xref: /spdk/lib/nvmf/rdma.c (revision 8fb123553a690dca615baec02990aa0dc2c655d0)
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 /*
55  RDMA Connection Resource Defaults
56  */
57 #define NVMF_DEFAULT_TX_SGE		1
58 #define NVMF_DEFAULT_RX_SGE		2
59 #define NVMF_DEFAULT_DATA_SGE		16
60 
61 /* The RDMA completion queue size */
62 #define NVMF_RDMA_CQ_SIZE	4096
63 
64 /* AIO backend requires block size aligned data buffers,
65  * extra 4KiB aligned data buffer should work for most devices.
66  */
67 #define SHIFT_4KB			12
68 #define NVMF_DATA_BUFFER_ALIGNMENT	(1 << SHIFT_4KB)
69 #define NVMF_DATA_BUFFER_MASK		(NVMF_DATA_BUFFER_ALIGNMENT - 1)
70 
71 enum spdk_nvmf_rdma_request_state {
72 	/* The request is not currently in use */
73 	RDMA_REQUEST_STATE_FREE = 0,
74 
75 	/* Initial state when request first received */
76 	RDMA_REQUEST_STATE_NEW,
77 
78 	/* The request is queued until a data buffer is available. */
79 	RDMA_REQUEST_STATE_NEED_BUFFER,
80 
81 	/* The request is waiting on RDMA queue depth availability
82 	 * to transfer data between the host and the controller.
83 	 */
84 	RDMA_REQUEST_STATE_DATA_TRANSFER_PENDING,
85 
86 	/* The request is currently transferring data from the host to the controller. */
87 	RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
88 
89 	/* The request is ready to execute at the block device */
90 	RDMA_REQUEST_STATE_READY_TO_EXECUTE,
91 
92 	/* The request is currently executing at the block device */
93 	RDMA_REQUEST_STATE_EXECUTING,
94 
95 	/* The request finished executing at the block device */
96 	RDMA_REQUEST_STATE_EXECUTED,
97 
98 	/* The request is ready to send a completion */
99 	RDMA_REQUEST_STATE_READY_TO_COMPLETE,
100 
101 	/* The request is currently transferring data from the controller to the host. */
102 	RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
103 
104 	/* The request currently has an outstanding completion without an
105 	 * associated data transfer.
106 	 */
107 	RDMA_REQUEST_STATE_COMPLETING,
108 
109 	/* The request completed and can be marked free. */
110 	RDMA_REQUEST_STATE_COMPLETED,
111 
112 	/* Terminator */
113 	RDMA_REQUEST_NUM_STATES,
114 };
115 
116 #define OBJECT_NVMF_RDMA_IO				0x40
117 
118 #define									TRACE_GROUP_NVMF_RDMA 0x4
119 #define TRACE_RDMA_REQUEST_STATE_NEW					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x0)
120 #define TRACE_RDMA_REQUEST_STATE_NEED_BUFFER				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x1)
121 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_PENDING			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x2)
122 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x3)
123 #define TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x4)
124 #define TRACE_RDMA_REQUEST_STATE_EXECUTING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x5)
125 #define TRACE_RDMA_REQUEST_STATE_EXECUTED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x6)
126 #define TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x7)
127 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x8)
128 #define TRACE_RDMA_REQUEST_STATE_COMPLETING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x9)
129 #define TRACE_RDMA_REQUEST_STATE_COMPLETED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xA)
130 #define TRACE_RDMA_QP_CREATE						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xB)
131 #define TRACE_RDMA_IBV_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xC)
132 #define TRACE_RDMA_CM_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xD)
133 #define TRACE_RDMA_QP_STATE_CHANGE					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xE)
134 #define TRACE_RDMA_QP_DISCONNECT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xF)
135 #define TRACE_RDMA_QP_DESTROY						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x10)
136 
137 SPDK_TRACE_REGISTER_FN(nvmf_trace)
138 {
139 	spdk_trace_register_object(OBJECT_NVMF_RDMA_IO, 'r');
140 	spdk_trace_register_description("RDMA_REQ_NEW", "",
141 					TRACE_RDMA_REQUEST_STATE_NEW,
142 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 1, 1, "cmid:   ");
143 	spdk_trace_register_description("RDMA_REQ_NEED_BUFFER", "",
144 					TRACE_RDMA_REQUEST_STATE_NEED_BUFFER,
145 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
146 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_H_TO_C", "",
147 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_PENDING,
148 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
149 	spdk_trace_register_description("RDMA_REQ_TX_H_TO_C", "",
150 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
151 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
152 	spdk_trace_register_description("RDMA_REQ_RDY_TO_EXECUTE", "",
153 					TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE,
154 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
155 	spdk_trace_register_description("RDMA_REQ_EXECUTING", "",
156 					TRACE_RDMA_REQUEST_STATE_EXECUTING,
157 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
158 	spdk_trace_register_description("RDMA_REQ_EXECUTED", "",
159 					TRACE_RDMA_REQUEST_STATE_EXECUTED,
160 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
161 	spdk_trace_register_description("RDMA_REQ_RDY_TO_COMPLETE", "",
162 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE,
163 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
164 	spdk_trace_register_description("RDMA_REQ_COMPLETING_CONTROLLER_TO_HOST", "",
165 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
166 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
167 	spdk_trace_register_description("RDMA_REQ_COMPLETING_INCAPSULE", "",
168 					TRACE_RDMA_REQUEST_STATE_COMPLETING,
169 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
170 	spdk_trace_register_description("RDMA_REQ_COMPLETED", "",
171 					TRACE_RDMA_REQUEST_STATE_COMPLETED,
172 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
173 
174 	spdk_trace_register_description("RDMA_QP_CREATE", "", TRACE_RDMA_QP_CREATE,
175 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
176 	spdk_trace_register_description("RDMA_IBV_ASYNC_EVENT", "", TRACE_RDMA_IBV_ASYNC_EVENT,
177 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
178 	spdk_trace_register_description("RDMA_CM_ASYNC_EVENT", "", TRACE_RDMA_CM_ASYNC_EVENT,
179 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
180 	spdk_trace_register_description("RDMA_QP_STATE_CHANGE", "", TRACE_RDMA_QP_STATE_CHANGE,
181 					OWNER_NONE, OBJECT_NONE, 0, 1, "state:  ");
182 	spdk_trace_register_description("RDMA_QP_DISCONNECT", "", TRACE_RDMA_QP_DISCONNECT,
183 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
184 	spdk_trace_register_description("RDMA_QP_DESTROY", "", TRACE_RDMA_QP_DESTROY,
185 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
186 }
187 
188 enum spdk_nvmf_rdma_wr_type {
189 	RDMA_WR_TYPE_RECV,
190 	RDMA_WR_TYPE_SEND,
191 	RDMA_WR_TYPE_DATA,
192 	RDMA_WR_TYPE_DRAIN_SEND,
193 	RDMA_WR_TYPE_DRAIN_RECV
194 };
195 
196 struct spdk_nvmf_rdma_wr {
197 	enum spdk_nvmf_rdma_wr_type	type;
198 };
199 
200 /* This structure holds commands as they are received off the wire.
201  * It must be dynamically paired with a full request object
202  * (spdk_nvmf_rdma_request) to service a request. It is separate
203  * from the request because RDMA does not appear to order
204  * completions, so occasionally we'll get a new incoming
205  * command when there aren't any free request objects.
206  */
207 struct spdk_nvmf_rdma_recv {
208 	struct ibv_recv_wr		wr;
209 	struct ibv_sge			sgl[NVMF_DEFAULT_RX_SGE];
210 
211 	struct spdk_nvmf_rdma_qpair	*qpair;
212 
213 	/* In-capsule data buffer */
214 	uint8_t				*buf;
215 
216 	struct spdk_nvmf_rdma_wr	rdma_wr;
217 
218 	TAILQ_ENTRY(spdk_nvmf_rdma_recv) link;
219 };
220 
221 struct spdk_nvmf_rdma_request {
222 	struct spdk_nvmf_request		req;
223 	bool					data_from_pool;
224 
225 	enum spdk_nvmf_rdma_request_state	state;
226 
227 	struct spdk_nvmf_rdma_recv		*recv;
228 
229 	struct {
230 		struct spdk_nvmf_rdma_wr	rdma_wr;
231 		struct	ibv_send_wr		wr;
232 		struct	ibv_sge			sgl[NVMF_DEFAULT_TX_SGE];
233 	} rsp;
234 
235 	struct {
236 		struct spdk_nvmf_rdma_wr	rdma_wr;
237 		struct ibv_send_wr		wr;
238 		struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
239 		void				*buffers[SPDK_NVMF_MAX_SGL_ENTRIES];
240 	} data;
241 
242 	struct spdk_nvmf_rdma_wr		rdma_wr;
243 
244 	TAILQ_ENTRY(spdk_nvmf_rdma_request)	link;
245 	TAILQ_ENTRY(spdk_nvmf_rdma_request)	state_link;
246 };
247 
248 enum spdk_nvmf_rdma_qpair_disconnect_flags {
249 	RDMA_QP_DISCONNECTING		= 1,
250 	RDMA_QP_RECV_DRAINED		= 1 << 1,
251 	RDMA_QP_SEND_DRAINED		= 1 << 2
252 };
253 
254 struct spdk_nvmf_rdma_qpair {
255 	struct spdk_nvmf_qpair			qpair;
256 
257 	struct spdk_nvmf_rdma_port		*port;
258 	struct spdk_nvmf_rdma_poller		*poller;
259 
260 	struct rdma_cm_id			*cm_id;
261 	struct rdma_cm_id			*listen_id;
262 
263 	/* The maximum number of I/O outstanding on this connection at one time */
264 	uint16_t				max_queue_depth;
265 
266 	/* The maximum number of active RDMA READ and WRITE operations at one time */
267 	uint16_t				max_rw_depth;
268 
269 	/* Receives that are waiting for a request object */
270 	TAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
271 
272 	/* Queues to track the requests in all states */
273 	TAILQ_HEAD(, spdk_nvmf_rdma_request)	state_queue[RDMA_REQUEST_NUM_STATES];
274 
275 	/* Number of requests in each state */
276 	uint32_t				state_cntr[RDMA_REQUEST_NUM_STATES];
277 
278 	int                                     max_sge;
279 
280 	/* Array of size "max_queue_depth" containing RDMA requests. */
281 	struct spdk_nvmf_rdma_request		*reqs;
282 
283 	/* Array of size "max_queue_depth" containing RDMA recvs. */
284 	struct spdk_nvmf_rdma_recv		*recvs;
285 
286 	/* Array of size "max_queue_depth" containing 64 byte capsules
287 	 * used for receive.
288 	 */
289 	union nvmf_h2c_msg			*cmds;
290 	struct ibv_mr				*cmds_mr;
291 
292 	/* Array of size "max_queue_depth" containing 16 byte completions
293 	 * to be sent back to the user.
294 	 */
295 	union nvmf_c2h_msg			*cpls;
296 	struct ibv_mr				*cpls_mr;
297 
298 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
299 	 * buffers to be used for in capsule data.
300 	 */
301 	void					*bufs;
302 	struct ibv_mr				*bufs_mr;
303 
304 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	link;
305 
306 	/* Mgmt channel */
307 	struct spdk_io_channel			*mgmt_channel;
308 	struct spdk_nvmf_rdma_mgmt_channel	*ch;
309 
310 	/* IBV queue pair attributes: they are used to manage
311 	 * qp state and recover from errors.
312 	 */
313 	struct ibv_qp_init_attr			ibv_init_attr;
314 	struct ibv_qp_attr			ibv_attr;
315 
316 	uint32_t				disconnect_flags;
317 	struct spdk_nvmf_rdma_wr		drain_send_wr;
318 	struct spdk_nvmf_rdma_wr		drain_recv_wr;
319 
320 	/* Reference counter for how many unprocessed messages
321 	 * from other threads are currently outstanding. The
322 	 * qpair cannot be destroyed until this is 0. This is
323 	 * atomically incremented from any thread, but only
324 	 * decremented and read from the thread that owns this
325 	 * qpair.
