xref: /spdk/lib/nvmf/rdma.c (revision a83f91c29a4740e4bea5f9509b7036e9e7dc2788)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation.
5  *   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/assert.h"
44 #include "spdk/thread.h"
45 #include "spdk/nvmf.h"
46 #include "spdk/nvmf_spec.h"
47 #include "spdk/string.h"
48 #include "spdk/trace.h"
49 #include "spdk/util.h"
50 
51 #include "spdk_internal/log.h"
52 
53 /*
54  RDMA Connection Resouce Defaults
55  */
56 #define NVMF_DEFAULT_TX_SGE		1
57 #define NVMF_DEFAULT_RX_SGE		2
58 #define NVMF_DEFAULT_DATA_SGE		16
59 
60 /* The RDMA completion queue size */
61 #define NVMF_RDMA_CQ_SIZE	4096
62 
63 /* AIO backend requires block size aligned data buffers,
64  * extra 4KiB aligned data buffer should work for most devices.
65  */
66 #define SHIFT_4KB			12
67 #define NVMF_DATA_BUFFER_ALIGNMENT	(1 << SHIFT_4KB)
68 #define NVMF_DATA_BUFFER_MASK		(NVMF_DATA_BUFFER_ALIGNMENT - 1)
69 
70 enum spdk_nvmf_rdma_request_state {
71 	/* The request is not currently in use */
72 	RDMA_REQUEST_STATE_FREE = 0,
73 
74 	/* Initial state when request first received */
75 	RDMA_REQUEST_STATE_NEW,
76 
77 	/* The request is queued until a data buffer is available. */
78 	RDMA_REQUEST_STATE_NEED_BUFFER,
79 
80 	/* The request is waiting on RDMA queue depth availability
81 	 * to transfer data from the host to the controller.
82 	 */
83 	RDMA_REQUEST_STATE_TRANSFER_PENDING_HOST_TO_CONTROLLER,
84 
85 	/* The request is currently transferring data from the host to the controller. */
86 	RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
87 
88 	/* The request is ready to execute at the block device */
89 	RDMA_REQUEST_STATE_READY_TO_EXECUTE,
90 
91 	/* The request is currently executing at the block device */
92 	RDMA_REQUEST_STATE_EXECUTING,
93 
94 	/* The request finished executing at the block device */
95 	RDMA_REQUEST_STATE_EXECUTED,
96 
97 	/* The request is waiting on RDMA queue depth availability
98 	 * to transfer data from the controller to the host.
99 	 */
100 	RDMA_REQUEST_STATE_TRANSFER_PENDING_CONTROLLER_TO_HOST,
101 
102 	/* The request is ready to send a completion */
103 	RDMA_REQUEST_STATE_READY_TO_COMPLETE,
104 
105 	/* The request currently has a completion outstanding */
106 	RDMA_REQUEST_STATE_COMPLETING,
107 
108 	/* The request completed and can be marked free. */
109 	RDMA_REQUEST_STATE_COMPLETED,
110 };
111 
112 /* This structure holds commands as they are received off the wire.
113  * It must be dynamically paired with a full request object
114  * (spdk_nvmf_rdma_request) to service a request. It is separate
115  * from the request because RDMA does not appear to order
116  * completions, so occasionally we'll get a new incoming
117  * command when there aren't any free request objects.
118  */
119 struct spdk_nvmf_rdma_recv {
120 	struct ibv_recv_wr		wr;
121 	struct ibv_sge			sgl[NVMF_DEFAULT_RX_SGE];
122 
123 	struct spdk_nvmf_rdma_qpair	*qpair;
124 
125 	/* In-capsule data buffer */
126 	uint8_t				*buf;
127 
128 	TAILQ_ENTRY(spdk_nvmf_rdma_recv) link;
129 };
130 
131 struct spdk_nvmf_rdma_request {
132 	struct spdk_nvmf_request		req;
133 	bool					data_from_pool;
134 
135 	enum spdk_nvmf_rdma_request_state	state;
136 
137 	struct spdk_nvmf_rdma_recv		*recv;
138 
139 	struct {
140 		struct	ibv_send_wr		wr;
141 		struct	ibv_sge			sgl[NVMF_DEFAULT_TX_SGE];
142 	} rsp;
143 
144 	struct {
145 		struct ibv_send_wr		wr;
146 		struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
147 		void				*buffers[SPDK_NVMF_MAX_SGL_ENTRIES];
148 	} data;
149 
150 	TAILQ_ENTRY(spdk_nvmf_rdma_request)	link;
151 };
152 
153 struct spdk_nvmf_rdma_qpair {
154 	struct spdk_nvmf_qpair			qpair;
155 
156 	struct spdk_nvmf_rdma_port		*port;
157 	struct spdk_nvmf_rdma_poller		*poller;
158 
159 	struct rdma_cm_id			*cm_id;
160 
161 	/* The maximum number of I/O outstanding on this connection at one time */
162 	uint16_t				max_queue_depth;
163 
164 	/* The maximum number of active RDMA READ and WRITE operations at one time */
165 	uint16_t				max_rw_depth;
166 
167 	/* The current number of I/O outstanding on this connection. This number
168 	 * includes all I/O from the time the capsule is first received until it is
169 	 * completed.
170 	 */
171 	uint16_t				cur_queue_depth;
172 
173 	/* The number of RDMA READ and WRITE requests that are outstanding */
174 	uint16_t				cur_rdma_rw_depth;
175 
176 	/* Receives that are waiting for a request object */
177 	TAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
178 
179 	/* Requests that are not in use */
180 	TAILQ_HEAD(, spdk_nvmf_rdma_request)	free_queue;
181 
182 	/* Requests that are waiting to perform an RDMA READ or WRITE */
183 	TAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_rw_queue;
184 
185 	/* Array of size "max_queue_depth" containing RDMA requests. */
186 	struct spdk_nvmf_rdma_request		*reqs;
187 
188 	/* Array of size "max_queue_depth" containing RDMA recvs. */
189 	struct spdk_nvmf_rdma_recv		*recvs;
190 
191 	/* Array of size "max_queue_depth" containing 64 byte capsules
192 	 * used for receive.
193 	 */
194 	union nvmf_h2c_msg			*cmds;
195 	struct ibv_mr				*cmds_mr;
196 
197 	/* Array of size "max_queue_depth" containing 16 byte completions
198 	 * to be sent back to the user.
199 	 */
200 	union nvmf_c2h_msg			*cpls;
201 	struct ibv_mr				*cpls_mr;
202 
203 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
204 	 * buffers to be used for in capsule data.
205 	 */
206 	void					*bufs;
207 	struct ibv_mr				*bufs_mr;
208 
209 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	link;
210 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	pending_link;
211 
212 	/* Mgmt channel */
213 	struct spdk_io_channel			*mgmt_channel;
214 	struct spdk_nvmf_rdma_mgmt_channel	*ch;
215 };
216 
217 struct spdk_nvmf_rdma_poller {
218 	struct spdk_nvmf_rdma_device		*device;
219 	struct spdk_nvmf_rdma_poll_group	*group;
220 
221 	struct ibv_cq				*cq;
222 
223 	TAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs;
224 
225 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
226 };
227 
228 struct spdk_nvmf_rdma_poll_group {
229 	struct spdk_nvmf_transport_poll_group	group;
230 
231 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)	pollers;
232 };
233 
234 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
235 struct spdk_nvmf_rdma_device {
236 	struct ibv_device_attr			attr;
237 	struct ibv_context			*context;
238 
239 	struct spdk_mem_map			*map;
240 	struct ibv_pd				*pd;
241 
242 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
243 };
244 
245 struct spdk_nvmf_rdma_port {
246 	struct spdk_nvme_transport_id		trid;
247 	struct rdma_cm_id			*id;
248 	struct spdk_nvmf_rdma_device		*device;
249 	uint32_t				ref;
250 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
251 };
252 
253 struct spdk_nvmf_rdma_transport {
254 	struct spdk_nvmf_transport	transport;
255 
256 	struct rdma_event_channel	*event_channel;
257 
258 	struct spdk_mempool		*data_buf_pool;
259 
260 	pthread_mutex_t			lock;
261 
262 	uint16_t			max_queue_depth;
263 	uint32_t			max_io_size;
264 	uint32_t			io_unit_size;
265 	uint32_t			in_capsule_data_size;
266 
267 	/* fields used to poll RDMA/IB events */
268 	nfds_t			npoll_fds;
269 	struct pollfd		*poll_fds;
270 
271 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
272 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
273 };
274 
275 struct spdk_nvmf_rdma_mgmt_channel {
276 	/* Requests that are waiting to obtain a data buffer */
277 	TAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_data_buf_queue;
278 };
279 
280 static int
281 spdk_nvmf_rdma_mgmt_channel_create(void *io_device, void *ctx_buf)
282 {
283 	struct spdk_nvmf_rdma_mgmt_channel *ch = ctx_buf;
284 
285 	TAILQ_INIT(&ch->pending_data_buf_queue);
286 	return 0;
287 }
288 
