572 
1573 	if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
1574 		dif_ctx = &rdma_req->req.dif.dif_ctx;
1575 		remaining_data_block = dif_ctx->block_size - dif_ctx->md_size;
1576 	}
1577 
1578 	wr->num_sge = 0;
1579 
1580 	while (length && (num_extra_wrs || wr->num_sge < SPDK_NVMF_MAX_SGL_ENTRIES)) {
1581 		while (spdk_unlikely(!nvmf_rdma_fill_wr_sge(device, &req->iov[rdma_req->iovpos], &wr,
1582 				     &remaining_data_block, &offset, &num_extra_wrs, dif_ctx))) {
1583 			if (nvmf_rdma_replace_buffer(rgroup, &req->buffers[rdma_req->iovpos]) == -ENOMEM) {
1584 				return -ENOMEM;
1585 			}
1586 			req->iov[rdma_req->iovpos].iov_base = (void *)((uintptr_t)(req->buffers[rdma_req->iovpos] +
1587 							      NVMF_DATA_BUFFER_MASK) &
1588 							      ~NVMF_DATA_BUFFER_MASK);
1589 		}
1590 
1591 		length -= req->iov[rdma_req->iovpos].iov_len;
1592 		rdma_req->iovpos++;
1593 	}
1594 
1595 	if (length) {
1596 		SPDK_ERRLOG("Not enough SG entries to hold data buffer\n");
1597 		return -EINVAL;
1598 	}
1599 
1600 	return 0;
1601 }
1602 
1603 static inline uint32_t
1604 nvmf_rdma_calc_num_wrs(uint32_t length, uint32_t io_unit_size, uint32_t block_size)
1605 {
1606 	/* estimate the number of SG entries and WRs needed to process the request */
1607 	uint32_t num_sge = 0;
1608 	uint32_t i;
1609 	uint32_t num_buffers = SPDK_CEIL_DIV(length, io_unit_size);
1610 
1611 	for (i = 0; i < num_buffers && length > 0; i++) {
1612 		uint32_t buffer_len = spdk_min(length, io_unit_size);
1613 		uint32_t num_sge_in_block = SPDK_CEIL_DIV(buffer_len, block_size);
1614 
1615 		if (num_sge_in_block * block_size > buffer_len) {
1616 			++num_sge_in_block;
1617 		}
1618 		num_sge += num_sge_in_block;
1619 		length -= buffer_len;
1620 	}
1621 	return SPDK_CEIL_DIV(num_sge, SPDK_NVMF_MAX_SGL_ENTRIES);
1622 }
1623 
1624 static int
1625 nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1626 			    struct spdk_nvmf_rdma_device *device,
1627 			    struct spdk_nvmf_rdma_request *rdma_req,
1628 			    uint32_t length)
1629 {
1630 	struct spdk_nvmf_rdma_qpair		*rqpair;
1631 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1632 	struct spdk_nvmf_request		*req = &rdma_req->req;
1633 	struct ibv_send_wr			*wr = &rdma_req->data.wr;
1634 	int					rc;
1635 	uint32_t				num_wrs = 1;
1636 
1637 	rqpair = SPDK_CONTAINEROF(req->qpair, struct spdk_nvmf_rdma_qpair, qpair);
1638 	rgroup = rqpair->poller->group;
1639 
1640 	/* rdma wr specifics */
1641 	nvmf_rdma_setup_request(rdma_req);
1642 
1643 	rc = spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport,
1644 					   length);
1645 	if (rc != 0) {
1646 		return rc;
1647 	}
1648 
1649 	assert(req->iovcnt <= rqpair->max_send_sge);
1650 
1651 	rdma_req->iovpos = 0;
1652 
1653 	if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1654 		num_wrs = nvmf_rdma_calc_num_wrs(length, rtransport->transport.opts.io_unit_size,
1655 						 req->dif.dif_ctx.block_size);
1656 		if (num_wrs > 1) {
1657 			rc = nvmf_request_alloc_wrs(rtransport, rdma_req, num_wrs - 1);
1658 			if (rc != 0) {
1659 				goto err_exit;
1660 			}
1661 		}
1662 	}
1663 
1664 	rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, wr, length, num_wrs - 1);
1665 	if (spdk_unlikely(rc != 0)) {
1666 		goto err_exit;
1667 	}
1668 
1669 	if (spdk_unlikely(num_wrs > 1)) {
1670 		nvmf_rdma_update_remote_addr(rdma_req, num_wrs);
1671 	}
1672 
1673 	/* set the number of outstanding data WRs for this request. */
1674 	rdma_req->num_outstanding_data_wr = num_wrs;
1675 
1676 	return rc;
1677 
1678 err_exit:
1679 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1680 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1681 	req->iovcnt = 0;
1682 	return rc;
1683 }
1684 
1685 static int
1686 nvmf_rdma_request_fill_iovs_multi_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1687 				      struct spdk_nvmf_rdma_device *device,
1688 				      struct spdk_nvmf_rdma_request *rdma_req)
1689 {
1690 	struct spdk_nvmf_rdma_qpair		*rqpair;
1691 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1692 	struct ibv_send_wr			*current_wr;
1693 	struct spdk_nvmf_request		*req = &rdma_req->req;
1694 	struct spdk_nvme_sgl_descriptor		*inline_segment, *desc;
1695 	uint32_t				num_sgl_descriptors;
1696 	uint32_t				lengths[SPDK_NVMF_MAX_SGL_ENTRIES];
1697 	uint32_t				i;
1698 	int					rc;
1699 
1700 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1701 	rgroup = rqpair->poller->group;
1702 
1703 	inline_segment = &req->cmd->nvme_cmd.dptr.sgl1;
1704 	assert(inline_segment->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT);
1705 	assert(inline_segment->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET);
1706 
1707 	num_sgl_descriptors = inline_segment->unkeyed.length / sizeof(struct spdk_nvme_sgl_descriptor);
1708 	assert(num_sgl_descriptors <= SPDK_NVMF_MAX_SGL_ENTRIES);
1709 
1710 	if (nvmf_request_alloc_wrs(rtransport, rdma_req, num_sgl_descriptors - 1) != 0) {
1711 		return -ENOMEM;
1712 	}
1713 
1714 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1715 	for (i = 0; i < num_sgl_descriptors; i++) {
1716 		if (spdk_likely(!req->dif.dif_insert_or_strip)) {
1717 			lengths[i] = desc->keyed.length;
1718 		} else {
1719 			req->dif.orig_length += desc->keyed.length;
1720 			lengths[i] = spdk_dif_get_length_with_md(desc->keyed.length, &req->dif.dif_ctx);
1721 			req->dif.elba_length += lengths[i];
1722 		}
1723 		desc++;
1724 	}
1725 
1726 	rc = spdk_nvmf_request_get_buffers_multi(req, &rgroup->group, &rtransport->transport,
1727 			lengths, num_sgl_descriptors);
1728 	if (rc != 0) {
1729 		nvmf_rdma_request_free_data(rdma_req, rtransport);
1730 		return rc;
1731 	}
1732 
1733 	/* The first WR must always be the embedded data WR. This is how we unwind them later. */
1734 	current_wr = &rdma_req->data.wr;
1735 	assert(current_wr != NULL);
1736 
1737 	req->length = 0;
1738 	rdma_req->iovpos = 0;
1739 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1740 	for (i = 0; i < num_sgl_descriptors; i++) {
1741 		/* The descriptors must be keyed data block descriptors with an address, not an offset. */
1742 		if (spdk_unlikely(desc->generic.type != SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK ||
1743 				  desc->keyed.subtype != SPDK_NVME_SGL_SUBTYPE_ADDRESS)) {
1744 			rc = -EINVAL;
1745 			goto err_exit;
1746 		}
1747 
1748 		current_wr->num_sge = 0;
1749 
1750 		rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, current_wr, lengths[i], 0);
1751 		if (rc != 0) {
1752 			rc = -ENOMEM;
1753 			goto err_exit;
1754 		}
1755 
1756 		req->length += desc->keyed.length;
1757 		current_wr->wr.rdma.rkey = desc->keyed.key;
1758 		current_wr->wr.rdma.remote_addr = desc->address;
1759 		current_wr = current_wr->next;
1760 		desc++;
1761 	}
1762 
1763 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1764 	/* Go back to the last descriptor in the list. */
1765 	desc--;
1766 	if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1767 		if (desc->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1768 			rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1769 			rdma_req->rsp.wr.imm_data = desc->keyed.key;
1770 		}
1771 	}
1772 #endif
1773 
1774 	rdma_req->num_outstanding_data_wr = num_sgl_descriptors;
1775 
1776 	return 0;
1777 
1778 err_exit:
1779 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1780 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1781 	return rc;
1782 }
1783 
1784 static int
1785 nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1786 			    struct spdk_nvmf_rdma_device *device,
1787 			    struct spdk_nvmf_rdma_request *rdma_req)
1788 {
1789 	struct spdk_nvmf_request		*req = &rdma_req->req;
1790 	struct spdk_nvme_cpl			*rsp;
1791 	struct spdk_nvme_sgl_descriptor		*sgl;
1792 	int					rc;
1793 	uint32_t				length;
1794 
1795 	rsp = &req->rsp->nvme_cpl;
1796 	sgl = &req->cmd->nvme_cmd.dptr.sgl1;
1797 
1798 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1799 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1800 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1801 
1802 		length = sgl->keyed.length;
1803 		if (length > rtransport->transport.opts.max_io_size) {
1804 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1805 				    length, rtransport->transport.opts.max_io_size);
1806 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1807 			return -1;
1808 		}
1809 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1810 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1811 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1812 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1813 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1814 			}
1815 		}
1816 #endif
1817 
1818 		/* fill request length and populate iovs */
1819 		req->length = length;
1820 
1821 		if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1822 			req->dif.orig_length = length;
1823 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
1824 			req->dif.elba_length = length;
1825 		}
1826 
1827 		rc = nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req, length);
1828 		if (spdk_unlikely(rc < 0)) {
1829 			if (rc == -EINVAL) {
1830 				SPDK_ERRLOG("SGL length exceeds the max I/O size\n");
1831 				rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1832 				return -1;
1833 			}
1834 			/* No available buffers. Queue this request up. */
1835 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1836 			return 0;
1837 		}
1838 
1839 		/* backward compatible */
1840 		req->data = req->iov[0].iov_base;
1841 
1842 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1843 			      req->iovcnt);
1844 
1845 		return 0;
1846 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1847 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1848 		uint64_t offset = sgl->address;
1849 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1850 
1851 		SPDK_DEBUGLOG(SPDK_LOG_NVMF, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1852 			      offset, sgl->unkeyed.length);
1853 
1854 		if (offset > max_len) {
1855 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1856 				    offset, max_len);
1857 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1858 			return -1;
1859 		}
1860 		max_len -= (uint32_t)offset;
1861 
1862 		if (sgl->unkeyed.length > max_len) {
1863 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1864 				    sgl->unkeyed.length, max_len);
1865 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1866 			return -1;
1867 		}
1868 
1869 		rdma_req->num_outstanding_data_wr = 0;
1870 		req->data = rdma_req->recv->buf + offset;
1871 		req->data_from_pool = false;
1872 		req->length = sgl->unkeyed.length;
1873 
1874 		req->iov[0].iov_base = req->data;
1875 		req->iov[0].iov_len = req->length;
1876 		req->iovcnt = 1;
1877 
1878 		return 0;
1879 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT &&
1880 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1881 
1882 		rc = nvmf_rdma_request_fill_iovs_multi_sgl(rtransport, device, rdma_req);
1883 		if (rc == -ENOMEM) {
1884 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1885 			return 0;
1886 		} else if (rc == -EINVAL) {
1887 			SPDK_ERRLOG("Multi SGL element request length exceeds the max I/O size\n");
1888 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1889 			return -1;
1890 		}
1891 
1892 		/* backward compatible */
1893 		req->data = req->iov[0].iov_base;
1894 
1895 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1896 			      req->iovcnt);
1897 
1898 		return 0;
1899 	}
1900 
1901 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1902 		    sgl->generic.type, sgl->generic.subtype);
1903 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1904 	return -1;
1905 }
1906 
1907 static void
1908 _nvmf_rdma_request_free(struct spdk_nvmf_rdma_request *rdma_req,
1909 			struct spdk_nvmf_rdma_transport	*rtransport)
1910 {
1911 	struct spdk_nvmf_rdma_qpair		*rqpair;
1912 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1913 
1914 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1915 	if (rdma_req->req.data_from_pool) {
1916 		rgroup = rqpair->poller->group;
1917 
1918 		spdk_nvmf_request_free_buffers(&rdma_req->req, &rgroup->group, &rtransport->transport);
1919 	}
1920 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1921 	rdma_req->req.length = 0;
1922 	rdma_req->req.iovcnt = 0;
1923 	rdma_req->req.data = NULL;
1924 	rdma_req->rsp.wr.next = NULL;
1925 	rdma_req->data.wr.next = NULL;
1926 	memset(&rdma_req->req.dif, 0, sizeof(rdma_req->req.dif));
1927 	rqpair->qd--;
1928 
1929 	STAILQ_INSERT_HEAD(&rqpair->resources->free_queue, rdma_req, state_link);
1930 	rdma_req->state = RDMA_REQUEST_STATE_FREE;
1931 }
1932 
1933 bool
1934 nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
1935 			  struct spdk_nvmf_rdma_request *rdma_req)
1936 {
1937 	struct spdk_nvmf_rdma_qpair	*rqpair;
1938 	struct spdk_nvmf_rdma_device	*device;
1939 	struct spdk_nvmf_rdma_poll_group *rgroup;
1940 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
1941 	int				rc;
1942 	struct spdk_nvmf_rdma_recv	*rdma_recv;