326 	 */
327 	uint32_t				refcnt;
328 };
329 
330 struct spdk_nvmf_rdma_poller {
331 	struct spdk_nvmf_rdma_device		*device;
332 	struct spdk_nvmf_rdma_poll_group	*group;
333 
334 	struct ibv_cq				*cq;
335 
336 	TAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs;
337 
338 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
339 };
340 
341 struct spdk_nvmf_rdma_poll_group {
342 	struct spdk_nvmf_transport_poll_group	group;
343 
344 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)	pollers;
345 };
346 
347 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
348 struct spdk_nvmf_rdma_device {
349 	struct ibv_device_attr			attr;
350 	struct ibv_context			*context;
351 
352 	struct spdk_mem_map			*map;
353 	struct ibv_pd				*pd;
354 
355 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
356 };
357 
358 struct spdk_nvmf_rdma_port {
359 	struct spdk_nvme_transport_id		trid;
360 	struct rdma_cm_id			*id;
361 	struct spdk_nvmf_rdma_device		*device;
362 	uint32_t				ref;
363 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
364 };
365 
366 struct spdk_nvmf_rdma_transport {
367 	struct spdk_nvmf_transport	transport;
368 
369 	struct rdma_event_channel	*event_channel;
370 
371 	struct spdk_mempool		*data_buf_pool;
372 
373 	pthread_mutex_t			lock;
374 
375 	/* fields used to poll RDMA/IB events */
376 	nfds_t			npoll_fds;
377 	struct pollfd		*poll_fds;
378 
379 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
380 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
381 };
382 
383 struct spdk_nvmf_rdma_mgmt_channel {
384 	/* Requests that are waiting to obtain a data buffer */
385 	TAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_data_buf_queue;
386 };
387 
388 static inline void
389 spdk_nvmf_rdma_qpair_inc_refcnt(struct spdk_nvmf_rdma_qpair *rqpair)
390 {
391 	__sync_fetch_and_add(&rqpair->refcnt, 1);
392 }
393 
394 static inline uint32_t
395 spdk_nvmf_rdma_qpair_dec_refcnt(struct spdk_nvmf_rdma_qpair *rqpair)
396 {
397 	uint32_t old_refcnt, new_refcnt;
398 
399 	do {
400 		old_refcnt = rqpair->refcnt;
401 		assert(old_refcnt > 0);
402 		new_refcnt = old_refcnt - 1;
403 	} while (__sync_bool_compare_and_swap(&rqpair->refcnt, old_refcnt, new_refcnt) == false);
404 
405 	return new_refcnt;
406 }
407 
408 static enum ibv_qp_state
409 spdk_nvmf_rdma_update_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair) {
410 	enum ibv_qp_state old_state, new_state;
411 	int rc;
412 
413 	/* All the attributes needed for recovery */
414 	static int spdk_nvmf_ibv_attr_mask =
415 	IBV_QP_STATE |
416 	IBV_QP_PKEY_INDEX |
417 	IBV_QP_PORT |
418 	IBV_QP_ACCESS_FLAGS |
419 	IBV_QP_AV |
420 	IBV_QP_PATH_MTU |
421 	IBV_QP_DEST_QPN |
422 	IBV_QP_RQ_PSN |
423 	IBV_QP_MAX_DEST_RD_ATOMIC |
424 	IBV_QP_MIN_RNR_TIMER |
425 	IBV_QP_SQ_PSN |
426 	IBV_QP_TIMEOUT |
427 	IBV_QP_RETRY_CNT |
428 	IBV_QP_RNR_RETRY |
429 	IBV_QP_MAX_QP_RD_ATOMIC;
430 
431 	old_state = rqpair->ibv_attr.qp_state;
432 	rc = ibv_query_qp(rqpair->cm_id->qp, &rqpair->ibv_attr,
433 			  spdk_nvmf_ibv_attr_mask, &rqpair->ibv_init_attr);
434 
435 	if (rc)
436 	{
437 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
438 		assert(false);
439 	}
440 
441 	new_state = rqpair->ibv_attr.qp_state;
442 	if (old_state != new_state)
443 	{
444 		spdk_trace_record(TRACE_RDMA_QP_STATE_CHANGE, 0, 0,
445 				  (uintptr_t)rqpair->cm_id, new_state);
446 	}
447 	return new_state;
448 }
449 
450 static const char *str_ibv_qp_state[] = {
451 	"IBV_QPS_RESET",
452 	"IBV_QPS_INIT",
453 	"IBV_QPS_RTR",
454 	"IBV_QPS_RTS",
455 	"IBV_QPS_SQD",
456 	"IBV_QPS_SQE",
457 	"IBV_QPS_ERR"
458 };
459 
460 static int
461 spdk_nvmf_rdma_set_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair,
462 			     enum ibv_qp_state new_state)
463 {
464 	int rc;
465 	enum ibv_qp_state state;
466 	static int attr_mask_rc[] = {
467 		[IBV_QPS_RESET] = IBV_QP_STATE,
468 		[IBV_QPS_INIT] = (IBV_QP_STATE |
469 				  IBV_QP_PKEY_INDEX |
470 				  IBV_QP_PORT |
471 				  IBV_QP_ACCESS_FLAGS),
472 		[IBV_QPS_RTR] = (IBV_QP_STATE |
473 				 IBV_QP_AV |
474 				 IBV_QP_PATH_MTU |
475 				 IBV_QP_DEST_QPN |
476 				 IBV_QP_RQ_PSN |
477 				 IBV_QP_MAX_DEST_RD_ATOMIC |
478 				 IBV_QP_MIN_RNR_TIMER),
479 		[IBV_QPS_RTS] = (IBV_QP_STATE |
480 				 IBV_QP_SQ_PSN |
481 				 IBV_QP_TIMEOUT |
482 				 IBV_QP_RETRY_CNT |
483 				 IBV_QP_RNR_RETRY |
484 				 IBV_QP_MAX_QP_RD_ATOMIC),
485 		[IBV_QPS_SQD] = IBV_QP_STATE,
486 		[IBV_QPS_SQE] = IBV_QP_STATE,
487 		[IBV_QPS_ERR] = IBV_QP_STATE,
488 	};
489 
490 	switch (new_state) {
491 	case IBV_QPS_RESET:
492 	case IBV_QPS_INIT:
493 	case IBV_QPS_RTR:
494 	case IBV_QPS_RTS:
495 	case IBV_QPS_SQD:
496 	case IBV_QPS_SQE:
497 	case IBV_QPS_ERR:
498 		break;
499 	default:
500 		SPDK_ERRLOG("QP#%d: bad state requested: %u\n",
501 			    rqpair->qpair.qid, new_state);
502 		return -1;
503 	}
504 	rqpair->ibv_attr.cur_qp_state = rqpair->ibv_attr.qp_state;
505 	rqpair->ibv_attr.qp_state = new_state;
506 	rqpair->ibv_attr.ah_attr.port_num = rqpair->ibv_attr.port_num;
507 
508 	rc = ibv_modify_qp(rqpair->cm_id->qp, &rqpair->ibv_attr,
509 			   attr_mask_rc[new_state]);
510 
511 	if (rc) {
512 		SPDK_ERRLOG("QP#%d: failed to set state to: %s, %d (%s)\n",
513 			    rqpair->qpair.qid, str_ibv_qp_state[new_state], errno, strerror(errno));
514 		return rc;
515 	}
516 
517 	state = spdk_nvmf_rdma_update_ibv_state(rqpair);
518 
519 	if (state != new_state) {
520 		SPDK_ERRLOG("QP#%d: expected state: %s, actual state: %s\n",
521 			    rqpair->qpair.qid, str_ibv_qp_state[new_state],
522 			    str_ibv_qp_state[state]);
523 		return -1;
524 	}
525 	SPDK_NOTICELOG("IBV QP#%u changed to: %s\n", rqpair->qpair.qid,
526 		       str_ibv_qp_state[state]);
527 	return 0;
528 }
529 
530 static void
531 spdk_nvmf_rdma_request_set_state(struct spdk_nvmf_rdma_request *rdma_req,
532 				 enum spdk_nvmf_rdma_request_state state)
533 {
534 	struct spdk_nvmf_qpair		*qpair;
535 	struct spdk_nvmf_rdma_qpair	*rqpair;
536 
537 	qpair = rdma_req->req.qpair;
538 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
539 
540 	TAILQ_REMOVE(&rqpair->state_queue[rdma_req->state], rdma_req, state_link);
541 	rqpair->state_cntr[rdma_req->state]--;
542 
543 	rdma_req->state = state;
544 
545 	TAILQ_INSERT_TAIL(&rqpair->state_queue[rdma_req->state], rdma_req, state_link);
546 	rqpair->state_cntr[rdma_req->state]++;
547 }
548 
549 static int
550 spdk_nvmf_rdma_mgmt_channel_create(void *io_device, void *ctx_buf)
551 {
552 	struct spdk_nvmf_rdma_mgmt_channel *ch = ctx_buf;
553 
554 	TAILQ_INIT(&ch->pending_data_buf_queue);
555 	return 0;
556 }
557 
558 static void
559 spdk_nvmf_rdma_mgmt_channel_destroy(void *io_device, void *ctx_buf)
560 {
561 	struct spdk_nvmf_rdma_mgmt_channel *ch = ctx_buf;
562 
563 	if (!TAILQ_EMPTY(&ch->pending_data_buf_queue)) {
564 		SPDK_ERRLOG("Pending I/O list wasn't empty on channel destruction\n");
565 	}
566 }
567 
568 static int
569 spdk_nvmf_rdma_cur_rw_depth(struct spdk_nvmf_rdma_qpair *rqpair)
570 {
571 	return rqpair->state_cntr[RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER] +
572 	       rqpair->state_cntr[RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST];
573 }
574 
575 static int
576 spdk_nvmf_rdma_cur_queue_depth(struct spdk_nvmf_rdma_qpair *rqpair)
577 {
578 	return rqpair->max_queue_depth -
579 	       rqpair->state_cntr[RDMA_REQUEST_STATE_FREE];
580 }
581 
582 static void
583 spdk_nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
584 {
585 	int qd;
586 
587 	if (rqpair->refcnt == 0) {
588 		return;
589 	}
590 
591 	spdk_trace_record(TRACE_RDMA_QP_DESTROY, 0, 0, (uintptr_t)rqpair->cm_id, 0);
592 
593 	qd = spdk_nvmf_rdma_cur_queue_depth(rqpair);
594 	if (qd != 0) {
595 		SPDK_WARNLOG("Destroying qpair when queue depth is %d\n", qd);
596 	}
597 
598 	if (rqpair->poller) {
599 		TAILQ_REMOVE(&rqpair->poller->qpairs, rqpair, link);
600 	}
601 
602 	if (rqpair->cmds_mr) {
603 		ibv_dereg_mr(rqpair->cmds_mr);
604 	}
605 
606 	if (rqpair->cpls_mr) {
607 		ibv_dereg_mr(rqpair->cpls_mr);
608 	}
609 
610 	if (rqpair->bufs_mr) {
611 		ibv_dereg_mr(rqpair->bufs_mr);
612 	}
613 
614 	if (rqpair->cm_id) {
615 		rdma_destroy_qp(rqpair->cm_id);
616 		rdma_destroy_id(rqpair->cm_id);
617 	}
618 
619 	if (rqpair->mgmt_channel) {
620 		spdk_put_io_channel(rqpair->mgmt_channel);
621 	}
622 
623 	/* Free all memory */
624 	spdk_dma_free(rqpair->cmds);
625 	spdk_dma_free(rqpair->cpls);
626 	spdk_dma_free(rqpair->bufs);
627 	free(rqpair->reqs);
628 	free(rqpair->recvs);
629 	free(rqpair);
630 }
631 
632 static int
633 spdk_nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
634 {
635 	struct spdk_nvmf_rdma_transport *rtransport;
636 	struct spdk_nvmf_rdma_qpair	*rqpair;
637 	int				rc, i;
638 	struct spdk_nvmf_rdma_recv	*rdma_recv;
639 	struct spdk_nvmf_rdma_request	*rdma_req;
640 	struct spdk_nvmf_transport      *transport;
641 
642 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
