xref: /spdk/lib/nvmf/rdma.c (revision 0ed66e7ef6965ba59db2c57aa64e9898f12c302d)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2018 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 <infiniband/verbs.h>
37 #include <rdma/rdma_cma.h>
38 #include <rdma/rdma_verbs.h>
39 
40 #include "nvmf_internal.h"
41 #include "transport.h"
42 
43 #include "spdk/config.h"
44 #include "spdk/assert.h"
45 #include "spdk/thread.h"
46 #include "spdk/nvmf.h"
47 #include "spdk/nvmf_spec.h"
48 #include "spdk/string.h"
49 #include "spdk/trace.h"
50 #include "spdk/util.h"
51 
52 #include "spdk_internal/log.h"
53 
54 struct spdk_nvme_rdma_hooks g_nvmf_hooks = {};
55 
56 /*
57  RDMA Connection Resource Defaults
58  */
59 #define NVMF_DEFAULT_TX_SGE		SPDK_NVMF_MAX_SGL_ENTRIES
60 #define NVMF_DEFAULT_RSP_SGE		1
61 #define NVMF_DEFAULT_RX_SGE		2
62 
63 /* The RDMA completion queue size */
64 #define DEFAULT_NVMF_RDMA_CQ_SIZE	4096
65 #define MAX_WR_PER_QP(queue_depth)	(queue_depth * 3 + 2)
66 
67 /* Timeout for destroying defunct rqpairs */
68 #define NVMF_RDMA_QPAIR_DESTROY_TIMEOUT_US 4000000
69 
70 enum spdk_nvmf_rdma_request_state {
71 	/* The request is not currently in use */
72 	RDMA_REQUEST_STATE_FREE = 0,
73 
74 	/* Initial state when request first received */
75 	RDMA_REQUEST_STATE_NEW,
76 
77 	/* The request is queued until a data buffer is available. */
78 	RDMA_REQUEST_STATE_NEED_BUFFER,
79 
80 	/* The request is waiting on RDMA queue depth availability
81 	 * to transfer data from the host to the controller.
82 	 */
83 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
84 
85 	/* The request is currently transferring data from the host to the controller. */
86 	RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
87 
88 	/* The request is ready to execute at the block device */
89 	RDMA_REQUEST_STATE_READY_TO_EXECUTE,
90 
91 	/* The request is currently executing at the block device */
92 	RDMA_REQUEST_STATE_EXECUTING,
93 
94 	/* The request finished executing at the block device */
95 	RDMA_REQUEST_STATE_EXECUTED,
96 
97 	/* The request is waiting on RDMA queue depth availability
98 	 * to transfer data from the controller to the host.
99 	 */
100 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
101 
102 	/* The request is ready to send a completion */
103 	RDMA_REQUEST_STATE_READY_TO_COMPLETE,
104 
105 	/* The request is currently transferring data from the controller to the host. */
106 	RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
107 
108 	/* The request currently has an outstanding completion without an
109 	 * associated data transfer.
110 	 */
111 	RDMA_REQUEST_STATE_COMPLETING,
112 
113 	/* The request completed and can be marked free. */
114 	RDMA_REQUEST_STATE_COMPLETED,
115 
116 	/* Terminator */
117 	RDMA_REQUEST_NUM_STATES,
118 };
119 
120 #define OBJECT_NVMF_RDMA_IO				0x40
121 
122 #define TRACE_GROUP_NVMF_RDMA				0x4
123 #define TRACE_RDMA_REQUEST_STATE_NEW					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x0)
124 #define TRACE_RDMA_REQUEST_STATE_NEED_BUFFER				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x1)
125 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x2)
126 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x3)
127 #define TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x4)
128 #define TRACE_RDMA_REQUEST_STATE_EXECUTING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x5)
129 #define TRACE_RDMA_REQUEST_STATE_EXECUTED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x6)
130 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING		SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x7)
131 #define TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x8)
132 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x9)
133 #define TRACE_RDMA_REQUEST_STATE_COMPLETING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xA)
134 #define TRACE_RDMA_REQUEST_STATE_COMPLETED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xB)
135 #define TRACE_RDMA_QP_CREATE						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xC)
136 #define TRACE_RDMA_IBV_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xD)
137 #define TRACE_RDMA_CM_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xE)
138 #define TRACE_RDMA_QP_STATE_CHANGE					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xF)
139 #define TRACE_RDMA_QP_DISCONNECT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x10)
140 #define TRACE_RDMA_QP_DESTROY						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x11)
141 
142 SPDK_TRACE_REGISTER_FN(nvmf_trace, "nvmf_rdma", TRACE_GROUP_NVMF_RDMA)
143 {
144 	spdk_trace_register_object(OBJECT_NVMF_RDMA_IO, 'r');
145 	spdk_trace_register_description("RDMA_REQ_NEW", "",
146 					TRACE_RDMA_REQUEST_STATE_NEW,
147 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 1, 1, "cmid:   ");
148 	spdk_trace_register_description("RDMA_REQ_NEED_BUFFER", "",
149 					TRACE_RDMA_REQUEST_STATE_NEED_BUFFER,
150 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
151 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_C_TO_H", "",
152 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
153 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
154 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_H_TO_C", "",
155 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
156 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
157 	spdk_trace_register_description("RDMA_REQ_TX_H_TO_C", "",
158 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
159 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
160 	spdk_trace_register_description("RDMA_REQ_RDY_TO_EXECUTE", "",
161 					TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE,
162 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
163 	spdk_trace_register_description("RDMA_REQ_EXECUTING", "",
164 					TRACE_RDMA_REQUEST_STATE_EXECUTING,
165 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
166 	spdk_trace_register_description("RDMA_REQ_EXECUTED", "",
167 					TRACE_RDMA_REQUEST_STATE_EXECUTED,
168 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
169 	spdk_trace_register_description("RDMA_REQ_RDY_TO_COMPLETE", "",
170 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE,
171 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
172 	spdk_trace_register_description("RDMA_REQ_COMPLETING_CONTROLLER_TO_HOST", "",
173 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
174 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
175 	spdk_trace_register_description("RDMA_REQ_COMPLETING_INCAPSULE", "",
176 					TRACE_RDMA_REQUEST_STATE_COMPLETING,
177 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
178 	spdk_trace_register_description("RDMA_REQ_COMPLETED", "",
179 					TRACE_RDMA_REQUEST_STATE_COMPLETED,
180 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
181 
182 	spdk_trace_register_description("RDMA_QP_CREATE", "", TRACE_RDMA_QP_CREATE,
183 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
184 	spdk_trace_register_description("RDMA_IBV_ASYNC_EVENT", "", TRACE_RDMA_IBV_ASYNC_EVENT,
185 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
186 	spdk_trace_register_description("RDMA_CM_ASYNC_EVENT", "", TRACE_RDMA_CM_ASYNC_EVENT,
187 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
188 	spdk_trace_register_description("RDMA_QP_STATE_CHANGE", "", TRACE_RDMA_QP_STATE_CHANGE,
189 					OWNER_NONE, OBJECT_NONE, 0, 1, "state:  ");
190 	spdk_trace_register_description("RDMA_QP_DISCONNECT", "", TRACE_RDMA_QP_DISCONNECT,
191 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
192 	spdk_trace_register_description("RDMA_QP_DESTROY", "", TRACE_RDMA_QP_DESTROY,
193 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
194 }
195 
196 enum spdk_nvmf_rdma_wr_type {
197 	RDMA_WR_TYPE_RECV,
198 	RDMA_WR_TYPE_SEND,
199 	RDMA_WR_TYPE_DATA,
200 };
201 
202 struct spdk_nvmf_rdma_wr {
203 	enum spdk_nvmf_rdma_wr_type	type;
204 };
205 
206 /* This structure holds commands as they are received off the wire.
207  * It must be dynamically paired with a full request object
208  * (spdk_nvmf_rdma_request) to service a request. It is separate
209  * from the request because RDMA does not appear to order
210  * completions, so occasionally we'll get a new incoming
211  * command when there aren't any free request objects.
212  */
213 struct spdk_nvmf_rdma_recv {
214 	struct ibv_recv_wr			wr;
215 	struct ibv_sge				sgl[NVMF_DEFAULT_RX_SGE];
216 
217 	struct spdk_nvmf_rdma_qpair		*qpair;
218 
219 	/* In-capsule data buffer */
220 	uint8_t					*buf;
221 
222 	struct spdk_nvmf_rdma_wr		rdma_wr;
223 
224 	STAILQ_ENTRY(spdk_nvmf_rdma_recv)	link;
225 };
226 
227 struct spdk_nvmf_rdma_request_data {
228 	struct spdk_nvmf_rdma_wr	rdma_wr;
229 	struct ibv_send_wr		wr;
230 	struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
231 	void				*buffers[SPDK_NVMF_MAX_SGL_ENTRIES];
232 };
233 
234 struct spdk_nvmf_rdma_request {
235 	struct spdk_nvmf_request		req;
236 	bool					data_from_pool;
237 
238 	enum spdk_nvmf_rdma_request_state	state;
239 
240 	struct spdk_nvmf_rdma_recv		*recv;
241 
242 	struct {
243 		struct spdk_nvmf_rdma_wr	rdma_wr;
244 		struct	ibv_send_wr		wr;
245 		struct	ibv_sge			sgl[NVMF_DEFAULT_RSP_SGE];
246 	} rsp;
247 
248 	struct spdk_nvmf_rdma_request_data	data;
249 
250 	uint32_t				num_outstanding_data_wr;
251 
252 	TAILQ_ENTRY(spdk_nvmf_rdma_request)	link;
253 	STAILQ_ENTRY(spdk_nvmf_rdma_request)	state_link;
254 };
255 
256 enum spdk_nvmf_rdma_qpair_disconnect_flags {
257 	RDMA_QP_DISCONNECTING		= 1,
258 	RDMA_QP_RECV_DRAINED		= 1 << 1,
259 	RDMA_QP_SEND_DRAINED		= 1 << 2
260 };
261 
262 struct spdk_nvmf_rdma_resource_opts {
263 	struct spdk_nvmf_rdma_qpair	*qpair;
264 	/* qp points either to an ibv_qp object or an ibv_srq object depending on the value of shared. */
265 	void				*qp;
266 	struct ibv_pd			*pd;
267 	uint32_t			max_queue_depth;
268 	uint32_t			in_capsule_data_size;
269 	bool				shared;
270 };
271 
272 struct spdk_nvmf_rdma_resources {
273 	/* Array of size "max_queue_depth" containing RDMA requests. */
274 	struct spdk_nvmf_rdma_request		*reqs;
275 
276 	/* Array of size "max_queue_depth" containing RDMA recvs. */
277 	struct spdk_nvmf_rdma_recv		*recvs;
278 
279 	/* Array of size "max_queue_depth" containing 64 byte capsules
280 	 * used for receive.
281 	 */
282 	union nvmf_h2c_msg			*cmds;
283 	struct ibv_mr				*cmds_mr;
284 
285 	/* Array of size "max_queue_depth" containing 16 byte completions
286 	 * to be sent back to the user.
287 	 */
288 	union nvmf_c2h_msg			*cpls;
289 	struct ibv_mr				*cpls_mr;
290 
291 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
292 	 * buffers to be used for in capsule data.
293 	 */
294 	void					*bufs;
295 	struct ibv_mr				*bufs_mr;
296 
297 	/* Receives that are waiting for a request object */
298 	STAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
299 
300 	/* Queue to track free requests */
301 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	free_queue;
302 };
303 
304 struct spdk_nvmf_rdma_qpair {
305 	struct spdk_nvmf_qpair			qpair;
306 
307 	struct spdk_nvmf_rdma_port		*port;
308 	struct spdk_nvmf_rdma_poller		*poller;
309 
310 	struct rdma_cm_id			*cm_id;
311 	struct ibv_srq				*srq;
312 	struct rdma_cm_id			*listen_id;
313 
314 	/* The maximum number of I/O outstanding on this connection at one time */
315 	uint16_t				max_queue_depth;
316 
317 	/* The maximum number of active RDMA READ and ATOMIC operations at one time */
318 	uint16_t				max_read_depth;
319 
320 	/* The maximum number of RDMA SEND operations at one time */
321 	uint32_t				max_send_depth;
322 
323 	/* The current number of outstanding WRs from this qpair's
324 	 * recv queue. Should not exceed device->attr.max_queue_depth.
325 	 */
326 	uint16_t				current_recv_depth;
327 
328 	/* The current number of posted WRs from this qpair's
329 	 * send queue. Should not exceed max_send_depth.
330 	 */
331 	uint32_t				current_send_depth;
332 
333 	/* The current number of active RDMA READ operations */
334 	uint16_t				current_read_depth;
335 
336 	/* The maximum number of SGEs per WR on the send queue */
337 	uint32_t				max_send_sge;
338 
339 	/* The maximum number of SGEs per WR on the recv queue */
340 	uint32_t				max_recv_sge;
341 
342 	struct spdk_nvmf_rdma_resources		*resources;
343 
344 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_read_queue;
345 
346 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_write_queue;
347 
348 	/* Number of requests not in the free state */
349 	uint32_t				qd;
350 
351 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	link;
352 
353 	/* IBV queue pair attributes: they are used to manage
354 	 * qp state and recover from errors.
355 	 */
356 	struct ibv_qp_attr			ibv_attr;
357 
358 	uint32_t				disconnect_flags;
359 
360 	/* Poller registered in case the qpair doesn't properly
361 	 * complete the qpair destruct process and becomes defunct.
362 	 */
363 
364 	struct spdk_poller			*destruct_poller;
365 
366 	/* There are several ways a disconnect can start on a qpair
367 	 * and they are not all mutually exclusive. It is important
368 	 * that we only initialize one of these paths.