1943 	enum spdk_nvmf_rdma_request_state prev_state;
1944 	bool				progress = false;
1945 	int				data_posted;
1946 	uint32_t			num_blocks;
1947 
1948 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1949 	device = rqpair->device;
1950 	rgroup = rqpair->poller->group;
1951 
1952 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
1953 
1954 	/* If the queue pair is in an error state, force the request to the completed state
1955 	 * to release resources. */
1956 	if (rqpair->ibv_state == IBV_QPS_ERR || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1957 		if (rdma_req->state == RDMA_REQUEST_STATE_NEED_BUFFER) {
1958 			STAILQ_REMOVE(&rgroup->group.pending_buf_queue, &rdma_req->req, spdk_nvmf_request, buf_link);
1959 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING) {
1960 			STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1961 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING) {
1962 			STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1963 		}
1964 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1965 	}
1966 
1967 	/* The loop here is to allow for several back-to-back state changes. */
1968 	do {
1969 		prev_state = rdma_req->state;
1970 
1971 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p entering state %d\n", rdma_req, prev_state);
1972 
1973 		switch (rdma_req->state) {
1974 		case RDMA_REQUEST_STATE_FREE:
1975 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
1976 			 * to escape this state. */
1977 			break;
1978 		case RDMA_REQUEST_STATE_NEW:
1979 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
1980 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1981 			rdma_recv = rdma_req->recv;
1982 
1983 			/* The first element of the SGL is the NVMe command */
1984 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
1985 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
1986 
1987 			if (rqpair->ibv_state == IBV_QPS_ERR  || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1988 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1989 				break;
1990 			}
1991 
1992 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&rdma_req->req, &rdma_req->req.dif.dif_ctx))) {
1993 				rdma_req->req.dif.dif_insert_or_strip = true;
1994 			}
1995 
1996 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1997 			rdma_req->rsp.wr.opcode = IBV_WR_SEND;
1998 			rdma_req->rsp.wr.imm_data = 0;
1999 #endif
2000 
2001 			/* The next state transition depends on the data transfer needs of this request. */
2002 			rdma_req->req.xfer = spdk_nvmf_req_get_xfer(&rdma_req->req);
2003 
2004 			/* If no data to transfer, ready to execute. */
2005 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
2006 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
2007 				break;
2008 			}
2009 
2010 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
2011 			STAILQ_INSERT_TAIL(&rgroup->group.pending_buf_queue, &rdma_req->req, buf_link);
2012 			break;
2013 		case RDMA_REQUEST_STATE_NEED_BUFFER:
2014 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
2015 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2016 
2017 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
2018 
2019 			if (&rdma_req->req != STAILQ_FIRST(&rgroup->group.pending_buf_queue)) {
2020 				/* This request needs to wait in line to obtain a buffer */
2021 				break;
2022 			}
2023 
2024 			/* Try to get a data buffer */
2025 			rc = nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
2026 			if (rc < 0) {
2027 				STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2028 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2029 				break;
2030 			}
2031 
2032 			if (!rdma_req->req.data) {
2033 				/* No buffers available. */
2034 				rgroup->stat.pending_data_buffer++;
2035 				break;
2036 			}
2037 
2038 			STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2039 
2040 			/* If data is transferring from host to controller and the data didn't
2041 			 * arrive using in capsule data, we need to do a transfer from the host.
2042 			 */
2043 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER &&
2044 			    rdma_req->req.data_from_pool) {
2045 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
2046 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
2047 				break;
2048 			}
2049 
2050 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
2051 			break;
2052 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
2053 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING, 0, 0,
2054 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2055 
2056 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_read_queue)) {
2057 				/* This request needs to wait in line to perform RDMA */
2058 				break;
2059 			}
2060 			if (rqpair->current_send_depth + rdma_req->num_outstanding_data_wr > rqpair->max_send_depth
2061 			    || rqpair->current_read_depth + rdma_req->num_outstanding_data_wr > rqpair->max_read_depth) {
2062 				/* We can only have so many WRs outstanding. we have to wait until some finish. */
2063 				rqpair->poller->stat.pending_rdma_read++;
2064 				break;
2065 			}
2066 
2067 			/* We have already verified that this request is the head of the queue. */
2068 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_read_queue, state_link);
2069 
2070 			rc = request_transfer_in(&rdma_req->req);
2071 			if (!rc) {
2072 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
2073 			} else {
2074 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
2075 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2076 			}
2077 			break;
2078 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2079 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2080 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2081 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
2082 			 * to escape this state. */
2083 			break;
2084 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
2085 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
2086 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2087 
2088 			if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
2089 				if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2090 					/* generate DIF for write operation */
2091 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2092 					assert(num_blocks > 0);
2093 
2094 					rc = spdk_dif_generate(rdma_req->req.iov, rdma_req->req.iovcnt,
2095 							       num_blocks, &rdma_req->req.dif.dif_ctx);
2096 					if (rc != 0) {
2097 						SPDK_ERRLOG("DIF generation failed\n");
2098 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2099 						nvmf_rdma_start_disconnect(rqpair);
2100 						break;
2101 					}
2102 				}
2103 
2104 				assert(rdma_req->req.dif.elba_length >= rdma_req->req.length);
2105 				/* set extended length before IO operation */
2106 				rdma_req->req.length = rdma_req->req.dif.elba_length;
2107 			}
2108 
2109 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
2110 			spdk_nvmf_request_exec(&rdma_req->req);
2111 			break;
2112 		case RDMA_REQUEST_STATE_EXECUTING:
2113 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
2114 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2115 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
2116 			 * to escape this state. */
2117 			break;
2118 		case RDMA_REQUEST_STATE_EXECUTED:
2119 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
2120 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2121 			if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
2122 			    rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2123 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_write_queue, rdma_req, state_link);
2124 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING;
2125 			} else {
2126 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2127 			}
2128 			if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
2129 				/* restore the original length */
2130 				rdma_req->req.length = rdma_req->req.dif.orig_length;
2131 
2132 				if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2133 					struct spdk_dif_error error_blk;
2134 
2135 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2136 
2137 					rc = spdk_dif_verify(rdma_req->req.iov, rdma_req->req.iovcnt, num_blocks,
2138 							     &rdma_req->req.dif.dif_ctx, &error_blk);
2139 					if (rc) {
2140 						struct spdk_nvme_cpl *rsp = &rdma_req->req.rsp->nvme_cpl;
2141 
2142 						SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n", error_blk.err_type,
2143 							    error_blk.err_offset);
2144 						rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2145 						rsp->status.sc = nvmf_rdma_dif_error_to_compl_status(error_blk.err_type);
2146 						rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2147 						STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2148 					}
2149 				}
2150 			}
2151 			break;
2152 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
2153 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING, 0, 0,
2154 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2155 
2156 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_write_queue)) {
2157 				/* This request needs to wait in line to perform RDMA */
2158 				break;
2159 			}
2160 			if ((rqpair->current_send_depth + rdma_req->num_outstanding_data_wr + 1) >
2161 			    rqpair->max_send_depth) {
2162 				/* We can only have so many WRs outstanding. we have to wait until some finish.
2163 				 * +1 since each request has an additional wr in the resp. */
2164 				rqpair->poller->stat.pending_rdma_write++;
2165 				break;
2166 			}
2167 
2168 			/* We have already verified that this request is the head of the queue. */
2169 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_write_queue, state_link);
2170 
2171 			/* The data transfer will be kicked off from
2172 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
2173 			 */
2174 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2175 			break;
2176 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
2177 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
2178 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2179 			rc = request_transfer_out(&rdma_req->req, &data_posted);
2180 			assert(rc == 0); /* No good way to handle this currently */
2181 			if (rc) {
2182 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2183 			} else {
2184 				rdma_req->state = data_posted ? RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
2185 						  RDMA_REQUEST_STATE_COMPLETING;
2186 			}
2187 			break;
2188 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2189 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2190 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2191 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2192 			 * to escape this state. */
2193 			break;
2194 		case RDMA_REQUEST_STATE_COMPLETING:
2195 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
2196 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2197 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2198 			 * to escape this state. */
2199 			break;
2200 		case RDMA_REQUEST_STATE_COMPLETED:
2201 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
2202 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2203 
2204 			rqpair->poller->stat.request_latency += spdk_get_ticks() - rdma_req->receive_tsc;
2205 			_nvmf_rdma_request_free(rdma_req, rtransport);
2206 			break;
2207 		case RDMA_REQUEST_NUM_STATES:
2208 		default:
2209 			assert(0);
2210 			break;
2211 		}
2212 
2213 		if (rdma_req->state != prev_state) {
2214 			progress = true;
2215 		}
2216 	} while (rdma_req->state != prev_state);
2217 
2218 	return progress;
2219 }
2220 
2221 /* Public API callbacks begin here */
2222 
2223 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
2224 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
2225 #define SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH 4096
2226 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
2227 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2228 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
2229 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
2230 #define SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS 4095
2231 #define SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE 32
2232 #define SPDK_NVMF_RDMA_DEFAULT_NO_SRQ false
2233 #define SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP false
2234 #define SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG 100
2235 #define SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC 1
2236 
2237 static void
2238 nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
2239 {
2240 	opts->max_queue_depth =		SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
2241 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2242 	opts->in_capsule_data_size =	SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
2243 	opts->max_io_size =		SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
2244 	opts->io_unit_size =		SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE;
