xref: /spdk/lib/nvmf/rdma.c (revision 7961de43413e7f818f7499bf8518909beb59c82f)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2019 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/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/assert.h"
52 #include "spdk_internal/log.h"
53 
54 struct spdk_nvme_rdma_hooks g_nvmf_hooks = {};
55 
56 /*
57  RDMA Connection Resource Defaults
58  */
59 #define NVMF_DEFAULT_TX_SGE		SPDK_NVMF_MAX_SGL_ENTRIES
60 #define NVMF_DEFAULT_RSP_SGE		1
61 #define NVMF_DEFAULT_RX_SGE		2
62 
63 /* The RDMA completion queue size */
64 #define DEFAULT_NVMF_RDMA_CQ_SIZE	4096
65 #define MAX_WR_PER_QP(queue_depth)	(queue_depth * 3 + 2)
66 
67 /* Timeout for destroying defunct rqpairs */
68 #define NVMF_RDMA_QPAIR_DESTROY_TIMEOUT_US	4000000
69 
70 static int g_spdk_nvmf_ibv_query_mask =
71 	IBV_QP_STATE |
72 	IBV_QP_PKEY_INDEX |
73 	IBV_QP_PORT |
74 	IBV_QP_ACCESS_FLAGS |
75 	IBV_QP_AV |
76 	IBV_QP_PATH_MTU |
77 	IBV_QP_DEST_QPN |
78 	IBV_QP_RQ_PSN |
79 	IBV_QP_MAX_DEST_RD_ATOMIC |
80 	IBV_QP_MIN_RNR_TIMER |
81 	IBV_QP_SQ_PSN |
82 	IBV_QP_TIMEOUT |
83 	IBV_QP_RETRY_CNT |
84 	IBV_QP_RNR_RETRY |
85 	IBV_QP_MAX_QP_RD_ATOMIC;
86 
87 enum spdk_nvmf_rdma_request_state {
88 	/* The request is not currently in use */
89 	RDMA_REQUEST_STATE_FREE = 0,
90 
91 	/* Initial state when request first received */
92 	RDMA_REQUEST_STATE_NEW,
93 
94 	/* The request is queued until a data buffer is available. */
95 	RDMA_REQUEST_STATE_NEED_BUFFER,
96 
97 	/* The request is waiting on RDMA queue depth availability
98 	 * to transfer data from the host to the controller.
99 	 */
100 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
101 
102 	/* The request is currently transferring data from the host to the controller. */
103 	RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
104 
105 	/* The request is ready to execute at the block device */
106 	RDMA_REQUEST_STATE_READY_TO_EXECUTE,
107 
108 	/* The request is currently executing at the block device */
109 	RDMA_REQUEST_STATE_EXECUTING,
110 
111 	/* The request finished executing at the block device */
112 	RDMA_REQUEST_STATE_EXECUTED,
113 
114 	/* The request is waiting on RDMA queue depth availability
115 	 * to transfer data from the controller to the host.
116 	 */
117 	RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
118 
119 	/* The request is ready to send a completion */
120 	RDMA_REQUEST_STATE_READY_TO_COMPLETE,
121 
122 	/* The request is currently transferring data from the controller to the host. */
123 	RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
124 
125 	/* The request currently has an outstanding completion without an
126 	 * associated data transfer.
127 	 */
128 	RDMA_REQUEST_STATE_COMPLETING,
129 
130 	/* The request completed and can be marked free. */
131 	RDMA_REQUEST_STATE_COMPLETED,
132 
133 	/* Terminator */
134 	RDMA_REQUEST_NUM_STATES,
135 };
136 
137 #define OBJECT_NVMF_RDMA_IO				0x40
138 
139 #define TRACE_GROUP_NVMF_RDMA				0x4
140 #define TRACE_RDMA_REQUEST_STATE_NEW					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x0)
141 #define TRACE_RDMA_REQUEST_STATE_NEED_BUFFER				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x1)
142 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x2)
143 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x3)
144 #define TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x4)
145 #define TRACE_RDMA_REQUEST_STATE_EXECUTING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x5)
146 #define TRACE_RDMA_REQUEST_STATE_EXECUTED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x6)
147 #define TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING		SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x7)
148 #define TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x8)
149 #define TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST	SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x9)
150 #define TRACE_RDMA_REQUEST_STATE_COMPLETING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xA)
151 #define TRACE_RDMA_REQUEST_STATE_COMPLETED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xB)
152 #define TRACE_RDMA_QP_CREATE						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xC)
153 #define TRACE_RDMA_IBV_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xD)
154 #define TRACE_RDMA_CM_ASYNC_EVENT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xE)
155 #define TRACE_RDMA_QP_STATE_CHANGE					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0xF)
156 #define TRACE_RDMA_QP_DISCONNECT					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x10)
157 #define TRACE_RDMA_QP_DESTROY						SPDK_TPOINT_ID(TRACE_GROUP_NVMF_RDMA, 0x11)
158 
159 SPDK_TRACE_REGISTER_FN(nvmf_trace, "nvmf_rdma", TRACE_GROUP_NVMF_RDMA)
160 {
161 	spdk_trace_register_object(OBJECT_NVMF_RDMA_IO, 'r');
162 	spdk_trace_register_description("RDMA_REQ_NEW", TRACE_RDMA_REQUEST_STATE_NEW,
163 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 1, 1, "cmid:   ");
164 	spdk_trace_register_description("RDMA_REQ_NEED_BUFFER", TRACE_RDMA_REQUEST_STATE_NEED_BUFFER,
165 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
166 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_C2H",
167 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING,
168 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