289 static void
290 spdk_nvmf_rdma_mgmt_channel_destroy(void *io_device, void *ctx_buf)
291 {
292 	struct spdk_nvmf_rdma_mgmt_channel *ch = ctx_buf;
293 
294 	if (!TAILQ_EMPTY(&ch->pending_data_buf_queue)) {
295 		SPDK_ERRLOG("Pending I/O list wasn't empty on channel destruction\n");
296 	}
297 }
298 
299 static void
300 spdk_nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
301 {
302 	if (rqpair->poller) {
303 		TAILQ_REMOVE(&rqpair->poller->qpairs, rqpair, link);
304 	}
305 
306 	if (rqpair->cmds_mr) {
307 		ibv_dereg_mr(rqpair->cmds_mr);
308 	}
309 
310 	if (rqpair->cpls_mr) {
311 		ibv_dereg_mr(rqpair->cpls_mr);
312 	}
313 
314 	if (rqpair->bufs_mr) {
315 		ibv_dereg_mr(rqpair->bufs_mr);
316 	}
317 
318 	if (rqpair->cm_id) {
319 		rdma_destroy_qp(rqpair->cm_id);
320 		rdma_destroy_id(rqpair->cm_id);
321 	}
322 
323 	if (rqpair->mgmt_channel) {
324 		spdk_put_io_channel(rqpair->mgmt_channel);
325 	}
326 
327 	/* Free all memory */
328 	spdk_dma_free(rqpair->cmds);
329 	spdk_dma_free(rqpair->cpls);
330 	spdk_dma_free(rqpair->bufs);
331 	free(rqpair->reqs);
332 	free(rqpair->recvs);
333 	free(rqpair);
334 }
335 
336 static int
337 spdk_nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
338 {
339 	struct spdk_nvmf_rdma_transport *rtransport;
340 	struct spdk_nvmf_rdma_qpair	*rqpair;
341 	int				rc, i;
342 	struct ibv_qp_init_attr		attr;
343 	struct spdk_nvmf_rdma_recv	*rdma_recv;
344 	struct spdk_nvmf_rdma_request	*rdma_req;
345 
346 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
347 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
348 
349 	memset(&attr, 0, sizeof(struct ibv_qp_init_attr));
350 	attr.qp_type		= IBV_QPT_RC;
351 	attr.send_cq		= rqpair->poller->cq;
352 	attr.recv_cq		= rqpair->poller->cq;
353 	attr.cap.max_send_wr	= rqpair->max_queue_depth * 2; /* SEND, READ, and WRITE operations */
354 	attr.cap.max_recv_wr	= rqpair->max_queue_depth; /* RECV operations */
355 	attr.cap.max_send_sge	= SPDK_NVMF_MAX_SGL_ENTRIES;
356 	attr.cap.max_recv_sge	= NVMF_DEFAULT_RX_SGE;
357 
358 	rc = rdma_create_qp(rqpair->cm_id, NULL, &attr);
359 	if (rc) {
360 		SPDK_ERRLOG("rdma_create_qp failed: errno %d: %s\n", errno, spdk_strerror(errno));
361 		rdma_destroy_id(rqpair->cm_id);
362 		rqpair->cm_id = NULL;
363 		spdk_nvmf_rdma_qpair_destroy(rqpair);
364 		return -1;
365 	}
366 
367 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "New RDMA Connection: %p\n", qpair);
368 
369 	rqpair->reqs = calloc(rqpair->max_queue_depth, sizeof(*rqpair->reqs));
370 	rqpair->recvs = calloc(rqpair->max_queue_depth, sizeof(*rqpair->recvs));
371 	rqpair->cmds = spdk_dma_zmalloc(rqpair->max_queue_depth * sizeof(*rqpair->cmds),
372 					0x1000, NULL);
373 	rqpair->cpls = spdk_dma_zmalloc(rqpair->max_queue_depth * sizeof(*rqpair->cpls),
374 					0x1000, NULL);
375 	rqpair->bufs = spdk_dma_zmalloc(rqpair->max_queue_depth * rtransport->in_capsule_data_size,
376 					0x1000, NULL);
377 	if (!rqpair->reqs || !rqpair->recvs || !rqpair->cmds ||
378 	    !rqpair->cpls || !rqpair->bufs) {
379 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
380 		spdk_nvmf_rdma_qpair_destroy(rqpair);
381 		return -1;
382 	}
383 
384 	rqpair->cmds_mr = ibv_reg_mr(rqpair->cm_id->pd, rqpair->cmds,
385 				     rqpair->max_queue_depth * sizeof(*rqpair->cmds),
386 				     IBV_ACCESS_LOCAL_WRITE);
387 	rqpair->cpls_mr = ibv_reg_mr(rqpair->cm_id->pd, rqpair->cpls,
388 				     rqpair->max_queue_depth * sizeof(*rqpair->cpls),
389 				     0);
390 	rqpair->bufs_mr = ibv_reg_mr(rqpair->cm_id->pd, rqpair->bufs,
391 				     rqpair->max_queue_depth * rtransport->in_capsule_data_size,
392 				     IBV_ACCESS_LOCAL_WRITE |
393 				     IBV_ACCESS_REMOTE_WRITE);
394 	if (!rqpair->cmds_mr || !rqpair->cpls_mr || !rqpair->bufs_mr) {
395 		SPDK_ERRLOG("Unable to register required memory for RDMA queue.\n");
396 		spdk_nvmf_rdma_qpair_destroy(rqpair);
397 		return -1;
398 	}
399 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Command Array: %p Length: %lx LKey: %x\n",
400 		      rqpair->cmds, rqpair->max_queue_depth * sizeof(*rqpair->cmds), rqpair->cmds_mr->lkey);
401 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Completion Array: %p Length: %lx LKey: %x\n",
402 		      rqpair->cpls, rqpair->max_queue_depth * sizeof(*rqpair->cpls), rqpair->cpls_mr->lkey);
403 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "In Capsule Data Array: %p Length: %x LKey: %x\n",
404 		      rqpair->bufs, rqpair->max_queue_depth * rtransport->in_capsule_data_size, rqpair->bufs_mr->lkey);
405 
406 	for (i = 0; i < rqpair->max_queue_depth; i++) {
407 		struct ibv_recv_wr *bad_wr = NULL;
408 
409 		rdma_recv = &rqpair->recvs[i];
410 		rdma_recv->qpair = rqpair;
411 
412 		/* Set up memory to receive commands */
413 		rdma_recv->buf = (void *)((uintptr_t)rqpair->bufs + (i * rtransport->in_capsule_data_size));
414 
415 		rdma_recv->sgl[0].addr = (uintptr_t)&rqpair->cmds[i];
416 		rdma_recv->sgl[0].length = sizeof(rqpair->cmds[i]);
417 		rdma_recv->sgl[0].lkey = rqpair->cmds_mr->lkey;
418 
419 		rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
420 		rdma_recv->sgl[1].length = rtransport->in_capsule_data_size;
421 		rdma_recv->sgl[1].lkey = rqpair->bufs_mr->lkey;
422 
423 		rdma_recv->wr.wr_id = (uintptr_t)rdma_recv;
424 		rdma_recv->wr.sg_list = rdma_recv->sgl;
425 		rdma_recv->wr.num_sge = SPDK_COUNTOF(rdma_recv->sgl);
426 
427 		rc = ibv_post_recv(rqpair->cm_id->qp, &rdma_recv->wr, &bad_wr);
428 		if (rc) {
429 			SPDK_ERRLOG("Unable to post capsule for RDMA RECV\n");
430 			spdk_nvmf_rdma_qpair_destroy(rqpair);
431 			return -1;
432 		}
433 	}
434 
435 	for (i = 0; i < rqpair->max_queue_depth; i++) {
436 		rdma_req = &rqpair->reqs[i];
437 
438 		rdma_req->req.qpair = &rqpair->qpair;
439 		rdma_req->req.cmd = NULL;
440 
441 		/* Set up memory to send responses */
442 		rdma_req->req.rsp = &rqpair->cpls[i];
443 
444 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&rqpair->cpls[i];
445 		rdma_req->rsp.sgl[0].length = sizeof(rqpair->cpls[i]);
446 		rdma_req->rsp.sgl[0].lkey = rqpair->cpls_mr->lkey;
447 
448 		rdma_req->rsp.wr.wr_id = (uintptr_t)rdma_req;
449 		rdma_req->rsp.wr.next = NULL;
450 		rdma_req->rsp.wr.opcode = IBV_WR_SEND;
451 		rdma_req->rsp.wr.send_flags = IBV_SEND_SIGNALED;
452 		rdma_req->rsp.wr.sg_list = rdma_req->rsp.sgl;
453 		rdma_req->rsp.wr.num_sge = SPDK_COUNTOF(rdma_req->rsp.sgl);
454 
455 		/* Set up memory for data buffers */
456 		rdma_req->data.wr.wr_id = (uint64_t)rdma_req;
457 		rdma_req->data.wr.next = NULL;
458 		rdma_req->data.wr.send_flags = IBV_SEND_SIGNALED;
459 		rdma_req->data.wr.sg_list = rdma_req->data.sgl;
460 		rdma_req->data.wr.num_sge = SPDK_COUNTOF(rdma_req->data.sgl);
461 
462 		TAILQ_INSERT_TAIL(&rqpair->free_queue, rdma_req, link);
463 	}
464 
465 	return 0;
466 }
467 
468 static int
469 request_transfer_in(struct spdk_nvmf_request *req)
470 {
471 	int				rc;
472 	struct spdk_nvmf_rdma_request	*rdma_req;
473 	struct spdk_nvmf_qpair		*qpair;
474 	struct spdk_nvmf_rdma_qpair	*rqpair;
475 	struct ibv_send_wr		*bad_wr = NULL;
476 
477 	qpair = req->qpair;
478 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
479 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
480 
481 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
482 
483 	rqpair->cur_rdma_rw_depth++;
484 
485 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA READ POSTED. Request: %p Connection: %p\n", req, qpair);
486 	spdk_trace_record(TRACE_RDMA_READ_START, 0, 0, (uintptr_t)req, 0);
487 
488 	rdma_req->data.wr.opcode = IBV_WR_RDMA_READ;
489 	rdma_req->data.wr.next = NULL;
490 	rc = ibv_post_send(rqpair->cm_id->qp, &rdma_req->data.wr, &bad_wr);
491 	if (rc) {
492 		SPDK_ERRLOG("Unable to transfer data from host to target\n");
493 
494 		/* Decrement r/w counter back since data transfer
495 		 * has not started.