2245 	opts->max_aq_depth =		SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
2246 	opts->num_shared_buffers =	SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS;
2247 	opts->buf_cache_size =		SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE;
2248 	opts->max_srq_depth =		SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH;
2249 	opts->no_srq =			SPDK_NVMF_RDMA_DEFAULT_NO_SRQ;
2250 	opts->dif_insert_or_strip =	SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP;
2251 	opts->acceptor_backlog =	SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2252 	opts->abort_timeout_sec =	SPDK_NVMF_RDMA_DEFAULT_ABORT_TIMEOUT_SEC;
2253 }
2254 
2255 const struct spdk_mem_map_ops g_nvmf_rdma_map_ops = {
2256 	.notify_cb = nvmf_rdma_mem_notify,
2257 	.are_contiguous = nvmf_rdma_check_contiguous_entries
2258 };
2259 
2260 static int nvmf_rdma_destroy(struct spdk_nvmf_transport *transport);
2261 
2262 static struct spdk_nvmf_transport *
2263 nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
2264 {
2265 	int rc;
2266 	struct spdk_nvmf_rdma_transport *rtransport;
2267 	struct spdk_nvmf_rdma_device	*device, *tmp;
2268 	struct ibv_context		**contexts;
2269 	uint32_t			i;
2270 	int				flag;
2271 	uint32_t			sge_count;
2272 	uint32_t			min_shared_buffers;
2273 	int				max_device_sge = SPDK_NVMF_MAX_SGL_ENTRIES;
2274 	pthread_mutexattr_t		attr;
2275 
2276 	rtransport = calloc(1, sizeof(*rtransport));
2277 	if (!rtransport) {
2278 		return NULL;
2279 	}
2280 
2281 	if (pthread_mutexattr_init(&attr)) {
2282 		SPDK_ERRLOG("pthread_mutexattr_init() failed\n");
2283 		free(rtransport);
2284 		return NULL;
2285 	}
2286 
2287 	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) {
2288 		SPDK_ERRLOG("pthread_mutexattr_settype() failed\n");
2289 		pthread_mutexattr_destroy(&attr);
2290 		free(rtransport);
2291 		return NULL;
2292 	}
2293 
2294 	if (pthread_mutex_init(&rtransport->lock, &attr)) {
2295 		SPDK_ERRLOG("pthread_mutex_init() failed\n");
2296 		pthread_mutexattr_destroy(&attr);
2297 		free(rtransport);
2298 		return NULL;
2299 	}
2300 
2301 	pthread_mutexattr_destroy(&attr);
2302 
2303 	TAILQ_INIT(&rtransport->devices);
2304 	TAILQ_INIT(&rtransport->ports);
2305 	TAILQ_INIT(&rtransport->poll_groups);
2306 
2307 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
2308 
2309 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** RDMA Transport Init ***\n"
2310 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
2311 		     "  max_io_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
2312 		     "  in_capsule_data_size=%d, max_aq_depth=%d,\n"
2313 		     "  num_shared_buffers=%d, max_srq_depth=%d, no_srq=%d,"
2314 		     "  acceptor_backlog=%d, abort_timeout_sec=%d\n",
2315 		     opts->max_queue_depth,
2316 		     opts->max_io_size,
2317 		     opts->max_qpairs_per_ctrlr - 1,
2318 		     opts->io_unit_size,
2319 		     opts->in_capsule_data_size,
2320 		     opts->max_aq_depth,
2321 		     opts->num_shared_buffers,
2322 		     opts->max_srq_depth,
2323 		     opts->no_srq,
2324 		     opts->acceptor_backlog,
2325 		     opts->abort_timeout_sec);
2326 
2327 	/* I/O unit size cannot be larger than max I/O size */
2328 	if (opts->io_unit_size > opts->max_io_size) {
2329 		opts->io_unit_size = opts->max_io_size;
2330 	}
2331 
2332 	if (opts->acceptor_backlog <= 0) {
2333 		SPDK_ERRLOG("The acceptor backlog cannot be less than 1, setting to the default value of (%d).\n",
2334 			    SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG);
2335 		opts->acceptor_backlog = SPDK_NVMF_RDMA_ACCEPTOR_BACKLOG;
2336 	}
2337 
2338 	if (opts->num_shared_buffers < (SPDK_NVMF_MAX_SGL_ENTRIES * 2)) {
2339 		SPDK_ERRLOG("The number of shared data buffers (%d) is less than"
2340 			    "the minimum number required to guarantee that forward progress can be made (%d)\n",
2341 			    opts->num_shared_buffers, (SPDK_NVMF_MAX_SGL_ENTRIES * 2));
2342 		nvmf_rdma_destroy(&rtransport->transport);
2343 		return NULL;
2344 	}
2345 
2346 	min_shared_buffers = spdk_thread_get_count() * opts->buf_cache_size;
2347 	if (min_shared_buffers > opts->num_shared_buffers) {
2348 		SPDK_ERRLOG("There are not enough buffers to satisfy"
2349 			    "per-poll group caches for each thread. (%" PRIu32 ")"
2350 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
2351 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
2352 		nvmf_rdma_destroy(&rtransport->transport);
2353 		return NULL;
2354 	}
2355 
2356 	sge_count = opts->max_io_size / opts->io_unit_size;
2357 	if (sge_count > NVMF_DEFAULT_TX_SGE) {
2358 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
2359 		nvmf_rdma_destroy(&rtransport->transport);
2360 		return NULL;
2361 	}
2362 
2363 	rtransport->event_channel = rdma_create_event_channel();
2364 	if (rtransport->event_channel == NULL) {
2365 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
2366 		nvmf_rdma_destroy(&rtransport->transport);
2367 		return NULL;
2368 	}
2369 
2370 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
2371 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2372 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
2373 			    rtransport->event_channel->fd, spdk_strerror(errno));
2374 		nvmf_rdma_destroy(&rtransport->transport);
2375 		return NULL;
2376 	}
2377 
2378 	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data",
2379 				   opts->max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES,
2380 				   sizeof(struct spdk_nvmf_rdma_request_data),
2381 				   SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
2382 				   SPDK_ENV_SOCKET_ID_ANY);
2383 	if (!rtransport->data_wr_pool) {
2384 		SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");
2385 		nvmf_rdma_destroy(&rtransport->transport);
2386 		return NULL;
2387 	}
2388 
2389 	contexts = rdma_get_devices(NULL);
2390 	if (contexts == NULL) {
2391 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2392 		nvmf_rdma_destroy(&rtransport->transport);
2393 		return NULL;
2394 	}
2395 
2396 	i = 0;
2397 	rc = 0;
2398 	while (contexts[i] != NULL) {
2399 		device = calloc(1, sizeof(*device));
2400 		if (!device) {
2401 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
2402 			rc = -ENOMEM;
2403 			break;
2404 		}
2405 		device->context = contexts[i];
2406 		rc = ibv_query_device(device->context, &device->attr);
2407 		if (rc < 0) {
2408 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2409 			free(device);
2410 			break;
2411 
2412 		}
2413 
2414 		max_device_sge = spdk_min(max_device_sge, device->attr.max_sge);
2415 
2416 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2417 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
2418 			SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
2419 			SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
2420 		}
2421 
2422 		/**
2423 		 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
2424 		 * The Soft-RoCE RXE driver does not currently support send with invalidate,
2425 		 * but incorrectly reports that it does. There are changes making their way
2426 		 * through the kernel now that will enable this feature. When they are merged,
2427 		 * we can conditionally enable this feature.
2428 		 *
2429 		 * TODO: enable this for versions of the kernel rxe driver that support it.
2430 		 */
2431 		if (device->attr.vendor_id == 0) {
2432 			device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
2433 		}
2434 #endif
2435 
2436 		/* set up device context async ev fd as NON_BLOCKING */
2437 		flag = fcntl(device->context->async_fd, F_GETFL);
2438 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
2439 		if (rc < 0) {
2440 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
2441 			free(device);
2442 			break;
2443 		}
2444 
2445 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
2446 		i++;
2447 
2448 		if (g_nvmf_hooks.get_ibv_pd) {
2449 			device->pd = g_nvmf_hooks.get_ibv_pd(NULL, device->context);
2450 		} else {
2451 			device->pd = ibv_alloc_pd(device->context);
2452 		}
2453 
2454 		if (!device->pd) {
2455 			SPDK_ERRLOG("Unable to allocate protection domain.\n");
2456 			rc = -ENOMEM;
2457 			break;
2458 		}
2459 
2460 		assert(device->map == NULL);
2461 
2462 		device->map = spdk_mem_map_alloc(0, &g_nvmf_rdma_map_ops, device->pd);
2463 		if (!device->map) {
2464 			SPDK_ERRLOG("Unable to allocate memory map for listen address\n");
2465 			rc = -ENOMEM;
2466 			break;
2467 		}
2468 
2469 		assert(device->map != NULL);
2470 		assert(device->pd != NULL);
2471 	}
2472 	rdma_free_devices(contexts);
2473 
2474 	if (opts->io_unit_size * max_device_sge < opts->max_io_size) {
2475 		/* divide and round up. */
2476 		opts->io_unit_size = (opts->max_io_size + max_device_sge - 1) / max_device_sge;
2477 
2478 		/* round up to the nearest 4k. */
2479 		opts->io_unit_size = (opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT - 1) & ~NVMF_DATA_BUFFER_MASK;
2480 
2481 		opts->io_unit_size = spdk_max(opts->io_unit_size, SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
2482 		SPDK_NOTICELOG("Adjusting the io unit size to fit the device's maximum I/O size. New I/O unit size %u\n",
2483 			       opts->io_unit_size);
2484 	}
2485 
2486 	if (rc < 0) {
2487 		nvmf_rdma_destroy(&rtransport->transport);
2488 		return NULL;
2489 	}
2490 
2491 	/* Set up poll descriptor array to monitor events from RDMA and IB
2492 	 * in a single poll syscall
2493 	 */
2494 	rtransport->npoll_fds = i + 1;
2495 	i = 0;
2496 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
2497 	if (rtransport->poll_fds == NULL) {
2498 		SPDK_ERRLOG("poll_fds allocation failed\n");
2499 		nvmf_rdma_destroy(&rtransport->transport);
2500 		return NULL;
2501 	}
2502 
2503 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
2504 	rtransport->poll_fds[i++].events = POLLIN;
2505 
2506 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2507 		rtransport->poll_fds[i].fd = device->context->async_fd;
2508 		rtransport->poll_fds[i++].events = POLLIN;
2509 	}
2510 
2511 	return &rtransport->transport;
2512 }
2513 
2514 static int
2515 nvmf_rdma_destroy(struct spdk_nvmf_transport *transport)
2516 {
2517 	struct spdk_nvmf_rdma_transport	*rtransport;
2518 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
2519 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
2520 
2521 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2522 
2523 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
2524 		TAILQ_REMOVE(&rtransport->ports, port, link);
2525 		rdma_destroy_id(port->id);
2526 		free(port);
2527 	}
2528 
2529 	if (rtransport->poll_fds != NULL) {
2530 		free(rtransport->poll_fds);
2531 	}
2532 
2533 	if (rtransport->event_channel != NULL) {
2534 		rdma_destroy_event_channel(rtransport->event_channel);
2535 	}
2536 
2537 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
2538 		TAILQ_REMOVE(&rtransport->devices, device, link);
2539 		if (device->map) {
2540 			spdk_mem_map_free(&device->map);
2541 		}
2542 		if (device->pd) {
2543 			if (!g_nvmf_hooks.get_ibv_pd) {
2544 				ibv_dealloc_pd(device->pd);
2545 			}
2546 		}
2547 		free(device);
2548 	}
2549 
2550 	if (rtransport->data_wr_pool != NULL) {
2551 		if (spdk_mempool_count(rtransport->data_wr_pool) !=
2552 		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {
2553 			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",
2554 				    spdk_mempool_count(rtransport->data_wr_pool),
2555 				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);
2556 		}
2557 	}
2558 
2559 	spdk_mempool_free(rtransport->data_wr_pool);
2560 
2561 	pthread_mutex_destroy(&rtransport->lock);
2562 	free(rtransport);
2563 
2564 	return 0;
2565 }
2566 
2567 static int
2568 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2569 			  struct spdk_nvme_transport_id *trid,
2570 			  bool peer);
2571 
2572 static int
2573 nvmf_rdma_listen(struct spdk_nvmf_transport *transport,
2574 		 const struct spdk_nvme_transport_id *trid)
2575 {
2576 	struct spdk_nvmf_rdma_transport	*rtransport;
2577 	struct spdk_nvmf_rdma_device	*device;
2578 	struct spdk_nvmf_rdma_port	*port;
2579 	struct addrinfo			*res;
2580 	struct addrinfo			hints;
2581 	int				family;
2582 	int				rc;
2583 
2584 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2585 	assert(rtransport->event_channel != NULL);
2586 
2587 	pthread_mutex_lock(&rtransport->lock);
2588 	port = calloc(1, sizeof(*port));
2589 	if (!port) {
2590 		SPDK_ERRLOG("Port allocation failed\n");
2591 		pthread_mutex_unlock(&rtransport->lock);
2592 		return -ENOMEM;
2593 	}
2594 
2595 	port->trid = trid;
2596 
2597 	switch (trid->adrfam) {
2598 	case SPDK_NVMF_ADRFAM_IPV4:
2599 		family = AF_INET;
2600 		break;
2601 	case SPDK_NVMF_ADRFAM_IPV6:
2602 		family = AF_INET6;
2603 		break;
2604 	default:
2605 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", trid->adrfam);
2606 		free(port);
2607 		pthread_mutex_unlock(&rtransport->lock);
2608 		return -EINVAL;
2609 	}
2610 
2611 	memset(&hints, 0, sizeof(hints));
2612 	hints.ai_family = family;
2613 	hints.ai_flags = AI_NUMERICSERV;
2614 	hints.ai_socktype = SOCK_STREAM;
2615 	hints.ai_protocol = 0;
2616 