369 	 */
370 	bool					disconnect_started;
371 	/* Lets us know that we have received the last_wqe event. */
372 	bool					last_wqe_reached;
373 };
374 
375 struct spdk_nvmf_rdma_poller {
376 	struct spdk_nvmf_rdma_device		*device;
377 	struct spdk_nvmf_rdma_poll_group	*group;
378 
379 	int					num_cqe;
380 	int					required_num_wr;
381 	struct ibv_cq				*cq;
382 
383 	/* The maximum number of I/O outstanding on the shared receive queue at one time */
384 	uint16_t				max_srq_depth;
385 
386 	/* Shared receive queue */
387 	struct ibv_srq				*srq;
388 
389 	struct spdk_nvmf_rdma_resources		*resources;
390 
391 	TAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs;
392 
393 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
394 };
395 
396 struct spdk_nvmf_rdma_poll_group {
397 	struct spdk_nvmf_transport_poll_group	group;
398 
399 	/* Requests that are waiting to obtain a data buffer */
400 	TAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_data_buf_queue;
401 
402 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)	pollers;
403 };
404 
405 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
406 struct spdk_nvmf_rdma_device {
407 	struct ibv_device_attr			attr;
408 	struct ibv_context			*context;
409 
410 	struct spdk_mem_map			*map;
411 	struct ibv_pd				*pd;
412 
413 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
414 };
415 
416 struct spdk_nvmf_rdma_port {
417 	struct spdk_nvme_transport_id		trid;
418 	struct rdma_cm_id			*id;
419 	struct spdk_nvmf_rdma_device		*device;
420 	uint32_t				ref;
421 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
422 };
423 
424 struct spdk_nvmf_rdma_transport {
425 	struct spdk_nvmf_transport	transport;
426 
427 	struct rdma_event_channel	*event_channel;
428 
429 	struct spdk_mempool		*data_wr_pool;
430 
431 	pthread_mutex_t			lock;
432 
433 	/* fields used to poll RDMA/IB events */
434 	nfds_t			npoll_fds;
435 	struct pollfd		*poll_fds;
436 
437 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
438 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
439 };
440 
441 static inline int
442 spdk_nvmf_rdma_check_ibv_state(enum ibv_qp_state state)
443 {
444 	switch (state) {
445 	case IBV_QPS_RESET:
446 	case IBV_QPS_INIT:
447 	case IBV_QPS_RTR:
448 	case IBV_QPS_RTS:
449 	case IBV_QPS_SQD:
450 	case IBV_QPS_SQE:
451 	case IBV_QPS_ERR:
452 		return 0;
453 	default:
454 		return -1;
455 	}
456 }
457 
458 static enum ibv_qp_state
459 spdk_nvmf_rdma_update_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair) {
460 	enum ibv_qp_state old_state, new_state;
461 	struct ibv_qp_init_attr init_attr;
462 	int rc;
463 
464 	/* All the attributes needed for recovery */
465 	static int spdk_nvmf_ibv_attr_mask =
466 	IBV_QP_STATE |
467 	IBV_QP_PKEY_INDEX |
468 	IBV_QP_PORT |
469 	IBV_QP_ACCESS_FLAGS |
470 	IBV_QP_AV |
471 	IBV_QP_PATH_MTU |
472 	IBV_QP_DEST_QPN |
473 	IBV_QP_RQ_PSN |
474 	IBV_QP_MAX_DEST_RD_ATOMIC |
475 	IBV_QP_MIN_RNR_TIMER |
476 	IBV_QP_SQ_PSN |
477 	IBV_QP_TIMEOUT |
478 	IBV_QP_RETRY_CNT |
479 	IBV_QP_RNR_RETRY |
480 	IBV_QP_MAX_QP_RD_ATOMIC;
481 
482 	old_state = rqpair->ibv_attr.qp_state;
483 	rc = ibv_query_qp(rqpair->cm_id->qp, &rqpair->ibv_attr,
484 			  spdk_nvmf_ibv_attr_mask, &init_attr);
485 
486 	if (rc)
487 	{
488 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
489 		assert(false);
490 	}
491 
492 	new_state = rqpair->ibv_attr.qp_state;
493 
494 	rc = spdk_nvmf_rdma_check_ibv_state(new_state);
495 	if (rc)
496 	{
497 		SPDK_ERRLOG("QP#%d: bad state updated: %u, maybe hardware issue\n", rqpair->qpair.qid, new_state);
498 		/*
499 		 * IBV_QPS_UNKNOWN undefined if lib version smaller than libibverbs-1.1.8
500 		 * IBV_QPS_UNKNOWN is the enum element after IBV_QPS_ERR
501 		 */
502 		return IBV_QPS_ERR + 1;
503 	}
504 
505 	if (old_state != new_state)
506 	{
507 		spdk_trace_record(TRACE_RDMA_QP_STATE_CHANGE, 0, 0,
508 				  (uintptr_t)rqpair->cm_id, new_state);
509 	}
510 	return new_state;
511 }
512 
513 static const char *str_ibv_qp_state[] = {
514 	"IBV_QPS_RESET",
515 	"IBV_QPS_INIT",
516 	"IBV_QPS_RTR",
517 	"IBV_QPS_RTS",
518 	"IBV_QPS_SQD",
519 	"IBV_QPS_SQE",
520 	"IBV_QPS_ERR",
521 	"IBV_QPS_UNKNOWN"
522 };
523 
524 static int
525 spdk_nvmf_rdma_set_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair,
526 			     enum ibv_qp_state new_state)
527 {
528 	int rc;
529 	enum ibv_qp_state state;
530 	static int attr_mask_rc[] = {
531 		[IBV_QPS_RESET] = IBV_QP_STATE,
532 		[IBV_QPS_INIT] = (IBV_QP_STATE |
533 				  IBV_QP_PKEY_INDEX |
534 				  IBV_QP_PORT |
535 				  IBV_QP_ACCESS_FLAGS),
536 		[IBV_QPS_RTR] = (IBV_QP_STATE |
537 				 IBV_QP_AV |
538 				 IBV_QP_PATH_MTU |
539 				 IBV_QP_DEST_QPN |
540 				 IBV_QP_RQ_PSN |
541 				 IBV_QP_MAX_DEST_RD_ATOMIC |
542 				 IBV_QP_MIN_RNR_TIMER),
543 		[IBV_QPS_RTS] = (IBV_QP_STATE |
544 				 IBV_QP_SQ_PSN |
545 				 IBV_QP_TIMEOUT |
546 				 IBV_QP_RETRY_CNT |
547 				 IBV_QP_RNR_RETRY |
548 				 IBV_QP_MAX_QP_RD_ATOMIC),
549 		[IBV_QPS_SQD] = IBV_QP_STATE,
550 		[IBV_QPS_SQE] = IBV_QP_STATE,
551 		[IBV_QPS_ERR] = IBV_QP_STATE,
552 	};
553 
554 	rc = spdk_nvmf_rdma_check_ibv_state(new_state);
555 	if (rc) {
556 		SPDK_ERRLOG("QP#%d: bad state requested: %u\n",
557 			    rqpair->qpair.qid, new_state);
558 		return rc;
559 	}
560 
561 	rqpair->ibv_attr.cur_qp_state = rqpair->ibv_attr.qp_state;
562 	rqpair->ibv_attr.qp_state = new_state;
563 	rqpair->ibv_attr.ah_attr.port_num = rqpair->ibv_attr.port_num;
564 
565 	rc = ibv_modify_qp(rqpair->cm_id->qp, &rqpair->ibv_attr,
566 			   attr_mask_rc[new_state]);
567 
568 	if (rc) {
569 		SPDK_ERRLOG("QP#%d: failed to set state to: %s, %d (%s)\n",
570 			    rqpair->qpair.qid, str_ibv_qp_state[new_state], errno, strerror(errno));
571 		return rc;
572 	}
573 
574 	state = spdk_nvmf_rdma_update_ibv_state(rqpair);
575 
576 	if (state != new_state) {
577 		SPDK_ERRLOG("QP#%d: expected state: %s, actual state: %s\n",
578 			    rqpair->qpair.qid, str_ibv_qp_state[new_state],
579 			    str_ibv_qp_state[state]);
580 		return -1;
581 	}
582 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "IBV QP#%u changed to: %s\n", rqpair->qpair.qid,
583 		      str_ibv_qp_state[state]);
584 	return 0;
585 }
586 
587 static void
588 nvmf_rdma_dump_request(struct spdk_nvmf_rdma_request *req)
589 {
590 	SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", req->data_from_pool);
591 	if (req->req.cmd) {
592 		SPDK_ERRLOG("\t\tRequest opcode: %d\n", req->req.cmd->nvmf_cmd.opcode);
593 	}
594 	if (req->recv) {
595 		SPDK_ERRLOG("\t\tRequest recv wr_id%lu\n", req->recv->wr.wr_id);
596 	}
597 }
598 
599 static void
600 nvmf_rdma_dump_qpair_contents(struct spdk_nvmf_rdma_qpair *rqpair)
601 {
602 	int i;
603 
604 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", rqpair->qpair.qid);
605 	for (i = 0; i < rqpair->max_queue_depth; i++) {
606 		if (rqpair->resources->reqs[i].state != RDMA_REQUEST_STATE_FREE) {
607 			nvmf_rdma_dump_request(&rqpair->resources->reqs[i]);
608 		}
609 	}
610 }
611 
612 static void
613 nvmf_rdma_resources_destroy(struct spdk_nvmf_rdma_resources *resources)
614 {
615 	if (resources->cmds_mr) {
616 		ibv_dereg_mr(resources->cmds_mr);
617 	}
618 
619 	if (resources->cpls_mr) {
620 		ibv_dereg_mr(resources->cpls_mr);
621 	}
622 
623 	if (resources->bufs_mr) {
624 		ibv_dereg_mr(resources->bufs_mr);
625 	}
626 
627 	spdk_dma_free(resources->cmds);
628 	spdk_dma_free(resources->cpls);
629 	spdk_dma_free(resources->bufs);
630 	free(resources->reqs);
631 	free(resources->recvs);
632 	free(resources);
633 }
634 
635 
636 static struct spdk_nvmf_rdma_resources *
637 nvmf_rdma_resources_create(struct spdk_nvmf_rdma_resource_opts *opts)
638 {
639 	struct spdk_nvmf_rdma_resources	*resources;
640 	struct spdk_nvmf_rdma_request	*rdma_req;
641 	struct spdk_nvmf_rdma_recv	*rdma_recv;
642 	struct ibv_qp			*qp;
643 	struct ibv_srq			*srq;
644 	uint32_t			i;
645 	int				rc;
646 
647 	resources = calloc(1, sizeof(struct spdk_nvmf_rdma_resources));
648 	if (!resources) {
649 		SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
650 		return NULL;
651 	}
652 
653 	resources->reqs = calloc(opts->max_queue_depth, sizeof(*resources->reqs));
654 	resources->recvs = calloc(opts->max_queue_depth, sizeof(*resources->recvs));
655 	resources->cmds = spdk_dma_zmalloc(opts->max_queue_depth * sizeof(*resources->cmds),
656 					   0x1000, NULL);
657 	resources->cpls = spdk_dma_zmalloc(opts->max_queue_depth * sizeof(*resources->cpls),
658 					   0x1000, NULL);
659 
660 	if (opts->in_capsule_data_size > 0) {
661 		resources->bufs = spdk_dma_zmalloc(opts->max_queue_depth *
662 						   opts->in_capsule_data_size,
663 						   0x1000, NULL);
664 	}
665 
666 	if (!resources->reqs || !resources->recvs || !resources->cmds ||
667 	    !resources->cpls || (opts->in_capsule_data_size && !resources->bufs)) {
668 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
669 		goto cleanup;
670 	}
671 
672 	resources->cmds_mr = ibv_reg_mr(opts->pd, resources->cmds,
673 					opts->max_queue_depth * sizeof(*resources->cmds),
674 					IBV_ACCESS_LOCAL_WRITE);
675 	resources->cpls_mr = ibv_reg_mr(opts->pd, resources->cpls,
676 					opts->max_queue_depth * sizeof(*resources->cpls),
677 					0);
678 
679 	if (opts->in_capsule_data_size) {
680 		resources->bufs_mr = ibv_reg_mr(opts->pd, resources->bufs,
681 						opts->max_queue_depth *
682 						opts->in_capsule_data_size,
683 						IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
684 	}
685 
686 	if (!resources->cmds_mr || !resources->cpls_mr ||
687 	    (opts->in_capsule_data_size &&
688 	     !resources->bufs_mr)) {
689 		goto cleanup;
690 	}
691 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Command Array: %p Length: %lx LKey: %x\n",
692 		      resources->cmds, opts->max_queue_depth * sizeof(*resources->cmds),
693 		      resources->cmds_mr->lkey);
694 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Completion Array: %p Length: %lx LKey: %x\n",
695 		      resources->cpls, opts->max_queue_depth * sizeof(*resources->cpls),
696 		      resources->cpls_mr->lkey);
697 	if (resources->bufs && resources->bufs_mr) {
698 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "In Capsule Data Array: %p Length: %x LKey: %x\n",
699 			      resources->bufs, opts->max_queue_depth *
700 			      opts->in_capsule_data_size, resources->bufs_mr->lkey);
701 	}
702 
703 	/* Initialize queues */
704 	STAILQ_INIT(&resources->incoming_queue);
705 	STAILQ_INIT(&resources->free_queue);
706 
707 	for (i = 0; i < opts->max_queue_depth; i++) {
708 		struct ibv_recv_wr *bad_wr = NULL;
709 
710 		rdma_recv = &resources->recvs[i];
711 		rdma_recv->qpair = opts->qpair;
712 
713 		/* Set up memory to receive commands */
714 		if (resources->bufs) {
715 			rdma_recv->buf = (void *)((uintptr_t)resources->bufs + (i *
716 						  opts->in_capsule_data_size));
717 		}
718 
719 		rdma_recv->rdma_wr.type = RDMA_WR_TYPE_RECV;
720 
721 		rdma_recv->sgl[0].addr = (uintptr_t)&resources->cmds[i];