496 		 */
497 		rqpair->cur_rdma_rw_depth--;
498 		return -1;
499 	}
500 
501 	return 0;
502 }
503 
504 static int
505 request_transfer_out(struct spdk_nvmf_request *req)
506 {
507 	int				rc;
508 	struct spdk_nvmf_rdma_request	*rdma_req;
509 	struct spdk_nvmf_qpair		*qpair;
510 	struct spdk_nvmf_rdma_qpair	*rqpair;
511 	struct spdk_nvme_cpl		*rsp;
512 	struct ibv_recv_wr		*bad_recv_wr = NULL;
513 	struct ibv_send_wr		*send_wr, *bad_send_wr = NULL;
514 
515 	qpair = req->qpair;
516 	rsp = &req->rsp->nvme_cpl;
517 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
518 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
519 
520 	/* Advance our sq_head pointer */
521 	if (qpair->sq_head == qpair->sq_head_max) {
522 		qpair->sq_head = 0;
523 	} else {
524 		qpair->sq_head++;
525 	}
526 	rsp->sqhd = qpair->sq_head;
527 
528 	/* Post the capsule to the recv buffer */
529 	assert(rdma_req->recv != NULL);
530 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA RECV POSTED. Recv: %p Connection: %p\n", rdma_req->recv,
531 		      rqpair);
532 	rc = ibv_post_recv(rqpair->cm_id->qp, &rdma_req->recv->wr, &bad_recv_wr);
533 	if (rc) {
534 		SPDK_ERRLOG("Unable to re-post rx descriptor\n");
535 		return rc;
536 	}
537 	rdma_req->recv = NULL;
538 
539 	/* Build the response which consists of an optional
540 	 * RDMA WRITE to transfer data, plus an RDMA SEND
541 	 * containing the response.
542 	 */
543 	send_wr = &rdma_req->rsp.wr;
544 
545 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
546 	    req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
547 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA WRITE POSTED. Request: %p Connection: %p\n", req, qpair);
548 		spdk_trace_record(TRACE_RDMA_WRITE_START, 0, 0, (uintptr_t)req, 0);
549 
550 		rqpair->cur_rdma_rw_depth++;
551 		rdma_req->data.wr.opcode = IBV_WR_RDMA_WRITE;
552 
553 		rdma_req->data.wr.next = send_wr;
554 		send_wr = &rdma_req->data.wr;
555 	}
556 
557 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "RDMA SEND POSTED. Request: %p Connection: %p\n", req, qpair);
558 	spdk_trace_record(TRACE_NVMF_IO_COMPLETE, 0, 0, (uintptr_t)req, 0);
559 
560 	/* Send the completion */
561 	rc = ibv_post_send(rqpair->cm_id->qp, send_wr, &bad_send_wr);
562 	if (rc) {
563 		SPDK_ERRLOG("Unable to send response capsule\n");
564 
565 		if (rdma_req->data.wr.opcode == IBV_WR_RDMA_WRITE) {
566 			/* Decrement r/w counter back since data transfer
567 			 * has not started.
568 			 */
569 			rqpair->cur_rdma_rw_depth--;
570 		}
571 	}
572 
573 	return rc;
574 }
575 
576 static int
577 spdk_nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
578 {
579 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
580 	struct rdma_conn_param				ctrlr_event_data = {};
581 	int						rc;
582 
583 	accept_data.recfmt = 0;
584 	accept_data.crqsize = rqpair->max_queue_depth;
585 
586 	ctrlr_event_data.private_data = &accept_data;
587 	ctrlr_event_data.private_data_len = sizeof(accept_data);
588 	if (id->ps == RDMA_PS_TCP) {
589 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
590 		ctrlr_event_data.initiator_depth = rqpair->max_rw_depth;
591 	}
592 
593 	rc = rdma_accept(id, &ctrlr_event_data);
594 	if (rc) {
595 		SPDK_ERRLOG("Error %d on rdma_accept\n", errno);
596 	} else {
597 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Sent back the accept\n");
598 	}
599 
600 	return rc;
601 }
602 
603 static void
604 spdk_nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
605 {
606 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
607 
608 	rej_data.recfmt = 0;
609 	rej_data.sts = error;
610 
611 	rdma_reject(id, &rej_data, sizeof(rej_data));
612 }
613 
614 static int
615 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event,
616 		  new_qpair_fn cb_fn)
617 {
618 	struct spdk_nvmf_rdma_transport *rtransport;
619 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
620 	struct spdk_nvmf_rdma_port	*port;
621 	struct rdma_conn_param		*rdma_param = NULL;
622 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
623 	uint16_t			max_queue_depth;
624 	uint16_t			max_rw_depth;
625 
626 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
627 
628 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
629 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
630 
631 	rdma_param = &event->param.conn;
632 	if (rdma_param->private_data == NULL ||
633 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
634 		SPDK_ERRLOG("connect request: no private data provided\n");
635 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
636 		return -1;
637 	}
638 
639 	private_data = rdma_param->private_data;
640 	if (private_data->recfmt != 0) {
641 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
642 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
643 		return -1;
644 	}
645 
646 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Connect Recv on fabric intf name %s, dev_name %s\n",
647 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
648 
649 	port = event->listen_id->context;
650 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
651 		      event->listen_id, event->listen_id->verbs, port);
652 
653 	/* Figure out the supported queue depth. This is a multi-step process
654 	 * that takes into account hardware maximums, host provided values,
655 	 * and our target's internal memory limits */
656 
657 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Calculating Queue Depth\n");
658 
659 	/* Start with the maximum queue depth allowed by the target */
660 	max_queue_depth = rtransport->max_queue_depth;
661 	max_rw_depth = rtransport->max_queue_depth;
662 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Target Max Queue Depth: %d\n", rtransport->max_queue_depth);
663 
664 	/* Next check the local NIC's hardware limitations */
665 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
666 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
667 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
668 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
669 	max_rw_depth = spdk_min(max_rw_depth, port->device->attr.max_qp_rd_atom);
670 
671 	/* Next check the remote NIC's hardware limitations */
672 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
673 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
674 		      rdma_param->initiator_depth, rdma_param->responder_resources);
675 	if (rdma_param->initiator_depth > 0) {
676 		max_rw_depth = spdk_min(max_rw_depth, rdma_param->initiator_depth);
677 	}
678 
679 	/* Finally check for the host software requested values, which are
680 	 * optional. */
681 	if (rdma_param->private_data != NULL &&
682 	    rdma_param->private_data_len >= sizeof(struct spdk_nvmf_rdma_request_private_data)) {
683 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Receive Queue Size: %d\n", private_data->hrqsize);
684 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Send Queue Size: %d\n", private_data->hsqsize);
685 		max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
686 		max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
687 	}
688 
689 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
690 		      max_queue_depth, max_rw_depth);
691 
692 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
693 	if (rqpair == NULL) {
694 		SPDK_ERRLOG("Could not allocate new connection.\n");
695 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
696 		return -1;
697 	}
698 
699 	rqpair->port = port;
700 	rqpair->max_queue_depth = max_queue_depth;
701 	rqpair->max_rw_depth = max_rw_depth;
702 	rqpair->cm_id = event->id;
703 	rqpair->qpair.transport = transport;
704 	TAILQ_INIT(&rqpair->incoming_queue);
705 	TAILQ_INIT(&rqpair->free_queue);
706 	TAILQ_INIT(&rqpair->pending_rdma_rw_queue);
707 
708 	event->id->context = &rqpair->qpair;
709 
710 	cb_fn(&rqpair->qpair);
711 
712 	return 0;
713 }
714 
715 static int
716 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
717 {
718 	struct spdk_nvmf_qpair		*qpair;
719 
720 	if (evt->id == NULL) {
721 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
722 		return -1;
723 	}
724 
725 	qpair = evt->id->context;
726 	if (qpair == NULL) {
727 		SPDK_ERRLOG("disconnect request: no active connection\n");
728 		return -1;
729 	}
730 	/* ack the disconnect event before rdma_destroy_id */
731 	rdma_ack_cm_event(evt);
732 
733 	spdk_nvmf_ctrlr_disconnect(qpair);
734 
735 	return 0;
736 }
737 
738 #ifdef DEBUG
739 static const char *CM_EVENT_STR[] = {
740 	"RDMA_CM_EVENT_ADDR_RESOLVED",
741 	"RDMA_CM_EVENT_ADDR_ERROR",
742 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
743 	"RDMA_CM_EVENT_ROUTE_ERROR",
744 	"RDMA_CM_EVENT_CONNECT_REQUEST",
745 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
746 	"RDMA_CM_EVENT_CONNECT_ERROR",
747 	"RDMA_CM_EVENT_UNREACHABLE",
748 	"RDMA_CM_EVENT_REJECTED",
749 	"RDMA_CM_EVENT_ESTABLISHED",
750 	"RDMA_CM_EVENT_DISCONNECTED",
751 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
752 	"RDMA_CM_EVENT_MULTICAST_JOIN",
753 	"RDMA_CM_EVENT_MULTICAST_ERROR",
754 	"RDMA_CM_EVENT_ADDR_CHANGE",
755 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
756 };
757 #endif /* DEBUG */
758 
759 static int
760 spdk_nvmf_rdma_mem_notify(void *cb_ctx, struct spdk_mem_map *map,
761 			  enum spdk_mem_map_notify_action action,
762 			  void *vaddr, size_t size)
763 {
764 	struct spdk_nvmf_rdma_device *device = cb_ctx;
765 	struct ibv_pd *pd = device->pd;
766 	struct ibv_mr *mr;
767 
768 	switch (action) {
769 	case SPDK_MEM_MAP_NOTIFY_REGISTER:
770 		mr = ibv_reg_mr(pd, vaddr, size,
771 				IBV_ACCESS_LOCAL_WRITE |
772 				IBV_ACCESS_REMOTE_READ |
773 				IBV_ACCESS_REMOTE_WRITE);
774 		if (mr == NULL) {
775 			SPDK_ERRLOG("ibv_reg_mr() failed\n");
776 			return -1;
777 		} else {