169 	spdk_trace_register_description("RDMA_REQ_TX_PENDING_H2C",
170 					TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING,
171 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
172 	spdk_trace_register_description("RDMA_REQ_TX_H2C",
173 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
174 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
175 	spdk_trace_register_description("RDMA_REQ_RDY_TO_EXECUTE",
176 					TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE,
177 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
178 	spdk_trace_register_description("RDMA_REQ_EXECUTING",
179 					TRACE_RDMA_REQUEST_STATE_EXECUTING,
180 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
181 	spdk_trace_register_description("RDMA_REQ_EXECUTED",
182 					TRACE_RDMA_REQUEST_STATE_EXECUTED,
183 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
184 	spdk_trace_register_description("RDMA_REQ_RDY_TO_COMPL",
185 					TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE,
186 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
187 	spdk_trace_register_description("RDMA_REQ_COMPLETING_C2H",
188 					TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
189 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
190 	spdk_trace_register_description("RDMA_REQ_COMPLETING",
191 					TRACE_RDMA_REQUEST_STATE_COMPLETING,
192 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
193 	spdk_trace_register_description("RDMA_REQ_COMPLETED",
194 					TRACE_RDMA_REQUEST_STATE_COMPLETED,
195 					OWNER_NONE, OBJECT_NVMF_RDMA_IO, 0, 1, "cmid:   ");
196 
197 	spdk_trace_register_description("RDMA_QP_CREATE", TRACE_RDMA_QP_CREATE,
198 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
199 	spdk_trace_register_description("RDMA_IBV_ASYNC_EVENT", TRACE_RDMA_IBV_ASYNC_EVENT,
200 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
201 	spdk_trace_register_description("RDMA_CM_ASYNC_EVENT", TRACE_RDMA_CM_ASYNC_EVENT,
202 					OWNER_NONE, OBJECT_NONE, 0, 0, "type:   ");
203 	spdk_trace_register_description("RDMA_QP_STATE_CHANGE", TRACE_RDMA_QP_STATE_CHANGE,
204 					OWNER_NONE, OBJECT_NONE, 0, 1, "state:  ");
205 	spdk_trace_register_description("RDMA_QP_DISCONNECT", TRACE_RDMA_QP_DISCONNECT,
206 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
207 	spdk_trace_register_description("RDMA_QP_DESTROY", TRACE_RDMA_QP_DESTROY,
208 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
209 }
210 
211 enum spdk_nvmf_rdma_wr_type {
212 	RDMA_WR_TYPE_RECV,
213 	RDMA_WR_TYPE_SEND,
214 	RDMA_WR_TYPE_DATA,
215 };
216 
217 struct spdk_nvmf_rdma_wr {
218 	enum spdk_nvmf_rdma_wr_type	type;
219 };
220 
221 /* This structure holds commands as they are received off the wire.
222  * It must be dynamically paired with a full request object
223  * (spdk_nvmf_rdma_request) to service a request. It is separate
224  * from the request because RDMA does not appear to order
225  * completions, so occasionally we'll get a new incoming
226  * command when there aren't any free request objects.
227  */
228 struct spdk_nvmf_rdma_recv {
229 	struct ibv_recv_wr			wr;
230 	struct ibv_sge				sgl[NVMF_DEFAULT_RX_SGE];
231 
232 	struct spdk_nvmf_rdma_qpair		*qpair;
233 
234 	/* In-capsule data buffer */
235 	uint8_t					*buf;
236 
237 	struct spdk_nvmf_rdma_wr		rdma_wr;
238 	uint64_t				receive_tsc;
239 
240 	STAILQ_ENTRY(spdk_nvmf_rdma_recv)	link;
241 };
242 
243 struct spdk_nvmf_rdma_request_data {
244 	struct spdk_nvmf_rdma_wr	rdma_wr;
245 	struct ibv_send_wr		wr;
246 	struct ibv_sge			sgl[SPDK_NVMF_MAX_SGL_ENTRIES];
247 };
248 
249 struct spdk_nvmf_rdma_request {
250 	struct spdk_nvmf_request		req;
251 
252 	enum spdk_nvmf_rdma_request_state	state;
253 
254 	struct spdk_nvmf_rdma_recv		*recv;
255 
256 	struct {
257 		struct spdk_nvmf_rdma_wr	rdma_wr;
258 		struct	ibv_send_wr		wr;
259 		struct	ibv_sge			sgl[NVMF_DEFAULT_RSP_SGE];
260 	} rsp;
261 
262 	struct spdk_nvmf_rdma_request_data	data;
263 
264 	uint32_t				iovpos;
265 
266 	uint32_t				num_outstanding_data_wr;
267 	uint64_t				receive_tsc;
268 
269 	STAILQ_ENTRY(spdk_nvmf_rdma_request)	state_link;
270 };
271 
272 enum spdk_nvmf_rdma_qpair_disconnect_flags {
273 	RDMA_QP_DISCONNECTING		= 1,
274 	RDMA_QP_RECV_DRAINED		= 1 << 1,
275 	RDMA_QP_SEND_DRAINED		= 1 << 2
276 };
277 
278 struct spdk_nvmf_rdma_resource_opts {
279 	struct spdk_nvmf_rdma_qpair	*qpair;
280 	/* qp points either to an ibv_qp object or an ibv_srq object depending on the value of shared. */
281 	void				*qp;
282 	struct ibv_pd			*pd;
283 	uint32_t			max_queue_depth;
284 	uint32_t			in_capsule_data_size;
285 	bool				shared;
286 };
287 
288 struct spdk_nvmf_send_wr_list {
289 	struct ibv_send_wr	*first;
290 	struct ibv_send_wr	*last;
291 };
292 
293 struct spdk_nvmf_recv_wr_list {
294 	struct ibv_recv_wr	*first;
295 	struct ibv_recv_wr	*last;
296 };
297 
298 struct spdk_nvmf_rdma_resources {
299 	/* Array of size "max_queue_depth" containing RDMA requests. */
300 	struct spdk_nvmf_rdma_request		*reqs;
301 
302 	/* Array of size "max_queue_depth" containing RDMA recvs. */
303 	struct spdk_nvmf_rdma_recv		*recvs;
304 
305 	/* Array of size "max_queue_depth" containing 64 byte capsules
306 	 * used for receive.
307 	 */
308 	union nvmf_h2c_msg			*cmds;
309 	struct ibv_mr				*cmds_mr;
310 
311 	/* Array of size "max_queue_depth" containing 16 byte completions
312 	 * to be sent back to the user.