643 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
644 	transport = &rtransport->transport;
645 
646 	memset(&rqpair->ibv_init_attr, 0, sizeof(struct ibv_qp_init_attr));
647 	rqpair->ibv_init_attr.qp_context	= rqpair;
648 	rqpair->ibv_init_attr.qp_type		= IBV_QPT_RC;
649 	rqpair->ibv_init_attr.send_cq		= rqpair->poller->cq;
650 	rqpair->ibv_init_attr.recv_cq		= rqpair->poller->cq;
651 	rqpair->ibv_init_attr.cap.max_send_wr	= rqpair->max_queue_depth *
652 			2 + 1; /* SEND, READ, and WRITE operations + dummy drain WR */
653 	rqpair->ibv_init_attr.cap.max_recv_wr	= rqpair->max_queue_depth +
654 			1; /* RECV operations + dummy drain WR */
655 	rqpair->ibv_init_attr.cap.max_send_sge	= rqpair->max_sge;
656 	rqpair->ibv_init_attr.cap.max_recv_sge	= NVMF_DEFAULT_RX_SGE;
657 
658 	rc = rdma_create_qp(rqpair->cm_id, rqpair->port->device->pd, &rqpair->ibv_init_attr);
659 	if (rc) {
660 		SPDK_ERRLOG("rdma_create_qp failed: errno %d: %s\n", errno, spdk_strerror(errno));
661 		rdma_destroy_id(rqpair->cm_id);
662 		rqpair->cm_id = NULL;
663 		spdk_nvmf_rdma_qpair_destroy(rqpair);
664 		return -1;
665 	}
666 
667 	spdk_trace_record(TRACE_RDMA_QP_CREATE, 0, 0, (uintptr_t)rqpair->cm_id, 0);
668 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "New RDMA Connection: %p\n", qpair);
669 
670 	rqpair->reqs = calloc(rqpair->max_queue_depth, sizeof(*rqpair->reqs));
671 	rqpair->recvs = calloc(rqpair->max_queue_depth, sizeof(*rqpair->recvs));
672 	rqpair->cmds = spdk_dma_zmalloc(rqpair->max_queue_depth * sizeof(*rqpair->cmds),
673 					0x1000, NULL);
674 	rqpair->cpls = spdk_dma_zmalloc(rqpair->max_queue_depth * sizeof(*rqpair->cpls),
675 					0x1000, NULL);
676 
677 
678 	if (transport->opts.in_capsule_data_size > 0) {
679 		rqpair->bufs = spdk_dma_zmalloc(rqpair->max_queue_depth *
680 						transport->opts.in_capsule_data_size,
681 						0x1000, NULL);
682 	}
683 
684 	if (!rqpair->reqs || !rqpair->recvs || !rqpair->cmds ||
685 	    !rqpair->cpls || (transport->opts.in_capsule_data_size && !rqpair->bufs)) {
686 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
687 		spdk_nvmf_rdma_qpair_destroy(rqpair);
688 		return -1;
689 	}
690 
691 	rqpair->cmds_mr = ibv_reg_mr(rqpair->cm_id->pd, rqpair->cmds,
692 				     rqpair->max_queue_depth * sizeof(*rqpair->cmds),
693 				     IBV_ACCESS_LOCAL_WRITE);
694 	rqpair->cpls_mr = ibv_reg_mr(rqpair->cm_id->pd, rqpair->cpls,
695 				     rqpair->max_queue_depth * sizeof(*rqpair->cpls),
696 				     0);
697 
698 	if (transport->opts.in_capsule_data_size) {
699 		rqpair->bufs_mr = ibv_reg_mr(rqpair->cm_id->pd, rqpair->bufs,
700 					     rqpair->max_queue_depth *
701 					     transport->opts.in_capsule_data_size,
702 					     IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
703 	}
704 
705 	if (!rqpair->cmds_mr || !rqpair->cpls_mr || (transport->opts.in_capsule_data_size &&
706 			!rqpair->bufs_mr)) {
707 		SPDK_ERRLOG("Unable to register required memory for RDMA queue.\n");
708 		spdk_nvmf_rdma_qpair_destroy(rqpair);
709 		return -1;
710 	}
711 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Command Array: %p Length: %lx LKey: %x\n",
712 		      rqpair->cmds, rqpair->max_queue_depth * sizeof(*rqpair->cmds), rqpair->cmds_mr->lkey);
713 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Completion Array: %p Length: %lx LKey: %x\n",
714 		      rqpair->cpls, rqpair->max_queue_depth * sizeof(*rqpair->cpls), rqpair->cpls_mr->lkey);
715 	if (rqpair->bufs && rqpair->bufs_mr) {
716 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "In Capsule Data Array: %p Length: %x LKey: %x\n",
717 			      rqpair->bufs, rqpair->max_queue_depth *
718 			      transport->opts.in_capsule_data_size, rqpair->bufs_mr->lkey);
719 	}
720 
721 	/* Initialise request state queues and counters of the queue pair */
722 	for (i = RDMA_REQUEST_STATE_FREE; i < RDMA_REQUEST_NUM_STATES; i++) {
723 		TAILQ_INIT(&rqpair->state_queue[i]);
724 		rqpair->state_cntr[i] = 0;
725 	}
726 
727 	for (i = 0; i < rqpair->max_queue_depth; i++) {
728 		struct ibv_recv_wr *bad_wr = NULL;
729 
730 		rdma_recv = &rqpair->recvs[i];
731 		rdma_recv->qpair = rqpair;
732 
733 		/* Set up memory to receive commands */
734 		if (rqpair->bufs) {
735 			rdma_recv->buf = (void *)((uintptr_t)rqpair->bufs + (i *
736 						  transport->opts.in_capsule_data_size));
737 		}
738 
739 		rdma_recv->rdma_wr.type = RDMA_WR_TYPE_RECV;
740 
741 		rdma_recv->sgl[0].addr = (uintptr_t)&rqpair->cmds[i];
742 		rdma_recv->sgl[0].length = sizeof(rqpair->cmds[i]);
743 		rdma_recv->sgl[0].lkey = rqpair->cmds_mr->lkey;
744 		rdma_recv->wr.num_sge = 1;
745 
746 		if (rdma_recv->buf && rqpair->bufs_mr) {
747 			rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
748 			rdma_recv->sgl[1].length = transport->opts.in_capsule_data_size;
749 			rdma_recv->sgl[1].lkey = rqpair->bufs_mr->lkey;
750 			rdma_recv->wr.num_sge++;
751 		}
752 
753 		rdma_recv->wr.wr_id = (uintptr_t)&rdma_recv->rdma_wr;
754 		rdma_recv->wr.sg_list = rdma_recv->sgl;
755 
756 		rc = ibv_post_recv(rqpair->cm_id->qp, &rdma_recv->wr, &bad_wr);
757 		if (rc) {
758 			SPDK_ERRLOG("Unable to post capsule for RDMA RECV\n");
759 			spdk_nvmf_rdma_qpair_destroy(rqpair);
760 			return -1;
761 		}
762 	}
763 
764 	for (i = 0; i < rqpair->max_queue_depth; i++) {
765 		rdma_req = &rqpair->reqs[i];
766 
767 		rdma_req->req.qpair = &rqpair->qpair;
768 		rdma_req->req.cmd = NULL;
769 
770 		/* Set up memory to send responses */
771 		rdma_req->req.rsp = &rqpair->cpls[i];
772 
773 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&rqpair->cpls[i];
774 		rdma_req->rsp.sgl[0].length = sizeof(rqpair->cpls[i]);
775 		rdma_req->rsp.sgl[0].lkey = rqpair->cpls_mr->lkey;
776 
777 		rdma_req->rsp.rdma_wr.type = RDMA_WR_TYPE_SEND;
778 		rdma_req->rsp.wr.wr_id = (uintptr_t)&rdma_req->rsp.rdma_wr;
779 		rdma_req->rsp.wr.next = NULL;
780 		rdma_req->rsp.wr.opcode = IBV_WR_SEND;
781 		rdma_req->rsp.wr.send_flags = IBV_SEND_SIGNALED;
782 		rdma_req->rsp.wr.sg_list = rdma_req->rsp.sgl;
783 		rdma_req->rsp.wr.num_sge = SPDK_COUNTOF(rdma_req->rsp.sgl);
784 
785 		/* Set up memory for data buffers */
786 		rdma_req->data.rdma_wr.type = RDMA_WR_TYPE_DATA;
787 		rdma_req->data.wr.wr_id = (uintptr_t)&rdma_req->data.rdma_wr;
788 		rdma_req->data.wr.next = NULL;
789 		rdma_req->data.wr.send_flags = IBV_SEND_SIGNALED;
790 		rdma_req->data.wr.sg_list = rdma_req->data.sgl;
791 		rdma_req->data.wr.num_sge = SPDK_COUNTOF(rdma_req->data.sgl);
792 
793 		/* Initialize request state to FREE */
794 		rdma_req->state = RDMA_REQUEST_STATE_FREE;
795 		TAILQ_INSERT_TAIL(&rqpair->state_queue[rdma_req->state], rdma_req, state_link);
796 		rqpair->state_cntr[rdma_req->state]++;
797 	}
798 
799 	return 0;
800 }
801 
802 static int
803 request_transfer_in(struct spdk_nvmf_request *req)
804 {
805 	int				rc;
806 	struct spdk_nvmf_rdma_request	*rdma_req;
807 	struct spdk_nvmf_qpair		*qpair;
808 	struct spdk_nvmf_rdma_qpair	*rqpair;
809 	struct ibv_send_wr		*bad_wr = NULL;
810 
811 	qpair = req->qpair;
812 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
813 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
814 
815 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
816 
817 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA READ POSTED. Request: %p Connection: %p\n", req, qpair);
818 
819 	rdma_req->data.wr.opcode = IBV_WR_RDMA_READ;
820 	rdma_req->data.wr.next = NULL;
821 	rc = ibv_post_send(rqpair->cm_id->qp, &rdma_req->data.wr, &bad_wr);
822 	if (rc) {
823 		SPDK_ERRLOG("Unable to transfer data from host to target\n");
824 		return -1;
825 	}
826 	return 0;
827 }
828 
829 static int
830 request_transfer_out(struct spdk_nvmf_request *req, int *data_posted)
831 {
832 	int				rc;
833 	struct spdk_nvmf_rdma_request	*rdma_req;
834 	struct spdk_nvmf_qpair		*qpair;
835 	struct spdk_nvmf_rdma_qpair	*rqpair;
836 	struct spdk_nvme_cpl		*rsp;
837 	struct ibv_recv_wr		*bad_recv_wr = NULL;
838 	struct ibv_send_wr		*send_wr, *bad_send_wr = NULL;
839 
840 	*data_posted = 0;
841 	qpair = req->qpair;
842 	rsp = &req->rsp->nvme_cpl;
843 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
844 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
845 
846 	/* Advance our sq_head pointer */
847 	if (qpair->sq_head == qpair->sq_head_max) {
848 		qpair->sq_head = 0;
849 	} else {
850 		qpair->sq_head++;
851 	}
852 	rsp->sqhd = qpair->sq_head;
853 
854 	/* Post the capsule to the recv buffer */
855 	assert(rdma_req->recv != NULL);
856 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA RECV POSTED. Recv: %p Connection: %p\n", rdma_req->recv,
857 		      rqpair);
858 	rc = ibv_post_recv(rqpair->cm_id->qp, &rdma_req->recv->wr, &bad_recv_wr);
859 	if (rc) {
860 		SPDK_ERRLOG("Unable to re-post rx descriptor\n");
861 		return rc;
862 	}
863 	rdma_req->recv = NULL;
864 
865 	/* Build the response which consists of an optional
866 	 * RDMA WRITE to transfer data, plus an RDMA SEND
867 	 * containing the response.