722 		rdma_recv->sgl[0].length = sizeof(resources->cmds[i]);
723 		rdma_recv->sgl[0].lkey = resources->cmds_mr->lkey;
724 		rdma_recv->wr.num_sge = 1;
725 
726 		if (rdma_recv->buf && resources->bufs_mr) {
727 			rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
728 			rdma_recv->sgl[1].length = opts->in_capsule_data_size;
729 			rdma_recv->sgl[1].lkey = resources->bufs_mr->lkey;
730 			rdma_recv->wr.num_sge++;
731 		}
732 
733 		rdma_recv->wr.wr_id = (uintptr_t)&rdma_recv->rdma_wr;
734 		rdma_recv->wr.sg_list = rdma_recv->sgl;
735 		if (opts->shared) {
736 			srq = (struct ibv_srq *)opts->qp;
737 			rc = ibv_post_srq_recv(srq, &rdma_recv->wr, &bad_wr);
738 		} else {
739 			qp = (struct ibv_qp *)opts->qp;
740 			rc = ibv_post_recv(qp, &rdma_recv->wr, &bad_wr);
741 		}
742 		if (rc) {
743 			goto cleanup;
744 		}
745 	}
746 
747 	for (i = 0; i < opts->max_queue_depth; i++) {
748 		rdma_req = &resources->reqs[i];
749 
750 		if (opts->qpair != NULL) {
751 			rdma_req->req.qpair = &opts->qpair->qpair;
752 		} else {
753 			rdma_req->req.qpair = NULL;
754 		}
755 		rdma_req->req.cmd = NULL;
756 
757 		/* Set up memory to send responses */
758 		rdma_req->req.rsp = &resources->cpls[i];
759 
760 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&resources->cpls[i];
761 		rdma_req->rsp.sgl[0].length = sizeof(resources->cpls[i]);
762 		rdma_req->rsp.sgl[0].lkey = resources->cpls_mr->lkey;
763 
764 		rdma_req->rsp.rdma_wr.type = RDMA_WR_TYPE_SEND;
765 		rdma_req->rsp.wr.wr_id = (uintptr_t)&rdma_req->rsp.rdma_wr;
766 		rdma_req->rsp.wr.next = NULL;
767 		rdma_req->rsp.wr.opcode = IBV_WR_SEND;
768 		rdma_req->rsp.wr.send_flags = IBV_SEND_SIGNALED;
769 		rdma_req->rsp.wr.sg_list = rdma_req->rsp.sgl;
770 		rdma_req->rsp.wr.num_sge = SPDK_COUNTOF(rdma_req->rsp.sgl);
771 
772 		/* Set up memory for data buffers */
773 		rdma_req->data.rdma_wr.type = RDMA_WR_TYPE_DATA;
774 		rdma_req->data.wr.wr_id = (uintptr_t)&rdma_req->data.rdma_wr;
775 		rdma_req->data.wr.next = NULL;
776 		rdma_req->data.wr.send_flags = IBV_SEND_SIGNALED;
777 		rdma_req->data.wr.sg_list = rdma_req->data.sgl;
778 		rdma_req->data.wr.num_sge = SPDK_COUNTOF(rdma_req->data.sgl);
779 
780 		/* Initialize request state to FREE */
781 		rdma_req->state = RDMA_REQUEST_STATE_FREE;
782 		STAILQ_INSERT_TAIL(&resources->free_queue, rdma_req, state_link);
783 	}
784 
785 	return resources;
786 
787 cleanup:
788 	nvmf_rdma_resources_destroy(resources);
789 	return NULL;
790 }
791 
792 static void
793 spdk_nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
794 {
795 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
796 	struct ibv_recv_wr		*bad_recv_wr = NULL;
797 	int				rc;
798 
799 	spdk_trace_record(TRACE_RDMA_QP_DESTROY, 0, 0, (uintptr_t)rqpair->cm_id, 0);
800 
801 	spdk_poller_unregister(&rqpair->destruct_poller);
802 
803 	if (rqpair->qd != 0) {
804 		if (rqpair->srq == NULL) {
805 			nvmf_rdma_dump_qpair_contents(rqpair);
806 		}
807 		SPDK_WARNLOG("Destroying qpair when queue depth is %d\n", rqpair->qd);
808 	}
809 
810 	if (rqpair->poller) {
811 		TAILQ_REMOVE(&rqpair->poller->qpairs, rqpair, link);
812 
813 		if (rqpair->srq != NULL) {
814 			/* Drop all received but unprocessed commands for this queue and return them to SRQ */
815 			STAILQ_FOREACH_SAFE(rdma_recv, &rqpair->resources->incoming_queue, link, recv_tmp) {
816 				if (rqpair == rdma_recv->qpair) {
817 					STAILQ_REMOVE_HEAD(&rqpair->resources->incoming_queue, link);
818 					rc = ibv_post_srq_recv(rqpair->srq, &rdma_recv->wr, &bad_recv_wr);
819 					if (rc) {
820 						SPDK_ERRLOG("Unable to re-post rx descriptor\n");
821 					}
822 				}
823 			}
824 		}
825 	}
826 
827 	if (rqpair->cm_id) {
828 		rdma_destroy_qp(rqpair->cm_id);
829 		rdma_destroy_id(rqpair->cm_id);
830 
831 		if (rqpair->poller != NULL && rqpair->srq == NULL) {
832 			rqpair->poller->required_num_wr -= MAX_WR_PER_QP(rqpair->max_queue_depth);
833 		}
834 	}
835 
836 	if (rqpair->srq == NULL) {
837 		nvmf_rdma_resources_destroy(rqpair->resources);
838 	}
839 
840 	free(rqpair);
841 }
842 
843 static int
844 nvmf_rdma_resize_cq(struct spdk_nvmf_rdma_qpair *rqpair, struct spdk_nvmf_rdma_device *device)
845 {
846 	struct spdk_nvmf_rdma_poller	*rpoller;
847 	int				rc, num_cqe, required_num_wr;
848 
849 	/* Enlarge CQ size dynamically */
850 	rpoller = rqpair->poller;
851 	required_num_wr = rpoller->required_num_wr + MAX_WR_PER_QP(rqpair->max_queue_depth);
852 	num_cqe = rpoller->num_cqe;
853 	if (num_cqe < required_num_wr) {
854 		num_cqe = spdk_max(num_cqe * 2, required_num_wr);
855 		num_cqe = spdk_min(num_cqe, device->attr.max_cqe);
856 	}
857 
858 	if (rpoller->num_cqe != num_cqe) {
859 		if (required_num_wr > device->attr.max_cqe) {
860 			SPDK_ERRLOG("RDMA CQE requirement (%d) exceeds device max_cqe limitation (%d)\n",
861 				    required_num_wr, device->attr.max_cqe);
862 			return -1;
863 		}
864 
865 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Resize RDMA CQ from %d to %d\n", rpoller->num_cqe, num_cqe);
866 		rc = ibv_resize_cq(rpoller->cq, num_cqe);
867 		if (rc) {
868 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
869 			return -1;
870 		}
871 
872 		rpoller->num_cqe = num_cqe;
873 	}
874 
875 	rpoller->required_num_wr = required_num_wr;
876 	return 0;
877 }
878 
879 static int
880 spdk_nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
881 {
882 	struct spdk_nvmf_rdma_qpair		*rqpair;
883 	int					rc;
884 	struct spdk_nvmf_rdma_transport		*rtransport;
885 	struct spdk_nvmf_transport		*transport;
886 	struct spdk_nvmf_rdma_resource_opts	opts;
887 	struct spdk_nvmf_rdma_device		*device;
888 	struct ibv_qp_init_attr			ibv_init_attr;
889 
890 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
891 	device = rqpair->port->device;
892 
893 	memset(&ibv_init_attr, 0, sizeof(struct ibv_qp_init_attr));
894 	ibv_init_attr.qp_context	= rqpair;
895 	ibv_init_attr.qp_type		= IBV_QPT_RC;
896 	ibv_init_attr.send_cq		= rqpair->poller->cq;
897 	ibv_init_attr.recv_cq		= rqpair->poller->cq;
898 
899 	if (rqpair->srq) {
900 		ibv_init_attr.srq		= rqpair->srq;
901 	} else {
902 		ibv_init_attr.cap.max_recv_wr	= rqpair->max_queue_depth +
903 						  1; /* RECV operations + dummy drain WR */
904 	}
905 
906 	ibv_init_attr.cap.max_send_wr	= rqpair->max_queue_depth *
907 					  2 + 1; /* SEND, READ, and WRITE operations + dummy drain WR */
908 	ibv_init_attr.cap.max_send_sge	= spdk_min(device->attr.max_sge, NVMF_DEFAULT_TX_SGE);
909 	ibv_init_attr.cap.max_recv_sge	= spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
910 
911 	if (rqpair->srq == NULL && nvmf_rdma_resize_cq(rqpair, device) < 0) {
912 		SPDK_ERRLOG("Failed to resize the completion queue. Cannot initialize qpair.\n");
913 		goto error;
914 	}
915 
916 	rc = rdma_create_qp(rqpair->cm_id, rqpair->port->device->pd, &ibv_init_attr);
917 	if (rc) {
918 		SPDK_ERRLOG("rdma_create_qp failed: errno %d: %s\n", errno, spdk_strerror(errno));
919 		goto error;
920 	}
921 
922 	rqpair->max_send_depth = spdk_min((uint32_t)(rqpair->max_queue_depth * 2 + 1),
923 					  ibv_init_attr.cap.max_send_wr);
924 	rqpair->max_send_sge = spdk_min(NVMF_DEFAULT_TX_SGE, ibv_init_attr.cap.max_send_sge);
925 	rqpair->max_recv_sge = spdk_min(NVMF_DEFAULT_RX_SGE, ibv_init_attr.cap.max_recv_sge);
926 	spdk_trace_record(TRACE_RDMA_QP_CREATE, 0, 0, (uintptr_t)rqpair->cm_id, 0);
927 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "New RDMA Connection: %p\n", qpair);
928 
929 	if (rqpair->poller->srq == NULL) {
930 		rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
931 		transport = &rtransport->transport;
932 
933 		opts.qp = rqpair->cm_id->qp;
934 		opts.pd = rqpair->cm_id->pd;
935 		opts.qpair = rqpair;
936 		opts.shared = false;
937 		opts.max_queue_depth = rqpair->max_queue_depth;
938 		opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
939 
940 		rqpair->resources = nvmf_rdma_resources_create(&opts);
941 
942 		if (!rqpair->resources) {
943 			SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
944 			goto error;
945 		}
946 	} else {
947 		rqpair->resources = rqpair->poller->resources;
948 	}
949 
950 	rqpair->current_recv_depth = 0;
951 	STAILQ_INIT(&rqpair->pending_rdma_read_queue);
952 	STAILQ_INIT(&rqpair->pending_rdma_write_queue);
953 
954 	return 0;
955 
956 error:
957 	rdma_destroy_id(rqpair->cm_id);
958 	rqpair->cm_id = NULL;
959 	spdk_nvmf_rdma_qpair_destroy(rqpair);
960 	return -1;
961 }
962 
963 static int
964 request_transfer_in(struct spdk_nvmf_request *req)
965 {
966 	int				rc;
967 	struct spdk_nvmf_rdma_request	*rdma_req;
968 	struct spdk_nvmf_qpair		*qpair;
969 	struct spdk_nvmf_rdma_qpair	*rqpair;
970 	struct ibv_send_wr		*bad_wr = NULL;
971 
972 	qpair = req->qpair;
973 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
974 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
975 
976 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
977 	assert(rdma_req != NULL);
978 
979 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA READ POSTED. Request: %p Connection: %p\n", req, qpair);
980 
981 	rc = ibv_post_send(rqpair->cm_id->qp, &rdma_req->data.wr, &bad_wr);
982 	if (rc) {
983 		SPDK_ERRLOG("Unable to transfer data from host to target\n");
984 		return -1;
985 	}
986 	rqpair->current_read_depth += rdma_req->num_outstanding_data_wr;
987 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr;
988 	return 0;
989 }
990 
991 static int
992 request_transfer_out(struct spdk_nvmf_request *req, int *data_posted)
993 {
994 	int				rc;
995 	struct spdk_nvmf_rdma_request	*rdma_req;
996 	struct spdk_nvmf_qpair		*qpair;
997 	struct spdk_nvmf_rdma_qpair	*rqpair;
998 	struct spdk_nvme_cpl		*rsp;
999 	struct ibv_recv_wr		*bad_recv_wr = NULL;
1000 	struct ibv_send_wr		*send_wr, *bad_send_wr = NULL;
1001 
1002 	*data_posted = 0;
1003 	qpair = req->qpair;
1004 	rsp = &req->rsp->nvme_cpl;
1005 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1006 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1007 
1008 	/* Advance our sq_head pointer */
1009 	if (qpair->sq_head == qpair->sq_head_max) {
1010 		qpair->sq_head = 0;
1011 	} else {
1012 		qpair->sq_head++;
1013 	}
1014 	rsp->sqhd = qpair->sq_head;
1015 
1016 	/* Post the capsule to the recv buffer */
1017 	assert(rdma_req->recv != NULL);
1018 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA RECV POSTED. Recv: %p Connection: %p\n", rdma_req->recv,
1019 		      rqpair);
1020 	if (rqpair->srq == NULL) {
1021 		rc = ibv_post_recv(rqpair->cm_id->qp, &rdma_req->recv->wr, &bad_recv_wr);
1022 	} else {
1023 		rdma_req->recv->qpair = NULL;
1024 		rc = ibv_post_srq_recv(rqpair->srq, &rdma_req->recv->wr, &bad_recv_wr);
1025 	}
1026 
1027 	if (rc) {
1028 		SPDK_ERRLOG("Unable to re-post rx descriptor\n");
1029 		return rc;
1030 	}
1031 	rdma_req->recv = NULL;
1032 	assert(rqpair->current_recv_depth > 0);
1033 	rqpair->current_recv_depth--;
1034 
1035 	/* Build the response which consists of an optional
1036 	 * RDMA WRITE to transfer data, plus an RDMA SEND
1037 	 * containing the response.