313 	 */
314 	union nvmf_c2h_msg			*cpls;
315 	struct ibv_mr				*cpls_mr;
316 
317 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
318 	 * buffers to be used for in capsule data.
319 	 */
320 	void					*bufs;
321 	struct ibv_mr				*bufs_mr;
322 
323 	/* The list of pending recvs to transfer */
324 	struct spdk_nvmf_recv_wr_list		recvs_to_post;
325 
326 	/* Receives that are waiting for a request object */
327 	STAILQ_HEAD(, spdk_nvmf_rdma_recv)	incoming_queue;
328 
329 	/* Queue to track free requests */
330 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	free_queue;
331 };
332 
333 typedef void (*spdk_nvmf_rdma_qpair_ibv_event)(struct spdk_nvmf_rdma_qpair *rqpair);
334 
335 struct spdk_nvmf_rdma_ibv_event_ctx {
336 	struct spdk_nvmf_rdma_qpair			*rqpair;
337 	spdk_nvmf_rdma_qpair_ibv_event			cb_fn;
338 	/* Link to other ibv events associated with this qpair */
339 	STAILQ_ENTRY(spdk_nvmf_rdma_ibv_event_ctx)	link;
340 };
341 
342 struct spdk_nvmf_rdma_qpair {
343 	struct spdk_nvmf_qpair			qpair;
344 
345 	struct spdk_nvmf_rdma_port		*port;
346 	struct spdk_nvmf_rdma_poller		*poller;
347 
348 	struct rdma_cm_id			*cm_id;
349 	struct ibv_srq				*srq;
350 	struct rdma_cm_id			*listen_id;
351 
352 	/* The maximum number of I/O outstanding on this connection at one time */
353 	uint16_t				max_queue_depth;
354 
355 	/* The maximum number of active RDMA READ and ATOMIC operations at one time */
356 	uint16_t				max_read_depth;
357 
358 	/* The maximum number of RDMA SEND operations at one time */
359 	uint32_t				max_send_depth;
360 
361 	/* The current number of outstanding WRs from this qpair's
362 	 * recv queue. Should not exceed device->attr.max_queue_depth.
363 	 */
364 	uint16_t				current_recv_depth;
365 
366 	/* The current number of active RDMA READ operations */
367 	uint16_t				current_read_depth;
368 
369 	/* The current number of posted WRs from this qpair's
370 	 * send queue. Should not exceed max_send_depth.
371 	 */
372 	uint32_t				current_send_depth;
373 
374 	/* The maximum number of SGEs per WR on the send queue */
375 	uint32_t				max_send_sge;
376 
377 	/* The maximum number of SGEs per WR on the recv queue */
378 	uint32_t				max_recv_sge;
379 
380 	/* The list of pending send requests for a transfer */
381 	struct spdk_nvmf_send_wr_list		sends_to_post;
382 
383 	struct spdk_nvmf_rdma_resources		*resources;
384 
385 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_read_queue;
386 
387 	STAILQ_HEAD(, spdk_nvmf_rdma_request)	pending_rdma_write_queue;
388 
389 	/* Number of requests not in the free state */
390 	uint32_t				qd;
391 
392 	TAILQ_ENTRY(spdk_nvmf_rdma_qpair)	link;
393 
394 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	recv_link;
395 
396 	STAILQ_ENTRY(spdk_nvmf_rdma_qpair)	send_link;
397 
398 	/* IBV queue pair attributes: they are used to manage
399 	 * qp state and recover from errors.
400 	 */
401 	enum ibv_qp_state			ibv_state;
402 
403 	uint32_t				disconnect_flags;
404 
405 	/* Poller registered in case the qpair doesn't properly
406 	 * complete the qpair destruct process and becomes defunct.
407 	 */
408 
409 	struct spdk_poller			*destruct_poller;
410 
411 	/* List of ibv async events */
412 	STAILQ_HEAD(, spdk_nvmf_rdma_ibv_event_ctx)	ibv_events;
413 
414 	/* There are several ways a disconnect can start on a qpair
415 	 * and they are not all mutually exclusive. It is important
416 	 * that we only initialize one of these paths.
417 	 */
418 	bool					disconnect_started;
419 	/* Lets us know that we have received the last_wqe event. */
420 	bool					last_wqe_reached;
421 };
422 
423 struct spdk_nvmf_rdma_poller_stat {
424 	uint64_t				completions;
425 	uint64_t				polls;
426 	uint64_t				requests;
427 	uint64_t				request_latency;
428 	uint64_t				pending_free_request;
429 	uint64_t				pending_rdma_read;
430 	uint64_t				pending_rdma_write;
431 };
432 
433 struct spdk_nvmf_rdma_poller {
434 	struct spdk_nvmf_rdma_device		*device;
435 	struct spdk_nvmf_rdma_poll_group	*group;
436 
437 	int					num_cqe;
438 	int					required_num_wr;
439 	struct ibv_cq				*cq;
440 
441 	/* The maximum number of I/O outstanding on the shared receive queue at one time */
442 	uint16_t				max_srq_depth;
443 
444 	/* Shared receive queue */
445 	struct ibv_srq				*srq;
446 
447 	struct spdk_nvmf_rdma_resources		*resources;
448 	struct spdk_nvmf_rdma_poller_stat	stat;
449 
450 	TAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs;
451 
452 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_recv;
453 
454 	STAILQ_HEAD(, spdk_nvmf_rdma_qpair)	qpairs_pending_send;
455 
456 	TAILQ_ENTRY(spdk_nvmf_rdma_poller)	link;
457 };
458 
459 struct spdk_nvmf_rdma_poll_group_stat {
460 	uint64_t				pending_data_buffer;
461 };
462 
463 struct spdk_nvmf_rdma_poll_group {
464 	struct spdk_nvmf_transport_poll_group		group;
465 	struct spdk_nvmf_rdma_poll_group_stat		stat;
466 	TAILQ_HEAD(, spdk_nvmf_rdma_poller)		pollers;
467 	TAILQ_ENTRY(spdk_nvmf_rdma_poll_group)		link;
468 	/*
469 	 * buffers which are split across multiple RDMA
470 	 * memory regions cannot be used by this transport.