868 	 */
869 	send_wr = &rdma_req->rsp.wr;
870 
871 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
872 	    req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
873 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA WRITE POSTED. Request: %p Connection: %p\n", req, qpair);
874 
875 		rdma_req->data.wr.opcode = IBV_WR_RDMA_WRITE;
876 
877 		rdma_req->data.wr.next = send_wr;
878 		*data_posted = 1;
879 		send_wr = &rdma_req->data.wr;
880 	}
881 
882 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA SEND POSTED. Request: %p Connection: %p\n", req, qpair);
883 
884 	/* Send the completion */
885 	rc = ibv_post_send(rqpair->cm_id->qp, send_wr, &bad_send_wr);
886 	if (rc) {
887 		SPDK_ERRLOG("Unable to send response capsule\n");
888 	}
889 
890 	return rc;
891 }
892 
893 static int
894 spdk_nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
895 {
896 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
897 	struct rdma_conn_param				ctrlr_event_data = {};
898 	int						rc;
899 
900 	accept_data.recfmt = 0;
901 	accept_data.crqsize = rqpair->max_queue_depth;
902 
903 	ctrlr_event_data.private_data = &accept_data;
904 	ctrlr_event_data.private_data_len = sizeof(accept_data);
905 	if (id->ps == RDMA_PS_TCP) {
906 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
907 		ctrlr_event_data.initiator_depth = rqpair->max_rw_depth;
908 	}
909 
910 	rc = rdma_accept(id, &ctrlr_event_data);
911 	if (rc) {
912 		SPDK_ERRLOG("Error %d on rdma_accept\n", errno);
913 	} else {
914 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Sent back the accept\n");
915 	}
916 
917 	return rc;
918 }
919 
920 static void
921 spdk_nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
922 {
923 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
924 
925 	rej_data.recfmt = 0;
926 	rej_data.sts = error;
927 
928 	rdma_reject(id, &rej_data, sizeof(rej_data));
929 }
930 
931 static int
932 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event,
933 		  new_qpair_fn cb_fn)
934 {
935 	struct spdk_nvmf_rdma_transport *rtransport;
936 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
937 	struct spdk_nvmf_rdma_port	*port;
938 	struct rdma_conn_param		*rdma_param = NULL;
939 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
940 	uint16_t			max_queue_depth;
941 	uint16_t			max_rw_depth;
942 
943 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
944 
945 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
946 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
947 
948 	rdma_param = &event->param.conn;
949 	if (rdma_param->private_data == NULL ||
950 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
951 		SPDK_ERRLOG("connect request: no private data provided\n");
952 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
953 		return -1;
954 	}
955 
956 	private_data = rdma_param->private_data;
957 	if (private_data->recfmt != 0) {
958 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
959 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
960 		return -1;
961 	}
962 
963 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Connect Recv on fabric intf name %s, dev_name %s\n",
964 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
965 
966 	port = event->listen_id->context;
967 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
968 		      event->listen_id, event->listen_id->verbs, port);
969 
970 	/* Figure out the supported queue depth. This is a multi-step process
971 	 * that takes into account hardware maximums, host provided values,
972 	 * and our target's internal memory limits */
973 
974 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Calculating Queue Depth\n");
975 
976 	/* Start with the maximum queue depth allowed by the target */
977 	max_queue_depth = rtransport->transport.opts.max_queue_depth;
978 	max_rw_depth = rtransport->transport.opts.max_queue_depth;
979 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Target Max Queue Depth: %d\n",
980 		      rtransport->transport.opts.max_queue_depth);
981 
982 	/* Next check the local NIC's hardware limitations */
983 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
984 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
985 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
986 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
987 	max_rw_depth = spdk_min(max_rw_depth, port->device->attr.max_qp_rd_atom);
988 
989 	/* Next check the remote NIC's hardware limitations */
990 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
991 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
992 		      rdma_param->initiator_depth, rdma_param->responder_resources);
993 	if (rdma_param->initiator_depth > 0) {
994 		max_rw_depth = spdk_min(max_rw_depth, rdma_param->initiator_depth);
995 	}
996 
997 	/* Finally check for the host software requested values, which are
998 	 * optional. */
999 	if (rdma_param->private_data != NULL &&
1000 	    rdma_param->private_data_len >= sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1001 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1002 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Send Queue Size: %d\n", private_data->hsqsize);
1003 		max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
1004 		max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
1005 	}
1006 
1007 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
1008 		      max_queue_depth, max_rw_depth);
1009 
1010 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
1011 	if (rqpair == NULL) {
1012 		SPDK_ERRLOG("Could not allocate new connection.\n");
1013 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1014 		return -1;
1015 	}
1016 
1017 	rqpair->port = port;
1018 	rqpair->max_queue_depth = max_queue_depth;
1019 	rqpair->max_rw_depth = max_rw_depth;
1020 	rqpair->cm_id = event->id;
1021 	rqpair->listen_id = event->listen_id;
1022 	rqpair->qpair.transport = transport;
1023 	rqpair->max_sge = spdk_min(port->device->attr.max_sge, SPDK_NVMF_MAX_SGL_ENTRIES);
1024 	TAILQ_INIT(&rqpair->incoming_queue);
1025 	event->id->context = &rqpair->qpair;
1026 
1027 	cb_fn(&rqpair->qpair);
1028 
1029 	return 0;
1030 }
1031 
1032 static int
1033 spdk_nvmf_rdma_mem_notify(void *cb_ctx, struct spdk_mem_map *map,
1034 			  enum spdk_mem_map_notify_action action,
1035 			  void *vaddr, size_t size)
1036 {
1037 	struct spdk_nvmf_rdma_device *device = cb_ctx;
1038 	struct ibv_pd *pd = device->pd;
1039 	struct ibv_mr *mr;
1040 
1041 	switch (action) {
1042 	case SPDK_MEM_MAP_NOTIFY_REGISTER:
1043 		mr = ibv_reg_mr(pd, vaddr, size,
1044 				IBV_ACCESS_LOCAL_WRITE |
1045 				IBV_ACCESS_REMOTE_READ |
1046 				IBV_ACCESS_REMOTE_WRITE);
1047 		if (mr == NULL) {
1048 			SPDK_ERRLOG("ibv_reg_mr() failed\n");
1049 			return -1;
1050 		} else {
1051 			spdk_mem_map_set_translation(map, (uint64_t)vaddr, size, (uint64_t)mr);
1052 		}
1053 		break;
1054 	case SPDK_MEM_MAP_NOTIFY_UNREGISTER:
1055 		mr = (struct ibv_mr *)spdk_mem_map_translate(map, (uint64_t)vaddr, NULL);
1056 		spdk_mem_map_clear_translation(map, (uint64_t)vaddr, size);
1057 		if (mr) {
1058 			ibv_dereg_mr(mr);
1059 		}
1060 		break;
1061 	}
1062 
1063 	return 0;
1064 }
1065 
1066 typedef enum spdk_nvme_data_transfer spdk_nvme_data_transfer_t;
1067 
1068 static spdk_nvme_data_transfer_t
1069 spdk_nvmf_rdma_request_get_xfer(struct spdk_nvmf_rdma_request *rdma_req)
1070 {
1071 	enum spdk_nvme_data_transfer xfer;
1072 	struct spdk_nvme_cmd *cmd = &rdma_req->req.cmd->nvme_cmd;
1073 	struct spdk_nvme_sgl_descriptor *sgl = &cmd->dptr.sgl1;
1074 
1075 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1076 	rdma_req->rsp.wr.opcode = IBV_WR_SEND;
1077 	rdma_req->rsp.wr.imm_data = 0;
1078 #endif
1079 
1080 	/* Figure out data transfer direction */
1081 	if (cmd->opc == SPDK_NVME_OPC_FABRIC) {
1082 		xfer = spdk_nvme_opc_get_data_transfer(rdma_req->req.cmd->nvmf_cmd.fctype);
1083 	} else {
1084 		xfer = spdk_nvme_opc_get_data_transfer(cmd->opc);
1085 
1086 		/* Some admin commands are special cases */
1087 		if ((rdma_req->req.qpair->qid == 0) &&
1088 		    ((cmd->opc == SPDK_NVME_OPC_GET_FEATURES) ||
1089 		     (cmd->opc == SPDK_NVME_OPC_SET_FEATURES))) {
1090 			switch (cmd->cdw10 & 0xff) {
1091 			case SPDK_NVME_FEAT_LBA_RANGE_TYPE:
1092 			case SPDK_NVME_FEAT_AUTONOMOUS_POWER_STATE_TRANSITION:
1093 			case SPDK_NVME_FEAT_HOST_IDENTIFIER:
1094 				break;
1095 			default:
1096 				xfer = SPDK_NVME_DATA_NONE;
1097 			}
1098 		}
1099 	}
1100 
1101 	if (xfer == SPDK_NVME_DATA_NONE) {
1102 		return xfer;
1103 	}
1104 
1105 	/* Even for commands that may transfer data, they could have specified 0 length.
1106 	 * We want those to show up with xfer SPDK_NVME_DATA_NONE.
1107 	 */
1108 	switch (sgl->generic.type) {
1109 	case SPDK_NVME_SGL_TYPE_DATA_BLOCK:
1110 	case SPDK_NVME_SGL_TYPE_BIT_BUCKET:
1111 	case SPDK_NVME_SGL_TYPE_SEGMENT:
1112 	case SPDK_NVME_SGL_TYPE_LAST_SEGMENT:
1113 	case SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK:
1114 		if (sgl->unkeyed.length == 0) {
1115 			xfer = SPDK_NVME_DATA_NONE;
1116 		}
1117 		break;
1118 	case SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK:
1119 		if (sgl->keyed.length == 0) {
1120 			xfer = SPDK_NVME_DATA_NONE;
1121 		}
1122 		break;
1123 	}
1124 
1125 	return xfer;
1126 }
1127 
1128 static int
1129 spdk_nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1130 				 struct spdk_nvmf_rdma_device *device,
1131 				 struct spdk_nvmf_rdma_request *rdma_req)
1132 {
1133 	void		*buf = NULL;
1134 	uint32_t	length = rdma_req->req.length;
1135 	uint32_t	i = 0;
1136 
1137 	rdma_req->req.iovcnt = 0;
1138 	while (length) {
1139 		buf = spdk_mempool_get(rtransport->data_buf_pool);
1140 		if (!buf) {
1141 			goto nomem;
1142 		}
1143 
1144 		rdma_req->req.iov[i].iov_base = (void *)((uintptr_t)(buf + NVMF_DATA_BUFFER_MASK) &
1145 						~NVMF_DATA_BUFFER_MASK);
1146 		rdma_req->req.iov[i].iov_len  = spdk_min(length, rtransport->transport.opts.io_unit_size);
1147 		rdma_req->req.iovcnt++;
1148 		rdma_req->data.buffers[i] = buf;
1149 		rdma_req->data.wr.sg_list[i].addr = (uintptr_t)(rdma_req->req.iov[i].iov_base);
1150 		rdma_req->data.wr.sg_list[i].length = rdma_req->req.iov[i].iov_len;
1151 		rdma_req->data.wr.sg_list[i].lkey = ((struct ibv_mr *)spdk_mem_map_translate(device->map,
1152 						     (uint64_t)buf, NULL))->lkey;
1153 
1154 		length -= rdma_req->req.iov[i].iov_len;
1155 		i++;
1156 	}
1157 
1158 	rdma_req->data_from_pool = true;
1159 
1160 	return 0;
1161 
1162 nomem:
1163 	while (i) {
1164 		i--;
1165 		spdk_mempool_put(rtransport->data_buf_pool, rdma_req->req.iov[i].iov_base);
1166 		rdma_req->req.iov[i].iov_base = NULL;
1167 		rdma_req->req.iov[i].iov_len = 0;
1168 
1169 		rdma_req->data.wr.sg_list[i].addr = 0;
1170 		rdma_req->data.wr.sg_list[i].length = 0;
1171 		rdma_req->data.wr.sg_list[i].lkey = 0;
1172 	}
1173 	rdma_req->req.iovcnt = 0;
1174 	return -ENOMEM;
1175 }
1176 
1177 static int
1178 spdk_nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1179 				 struct spdk_nvmf_rdma_device *device,
1180 				 struct spdk_nvmf_rdma_request *rdma_req)
1181 {
1182 	struct spdk_nvme_cmd			*cmd;
1183 	struct spdk_nvme_cpl			*rsp;
1184 	struct spdk_nvme_sgl_descriptor		*sgl;
1185 
1186 	cmd = &rdma_req->req.cmd->nvme_cmd;
1187 	rsp = &rdma_req->req.rsp->nvme_cpl;
1188 	sgl = &cmd->dptr.sgl1;
1189 
1190 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1191 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1192 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1193 		if (sgl->keyed.length > rtransport->transport.opts.max_io_size) {
1194 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1195 				    sgl->keyed.length, rtransport->transport.opts.max_io_size);
1196 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1197 			return -1;
1198 		}
1199 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1200 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1201 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1202 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1203 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1204 			}
1205 		}
1206 #endif
1207 
1208 		/* fill request length and populate iovs */
1209 		rdma_req->req.length = sgl->keyed.length;
1210 
1211 		if (spdk_nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req) < 0) {
1212 			/* No available buffers. Queue this request up. */
1213 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1214 			return 0;
1215 		}
1216 
1217 		/* backward compatible */
1218 		rdma_req->req.data = rdma_req->req.iov[0].iov_base;
1219 
1220 		/* rdma wr specifics */
1221 		rdma_req->data.wr.num_sge = rdma_req->req.iovcnt;
1222 		rdma_req->data.wr.wr.rdma.rkey = sgl->keyed.key;
1223 		rdma_req->data.wr.wr.rdma.remote_addr = sgl->address;
1224 
1225 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1226 			      rdma_req->req.iovcnt);
1227 
1228 		return 0;
1229 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1230 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1231 		uint64_t offset = sgl->address;
1232 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1233 
1234 		SPDK_DEBUGLOG(SPDK_LOG_NVMF, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1235 			      offset, sgl->unkeyed.length);
1236 
1237 		if (offset > max_len) {
1238 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1239 				    offset, max_len);
1240 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1241 			return -1;
1242 		}
1243 		max_len -= (uint32_t)offset;
1244 
1245 		if (sgl->unkeyed.length > max_len) {
1246 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1247 				    sgl->unkeyed.length, max_len);
1248 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1249 			return -1;
1250 		}
1251 
1252 		rdma_req->req.data = rdma_req->recv->buf + offset;
1253 		rdma_req->data_from_pool = false;
1254 		rdma_req->req.length = sgl->unkeyed.length;
1255 
1256 		rdma_req->req.iov[0].iov_base = rdma_req->req.data;
1257 		rdma_req->req.iov[0].iov_len = rdma_req->req.length;
1258 		rdma_req->req.iovcnt = 1;
1259 
1260 		return 0;
1261 	}
1262 
1263 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1264 		    sgl->generic.type, sgl->generic.subtype);
1265 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1266 	return -1;
1267 }
1268 
1269 static bool
1270 spdk_nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
1271 			       struct spdk_nvmf_rdma_request *rdma_req)
1272 {
1273 	struct spdk_nvmf_rdma_qpair	*rqpair;
1274 	struct spdk_nvmf_rdma_device	*device;
1275 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
1276 	int				rc;
1277 	struct spdk_nvmf_rdma_recv	*rdma_recv;
1278 	enum spdk_nvmf_rdma_request_state prev_state;
1279 	bool				progress = false;
1280 	int				data_posted;
1281 	int				cur_rdma_rw_depth;
1282 
1283 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1284 	device = rqpair->port->device;
1285 
1286 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
1287 
1288 	/* If the queue pair is in an error state, force the request to the completed state
1289 	 * to release resources. */
1290 	if (rqpair->ibv_attr.qp_state == IBV_QPS_ERR || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
1291 		if (rdma_req->state == RDMA_REQUEST_STATE_NEED_BUFFER) {
1292 			TAILQ_REMOVE(&rqpair->ch->pending_data_buf_queue, rdma_req, link);
1293 		}
1294 		spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_COMPLETED);
1295 	}
1296 
1297 	/* The loop here is to allow for several back-to-back state changes. */
1298 	do {
1299 		prev_state = rdma_req->state;
1300 
1301 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p entering state %d\n", rdma_req, prev_state);
1302 
1303 		switch (rdma_req->state) {
1304 		case RDMA_REQUEST_STATE_FREE:
1305 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
1306 			 * to escape this state. */
1307 			break;
1308 		case RDMA_REQUEST_STATE_NEW:
1309 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
1310 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1311 			rdma_recv = rdma_req->recv;
1312 
1313 			/* The first element of the SGL is the NVMe command */
1314 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
1315 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
1316 
1317 			TAILQ_REMOVE(&rqpair->incoming_queue, rdma_recv, link);
1318 
1319 			if (rqpair->ibv_attr.qp_state == IBV_QPS_ERR) {
1320 				spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_COMPLETED);
1321 				break;
1322 			}
1323 
1324 			/* The next state transition depends on the data transfer needs of this request. */
1325 			rdma_req->req.xfer = spdk_nvmf_rdma_request_get_xfer(rdma_req);
1326 
1327 			/* If no data to transfer, ready to execute. */
1328 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
1329 				spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_READY_TO_EXECUTE);
1330 				break;
1331 			}
1332 
1333 			spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_NEED_BUFFER);
1334 			TAILQ_INSERT_TAIL(&rqpair->ch->pending_data_buf_queue, rdma_req, link);
1335 			break;
1336 		case RDMA_REQUEST_STATE_NEED_BUFFER:
1337 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
1338 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1339 
1340 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
1341 
1342 			if (rdma_req != TAILQ_FIRST(&rqpair->ch->pending_data_buf_queue)) {
1343 				/* This request needs to wait in line to obtain a buffer */
1344 				break;
1345 			}
1346 
1347 			/* Try to get a data buffer */
1348 			rc = spdk_nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
1349 			if (rc < 0) {
1350 				TAILQ_REMOVE(&rqpair->ch->pending_data_buf_queue, rdma_req, link);
1351 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
1352 				spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_READY_TO_COMPLETE);
1353 				break;
1354 			}
1355 
1356 			if (!rdma_req->req.data) {
1357 				/* No buffers available. */
1358 				break;
1359 			}
1360 
1361 			TAILQ_REMOVE(&rqpair->ch->pending_data_buf_queue, rdma_req, link);
1362 
1363 			/* If data is transferring from host to controller and the data didn't
1364 			 * arrive using in capsule data, we need to do a transfer from the host.