1038 	 */
1039 	send_wr = &rdma_req->rsp.wr;
1040 
1041 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
1042 	    req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1043 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA WRITE POSTED. Request: %p Connection: %p\n", req, qpair);
1044 		send_wr = &rdma_req->data.wr;
1045 		*data_posted = 1;
1046 	}
1047 
1048 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA SEND POSTED. Request: %p Connection: %p\n", req, qpair);
1049 
1050 	/* Send the completion */
1051 	rc = ibv_post_send(rqpair->cm_id->qp, send_wr, &bad_send_wr);
1052 	if (rc) {
1053 		SPDK_ERRLOG("Unable to send response capsule\n");
1054 		return rc;
1055 	}
1056 	/* +1 for the rsp wr */
1057 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr + 1;
1058 
1059 	return 0;
1060 }
1061 
1062 static int
1063 spdk_nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
1064 {
1065 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
1066 	struct rdma_conn_param				ctrlr_event_data = {};
1067 	int						rc;
1068 
1069 	accept_data.recfmt = 0;
1070 	accept_data.crqsize = rqpair->max_queue_depth;
1071 
1072 	ctrlr_event_data.private_data = &accept_data;
1073 	ctrlr_event_data.private_data_len = sizeof(accept_data);
1074 	if (id->ps == RDMA_PS_TCP) {
1075 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
1076 		ctrlr_event_data.initiator_depth = rqpair->max_read_depth;
1077 	}
1078 
1079 	rc = rdma_accept(id, &ctrlr_event_data);
1080 	if (rc) {
1081 		SPDK_ERRLOG("Error %d on rdma_accept\n", errno);
1082 	} else {
1083 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Sent back the accept\n");
1084 	}
1085 
1086 	return rc;
1087 }
1088 
1089 static void
1090 spdk_nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
1091 {
1092 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
1093 
1094 	rej_data.recfmt = 0;
1095 	rej_data.sts = error;
1096 
1097 	rdma_reject(id, &rej_data, sizeof(rej_data));
1098 }
1099 
1100 static int
1101 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event,
1102 		  new_qpair_fn cb_fn)
1103 {
1104 	struct spdk_nvmf_rdma_transport *rtransport;
1105 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
1106 	struct spdk_nvmf_rdma_port	*port;
1107 	struct rdma_conn_param		*rdma_param = NULL;
1108 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
1109 	uint16_t			max_queue_depth;
1110 	uint16_t			max_read_depth;
1111 
1112 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1113 
1114 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
1115 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
1116 
1117 	rdma_param = &event->param.conn;
1118 	if (rdma_param->private_data == NULL ||
1119 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1120 		SPDK_ERRLOG("connect request: no private data provided\n");
1121 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
1122 		return -1;
1123 	}
1124 
1125 	private_data = rdma_param->private_data;
1126 	if (private_data->recfmt != 0) {
1127 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
1128 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
1129 		return -1;
1130 	}
1131 
1132 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Connect Recv on fabric intf name %s, dev_name %s\n",
1133 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
1134 
1135 	port = event->listen_id->context;
1136 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
1137 		      event->listen_id, event->listen_id->verbs, port);
1138 
1139 	/* Figure out the supported queue depth. This is a multi-step process
1140 	 * that takes into account hardware maximums, host provided values,
1141 	 * and our target's internal memory limits */
1142 
1143 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Calculating Queue Depth\n");
1144 
1145 	/* Start with the maximum queue depth allowed by the target */
1146 	max_queue_depth = rtransport->transport.opts.max_queue_depth;
1147 	max_read_depth = rtransport->transport.opts.max_queue_depth;
1148 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Target Max Queue Depth: %d\n",
1149 		      rtransport->transport.opts.max_queue_depth);
1150 
1151 	/* Next check the local NIC's hardware limitations */
1152 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
1153 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
1154 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
1155 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
1156 	max_read_depth = spdk_min(max_read_depth, port->device->attr.max_qp_init_rd_atom);
1157 
1158 	/* Next check the remote NIC's hardware limitations */
1159 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
1160 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
1161 		      rdma_param->initiator_depth, rdma_param->responder_resources);
1162 	if (rdma_param->initiator_depth > 0) {
1163 		max_read_depth = spdk_min(max_read_depth, rdma_param->initiator_depth);
1164 	}
1165 
1166 	/* Finally check for the host software requested values, which are
1167 	 * optional. */
1168 	if (rdma_param->private_data != NULL &&
1169 	    rdma_param->private_data_len >= sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1170 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1171 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Send Queue Size: %d\n", private_data->hsqsize);
1172 		max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
1173 		max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
1174 	}
1175 
1176 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
1177 		      max_queue_depth, max_read_depth);
1178 
1179 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
1180 	if (rqpair == NULL) {
1181 		SPDK_ERRLOG("Could not allocate new connection.\n");
1182 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1183 		return -1;
1184 	}
1185 
1186 	rqpair->port = port;
1187 	rqpair->max_queue_depth = max_queue_depth;
1188 	rqpair->max_read_depth = max_read_depth;
1189 	rqpair->cm_id = event->id;
1190 	rqpair->listen_id = event->listen_id;
1191 	rqpair->qpair.transport = transport;
1192 
1193 	event->id->context = &rqpair->qpair;
1194 
1195 	cb_fn(&rqpair->qpair);
1196 
1197 	return 0;
1198 }
1199 
1200 static int
1201 spdk_nvmf_rdma_mem_notify(void *cb_ctx, struct spdk_mem_map *map,
1202 			  enum spdk_mem_map_notify_action action,
1203 			  void *vaddr, size_t size)
1204 {
1205 	struct ibv_pd *pd = cb_ctx;
1206 	struct ibv_mr *mr;
1207 
1208 	switch (action) {
1209 	case SPDK_MEM_MAP_NOTIFY_REGISTER:
1210 		if (!g_nvmf_hooks.get_rkey) {
1211 			mr = ibv_reg_mr(pd, vaddr, size,
1212 					IBV_ACCESS_LOCAL_WRITE |
1213 					IBV_ACCESS_REMOTE_READ |
1214 					IBV_ACCESS_REMOTE_WRITE);
1215 			if (mr == NULL) {
1216 				SPDK_ERRLOG("ibv_reg_mr() failed\n");
1217 				return -1;
1218 			} else {
1219 				spdk_mem_map_set_translation(map, (uint64_t)vaddr, size, (uint64_t)mr);
1220 			}
1221 		} else {
1222 			spdk_mem_map_set_translation(map, (uint64_t)vaddr, size,
1223 						     g_nvmf_hooks.get_rkey(pd, vaddr, size));
1224 		}
1225 		break;
1226 	case SPDK_MEM_MAP_NOTIFY_UNREGISTER:
1227 		if (!g_nvmf_hooks.get_rkey) {
1228 			mr = (struct ibv_mr *)spdk_mem_map_translate(map, (uint64_t)vaddr, NULL);
1229 			spdk_mem_map_clear_translation(map, (uint64_t)vaddr, size);
1230 			if (mr) {
1231 				ibv_dereg_mr(mr);
1232 			}
1233 		}
1234 		break;
1235 	}
1236 
1237 	return 0;
1238 }
1239 
1240 static int
1241 spdk_nvmf_rdma_check_contiguous_entries(uint64_t addr_1, uint64_t addr_2)
1242 {
1243 	/* Two contiguous mappings will point to the same address which is the start of the RDMA MR. */
1244 	return addr_1 == addr_2;
1245 }
1246 
1247 static void
1248 spdk_nvmf_rdma_request_free_buffers(struct spdk_nvmf_rdma_request *rdma_req,
1249 				    struct spdk_nvmf_transport_poll_group *group, struct spdk_nvmf_transport *transport)
1250 {
1251 	for (uint32_t i = 0; i < rdma_req->req.iovcnt; i++) {
1252 		if (group->buf_cache_count < group->buf_cache_size) {
1253 			STAILQ_INSERT_HEAD(&group->buf_cache,
1254 					   (struct spdk_nvmf_transport_pg_cache_buf *)rdma_req->data.buffers[i], link);
1255 			group->buf_cache_count++;
1256 		} else {
1257 			spdk_mempool_put(transport->data_buf_pool, rdma_req->data.buffers[i]);
1258 		}
1259 		rdma_req->req.iov[i].iov_base = NULL;
1260 		rdma_req->data.buffers[i] = NULL;
1261 		rdma_req->req.iov[i].iov_len = 0;
1262 
1263 	}
1264 	rdma_req->data_from_pool = false;
1265 }
1266 
1267 typedef enum spdk_nvme_data_transfer spdk_nvme_data_transfer_t;
1268 
1269 static spdk_nvme_data_transfer_t
1270 spdk_nvmf_rdma_request_get_xfer(struct spdk_nvmf_rdma_request *rdma_req)
1271 {
1272 	enum spdk_nvme_data_transfer xfer;
1273 	struct spdk_nvme_cmd *cmd = &rdma_req->req.cmd->nvme_cmd;
1274 	struct spdk_nvme_sgl_descriptor *sgl = &cmd->dptr.sgl1;
1275 
1276 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1277 	rdma_req->rsp.wr.opcode = IBV_WR_SEND;
1278 	rdma_req->rsp.wr.imm_data = 0;
1279 #endif
1280 
1281 	/* Figure out data transfer direction */
1282 	if (cmd->opc == SPDK_NVME_OPC_FABRIC) {
1283 		xfer = spdk_nvme_opc_get_data_transfer(rdma_req->req.cmd->nvmf_cmd.fctype);
1284 	} else {
1285 		xfer = spdk_nvme_opc_get_data_transfer(cmd->opc);
1286 
1287 		/* Some admin commands are special cases */
1288 		if ((rdma_req->req.qpair->qid == 0) &&
1289 		    ((cmd->opc == SPDK_NVME_OPC_GET_FEATURES) ||
1290 		     (cmd->opc == SPDK_NVME_OPC_SET_FEATURES))) {
1291 			switch (cmd->cdw10 & 0xff) {
1292 			case SPDK_NVME_FEAT_LBA_RANGE_TYPE:
1293 			case SPDK_NVME_FEAT_AUTONOMOUS_POWER_STATE_TRANSITION:
1294 			case SPDK_NVME_FEAT_HOST_IDENTIFIER:
1295 				break;
1296 			default:
1297 				xfer = SPDK_NVME_DATA_NONE;
1298 			}
1299 		}
1300 	}
1301 
1302 	if (xfer == SPDK_NVME_DATA_NONE) {
1303 		return xfer;
1304 	}
1305 
1306 	/* Even for commands that may transfer data, they could have specified 0 length.
1307 	 * We want those to show up with xfer SPDK_NVME_DATA_NONE.
1308 	 */
1309 	switch (sgl->generic.type) {
1310 	case SPDK_NVME_SGL_TYPE_DATA_BLOCK:
1311 	case SPDK_NVME_SGL_TYPE_BIT_BUCKET:
1312 	case SPDK_NVME_SGL_TYPE_SEGMENT:
1313 	case SPDK_NVME_SGL_TYPE_LAST_SEGMENT:
1314 	case SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK:
1315 		if (sgl->unkeyed.length == 0) {
1316 			xfer = SPDK_NVME_DATA_NONE;
1317 		}
1318 		break;
1319 	case SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK:
1320 		if (sgl->keyed.length == 0) {
1321 			xfer = SPDK_NVME_DATA_NONE;
1322 		}
1323 		break;
1324 	}
1325 
1326 	return xfer;
1327 }
1328 
1329 static int
1330 nvmf_rdma_fill_buffers(struct spdk_nvmf_rdma_transport *rtransport,
1331 		       struct spdk_nvmf_rdma_poll_group *rgroup,
1332 		       struct spdk_nvmf_rdma_device *device,
1333 		       struct spdk_nvmf_rdma_request *rdma_req,
1334 		       struct ibv_send_wr *wr,
1335 		       uint32_t length)
1336 {
1337 	void		*buf = NULL;
1338 	uint64_t	translation_len;
1339 	uint32_t	remaining_length = length;
1340 	uint32_t	iovcnt;
1341 	uint32_t	i = 0;
1342 
1343 
1344 	while (remaining_length) {
1345 		if (!(STAILQ_EMPTY(&rgroup->group.buf_cache))) {
1346 			rgroup->group.buf_cache_count--;
1347 			buf = STAILQ_FIRST(&rgroup->group.buf_cache);
1348 			STAILQ_REMOVE_HEAD(&rgroup->group.buf_cache, link);
1349 			assert(buf != NULL);
1350 		} else {
1351 			buf = spdk_mempool_get(rtransport->transport.data_buf_pool);
1352 			if (!buf) {
1353 				return -ENOMEM;
1354 			}
1355 		}
1356 
1357 		iovcnt = rdma_req->req.iovcnt;
1358 		rdma_req->req.iov[iovcnt].iov_base = (void *)((uintptr_t)(buf + NVMF_DATA_BUFFER_MASK) &
1359 						     ~NVMF_DATA_BUFFER_MASK);
1360 		rdma_req->req.iov[iovcnt].iov_len  = spdk_min(remaining_length,
1361 						     rtransport->transport.opts.io_unit_size);
1362 		rdma_req->req.iovcnt++;
1363 		rdma_req->data.buffers[iovcnt] = buf;
1364 		wr->sg_list[i].addr = (uintptr_t)(rdma_req->req.iov[iovcnt].iov_base);
1365 		wr->sg_list[i].length = rdma_req->req.iov[iovcnt].iov_len;
1366 		translation_len = rdma_req->req.iov[iovcnt].iov_len;
1367 
1368 		if (!g_nvmf_hooks.get_rkey) {
1369 			wr->sg_list[i].lkey = ((struct ibv_mr *)spdk_mem_map_translate(device->map,
1370 					       (uint64_t)buf, &translation_len))->lkey;
1371 		} else {
1372 			wr->sg_list[i].lkey = spdk_mem_map_translate(device->map,
1373 					      (uint64_t)buf, &translation_len);
1374 		}
1375 
1376 		remaining_length -= rdma_req->req.iov[iovcnt].iov_len;
1377 
1378 		if (translation_len < rdma_req->req.iov[iovcnt].iov_len) {
1379 			SPDK_ERRLOG("Data buffer split over multiple RDMA Memory Regions\n");
1380 			return -EINVAL;
1381 		}
1382 		i++;
1383 	}
1384 
1385 	return 0;
1386 }
1387 
1388 static int
1389 spdk_nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1390 				 struct spdk_nvmf_rdma_device *device,
1391 				 struct spdk_nvmf_rdma_request *rdma_req)
1392 {
1393 	struct spdk_nvmf_rdma_qpair		*rqpair;
1394 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1395 	uint32_t				i = 0;
1396 	int					rc = 0;
1397 
1398 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1399 	rgroup = rqpair->poller->group;
1400 	rdma_req->req.iovcnt = 0;
1401 
1402 	rc = nvmf_rdma_fill_buffers(rtransport, rgroup, device, rdma_req, &rdma_req->data.wr,
1403 				    rdma_req->req.length);
1404 	if (rc != 0) {
1405 		goto err_exit;
1406 	}
1407 
1408 	assert(rdma_req->req.iovcnt <= rqpair->max_send_sge);
1409 
1410 	rdma_req->data_from_pool = true;
1411 
1412 	return rc;
1413 
1414 err_exit:
1415 	spdk_nvmf_rdma_request_free_buffers(rdma_req, &rgroup->group, &rtransport->transport);
1416 	while (i) {
1417 		i--;
1418 		rdma_req->data.wr.sg_list[i].addr = 0;
1419 		rdma_req->data.wr.sg_list[i].length = 0;
1420 		rdma_req->data.wr.sg_list[i].lkey = 0;
1421 	}
1422 	rdma_req->req.iovcnt = 0;
1423 	return rc;
1424 }
1425 
1426 static int
1427 spdk_nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1428 				 struct spdk_nvmf_rdma_device *device,
1429 				 struct spdk_nvmf_rdma_request *rdma_req)
1430 {
1431 	struct spdk_nvme_cmd			*cmd;
1432 	struct spdk_nvme_cpl			*rsp;
1433 	struct spdk_nvme_sgl_descriptor		*sgl;
1434 
1435 	cmd = &rdma_req->req.cmd->nvme_cmd;
1436 	rsp = &rdma_req->req.rsp->nvme_cpl;
1437 	sgl = &cmd->dptr.sgl1;
1438 
1439 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1440 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1441 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1442 		if (sgl->keyed.length > rtransport->transport.opts.max_io_size) {
1443 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1444 				    sgl->keyed.length, rtransport->transport.opts.max_io_size);
1445 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1446 			return -1;
1447 		}
1448 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1449 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1450 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1451 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1452 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1453 			}
1454 		}
1455 #endif
1456 
1457 		/* fill request length and populate iovs */
1458 		rdma_req->req.length = sgl->keyed.length;
1459 
1460 		if (spdk_nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req) < 0) {
1461 			/* No available buffers. Queue this request up. */
1462 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1463 			return 0;
1464 		}
1465 
1466 		/* backward compatible */
1467 		rdma_req->req.data = rdma_req->req.iov[0].iov_base;
1468 
1469 		/* rdma wr specifics */
1470 		rdma_req->data.wr.num_sge = rdma_req->req.iovcnt;
1471 		rdma_req->data.wr.wr.rdma.rkey = sgl->keyed.key;
1472 		rdma_req->data.wr.wr.rdma.remote_addr = sgl->address;
1473 		if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1474 			rdma_req->data.wr.opcode = IBV_WR_RDMA_WRITE;
1475 			rdma_req->data.wr.next = &rdma_req->rsp.wr;
1476 		} else if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1477 			rdma_req->data.wr.opcode = IBV_WR_RDMA_READ;
1478 			rdma_req->data.wr.next = NULL;
1479 		}
1480 
1481 		/* set the number of outstanding data WRs for this request. */
1482 		rdma_req->num_outstanding_data_wr = 1;
1483 
1484 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1485 			      rdma_req->req.iovcnt);
1486 
1487 		return 0;
1488 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1489 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1490 		uint64_t offset = sgl->address;
1491 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1492 
1493 		SPDK_DEBUGLOG(SPDK_LOG_NVMF, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1494 			      offset, sgl->unkeyed.length);
1495 
1496 		if (offset > max_len) {
1497 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1498 				    offset, max_len);
1499 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1500 			return -1;
1501 		}
1502 		max_len -= (uint32_t)offset;
1503 
1504 		if (sgl->unkeyed.length > max_len) {
1505 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1506 				    sgl->unkeyed.length, max_len);
1507 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1508 			return -1;
1509 		}
1510 
1511 		rdma_req->num_outstanding_data_wr = 0;
1512 		rdma_req->req.data = rdma_req->recv->buf + offset;
1513 		rdma_req->data_from_pool = false;
1514 		rdma_req->req.length = sgl->unkeyed.length;
1515 
1516 		rdma_req->req.iov[0].iov_base = rdma_req->req.data;
1517 		rdma_req->req.iov[0].iov_len = rdma_req->req.length;
1518 		rdma_req->req.iovcnt = 1;
1519 
1520 		return 0;
1521 	}
1522 
1523 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1524 		    sgl->generic.type, sgl->generic.subtype);