471 	 */
472 	STAILQ_HEAD(, spdk_nvmf_transport_pg_cache_buf)	retired_bufs;
473 };
474 
475 struct spdk_nvmf_rdma_conn_sched {
476 	struct spdk_nvmf_rdma_poll_group *next_admin_pg;
477 	struct spdk_nvmf_rdma_poll_group *next_io_pg;
478 };
479 
480 /* Assuming rdma_cm uses just one protection domain per ibv_context. */
481 struct spdk_nvmf_rdma_device {
482 	struct ibv_device_attr			attr;
483 	struct ibv_context			*context;
484 
485 	struct spdk_mem_map			*map;
486 	struct ibv_pd				*pd;
487 
488 	int					num_srq;
489 
490 	TAILQ_ENTRY(spdk_nvmf_rdma_device)	link;
491 };
492 
493 struct spdk_nvmf_rdma_port {
494 	struct spdk_nvme_transport_id		trid;
495 	struct rdma_cm_id			*id;
496 	struct spdk_nvmf_rdma_device		*device;
497 	uint32_t				ref;
498 	TAILQ_ENTRY(spdk_nvmf_rdma_port)	link;
499 };
500 
501 struct spdk_nvmf_rdma_transport {
502 	struct spdk_nvmf_transport	transport;
503 
504 	struct spdk_nvmf_rdma_conn_sched conn_sched;
505 
506 	struct rdma_event_channel	*event_channel;
507 
508 	struct spdk_mempool		*data_wr_pool;
509 
510 	pthread_mutex_t			lock;
511 
512 	/* fields used to poll RDMA/IB events */
513 	nfds_t			npoll_fds;
514 	struct pollfd		*poll_fds;
515 
516 	TAILQ_HEAD(, spdk_nvmf_rdma_device)	devices;
517 	TAILQ_HEAD(, spdk_nvmf_rdma_port)	ports;
518 	TAILQ_HEAD(, spdk_nvmf_rdma_poll_group)	poll_groups;
519 };
520 
521 static inline void
522 spdk_nvmf_rdma_start_disconnect(struct spdk_nvmf_rdma_qpair *rqpair);
523 
524 static inline int
525 spdk_nvmf_rdma_check_ibv_state(enum ibv_qp_state state)
526 {
527 	switch (state) {
528 	case IBV_QPS_RESET:
529 	case IBV_QPS_INIT:
530 	case IBV_QPS_RTR:
531 	case IBV_QPS_RTS:
532 	case IBV_QPS_SQD:
533 	case IBV_QPS_SQE:
534 	case IBV_QPS_ERR:
535 		return 0;
536 	default:
537 		return -1;
538 	}
539 }
540 
541 static inline enum spdk_nvme_media_error_status_code
542 spdk_nvmf_rdma_dif_error_to_compl_status(uint8_t err_type) {
543 	enum spdk_nvme_media_error_status_code result;
544 	switch (err_type)
545 	{
546 	case SPDK_DIF_REFTAG_ERROR:
547 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
548 		break;
549 	case SPDK_DIF_APPTAG_ERROR:
550 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
551 		break;
552 	case SPDK_DIF_GUARD_ERROR:
553 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
554 		break;
555 	default:
556 		SPDK_UNREACHABLE();
557 	}
558 
559 	return result;
560 }
561 
562 static enum ibv_qp_state
563 spdk_nvmf_rdma_update_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair) {
564 	enum ibv_qp_state old_state, new_state;
565 	struct ibv_qp_attr qp_attr;
566 	struct ibv_qp_init_attr init_attr;
567 	int rc;
568 
569 	old_state = rqpair->ibv_state;
570 	rc = ibv_query_qp(rqpair->cm_id->qp, &qp_attr,
571 			  g_spdk_nvmf_ibv_query_mask, &init_attr);
572 
573 	if (rc)
574 	{
575 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
576 		return IBV_QPS_ERR + 1;
577 	}
578 
579 	new_state = qp_attr.qp_state;
580 	rqpair->ibv_state = new_state;
581 	qp_attr.ah_attr.port_num = qp_attr.port_num;
582 
583 	rc = spdk_nvmf_rdma_check_ibv_state(new_state);
584 	if (rc)
585 	{
586 		SPDK_ERRLOG("QP#%d: bad state updated: %u, maybe hardware issue\n", rqpair->qpair.qid, new_state);
587 		/*
588 		 * IBV_QPS_UNKNOWN undefined if lib version smaller than libibverbs-1.1.8
589 		 * IBV_QPS_UNKNOWN is the enum element after IBV_QPS_ERR
590 		 */
591 		return IBV_QPS_ERR + 1;
592 	}
593 
594 	if (old_state != new_state)
595 	{
596 		spdk_trace_record(TRACE_RDMA_QP_STATE_CHANGE, 0, 0,
597 				  (uintptr_t)rqpair->cm_id, new_state);
598 	}
599 	return new_state;
600 }
601 
602 static const char *str_ibv_qp_state[] = {
603 	"IBV_QPS_RESET",
604 	"IBV_QPS_INIT",
605 	"IBV_QPS_RTR",
606 	"IBV_QPS_RTS",
607 	"IBV_QPS_SQD",
608 	"IBV_QPS_SQE",
609 	"IBV_QPS_ERR",
610 	"IBV_QPS_UNKNOWN"
611 };
612 
613 static int
614 spdk_nvmf_rdma_set_ibv_state(struct spdk_nvmf_rdma_qpair *rqpair,
615 			     enum ibv_qp_state new_state)
616 {
617 	struct ibv_qp_attr qp_attr;
618 	struct ibv_qp_init_attr init_attr;
619 	int rc;
620 	enum ibv_qp_state state;
621 	static int attr_mask_rc[] = {
622 		[IBV_QPS_RESET] = IBV_QP_STATE,
623 		[IBV_QPS_INIT] = (IBV_QP_STATE |
624 				  IBV_QP_PKEY_INDEX |
625 				  IBV_QP_PORT |
626 				  IBV_QP_ACCESS_FLAGS),
627 		[IBV_QPS_RTR] = (IBV_QP_STATE |
628 				 IBV_QP_AV |
629 				 IBV_QP_PATH_MTU |
630 				 IBV_QP_DEST_QPN |
631 				 IBV_QP_RQ_PSN |