2617 	rc = getaddrinfo(trid->traddr, trid->trsvcid, &hints, &res);
2618 	if (rc) {
2619 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
2620 		free(port);
2621 		pthread_mutex_unlock(&rtransport->lock);
2622 		return -EINVAL;
2623 	}
2624 
2625 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
2626 	if (rc < 0) {
2627 		SPDK_ERRLOG("rdma_create_id() failed\n");
2628 		freeaddrinfo(res);
2629 		free(port);
2630 		pthread_mutex_unlock(&rtransport->lock);
2631 		return rc;
2632 	}
2633 
2634 	rc = rdma_bind_addr(port->id, res->ai_addr);
2635 	freeaddrinfo(res);
2636 
2637 	if (rc < 0) {
2638 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
2639 		rdma_destroy_id(port->id);
2640 		free(port);
2641 		pthread_mutex_unlock(&rtransport->lock);
2642 		return rc;
2643 	}
2644 
2645 	if (!port->id->verbs) {
2646 		SPDK_ERRLOG("ibv_context is null\n");
2647 		rdma_destroy_id(port->id);
2648 		free(port);
2649 		pthread_mutex_unlock(&rtransport->lock);
2650 		return -1;
2651 	}
2652 
2653 	rc = rdma_listen(port->id, transport->opts.acceptor_backlog);
2654 	if (rc < 0) {
2655 		SPDK_ERRLOG("rdma_listen() failed\n");
2656 		rdma_destroy_id(port->id);
2657 		free(port);
2658 		pthread_mutex_unlock(&rtransport->lock);
2659 		return rc;
2660 	}
2661 
2662 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2663 		if (device->context == port->id->verbs) {
2664 			port->device = device;
2665 			break;
2666 		}
2667 	}
2668 	if (!port->device) {
2669 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
2670 			    port->id->verbs);
2671 		rdma_destroy_id(port->id);
2672 		free(port);
2673 		pthread_mutex_unlock(&rtransport->lock);
2674 		return -EINVAL;
2675 	}
2676 
2677 	SPDK_NOTICELOG("*** NVMe/RDMA Target Listening on %s port %s ***\n",
2678 		       trid->traddr, trid->trsvcid);
2679 
2680 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
2681 	pthread_mutex_unlock(&rtransport->lock);
2682 	return 0;
2683 }
2684 
2685 static void
2686 nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
2687 		      const struct spdk_nvme_transport_id *trid)
2688 {
2689 	struct spdk_nvmf_rdma_transport *rtransport;
2690 	struct spdk_nvmf_rdma_port *port, *tmp;
2691 
2692 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2693 
2694 	pthread_mutex_lock(&rtransport->lock);
2695 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
2696 		if (spdk_nvme_transport_id_compare(port->trid, trid) == 0) {
2697 			TAILQ_REMOVE(&rtransport->ports, port, link);
2698 			rdma_destroy_id(port->id);
2699 			free(port);
2700 			break;
2701 		}
2702 	}
2703 
2704 	pthread_mutex_unlock(&rtransport->lock);
2705 }
2706 
2707 static void
2708 nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
2709 				struct spdk_nvmf_rdma_qpair *rqpair, bool drain)
2710 {
2711 	struct spdk_nvmf_request *req, *tmp;
2712 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
2713 	struct spdk_nvmf_rdma_resources *resources;
2714 
2715 	/* We process I/O in the data transfer pending queue at the highest priority. RDMA reads first */
2716 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_read_queue, state_link, req_tmp) {
2717 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2718 			break;
2719 		}
2720 	}
2721 
2722 	/* Then RDMA writes since reads have stronger restrictions than writes */
2723 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_write_queue, state_link, req_tmp) {
2724 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2725 			break;
2726 		}
2727 	}
2728 
2729 	/* The second highest priority is I/O waiting on memory buffers. */
2730 	STAILQ_FOREACH_SAFE(req, &rqpair->poller->group->group.pending_buf_queue, buf_link, tmp) {
2731 		rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
2732 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2733 			break;
2734 		}
2735 	}
2736 
2737 	resources = rqpair->resources;
2738 	while (!STAILQ_EMPTY(&resources->free_queue) && !STAILQ_EMPTY(&resources->incoming_queue)) {
2739 		rdma_req = STAILQ_FIRST(&resources->free_queue);
2740 		STAILQ_REMOVE_HEAD(&resources->free_queue, state_link);
2741 		rdma_req->recv = STAILQ_FIRST(&resources->incoming_queue);
2742 		STAILQ_REMOVE_HEAD(&resources->incoming_queue, link);
2743 
2744 		if (rqpair->srq != NULL) {
2745 			rdma_req->req.qpair = &rdma_req->recv->qpair->qpair;
2746 			rdma_req->recv->qpair->qd++;
2747 		} else {
2748 			rqpair->qd++;
2749 		}
2750 
2751 		rdma_req->receive_tsc = rdma_req->recv->receive_tsc;
2752 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
2753 		if (nvmf_rdma_request_process(rtransport, rdma_req) == false) {
2754 			break;
2755 		}
2756 	}
2757 	if (!STAILQ_EMPTY(&resources->incoming_queue) && STAILQ_EMPTY(&resources->free_queue)) {
2758 		rqpair->poller->stat.pending_free_request++;
2759 	}
2760 }
2761 
2762 static void
2763 _nvmf_rdma_qpair_disconnect(void *ctx)
2764 {
2765 	struct spdk_nvmf_qpair *qpair = ctx;
2766 
2767 	spdk_nvmf_qpair_disconnect(qpair, NULL, NULL);
2768 }
2769 
2770 static void
2771 _nvmf_rdma_try_disconnect(void *ctx)
2772 {
2773 	struct spdk_nvmf_qpair *qpair = ctx;
2774 	struct spdk_nvmf_poll_group *group;
2775 
2776 	/* Read the group out of the qpair. This is normally set and accessed only from
2777 	 * the thread that created the group. Here, we're not on that thread necessarily.
2778 	 * The data member qpair->group begins it's life as NULL and then is assigned to
2779 	 * a pointer and never changes. So fortunately reading this and checking for
2780 	 * non-NULL is thread safe in the x86_64 memory model. */
2781 	group = qpair->group;
2782 
2783 	if (group == NULL) {
2784 		/* The qpair hasn't been assigned to a group yet, so we can't
2785 		 * process a disconnect. Send a message to ourself and try again. */
2786 		spdk_thread_send_msg(spdk_get_thread(), _nvmf_rdma_try_disconnect, qpair);
2787 		return;
2788 	}
2789 
2790 	spdk_thread_send_msg(group->thread, _nvmf_rdma_qpair_disconnect, qpair);
2791 }
2792 
2793 static inline void
2794 nvmf_rdma_start_disconnect(struct spdk_nvmf_rdma_qpair *rqpair)
2795 {
2796 	if (!__atomic_test_and_set(&rqpair->disconnect_started, __ATOMIC_RELAXED)) {
2797 		_nvmf_rdma_try_disconnect(&rqpair->qpair);
2798 	}
2799 }
2800 
2801 static void nvmf_rdma_destroy_drained_qpair(void *ctx)
2802 {
2803 	struct spdk_nvmf_rdma_qpair *rqpair = ctx;
2804 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
2805 			struct spdk_nvmf_rdma_transport, transport);
2806 
2807 	/* In non SRQ path, we will reach rqpair->max_queue_depth. In SRQ path, we will get the last_wqe event. */
2808 	if (rqpair->current_send_depth != 0) {
2809 		return;
2810 	}
2811 
2812 	if (rqpair->srq == NULL && rqpair->current_recv_depth != rqpair->max_queue_depth) {
2813 		return;
2814 	}
2815 
2816 	if (rqpair->srq != NULL && rqpair->last_wqe_reached == false) {
2817 		return;
2818 	}
2819 
2820 	nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
2821 
2822 	/* Qpair will be destroyed after nvmf layer closes this qpair */
2823 	if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ERROR) {
2824 		return;
2825 	}
2826 
2827 	nvmf_rdma_qpair_destroy(rqpair);
2828 }
2829 
2830 
2831 static int
2832 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
2833 {
2834 	struct spdk_nvmf_qpair		*qpair;
2835 	struct spdk_nvmf_rdma_qpair	*rqpair;
2836 
2837 	if (evt->id == NULL) {
2838 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
2839 		return -1;
2840 	}
2841 
2842 	qpair = evt->id->context;
2843 	if (qpair == NULL) {
2844 		SPDK_ERRLOG("disconnect request: no active connection\n");
2845 		return -1;
2846 	}
2847 
2848 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2849 
2850 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair->cm_id, 0);
2851 
2852 	nvmf_rdma_start_disconnect(rqpair);
2853 
2854 	return 0;
2855 }
2856 
2857 #ifdef DEBUG
2858 static const char *CM_EVENT_STR[] = {
2859 	"RDMA_CM_EVENT_ADDR_RESOLVED",
2860 	"RDMA_CM_EVENT_ADDR_ERROR",
2861 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
2862 	"RDMA_CM_EVENT_ROUTE_ERROR",
2863 	"RDMA_CM_EVENT_CONNECT_REQUEST",
2864 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
2865 	"RDMA_CM_EVENT_CONNECT_ERROR",
2866 	"RDMA_CM_EVENT_UNREACHABLE",
2867 	"RDMA_CM_EVENT_REJECTED",
2868 	"RDMA_CM_EVENT_ESTABLISHED",
2869 	"RDMA_CM_EVENT_DISCONNECTED",
2870 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
2871 	"RDMA_CM_EVENT_MULTICAST_JOIN",
2872 	"RDMA_CM_EVENT_MULTICAST_ERROR",
2873 	"RDMA_CM_EVENT_ADDR_CHANGE",
2874 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
2875 };
2876 #endif /* DEBUG */
2877 
2878 static void
2879 nvmf_rdma_disconnect_qpairs_on_port(struct spdk_nvmf_rdma_transport *rtransport,
2880 				    struct spdk_nvmf_rdma_port *port)
2881 {
2882 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2883 	struct spdk_nvmf_rdma_poller		*rpoller;
2884 	struct spdk_nvmf_rdma_qpair		*rqpair;
2885 
2886 	TAILQ_FOREACH(rgroup, &rtransport->poll_groups, link) {
2887 		TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
2888 			TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
2889 				if (rqpair->listen_id == port->id) {
2890 					nvmf_rdma_start_disconnect(rqpair);
2891 				}
2892 			}
2893 		}
2894 	}
2895 }
2896 
2897 static bool
2898 nvmf_rdma_handle_cm_event_addr_change(struct spdk_nvmf_transport *transport,
2899 				      struct rdma_cm_event *event)
2900 {
2901 	const struct spdk_nvme_transport_id	*trid;
2902 	struct spdk_nvmf_rdma_port		*port;
2903 	struct spdk_nvmf_rdma_transport		*rtransport;
2904 	bool					event_acked = false;
2905 
2906 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2907 	TAILQ_FOREACH(port, &rtransport->ports, link) {
2908 		if (port->id == event->id) {
2909 			SPDK_ERRLOG("ADDR_CHANGE: IP %s:%s migrated\n", port->trid->traddr, port->trid->trsvcid);
2910 			rdma_ack_cm_event(event);
2911 			event_acked = true;
2912 			trid = port->trid;
2913 			break;
2914 		}
2915 	}
2916 
2917 	if (event_acked) {
2918 		nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
2919 
2920 		nvmf_rdma_stop_listen(transport, trid);
2921 		nvmf_rdma_listen(transport, trid);
2922 	}
2923 
2924 	return event_acked;
2925 }
2926 
2927 static void
2928 nvmf_rdma_handle_cm_event_port_removal(struct spdk_nvmf_transport *transport,
2929 				       struct rdma_cm_event *event)
2930 {
2931 	struct spdk_nvmf_rdma_port		*port;
2932 	struct spdk_nvmf_rdma_transport		*rtransport;
2933 
2934 	port = event->id->context;
2935 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2936 
2937 	SPDK_NOTICELOG("Port %s:%s is being removed\n", port->trid->traddr, port->trid->trsvcid);
2938 
2939 	nvmf_rdma_disconnect_qpairs_on_port(rtransport, port);
2940 
2941 	rdma_ack_cm_event(event);
2942 
2943 	while (spdk_nvmf_transport_stop_listen(transport, port->trid) == 0) {
2944 		;
2945 	}
2946 }
2947 
2948 static void
2949 nvmf_process_cm_event(struct spdk_nvmf_transport *transport)
2950 {
2951 	struct spdk_nvmf_rdma_transport *rtransport;
2952 	struct rdma_cm_event		*event;
2953 	int				rc;
2954 	bool				event_acked;
2955 
2956 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2957 
2958 	if (rtransport->event_channel == NULL) {
2959 		return;
2960 	}
2961 
2962 	while (1) {
2963 		event_acked = false;
2964 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
2965 		if (rc) {
2966 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
2967 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
2968 			}
2969 			break;
2970 		}
2971 
2972 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
2973 
2974 		spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
2975 
2976 		switch (event->event) {
2977 		case RDMA_CM_EVENT_ADDR_RESOLVED:
2978 		case RDMA_CM_EVENT_ADDR_ERROR:
2979 		case RDMA_CM_EVENT_ROUTE_RESOLVED:
2980 		case RDMA_CM_EVENT_ROUTE_ERROR:
2981 			/* No action required. The target never attempts to resolve routes. */
2982 			break;
2983 		case RDMA_CM_EVENT_CONNECT_REQUEST:
2984 			rc = nvmf_rdma_connect(transport, event);
2985 			if (rc < 0) {
2986 				SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
2987 				break;
2988 			}
2989 			break;
2990 		case RDMA_CM_EVENT_CONNECT_RESPONSE:
2991 			/* The target never initiates a new connection. So this will not occur. */
2992 			break;
2993 		case RDMA_CM_EVENT_CONNECT_ERROR:
2994 			/* Can this happen? The docs say it can, but not sure what causes it. */
2995 			break;
2996 		case RDMA_CM_EVENT_UNREACHABLE:
2997 		case RDMA_CM_EVENT_REJECTED:
2998 			/* These only occur on the client side. */
2999 			break;
3000 		case RDMA_CM_EVENT_ESTABLISHED:
3001 			/* TODO: Should we be waiting for this event anywhere? */
3002 			break;
3003 		case RDMA_CM_EVENT_DISCONNECTED:
3004 			rc = nvmf_rdma_disconnect(event);
3005 			if (rc < 0) {
3006 				SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
3007 				break;
3008 			}
3009 			break;
3010 		case RDMA_CM_EVENT_DEVICE_REMOVAL:
3011 			/* In case of device removal, kernel IB part triggers IBV_EVENT_DEVICE_FATAL
3012 			 * which triggers RDMA_CM_EVENT_DEVICE_REMOVAL on all cma_id’s.