1525 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1526 	return -1;
1527 }
1528 
1529 static void
1530 nvmf_rdma_request_free(struct spdk_nvmf_rdma_request *rdma_req,
1531 		       struct spdk_nvmf_rdma_transport	*rtransport)
1532 {
1533 	struct spdk_nvmf_rdma_qpair		*rqpair;
1534 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1535 
1536 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1537 	if (rdma_req->data_from_pool) {
1538 		rgroup = rqpair->poller->group;
1539 
1540 		spdk_nvmf_rdma_request_free_buffers(rdma_req, &rgroup->group, &rtransport->transport);
1541 	}
1542 	rdma_req->num_outstanding_data_wr = 0;
1543 	rdma_req->req.length = 0;
1544 	rdma_req->req.iovcnt = 0;
1545 	rdma_req->req.data = NULL;
1546 	rqpair->qd--;
1547 
1548 	STAILQ_INSERT_HEAD(&rqpair->resources->free_queue, rdma_req, state_link);
1549 	rdma_req->state = RDMA_REQUEST_STATE_FREE;
1550 }
1551 
1552 static bool
1553 spdk_nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
1554 			       struct spdk_nvmf_rdma_request *rdma_req)
1555 {
1556 	struct spdk_nvmf_rdma_qpair	*rqpair;
1557 	struct spdk_nvmf_rdma_device	*device;
1558 	struct spdk_nvmf_rdma_poll_group *rgroup;
1559 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
1560 	int				rc;
1561 	struct spdk_nvmf_rdma_recv	*rdma_recv;
1562 	enum spdk_nvmf_rdma_request_state prev_state;
1563 	bool				progress = false;
1564 	int				data_posted;
1565 
1566 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1567 	device = rqpair->port->device;
1568 	rgroup = rqpair->poller->group;
1569 
1570 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
1571 
1572 	/* If the queue pair is in an error state, force the request to the completed state
1573 	 * to release resources. */
1574 	if (rqpair->ibv_attr.qp_state == IBV_QPS_ERR || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1575 		if (rdma_req->state == RDMA_REQUEST_STATE_NEED_BUFFER) {
1576 			TAILQ_REMOVE(&rgroup->pending_data_buf_queue, rdma_req, link);
1577 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING) {
1578 			STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1579 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING) {
1580 			STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
1581 		}
1582 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1583 	}
1584 
1585 	/* The loop here is to allow for several back-to-back state changes. */
1586 	do {
1587 		prev_state = rdma_req->state;
1588 
1589 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p entering state %d\n", rdma_req, prev_state);
1590 
1591 		switch (rdma_req->state) {
1592 		case RDMA_REQUEST_STATE_FREE:
1593 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
1594 			 * to escape this state. */
1595 			break;
1596 		case RDMA_REQUEST_STATE_NEW:
1597 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
1598 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1599 			rdma_recv = rdma_req->recv;
1600 
1601 			/* The first element of the SGL is the NVMe command */
1602 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
1603 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
1604 
1605 			if (rqpair->ibv_attr.qp_state == IBV_QPS_ERR  || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1606 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1607 				break;
1608 			}
1609 
1610 			/* The next state transition depends on the data transfer needs of this request. */
1611 			rdma_req->req.xfer = spdk_nvmf_rdma_request_get_xfer(rdma_req);
1612 
1613 			/* If no data to transfer, ready to execute. */
1614 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
1615 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1616 				break;
1617 			}
1618 
1619 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
1620 			TAILQ_INSERT_TAIL(&rgroup->pending_data_buf_queue, rdma_req, link);
1621 			break;
1622 		case RDMA_REQUEST_STATE_NEED_BUFFER:
1623 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
1624 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1625 
1626 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
1627 
1628 			if (rdma_req != TAILQ_FIRST(&rgroup->pending_data_buf_queue)) {
1629 				/* This request needs to wait in line to obtain a buffer */
1630 				break;
1631 			}
1632 
1633 			/* Try to get a data buffer */
1634 			rc = spdk_nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
1635 			if (rc < 0) {
1636 				TAILQ_REMOVE(&rgroup->pending_data_buf_queue, rdma_req, link);
1637 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
1638 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1639 				break;
1640 			}
1641 
1642 			if (!rdma_req->req.data) {
1643 				/* No buffers available. */
1644 				break;
1645 			}
1646 
1647 			TAILQ_REMOVE(&rgroup->pending_data_buf_queue, rdma_req, link);
1648 
1649 			/* If data is transferring from host to controller and the data didn't
1650 			 * arrive using in capsule data, we need to do a transfer from the host.
1651 			 */
1652 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER && rdma_req->data_from_pool) {
1653 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
1654 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
1655 				break;
1656 			}
1657 
1658 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1659 			break;
1660 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
1661 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING, 0, 0,
1662 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1663 
1664 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_read_queue)) {
1665 				/* This request needs to wait in line to perform RDMA */
1666 				break;
1667 			}
1668 			if (rqpair->current_send_depth + rdma_req->num_outstanding_data_wr > rqpair->max_send_depth
1669 			    || rqpair->current_read_depth + rdma_req->num_outstanding_data_wr > rqpair->max_read_depth) {
1670 				/* We can only have so many WRs outstanding. we have to wait until some finish. */
1671 				break;
1672 			}
1673 
1674 			/* We have already verified that this request is the head of the queue. */
1675 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_read_queue, state_link);
1676 
1677 			rc = request_transfer_in(&rdma_req->req);
1678 			if (!rc) {
1679 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
1680 			} else {
1681 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
1682 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1683 			}
1684 			break;
1685 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
1686 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
1687 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1688 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
1689 			 * to escape this state. */
1690 			break;
1691 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
1692 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
1693 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1694 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
1695 			spdk_nvmf_request_exec(&rdma_req->req);
1696 			break;
1697 		case RDMA_REQUEST_STATE_EXECUTING:
1698 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
1699 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1700 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
1701 			 * to escape this state. */
1702 			break;
1703 		case RDMA_REQUEST_STATE_EXECUTED:
1704 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
1705 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1706 			if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1707 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_write_queue, rdma_req, state_link);
1708 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING;
1709 			} else {
1710 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1711 			}
1712 			break;
1713 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
1714 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING, 0, 0,
1715 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1716 
1717 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_write_queue)) {
1718 				/* This request needs to wait in line to perform RDMA */
1719 				break;
1720 			}
1721 			if ((rqpair->current_send_depth + rdma_req->num_outstanding_data_wr + 1) >
1722 			    rqpair->max_send_depth) {
1723 				/* We can only have so many WRs outstanding. we have to wait until some finish.
1724 				 * +1 since each request has an additional wr in the resp. */
1725 				break;
1726 			}
1727 
1728 			/* We have already verified that this request is the head of the queue. */
1729 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_write_queue, state_link);
1730 
1731 			/* The data transfer will be kicked off from
1732 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
1733 			 */
1734 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1735 			break;
1736 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
1737 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
1738 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1739 			rc = request_transfer_out(&rdma_req->req, &data_posted);
1740 			assert(rc == 0); /* No good way to handle this currently */
1741 			if (rc) {
1742 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1743 			} else {
1744 				rdma_req->state = data_posted ? RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
1745 						  RDMA_REQUEST_STATE_COMPLETING;
1746 			}
1747 			break;
1748 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
1749 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
1750 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1751 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
1752 			 * to escape this state. */
1753 			break;
1754 		case RDMA_REQUEST_STATE_COMPLETING:
1755 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
1756 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1757 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
1758 			 * to escape this state. */
1759 			break;
1760 		case RDMA_REQUEST_STATE_COMPLETED:
1761 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
1762 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1763 
1764 			nvmf_rdma_request_free(rdma_req, rtransport);
1765 			break;
1766 		case RDMA_REQUEST_NUM_STATES:
1767 		default:
1768 			assert(0);
1769 			break;
1770 		}
1771 
1772 		if (rdma_req->state != prev_state) {
1773 			progress = true;
1774 		}
1775 	} while (rdma_req->state != prev_state);
1776 
1777 	return progress;
1778 }
1779 
1780 /* Public API callbacks begin here */
1781 
1782 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
1783 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
1784 #define SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH 4096
1785 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 64
1786 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
1787 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
1788 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
1789 #define SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS 4096
1790 #define SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE 32
1791 
1792 static void
1793 spdk_nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
1794 {
1795 	opts->max_queue_depth =		SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
1796 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
1797 	opts->in_capsule_data_size =	SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
1798 	opts->max_io_size =		SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
1799 	opts->io_unit_size =		SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE;
1800 	opts->max_aq_depth =		SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
1801 	opts->num_shared_buffers =	SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS;
1802 	opts->buf_cache_size =		SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE;
1803 	opts->max_srq_depth =		SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH;
1804 }
1805 
1806 const struct spdk_mem_map_ops g_nvmf_rdma_map_ops = {
1807 	.notify_cb = spdk_nvmf_rdma_mem_notify,
1808 	.are_contiguous = spdk_nvmf_rdma_check_contiguous_entries
1809 };
1810 
1811 static int spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport);
1812 
1813 static struct spdk_nvmf_transport *
1814 spdk_nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
1815 {
1816 	int rc;
1817 	struct spdk_nvmf_rdma_transport *rtransport;
1818 	struct spdk_nvmf_rdma_device	*device, *tmp;
1819 	struct ibv_pd			*pd;
1820 	struct ibv_context		**contexts;
1821 	uint32_t			i;
1822 	int				flag;
1823 	uint32_t			sge_count;
1824 	uint32_t			min_shared_buffers;
1825 	int				max_device_sge = SPDK_NVMF_MAX_SGL_ENTRIES;
1826 
1827 	rtransport = calloc(1, sizeof(*rtransport));
1828 	if (!rtransport) {
1829 		return NULL;
1830 	}
1831 
1832 	if (pthread_mutex_init(&rtransport->lock, NULL)) {
1833 		SPDK_ERRLOG("pthread_mutex_init() failed\n");
1834 		free(rtransport);
1835 		return NULL;
1836 	}
1837 
1838 	TAILQ_INIT(&rtransport->devices);
1839 	TAILQ_INIT(&rtransport->ports);
1840 
1841 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
1842 
1843 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** RDMA Transport Init ***\n"
1844 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
1845 		     "  max_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
1846 		     "  in_capsule_data_size=%d, max_aq_depth=%d,\n"
1847 		     "  num_shared_buffers=%d, max_srq_depth=%d\n",
1848 		     opts->max_queue_depth,
1849 		     opts->max_io_size,
1850 		     opts->max_qpairs_per_ctrlr,
1851 		     opts->io_unit_size,
1852 		     opts->in_capsule_data_size,
1853 		     opts->max_aq_depth,
1854 		     opts->num_shared_buffers,
1855 		     opts->max_srq_depth);
1856 
1857 	/* I/O unit size cannot be larger than max I/O size */
1858 	if (opts->io_unit_size > opts->max_io_size) {
1859 		opts->io_unit_size = opts->max_io_size;
1860 	}
1861 
1862 	if (opts->num_shared_buffers < (SPDK_NVMF_MAX_SGL_ENTRIES * 2)) {
1863 		SPDK_ERRLOG("The number of shared data buffers (%d) is less than"
1864 			    "the minimum number required to guarantee that forward progress can be made (%d)\n",
1865 			    opts->num_shared_buffers, (SPDK_NVMF_MAX_SGL_ENTRIES * 2));
1866 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1867 		return NULL;
1868 	}
1869 
1870 	min_shared_buffers = spdk_thread_get_count() * opts->buf_cache_size;
1871 	if (min_shared_buffers > opts->num_shared_buffers) {
1872 		SPDK_ERRLOG("There are not enough buffers to satisfy"
1873 			    "per-poll group caches for each thread. (%" PRIu32 ")"
1874 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
1875 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
1876 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1877 		return NULL;
1878 	}
1879 
1880 	sge_count = opts->max_io_size / opts->io_unit_size;
1881 	if (sge_count > NVMF_DEFAULT_TX_SGE) {
1882 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
1883 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1884 		return NULL;
1885 	}
1886 
1887 	rtransport->event_channel = rdma_create_event_channel();
1888 	if (rtransport->event_channel == NULL) {
1889 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
1890 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1891 		return NULL;
1892 	}
1893 
1894 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
1895 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
1896 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
1897 			    rtransport->event_channel->fd, spdk_strerror(errno));
1898 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1899 		return NULL;
1900 	}
1901 
1902 	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data",
1903 				   opts->max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES,
1904 				   sizeof(struct spdk_nvmf_rdma_request_data),
1905 				   SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
1906 				   SPDK_ENV_SOCKET_ID_ANY);
1907 	if (!rtransport->data_wr_pool) {
1908 		SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");
1909 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1910 		return NULL;
1911 	}
1912 
1913 	contexts = rdma_get_devices(NULL);
1914 	if (contexts == NULL) {
1915 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
1916 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1917 		return NULL;
1918 	}
1919 
1920 	i = 0;
1921 	rc = 0;
1922 	while (contexts[i] != NULL) {
1923 		device = calloc(1, sizeof(*device));
1924 		if (!device) {
1925 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
1926 			rc = -ENOMEM;
1927 			break;
1928 		}
1929 		device->context = contexts[i];
1930 		rc = ibv_query_device(device->context, &device->attr);
1931 		if (rc < 0) {
1932 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
1933 			free(device);
1934 			break;
1935 
1936 		}
1937 
1938 		max_device_sge = spdk_min(max_device_sge, device->attr.max_sge);
1939 
1940 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1941 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
1942 			SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
1943 			SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
1944 		}
1945 
1946 		/**
1947 		 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
1948 		 * The Soft-RoCE RXE driver does not currently support send with invalidate,
1949 		 * but incorrectly reports that it does. There are changes making their way
1950 		 * through the kernel now that will enable this feature. When they are merged,
1951 		 * we can conditionally enable this feature.
1952 		 *
1953 		 * TODO: enable this for versions of the kernel rxe driver that support it.