632 				 IBV_QP_MAX_DEST_RD_ATOMIC |
633 				 IBV_QP_MIN_RNR_TIMER),
634 		[IBV_QPS_RTS] = (IBV_QP_STATE |
635 				 IBV_QP_SQ_PSN |
636 				 IBV_QP_TIMEOUT |
637 				 IBV_QP_RETRY_CNT |
638 				 IBV_QP_RNR_RETRY |
639 				 IBV_QP_MAX_QP_RD_ATOMIC),
640 		[IBV_QPS_SQD] = IBV_QP_STATE,
641 		[IBV_QPS_SQE] = IBV_QP_STATE,
642 		[IBV_QPS_ERR] = IBV_QP_STATE,
643 	};
644 
645 	rc = spdk_nvmf_rdma_check_ibv_state(new_state);
646 	if (rc) {
647 		SPDK_ERRLOG("QP#%d: bad state requested: %u\n",
648 			    rqpair->qpair.qid, new_state);
649 		return rc;
650 	}
651 
652 	rc = ibv_query_qp(rqpair->cm_id->qp, &qp_attr,
653 			  g_spdk_nvmf_ibv_query_mask, &init_attr);
654 
655 	if (rc) {
656 		SPDK_ERRLOG("Failed to get updated RDMA queue pair state!\n");
657 		assert(false);
658 	}
659 
660 	qp_attr.cur_qp_state = rqpair->ibv_state;
661 	qp_attr.qp_state = new_state;
662 
663 	rc = ibv_modify_qp(rqpair->cm_id->qp, &qp_attr,
664 			   attr_mask_rc[new_state]);
665 
666 	if (rc) {
667 		SPDK_ERRLOG("QP#%d: failed to set state to: %s, %d (%s)\n",
668 			    rqpair->qpair.qid, str_ibv_qp_state[new_state], errno, strerror(errno));
669 		return rc;
670 	}
671 
672 	state = spdk_nvmf_rdma_update_ibv_state(rqpair);
673 
674 	if (state != new_state) {
675 		SPDK_ERRLOG("QP#%d: expected state: %s, actual state: %s\n",
676 			    rqpair->qpair.qid, str_ibv_qp_state[new_state],
677 			    str_ibv_qp_state[state]);
678 		return -1;
679 	}
680 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "IBV QP#%u changed to: %s\n", rqpair->qpair.qid,
681 		      str_ibv_qp_state[state]);
682 	return 0;
683 }
684 
685 static void
686 nvmf_rdma_request_free_data(struct spdk_nvmf_rdma_request *rdma_req,
687 			    struct spdk_nvmf_rdma_transport *rtransport)
688 {
689 	struct spdk_nvmf_rdma_request_data	*data_wr;
690 	struct ibv_send_wr			*next_send_wr;
691 	uint64_t				req_wrid;
692 
693 	rdma_req->num_outstanding_data_wr = 0;
694 	data_wr = &rdma_req->data;
695 	req_wrid = data_wr->wr.wr_id;
696 	while (data_wr && data_wr->wr.wr_id == req_wrid) {
697 		memset(data_wr->sgl, 0, sizeof(data_wr->wr.sg_list[0]) * data_wr->wr.num_sge);
698 		data_wr->wr.num_sge = 0;
699 		next_send_wr = data_wr->wr.next;
700 		if (data_wr != &rdma_req->data) {
701 			spdk_mempool_put(rtransport->data_wr_pool, data_wr);
702 		}
703 		data_wr = (!next_send_wr || next_send_wr == &rdma_req->rsp.wr) ? NULL :
704 			  SPDK_CONTAINEROF(next_send_wr, struct spdk_nvmf_rdma_request_data, wr);
705 	}
706 }
707 
708 static void
709 nvmf_rdma_dump_request(struct spdk_nvmf_rdma_request *req)
710 {
711 	SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", req->req.data_from_pool);
712 	if (req->req.cmd) {
713 		SPDK_ERRLOG("\t\tRequest opcode: %d\n", req->req.cmd->nvmf_cmd.opcode);
714 	}
715 	if (req->recv) {
716 		SPDK_ERRLOG("\t\tRequest recv wr_id%lu\n", req->recv->wr.wr_id);
717 	}
718 }
719 
720 static void
721 nvmf_rdma_dump_qpair_contents(struct spdk_nvmf_rdma_qpair *rqpair)
722 {
723 	int i;
724 
725 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", rqpair->qpair.qid);
726 	for (i = 0; i < rqpair->max_queue_depth; i++) {
727 		if (rqpair->resources->reqs[i].state != RDMA_REQUEST_STATE_FREE) {
728 			nvmf_rdma_dump_request(&rqpair->resources->reqs[i]);
729 		}
730 	}
731 }
732 
733 static void
734 nvmf_rdma_resources_destroy(struct spdk_nvmf_rdma_resources *resources)
735 {
736 	if (resources->cmds_mr) {
737 		ibv_dereg_mr(resources->cmds_mr);
738 	}
739 
740 	if (resources->cpls_mr) {
741 		ibv_dereg_mr(resources->cpls_mr);
742 	}
743 
744 	if (resources->bufs_mr) {
745 		ibv_dereg_mr(resources->bufs_mr);
746 	}
747 
748 	spdk_free(resources->cmds);
749 	spdk_free(resources->cpls);
750 	spdk_free(resources->bufs);
751 	free(resources->reqs);
752 	free(resources->recvs);
753 	free(resources);
754 }
755 
756 
757 static struct spdk_nvmf_rdma_resources *
758 nvmf_rdma_resources_create(struct spdk_nvmf_rdma_resource_opts *opts)
759 {
760 	struct spdk_nvmf_rdma_resources	*resources;
761 	struct spdk_nvmf_rdma_request	*rdma_req;
762 	struct spdk_nvmf_rdma_recv	*rdma_recv;
763 	struct ibv_qp			*qp;
764 	struct ibv_srq			*srq;
765 	uint32_t			i;
766 	int				rc;
767 
768 	resources = calloc(1, sizeof(struct spdk_nvmf_rdma_resources));
769 	if (!resources) {
770 		SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
771 		return NULL;
772 	}
773 