1365 			 */
1366 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER && rdma_req->data_from_pool) {
1367 				spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_DATA_TRANSFER_PENDING);
1368 				break;
1369 			}
1370 
1371 			spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_READY_TO_EXECUTE);
1372 			break;
1373 		case RDMA_REQUEST_STATE_DATA_TRANSFER_PENDING:
1374 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_PENDING, 0, 0,
1375 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1376 
1377 			if (rdma_req != TAILQ_FIRST(&rqpair->state_queue[RDMA_REQUEST_STATE_DATA_TRANSFER_PENDING])) {
1378 				/* This request needs to wait in line to perform RDMA */
1379 				break;
1380 			}
1381 			cur_rdma_rw_depth = spdk_nvmf_rdma_cur_rw_depth(rqpair);
1382 
1383 			if (cur_rdma_rw_depth >= rqpair->max_rw_depth) {
1384 				/* R/W queue is full, need to wait */
1385 				break;
1386 			}
1387 
1388 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1389 				rc = request_transfer_in(&rdma_req->req);
1390 				if (!rc) {
1391 					spdk_nvmf_rdma_request_set_state(rdma_req,
1392 									 RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
1393 				} else {
1394 					rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
1395 					spdk_nvmf_rdma_request_set_state(rdma_req,
1396 									 RDMA_REQUEST_STATE_READY_TO_COMPLETE);
1397 				}
1398 			} else if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1399 				/* The data transfer will be kicked off from
1400 				 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
1401 				 */
1402 				spdk_nvmf_rdma_request_set_state(rdma_req,
1403 								 RDMA_REQUEST_STATE_READY_TO_COMPLETE);
1404 			} else {
1405 				SPDK_ERRLOG("Cannot perform data transfer, unknown state: %u\n",
1406 					    rdma_req->req.xfer);
1407 				assert(0);
1408 			}
1409 			break;
1410 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
1411 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
1412 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1413 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
1414 			 * to escape this state. */
1415 			break;
1416 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
1417 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
1418 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1419 			spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_EXECUTING);
1420 			spdk_nvmf_request_exec(&rdma_req->req);
1421 			break;
1422 		case RDMA_REQUEST_STATE_EXECUTING:
1423 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
1424 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1425 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
1426 			 * to escape this state. */
1427 			break;
1428 		case RDMA_REQUEST_STATE_EXECUTED:
1429 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
1430 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1431 			if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1432 				spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_DATA_TRANSFER_PENDING);
1433 			} else {
1434 				spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_READY_TO_COMPLETE);
1435 			}
1436 			break;
1437 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
1438 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
1439 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1440 			rc = request_transfer_out(&rdma_req->req, &data_posted);
1441 			assert(rc == 0); /* No good way to handle this currently */
1442 			if (rc) {
1443 				spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_COMPLETED);
1444 			} else {
1445 				spdk_nvmf_rdma_request_set_state(rdma_req,
1446 								 data_posted ?
1447 								 RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
1448 								 RDMA_REQUEST_STATE_COMPLETING);
1449 			}
1450 			break;
1451 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
1452 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
1453 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1454 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
1455 			 * to escape this state. */
1456 			break;
1457 		case RDMA_REQUEST_STATE_COMPLETING:
1458 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
1459 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1460 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
1461 			 * to escape this state. */
1462 			break;
1463 		case RDMA_REQUEST_STATE_COMPLETED:
1464 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
1465 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
1466 
1467 			if (rdma_req->data_from_pool) {
1468 				/* Put the buffer/s back in the pool */
1469 				for (uint32_t i = 0; i < rdma_req->req.iovcnt; i++) {
1470 					spdk_mempool_put(rtransport->data_buf_pool, rdma_req->data.buffers[i]);
1471 					rdma_req->req.iov[i].iov_base = NULL;
1472 					rdma_req->data.buffers[i] = NULL;
1473 				}
1474 				rdma_req->data_from_pool = false;
1475 			}
1476 			rdma_req->req.length = 0;
1477 			rdma_req->req.iovcnt = 0;
1478 			rdma_req->req.data = NULL;
1479 			spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_FREE);
1480 			break;
1481 		case RDMA_REQUEST_NUM_STATES:
1482 		default:
1483 			assert(0);
1484 			break;
1485 		}
1486 
1487 		if (rdma_req->state != prev_state) {
1488 			progress = true;
1489 		}
1490 	} while (rdma_req->state != prev_state);
1491 
1492 	return progress;
1493 }
1494 
1495 /* Public API callbacks begin here */
1496 
1497 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
1498 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
1499 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 64
1500 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
1501 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
1502 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE 4096
1503 #define SPDK_NVMF_RDMA_DEFAULT_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
1504 
1505 static void
1506 spdk_nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
1507 {
1508 	opts->max_queue_depth =      SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
1509 	opts->max_qpairs_per_ctrlr = SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
1510 	opts->in_capsule_data_size = SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
1511 	opts->max_io_size =          SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
1512 	opts->io_unit_size =         spdk_max(SPDK_NVMF_RDMA_DEFAULT_IO_BUFFER_SIZE,
1513 					      SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
1514 	opts->max_aq_depth =         SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
1515 }
1516 
1517 static int spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport);
1518 
1519 static struct spdk_nvmf_transport *
1520 spdk_nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
1521 {
1522 	int rc;
1523 	struct spdk_nvmf_rdma_transport *rtransport;
1524 	struct spdk_nvmf_rdma_device	*device, *tmp;
1525 	struct ibv_context		**contexts;
1526 	uint32_t			i;
1527 	int				flag;
1528 	uint32_t			sge_count;
1529 
1530 	const struct spdk_mem_map_ops nvmf_rdma_map_ops = {
1531 		.notify_cb = spdk_nvmf_rdma_mem_notify,
1532 		.are_contiguous = NULL
1533 	};
1534 
1535 	rtransport = calloc(1, sizeof(*rtransport));
1536 	if (!rtransport) {
1537 		return NULL;
1538 	}
1539 
1540 	if (pthread_mutex_init(&rtransport->lock, NULL)) {
1541 		SPDK_ERRLOG("pthread_mutex_init() failed\n");
1542 		free(rtransport);
1543 		return NULL;
1544 	}
1545 
1546 	spdk_io_device_register(rtransport, spdk_nvmf_rdma_mgmt_channel_create,
1547 				spdk_nvmf_rdma_mgmt_channel_destroy,
1548 				sizeof(struct spdk_nvmf_rdma_mgmt_channel),
1549 				"rdma_transport");
1550 
1551 	TAILQ_INIT(&rtransport->devices);
1552 	TAILQ_INIT(&rtransport->ports);
1553 
1554 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
1555 
1556 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** RDMA Transport Init ***\n"
1557 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
1558 		     "  max_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
1559 		     "  in_capsule_data_size=%d, max_aq_depth=%d\n",
1560 		     opts->max_queue_depth,
1561 		     opts->max_io_size,
1562 		     opts->max_qpairs_per_ctrlr,
1563 		     opts->io_unit_size,
1564 		     opts->in_capsule_data_size,
1565 		     opts->max_aq_depth);
1566 
1567 	/* I/O unit size cannot be larger than max I/O size */
1568 	if (opts->io_unit_size > opts->max_io_size) {
1569 		opts->io_unit_size = opts->max_io_size;
1570 	}
1571 
1572 	sge_count = opts->max_io_size / opts->io_unit_size;
1573 	if (sge_count > SPDK_NVMF_MAX_SGL_ENTRIES) {
1574 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
1575 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1576 		return NULL;
1577 	}
1578 
1579 	rtransport->event_channel = rdma_create_event_channel();
1580 	if (rtransport->event_channel == NULL) {
1581 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
1582 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1583 		return NULL;
1584 	}
1585 
1586 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
1587 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
1588 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
1589 			    rtransport->event_channel->fd, spdk_strerror(errno));
1590 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1591 		return NULL;
1592 	}
1593 
1594 	/* The maximum number of buffers we will need for a given request is equal to just less than double the number of SGL elements */
1595 	rtransport->data_buf_pool = spdk_mempool_create("spdk_nvmf_rdma",
1596 				    opts->max_queue_depth * (SPDK_NVMF_MAX_SGL_ENTRIES * 2) * 4,
1597 				    opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT,
1598 				    SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
1599 				    SPDK_ENV_SOCKET_ID_ANY);
1600 	if (!rtransport->data_buf_pool) {
1601 		SPDK_ERRLOG("Unable to allocate buffer pool for poll group\n");
1602 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1603 		return NULL;
1604 	}
1605 
1606 	contexts = rdma_get_devices(NULL);
1607 	if (contexts == NULL) {
1608 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
1609 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1610 		return NULL;
1611 	}
1612 
1613 	i = 0;
1614 	rc = 0;
1615 	while (contexts[i] != NULL) {
1616 		device = calloc(1, sizeof(*device));
1617 		if (!device) {
1618 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
1619 			rc = -ENOMEM;
1620 			break;
1621 		}
1622 		device->context = contexts[i];
1623 		rc = ibv_query_device(device->context, &device->attr);
1624 		if (rc < 0) {
1625 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
1626 			free(device);
1627 			break;
1628 
1629 		}
1630 
1631 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1632 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
1633 			SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
1634 			SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
1635 		}
1636 
1637 		/**
1638 		 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
1639 		 * The Soft-RoCE RXE driver does not currently support send with invalidate,
1640 		 * but incorrectly reports that it does. There are changes making their way
1641 		 * through the kernel now that will enable this feature. When they are merged,
1642 		 * we can conditionally enable this feature.
1643 		 *
1644 		 * TODO: enable this for versions of the kernel rxe driver that support it.