778 			spdk_mem_map_set_translation(map, (uint64_t)vaddr, size, (uint64_t)mr);
779 		}
780 		break;
781 	case SPDK_MEM_MAP_NOTIFY_UNREGISTER:
782 		mr = (struct ibv_mr *)spdk_mem_map_translate(map, (uint64_t)vaddr, size);
783 		spdk_mem_map_clear_translation(map, (uint64_t)vaddr, size);
784 		if (mr) {
785 			ibv_dereg_mr(mr);
786 		}
787 		break;
788 	}
789 
790 	return 0;
791 }
792 
793 typedef enum spdk_nvme_data_transfer spdk_nvme_data_transfer_t;
794 
795 static spdk_nvme_data_transfer_t
796 spdk_nvmf_rdma_request_get_xfer(struct spdk_nvmf_rdma_request *rdma_req)
797 {
798 	enum spdk_nvme_data_transfer xfer;
799 	struct spdk_nvme_cmd *cmd = &rdma_req->req.cmd->nvme_cmd;
800 	struct spdk_nvme_sgl_descriptor *sgl = &cmd->dptr.sgl1;
801 
802 	/* Figure out data transfer direction */
803 	if (cmd->opc == SPDK_NVME_OPC_FABRIC) {
804 		xfer = spdk_nvme_opc_get_data_transfer(rdma_req->req.cmd->nvmf_cmd.fctype);
805 	} else {
806 		xfer = spdk_nvme_opc_get_data_transfer(cmd->opc);
807 
808 		/* Some admin commands are special cases */
809 		if ((rdma_req->req.qpair->qid == 0) &&
810 		    ((cmd->opc == SPDK_NVME_OPC_GET_FEATURES) ||
811 		     (cmd->opc == SPDK_NVME_OPC_SET_FEATURES))) {
812 			switch (cmd->cdw10 & 0xff) {
813 			case SPDK_NVME_FEAT_LBA_RANGE_TYPE:
814 			case SPDK_NVME_FEAT_AUTONOMOUS_POWER_STATE_TRANSITION:
815 			case SPDK_NVME_FEAT_HOST_IDENTIFIER:
816 				break;
817 			default:
818 				xfer = SPDK_NVME_DATA_NONE;
819 			}
820 		}
821 	}
822 
823 	if (xfer == SPDK_NVME_DATA_NONE) {
824 		return xfer;
825 	}
826 
827 	/* Even for commands that may transfer data, they could have specified 0 length.
828 	 * We want those to show up with xfer SPDK_NVME_DATA_NONE.
829 	 */
830 	switch (sgl->generic.type) {
831 	case SPDK_NVME_SGL_TYPE_DATA_BLOCK:
832 	case SPDK_NVME_SGL_TYPE_BIT_BUCKET:
833 	case SPDK_NVME_SGL_TYPE_SEGMENT:
834 	case SPDK_NVME_SGL_TYPE_LAST_SEGMENT:
835 	case SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK:
836 		if (sgl->unkeyed.length == 0) {
837 			xfer = SPDK_NVME_DATA_NONE;
838 		}
839 		break;
840 	case SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK:
841 		if (sgl->keyed.length == 0) {
842 			xfer = SPDK_NVME_DATA_NONE;
843 		}
844 		break;
845 	}
846 
847 	return xfer;
848 }
849 
850 static int
851 spdk_nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
852 				 struct spdk_nvmf_rdma_device *device,
853 				 struct spdk_nvmf_rdma_request *rdma_req)
854 {
855 	void		*buf = NULL;
856 	uint32_t	length = rdma_req->req.length;
857 	uint32_t	i = 0;
858 
859 	rdma_req->req.iovcnt = 0;
860 	while (length) {
861 		buf = spdk_mempool_get(rtransport->data_buf_pool);
862 		if (!buf) {
863 			goto nomem;
864 		}
865 
866 		rdma_req->req.iov[i].iov_base = (void *)((uintptr_t)(buf + NVMF_DATA_BUFFER_MASK) &
867 						~NVMF_DATA_BUFFER_MASK);
868 		rdma_req->req.iov[i].iov_len  = spdk_min(length, rtransport->io_unit_size);
869 		rdma_req->req.iovcnt++;
870 		rdma_req->data.buffers[i] = buf;
871 		rdma_req->data.wr.sg_list[i].addr = (uintptr_t)(rdma_req->req.iov[i].iov_base);
872 		rdma_req->data.wr.sg_list[i].length = rdma_req->req.iov[i].iov_len;
873 		rdma_req->data.wr.sg_list[i].lkey = ((struct ibv_mr *)spdk_mem_map_translate(device->map,
874 						     (uint64_t)buf, rdma_req->req.iov[i].iov_len))->lkey;
875 
876 		length -= rdma_req->req.iov[i].iov_len;
877 		i++;
878 	}
879 
880 	rdma_req->data_from_pool = true;
881 
882 	return 0;
883 
884 nomem:
885 	while (i) {
886 		i--;
887 		spdk_mempool_put(rtransport->data_buf_pool, rdma_req->req.iov[i].iov_base);
888 		rdma_req->req.iov[i].iov_base = NULL;
889 		rdma_req->req.iov[i].iov_len = 0;
890 
891 		rdma_req->data.wr.sg_list[i].addr = 0;
892 		rdma_req->data.wr.sg_list[i].length = 0;
893 		rdma_req->data.wr.sg_list[i].lkey = 0;
894 	}
895 	rdma_req->req.iovcnt = 0;
896 	return -ENOMEM;
897 }
898 
899 static int
900 spdk_nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
901 				 struct spdk_nvmf_rdma_device *device,
902 				 struct spdk_nvmf_rdma_request *rdma_req)
903 {
904 	struct spdk_nvme_cmd			*cmd;
905 	struct spdk_nvme_cpl			*rsp;
906 	struct spdk_nvme_sgl_descriptor		*sgl;
907 
908 	cmd = &rdma_req->req.cmd->nvme_cmd;
909 	rsp = &rdma_req->req.rsp->nvme_cpl;
910 	sgl = &cmd->dptr.sgl1;
911 
912 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
913 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
914 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
915 		if (sgl->keyed.length > rtransport->max_io_size) {
916 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
917 				    sgl->keyed.length, rtransport->max_io_size);
918 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
919 			return -1;
920 		}
921 
922 		/* fill request length and populate iovs */
923 		rdma_req->req.length = sgl->keyed.length;
924 
925 		if (spdk_nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req) < 0) {
926 			/* No available buffers. Queue this request up. */
927 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
928 			return 0;
929 		}
930 
931 		/* backward compatible */
932 		rdma_req->req.data = rdma_req->req.iov[0].iov_base;
933 
934 		/* rdma wr specifics */
935 		rdma_req->data.wr.num_sge = rdma_req->req.iovcnt;
936 		rdma_req->data.wr.wr.rdma.rkey = sgl->keyed.key;
937 		rdma_req->data.wr.wr.rdma.remote_addr = sgl->address;
938 
939 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
940 			      rdma_req->req.iovcnt);
941 
942 		return 0;
943 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
944 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
945 		uint64_t offset = sgl->address;
946 		uint32_t max_len = rtransport->in_capsule_data_size;
947 
948 		SPDK_DEBUGLOG(SPDK_LOG_NVMF, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
949 			      offset, sgl->unkeyed.length);
950 
951 		if (offset > max_len) {
952 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
953 				    offset, max_len);
954 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
955 			return -1;
956 		}
957 		max_len -= (uint32_t)offset;
958 
959 		if (sgl->unkeyed.length > max_len) {
960 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
961 				    sgl->unkeyed.length, max_len);
962 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
963 			return -1;
964 		}
965 
966 		rdma_req->req.data = rdma_req->recv->buf + offset;
967 		rdma_req->data_from_pool = false;
968 		rdma_req->req.length = sgl->unkeyed.length;
969 
970 		rdma_req->req.iov[0].iov_base = rdma_req->req.data;
971 		rdma_req->req.iov[0].iov_len = rdma_req->req.length;
972 		rdma_req->req.iovcnt = 1;
973 
974 		return 0;
975 	}
976 
977 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
978 		    sgl->generic.type, sgl->generic.subtype);
979 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
980 	return -1;
981 }
982 
983 static bool
984 spdk_nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
985 			       struct spdk_nvmf_rdma_request *rdma_req)
986 {
987 	struct spdk_nvmf_rdma_qpair	*rqpair;
988 	struct spdk_nvmf_rdma_device	*device;
989 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
990 	int				rc;
991 	struct spdk_nvmf_rdma_recv	*rdma_recv;
992 	enum spdk_nvmf_rdma_request_state prev_state;
993 	bool				progress = false;
994 
995 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
996 	device = rqpair->port->device;
997 
998 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
999 
1000 	/* The loop here is to allow for several back-to-back state changes. */
1001 	do {
1002 		prev_state = rdma_req->state;
1003 
1004 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p entering state %d\n", rdma_req, prev_state);
1005 
1006 		switch (rdma_req->state) {
1007 		case RDMA_REQUEST_STATE_FREE:
1008 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
1009 			 * to escape this state. */
1010 			break;
1011 		case RDMA_REQUEST_STATE_NEW:
1012 			rqpair->cur_queue_depth++;
1013 			rdma_recv = rdma_req->recv;
1014 
1015 			/* The first element of the SGL is the NVMe command */
1016 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
1017 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
1018 
1019 			TAILQ_REMOVE(&rqpair->incoming_queue, rdma_recv, link);
1020 			TAILQ_REMOVE(&rqpair->free_queue, rdma_req, link);
1021 
1022 			/* The next state transition depends on the data transfer needs of this request. */
1023 			rdma_req->req.xfer = spdk_nvmf_rdma_request_get_xfer(rdma_req);
1024 
1025 			/* If no data to transfer, ready to execute. */
1026 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
1027 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1028 				break;
1029 			}
1030 
1031 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
1032 			TAILQ_INSERT_TAIL(&rqpair->ch->pending_data_buf_queue, rdma_req, link);
1033 			break;
1034 		case RDMA_REQUEST_STATE_NEED_BUFFER:
1035 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
1036 
1037 			if (rdma_req != TAILQ_FIRST(&rqpair->ch->pending_data_buf_queue)) {
1038 				/* This request needs to wait in line to obtain a buffer */
1039 				break;
1040 			}
1041 
1042 			/* Try to get a data buffer */
1043 			rc = spdk_nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
1044 			if (rc < 0) {
1045 				TAILQ_REMOVE(&rqpair->ch->pending_data_buf_queue, rdma_req, link);
1046 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
1047 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1048 				break;
1049 			}
1050 
1051 			if (!rdma_req->req.data) {
1052 				/* No buffers available. */
1053 				break;
1054 			}
1055 
1056 			TAILQ_REMOVE(&rqpair->ch->pending_data_buf_queue, rdma_req, link);
1057 
1058 			/* If data is transferring from host to controller and the data didn't
1059 			 * arrive using in capsule data, we need to do a transfer from the host.