774 	resources->reqs = calloc(opts->max_queue_depth, sizeof(*resources->reqs));
775 	resources->recvs = calloc(opts->max_queue_depth, sizeof(*resources->recvs));
776 	resources->cmds = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cmds),
777 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
778 	resources->cpls = spdk_zmalloc(opts->max_queue_depth * sizeof(*resources->cpls),
779 				       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
780 
781 	if (opts->in_capsule_data_size > 0) {
782 		resources->bufs = spdk_zmalloc(opts->max_queue_depth * opts->in_capsule_data_size,
783 					       0x1000, NULL, SPDK_ENV_LCORE_ID_ANY,
784 					       SPDK_MALLOC_DMA);
785 	}
786 
787 	if (!resources->reqs || !resources->recvs || !resources->cmds ||
788 	    !resources->cpls || (opts->in_capsule_data_size && !resources->bufs)) {
789 		SPDK_ERRLOG("Unable to allocate sufficient memory for RDMA queue.\n");
790 		goto cleanup;
791 	}
792 
793 	resources->cmds_mr = ibv_reg_mr(opts->pd, resources->cmds,
794 					opts->max_queue_depth * sizeof(*resources->cmds),
795 					IBV_ACCESS_LOCAL_WRITE);
796 	resources->cpls_mr = ibv_reg_mr(opts->pd, resources->cpls,
797 					opts->max_queue_depth * sizeof(*resources->cpls),
798 					0);
799 
800 	if (opts->in_capsule_data_size) {
801 		resources->bufs_mr = ibv_reg_mr(opts->pd, resources->bufs,
802 						opts->max_queue_depth *
803 						opts->in_capsule_data_size,
804 						IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
805 	}
806 
807 	if (!resources->cmds_mr || !resources->cpls_mr ||
808 	    (opts->in_capsule_data_size &&
809 	     !resources->bufs_mr)) {
810 		goto cleanup;
811 	}
812 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Command Array: %p Length: %lx LKey: %x\n",
813 		      resources->cmds, opts->max_queue_depth * sizeof(*resources->cmds),
814 		      resources->cmds_mr->lkey);
815 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Completion Array: %p Length: %lx LKey: %x\n",
816 		      resources->cpls, opts->max_queue_depth * sizeof(*resources->cpls),
817 		      resources->cpls_mr->lkey);
818 	if (resources->bufs && resources->bufs_mr) {
819 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "In Capsule Data Array: %p Length: %x LKey: %x\n",
820 			      resources->bufs, opts->max_queue_depth *
821 			      opts->in_capsule_data_size, resources->bufs_mr->lkey);
822 	}
823 
824 	/* Initialize queues */
825 	STAILQ_INIT(&resources->incoming_queue);
826 	STAILQ_INIT(&resources->free_queue);
827 
828 	for (i = 0; i < opts->max_queue_depth; i++) {
829 		struct ibv_recv_wr *bad_wr = NULL;
830 
831 		rdma_recv = &resources->recvs[i];
832 		rdma_recv->qpair = opts->qpair;
833 
834 		/* Set up memory to receive commands */
835 		if (resources->bufs) {
836 			rdma_recv->buf = (void *)((uintptr_t)resources->bufs + (i *
837 						  opts->in_capsule_data_size));
838 		}
839 
840 		rdma_recv->rdma_wr.type = RDMA_WR_TYPE_RECV;
841 
842 		rdma_recv->sgl[0].addr = (uintptr_t)&resources->cmds[i];
843 		rdma_recv->sgl[0].length = sizeof(resources->cmds[i]);
844 		rdma_recv->sgl[0].lkey = resources->cmds_mr->lkey;
845 		rdma_recv->wr.num_sge = 1;
846 
847 		if (rdma_recv->buf && resources->bufs_mr) {
848 			rdma_recv->sgl[1].addr = (uintptr_t)rdma_recv->buf;
849 			rdma_recv->sgl[1].length = opts->in_capsule_data_size;
850 			rdma_recv->sgl[1].lkey = resources->bufs_mr->lkey;
851 			rdma_recv->wr.num_sge++;
852 		}
853 
854 		rdma_recv->wr.wr_id = (uintptr_t)&rdma_recv->rdma_wr;
855 		rdma_recv->wr.sg_list = rdma_recv->sgl;
856 		if (opts->shared) {
857 			srq = (struct ibv_srq *)opts->qp;
858 			rc = ibv_post_srq_recv(srq, &rdma_recv->wr, &bad_wr);
859 		} else {
860 			qp = (struct ibv_qp *)opts->qp;
861 			rc = ibv_post_recv(qp, &rdma_recv->wr, &bad_wr);
862 		}
863 		if (rc) {
864 			goto cleanup;
865 		}
866 	}
867 
868 	for (i = 0; i < opts->max_queue_depth; i++) {
869 		rdma_req = &resources->reqs[i];
870 
871 		if (opts->qpair != NULL) {
872 			rdma_req->req.qpair = &opts->qpair->qpair;
873 		} else {
874 			rdma_req->req.qpair = NULL;
875 		}
876 		rdma_req->req.cmd = NULL;
877 
878 		/* Set up memory to send responses */
879 		rdma_req->req.rsp = &resources->cpls[i];
880 
881 		rdma_req->rsp.sgl[0].addr = (uintptr_t)&resources->cpls[i];
882 		rdma_req->rsp.sgl[0].length = sizeof(resources->cpls[i]);
883 		rdma_req->rsp.sgl[0].lkey = resources->cpls_mr->lkey;
884 
885 		rdma_req->rsp.rdma_wr.type = RDMA_WR_TYPE_SEND;