3013 			 * Once these events are sent to SPDK, we should release all IB resources and
3014 			 * don't make attempts to call any ibv_query/modify/create functions. We can only call
3015 			 * ibv_destory* functions to release user space memory allocated by IB. All kernel
3016 			 * resources are already cleaned. */
3017 			if (event->id->qp) {
3018 				/* If rdma_cm event has a valid `qp` pointer then the event refers to the
3019 				 * corresponding qpair. Otherwise the event refers to a listening device */
3020 				rc = nvmf_rdma_disconnect(event);
3021 				if (rc < 0) {
3022 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
3023 					break;
3024 				}
3025 			} else {
3026 				nvmf_rdma_handle_cm_event_port_removal(transport, event);
3027 				event_acked = true;
3028 			}
3029 			break;
3030 		case RDMA_CM_EVENT_MULTICAST_JOIN:
3031 		case RDMA_CM_EVENT_MULTICAST_ERROR:
3032 			/* Multicast is not used */
3033 			break;
3034 		case RDMA_CM_EVENT_ADDR_CHANGE:
3035 			event_acked = nvmf_rdma_handle_cm_event_addr_change(transport, event);
3036 			break;
3037 		case RDMA_CM_EVENT_TIMEWAIT_EXIT:
3038 			/* For now, do nothing. The target never re-uses queue pairs. */
3039 			break;
3040 		default:
3041 			SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
3042 			break;
3043 		}
3044 		if (!event_acked) {
3045 			rdma_ack_cm_event(event);
3046 		}
3047 	}
3048 }
3049 
3050 static void
3051 nvmf_rdma_handle_qp_fatal(struct spdk_nvmf_rdma_qpair *rqpair)
3052 {
3053 	nvmf_rdma_update_ibv_state(rqpair);
3054 	nvmf_rdma_start_disconnect(rqpair);
3055 }
3056 
3057 static void
3058 nvmf_rdma_handle_last_wqe_reached(struct spdk_nvmf_rdma_qpair *rqpair)
3059 {
3060 	rqpair->last_wqe_reached = true;
3061 	nvmf_rdma_destroy_drained_qpair(rqpair);
3062 }
3063 
3064 static void
3065 nvmf_rdma_handle_sq_drained(struct spdk_nvmf_rdma_qpair *rqpair)
3066 {
3067 	nvmf_rdma_start_disconnect(rqpair);
3068 }
3069 
3070 static void
3071 nvmf_rdma_qpair_process_ibv_event(void *ctx)
3072 {
3073 	struct spdk_nvmf_rdma_ibv_event_ctx *event_ctx = ctx;
3074 
3075 	if (event_ctx->rqpair) {
3076 		STAILQ_REMOVE(&event_ctx->rqpair->ibv_events, event_ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3077 		if (event_ctx->cb_fn) {
3078 			event_ctx->cb_fn(event_ctx->rqpair);
3079 		}
3080 	}
3081 	free(event_ctx);
3082 }
3083 
3084 static int
3085 nvmf_rdma_send_qpair_async_event(struct spdk_nvmf_rdma_qpair *rqpair,
3086 				 spdk_nvmf_rdma_qpair_ibv_event fn)
3087 {
3088 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx;
3089 	struct spdk_thread *thr = NULL;
3090 	int rc;
3091 
3092 	if (rqpair->qpair.group) {
3093 		thr = rqpair->qpair.group->thread;
3094 	} else if (rqpair->destruct_channel) {
3095 		thr = spdk_io_channel_get_thread(rqpair->destruct_channel);
3096 	}
3097 
3098 	if (!thr) {
3099 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "rqpair %p has no thread\n", rqpair);
3100 		return -EINVAL;
3101 	}
3102 
3103 	ctx = calloc(1, sizeof(*ctx));
3104 	if (!ctx) {
3105 		return -ENOMEM;
3106 	}
3107 
3108 	ctx->rqpair = rqpair;
3109 	ctx->cb_fn = fn;
3110 	STAILQ_INSERT_TAIL(&rqpair->ibv_events, ctx, link);
3111 
3112 	rc = spdk_thread_send_msg(thr, nvmf_rdma_qpair_process_ibv_event, ctx);
3113 	if (rc) {
3114 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3115 		free(ctx);
3116 	}
3117 
3118 	return rc;
3119 }
3120 
3121 static void
3122 nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
3123 {
3124 	int				rc;
3125 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
3126 	struct ibv_async_event		event;
3127 
3128 	rc = ibv_get_async_event(device->context, &event);
3129 
3130 	if (rc) {
3131 		SPDK_ERRLOG("Failed to get async_event (%d): %s\n",
3132 			    errno, spdk_strerror(errno));
3133 		return;
3134 	}
3135 
3136 	switch (event.event_type) {
3137 	case IBV_EVENT_QP_FATAL:
3138 		rqpair = event.element.qp->qp_context;
3139 		SPDK_ERRLOG("Fatal event received for rqpair %p\n", rqpair);
3140 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3141 				  (uintptr_t)rqpair->cm_id, event.event_type);
3142 		rc = nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_qp_fatal);
3143 		if (rc) {
3144 			SPDK_WARNLOG("Failed to send QP_FATAL event. rqpair %p, err %d\n", rqpair, rc);
3145 			nvmf_rdma_handle_qp_fatal(rqpair);
3146 		}
3147 		break;
3148 	case IBV_EVENT_QP_LAST_WQE_REACHED:
3149 		/* This event only occurs for shared receive queues. */
3150 		rqpair = event.element.qp->qp_context;
3151 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Last WQE reached event received for rqpair %p\n", rqpair);
3152 		rc = nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_last_wqe_reached);
3153 		if (rc) {
3154 			SPDK_WARNLOG("Failed to send LAST_WQE_REACHED event. rqpair %p, err %d\n", rqpair, rc);
3155 			rqpair->last_wqe_reached = true;
3156 		}
3157 		break;
3158 	case IBV_EVENT_SQ_DRAINED:
3159 		/* This event occurs frequently in both error and non-error states.
3160 		 * Check if the qpair is in an error state before sending a message. */
3161 		rqpair = event.element.qp->qp_context;
3162 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Last sq drained event received for rqpair %p\n", rqpair);
3163 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3164 				  (uintptr_t)rqpair->cm_id, event.event_type);
3165 		if (nvmf_rdma_update_ibv_state(rqpair) == IBV_QPS_ERR) {
3166 			rc = nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_sq_drained);
3167 			if (rc) {
3168 				SPDK_WARNLOG("Failed to send SQ_DRAINED event. rqpair %p, err %d\n", rqpair, rc);
3169 				nvmf_rdma_handle_sq_drained(rqpair);
3170 			}
3171 		}
3172 		break;
3173 	case IBV_EVENT_QP_REQ_ERR:
3174 	case IBV_EVENT_QP_ACCESS_ERR:
3175 	case IBV_EVENT_COMM_EST:
3176 	case IBV_EVENT_PATH_MIG:
3177 	case IBV_EVENT_PATH_MIG_ERR:
3178 		SPDK_NOTICELOG("Async event: %s\n",
3179 			       ibv_event_type_str(event.event_type));
3180 		rqpair = event.element.qp->qp_context;
3181 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3182 				  (uintptr_t)rqpair->cm_id, event.event_type);
3183 		nvmf_rdma_update_ibv_state(rqpair);
3184 		break;
3185 	case IBV_EVENT_CQ_ERR:
3186 	case IBV_EVENT_DEVICE_FATAL:
3187 	case IBV_EVENT_PORT_ACTIVE:
3188 	case IBV_EVENT_PORT_ERR:
3189 	case IBV_EVENT_LID_CHANGE:
3190 	case IBV_EVENT_PKEY_CHANGE:
3191 	case IBV_EVENT_SM_CHANGE:
3192 	case IBV_EVENT_SRQ_ERR:
3193 	case IBV_EVENT_SRQ_LIMIT_REACHED:
3194 	case IBV_EVENT_CLIENT_REREGISTER:
3195 	case IBV_EVENT_GID_CHANGE:
3196 	default:
3197 		SPDK_NOTICELOG("Async event: %s\n",
3198 			       ibv_event_type_str(event.event_type));
3199 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
3200 		break;
3201 	}
3202 	ibv_ack_async_event(&event);
3203 }
3204 
3205 static uint32_t
3206 nvmf_rdma_accept(struct spdk_nvmf_transport *transport)
3207 {
3208 	int	nfds, i = 0;
3209 	struct spdk_nvmf_rdma_transport *rtransport;
3210 	struct spdk_nvmf_rdma_device *device, *tmp;
3211 	uint32_t count;
3212 
3213 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3214 	count = nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
3215 
3216 	if (nfds <= 0) {
3217 		return 0;
3218 	}
3219 
3220 	/* The first poll descriptor is RDMA CM event */
3221 	if (rtransport->poll_fds[i++].revents & POLLIN) {
3222 		nvmf_process_cm_event(transport);
3223 		nfds--;
3224 	}
3225 
3226 	if (nfds == 0) {
3227 		return count;
3228 	}
3229 
3230 	/* Second and subsequent poll descriptors are IB async events */
3231 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
3232 		if (rtransport->poll_fds[i++].revents & POLLIN) {
3233 			nvmf_process_ib_event(device);
3234 			nfds--;
3235 		}
3236 	}
3237 	/* check all flagged fd's have been served */
3238 	assert(nfds == 0);
3239 
3240 	return count;
3241 }
3242 
3243 static void
3244 nvmf_rdma_cdata_init(struct spdk_nvmf_transport *transport, struct spdk_nvmf_subsystem *subsystem,
3245 		     struct spdk_nvmf_ctrlr_data *cdata)
3246 {
3247 	cdata->nvmf_specific.msdbd = SPDK_NVMF_MAX_SGL_ENTRIES;
3248 
3249 	/* Disable in-capsule data transfer for RDMA controller when dif_insert_or_strip is enabled
3250 	since in-capsule data only works with NVME drives that support SGL memory layout */
3251 	if (transport->opts.dif_insert_or_strip) {
3252 		cdata->nvmf_specific.ioccsz = sizeof(struct spdk_nvme_cmd) / 16;
3253 	}
3254 }
3255 
3256 static void
3257 nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
3258 		   struct spdk_nvme_transport_id *trid,
3259 		   struct spdk_nvmf_discovery_log_page_entry *entry)
3260 {
3261 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
3262 	entry->adrfam = trid->adrfam;
3263 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
3264 
3265 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
3266 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
3267 
3268 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
3269 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
3270 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
3271 }
3272 
3273 static void
3274 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
3275 
3276 static struct spdk_nvmf_transport_poll_group *
3277 nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
3278 {
3279 	struct spdk_nvmf_rdma_transport		*rtransport;
3280 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3281 	struct spdk_nvmf_rdma_poller		*poller;
3282 	struct spdk_nvmf_rdma_device		*device;
3283 	struct ibv_srq_init_attr		srq_init_attr;
3284 	struct spdk_nvmf_rdma_resource_opts	opts;
3285 	int					num_cqe;
3286 
3287 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3288 
3289 	rgroup = calloc(1, sizeof(*rgroup));
3290 	if (!rgroup) {
3291 		return NULL;
3292 	}
3293 
3294 	TAILQ_INIT(&rgroup->pollers);
3295 	STAILQ_INIT(&rgroup->retired_bufs);
3296 
3297 	pthread_mutex_lock(&rtransport->lock);
3298 	TAILQ_FOREACH(device, &rtransport->devices, link) {
3299 		poller = calloc(1, sizeof(*poller));
3300 		if (!poller) {
3301 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
3302 			nvmf_rdma_poll_group_destroy(&rgroup->group);
3303 			pthread_mutex_unlock(&rtransport->lock);
3304 			return NULL;
3305 		}
3306 
3307 		poller->device = device;
3308 		poller->group = rgroup;
3309 
3310 		TAILQ_INIT(&poller->qpairs);
3311 		STAILQ_INIT(&poller->qpairs_pending_send);
3312 		STAILQ_INIT(&poller->qpairs_pending_recv);
3313 
3314 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
3315 		if (transport->opts.no_srq == false && device->num_srq < device->attr.max_srq) {
3316 			poller->max_srq_depth = transport->opts.max_srq_depth;
3317 
3318 			device->num_srq++;
3319 			memset(&srq_init_attr, 0, sizeof(struct ibv_srq_init_attr));
3320 			srq_init_attr.attr.max_wr = poller->max_srq_depth;
3321 			srq_init_attr.attr.max_sge = spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
3322 			poller->srq = ibv_create_srq(device->pd, &srq_init_attr);
3323 			if (!poller->srq) {
3324 				SPDK_ERRLOG("Unable to create shared receive queue, errno %d\n", errno);
3325 				nvmf_rdma_poll_group_destroy(&rgroup->group);
3326 				pthread_mutex_unlock(&rtransport->lock);
3327 				return NULL;
3328 			}
3329 
3330 			opts.qp = poller->srq;
3331 			opts.pd = device->pd;
3332 			opts.qpair = NULL;
3333 			opts.shared = true;
3334 			opts.max_queue_depth = poller->max_srq_depth;
3335 			opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
3336 
3337 			poller->resources = nvmf_rdma_resources_create(&opts);
3338 			if (!poller->resources) {
3339 				SPDK_ERRLOG("Unable to allocate resources for shared receive queue.\n");
3340 				nvmf_rdma_poll_group_destroy(&rgroup->group);
3341 				pthread_mutex_unlock(&rtransport->lock);
3342 				return NULL;
3343 			}
3344 		}
3345 
3346 		/*
3347 		 * When using an srq, we can limit the completion queue at startup.