1954 		 */
1955 		if (device->attr.vendor_id == 0) {
1956 			device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
1957 		}
1958 #endif
1959 
1960 		/* set up device context async ev fd as NON_BLOCKING */
1961 		flag = fcntl(device->context->async_fd, F_GETFL);
1962 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
1963 		if (rc < 0) {
1964 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
1965 			free(device);
1966 			break;
1967 		}
1968 
1969 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
1970 		i++;
1971 
1972 		pd = NULL;
1973 		if (g_nvmf_hooks.get_ibv_pd) {
1974 			pd = g_nvmf_hooks.get_ibv_pd(NULL, device->context);
1975 		}
1976 
1977 		if (!g_nvmf_hooks.get_ibv_pd) {
1978 			device->pd = ibv_alloc_pd(device->context);
1979 			if (!device->pd) {
1980 				SPDK_ERRLOG("Unable to allocate protection domain.\n");
1981 				spdk_nvmf_rdma_destroy(&rtransport->transport);
1982 				return NULL;
1983 			}
1984 		} else {
1985 			device->pd = pd;
1986 		}
1987 
1988 		assert(device->map == NULL);
1989 
1990 		device->map = spdk_mem_map_alloc(0, &g_nvmf_rdma_map_ops, device->pd);
1991 		if (!device->map) {
1992 			SPDK_ERRLOG("Unable to allocate memory map for listen address\n");
1993 			spdk_nvmf_rdma_destroy(&rtransport->transport);
1994 			return NULL;
1995 		}
1996 
1997 		assert(device->map != NULL);
1998 		assert(device->pd != NULL);
1999 	}
2000 	rdma_free_devices(contexts);
2001 
2002 	if (opts->io_unit_size * max_device_sge < opts->max_io_size) {
2003 		/* divide and round up. */
2004 		opts->io_unit_size = (opts->max_io_size + max_device_sge - 1) / max_device_sge;
2005 
2006 		/* round up to the nearest 4k. */
2007 		opts->io_unit_size = (opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT - 1) & ~NVMF_DATA_BUFFER_MASK;
2008 
2009 		opts->io_unit_size = spdk_max(opts->io_unit_size, SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
2010 		SPDK_NOTICELOG("Adjusting the io unit size to fit the device's maximum I/O size. New I/O unit size %u\n",
2011 			       opts->io_unit_size);
2012 	}
2013 
2014 	if (rc < 0) {
2015 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2016 		return NULL;
2017 	}
2018 
2019 	/* Set up poll descriptor array to monitor events from RDMA and IB
2020 	 * in a single poll syscall
2021 	 */
2022 	rtransport->npoll_fds = i + 1;
2023 	i = 0;
2024 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
2025 	if (rtransport->poll_fds == NULL) {
2026 		SPDK_ERRLOG("poll_fds allocation failed\n");
2027 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2028 		return NULL;
2029 	}
2030 
2031 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
2032 	rtransport->poll_fds[i++].events = POLLIN;
2033 
2034 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2035 		rtransport->poll_fds[i].fd = device->context->async_fd;
2036 		rtransport->poll_fds[i++].events = POLLIN;
2037 	}
2038 
2039 	return &rtransport->transport;
2040 }
2041 
2042 static int
2043 spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport)
2044 {
2045 	struct spdk_nvmf_rdma_transport	*rtransport;
2046 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
2047 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
2048 
2049 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2050 
2051 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
2052 		TAILQ_REMOVE(&rtransport->ports, port, link);
2053 		rdma_destroy_id(port->id);
2054 		free(port);
2055 	}
2056 
2057 	if (rtransport->poll_fds != NULL) {
2058 		free(rtransport->poll_fds);
2059 	}
2060 
2061 	if (rtransport->event_channel != NULL) {
2062 		rdma_destroy_event_channel(rtransport->event_channel);
2063 	}
2064 
2065 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
2066 		TAILQ_REMOVE(&rtransport->devices, device, link);
2067 		if (device->map) {
2068 			spdk_mem_map_free(&device->map);
2069 		}
2070 		if (device->pd) {
2071 			if (!g_nvmf_hooks.get_ibv_pd) {
2072 				ibv_dealloc_pd(device->pd);
2073 			}
2074 		}
2075 		free(device);
2076 	}
2077 
2078 	if (rtransport->data_wr_pool != NULL) {
2079 		if (spdk_mempool_count(rtransport->data_wr_pool) !=
2080 		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {
2081 			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",
2082 				    spdk_mempool_count(rtransport->data_wr_pool),
2083 				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);
2084 		}
2085 	}
2086 
2087 	spdk_mempool_free(rtransport->data_wr_pool);
2088 	pthread_mutex_destroy(&rtransport->lock);
2089 	free(rtransport);
2090 
2091 	return 0;
2092 }
2093 
2094 static int
2095 spdk_nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2096 			       struct spdk_nvme_transport_id *trid,
2097 			       bool peer);
2098 
2099 static int
2100 spdk_nvmf_rdma_listen(struct spdk_nvmf_transport *transport,
2101 		      const struct spdk_nvme_transport_id *trid)
2102 {
2103 	struct spdk_nvmf_rdma_transport	*rtransport;
2104 	struct spdk_nvmf_rdma_device	*device;
2105 	struct spdk_nvmf_rdma_port	*port_tmp, *port;
2106 	struct addrinfo			*res;
2107 	struct addrinfo			hints;
2108 	int				family;
2109 	int				rc;
2110 
2111 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2112 
2113 	port = calloc(1, sizeof(*port));
2114 	if (!port) {
2115 		return -ENOMEM;
2116 	}
2117 
2118 	/* Selectively copy the trid. Things like NQN don't matter here - that
2119 	 * mapping is enforced elsewhere.
2120 	 */
2121 	port->trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
2122 	port->trid.adrfam = trid->adrfam;
2123 	snprintf(port->trid.traddr, sizeof(port->trid.traddr), "%s", trid->traddr);
2124 	snprintf(port->trid.trsvcid, sizeof(port->trid.trsvcid), "%s", trid->trsvcid);
2125 
2126 	pthread_mutex_lock(&rtransport->lock);
2127 	assert(rtransport->event_channel != NULL);
2128 	TAILQ_FOREACH(port_tmp, &rtransport->ports, link) {
2129 		if (spdk_nvme_transport_id_compare(&port_tmp->trid, &port->trid) == 0) {
2130 			port_tmp->ref++;
2131 			free(port);
2132 			/* Already listening at this address */
2133 			pthread_mutex_unlock(&rtransport->lock);
2134 			return 0;
2135 		}
2136 	}
2137 
2138 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
2139 	if (rc < 0) {
2140 		SPDK_ERRLOG("rdma_create_id() failed\n");
2141 		free(port);
2142 		pthread_mutex_unlock(&rtransport->lock);
2143 		return rc;
2144 	}
2145 
2146 	switch (port->trid.adrfam) {
2147 	case SPDK_NVMF_ADRFAM_IPV4:
2148 		family = AF_INET;
2149 		break;
2150 	case SPDK_NVMF_ADRFAM_IPV6:
2151 		family = AF_INET6;
2152 		break;
2153 	default:
2154 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", port->trid.adrfam);
2155 		free(port);
2156 		pthread_mutex_unlock(&rtransport->lock);
2157 		return -EINVAL;
2158 	}
2159 
2160 	memset(&hints, 0, sizeof(hints));
2161 	hints.ai_family = family;
2162 	hints.ai_flags = AI_NUMERICSERV;
2163 	hints.ai_socktype = SOCK_STREAM;
2164 	hints.ai_protocol = 0;
2165 
2166 	rc = getaddrinfo(port->trid.traddr, port->trid.trsvcid, &hints, &res);
2167 	if (rc) {
2168 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
2169 		free(port);
2170 		pthread_mutex_unlock(&rtransport->lock);
2171 		return -EINVAL;
2172 	}
2173 
2174 	rc = rdma_bind_addr(port->id, res->ai_addr);
2175 	freeaddrinfo(res);
2176 
2177 	if (rc < 0) {
2178 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
2179 		rdma_destroy_id(port->id);
2180 		free(port);
2181 		pthread_mutex_unlock(&rtransport->lock);
2182 		return rc;
2183 	}
2184 
2185 	if (!port->id->verbs) {
2186 		SPDK_ERRLOG("ibv_context is null\n");
2187 		rdma_destroy_id(port->id);
2188 		free(port);
2189 		pthread_mutex_unlock(&rtransport->lock);
2190 		return -1;
2191 	}
2192 
2193 	rc = rdma_listen(port->id, 10); /* 10 = backlog */
2194 	if (rc < 0) {
2195 		SPDK_ERRLOG("rdma_listen() failed\n");
2196 		rdma_destroy_id(port->id);
2197 		free(port);
2198 		pthread_mutex_unlock(&rtransport->lock);
2199 		return rc;
2200 	}
2201 
2202 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2203 		if (device->context == port->id->verbs) {
2204 			port->device = device;
2205 			break;
2206 		}
2207 	}
2208 	if (!port->device) {
2209 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
2210 			    port->id->verbs);
2211 		rdma_destroy_id(port->id);
2212 		free(port);
2213 		pthread_mutex_unlock(&rtransport->lock);
2214 		return -EINVAL;
2215 	}
2216 
2217 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** NVMf Target Listening on %s port %d ***\n",
2218 		     port->trid.traddr, ntohs(rdma_get_src_port(port->id)));
2219 
2220 	port->ref = 1;
2221 
2222 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
2223 	pthread_mutex_unlock(&rtransport->lock);
2224 
2225 	return 0;
2226 }
2227 
2228 static int
2229 spdk_nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
2230 			   const struct spdk_nvme_transport_id *_trid)
2231 {
2232 	struct spdk_nvmf_rdma_transport *rtransport;
2233 	struct spdk_nvmf_rdma_port *port, *tmp;
2234 	struct spdk_nvme_transport_id trid = {};
2235 
2236 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2237 
2238 	/* Selectively copy the trid. Things like NQN don't matter here - that
2239 	 * mapping is enforced elsewhere.
2240 	 */
2241 	trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
2242 	trid.adrfam = _trid->adrfam;
2243 	snprintf(trid.traddr, sizeof(port->trid.traddr), "%s", _trid->traddr);
2244 	snprintf(trid.trsvcid, sizeof(port->trid.trsvcid), "%s", _trid->trsvcid);
2245 
2246 	pthread_mutex_lock(&rtransport->lock);
2247 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
2248 		if (spdk_nvme_transport_id_compare(&port->trid, &trid) == 0) {
2249 			assert(port->ref > 0);
2250 			port->ref--;
2251 			if (port->ref == 0) {
2252 				TAILQ_REMOVE(&rtransport->ports, port, link);
2253 				rdma_destroy_id(port->id);
2254 				free(port);
2255 			}
2256 			break;
2257 		}
2258 	}
2259 
2260 	pthread_mutex_unlock(&rtransport->lock);
2261 	return 0;
2262 }
2263 
2264 static void
2265 spdk_nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
2266 				     struct spdk_nvmf_rdma_qpair *rqpair, bool drain)
2267 {
2268 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
2269 	struct spdk_nvmf_rdma_resources *resources;
2270 
2271 	/* We process I/O in the data transfer pending queue at the highest priority. RDMA reads first */
2272 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_read_queue, state_link, req_tmp) {
2273 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2274 			break;
2275 		}
2276 	}
2277 
2278 	/* Then RDMA writes since reads have stronger restrictions than writes */
2279 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_write_queue, state_link, req_tmp) {
2280 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2281 			break;
2282 		}
2283 	}
2284 
2285 	/* The second highest priority is I/O waiting on memory buffers. */
2286 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->poller->group->pending_data_buf_queue, link,
2287 			   req_tmp) {
2288 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2289 			break;
2290 		}
2291 	}
2292 
2293 	resources = rqpair->resources;
2294 	while (!STAILQ_EMPTY(&resources->free_queue) && !STAILQ_EMPTY(&resources->incoming_queue)) {
2295 		rdma_req = STAILQ_FIRST(&resources->free_queue);
2296 		STAILQ_REMOVE_HEAD(&resources->free_queue, state_link);
2297 		rdma_req->recv = STAILQ_FIRST(&resources->incoming_queue);
2298 		STAILQ_REMOVE_HEAD(&resources->incoming_queue, link);
2299 
2300 		if (rqpair->srq != NULL) {
2301 			rdma_req->req.qpair = &rdma_req->recv->qpair->qpair;
2302 			rdma_req->recv->qpair->qd++;
2303 		} else {
2304 			rqpair->qd++;
2305 		}
2306 
2307 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
2308 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false) {
2309 			break;
2310 		}
2311 	}
2312 }
2313 
2314 static void
2315 _nvmf_rdma_qpair_disconnect(void *ctx)
2316 {
2317 	struct spdk_nvmf_qpair *qpair = ctx;
2318 
2319 	spdk_nvmf_qpair_disconnect(qpair, NULL, NULL);
2320 }
2321 
2322 static void
2323 _nvmf_rdma_try_disconnect(void *ctx)
2324 {
2325 	struct spdk_nvmf_qpair *qpair = ctx;
2326 	struct spdk_nvmf_poll_group *group;
2327 
2328 	/* Read the group out of the qpair. This is normally set and accessed only from
2329 	 * the thread that created the group. Here, we're not on that thread necessarily.