886 		rdma_req->rsp.wr.wr_id = (uintptr_t)&rdma_req->rsp.rdma_wr;
887 		rdma_req->rsp.wr.next = NULL;
888 		rdma_req->rsp.wr.opcode = IBV_WR_SEND;
889 		rdma_req->rsp.wr.send_flags = IBV_SEND_SIGNALED;
890 		rdma_req->rsp.wr.sg_list = rdma_req->rsp.sgl;
891 		rdma_req->rsp.wr.num_sge = SPDK_COUNTOF(rdma_req->rsp.sgl);
892 
893 		/* Set up memory for data buffers */
894 		rdma_req->data.rdma_wr.type = RDMA_WR_TYPE_DATA;
895 		rdma_req->data.wr.wr_id = (uintptr_t)&rdma_req->data.rdma_wr;
896 		rdma_req->data.wr.next = NULL;
897 		rdma_req->data.wr.send_flags = IBV_SEND_SIGNALED;
898 		rdma_req->data.wr.sg_list = rdma_req->data.sgl;
899 		rdma_req->data.wr.num_sge = SPDK_COUNTOF(rdma_req->data.sgl);
900 
901 		/* Initialize request state to FREE */
902 		rdma_req->state = RDMA_REQUEST_STATE_FREE;
903 		STAILQ_INSERT_TAIL(&resources->free_queue, rdma_req, state_link);
904 	}
905 
906 	return resources;
907 
908 cleanup:
909 	nvmf_rdma_resources_destroy(resources);
910 	return NULL;
911 }
912 
913 static void
914 spdk_nvmf_rdma_qpair_clean_ibv_events(struct spdk_nvmf_rdma_qpair *rqpair)
915 {
916 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx, *tctx;
917 	STAILQ_FOREACH_SAFE(ctx, &rqpair->ibv_events, link, tctx) {
918 		ctx->rqpair = NULL;
919 		/* Memory allocated for ctx is freed in spdk_nvmf_rdma_qpair_process_ibv_event */
920 		STAILQ_REMOVE(&rqpair->ibv_events, ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
921 	}
922 }
923 
924 static void
925 spdk_nvmf_rdma_qpair_destroy(struct spdk_nvmf_rdma_qpair *rqpair)
926 {
927 	struct spdk_nvmf_rdma_recv	*rdma_recv, *recv_tmp;
928 	struct ibv_recv_wr		*bad_recv_wr = NULL;
929 	int				rc;
930 
931 	spdk_trace_record(TRACE_RDMA_QP_DESTROY, 0, 0, (uintptr_t)rqpair->cm_id, 0);
932 
933 	spdk_poller_unregister(&rqpair->destruct_poller);
934 
935 	if (rqpair->qd != 0) {
936 		if (rqpair->srq == NULL) {
937 			nvmf_rdma_dump_qpair_contents(rqpair);
938 		}
939 		SPDK_WARNLOG("Destroying qpair when queue depth is %d\n", rqpair->qd);
940 	}
941 
942 	if (rqpair->poller) {
943 		TAILQ_REMOVE(&rqpair->poller->qpairs, rqpair, link);
944 
945 		if (rqpair->srq != NULL && rqpair->resources != NULL) {
946 			/* Drop all received but unprocessed commands for this queue and return them to SRQ */
947 			STAILQ_FOREACH_SAFE(rdma_recv, &rqpair->resources->incoming_queue, link, recv_tmp) {
948 				if (rqpair == rdma_recv->qpair) {
949 					STAILQ_REMOVE(&rqpair->resources->incoming_queue, rdma_recv, spdk_nvmf_rdma_recv, link);
950 					rc = ibv_post_srq_recv(rqpair->srq, &rdma_recv->wr, &bad_recv_wr);
951 					if (rc) {
952 						SPDK_ERRLOG("Unable to re-post rx descriptor\n");
953 					}
954 				}
955 			}
956 		}
957 	}
958 
959 	if (rqpair->cm_id) {
960 		if (rqpair->cm_id->qp != NULL) {
961 			rdma_destroy_qp(rqpair->cm_id);
962 		}
963 		rdma_destroy_id(rqpair->cm_id);
964 
965 		if (rqpair->poller != NULL && rqpair->srq == NULL) {
966 			rqpair->poller->required_num_wr -= MAX_WR_PER_QP(rqpair->max_queue_depth);
967 		}
968 	}
969 
970 	if (rqpair->srq == NULL && rqpair->resources != NULL) {
971 		nvmf_rdma_resources_destroy(rqpair->resources);
972 	}
973 
974 	spdk_nvmf_rdma_qpair_clean_ibv_events(rqpair);
975 
976 	free(rqpair);
977 }
978 
979 static int
980 nvmf_rdma_resize_cq(struct spdk_nvmf_rdma_qpair *rqpair, struct spdk_nvmf_rdma_device *device)
981 {
982 	struct spdk_nvmf_rdma_poller	*rpoller;
983 	int				rc, num_cqe, required_num_wr;
984 
985 	/* Enlarge CQ size dynamically */
986 	rpoller = rqpair->poller;
987 	required_num_wr = rpoller->required_num_wr + MAX_WR_PER_QP(rqpair->max_queue_depth);
988 	num_cqe = rpoller->num_cqe;
989 	if (num_cqe < required_num_wr) {
990 		num_cqe = spdk_max(num_cqe * 2, required_num_wr);
991 		num_cqe = spdk_min(num_cqe, device->attr.max_cqe);
992 	}
993 
994 	if (rpoller->num_cqe != num_cqe) {
995 		if (required_num_wr > device->attr.max_cqe) {
996 			SPDK_ERRLOG("RDMA CQE requirement (%d) exceeds device max_cqe limitation (%d)\n",
997 				    required_num_wr, device->attr.max_cqe);
998 			return -1;
999 		}
1000 
1001 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Resize RDMA CQ from %d to %d\n", rpoller->num_cqe, num_cqe);
1002 		rc = ibv_resize_cq(rpoller->cq, num_cqe);
1003 		if (rc) {
1004 			SPDK_ERRLOG("RDMA CQ resize failed: errno %d: %s\n", errno, spdk_strerror(errno));
1005 			return -1;
1006 		}
1007 