3348 		 * The following formula represents the calculation:
3349 		 * num_cqe = num_recv + num_data_wr + num_send_wr.
3350 		 * where num_recv=num_data_wr=and num_send_wr=poller->max_srq_depth
3351 		 */
3352 		if (poller->srq) {
3353 			num_cqe = poller->max_srq_depth * 3;
3354 		} else {
3355 			num_cqe = DEFAULT_NVMF_RDMA_CQ_SIZE;
3356 		}
3357 
3358 		poller->cq = ibv_create_cq(device->context, num_cqe, poller, NULL, 0);
3359 		if (!poller->cq) {
3360 			SPDK_ERRLOG("Unable to create completion queue\n");
3361 			nvmf_rdma_poll_group_destroy(&rgroup->group);
3362 			pthread_mutex_unlock(&rtransport->lock);
3363 			return NULL;
3364 		}
3365 		poller->num_cqe = num_cqe;
3366 	}
3367 
3368 	TAILQ_INSERT_TAIL(&rtransport->poll_groups, rgroup, link);
3369 	if (rtransport->conn_sched.next_admin_pg == NULL) {
3370 		rtransport->conn_sched.next_admin_pg = rgroup;
3371 		rtransport->conn_sched.next_io_pg = rgroup;
3372 	}
3373 
3374 	pthread_mutex_unlock(&rtransport->lock);
3375 	return &rgroup->group;
3376 }
3377 
3378 static struct spdk_nvmf_transport_poll_group *
3379 nvmf_rdma_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
3380 {
3381 	struct spdk_nvmf_rdma_transport *rtransport;
3382 	struct spdk_nvmf_rdma_poll_group **pg;
3383 	struct spdk_nvmf_transport_poll_group *result;
3384 
3385 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
3386 
3387 	pthread_mutex_lock(&rtransport->lock);
3388 
3389 	if (TAILQ_EMPTY(&rtransport->poll_groups)) {
3390 		pthread_mutex_unlock(&rtransport->lock);
3391 		return NULL;
3392 	}
3393 
3394 	if (qpair->qid == 0) {
3395 		pg = &rtransport->conn_sched.next_admin_pg;
3396 	} else {
3397 		pg = &rtransport->conn_sched.next_io_pg;
3398 	}
3399 
3400 	assert(*pg != NULL);
3401 
3402 	result = &(*pg)->group;
3403 
3404 	*pg = TAILQ_NEXT(*pg, link);
3405 	if (*pg == NULL) {
3406 		*pg = TAILQ_FIRST(&rtransport->poll_groups);
3407 	}
3408 
3409 	pthread_mutex_unlock(&rtransport->lock);
3410 
3411 	return result;
3412 }
3413 
3414 static void
3415 nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
3416 {
3417 	struct spdk_nvmf_rdma_poll_group	*rgroup, *next_rgroup;
3418 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
3419 	struct spdk_nvmf_rdma_qpair		*qpair, *tmp_qpair;
3420 	struct spdk_nvmf_transport_pg_cache_buf	*buf, *tmp_buf;
3421 	struct spdk_nvmf_rdma_transport		*rtransport;
3422 
3423 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3424 	if (!rgroup) {
3425 		return;
3426 	}
3427 
3428 	/* free all retired buffers back to the transport so we don't short the mempool. */
3429 	STAILQ_FOREACH_SAFE(buf, &rgroup->retired_bufs, link, tmp_buf) {
3430 		STAILQ_REMOVE(&rgroup->retired_bufs, buf, spdk_nvmf_transport_pg_cache_buf, link);
3431 		assert(group->transport != NULL);
3432 		spdk_mempool_put(group->transport->data_buf_pool, buf);
3433 	}
3434 
3435 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
3436 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
3437 
3438 		TAILQ_FOREACH_SAFE(qpair, &poller->qpairs, link, tmp_qpair) {
3439 			nvmf_rdma_qpair_destroy(qpair);
3440 		}
3441 
3442 		if (poller->srq) {
3443 			if (poller->resources) {
3444 				nvmf_rdma_resources_destroy(poller->resources);
3445 			}
3446 			ibv_destroy_srq(poller->srq);
3447 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Destroyed RDMA shared queue %p\n", poller->srq);
3448 		}
3449 
3450 		if (poller->cq) {
3451 			ibv_destroy_cq(poller->cq);
3452 		}
3453 
3454 		free(poller);
3455 	}
3456 
3457 	if (rgroup->group.transport == NULL) {
3458 		/* Transport can be NULL when nvmf_rdma_poll_group_create()
3459 		 * calls this function directly in a failure path. */
3460 		free(rgroup);
3461 		return;
3462 	}
3463 
3464 	rtransport = SPDK_CONTAINEROF(rgroup->group.transport, struct spdk_nvmf_rdma_transport, transport);
3465 
3466 	pthread_mutex_lock(&rtransport->lock);
3467 	next_rgroup = TAILQ_NEXT(rgroup, link);
3468 	TAILQ_REMOVE(&rtransport->poll_groups, rgroup, link);
3469 	if (next_rgroup == NULL) {
3470 		next_rgroup = TAILQ_FIRST(&rtransport->poll_groups);
3471 	}
3472 	if (rtransport->conn_sched.next_admin_pg == rgroup) {
3473 		rtransport->conn_sched.next_admin_pg = next_rgroup;
3474 	}
3475 	if (rtransport->conn_sched.next_io_pg == rgroup) {
3476 		rtransport->conn_sched.next_io_pg = next_rgroup;
3477 	}
3478 	pthread_mutex_unlock(&rtransport->lock);
3479 
3480 	free(rgroup);
3481 }
3482 
3483 static void
3484 nvmf_rdma_qpair_reject_connection(struct spdk_nvmf_rdma_qpair *rqpair)
3485 {
3486 	if (rqpair->cm_id != NULL) {
3487 		nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
3488 	}
3489 	nvmf_rdma_qpair_destroy(rqpair);
3490 }
3491 
3492 static int
3493 nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
3494 			 struct spdk_nvmf_qpair *qpair)
3495 {
3496 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3497 	struct spdk_nvmf_rdma_qpair		*rqpair;
3498 	struct spdk_nvmf_rdma_device		*device;
3499 	struct spdk_nvmf_rdma_poller		*poller;
3500 	int					rc;
3501 
3502 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3503 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3504 
3505 	device = rqpair->device;
3506 
3507 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
3508 		if (poller->device == device) {
3509 			break;
3510 		}
3511 	}
3512 
3513 	if (!poller) {
3514 		SPDK_ERRLOG("No poller found for device.\n");
3515 		return -1;
3516 	}
3517 
3518 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
3519 	rqpair->poller = poller;
3520 	rqpair->srq = rqpair->poller->srq;
3521 
3522 	rc = nvmf_rdma_qpair_initialize(qpair);
3523 	if (rc < 0) {
3524 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
3525 		return -1;
3526 	}
3527 
3528 	rc = nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
3529 	if (rc) {
3530 		/* Try to reject, but we probably can't */
3531 		nvmf_rdma_qpair_reject_connection(rqpair);
3532 		return -1;
3533 	}
3534 
3535 	nvmf_rdma_update_ibv_state(rqpair);
3536 
3537 	return 0;
3538 }
3539 
3540 static int
3541 nvmf_rdma_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
3542 			    struct spdk_nvmf_qpair *qpair)
3543 {
3544 	struct spdk_nvmf_rdma_qpair		*rqpair;
3545 
3546 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3547 	assert(group->transport->tgt != NULL);
3548 
3549 	rqpair->destruct_channel = spdk_get_io_channel(group->transport->tgt);
3550 
3551 	if (!rqpair->destruct_channel) {
3552 		SPDK_WARNLOG("failed to get io_channel, qpair %p\n", qpair);
3553 		return 0;
3554 	}
3555 
3556 	/* Sanity check that we get io_channel on the correct thread */
3557 	if (qpair->group) {
3558 		assert(qpair->group->thread == spdk_io_channel_get_thread(rqpair->destruct_channel));
3559 	}
3560 
3561 	return 0;
3562 }
3563 
3564 static int
3565 nvmf_rdma_request_free(struct spdk_nvmf_request *req)
3566 {
3567 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
3568 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3569 			struct spdk_nvmf_rdma_transport, transport);
3570 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3571 					      struct spdk_nvmf_rdma_qpair, qpair);
3572 
3573 	/*
3574 	 * AER requests are freed when a qpair is destroyed. The recv corresponding to that request
3575 	 * needs to be returned to the shared receive queue or the poll group will eventually be
3576 	 * starved of RECV structures.
3577 	 */
3578 	if (rqpair->srq && rdma_req->recv) {
3579 		int rc;
3580 		struct ibv_recv_wr *bad_recv_wr;
3581 
3582 		rc = ibv_post_srq_recv(rqpair->srq, &rdma_req->recv->wr, &bad_recv_wr);
3583 		if (rc) {
3584 			SPDK_ERRLOG("Unable to re-post rx descriptor\n");
3585 		}
3586 	}
3587 
3588 	_nvmf_rdma_request_free(rdma_req, rtransport);
3589 	return 0;
3590 }
3591 
3592 static int
3593 nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
3594 {
3595 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3596 			struct spdk_nvmf_rdma_transport, transport);
3597 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
3598 			struct spdk_nvmf_rdma_request, req);
3599 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3600 			struct spdk_nvmf_rdma_qpair, qpair);
3601 
3602 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3603 		/* The connection is alive, so process the request as normal */
3604 		rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
3605 	} else {
3606 		/* The connection is dead. Move the request directly to the completed state. */
3607 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3608 	}
3609 
3610 	nvmf_rdma_request_process(rtransport, rdma_req);
3611 
3612 	return 0;
3613 }
3614 
3615 static int
3616 nvmf_rdma_destroy_defunct_qpair(void *ctx)
3617 {
3618 	struct spdk_nvmf_rdma_qpair	*rqpair = ctx;
3619 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
3620 			struct spdk_nvmf_rdma_transport, transport);
3621 
3622 	SPDK_INFOLOG(SPDK_LOG_RDMA, "QP#%d hasn't been drained as expected, manually destroy it\n",
3623 		     rqpair->qpair.qid);
3624 
3625 	nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
3626 	nvmf_rdma_qpair_destroy(rqpair);
3627 
3628 	return SPDK_POLLER_BUSY;
3629 }
3630 
3631 static void
3632 nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair)
3633 {
3634 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3635 
3636 	if (rqpair->disconnect_flags & RDMA_QP_DISCONNECTING) {
3637 		return;
3638 	}
3639 
3640 	rqpair->disconnect_flags |= RDMA_QP_DISCONNECTING;
3641 
3642 	/* This happens only when the qpair is disconnected before
3643 	 * it is added to the poll group. Since there is no poll group,
3644 	 * the RDMA qp has not been initialized yet and the RDMA CM
3645 	 * event has not yet been acknowledged, so we need to reject it.