1060 			 */
1061 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER && rdma_req->data_from_pool) {
1062 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFER_PENDING_HOST_TO_CONTROLLER;
1063 				TAILQ_INSERT_TAIL(&rqpair->pending_rdma_rw_queue, rdma_req, link);
1064 				break;
1065 			}
1066 
1067 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1068 			break;
1069 		case RDMA_REQUEST_STATE_TRANSFER_PENDING_HOST_TO_CONTROLLER:
1070 			if (rdma_req != TAILQ_FIRST(&rqpair->pending_rdma_rw_queue)) {
1071 				/* This request needs to wait in line to perform RDMA */
1072 				break;
1073 			}
1074 
1075 			if (rqpair->cur_rdma_rw_depth < rqpair->max_rw_depth) {
1076 				TAILQ_REMOVE(&rqpair->pending_rdma_rw_queue, rdma_req, link);
1077 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
1078 				rc = request_transfer_in(&rdma_req->req);
1079 				if (rc) {
1080 					rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
1081 					rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1082 				}
1083 			}
1084 			break;
1085 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
1086 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
1087 			 * to escape this state. */
1088 			break;
1089 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
1090 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
1091 			spdk_nvmf_request_exec(&rdma_req->req);
1092 			break;
1093 		case RDMA_REQUEST_STATE_EXECUTING:
1094 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
1095 			 * to escape this state. */
1096 			break;
1097 		case RDMA_REQUEST_STATE_EXECUTED:
1098 			if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1099 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFER_PENDING_CONTROLLER_TO_HOST;
1100 				TAILQ_INSERT_TAIL(&rqpair->pending_rdma_rw_queue, rdma_req, link);
1101 			} else {
1102 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1103 			}
1104 			break;
1105 		case RDMA_REQUEST_STATE_TRANSFER_PENDING_CONTROLLER_TO_HOST:
1106 			if (rdma_req != TAILQ_FIRST(&rqpair->pending_rdma_rw_queue)) {
1107 				/* This request needs to wait in line to perform RDMA */
1108 				break;
1109 			}
1110 
1111 			if (rqpair->cur_rdma_rw_depth < rqpair->max_rw_depth) {
1112 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
1113 				TAILQ_REMOVE(&rqpair->pending_rdma_rw_queue, rdma_req, link);
1114 			}
1115 			break;
1116 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
1117 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETING;
1118 
1119 			rc = request_transfer_out(&rdma_req->req);
1120 			assert(rc == 0); /* No good way to handle this currently */
1121 			break;
1122 		case RDMA_REQUEST_STATE_COMPLETING:
1123 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
1124 			 * to escape this state. */
1125 			break;
1126 		case RDMA_REQUEST_STATE_COMPLETED:
1127 			assert(rqpair->cur_queue_depth > 0);
1128 			rqpair->cur_queue_depth--;
1129 
1130 			if (rdma_req->data_from_pool) {
1131 				/* Put the buffer/s back in the pool */
1132 				for (uint32_t i = 0; i < rdma_req->req.iovcnt; i++) {
1133 					spdk_mempool_put(rtransport->data_buf_pool, rdma_req->data.buffers[i]);
1134 					rdma_req->req.iov[i].iov_base = NULL;
1135 					rdma_req->data.buffers[i] = NULL;
1136 				}
1137 				rdma_req->data_from_pool = false;
1138 			}
1139 			rdma_req->req.length = 0;
1140 			rdma_req->req.iovcnt = 0;
1141 			rdma_req->req.data = NULL;
1142 			rdma_req->state = RDMA_REQUEST_STATE_FREE;
1143 			TAILQ_INSERT_TAIL(&rqpair->free_queue, rdma_req, link);
1144 			break;
1145 		}
1146 
1147 		if (rdma_req->state != prev_state) {
1148 			progress = true;
1149 		}
1150 	} while (rdma_req->state != prev_state);
1151 
1152 	return progress;
1153 }
1154 
1155 /* Public API callbacks begin here */
1156 
1157 static struct spdk_nvmf_transport *
1158 spdk_nvmf_rdma_create(struct spdk_nvmf_tgt *tgt)
1159 {
1160 	int rc;
1161 	struct spdk_nvmf_rdma_transport *rtransport;
1162 	struct spdk_nvmf_rdma_device	*device, *tmp;
1163 	struct ibv_context		**contexts;
1164 	uint32_t			i;
1165 	int				flag;
1166 	uint32_t			sge_count;
1167 
1168 	rtransport = calloc(1, sizeof(*rtransport));
1169 	if (!rtransport) {
1170 		return NULL;
1171 	}
1172 
1173 	pthread_mutex_init(&rtransport->lock, NULL);
1174 	TAILQ_INIT(&rtransport->devices);
1175 	TAILQ_INIT(&rtransport->ports);
1176 
1177 	rtransport->transport.tgt = tgt;
1178 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
1179 
1180 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** RDMA Transport Init ***\n");
1181 
1182 	rtransport->max_queue_depth = tgt->opts.max_queue_depth;
1183 	rtransport->max_io_size = tgt->opts.max_io_size;
1184 	rtransport->io_unit_size = tgt->opts.io_unit_size;
1185 	rtransport->in_capsule_data_size = tgt->opts.in_capsule_data_size;
1186 
1187 	/* I/O unit size cannot be larger than max I/O size */
1188 	if (rtransport->io_unit_size > rtransport->max_io_size) {
1189 		rtransport->io_unit_size = rtransport->max_io_size;
1190 	}
1191 
1192 	sge_count = rtransport->max_io_size / rtransport->io_unit_size;
1193 	if (sge_count > SPDK_NVMF_MAX_SGL_ENTRIES) {
1194 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", rtransport->io_unit_size);
1195 		free(rtransport);
1196 		return NULL;
1197 	}
1198 
1199 	rtransport->event_channel = rdma_create_event_channel();
1200 	if (rtransport->event_channel == NULL) {
1201 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
1202 		free(rtransport);
1203 		return NULL;
1204 	}
1205 
1206 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
1207 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
1208 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
1209 			    rtransport->event_channel->fd, spdk_strerror(errno));
1210 		free(rtransport);
1211 		return NULL;
1212 	}
1213 
1214 	rtransport->data_buf_pool = spdk_mempool_create("spdk_nvmf_rdma",
1215 				    rtransport->max_queue_depth * 4, /* The 4 is arbitrarily chosen. Needs to be configurable. */
1216 				    rtransport->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT,
1217 				    SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
1218 				    SPDK_ENV_SOCKET_ID_ANY);
1219 	if (!rtransport->data_buf_pool) {
1220 		SPDK_ERRLOG("Unable to allocate buffer pool for poll group\n");
1221 		free(rtransport);
1222 		return NULL;
1223 	}
1224 
1225 	spdk_io_device_register(rtransport, spdk_nvmf_rdma_mgmt_channel_create,
1226 				spdk_nvmf_rdma_mgmt_channel_destroy,
1227 				sizeof(struct spdk_nvmf_rdma_mgmt_channel));
1228 
1229 	contexts = rdma_get_devices(NULL);
1230 	i = 0;
1231 	rc = 0;
1232 	while (contexts[i] != NULL) {
1233 		device = calloc(1, sizeof(*device));
1234 		if (!device) {
1235 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
1236 			rc = -ENOMEM;
1237 			break;
1238 		}
1239 		device->context = contexts[i];
1240 		rc = ibv_query_device(device->context, &device->attr);
1241 		if (rc < 0) {
1242 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
1243 			free(device);
1244 			break;
1245 
1246 		}
1247 		/* set up device context async ev fd as NON_BLOCKING */
1248 		flag = fcntl(device->context->async_fd, F_GETFL);
1249 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
1250 		if (rc < 0) {