2330 	 * The data member qpair->group begins it's life as NULL and then is assigned to
2331 	 * a pointer and never changes. So fortunately reading this and checking for
2332 	 * non-NULL is thread safe in the x86_64 memory model. */
2333 	group = qpair->group;
2334 
2335 	if (group == NULL) {
2336 		/* The qpair hasn't been assigned to a group yet, so we can't
2337 		 * process a disconnect. Send a message to ourself and try again. */
2338 		spdk_thread_send_msg(spdk_get_thread(), _nvmf_rdma_try_disconnect, qpair);
2339 		return;
2340 	}
2341 
2342 	spdk_thread_send_msg(group->thread, _nvmf_rdma_qpair_disconnect, qpair);
2343 }
2344 
2345 static inline void
2346 spdk_nvmf_rdma_start_disconnect(struct spdk_nvmf_rdma_qpair *rqpair)
2347 {
2348 	if (__sync_bool_compare_and_swap(&rqpair->disconnect_started, false, true)) {
2349 		_nvmf_rdma_try_disconnect(&rqpair->qpair);
2350 	}
2351 }
2352 
2353 static void nvmf_rdma_destroy_drained_qpair(void *ctx)
2354 {
2355 	struct spdk_nvmf_rdma_qpair *rqpair = ctx;
2356 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
2357 			struct spdk_nvmf_rdma_transport, transport);
2358 
2359 	/* In non SRQ path, we will reach rqpair->max_queue_depth. In SRQ path, we will get the last_wqe event. */
2360 	if (rqpair->current_send_depth != 0) {
2361 		return;
2362 	}
2363 
2364 	if (rqpair->srq == NULL && rqpair->current_recv_depth != rqpair->max_queue_depth) {
2365 		return;
2366 	}
2367 
2368 	if (rqpair->srq != NULL && rqpair->last_wqe_reached == false) {
2369 		return;
2370 	}
2371 
2372 	spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
2373 	spdk_nvmf_rdma_qpair_destroy(rqpair);
2374 }
2375 
2376 
2377 static int
2378 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
2379 {
2380 	struct spdk_nvmf_qpair		*qpair;
2381 	struct spdk_nvmf_rdma_qpair	*rqpair;
2382 
2383 	if (evt->id == NULL) {
2384 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
2385 		return -1;
2386 	}
2387 
2388 	qpair = evt->id->context;
2389 	if (qpair == NULL) {
2390 		SPDK_ERRLOG("disconnect request: no active connection\n");
2391 		return -1;
2392 	}
2393 
2394 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2395 
2396 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair->cm_id, 0);
2397 
2398 	spdk_nvmf_rdma_update_ibv_state(rqpair);
2399 
2400 	spdk_nvmf_rdma_start_disconnect(rqpair);
2401 
2402 	return 0;
2403 }
2404 
2405 #ifdef DEBUG
2406 static const char *CM_EVENT_STR[] = {
2407 	"RDMA_CM_EVENT_ADDR_RESOLVED",
2408 	"RDMA_CM_EVENT_ADDR_ERROR",
2409 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
2410 	"RDMA_CM_EVENT_ROUTE_ERROR",
2411 	"RDMA_CM_EVENT_CONNECT_REQUEST",
2412 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
2413 	"RDMA_CM_EVENT_CONNECT_ERROR",
2414 	"RDMA_CM_EVENT_UNREACHABLE",
2415 	"RDMA_CM_EVENT_REJECTED",
2416 	"RDMA_CM_EVENT_ESTABLISHED",
2417 	"RDMA_CM_EVENT_DISCONNECTED",
2418 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
2419 	"RDMA_CM_EVENT_MULTICAST_JOIN",
2420 	"RDMA_CM_EVENT_MULTICAST_ERROR",
2421 	"RDMA_CM_EVENT_ADDR_CHANGE",
2422 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
2423 };
2424 #endif /* DEBUG */
2425 
2426 static void
2427 spdk_nvmf_process_cm_event(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
2428 {
2429 	struct spdk_nvmf_rdma_transport *rtransport;
2430 	struct rdma_cm_event		*event;
2431 	int				rc;
2432 
2433 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2434 
2435 	if (rtransport->event_channel == NULL) {
2436 		return;
2437 	}
2438 
2439 	while (1) {
2440 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
2441 		if (rc == 0) {
2442 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
2443 
2444 			spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
2445 
2446 			switch (event->event) {
2447 			case RDMA_CM_EVENT_ADDR_RESOLVED:
2448 			case RDMA_CM_EVENT_ADDR_ERROR:
2449 			case RDMA_CM_EVENT_ROUTE_RESOLVED:
2450 			case RDMA_CM_EVENT_ROUTE_ERROR:
2451 				/* No action required. The target never attempts to resolve routes. */
2452 				break;
2453 			case RDMA_CM_EVENT_CONNECT_REQUEST:
2454 				rc = nvmf_rdma_connect(transport, event, cb_fn);
2455 				if (rc < 0) {
2456 					SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
2457 					break;
2458 				}
2459 				break;
2460 			case RDMA_CM_EVENT_CONNECT_RESPONSE:
2461 				/* The target never initiates a new connection. So this will not occur. */
2462 				break;
2463 			case RDMA_CM_EVENT_CONNECT_ERROR:
2464 				/* Can this happen? The docs say it can, but not sure what causes it. */
2465 				break;
2466 			case RDMA_CM_EVENT_UNREACHABLE:
2467 			case RDMA_CM_EVENT_REJECTED:
2468 				/* These only occur on the client side. */
2469 				break;
2470 			case RDMA_CM_EVENT_ESTABLISHED:
2471 				/* TODO: Should we be waiting for this event anywhere? */
2472 				break;
2473 			case RDMA_CM_EVENT_DISCONNECTED:
2474 			case RDMA_CM_EVENT_DEVICE_REMOVAL:
2475 				rc = nvmf_rdma_disconnect(event);
2476 				if (rc < 0) {
2477 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2478 					break;
2479 				}
2480 				break;
2481 			case RDMA_CM_EVENT_MULTICAST_JOIN:
2482 			case RDMA_CM_EVENT_MULTICAST_ERROR:
2483 				/* Multicast is not used */
2484 				break;
2485 			case RDMA_CM_EVENT_ADDR_CHANGE:
2486 				/* Not utilizing this event */
2487 				break;
2488 			case RDMA_CM_EVENT_TIMEWAIT_EXIT:
2489 				/* For now, do nothing. The target never re-uses queue pairs. */
2490 				break;
2491 			default:
2492 				SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
2493 				break;
2494 			}
2495 
2496 			rdma_ack_cm_event(event);
2497 		} else {
2498 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
2499 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
2500 			}
2501 			break;
2502 		}
2503 	}
2504 }
2505 
2506 static void
2507 spdk_nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
2508 {
2509 	int				rc;
2510 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
2511 	struct ibv_async_event		event;
2512 	enum ibv_qp_state		state;
2513 
2514 	rc = ibv_get_async_event(device->context, &event);
2515 
2516 	if (rc) {
2517 		SPDK_ERRLOG("Failed to get async_event (%d): %s\n",
2518 			    errno, spdk_strerror(errno));
2519 		return;
2520 	}
2521 
2522 	SPDK_NOTICELOG("Async event: %s\n",
2523 		       ibv_event_type_str(event.event_type));
2524 
2525 	switch (event.event_type) {
2526 	case IBV_EVENT_QP_FATAL:
2527 		rqpair = event.element.qp->qp_context;
2528 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
2529 				  (uintptr_t)rqpair->cm_id, event.event_type);
2530 		spdk_nvmf_rdma_update_ibv_state(rqpair);
2531 		spdk_nvmf_rdma_start_disconnect(rqpair);
2532 		break;
2533 	case IBV_EVENT_QP_LAST_WQE_REACHED:
2534 		/* This event only occurs for shared receive queues. */
2535 		rqpair = event.element.qp->qp_context;
2536 		rqpair->last_wqe_reached = true;
2537 
2538 		/* This must be handled on the polling thread if it exists. Otherwise the timeout will catch it. */
2539 		if (rqpair->qpair.group) {
2540 			spdk_thread_send_msg(rqpair->qpair.group->thread, nvmf_rdma_destroy_drained_qpair, rqpair);
2541 		} else {
2542 			SPDK_ERRLOG("Unable to destroy the qpair %p since it does not have a poll group.\n", rqpair);
2543 		}
2544 
2545 		break;
2546 	case IBV_EVENT_SQ_DRAINED:
2547 		/* This event occurs frequently in both error and non-error states.
2548 		 * Check if the qpair is in an error state before sending a message.
2549 		 * Note that we're not on the correct thread to access the qpair, but
2550 		 * the operations that the below calls make all happen to be thread
2551 		 * safe. */
2552 		rqpair = event.element.qp->qp_context;
2553 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
2554 				  (uintptr_t)rqpair->cm_id, event.event_type);
2555 		state = spdk_nvmf_rdma_update_ibv_state(rqpair);
2556 		if (state == IBV_QPS_ERR) {
2557 			spdk_nvmf_rdma_start_disconnect(rqpair);
2558 		}
2559 		break;
2560 	case IBV_EVENT_QP_REQ_ERR:
2561 	case IBV_EVENT_QP_ACCESS_ERR:
2562 	case IBV_EVENT_COMM_EST:
2563 	case IBV_EVENT_PATH_MIG:
2564 	case IBV_EVENT_PATH_MIG_ERR:
2565 		rqpair = event.element.qp->qp_context;
2566 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
2567 				  (uintptr_t)rqpair->cm_id, event.event_type);
2568 		spdk_nvmf_rdma_update_ibv_state(rqpair);
2569 		break;
2570 	case IBV_EVENT_CQ_ERR:
2571 	case IBV_EVENT_DEVICE_FATAL:
2572 	case IBV_EVENT_PORT_ACTIVE:
2573 	case IBV_EVENT_PORT_ERR:
2574 	case IBV_EVENT_LID_CHANGE:
2575 	case IBV_EVENT_PKEY_CHANGE:
2576 	case IBV_EVENT_SM_CHANGE:
2577 	case IBV_EVENT_SRQ_ERR:
2578 	case IBV_EVENT_SRQ_LIMIT_REACHED:
2579 	case IBV_EVENT_CLIENT_REREGISTER:
2580 	case IBV_EVENT_GID_CHANGE:
2581 	default:
2582 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
2583 		break;
2584 	}
2585 	ibv_ack_async_event(&event);
2586 }
2587 
2588 static void
2589 spdk_nvmf_rdma_accept(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
2590 {
2591 	int	nfds, i = 0;
2592 	struct spdk_nvmf_rdma_transport *rtransport;
2593 	struct spdk_nvmf_rdma_device *device, *tmp;
2594 
2595 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2596 	nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
2597 
2598 	if (nfds <= 0) {
2599 		return;
2600 	}
2601 
2602 	/* The first poll descriptor is RDMA CM event */
2603 	if (rtransport->poll_fds[i++].revents & POLLIN) {
2604 		spdk_nvmf_process_cm_event(transport, cb_fn);
2605 		nfds--;
2606 	}
2607 
2608 	if (nfds == 0) {
2609 		return;
2610 	}
2611 
2612 	/* Second and subsequent poll descriptors are IB async events */
2613 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2614 		if (rtransport->poll_fds[i++].revents & POLLIN) {
2615 			spdk_nvmf_process_ib_event(device);
2616 			nfds--;
2617 		}
2618 	}
2619 	/* check all flagged fd's have been served */
2620 	assert(nfds == 0);
2621 }
2622 
2623 static void
2624 spdk_nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
2625 			struct spdk_nvme_transport_id *trid,
2626 			struct spdk_nvmf_discovery_log_page_entry *entry)
2627 {
2628 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
2629 	entry->adrfam = trid->adrfam;
2630 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_SPECIFIED;
2631 
2632 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
2633 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
2634 
2635 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
2636 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
2637 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
2638 }
2639 
2640 static void
2641 spdk_nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
2642 
2643 static struct spdk_nvmf_transport_poll_group *
2644 spdk_nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
2645 {
2646 	struct spdk_nvmf_rdma_transport		*rtransport;
2647 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2648 	struct spdk_nvmf_rdma_poller		*poller;
2649 	struct spdk_nvmf_rdma_device		*device;
2650 	struct ibv_srq_init_attr		srq_init_attr;
2651 	struct spdk_nvmf_rdma_resource_opts	opts;
2652 	int					num_cqe;
2653 
2654 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2655 
2656 	rgroup = calloc(1, sizeof(*rgroup));
2657 	if (!rgroup) {
2658 		return NULL;
2659 	}
2660 
2661 	TAILQ_INIT(&rgroup->pollers);
2662 	TAILQ_INIT(&rgroup->pending_data_buf_queue);
2663 
2664 	pthread_mutex_lock(&rtransport->lock);
2665 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2666 		poller = calloc(1, sizeof(*poller));
2667 		if (!poller) {
2668 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
2669 			spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
2670 			pthread_mutex_unlock(&rtransport->lock);
2671 			return NULL;
2672 		}
2673 
2674 		poller->device = device;
2675 		poller->group = rgroup;
2676 
2677 		TAILQ_INIT(&poller->qpairs);
2678 
2679 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
2680 		if (device->attr.max_srq != 0) {
2681 			poller->max_srq_depth = transport->opts.max_srq_depth;
2682 
2683 			memset(&srq_init_attr, 0, sizeof(struct ibv_srq_init_attr));
2684 			srq_init_attr.attr.max_wr = poller->max_srq_depth;
2685 			srq_init_attr.attr.max_sge = spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
2686 			poller->srq = ibv_create_srq(device->pd, &srq_init_attr);
2687 			if (!poller->srq) {
2688 				SPDK_ERRLOG("Unable to create shared receive queue, errno %d\n", errno);
2689 				spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
2690 				pthread_mutex_unlock(&rtransport->lock);
2691 				return NULL;
2692 			}
2693 
2694 			opts.qp = poller->srq;
2695 			opts.pd = device->pd;
2696 			opts.qpair = NULL;
2697 			opts.shared = true;
2698 			opts.max_queue_depth = poller->max_srq_depth;
2699 			opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
2700 
2701 			poller->resources = nvmf_rdma_resources_create(&opts);
2702 			if (!poller->resources) {
2703 				SPDK_ERRLOG("Unable to allocate resources for shared receive queue.\n");
2704 				spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
2705 				pthread_mutex_unlock(&rtransport->lock);
2706 			}
2707 		}
2708 
2709 		/*
2710 		 * When using an srq, we can limit the completion queue at startup.
2711 		 * The following formula represents the calculation:
2712 		 * num_cqe = num_recv + num_data_wr + num_send_wr.
2713 		 * where num_recv=num_data_wr=and num_send_wr=poller->max_srq_depth
2714 		 */
2715 		if (poller->srq) {
2716 			num_cqe = poller->max_srq_depth * 3;
2717 		} else {
2718 			num_cqe = DEFAULT_NVMF_RDMA_CQ_SIZE;
2719 		}
2720 
2721 		poller->cq = ibv_create_cq(device->context, num_cqe, poller, NULL, 0);
2722 		if (!poller->cq) {
2723 			SPDK_ERRLOG("Unable to create completion queue\n");
2724 			spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
2725 			pthread_mutex_unlock(&rtransport->lock);
2726 			return NULL;
2727 		}
2728 		poller->num_cqe = num_cqe;
2729 	}
2730 
2731 	pthread_mutex_unlock(&rtransport->lock);
2732 	return &rgroup->group;
2733 }
2734 
2735 static void
2736 spdk_nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
2737 {
2738 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2739 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
2740 	struct spdk_nvmf_rdma_qpair		*qpair, *tmp_qpair;
2741 
2742 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
2743 
2744 	if (!rgroup) {
2745 		return;
2746 	}
2747 
2748 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
2749 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
2750 
2751 		TAILQ_FOREACH_SAFE(qpair, &poller->qpairs, link, tmp_qpair) {
2752 			spdk_nvmf_rdma_qpair_destroy(qpair);
2753 		}
2754 
2755 		if (poller->srq) {
2756 			nvmf_rdma_resources_destroy(poller->resources);
2757 			ibv_destroy_srq(poller->srq);
2758 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Destroyed RDMA shared queue %p\n", poller->srq);
2759 		}
2760 
2761 		if (poller->cq) {
2762 			ibv_destroy_cq(poller->cq);
2763 		}
2764 
2765 		free(poller);
2766 	}
2767 
2768 	if (!TAILQ_EMPTY(&rgroup->pending_data_buf_queue)) {
2769 		SPDK_ERRLOG("Pending I/O list wasn't empty on poll group destruction\n");
2770 	}
2771 
2772 	free(rgroup);
2773 }
2774 
2775 static void
2776 spdk_nvmf_rdma_qpair_reject_connection(struct spdk_nvmf_rdma_qpair *rqpair)
2777 {
2778 	spdk_nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
2779 	spdk_nvmf_rdma_qpair_destroy(rqpair);
2780 }
2781 
2782 static int
2783 spdk_nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
2784 			      struct spdk_nvmf_qpair *qpair)
2785 {
2786 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2787 	struct spdk_nvmf_rdma_qpair		*rqpair;
2788 	struct spdk_nvmf_rdma_device		*device;
2789 	struct spdk_nvmf_rdma_poller		*poller;
2790 	int					rc;
2791 
2792 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
2793 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2794 
2795 	device = rqpair->port->device;
2796 
2797 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
2798 		if (poller->device == device) {
2799 			break;
2800 		}
2801 	}
2802 
2803 	if (!poller) {
2804 		SPDK_ERRLOG("No poller found for device.\n");
2805 		return -1;
2806 	}
2807 
2808 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
2809 	rqpair->poller = poller;
2810 	rqpair->srq = rqpair->poller->srq;
2811 
2812 	rc = spdk_nvmf_rdma_qpair_initialize(qpair);
2813 	if (rc < 0) {
2814 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
2815 		return -1;
2816 	}
2817 
2818 	rc = spdk_nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
2819 	if (rc) {
2820 		/* Try to reject, but we probably can't */
2821 		spdk_nvmf_rdma_qpair_reject_connection(rqpair);
2822 		return -1;
2823 	}
2824 
2825 	spdk_nvmf_rdma_update_ibv_state(rqpair);
2826 
2827 	return 0;
2828 }
2829 
2830 static int
2831 spdk_nvmf_rdma_request_free(struct spdk_nvmf_request *req)
2832 {
2833 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
2834 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
2835 			struct spdk_nvmf_rdma_transport, transport);
2836 
2837 	nvmf_rdma_request_free(rdma_req, rtransport);
2838 	return 0;
2839 }
2840 
2841 static int
2842 spdk_nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
2843 {
2844 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
2845 			struct spdk_nvmf_rdma_transport, transport);
2846 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
2847 			struct spdk_nvmf_rdma_request, req);
2848 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
2849 			struct spdk_nvmf_rdma_qpair, qpair);
2850 
2851 	if (rqpair->ibv_attr.qp_state != IBV_QPS_ERR) {
2852 		/* The connection is alive, so process the request as normal */
2853 		rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
2854 	} else {
2855 		/* The connection is dead. Move the request directly to the completed state. */
2856 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2857 	}
2858 
2859 	spdk_nvmf_rdma_request_process(rtransport, rdma_req);
2860 
2861 	return 0;
2862 }
2863 
2864 static int
2865 spdk_nvmf_rdma_destroy_defunct_qpair(void *ctx)
2866 {
2867 	struct spdk_nvmf_rdma_qpair	*rqpair = ctx;
2868 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
2869 			struct spdk_nvmf_rdma_transport, transport);
2870 
2871 	spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
2872 	spdk_nvmf_rdma_qpair_destroy(rqpair);
2873 
2874 	return 0;
2875 }
2876 
2877 static void
2878 spdk_nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair)
2879 {
2880 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2881 
2882 	if (rqpair->disconnect_flags & RDMA_QP_DISCONNECTING) {
2883 		return;
2884 	}
2885 
2886 	rqpair->disconnect_flags |= RDMA_QP_DISCONNECTING;
2887 
2888 	/* This happens only when the qpair is disconnected before
2889 	 * it is added to the poll group. Since there is no poll group,
2890 	 * the RDMA qp has not been initialized yet and the RDMA CM
2891 	 * event has not yet been acknowledged, so we need to reject it.