3646 	 */
3647 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
3648 		nvmf_rdma_qpair_reject_connection(rqpair);
3649 		return;
3650 	}
3651 
3652 	if (rqpair->rdma_qp) {
3653 		spdk_rdma_qp_disconnect(rqpair->rdma_qp);
3654 	}
3655 
3656 	rqpair->destruct_poller = SPDK_POLLER_REGISTER(nvmf_rdma_destroy_defunct_qpair, (void *)rqpair,
3657 				  NVMF_RDMA_QPAIR_DESTROY_TIMEOUT_US);
3658 }
3659 
3660 static struct spdk_nvmf_rdma_qpair *
3661 get_rdma_qpair_from_wc(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_wc *wc)
3662 {
3663 	struct spdk_nvmf_rdma_qpair *rqpair;
3664 	/* @todo: improve QP search */
3665 	TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
3666 		if (wc->qp_num == rqpair->rdma_qp->qp->qp_num) {
3667 			return rqpair;
3668 		}
3669 	}
3670 	SPDK_ERRLOG("Didn't find QP with qp_num %u\n", wc->qp_num);
3671 	return NULL;
3672 }
3673 
3674 #ifdef DEBUG
3675 static int
3676 nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
3677 {
3678 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
3679 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
3680 }
3681 #endif
3682 
3683 static void
3684 _poller_reset_failed_recvs(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_recv_wr *bad_recv_wr,
3685 			   int rc)
3686 {
3687 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3688 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3689 
3690 	SPDK_ERRLOG("Failed to post a recv for the poller %p with errno %d\n", rpoller, -rc);
3691 	while (bad_recv_wr != NULL) {
3692 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_recv_wr->wr_id;
3693 		rdma_recv = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3694 
3695 		rdma_recv->qpair->current_recv_depth++;
3696 		bad_recv_wr = bad_recv_wr->next;
3697 		SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rdma_recv->qpair, -rc);
3698 		nvmf_rdma_start_disconnect(rdma_recv->qpair);
3699 	}
3700 }
3701 
3702 static void
3703 _qp_reset_failed_recvs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *bad_recv_wr, int rc)
3704 {
3705 	SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rqpair, -rc);
3706 	while (bad_recv_wr != NULL) {
3707 		bad_recv_wr = bad_recv_wr->next;
3708 		rqpair->current_recv_depth++;
3709 	}
3710 	nvmf_rdma_start_disconnect(rqpair);
3711 }
3712 
3713 static void
3714 _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
3715 		     struct spdk_nvmf_rdma_poller *rpoller)
3716 {
3717 	struct spdk_nvmf_rdma_qpair	*rqpair;
3718 	struct ibv_recv_wr		*bad_recv_wr;
3719 	int				rc;
3720 
3721 	if (rpoller->srq) {
3722 		if (rpoller->resources->recvs_to_post.first != NULL) {
3723 			rc = ibv_post_srq_recv(rpoller->srq, rpoller->resources->recvs_to_post.first, &bad_recv_wr);
3724 			if (rc) {
3725 				_poller_reset_failed_recvs(rpoller, bad_recv_wr, rc);
3726 			}
3727 			rpoller->resources->recvs_to_post.first = NULL;
3728 			rpoller->resources->recvs_to_post.last = NULL;
3729 		}
3730 	} else {
3731 		while (!STAILQ_EMPTY(&rpoller->qpairs_pending_recv)) {
3732 			rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_recv);
3733 			assert(rqpair->resources->recvs_to_post.first != NULL);
3734 			rc = ibv_post_recv(rqpair->rdma_qp->qp, rqpair->resources->recvs_to_post.first, &bad_recv_wr);
3735 			if (rc) {
3736 				_qp_reset_failed_recvs(rqpair, bad_recv_wr, rc);
3737 			}
3738 			rqpair->resources->recvs_to_post.first = NULL;
3739 			rqpair->resources->recvs_to_post.last = NULL;
3740 			STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_recv, recv_link);
3741 		}
3742 	}
3743 }
3744 
3745 static void
3746 _qp_reset_failed_sends(struct spdk_nvmf_rdma_transport *rtransport,
3747 		       struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_send_wr *bad_wr, int rc)
3748 {
3749 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3750 	struct spdk_nvmf_rdma_request	*prev_rdma_req = NULL, *cur_rdma_req = NULL;
3751 
3752 	SPDK_ERRLOG("Failed to post a send for the qpair %p with errno %d\n", rqpair, -rc);
3753 	for (; bad_wr != NULL; bad_wr = bad_wr->next) {
3754 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_wr->wr_id;
3755 		assert(rqpair->current_send_depth > 0);
3756 		rqpair->current_send_depth--;
3757 		switch (bad_rdma_wr->type) {
3758 		case RDMA_WR_TYPE_DATA:
3759 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3760 			if (bad_wr->opcode == IBV_WR_RDMA_READ) {
3761 				assert(rqpair->current_read_depth > 0);
3762 				rqpair->current_read_depth--;
3763 			}
3764 			break;
3765 		case RDMA_WR_TYPE_SEND:
3766 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3767 			break;
3768 		default:
3769 			SPDK_ERRLOG("Found a RECV in the list of pending SEND requests for qpair %p\n", rqpair);
3770 			prev_rdma_req = cur_rdma_req;
3771 			continue;
3772 		}
3773 
3774 		if (prev_rdma_req == cur_rdma_req) {
3775 			/* this request was handled by an earlier wr. i.e. we were performing an nvme read. */
3776 			/* We only have to check against prev_wr since each requests wrs are contiguous in this list. */
3777 			continue;
3778 		}
3779 
3780 		switch (cur_rdma_req->state) {
3781 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
3782 			cur_rdma_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
3783 			cur_rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
3784 			break;
3785 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
3786 		case RDMA_REQUEST_STATE_COMPLETING:
3787 			cur_rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3788 			break;
3789 		default:
3790 			SPDK_ERRLOG("Found a request in a bad state %d when draining pending SEND requests for qpair %p\n",
3791 				    cur_rdma_req->state, rqpair);
3792 			continue;
3793 		}
3794 
3795 		nvmf_rdma_request_process(rtransport, cur_rdma_req);
3796 		prev_rdma_req = cur_rdma_req;
3797 	}
3798 
3799 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3800 		/* Disconnect the connection. */
3801 		nvmf_rdma_start_disconnect(rqpair);
3802 	}
3803 
3804 }
3805 
3806 static void
3807 _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
3808 		     struct spdk_nvmf_rdma_poller *rpoller)
3809 {
3810 	struct spdk_nvmf_rdma_qpair	*rqpair;
3811 	struct ibv_send_wr		*bad_wr = NULL;
3812 	int				rc;
3813 
3814 	while (!STAILQ_EMPTY(&rpoller->qpairs_pending_send)) {
3815 		rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_send);
3816 		rc = spdk_rdma_qp_flush_send_wrs(rqpair->rdma_qp, &bad_wr);
3817 
3818 		/* bad wr always points to the first wr that failed. */
3819 		if (rc) {
3820 			_qp_reset_failed_sends(rtransport, rqpair, bad_wr, rc);
3821 		}
3822 		STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_send, send_link);
3823 	}
3824 }
3825 
3826 static int
3827 nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
3828 		      struct spdk_nvmf_rdma_poller *rpoller)
3829 {
3830 	struct ibv_wc wc[32];
3831 	struct spdk_nvmf_rdma_wr	*rdma_wr;
3832 	struct spdk_nvmf_rdma_request	*rdma_req;
3833 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3834 	struct spdk_nvmf_rdma_qpair	*rqpair;
3835 	int reaped, i;
3836 	int count = 0;
3837 	bool error = false;
3838 	uint64_t poll_tsc = spdk_get_ticks();
3839 
3840 	/* Poll for completing operations. */
3841 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
3842 	if (reaped < 0) {
3843 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
3844 			    errno, spdk_strerror(errno));
3845 		return -1;
3846 	}
3847 
3848 	rpoller->stat.polls++;
3849 	rpoller->stat.completions += reaped;
3850 
3851 	for (i = 0; i < reaped; i++) {
3852 
3853 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
3854 
3855 		switch (rdma_wr->type) {
3856 		case RDMA_WR_TYPE_SEND:
3857 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3858 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3859 
3860 			if (!wc[i].status) {
3861 				count++;
3862 				assert(wc[i].opcode == IBV_WC_SEND);
3863 				assert(nvmf_rdma_req_is_completing(rdma_req));
3864 			}
3865 
3866 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3867 			/* RDMA_WRITE operation completed. +1 since it was chained with rsp WR */
3868 			rqpair->current_send_depth -= rdma_req->num_outstanding_data_wr + 1;
3869 			rdma_req->num_outstanding_data_wr = 0;
3870 
3871 			nvmf_rdma_request_process(rtransport, rdma_req);
3872 			break;
3873 		case RDMA_WR_TYPE_RECV:
3874 			/* rdma_recv->qpair will be invalid if using an SRQ.  In that case we have to get the qpair from the wc. */
3875 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3876 			if (rpoller->srq != NULL) {
3877 				rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
3878 				/* It is possible that there are still some completions for destroyed QP
3879 				 * associated with SRQ. We just ignore these late completions and re-post
3880 				 * receive WRs back to SRQ.
3881 				 */
3882 				if (spdk_unlikely(NULL == rdma_recv->qpair)) {
3883 					struct ibv_recv_wr *bad_wr;
3884 					int rc;
3885 
3886 					rdma_recv->wr.next = NULL;
3887 					rc = ibv_post_srq_recv(rpoller->srq,
3888 							       &rdma_recv->wr,
3889 							       &bad_wr);
3890 					if (rc) {
3891 						SPDK_ERRLOG("Failed to re-post recv WR to SRQ, err %d\n", rc);
3892 					}
3893 					continue;
3894 				}
3895 			}
3896 			rqpair = rdma_recv->qpair;
3897 
3898 			assert(rqpair != NULL);
3899 			if (!wc[i].status) {
3900 				assert(wc[i].opcode == IBV_WC_RECV);
3901 				if (rqpair->current_recv_depth >= rqpair->max_queue_depth) {
3902 					nvmf_rdma_start_disconnect(rqpair);
3903 					break;
3904 				}
3905 			}
3906 
3907 			rdma_recv->wr.next = NULL;
3908 			rqpair->current_recv_depth++;
3909 			rdma_recv->receive_tsc = poll_tsc;
3910 			rpoller->stat.requests++;
3911 			STAILQ_INSERT_TAIL(&rqpair->resources->incoming_queue, rdma_recv, link);
3912 			break;
3913 		case RDMA_WR_TYPE_DATA:
3914 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3915 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3916 
3917 			assert(rdma_req->num_outstanding_data_wr > 0);
3918 
3919 			rqpair->current_send_depth--;
3920 			rdma_req->num_outstanding_data_wr--;
3921 			if (!wc[i].status) {
3922 				assert(wc[i].opcode == IBV_WC_RDMA_READ);
3923 				rqpair->current_read_depth--;
3924 				/* wait for all outstanding reads associated with the same rdma_req to complete before proceeding. */
3925 				if (rdma_req->num_outstanding_data_wr == 0) {
3926 					rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
3927 					nvmf_rdma_request_process(rtransport, rdma_req);
3928 				}
3929 			} else {
3930 				/* If the data transfer fails still force the queue into the error state,
3931 				 * if we were performing an RDMA_READ, we need to force the request into a
3932 				 * completed state since it wasn't linked to a send. However, in the RDMA_WRITE
3933 				 * case, we should wait for the SEND to complete. */
3934 				if (rdma_req->data.wr.opcode == IBV_WR_RDMA_READ) {
3935 					rqpair->current_read_depth--;
3936 					if (rdma_req->num_outstanding_data_wr == 0) {
3937 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3938 					}
3939 				}
3940 			}
3941 			break;
3942 		default:
3943 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
3944 			continue;
3945 		}
3946 
3947 		/* Handle error conditions */
3948 		if (wc[i].status) {
3949 			if ((rdma_wr->type == RDMA_WR_TYPE_RECV && !rpoller->srq)) {
3950 				/* When we don't use SRQ and close a qpair, we will receive completions with error
3951 				 * status for all posted ibv_recv_wrs. This is expected and we don't want to log
3952 				 * an error in that case. */
3953 				SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Error on CQ %p, request 0x%lu, type %d, status: (%d): %s\n",
3954 					      rpoller->cq, wc[i].wr_id, rdma_wr->type, wc[i].status, ibv_wc_status_str(wc[i].status));
3955 			} else {
3956 				SPDK_ERRLOG("Error on CQ %p, request 0x%lu, type %d, status: (%d): %s\n",