1645 		 */
1646 		if (device->attr.vendor_id == 0) {
1647 			device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
1648 		}
1649 #endif
1650 
1651 		/* set up device context async ev fd as NON_BLOCKING */
1652 		flag = fcntl(device->context->async_fd, F_GETFL);
1653 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
1654 		if (rc < 0) {
1655 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
1656 			free(device);
1657 			break;
1658 		}
1659 
1660 		device->pd = ibv_alloc_pd(device->context);
1661 		if (!device->pd) {
1662 			SPDK_ERRLOG("Unable to allocate protection domain.\n");
1663 			free(device);
1664 			rc = -1;
1665 			break;
1666 		}
1667 
1668 		device->map = spdk_mem_map_alloc(0, &nvmf_rdma_map_ops, device);
1669 		if (!device->map) {
1670 			SPDK_ERRLOG("Unable to allocate memory map for new poll group\n");
1671 			ibv_dealloc_pd(device->pd);
1672 			free(device);
1673 			rc = -1;
1674 			break;
1675 		}
1676 
1677 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
1678 		i++;
1679 	}
1680 	rdma_free_devices(contexts);
1681 
1682 	if (rc < 0) {
1683 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1684 		return NULL;
1685 	}
1686 
1687 	/* Set up poll descriptor array to monitor events from RDMA and IB
1688 	 * in a single poll syscall
1689 	 */
1690 	rtransport->npoll_fds = i + 1;
1691 	i = 0;
1692 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
1693 	if (rtransport->poll_fds == NULL) {
1694 		SPDK_ERRLOG("poll_fds allocation failed\n");
1695 		spdk_nvmf_rdma_destroy(&rtransport->transport);
1696 		return NULL;
1697 	}
1698 
1699 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
1700 	rtransport->poll_fds[i++].events = POLLIN;
1701 
1702 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
1703 		rtransport->poll_fds[i].fd = device->context->async_fd;
1704 		rtransport->poll_fds[i++].events = POLLIN;
1705 	}
1706 
1707 	return &rtransport->transport;
1708 }
1709 
1710 static int
1711 spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport)
1712 {
1713 	struct spdk_nvmf_rdma_transport	*rtransport;
1714 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
1715 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
1716 
1717 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1718 
1719 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
1720 		TAILQ_REMOVE(&rtransport->ports, port, link);
1721 		rdma_destroy_id(port->id);
1722 		free(port);
1723 	}
1724 
1725 	if (rtransport->poll_fds != NULL) {
1726 		free(rtransport->poll_fds);
1727 	}
1728 
1729 	if (rtransport->event_channel != NULL) {
1730 		rdma_destroy_event_channel(rtransport->event_channel);
1731 	}
1732 
1733 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
1734 		TAILQ_REMOVE(&rtransport->devices, device, link);
1735 		if (device->map) {
1736 			spdk_mem_map_free(&device->map);
1737 		}
1738 		if (device->pd) {
1739 			ibv_dealloc_pd(device->pd);
1740 		}
1741 		free(device);
1742 	}
1743 
1744 	if (rtransport->data_buf_pool != NULL) {
1745 		if (spdk_mempool_count(rtransport->data_buf_pool) !=
1746 		    (transport->opts.max_queue_depth * (SPDK_NVMF_MAX_SGL_ENTRIES * 2) * 4)) {
1747 			SPDK_ERRLOG("transport buffer pool count is %zu but should be %u\n",
1748 				    spdk_mempool_count(rtransport->data_buf_pool),
1749 				    transport->opts.max_queue_depth * (SPDK_NVMF_MAX_SGL_ENTRIES * 2) * 4);
1750 		}
1751 	}
1752 
1753 	spdk_mempool_free(rtransport->data_buf_pool);
1754 	spdk_io_device_unregister(rtransport, NULL);
1755 	pthread_mutex_destroy(&rtransport->lock);
1756 	free(rtransport);
1757 
1758 	return 0;
1759 }
1760 
1761 static int
1762 spdk_nvmf_rdma_listen(struct spdk_nvmf_transport *transport,
1763 		      const struct spdk_nvme_transport_id *trid)
1764 {
1765 	struct spdk_nvmf_rdma_transport	*rtransport;
1766 	struct spdk_nvmf_rdma_device	*device;
1767 	struct spdk_nvmf_rdma_port	*port_tmp, *port;
1768 	struct addrinfo			*res;
1769 	struct addrinfo			hints;
1770 	int				family;
1771 	int				rc;
1772 
1773 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1774 
1775 	port = calloc(1, sizeof(*port));
1776 	if (!port) {
1777 		return -ENOMEM;
1778 	}
1779 
1780 	/* Selectively copy the trid. Things like NQN don't matter here - that
1781 	 * mapping is enforced elsewhere.
1782 	 */
1783 	port->trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
1784 	port->trid.adrfam = trid->adrfam;
1785 	snprintf(port->trid.traddr, sizeof(port->trid.traddr), "%s", trid->traddr);
1786 	snprintf(port->trid.trsvcid, sizeof(port->trid.trsvcid), "%s", trid->trsvcid);
1787 
1788 	pthread_mutex_lock(&rtransport->lock);
1789 	assert(rtransport->event_channel != NULL);
1790 	TAILQ_FOREACH(port_tmp, &rtransport->ports, link) {
1791 		if (spdk_nvme_transport_id_compare(&port_tmp->trid, &port->trid) == 0) {
1792 			port_tmp->ref++;
1793 			free(port);
1794 			/* Already listening at this address */
1795 			pthread_mutex_unlock(&rtransport->lock);
1796 			return 0;
1797 		}
1798 	}
1799 
1800 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
1801 	if (rc < 0) {
1802 		SPDK_ERRLOG("rdma_create_id() failed\n");
1803 		free(port);
1804 		pthread_mutex_unlock(&rtransport->lock);
1805 		return rc;
1806 	}
1807 
1808 	switch (port->trid.adrfam) {
1809 	case SPDK_NVMF_ADRFAM_IPV4:
1810 		family = AF_INET;
1811 		break;
1812 	case SPDK_NVMF_ADRFAM_IPV6:
1813 		family = AF_INET6;
1814 		break;
1815 	default:
1816 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", port->trid.adrfam);
1817 		free(port);
1818 		pthread_mutex_unlock(&rtransport->lock);
1819 		return -EINVAL;
1820 	}
1821 
1822 	memset(&hints, 0, sizeof(hints));
1823 	hints.ai_family = family;
1824 	hints.ai_flags = AI_NUMERICSERV;
1825 	hints.ai_socktype = SOCK_STREAM;
1826 	hints.ai_protocol = 0;
1827 
1828 	rc = getaddrinfo(port->trid.traddr, port->trid.trsvcid, &hints, &res);
1829 	if (rc) {
1830 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
1831 		free(port);
1832 		pthread_mutex_unlock(&rtransport->lock);
1833 		return -EINVAL;
1834 	}
1835 
1836 	rc = rdma_bind_addr(port->id, res->ai_addr);
1837 	freeaddrinfo(res);
1838 
1839 	if (rc < 0) {
1840 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
1841 		rdma_destroy_id(port->id);
1842 		free(port);
1843 		pthread_mutex_unlock(&rtransport->lock);
1844 		return rc;
1845 	}
1846 
1847 	if (!port->id->verbs) {
1848 		SPDK_ERRLOG("ibv_context is null\n");
1849 		rdma_destroy_id(port->id);
1850 		free(port);
1851 		pthread_mutex_unlock(&rtransport->lock);
1852 		return -1;
1853 	}
1854 
1855 	rc = rdma_listen(port->id, 10); /* 10 = backlog */
1856 	if (rc < 0) {
1857 		SPDK_ERRLOG("rdma_listen() failed\n");
1858 		rdma_destroy_id(port->id);
1859 		free(port);
1860 		pthread_mutex_unlock(&rtransport->lock);
1861 		return rc;
1862 	}
1863 
1864 	TAILQ_FOREACH(device, &rtransport->devices, link) {
1865 		if (device->context == port->id->verbs) {
1866 			port->device = device;
1867 			break;
1868 		}
1869 	}
1870 	if (!port->device) {
1871 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
1872 			    port->id->verbs);
1873 		rdma_destroy_id(port->id);
1874 		free(port);
1875 		pthread_mutex_unlock(&rtransport->lock);
1876 		return -EINVAL;
1877 	}
1878 
1879 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** NVMf Target Listening on %s port %d ***\n",
1880 		     port->trid.traddr, ntohs(rdma_get_src_port(port->id)));
1881 
1882 	port->ref = 1;
1883 
1884 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
1885 	pthread_mutex_unlock(&rtransport->lock);
1886 
1887 	return 0;
1888 }
1889 
1890 static int
1891 spdk_nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
1892 			   const struct spdk_nvme_transport_id *_trid)
1893 {
1894 	struct spdk_nvmf_rdma_transport *rtransport;
1895 	struct spdk_nvmf_rdma_port *port, *tmp;
1896 	struct spdk_nvme_transport_id trid = {};
1897 
1898 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1899 
1900 	/* Selectively copy the trid. Things like NQN don't matter here - that
1901 	 * mapping is enforced elsewhere.
1902 	 */
1903 	trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
1904 	trid.adrfam = _trid->adrfam;
1905 	snprintf(trid.traddr, sizeof(port->trid.traddr), "%s", _trid->traddr);
1906 	snprintf(trid.trsvcid, sizeof(port->trid.trsvcid), "%s", _trid->trsvcid);
1907 
1908 	pthread_mutex_lock(&rtransport->lock);
1909 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
1910 		if (spdk_nvme_transport_id_compare(&port->trid, &trid) == 0) {
1911 			assert(port->ref > 0);
1912 			port->ref--;
1913 			if (port->ref == 0) {
1914 				TAILQ_REMOVE(&rtransport->ports, port, link);
1915 				rdma_destroy_id(port->id);
1916 				free(port);
1917 			}
1918 			break;
1919 		}
1920 	}
1921 
1922 	pthread_mutex_unlock(&rtransport->lock);
1923 	return 0;
1924 }
1925 
1926 static bool
1927 spdk_nvmf_rdma_qpair_is_idle(struct spdk_nvmf_qpair *qpair)
1928 {
1929 	int cur_queue_depth, cur_rdma_rw_depth;
1930 	struct spdk_nvmf_rdma_qpair *rqpair;
1931 
1932 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1933 	cur_queue_depth = spdk_nvmf_rdma_cur_queue_depth(rqpair);
1934 	cur_rdma_rw_depth = spdk_nvmf_rdma_cur_rw_depth(rqpair);
1935 
1936 	if (cur_queue_depth == 0 && cur_rdma_rw_depth == 0) {
1937 		return true;
1938 	}
1939 	return false;
1940 }
1941 
1942 static void
1943 spdk_nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
1944 				     struct spdk_nvmf_rdma_qpair *rqpair)
1945 {
1946 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
1947 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
1948 
1949 	/* We process I/O in the data transfer pending queue at the highest priority. */
1950 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->state_queue[RDMA_REQUEST_STATE_DATA_TRANSFER_PENDING],
1951 			   state_link, req_tmp) {
1952 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false) {
1953 			break;
1954 		}
1955 	}
1956 
1957 	/* The second highest priority is I/O waiting on memory buffers. */
1958 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->ch->pending_data_buf_queue, link,
1959 			   req_tmp) {
1960 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false) {
1961 			break;
1962 		}
1963 	}
1964 
1965 	/* The lowest priority is processing newly received commands */
1966 	TAILQ_FOREACH_SAFE(rdma_recv, &rqpair->incoming_queue, link, recv_tmp) {
1967 		if (TAILQ_EMPTY(&rqpair->state_queue[RDMA_REQUEST_STATE_FREE])) {
1968 			break;
1969 		}
1970 
1971 		rdma_req = TAILQ_FIRST(&rqpair->state_queue[RDMA_REQUEST_STATE_FREE]);
1972 		rdma_req->recv = rdma_recv;
1973 		spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_NEW);
1974 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false) {
1975 			break;
1976 		}
1977 	}
1978 }
1979 
1980 static void
1981 _nvmf_rdma_qpair_disconnect(void *ctx)
1982 {
1983 	struct spdk_nvmf_qpair *qpair = ctx;
1984 	struct spdk_nvmf_rdma_qpair *rqpair;
1985 
1986 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1987 
1988 	spdk_nvmf_rdma_qpair_dec_refcnt(rqpair);
1989 
1990 	spdk_nvmf_qpair_disconnect(qpair, NULL, NULL);
1991 }
1992 
1993 static void
1994 _nvmf_rdma_disconnect_retry(void *ctx)
1995 {
1996 	struct spdk_nvmf_qpair *qpair = ctx;
1997 	struct spdk_nvmf_poll_group *group;
1998 
1999 	/* Read the group out of the qpair. This is normally set and accessed only from
2000 	 * the thread that created the group. Here, we're not on that thread necessarily.