2892 	 */
2893 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
2894 		spdk_nvmf_rdma_qpair_reject_connection(rqpair);
2895 		return;
2896 	}
2897 
2898 	if (rqpair->ibv_attr.qp_state != IBV_QPS_ERR) {
2899 		spdk_nvmf_rdma_set_ibv_state(rqpair, IBV_QPS_ERR);
2900 	}
2901 
2902 	rqpair->destruct_poller = spdk_poller_register(spdk_nvmf_rdma_destroy_defunct_qpair, (void *)rqpair,
2903 				  NVMF_RDMA_QPAIR_DESTROY_TIMEOUT_US);
2904 }
2905 
2906 static struct spdk_nvmf_rdma_qpair *
2907 get_rdma_qpair_from_wc(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_wc *wc)
2908 {
2909 	struct spdk_nvmf_rdma_qpair *rqpair;
2910 	/* @todo: improve QP search */
2911 	TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
2912 		if (wc->qp_num == rqpair->cm_id->qp->qp_num) {
2913 			return rqpair;
2914 		}
2915 	}
2916 	SPDK_ERRLOG("Didn't find QP with qp_num %u\n", wc->qp_num);
2917 	return NULL;
2918 }
2919 
2920 #ifdef DEBUG
2921 static int
2922 spdk_nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
2923 {
2924 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
2925 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
2926 }
2927 #endif
2928 
2929 static int
2930 spdk_nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
2931 			   struct spdk_nvmf_rdma_poller *rpoller)
2932 {
2933 	struct ibv_wc wc[32];
2934 	struct spdk_nvmf_rdma_wr	*rdma_wr;
2935 	struct spdk_nvmf_rdma_request	*rdma_req;
2936 	struct spdk_nvmf_rdma_recv	*rdma_recv;
2937 	struct spdk_nvmf_rdma_qpair	*rqpair;
2938 	int reaped, i;
2939 	int count = 0;
2940 	bool error = false;
2941 
2942 	/* Poll for completing operations. */
2943 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
2944 	if (reaped < 0) {
2945 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
2946 			    errno, spdk_strerror(errno));
2947 		return -1;
2948 	}
2949 
2950 	for (i = 0; i < reaped; i++) {
2951 
2952 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
2953 
2954 		/* Handle error conditions */
2955 		if (wc[i].status) {
2956 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "CQ error on CQ %p, Request 0x%lu (%d): %s\n",
2957 				      rpoller->cq, wc[i].wr_id, wc[i].status, ibv_wc_status_str(wc[i].status));
2958 
2959 			error = true;
2960 
2961 			switch (rdma_wr->type) {
2962 			case RDMA_WR_TYPE_SEND:
2963 				rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
2964 				rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
2965 
2966 				SPDK_ERRLOG("data=%p length=%u\n", rdma_req->req.data, rdma_req->req.length);
2967 				/* We're going to attempt an error recovery, so force the request into
2968 				 * the completed state. */
2969 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2970 				rqpair->current_send_depth--;
2971 
2972 				assert(rdma_req->num_outstanding_data_wr == 0);
2973 				spdk_nvmf_rdma_request_process(rtransport, rdma_req);
2974 				break;
2975 			case RDMA_WR_TYPE_RECV:
2976 				/* rdma_recv->qpair will be NULL if using an SRQ.  In that case we have to get the qpair from the wc. */
2977 				rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
2978 				if (rdma_recv->qpair == NULL) {
2979 					rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
2980 				}
2981 				rqpair = rdma_recv->qpair;
2982 
2983 				assert(rqpair != NULL);
2984 
2985 				/* Dump this into the incoming queue. This gets cleaned up when
2986 				 * the queue pair disconnects or recovers. */
2987 				STAILQ_INSERT_TAIL(&rqpair->resources->incoming_queue, rdma_recv, link);
2988 				rqpair->current_recv_depth++;
2989 				break;
2990 			case RDMA_WR_TYPE_DATA:
2991 				/* If the data transfer fails still force the queue into the error state,
2992 				 * if we were performing an RDMA_READ, we need to force the request into a
2993 				 * completed state since it wasn't linked to a send. However, in the RDMA_WRITE
2994 				 * case, we should wait for the SEND to complete. */
2995 				rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
2996 				rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
2997 
2998 				SPDK_ERRLOG("data=%p length=%u\n", rdma_req->req.data, rdma_req->req.length);
2999 				assert(rdma_req->num_outstanding_data_wr > 0);
3000 				rdma_req->num_outstanding_data_wr--;
3001 				if (rdma_req->data.wr.opcode == IBV_WR_RDMA_READ) {
3002 					rqpair->current_read_depth--;
3003 					if (rdma_req->num_outstanding_data_wr == 0) {
3004 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3005 					}
3006 				}
3007 				rqpair->current_send_depth--;
3008 				break;
3009 			default:
3010 				SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
3011 				continue;
3012 			}
3013 
3014 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3015 				/* Disconnect the connection. */
3016 				spdk_nvmf_rdma_start_disconnect(rqpair);
3017 			} else {
3018 				nvmf_rdma_destroy_drained_qpair(rqpair);
3019 			}
3020 			continue;
3021 		}
3022 
3023 		switch (wc[i].opcode) {
3024 		case IBV_WC_SEND:
3025 			assert(rdma_wr->type == RDMA_WR_TYPE_SEND);
3026 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3027 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3028 
3029 			assert(spdk_nvmf_rdma_req_is_completing(rdma_req));
3030 
3031 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3032 			rqpair->current_send_depth--;
3033 			spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3034 
3035 			count++;
3036 
3037 			assert(rdma_req->num_outstanding_data_wr == 0);
3038 			/* Try to process other queued requests */
3039 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3040 			break;
3041 
3042 		case IBV_WC_RDMA_WRITE:
3043 			assert(rdma_wr->type == RDMA_WR_TYPE_DATA);
3044 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3045 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3046 			rqpair->current_send_depth--;
3047 			rdma_req->num_outstanding_data_wr--;
3048 
3049 			/* Try to process other queued requests */
3050 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3051 			break;
3052 
3053 		case IBV_WC_RDMA_READ:
3054 			assert(rdma_wr->type == RDMA_WR_TYPE_DATA);
3055 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3056 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3057 			rqpair->current_send_depth--;
3058 
3059 			assert(rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
3060 			/* wait for all outstanding reads associated with the same rdma_req to complete before proceeding. */
3061 			assert(rdma_req->num_outstanding_data_wr > 0);
3062 			rqpair->current_read_depth--;
3063 			rdma_req->num_outstanding_data_wr--;
3064 			if (rdma_req->num_outstanding_data_wr == 0) {
3065 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
3066 				spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3067 			}
3068 
3069 			/* Try to process other queued requests */
3070 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3071 			break;
3072 
3073 		case IBV_WC_RECV:
3074 			assert(rdma_wr->type == RDMA_WR_TYPE_RECV);
3075 			/* rdma_recv->qpair will be NULL if using an SRQ.  In that case we have to get the qpair from the wc. */
3076 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3077 			if (rdma_recv->qpair == NULL) {
3078 				rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
3079 			}
3080 			rqpair = rdma_recv->qpair;
3081 			/* The qpair should not send more requests than are allowed per qpair. */
3082 			if (rqpair->current_recv_depth >= rqpair->max_queue_depth) {
3083 				spdk_nvmf_rdma_start_disconnect(rqpair);
3084 			} else {
3085 				rqpair->current_recv_depth++;
3086 			}
3087 
3088 			STAILQ_INSERT_TAIL(&rqpair->resources->incoming_queue, rdma_recv, link);
3089 			/* Try to process other queued requests */
3090 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3091 			break;
3092 
3093 		default:
3094 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
3095 			continue;
3096 		}
3097 
3098 		if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
3099 			nvmf_rdma_destroy_drained_qpair(rqpair);
3100 		}
3101 	}
3102 
3103 	if (error == true) {
3104 		return -1;
3105 	}
3106 
3107 	return count;
3108 }
3109 
3110 static int
3111 spdk_nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3112 {
3113 	struct spdk_nvmf_rdma_transport *rtransport;
3114 	struct spdk_nvmf_rdma_poll_group *rgroup;
3115 	struct spdk_nvmf_rdma_poller	*rpoller;
3116 	int				count, rc;
3117 
3118 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
3119 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3120 
3121 	count = 0;
3122 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3123 		rc = spdk_nvmf_rdma_poller_poll(rtransport, rpoller);
3124 		if (rc < 0) {
3125 			return rc;
3126 		}
3127 		count += rc;
3128 	}
3129 
3130 	return count;
3131 }
3132 
3133 static int
3134 spdk_nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
3135 			       struct spdk_nvme_transport_id *trid,
3136 			       bool peer)
3137 {
3138 	struct sockaddr *saddr;
3139 	uint16_t port;
3140 
3141 	trid->trtype = SPDK_NVME_TRANSPORT_RDMA;
3142 
3143 	if (peer) {
3144 		saddr = rdma_get_peer_addr(id);
3145 	} else {
3146 		saddr = rdma_get_local_addr(id);
3147 	}
3148 	switch (saddr->sa_family) {
3149 	case AF_INET: {
3150 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
3151 
3152 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3153 		inet_ntop(AF_INET, &saddr_in->sin_addr,
3154 			  trid->traddr, sizeof(trid->traddr));
3155 		if (peer) {
3156 			port = ntohs(rdma_get_dst_port(id));
3157 		} else {
3158 			port = ntohs(rdma_get_src_port(id));
3159 		}
3160 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3161 		break;
3162 	}
3163 	case AF_INET6: {
3164 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
3165 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3166 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
3167 			  trid->traddr, sizeof(trid->traddr));
3168 		if (peer) {
3169 			port = ntohs(rdma_get_dst_port(id));
3170 		} else {
3171 			port = ntohs(rdma_get_src_port(id));
3172 		}
3173 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3174 		break;
3175 	}
3176 	default:
3177 		return -1;
3178 
3179 	}
3180 
3181 	return 0;
3182 }
3183 
3184 static int
3185 spdk_nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
3186 				   struct spdk_nvme_transport_id *trid)
3187 {
3188 	struct spdk_nvmf_rdma_qpair	*rqpair;
3189 
3190 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3191 
3192 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
3193 }
3194 
3195 static int
3196 spdk_nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
3197 				    struct spdk_nvme_transport_id *trid)
3198 {
3199 	struct spdk_nvmf_rdma_qpair	*rqpair;
3200 
3201 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3202 
3203 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
3204 }
3205 
3206 static int
3207 spdk_nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
3208 				     struct spdk_nvme_transport_id *trid)
3209 {
3210 	struct spdk_nvmf_rdma_qpair	*rqpair;
3211 
3212 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3213 
3214 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
3215 }
3216 
3217 void
3218 spdk_nvmf_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
3219 {
3220 	g_nvmf_hooks = *hooks;
3221 }
3222 
3223 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
3224 	.type = SPDK_NVME_TRANSPORT_RDMA,
3225 	.opts_init = spdk_nvmf_rdma_opts_init,
3226 	.create = spdk_nvmf_rdma_create,
3227 	.destroy = spdk_nvmf_rdma_destroy,
3228 
3229 	.listen = spdk_nvmf_rdma_listen,
3230 	.stop_listen = spdk_nvmf_rdma_stop_listen,
3231 	.accept = spdk_nvmf_rdma_accept,
3232 
3233 	.listener_discover = spdk_nvmf_rdma_discover,
3234 
3235 	.poll_group_create = spdk_nvmf_rdma_poll_group_create,
3236 	.poll_group_destroy = spdk_nvmf_rdma_poll_group_destroy,
3237 	.poll_group_add = spdk_nvmf_rdma_poll_group_add,
3238 	.poll_group_poll = spdk_nvmf_rdma_poll_group_poll,
3239 
3240 	.req_free = spdk_nvmf_rdma_request_free,
3241 	.req_complete = spdk_nvmf_rdma_request_complete,
3242 
3243 	.qpair_fini = spdk_nvmf_rdma_close_qpair,
3244 	.qpair_get_peer_trid = spdk_nvmf_rdma_qpair_get_peer_trid,
3245 	.qpair_get_local_trid = spdk_nvmf_rdma_qpair_get_local_trid,
3246 	.qpair_get_listen_trid = spdk_nvmf_rdma_qpair_get_listen_trid,
3247 
3248 };
3249 
3250 SPDK_LOG_REGISTER_COMPONENT("rdma", SPDK_LOG_RDMA)
3251