1251 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
1252 			free(device);
1253 			break;
1254 		}
1255 
1256 		device->pd = NULL;
1257 		device->map = NULL;
1258 
1259 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
1260 		i++;
1261 	}
1262 
1263 	if (rc < 0) {
1264 		TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
1265 			TAILQ_REMOVE(&rtransport->devices, device, link);
1266 			free(device);
1267 		}
1268 		spdk_mempool_free(rtransport->data_buf_pool);
1269 		rdma_destroy_event_channel(rtransport->event_channel);
1270 		free(rtransport);
1271 		rdma_free_devices(contexts);
1272 		return NULL;
1273 	} else {
1274 		/* Set up poll descriptor array to monitor events from RDMA and IB
1275 		 * in a single poll syscall
1276 		 */
1277 		rtransport->npoll_fds = i + 1;
1278 		i = 0;
1279 		rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
1280 		rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
1281 		rtransport->poll_fds[i++].events = POLLIN;
1282 
1283 		TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
1284 			rtransport->poll_fds[i].fd = device->context->async_fd;
1285 			rtransport->poll_fds[i++].events = POLLIN;
1286 		}
1287 	}
1288 
1289 	rdma_free_devices(contexts);
1290 
1291 	return &rtransport->transport;
1292 }
1293 
1294 static int
1295 spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport)
1296 {
1297 	struct spdk_nvmf_rdma_transport	*rtransport;
1298 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
1299 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
1300 
1301 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1302 
1303 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
1304 		TAILQ_REMOVE(&rtransport->ports, port, link);
1305 		rdma_destroy_id(port->id);
1306 		free(port);
1307 	}
1308 
1309 	if (rtransport->poll_fds != NULL) {
1310 		free(rtransport->poll_fds);
1311 	}
1312 
1313 	if (rtransport->event_channel != NULL) {
1314 		rdma_destroy_event_channel(rtransport->event_channel);
1315 	}
1316 
1317 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
1318 		TAILQ_REMOVE(&rtransport->devices, device, link);
1319 		if (device->map) {
1320 			spdk_mem_map_free(&device->map);
1321 		}
1322 		free(device);
1323 	}
1324 
1325 	if (spdk_mempool_count(rtransport->data_buf_pool) != (rtransport->max_queue_depth * 4)) {
1326 		SPDK_ERRLOG("transport buffer pool count is %zu but should be %u\n",
1327 			    spdk_mempool_count(rtransport->data_buf_pool),
1328 			    rtransport->max_queue_depth * 4);
1329 	}
1330 
1331 	spdk_mempool_free(rtransport->data_buf_pool);
1332 	spdk_io_device_unregister(rtransport, NULL);
1333 	free(rtransport);
1334 
1335 	return 0;
1336 }
1337 
1338 static int
1339 spdk_nvmf_rdma_listen(struct spdk_nvmf_transport *transport,
1340 		      const struct spdk_nvme_transport_id *trid)
1341 {
1342 	struct spdk_nvmf_rdma_transport	*rtransport;
1343 	struct spdk_nvmf_rdma_device	*device;
1344 	struct spdk_nvmf_rdma_port	*port_tmp, *port;
1345 	struct addrinfo			*res;
1346 	struct addrinfo			hints;
1347 	int				family;
1348 	int				rc;
1349 
1350 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1351 
1352 	port = calloc(1, sizeof(*port));
1353 	if (!port) {
1354 		return -ENOMEM;
1355 	}
1356 
1357 	/* Selectively copy the trid. Things like NQN don't matter here - that
1358 	 * mapping is enforced elsewhere.
1359 	 */
1360 	port->trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
1361 	port->trid.adrfam = trid->adrfam;
1362 	snprintf(port->trid.traddr, sizeof(port->trid.traddr), "%s", trid->traddr);
1363 	snprintf(port->trid.trsvcid, sizeof(port->trid.trsvcid), "%s", trid->trsvcid);
1364 
1365 	pthread_mutex_lock(&rtransport->lock);
1366 	assert(rtransport->event_channel != NULL);
1367 	TAILQ_FOREACH(port_tmp, &rtransport->ports, link) {
1368 		if (spdk_nvme_transport_id_compare(&port_tmp->trid, &port->trid) == 0) {
1369 			port_tmp->ref++;
1370 			free(port);
1371 			/* Already listening at this address */
1372 			pthread_mutex_unlock(&rtransport->lock);
1373 			return 0;
1374 		}
1375 	}
1376 
1377 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
1378 	if (rc < 0) {
1379 		SPDK_ERRLOG("rdma_create_id() failed\n");
1380 		free(port);
1381 		pthread_mutex_unlock(&rtransport->lock);
1382 		return rc;
1383 	}
1384 
1385 	switch (port->trid.adrfam) {
1386 	case SPDK_NVMF_ADRFAM_IPV4:
1387 		family = AF_INET;
1388 		break;
1389 	case SPDK_NVMF_ADRFAM_IPV6:
1390 		family = AF_INET6;
1391 		break;
1392 	default:
1393 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", port->trid.adrfam);
1394 		free(port);
1395 		pthread_mutex_unlock(&rtransport->lock);
1396 		return -EINVAL;
1397 	}
1398 
1399 	memset(&hints, 0, sizeof(hints));
1400 	hints.ai_family = family;
1401 	hints.ai_socktype = SOCK_STREAM;
1402 	hints.ai_protocol = 0;
1403 
1404 	rc = getaddrinfo(port->trid.traddr, port->trid.trsvcid, &hints, &res);
1405 	if (rc) {
1406 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
1407 		free(port);
1408 		pthread_mutex_unlock(&rtransport->lock);
1409 		return -EINVAL;
1410 	}
1411 
1412 	rc = rdma_bind_addr(port->id, res->ai_addr);
1413 	freeaddrinfo(res);
1414 
1415 	if (rc < 0) {
1416 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
1417 		rdma_destroy_id(port->id);
1418 		free(port);
1419 		pthread_mutex_unlock(&rtransport->lock);
1420 		return rc;
1421 	}
1422 
1423 	rc = rdma_listen(port->id, 10); /* 10 = backlog */
1424 	if (rc < 0) {
1425 		SPDK_ERRLOG("rdma_listen() failed\n");
1426 		rdma_destroy_id(port->id);
1427 		free(port);
1428 		pthread_mutex_unlock(&rtransport->lock);
1429 		return rc;
1430 	}
1431 
1432 	TAILQ_FOREACH(device, &rtransport->devices, link) {
1433 		if (device->context == port->id->verbs) {
1434 			port->device = device;
1435 			break;
1436 		}
1437 	}
1438 	if (!port->device) {
1439 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
1440 			    port->id->verbs);
1441 		rdma_destroy_id(port->id);
1442 		free(port);
1443 		pthread_mutex_unlock(&rtransport->lock);
1444 		return -EINVAL;
1445 	}
1446 
1447 	if (!device->map) {
1448 		device->pd = port->id->pd;
1449 		device->map = spdk_mem_map_alloc(0, spdk_nvmf_rdma_mem_notify, device);
1450 		if (!device->map) {
1451 			SPDK_ERRLOG("Unable to allocate memory map for new poll group\n");
1452 			return -1;
1453 		}
1454 	} else {
1455 		assert(device->pd == port->id->pd);
1456 	}
1457 
1458 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** NVMf Target Listening on %s port %d ***\n",
1459 		     port->trid.traddr, ntohs(rdma_get_src_port(port->id)));
1460 
1461 	port->ref = 1;
1462 
1463 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
1464 	pthread_mutex_unlock(&rtransport->lock);
1465 
1466 	return 0;
1467 }
1468 
1469 static int
1470 spdk_nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
1471 			   const struct spdk_nvme_transport_id *_trid)
1472 {
1473 	struct spdk_nvmf_rdma_transport *rtransport;
1474 	struct spdk_nvmf_rdma_port *port, *tmp;
1475 	struct spdk_nvme_transport_id trid = {};
1476 
1477 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1478 
1479 	/* Selectively copy the trid. Things like NQN don't matter here - that
1480 	 * mapping is enforced elsewhere.