2001 	 * The data member qpair->group begins it's life as NULL and then is assigned to
2002 	 * a pointer and never changes. So fortunately reading this and checking for
2003 	 * non-NULL is thread safe in the x86_64 memory model. */
2004 	group = qpair->group;
2005 
2006 	if (group == NULL) {
2007 		/* The qpair hasn't been assigned to a group yet, so we can't
2008 		 * process a disconnect. Send a message to ourself and try again. */
2009 		spdk_thread_send_msg(spdk_get_thread(), _nvmf_rdma_disconnect_retry, qpair);
2010 		return;
2011 	}
2012 
2013 	spdk_thread_send_msg(group->thread, _nvmf_rdma_qpair_disconnect, qpair);
2014 }
2015 
2016 static int
2017 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
2018 {
2019 	struct spdk_nvmf_qpair		*qpair;
2020 	struct spdk_nvmf_rdma_qpair	*rqpair;
2021 
2022 	if (evt->id == NULL) {
2023 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
2024 		return -1;
2025 	}
2026 
2027 	qpair = evt->id->context;
2028 	if (qpair == NULL) {
2029 		SPDK_ERRLOG("disconnect request: no active connection\n");
2030 		return -1;
2031 	}
2032 
2033 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2034 
2035 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair->cm_id, 0);
2036 
2037 	spdk_nvmf_rdma_update_ibv_state(rqpair);
2038 	spdk_nvmf_rdma_qpair_inc_refcnt(rqpair);
2039 
2040 	_nvmf_rdma_disconnect_retry(qpair);
2041 
2042 	return 0;
2043 }
2044 
2045 #ifdef DEBUG
2046 static const char *CM_EVENT_STR[] = {
2047 	"RDMA_CM_EVENT_ADDR_RESOLVED",
2048 	"RDMA_CM_EVENT_ADDR_ERROR",
2049 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
2050 	"RDMA_CM_EVENT_ROUTE_ERROR",
2051 	"RDMA_CM_EVENT_CONNECT_REQUEST",
2052 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
2053 	"RDMA_CM_EVENT_CONNECT_ERROR",
2054 	"RDMA_CM_EVENT_UNREACHABLE",
2055 	"RDMA_CM_EVENT_REJECTED",
2056 	"RDMA_CM_EVENT_ESTABLISHED",
2057 	"RDMA_CM_EVENT_DISCONNECTED",
2058 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
2059 	"RDMA_CM_EVENT_MULTICAST_JOIN",
2060 	"RDMA_CM_EVENT_MULTICAST_ERROR",
2061 	"RDMA_CM_EVENT_ADDR_CHANGE",
2062 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
2063 };
2064 #endif /* DEBUG */
2065 
2066 static void
2067 spdk_nvmf_process_cm_event(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
2068 {
2069 	struct spdk_nvmf_rdma_transport *rtransport;
2070 	struct rdma_cm_event		*event;
2071 	int				rc;
2072 
2073 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2074 
2075 	if (rtransport->event_channel == NULL) {
2076 		return;
2077 	}
2078 
2079 	while (1) {
2080 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
2081 		if (rc == 0) {
2082 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
2083 
2084 			spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
2085 
2086 			switch (event->event) {
2087 			case RDMA_CM_EVENT_ADDR_RESOLVED:
2088 			case RDMA_CM_EVENT_ADDR_ERROR:
2089 			case RDMA_CM_EVENT_ROUTE_RESOLVED:
2090 			case RDMA_CM_EVENT_ROUTE_ERROR:
2091 				/* No action required. The target never attempts to resolve routes. */
2092 				break;
2093 			case RDMA_CM_EVENT_CONNECT_REQUEST:
2094 				rc = nvmf_rdma_connect(transport, event, cb_fn);
2095 				if (rc < 0) {
2096 					SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
2097 					break;
2098 				}
2099 				break;
2100 			case RDMA_CM_EVENT_CONNECT_RESPONSE:
2101 				/* The target never initiates a new connection. So this will not occur. */
2102 				break;
2103 			case RDMA_CM_EVENT_CONNECT_ERROR:
2104 				/* Can this happen? The docs say it can, but not sure what causes it. */
2105 				break;
2106 			case RDMA_CM_EVENT_UNREACHABLE:
2107 			case RDMA_CM_EVENT_REJECTED:
2108 				/* These only occur on the client side. */
2109 				break;
2110 			case RDMA_CM_EVENT_ESTABLISHED:
2111 				/* TODO: Should we be waiting for this event anywhere? */
2112 				break;
2113 			case RDMA_CM_EVENT_DISCONNECTED:
2114 			case RDMA_CM_EVENT_DEVICE_REMOVAL:
2115 				rc = nvmf_rdma_disconnect(event);
2116 				if (rc < 0) {
2117 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
2118 					break;
2119 				}
2120 				break;
2121 			case RDMA_CM_EVENT_MULTICAST_JOIN:
2122 			case RDMA_CM_EVENT_MULTICAST_ERROR:
2123 				/* Multicast is not used */
2124 				break;
2125 			case RDMA_CM_EVENT_ADDR_CHANGE:
2126 				/* Not utilizing this event */
2127 				break;
2128 			case RDMA_CM_EVENT_TIMEWAIT_EXIT:
2129 				/* For now, do nothing. The target never re-uses queue pairs. */
2130 				break;
2131 			default:
2132 				SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
2133 				break;
2134 			}
2135 
2136 			rdma_ack_cm_event(event);
2137 		} else {
2138 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
2139 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
2140 			}
2141 			break;
2142 		}
2143 	}
2144 }
2145 
2146 static void
2147 spdk_nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
2148 {
2149 	int				rc;
2150 	struct spdk_nvmf_rdma_qpair	*rqpair;
2151 	struct ibv_async_event		event;
2152 	enum ibv_qp_state		state;
2153 
2154 	rc = ibv_get_async_event(device->context, &event);
2155 
2156 	if (rc) {
2157 		SPDK_ERRLOG("Failed to get async_event (%d): %s\n",
2158 			    errno, spdk_strerror(errno));
2159 		return;
2160 	}
2161 
2162 	SPDK_NOTICELOG("Async event: %s\n",
2163 		       ibv_event_type_str(event.event_type));
2164 
2165 	switch (event.event_type) {
2166 	case IBV_EVENT_QP_FATAL:
2167 		rqpair = event.element.qp->qp_context;
2168 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
2169 				  (uintptr_t)rqpair->cm_id, event.event_type);
2170 		spdk_nvmf_rdma_update_ibv_state(rqpair);
2171 		spdk_nvmf_rdma_qpair_inc_refcnt(rqpair);
2172 		spdk_thread_send_msg(rqpair->qpair.group->thread, _nvmf_rdma_qpair_disconnect, &rqpair->qpair);
2173 		break;
2174 	case IBV_EVENT_QP_LAST_WQE_REACHED:
2175 		/* This event only occurs for shared receive queues, which are not currently supported. */
2176 		break;
2177 	case IBV_EVENT_SQ_DRAINED:
2178 		/* This event occurs frequently in both error and non-error states.
2179 		 * Check if the qpair is in an error state before sending a message.
2180 		 * Note that we're not on the correct thread to access the qpair, but
2181 		 * the operations that the below calls make all happen to be thread
2182 		 * safe. */
2183 		rqpair = event.element.qp->qp_context;
2184 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
2185 				  (uintptr_t)rqpair->cm_id, event.event_type);
2186 		state = spdk_nvmf_rdma_update_ibv_state(rqpair);
2187 		if (state == IBV_QPS_ERR) {
2188 			spdk_nvmf_rdma_qpair_inc_refcnt(rqpair);
2189 			spdk_thread_send_msg(rqpair->qpair.group->thread, _nvmf_rdma_qpair_disconnect, &rqpair->qpair);
2190 		}
2191 		break;
2192 	case IBV_EVENT_QP_REQ_ERR:
2193 	case IBV_EVENT_QP_ACCESS_ERR:
2194 	case IBV_EVENT_COMM_EST:
2195 	case IBV_EVENT_PATH_MIG:
2196 	case IBV_EVENT_PATH_MIG_ERR:
2197 		rqpair = event.element.qp->qp_context;
2198 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
2199 				  (uintptr_t)rqpair->cm_id, event.event_type);
2200 		spdk_nvmf_rdma_update_ibv_state(rqpair);
2201 		break;
2202 	case IBV_EVENT_CQ_ERR:
2203 	case IBV_EVENT_DEVICE_FATAL:
2204 	case IBV_EVENT_PORT_ACTIVE:
2205 	case IBV_EVENT_PORT_ERR:
2206 	case IBV_EVENT_LID_CHANGE:
2207 	case IBV_EVENT_PKEY_CHANGE:
2208 	case IBV_EVENT_SM_CHANGE:
2209 	case IBV_EVENT_SRQ_ERR:
2210 	case IBV_EVENT_SRQ_LIMIT_REACHED:
2211 	case IBV_EVENT_CLIENT_REREGISTER:
2212 	case IBV_EVENT_GID_CHANGE:
2213 	default:
2214 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
2215 		break;
2216 	}
2217 	ibv_ack_async_event(&event);
2218 }
2219 
2220 static void
2221 spdk_nvmf_rdma_accept(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
2222 {
2223 	int	nfds, i = 0;
2224 	struct spdk_nvmf_rdma_transport *rtransport;
2225 	struct spdk_nvmf_rdma_device *device, *tmp;
2226 
2227 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2228 	nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
2229 
2230 	if (nfds <= 0) {
2231 		return;
2232 	}
2233 
2234 	/* The first poll descriptor is RDMA CM event */
2235 	if (rtransport->poll_fds[i++].revents & POLLIN) {
2236 		spdk_nvmf_process_cm_event(transport, cb_fn);
2237 		nfds--;
2238 	}
2239 
2240 	if (nfds == 0) {
2241 		return;
2242 	}
2243 
2244 	/* Second and subsequent poll descriptors are IB async events */
2245 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2246 		if (rtransport->poll_fds[i++].revents & POLLIN) {
2247 			spdk_nvmf_process_ib_event(device);
2248 			nfds--;
2249 		}
2250 	}
2251 	/* check all flagged fd's have been served */
2252 	assert(nfds == 0);
2253 }
2254 
2255 static void
2256 spdk_nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
2257 			struct spdk_nvme_transport_id *trid,
2258 			struct spdk_nvmf_discovery_log_page_entry *entry)
2259 {
2260 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
2261 	entry->adrfam = trid->adrfam;
2262 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_SPECIFIED;
2263 
2264 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
2265 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
2266 
2267 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
2268 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
2269 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
2270 }
2271 
2272 static struct spdk_nvmf_transport_poll_group *
2273 spdk_nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
2274 {
2275 	struct spdk_nvmf_rdma_transport		*rtransport;
2276 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2277 	struct spdk_nvmf_rdma_poller		*poller;
2278 	struct spdk_nvmf_rdma_device		*device;
2279 
2280 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2281 
2282 	rgroup = calloc(1, sizeof(*rgroup));
2283 	if (!rgroup) {
2284 		return NULL;
2285 	}
2286 
2287 	TAILQ_INIT(&rgroup->pollers);
2288 
2289 	pthread_mutex_lock(&rtransport->lock);
2290 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2291 		poller = calloc(1, sizeof(*poller));
2292 		if (!poller) {
2293 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
2294 			free(rgroup);
2295 			pthread_mutex_unlock(&rtransport->lock);
2296 			return NULL;
2297 		}
2298 
2299 		poller->device = device;
2300 		poller->group = rgroup;
2301 
2302 		TAILQ_INIT(&poller->qpairs);
2303 
2304 		poller->cq = ibv_create_cq(device->context, NVMF_RDMA_CQ_SIZE, poller, NULL, 0);
2305 		if (!poller->cq) {
2306 			SPDK_ERRLOG("Unable to create completion queue\n");
2307 			free(poller);
2308 			free(rgroup);
2309 			pthread_mutex_unlock(&rtransport->lock);
2310 			return NULL;
2311 		}
2312 
2313 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
2314 	}
2315 
2316 	pthread_mutex_unlock(&rtransport->lock);
2317 	return &rgroup->group;
2318 }
2319 
2320 static void
2321 spdk_nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
2322 {
2323 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2324 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
2325 	struct spdk_nvmf_rdma_qpair		*qpair, *tmp_qpair;
2326 
2327 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
2328 
2329 	if (!rgroup) {
2330 		return;
2331 	}
2332 
2333 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
2334 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
2335 
2336 		if (poller->cq) {
2337 			ibv_destroy_cq(poller->cq);
2338 		}
2339 		TAILQ_FOREACH_SAFE(qpair, &poller->qpairs, link, tmp_qpair) {
2340 			spdk_nvmf_rdma_qpair_destroy(qpair);
2341 		}
2342 
2343 		free(poller);
2344 	}
2345 
2346 	free(rgroup);
2347 }
2348 
2349 static int
2350 spdk_nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
2351 			      struct spdk_nvmf_qpair *qpair)
2352 {
2353 	struct spdk_nvmf_rdma_transport		*rtransport;
2354 	struct spdk_nvmf_rdma_poll_group	*rgroup;
2355 	struct spdk_nvmf_rdma_qpair		*rqpair;
2356 	struct spdk_nvmf_rdma_device		*device;
2357 	struct spdk_nvmf_rdma_poller		*poller;
2358 	int					rc;
2359 
2360 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
2361 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
2362 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2363 
2364 	device = rqpair->port->device;
2365 
2366 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
2367 		if (poller->device == device) {
2368 			break;
2369 		}
2370 	}
2371 
2372 	if (!poller) {
2373 		SPDK_ERRLOG("No poller found for device.\n");
2374 		return -1;
2375 	}
2376 
2377 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
2378 	rqpair->poller = poller;
2379 
2380 	rc = spdk_nvmf_rdma_qpair_initialize(qpair);
2381 	if (rc < 0) {
2382 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
2383 		return -1;
2384 	}
2385 
2386 	rqpair->mgmt_channel = spdk_get_io_channel(rtransport);
2387 	if (!rqpair->mgmt_channel) {
2388 		spdk_nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
2389 		spdk_nvmf_rdma_qpair_destroy(rqpair);
2390 		return -1;
2391 	}
2392 
2393 	rqpair->ch = spdk_io_channel_get_ctx(rqpair->mgmt_channel);
2394 	assert(rqpair->ch != NULL);
2395 
2396 	rc = spdk_nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
2397 	if (rc) {
2398 		/* Try to reject, but we probably can't */
2399 		spdk_nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
2400 		spdk_nvmf_rdma_qpair_destroy(rqpair);
2401 		return -1;
2402 	}
2403 
2404 	spdk_nvmf_rdma_update_ibv_state(rqpair);
2405 
2406 	return 0;
2407 }
2408 
2409 static int