3957 					    rpoller->cq, wc[i].wr_id, rdma_wr->type, wc[i].status, ibv_wc_status_str(wc[i].status));
3958 			}
3959 
3960 			error = true;
3961 
3962 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3963 				/* Disconnect the connection. */
3964 				nvmf_rdma_start_disconnect(rqpair);
3965 			} else {
3966 				nvmf_rdma_destroy_drained_qpair(rqpair);
3967 			}
3968 			continue;
3969 		}
3970 
3971 		nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3972 
3973 		if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
3974 			nvmf_rdma_destroy_drained_qpair(rqpair);
3975 		}
3976 	}
3977 
3978 	if (error == true) {
3979 		return -1;
3980 	}
3981 
3982 	/* submit outstanding work requests. */
3983 	_poller_submit_recvs(rtransport, rpoller);
3984 	_poller_submit_sends(rtransport, rpoller);
3985 
3986 	return count;
3987 }
3988 
3989 static int
3990 nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3991 {
3992 	struct spdk_nvmf_rdma_transport *rtransport;
3993 	struct spdk_nvmf_rdma_poll_group *rgroup;
3994 	struct spdk_nvmf_rdma_poller	*rpoller;
3995 	int				count, rc;
3996 
3997 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
3998 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3999 
4000 	count = 0;
4001 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4002 		rc = nvmf_rdma_poller_poll(rtransport, rpoller);
4003 		if (rc < 0) {
4004 			return rc;
4005 		}
4006 		count += rc;
4007 	}
4008 
4009 	return count;
4010 }
4011 
4012 static int
4013 nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
4014 			  struct spdk_nvme_transport_id *trid,
4015 			  bool peer)
4016 {
4017 	struct sockaddr *saddr;
4018 	uint16_t port;
4019 
4020 	spdk_nvme_trid_populate_transport(trid, SPDK_NVME_TRANSPORT_RDMA);
4021 
4022 	if (peer) {
4023 		saddr = rdma_get_peer_addr(id);
4024 	} else {
4025 		saddr = rdma_get_local_addr(id);
4026 	}
4027 	switch (saddr->sa_family) {
4028 	case AF_INET: {
4029 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
4030 
4031 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
4032 		inet_ntop(AF_INET, &saddr_in->sin_addr,
4033 			  trid->traddr, sizeof(trid->traddr));
4034 		if (peer) {
4035 			port = ntohs(rdma_get_dst_port(id));
4036 		} else {
4037 			port = ntohs(rdma_get_src_port(id));
4038 		}
4039 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
4040 		break;
4041 	}
4042 	case AF_INET6: {
4043 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
4044 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
4045 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
4046 			  trid->traddr, sizeof(trid->traddr));
4047 		if (peer) {
4048 			port = ntohs(rdma_get_dst_port(id));
4049 		} else {
4050 			port = ntohs(rdma_get_src_port(id));
4051 		}
4052 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
4053 		break;
4054 	}
4055 	default:
4056 		return -1;
4057 
4058 	}
4059 
4060 	return 0;
4061 }
4062 
4063 static int
4064 nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
4065 			      struct spdk_nvme_transport_id *trid)
4066 {
4067 	struct spdk_nvmf_rdma_qpair	*rqpair;
4068 
4069 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4070 
4071 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
4072 }
4073 
4074 static int
4075 nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
4076 			       struct spdk_nvme_transport_id *trid)
4077 {
4078 	struct spdk_nvmf_rdma_qpair	*rqpair;
4079 
4080 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4081 
4082 	return nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
4083 }
4084 
4085 static int
4086 nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
4087 				struct spdk_nvme_transport_id *trid)
4088 {
4089 	struct spdk_nvmf_rdma_qpair	*rqpair;
4090 
4091 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4092 
4093 	return nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
4094 }
4095 
4096 void
4097 spdk_nvmf_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
4098 {
4099 	g_nvmf_hooks = *hooks;
4100 }
4101 
4102 static void
4103 nvmf_rdma_request_set_abort_status(struct spdk_nvmf_request *req,
4104 				   struct spdk_nvmf_rdma_request *rdma_req_to_abort)
4105 {
4106 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
4107 	rdma_req_to_abort->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_BY_REQUEST;
4108 
4109 	rdma_req_to_abort->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
4110 
4111 	req->rsp->nvme_cpl.cdw0 &= ~1U;	/* Command was successfully aborted. */
4112 }
4113 
4114 static int
4115 _nvmf_rdma_qpair_abort_request(void *ctx)
4116 {
4117 	struct spdk_nvmf_request *req = ctx;
4118 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = SPDK_CONTAINEROF(
4119 				req->req_to_abort, struct spdk_nvmf_rdma_request, req);
4120 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(req->req_to_abort->qpair,
4121 					      struct spdk_nvmf_rdma_qpair, qpair);
4122 	int rc;
4123 
4124 	spdk_poller_unregister(&req->poller);
4125 
4126 	switch (rdma_req_to_abort->state) {
4127 	case RDMA_REQUEST_STATE_EXECUTING:
4128 		rc = nvmf_ctrlr_abort_request(req);
4129 		if (rc == SPDK_NVMF_REQUEST_EXEC_STATUS_ASYNCHRONOUS) {
4130 			return SPDK_POLLER_BUSY;
4131 		}
4132 		break;
4133 
4134 	case RDMA_REQUEST_STATE_NEED_BUFFER:
4135 		STAILQ_REMOVE(&rqpair->poller->group->group.pending_buf_queue,
4136 			      &rdma_req_to_abort->req, spdk_nvmf_request, buf_link);
4137 
4138 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4139 		break;
4140 
4141 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
4142 		STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req_to_abort,
4143 			      spdk_nvmf_rdma_request, state_link);
4144 
4145 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4146 		break;
4147 
4148 	case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
4149 		STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req_to_abort,
4150 			      spdk_nvmf_rdma_request, state_link);
4151 
4152 		nvmf_rdma_request_set_abort_status(req, rdma_req_to_abort);
4153 		break;
4154 
4155 	case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
4156 		if (spdk_get_ticks() < req->timeout_tsc) {
4157 			req->poller = SPDK_POLLER_REGISTER(_nvmf_rdma_qpair_abort_request, req, 0);
4158 			return SPDK_POLLER_BUSY;
4159 		}
4160 		break;
4161 
4162 	default:
4163 		break;
4164 	}
4165 
4166 	spdk_nvmf_request_complete(req);
4167 	return SPDK_POLLER_BUSY;
4168 }
4169 
4170 static void
4171 nvmf_rdma_qpair_abort_request(struct spdk_nvmf_qpair *qpair,
4172 			      struct spdk_nvmf_request *req)
4173 {
4174 	struct spdk_nvmf_rdma_qpair *rqpair;
4175 	struct spdk_nvmf_rdma_transport *rtransport;
4176 	struct spdk_nvmf_transport *transport;
4177 	uint16_t cid;
4178 	uint32_t i;
4179 	struct spdk_nvmf_rdma_request *rdma_req_to_abort = NULL;
4180 
4181 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4182 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
4183 	transport = &rtransport->transport;
4184 
4185 	cid = req->cmd->nvme_cmd.cdw10_bits.abort.cid;
4186 
4187 	for (i = 0; i < rqpair->max_queue_depth; i++) {
4188 		rdma_req_to_abort = &rqpair->resources->reqs[i];
4189 
4190 		if (rdma_req_to_abort->state != RDMA_REQUEST_STATE_FREE &&
4191 		    rdma_req_to_abort->req.cmd->nvme_cmd.cid == cid) {
4192 			break;
4193 		}
4194 	}
4195 
4196 	if (rdma_req_to_abort == NULL) {
4197 		spdk_nvmf_request_complete(req);
4198 		return;
4199 	}
4200 
4201 	req->req_to_abort = &rdma_req_to_abort->req;
4202 	req->timeout_tsc = spdk_get_ticks() +
4203 			   transport->opts.abort_timeout_sec * spdk_get_ticks_hz();
4204 	req->poller = NULL;
4205 
4206 	_nvmf_rdma_qpair_abort_request(req);
4207 }
4208 
4209 static int
4210 nvmf_rdma_poll_group_get_stat(struct spdk_nvmf_tgt *tgt,
4211 			      struct spdk_nvmf_transport_poll_group_stat **stat)
4212 {
4213 	struct spdk_io_channel *ch;
4214 	struct spdk_nvmf_poll_group *group;
4215 	struct spdk_nvmf_transport_poll_group *tgroup;
4216 	struct spdk_nvmf_rdma_poll_group *rgroup;
4217 	struct spdk_nvmf_rdma_poller *rpoller;
4218 	struct spdk_nvmf_rdma_device_stat *device_stat;
4219 	uint64_t num_devices = 0;
4220 
4221 	if (tgt == NULL || stat == NULL) {
4222 		return -EINVAL;
4223 	}
4224 
4225 	ch = spdk_get_io_channel(tgt);
4226 	group = spdk_io_channel_get_ctx(ch);;
4227 	spdk_put_io_channel(ch);
4228 	TAILQ_FOREACH(tgroup, &group->tgroups, link) {
4229 		if (SPDK_NVME_TRANSPORT_RDMA == tgroup->transport->ops->type) {
4230 			*stat = calloc(1, sizeof(struct spdk_nvmf_transport_poll_group_stat));
4231 			if (!*stat) {
4232 				SPDK_ERRLOG("Failed to allocate memory for NVMf RDMA statistics\n");
4233 				return -ENOMEM;
4234 			}
4235 			(*stat)->trtype = SPDK_NVME_TRANSPORT_RDMA;
4236 
4237 			rgroup = SPDK_CONTAINEROF(tgroup, struct spdk_nvmf_rdma_poll_group, group);
4238 			/* Count devices to allocate enough memory */
4239 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4240 				++num_devices;
4241 			}
4242 			(*stat)->rdma.devices = calloc(num_devices, sizeof(struct spdk_nvmf_rdma_device_stat));
4243 			if (!(*stat)->rdma.devices) {
4244 				SPDK_ERRLOG("Failed to allocate NVMf RDMA devices statistics\n");
4245 				free(*stat);
4246 				return -ENOMEM;
4247 			}
4248 
4249 			(*stat)->rdma.pending_data_buffer = rgroup->stat.pending_data_buffer;
4250 			(*stat)->rdma.num_devices = num_devices;
4251 			num_devices = 0;
4252 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4253 				device_stat = &(*stat)->rdma.devices[num_devices++];
4254 				device_stat->name = ibv_get_device_name(rpoller->device->context->device);
4255 				device_stat->polls = rpoller->stat.polls;
4256 				device_stat->completions = rpoller->stat.completions;
4257 				device_stat->requests = rpoller->stat.requests;
4258 				device_stat->request_latency = rpoller->stat.request_latency;
4259 				device_stat->pending_free_request = rpoller->stat.pending_free_request;
4260 				device_stat->pending_rdma_read = rpoller->stat.pending_rdma_read;
4261 				device_stat->pending_rdma_write = rpoller->stat.pending_rdma_write;
4262 			}
4263 			return 0;
4264 		}
4265 	}
4266 	return -ENOENT;
4267 }
4268 
4269 static void
4270 nvmf_rdma_poll_group_free_stat(struct spdk_nvmf_transport_poll_group_stat *stat)
4271 {
4272 	if (stat) {
4273 		free(stat->rdma.devices);
4274 	}
4275 	free(stat);
4276 }
4277 
4278 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
4279 	.name = "RDMA",
4280 	.type = SPDK_NVME_TRANSPORT_RDMA,
4281 	.opts_init = nvmf_rdma_opts_init,
4282 	.create = nvmf_rdma_create,
4283 	.destroy = nvmf_rdma_destroy,
4284 
4285 	.listen = nvmf_rdma_listen,
4286 	.stop_listen = nvmf_rdma_stop_listen,
4287 	.accept = nvmf_rdma_accept,
4288 	.cdata_init = nvmf_rdma_cdata_init,
4289 
4290 	.listener_discover = nvmf_rdma_discover,
4291 
4292 	.poll_group_create = nvmf_rdma_poll_group_create,
4293 	.get_optimal_poll_group = nvmf_rdma_get_optimal_poll_group,
4294 	.poll_group_destroy = nvmf_rdma_poll_group_destroy,
4295 	.poll_group_add = nvmf_rdma_poll_group_add,
4296 	.poll_group_remove = nvmf_rdma_poll_group_remove,
4297 	.poll_group_poll = nvmf_rdma_poll_group_poll,
4298 
4299 	.req_free = nvmf_rdma_request_free,
4300 	.req_complete = nvmf_rdma_request_complete,
4301 
4302 	.qpair_fini = nvmf_rdma_close_qpair,
4303 	.qpair_get_peer_trid = nvmf_rdma_qpair_get_peer_trid,
4304 	.qpair_get_local_trid = nvmf_rdma_qpair_get_local_trid,
4305 	.qpair_get_listen_trid = nvmf_rdma_qpair_get_listen_trid,
4306 	.qpair_abort_request = nvmf_rdma_qpair_abort_request,
4307 
4308 	.poll_group_get_stat = nvmf_rdma_poll_group_get_stat,
4309 	.poll_group_free_stat = nvmf_rdma_poll_group_free_stat,
4310 };
4311 
4312 SPDK_NVMF_TRANSPORT_REGISTER(rdma, &spdk_nvmf_transport_rdma);
4313 SPDK_LOG_REGISTER_COMPONENT("rdma", SPDK_LOG_RDMA)
4314