1481 	 */
1482 	trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
1483 	trid.adrfam = _trid->adrfam;
1484 	snprintf(trid.traddr, sizeof(port->trid.traddr), "%s", _trid->traddr);
1485 	snprintf(trid.trsvcid, sizeof(port->trid.trsvcid), "%s", _trid->trsvcid);
1486 
1487 	pthread_mutex_lock(&rtransport->lock);
1488 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
1489 		if (spdk_nvme_transport_id_compare(&port->trid, &trid) == 0) {
1490 			assert(port->ref > 0);
1491 			port->ref--;
1492 			if (port->ref == 0) {
1493 				TAILQ_REMOVE(&rtransport->ports, port, link);
1494 				rdma_destroy_id(port->id);
1495 				free(port);
1496 			}
1497 			break;
1498 		}
1499 	}
1500 
1501 	pthread_mutex_unlock(&rtransport->lock);
1502 	return 0;
1503 }
1504 
1505 static void
1506 spdk_nvmf_process_cm_event(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
1507 {
1508 	struct spdk_nvmf_rdma_transport *rtransport;
1509 	struct rdma_cm_event		*event;
1510 	int				rc;
1511 
1512 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1513 
1514 	if (rtransport->event_channel == NULL) {
1515 		return;
1516 	}
1517 
1518 	while (1) {
1519 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
1520 		if (rc == 0) {
1521 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
1522 
1523 			switch (event->event) {
1524 			case RDMA_CM_EVENT_ADDR_RESOLVED:
1525 			case RDMA_CM_EVENT_ADDR_ERROR:
1526 			case RDMA_CM_EVENT_ROUTE_RESOLVED:
1527 			case RDMA_CM_EVENT_ROUTE_ERROR:
1528 				/* No action required. The target never attempts to resolve routes. */
1529 				break;
1530 			case RDMA_CM_EVENT_CONNECT_REQUEST:
1531 				rc = nvmf_rdma_connect(transport, event, cb_fn);
1532 				if (rc < 0) {
1533 					SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
1534 					break;
1535 				}
1536 				break;
1537 			case RDMA_CM_EVENT_CONNECT_RESPONSE:
1538 				/* The target never initiates a new connection. So this will not occur. */
1539 				break;
1540 			case RDMA_CM_EVENT_CONNECT_ERROR:
1541 				/* Can this happen? The docs say it can, but not sure what causes it. */
1542 				break;
1543 			case RDMA_CM_EVENT_UNREACHABLE:
1544 			case RDMA_CM_EVENT_REJECTED:
1545 				/* These only occur on the client side. */
1546 				break;
1547 			case RDMA_CM_EVENT_ESTABLISHED:
1548 				/* TODO: Should we be waiting for this event anywhere? */
1549 				break;
1550 			case RDMA_CM_EVENT_DISCONNECTED:
1551 			case RDMA_CM_EVENT_DEVICE_REMOVAL:
1552 				rc = nvmf_rdma_disconnect(event);
1553 				if (rc < 0) {
1554 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
1555 					break;
1556 				}
1557 				continue;
1558 			case RDMA_CM_EVENT_MULTICAST_JOIN:
1559 			case RDMA_CM_EVENT_MULTICAST_ERROR:
1560 				/* Multicast is not used */
1561 				break;
1562 			case RDMA_CM_EVENT_ADDR_CHANGE:
1563 				/* Not utilizing this event */
1564 				break;
1565 			case RDMA_CM_EVENT_TIMEWAIT_EXIT:
1566 				/* For now, do nothing. The target never re-uses queue pairs. */
1567 				break;
1568 			default:
1569 				SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
1570 				break;
1571 			}
1572 
1573 			rdma_ack_cm_event(event);
1574 		} else {
1575 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
1576 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
1577 			}
1578 			break;
1579 		}
1580 	}
1581 }
1582 
1583 static void
1584 spdk_nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
1585 {
1586 	int rc;
1587 	struct ibv_async_event event;
1588 
1589 	rc = ibv_get_async_event(device->context, &event);
1590 
1591 	if (rc) {
1592 		SPDK_ERRLOG("Failed to get async_event (%d): %s\n",
1593 			    errno, spdk_strerror(errno));
1594 		return;
1595 	}
1596 
1597 	SPDK_NOTICELOG("Async event: %s\n",
1598 		       ibv_event_type_str(event.event_type));
1599 	ibv_ack_async_event(&event);
1600 }
1601 
1602 static void
1603 spdk_nvmf_rdma_accept(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
1604 {
1605 	int	nfds, i = 0;
1606 	struct spdk_nvmf_rdma_transport *rtransport;
1607 	struct spdk_nvmf_rdma_device *device, *tmp;
1608 
1609 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1610 	nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
1611 
1612 	if (nfds <= 0) {
1613 		return;
1614 	}
1615 
1616 	/* The first poll descriptor is RDMA CM event */
1617 	if (rtransport->poll_fds[i++].revents & POLLIN) {
1618 		spdk_nvmf_process_cm_event(transport, cb_fn);
1619 		nfds--;
1620 	}
1621 
1622 	if (nfds == 0) {
1623 		return;
1624 	}
1625 
1626 	/* Second and subsequent poll descriptors are IB async events */
1627 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
1628 		if (rtransport->poll_fds[i++].revents & POLLIN) {
1629 			spdk_nvmf_process_ib_event(device);
1630 			nfds--;
1631 		}
1632 	}
1633 	/* check all flagged fd's have been served */
1634 	assert(nfds == 0);
1635 }
1636 
1637 static void
1638 spdk_nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
1639 			struct spdk_nvme_transport_id *trid,
1640 			struct spdk_nvmf_discovery_log_page_entry *entry)
1641 {
1642 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
1643 	entry->adrfam = trid->adrfam;
1644 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_SPECIFIED;
1645 
1646 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
1647 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
1648 
1649 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
1650 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
1651 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
1652 }
1653 
1654 static struct spdk_nvmf_transport_poll_group *
1655 spdk_nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
1656 {
1657 	struct spdk_nvmf_rdma_transport		*rtransport;
1658 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1659 	struct spdk_nvmf_rdma_poller		*poller;
1660 	struct spdk_nvmf_rdma_device		*device;
1661 
1662 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1663 
1664 	rgroup = calloc(1, sizeof(*rgroup));
1665 	if (!rgroup) {
1666 		return NULL;
1667 	}
1668 
1669 	TAILQ_INIT(&rgroup->pollers);
1670 
1671 	pthread_mutex_lock(&rtransport->lock);
1672 	TAILQ_FOREACH(device, &rtransport->devices, link) {
1673 		if (device->map == NULL) {
1674 			/*
1675 			 * The device is not in use (no listeners),
1676 			 * so no protection domain has been constructed.
1677 			 * Skip it.
1678 			 */
1679 			SPDK_NOTICELOG("Skipping unused RDMA device when creating poll group.\n");
1680 			continue;
1681 		}
1682 
1683 		poller = calloc(1, sizeof(*poller));
1684 		if (!poller) {
1685 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
1686 			free(rgroup);
1687 			pthread_mutex_unlock(&rtransport->lock);
1688 			return NULL;
1689 		}
1690 
1691 		poller->device = device;
1692 		poller->group = rgroup;
1693 
1694 		TAILQ_INIT(&poller->qpairs);
1695 
1696 		poller->cq = ibv_create_cq(device->context, NVMF_RDMA_CQ_SIZE, poller, NULL, 0);
1697 		if (!poller->cq) {
1698 			SPDK_ERRLOG("Unable to create completion queue\n");
1699 			free(poller);
1700 			free(rgroup);
1701 			pthread_mutex_unlock(&rtransport->lock);
1702 			return NULL;
1703 		}
1704 
1705 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
1706 	}
1707 
1708 	pthread_mutex_unlock(&rtransport->lock);
1709 	return &rgroup->group;
1710 }
1711 
1712 static void
1713 spdk_nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
1714 {
1715 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1716 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
1717 
1718 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
1719 
1720 	if (!rgroup) {
1721 		return;
1722 	}
1723 
1724 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
1725 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
1726 
1727 		if (poller->cq) {
1728 			ibv_destroy_cq(poller->cq);
1729 		}
1730 
1731 		free(poller);
1732 	}
1733 
1734 	free(rgroup);
1735 }
1736 
1737 static int
1738 spdk_nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
1739 			      struct spdk_nvmf_qpair *qpair)
1740 {
1741 	struct spdk_nvmf_rdma_transport		*rtransport;
1742 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1743 	struct spdk_nvmf_rdma_qpair		*rqpair;
1744 	struct spdk_nvmf_rdma_device		*device;
1745 	struct spdk_nvmf_rdma_poller		*poller;
1746 	int					rc;
1747 
1748 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
1749 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
1750 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1751 
1752 	device = rqpair->port->device;
1753 
1754 	if (device->pd != rqpair->cm_id->pd) {
1755 		SPDK_ERRLOG("Mismatched protection domains\n");
1756 		return -1;
1757 	}
1758 
1759 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
1760 		if (poller->device == device) {
1761 			break;
1762 		}
1763 	}
1764 
1765 	if (!poller) {
1766 		SPDK_ERRLOG("No poller found for device.\n");
1767 		return -1;
1768 	}
1769 
1770 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
1771 	rqpair->poller = poller;
1772 
1773 	rc = spdk_nvmf_rdma_qpair_initialize(qpair);
1774 	if (rc < 0) {
1775 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
1776 		return -1;
1777 	}
1778 
1779 	rqpair->mgmt_channel = spdk_get_io_channel(rtransport);
1780 	if (!rqpair->mgmt_channel) {
1781 		spdk_nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1782 		spdk_nvmf_rdma_qpair_destroy(rqpair);
1783 		return -1;
1784 	}