2410 spdk_nvmf_rdma_request_free(struct spdk_nvmf_request *req)
2411 {
2412 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
2413 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
2414 			struct spdk_nvmf_rdma_transport, transport);
2415 
2416 	if (rdma_req->data_from_pool) {
2417 		/* Put the buffer/s back in the pool */
2418 		for (uint32_t i = 0; i < rdma_req->req.iovcnt; i++) {
2419 			spdk_mempool_put(rtransport->data_buf_pool, rdma_req->data.buffers[i]);
2420 			rdma_req->req.iov[i].iov_base = NULL;
2421 			rdma_req->data.buffers[i] = NULL;
2422 		}
2423 		rdma_req->data_from_pool = false;
2424 	}
2425 	rdma_req->req.length = 0;
2426 	rdma_req->req.iovcnt = 0;
2427 	rdma_req->req.data = NULL;
2428 	spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_FREE);
2429 	return 0;
2430 }
2431 
2432 static int
2433 spdk_nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
2434 {
2435 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
2436 			struct spdk_nvmf_rdma_transport, transport);
2437 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
2438 			struct spdk_nvmf_rdma_request, req);
2439 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
2440 			struct spdk_nvmf_rdma_qpair, qpair);
2441 
2442 	if (rqpair->ibv_attr.qp_state != IBV_QPS_ERR) {
2443 		/* The connection is alive, so process the request as normal */
2444 		spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_EXECUTED);
2445 	} else {
2446 		/* The connection is dead. Move the request directly to the completed state. */
2447 		spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_COMPLETED);
2448 	}
2449 
2450 	spdk_nvmf_rdma_request_process(rtransport, rdma_req);
2451 
2452 	return 0;
2453 }
2454 
2455 static void
2456 spdk_nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair)
2457 {
2458 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2459 	struct ibv_recv_wr recv_wr = {};
2460 	struct ibv_recv_wr *bad_recv_wr;
2461 	struct ibv_send_wr send_wr = {};
2462 	struct ibv_send_wr *bad_send_wr;
2463 	int rc;
2464 
2465 	if (rqpair->disconnect_flags & RDMA_QP_DISCONNECTING) {
2466 		return;
2467 	}
2468 
2469 	rqpair->disconnect_flags |= RDMA_QP_DISCONNECTING;
2470 
2471 	if (rqpair->ibv_attr.qp_state != IBV_QPS_ERR) {
2472 		spdk_nvmf_rdma_set_ibv_state(rqpair, IBV_QPS_ERR);
2473 	}
2474 
2475 	rqpair->drain_recv_wr.type = RDMA_WR_TYPE_DRAIN_RECV;
2476 	recv_wr.wr_id = (uintptr_t)&rqpair->drain_recv_wr;
2477 	rc = ibv_post_recv(rqpair->cm_id->qp, &recv_wr, &bad_recv_wr);
2478 	if (rc) {
2479 		SPDK_ERRLOG("Failed to post dummy receive WR, errno %d\n", errno);
2480 		assert(false);
2481 		return;
2482 	}
2483 
2484 	rqpair->drain_send_wr.type = RDMA_WR_TYPE_DRAIN_SEND;
2485 	send_wr.wr_id = (uintptr_t)&rqpair->drain_send_wr;
2486 	send_wr.opcode = IBV_WR_SEND;
2487 	rc = ibv_post_send(rqpair->cm_id->qp, &send_wr, &bad_send_wr);
2488 	if (rc) {
2489 		SPDK_ERRLOG("Failed to post dummy send WR, errno %d\n", errno);
2490 		assert(false);
2491 		return;
2492 	}
2493 }
2494 
2495 #ifdef DEBUG
2496 static int
2497 spdk_nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
2498 {
2499 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
2500 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
2501 }
2502 #endif
2503 
2504 static int
2505 spdk_nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
2506 			   struct spdk_nvmf_rdma_poller *rpoller)
2507 {
2508 	struct ibv_wc wc[32];
2509 	struct spdk_nvmf_rdma_wr	*rdma_wr;
2510 	struct spdk_nvmf_rdma_request	*rdma_req;
2511 	struct spdk_nvmf_rdma_recv	*rdma_recv;
2512 	struct spdk_nvmf_rdma_qpair	*rqpair;
2513 	int reaped, i;
2514 	int count = 0;
2515 	bool error = false;
2516 
2517 	/* Poll for completing operations. */
2518 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
2519 	if (reaped < 0) {
2520 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
2521 			    errno, spdk_strerror(errno));
2522 		return -1;
2523 	}
2524 
2525 	for (i = 0; i < reaped; i++) {
2526 
2527 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
2528 
2529 		/* Handle error conditions */
2530 		if (wc[i].status) {
2531 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "CQ error on CQ %p, Request 0x%lu (%d): %s\n",
2532 				      rpoller->cq, wc[i].wr_id, wc[i].status, ibv_wc_status_str(wc[i].status));
2533 
2534 			error = true;
2535 
2536 			switch (rdma_wr->type) {
2537 			case RDMA_WR_TYPE_SEND:
2538 				rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
2539 				rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
2540 
2541 				/* We're going to attempt an error recovery, so force the request into
2542 				 * the completed state. */
2543 				spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_COMPLETED);
2544 				spdk_nvmf_rdma_request_process(rtransport, rdma_req);
2545 				break;
2546 			case RDMA_WR_TYPE_RECV:
2547 				rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
2548 				rqpair = rdma_recv->qpair;
2549 
2550 				/* Dump this into the incoming queue. This gets cleaned up when
2551 				 * the queue pair disconnects or recovers. */
2552 				TAILQ_INSERT_TAIL(&rqpair->incoming_queue, rdma_recv, link);
2553 				break;
2554 			case RDMA_WR_TYPE_DATA:
2555 				/* If the data transfer fails still force the queue into the error state,
2556 				 * but the rdma_req objects should only be manipulated in response to
2557 				 * SEND and RECV operations. */
2558 				rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
2559 				rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
2560 				break;
2561 			case RDMA_WR_TYPE_DRAIN_RECV:
2562 				rqpair = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_qpair, drain_recv_wr);
2563 				assert(rqpair->disconnect_flags & RDMA_QP_DISCONNECTING);
2564 				SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Drained QP RECV %u (%p)\n", rqpair->qpair.qid, rqpair);
2565 				rqpair->disconnect_flags |= RDMA_QP_RECV_DRAINED;
2566 				if (rqpair->disconnect_flags & RDMA_QP_SEND_DRAINED) {
2567 					spdk_nvmf_rdma_qpair_destroy(rqpair);
2568 				}
2569 				/* Continue so that this does not trigger the disconnect path below. */
2570 				continue;
2571 			case RDMA_WR_TYPE_DRAIN_SEND:
2572 				rqpair = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_qpair, drain_send_wr);
2573 				assert(rqpair->disconnect_flags & RDMA_QP_DISCONNECTING);
2574 				SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Drained QP SEND %u (%p)\n", rqpair->qpair.qid, rqpair);
2575 				rqpair->disconnect_flags |= RDMA_QP_SEND_DRAINED;
2576 				if (rqpair->disconnect_flags & RDMA_QP_RECV_DRAINED) {
2577 					spdk_nvmf_rdma_qpair_destroy(rqpair);
2578 				}
2579 				/* Continue so that this does not trigger the disconnect path below. */
2580 				continue;
2581 			default:
2582 				SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
2583 				continue;
2584 			}
2585 
2586 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
2587 				/* Disconnect the connection. */
2588 				spdk_nvmf_qpair_disconnect(&rqpair->qpair, NULL, NULL);
2589 			}
2590 			continue;
2591 		}
2592 
2593 		switch (wc[i].opcode) {
2594 		case IBV_WC_SEND:
2595 			assert(rdma_wr->type == RDMA_WR_TYPE_SEND);
2596 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
2597 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
2598 
2599 			assert(spdk_nvmf_rdma_req_is_completing(rdma_req));
2600 
2601 			spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_COMPLETED);
2602 			spdk_nvmf_rdma_request_process(rtransport, rdma_req);
2603 
2604 			count++;
2605 
2606 			/* Try to process other queued requests */
2607 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair);
2608 			break;
2609 
2610 		case IBV_WC_RDMA_WRITE:
2611 			assert(rdma_wr->type == RDMA_WR_TYPE_DATA);
2612 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
2613 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
2614 
2615 			/* Try to process other queued requests */
2616 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair);
2617 			break;
2618 
2619 		case IBV_WC_RDMA_READ:
2620 			assert(rdma_wr->type == RDMA_WR_TYPE_DATA);
2621 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
2622 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
2623 
2624 			assert(rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
2625 			spdk_nvmf_rdma_request_set_state(rdma_req, RDMA_REQUEST_STATE_READY_TO_EXECUTE);
2626 			spdk_nvmf_rdma_request_process(rtransport, rdma_req);
2627 
2628 			/* Try to process other queued requests */
2629 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair);
2630 			break;
2631 
2632 		case IBV_WC_RECV:
2633 			assert(rdma_wr->type == RDMA_WR_TYPE_RECV);
2634 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
2635 			rqpair = rdma_recv->qpair;
2636 
2637 			TAILQ_INSERT_TAIL(&rqpair->incoming_queue, rdma_recv, link);
2638 			/* Try to process other queued requests */
2639 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair);
2640 			break;
2641 
2642 		default:
2643 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
2644 			continue;
2645 		}
2646 	}
2647 
2648 	if (error == true) {
2649 		return -1;
2650 	}
2651 
2652 	return count;
2653 }
2654 
2655 static int
2656 spdk_nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
2657 {
2658 	struct spdk_nvmf_rdma_transport *rtransport;
2659 	struct spdk_nvmf_rdma_poll_group *rgroup;
2660 	struct spdk_nvmf_rdma_poller	*rpoller;
2661 	int				count, rc;
2662 
2663 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
2664 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
2665 
2666 	count = 0;
2667 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
2668 		rc = spdk_nvmf_rdma_poller_poll(rtransport, rpoller);
2669 		if (rc < 0) {
2670 			return rc;
2671 		}
2672 		count += rc;
2673 	}
2674 
2675 	return count;
2676 }
2677 
2678 static int
2679 spdk_nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2680 			       struct spdk_nvme_transport_id *trid,
2681 			       bool peer)
2682 {
2683 	struct sockaddr *saddr;
2684 	uint16_t port;
2685 
2686 	trid->trtype = SPDK_NVME_TRANSPORT_RDMA;
2687 
2688 	if (peer) {
2689 		saddr = rdma_get_peer_addr(id);
2690 	} else {
2691 		saddr = rdma_get_local_addr(id);
2692 	}
2693 	switch (saddr->sa_family) {
2694 	case AF_INET: {
2695 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
2696 
2697 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
2698 		inet_ntop(AF_INET, &saddr_in->sin_addr,
2699 			  trid->traddr, sizeof(trid->traddr));
2700 		if (peer) {
2701 			port = ntohs(rdma_get_dst_port(id));
2702 		} else {
2703 			port = ntohs(rdma_get_src_port(id));
2704 		}
2705 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
2706 		break;
2707 	}
2708 	case AF_INET6: {
2709 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
2710 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
2711 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
2712 			  trid->traddr, sizeof(trid->traddr));
2713 		if (peer) {
2714 			port = ntohs(rdma_get_dst_port(id));
2715 		} else {
2716 			port = ntohs(rdma_get_src_port(id));
2717 		}
2718 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
2719 		break;
2720 	}
2721 	default:
2722 		return -1;
2723 
2724 	}
2725 
2726 	return 0;
2727 }
2728 
2729 static int
2730 spdk_nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
2731 				   struct spdk_nvme_transport_id *trid)
2732 {
2733 	struct spdk_nvmf_rdma_qpair	*rqpair;
2734 
2735 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2736 
2737 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
2738 }
2739 
2740 static int
2741 spdk_nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
2742 				    struct spdk_nvme_transport_id *trid)
2743 {
2744 	struct spdk_nvmf_rdma_qpair	*rqpair;
2745 
2746 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2747 
2748 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
2749 }
2750 
2751 static int
2752 spdk_nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
2753 				     struct spdk_nvme_transport_id *trid)
2754 {
2755 	struct spdk_nvmf_rdma_qpair	*rqpair;
2756 
2757 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2758 
2759 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
2760 }
2761 
2762 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
2763 	.type = SPDK_NVME_TRANSPORT_RDMA,
2764 	.opts_init = spdk_nvmf_rdma_opts_init,
2765 	.create = spdk_nvmf_rdma_create,
2766 	.destroy = spdk_nvmf_rdma_destroy,
2767 
2768 	.listen = spdk_nvmf_rdma_listen,
2769 	.stop_listen = spdk_nvmf_rdma_stop_listen,
2770 	.accept = spdk_nvmf_rdma_accept,
2771 
2772 	.listener_discover = spdk_nvmf_rdma_discover,
2773 
2774 	.poll_group_create = spdk_nvmf_rdma_poll_group_create,
2775 	.poll_group_destroy = spdk_nvmf_rdma_poll_group_destroy,
2776 	.poll_group_add = spdk_nvmf_rdma_poll_group_add,
2777 	.poll_group_poll = spdk_nvmf_rdma_poll_group_poll,
2778 
2779 	.req_free = spdk_nvmf_rdma_request_free,
2780 	.req_complete = spdk_nvmf_rdma_request_complete,
2781 
2782 	.qpair_fini = spdk_nvmf_rdma_close_qpair,
2783 	.qpair_is_idle = spdk_nvmf_rdma_qpair_is_idle,
2784 	.qpair_get_peer_trid = spdk_nvmf_rdma_qpair_get_peer_trid,
2785 	.qpair_get_local_trid = spdk_nvmf_rdma_qpair_get_local_trid,
2786 	.qpair_get_listen_trid = spdk_nvmf_rdma_qpair_get_listen_trid,
2787 
2788 };
2789 
2790 SPDK_LOG_REGISTER_COMPONENT("rdma", SPDK_LOG_RDMA)
2791