1785 
1786 	rqpair->ch = spdk_io_channel_get_ctx(rqpair->mgmt_channel);
1787 	assert(rqpair->ch != NULL);
1788 
1789 	rc = spdk_nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
1790 	if (rc) {
1791 		/* Try to reject, but we probably can't */
1792 		spdk_nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1793 		spdk_nvmf_rdma_qpair_destroy(rqpair);
1794 		return -1;
1795 	}
1796 
1797 	return 0;
1798 }
1799 
1800 static int
1801 spdk_nvmf_rdma_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
1802 				 struct spdk_nvmf_qpair *qpair)
1803 {
1804 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1805 	struct spdk_nvmf_rdma_qpair		*rqpair;
1806 	struct spdk_nvmf_rdma_device		*device;
1807 	struct spdk_nvmf_rdma_poller		*poller;
1808 	struct spdk_nvmf_rdma_qpair		*rq, *trq;
1809 
1810 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
1811 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1812 
1813 	device = rqpair->port->device;
1814 
1815 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
1816 		if (poller->device == device) {
1817 			break;
1818 		}
1819 	}
1820 
1821 	if (!poller) {
1822 		SPDK_ERRLOG("No poller found for device.\n");
1823 		return -1;
1824 	}
1825 
1826 	TAILQ_FOREACH_SAFE(rq, &poller->qpairs, link, trq) {
1827 		if (rq == rqpair) {
1828 			TAILQ_REMOVE(&poller->qpairs, rqpair, link);
1829 			break;
1830 		}
1831 	}
1832 
1833 	if (rq == NULL) {
1834 		SPDK_ERRLOG("RDMA qpair cannot be removed from group (not in group).\n");
1835 		return -1;
1836 	}
1837 
1838 	return 0;
1839 }
1840 
1841 static int
1842 spdk_nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
1843 {
1844 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
1845 			struct spdk_nvmf_rdma_transport, transport);
1846 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1847 
1848 	rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
1849 	spdk_nvmf_rdma_request_process(rtransport, rdma_req);
1850 
1851 	return 0;
1852 }
1853 
1854 static void
1855 spdk_nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair)
1856 {
1857 	spdk_nvmf_rdma_qpair_destroy(SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair));
1858 }
1859 
1860 static void
1861 spdk_nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
1862 				     struct spdk_nvmf_rdma_qpair *rqpair)
1863 {
1864 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
1865 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
1866 
1867 	/* We process I/O in the pending_rdma_rw queue at the highest priority. */
1868 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_rw_queue, link, req_tmp) {
1869 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false) {
1870 			break;
1871 		}
1872 	}
1873 
1874 	/* The second highest priority is I/O waiting on memory buffers. */
1875 	TAILQ_FOREACH_SAFE(rdma_req, &rqpair->ch->pending_data_buf_queue, link, req_tmp) {
1876 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false) {
1877 			break;
1878 		}
1879 	}
1880 
1881 	/* The lowest priority is processing newly received commands */
1882 	TAILQ_FOREACH_SAFE(rdma_recv, &rqpair->incoming_queue, link, recv_tmp) {
1883 		rdma_req = TAILQ_FIRST(&rqpair->free_queue);
1884 		if (rdma_req == NULL) {
1885 			/* Need to wait for more SEND completions */
1886 			break;
1887 		}
1888 
1889 		rdma_req->recv = rdma_recv;
1890 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
1891 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false) {
1892 			break;
1893 		}
1894 	}
1895 }
1896 
1897 static struct spdk_nvmf_rdma_request *
1898 get_rdma_req_from_wc(struct ibv_wc *wc)
1899 {
1900 	struct spdk_nvmf_rdma_request *rdma_req;
1901 
1902 	rdma_req = (struct spdk_nvmf_rdma_request *)wc->wr_id;
1903 	assert(rdma_req != NULL);
1904 
1905 #ifdef DEBUG
1906 	struct spdk_nvmf_rdma_qpair *rqpair;
1907 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1908 
1909 	assert(rdma_req - rqpair->reqs >= 0);
1910 	assert(rdma_req - rqpair->reqs < (ptrdiff_t)rqpair->max_queue_depth);
1911 #endif
1912 
1913 	return rdma_req;
1914 }
1915 
1916 static struct spdk_nvmf_rdma_recv *
1917 get_rdma_recv_from_wc(struct ibv_wc *wc)
1918 {
1919 	struct spdk_nvmf_rdma_recv *rdma_recv;
1920 
1921 	assert(wc->byte_len >= sizeof(struct spdk_nvmf_capsule_cmd));
1922 
1923 	rdma_recv = (struct spdk_nvmf_rdma_recv *)wc->wr_id;
1924 	assert(rdma_recv != NULL);
1925 
1926 #ifdef DEBUG
1927 	struct spdk_nvmf_rdma_qpair *rqpair = rdma_recv->qpair;
1928 
1929 	assert(rdma_recv - rqpair->recvs >= 0);
1930 	assert(rdma_recv - rqpair->recvs < (ptrdiff_t)rqpair->max_queue_depth);
1931 #endif
1932 
1933 	return rdma_recv;
1934 }
1935 
1936 static int
1937 spdk_nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
1938 			   struct spdk_nvmf_rdma_poller *rpoller)
1939 {
1940 	struct ibv_wc wc[32];
1941 	struct spdk_nvmf_rdma_request	*rdma_req;
1942 	struct spdk_nvmf_rdma_recv	*rdma_recv;
1943 	struct spdk_nvmf_rdma_qpair	*rqpair;
1944 	int reaped, i;
1945 	int count = 0;
1946 	bool error = false;
1947 
1948 	/* Poll for completing operations. */
1949 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
1950 	if (reaped < 0) {
1951 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
1952 			    errno, spdk_strerror(errno));
1953 		return -1;
1954 	}
1955 
1956 	for (i = 0; i < reaped; i++) {
1957 		if (wc[i].status) {
1958 			SPDK_ERRLOG("CQ error on CQ %p, Request 0x%lu (%d): %s\n",
1959 				    rpoller->cq, wc[i].wr_id, wc[i].status, ibv_wc_status_str(wc[i].status));
1960 			error = true;
1961 			continue;
1962 		}
1963 
1964 		switch (wc[i].opcode) {
1965 		case IBV_WC_SEND:
1966 			rdma_req = get_rdma_req_from_wc(&wc[i]);
1967 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1968 
1969 			assert(rdma_req->state == RDMA_REQUEST_STATE_COMPLETING);
1970 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
1971 
1972 			spdk_nvmf_rdma_request_process(rtransport, rdma_req);
1973 
1974 			count++;
1975 
1976 			/* Try to process other queued requests */
1977 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair);
1978 			break;
1979 
1980 		case IBV_WC_RDMA_WRITE:
1981 			rdma_req = get_rdma_req_from_wc(&wc[i]);
1982 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1983 
1984 			rqpair->cur_rdma_rw_depth--;
1985 
1986 			/* Try to process other queued requests */
1987 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair);
1988 			break;
1989 
1990 		case IBV_WC_RDMA_READ:
1991 			rdma_req = get_rdma_req_from_wc(&wc[i]);
1992 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1993 
1994 			assert(rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
1995 			rqpair->cur_rdma_rw_depth--;
1996 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
1997 
1998 			spdk_nvmf_rdma_request_process(rtransport, rdma_req);
1999 
2000 			/* Try to process other queued requests */
2001 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair);
2002 			break;
2003 
2004 		case IBV_WC_RECV:
2005 			rdma_recv = get_rdma_recv_from_wc(&wc[i]);
2006 			rqpair = rdma_recv->qpair;
2007 
2008 			TAILQ_INSERT_TAIL(&rqpair->incoming_queue, rdma_recv, link);
2009 
2010 			/* Try to process other queued requests */
2011 			spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair);
2012 			break;
2013 
2014 		default:
2015 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
2016 			continue;
2017 		}
2018 	}
2019 
2020 	if (error == true) {
2021 		return -1;
2022 	}
2023 
2024 	return count;
2025 }
2026 
2027 static int
2028 spdk_nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
2029 {
2030 	struct spdk_nvmf_rdma_transport *rtransport;
2031 	struct spdk_nvmf_rdma_poll_group *rgroup;
2032 	struct spdk_nvmf_rdma_poller	*rpoller;
2033 	int				count, rc;
2034 
2035 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
2036 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
2037 
2038 	count = 0;
2039 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
2040 		rc = spdk_nvmf_rdma_poller_poll(rtransport, rpoller);
2041 		if (rc < 0) {
2042 			return rc;
2043 		}
2044 		count += rc;
2045 	}
2046 
2047 	return count;
2048 }
2049 
2050 static bool
2051 spdk_nvmf_rdma_qpair_is_idle(struct spdk_nvmf_qpair *qpair)
2052 {
2053 	struct spdk_nvmf_rdma_qpair *rqpair;
2054 
2055 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2056 
2057 	if (rqpair->cur_queue_depth == 0 && rqpair->cur_rdma_rw_depth == 0) {
2058 		return true;
2059 	}
2060 	return false;
2061 }
2062 
2063 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
2064 	.type = SPDK_NVME_TRANSPORT_RDMA,
2065 	.create = spdk_nvmf_rdma_create,
2066 	.destroy = spdk_nvmf_rdma_destroy,
2067 
2068 	.listen = spdk_nvmf_rdma_listen,
2069 	.stop_listen = spdk_nvmf_rdma_stop_listen,
2070 	.accept = spdk_nvmf_rdma_accept,
2071 
2072 	.listener_discover = spdk_nvmf_rdma_discover,
2073 
2074 	.poll_group_create = spdk_nvmf_rdma_poll_group_create,
2075 	.poll_group_destroy = spdk_nvmf_rdma_poll_group_destroy,
2076 	.poll_group_add = spdk_nvmf_rdma_poll_group_add,
2077 	.poll_group_remove = spdk_nvmf_rdma_poll_group_remove,
2078 	.poll_group_poll = spdk_nvmf_rdma_poll_group_poll,
2079 
2080 	.req_complete = spdk_nvmf_rdma_request_complete,
2081 
2082 	.qpair_fini = spdk_nvmf_rdma_close_qpair,
2083 	.qpair_is_idle = spdk_nvmf_rdma_qpair_is_idle,
2084 
2085 };
2086 
2087 SPDK_LOG_REGISTER_COMPONENT("rdma", SPDK_LOG_RDMA)
2088