1008 		rpoller->num_cqe = num_cqe;
1009 	}
1010 
1011 	rpoller->required_num_wr = required_num_wr;
1012 	return 0;
1013 }
1014 
1015 static int
1016 spdk_nvmf_rdma_qpair_initialize(struct spdk_nvmf_qpair *qpair)
1017 {
1018 	struct spdk_nvmf_rdma_qpair		*rqpair;
1019 	int					rc;
1020 	struct spdk_nvmf_rdma_transport		*rtransport;
1021 	struct spdk_nvmf_transport		*transport;
1022 	struct spdk_nvmf_rdma_resource_opts	opts;
1023 	struct spdk_nvmf_rdma_device		*device;
1024 	struct ibv_qp_init_attr			ibv_init_attr;
1025 
1026 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1027 	device = rqpair->port->device;
1028 
1029 	memset(&ibv_init_attr, 0, sizeof(struct ibv_qp_init_attr));
1030 	ibv_init_attr.qp_context	= rqpair;
1031 	ibv_init_attr.qp_type		= IBV_QPT_RC;
1032 	ibv_init_attr.send_cq		= rqpair->poller->cq;
1033 	ibv_init_attr.recv_cq		= rqpair->poller->cq;
1034 
1035 	if (rqpair->srq) {
1036 		ibv_init_attr.srq		= rqpair->srq;
1037 	} else {
1038 		ibv_init_attr.cap.max_recv_wr	= rqpair->max_queue_depth +
1039 						  1; /* RECV operations + dummy drain WR */
1040 	}
1041 
1042 	ibv_init_attr.cap.max_send_wr	= rqpair->max_queue_depth *
1043 					  2 + 1; /* SEND, READ, and WRITE operations + dummy drain WR */
1044 	ibv_init_attr.cap.max_send_sge	= spdk_min(device->attr.max_sge, NVMF_DEFAULT_TX_SGE);
1045 	ibv_init_attr.cap.max_recv_sge	= spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
1046 
1047 	if (rqpair->srq == NULL && nvmf_rdma_resize_cq(rqpair, device) < 0) {
1048 		SPDK_ERRLOG("Failed to resize the completion queue. Cannot initialize qpair.\n");
1049 		goto error;
1050 	}
1051 
1052 	rc = rdma_create_qp(rqpair->cm_id, rqpair->port->device->pd, &ibv_init_attr);
1053 	if (rc) {
1054 		SPDK_ERRLOG("rdma_create_qp failed: errno %d: %s\n", errno, spdk_strerror(errno));
1055 		goto error;
1056 	}
1057 
1058 	rqpair->max_send_depth = spdk_min((uint32_t)(rqpair->max_queue_depth * 2 + 1),
1059 					  ibv_init_attr.cap.max_send_wr);
1060 	rqpair->max_send_sge = spdk_min(NVMF_DEFAULT_TX_SGE, ibv_init_attr.cap.max_send_sge);
1061 	rqpair->max_recv_sge = spdk_min(NVMF_DEFAULT_RX_SGE, ibv_init_attr.cap.max_recv_sge);
1062 	spdk_trace_record(TRACE_RDMA_QP_CREATE, 0, 0, (uintptr_t)rqpair->cm_id, 0);
1063 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "New RDMA Connection: %p\n", qpair);
1064 
1065 	rqpair->sends_to_post.first = NULL;
1066 	rqpair->sends_to_post.last = NULL;
1067 
1068 	if (rqpair->poller->srq == NULL) {
1069 		rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
1070 		transport = &rtransport->transport;
1071 
1072 		opts.qp = rqpair->cm_id->qp;
1073 		opts.pd = rqpair->cm_id->pd;
1074 		opts.qpair = rqpair;
1075 		opts.shared = false;
1076 		opts.max_queue_depth = rqpair->max_queue_depth;
1077 		opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
1078 
1079 		rqpair->resources = nvmf_rdma_resources_create(&opts);
1080 
1081 		if (!rqpair->resources) {
1082 			SPDK_ERRLOG("Unable to allocate resources for receive queue.\n");
1083 			rdma_destroy_qp(rqpair->cm_id);
1084 			goto error;
1085 		}
1086 	} else {
1087 		rqpair->resources = rqpair->poller->resources;
1088 	}
1089 
1090 	rqpair->current_recv_depth = 0;
1091 	STAILQ_INIT(&rqpair->pending_rdma_read_queue);
1092 	STAILQ_INIT(&rqpair->pending_rdma_write_queue);
1093 
1094 	return 0;
1095 
1096 error:
1097 	rdma_destroy_id(rqpair->cm_id);
1098 	rqpair->cm_id = NULL;
1099 	return -1;
1100 }
1101 
1102 /* Append the given recv wr structure to the resource structs outstanding recvs list. */
1103 /* This function accepts either a single wr or the first wr in a linked list. */
1104 static void
1105 nvmf_rdma_qpair_queue_recv_wrs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *first)
1106 {
1107 	struct ibv_recv_wr *last;
1108 
1109 	last = first;
1110 	while (last->next != NULL) {
1111 		last = last->next;
1112 	}
1113 
1114 	if (rqpair->resources->recvs_to_post.first == NULL) {
1115 		rqpair->resources->recvs_to_post.first = first;
1116 		rqpair->resources->recvs_to_post.last = last;
1117 		if (rqpair->srq == NULL) {
1118 			STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_recv, rqpair, recv_link);
1119 		}
1120 	} else {
1121 		rqpair->resources->recvs_to_post.last->next = first;
1122 		rqpair->resources->recvs_to_post.last = last;
1123 	}
1124 }
1125 
1126 /* Append the given send wr structure to the qpair's outstanding sends list. */
1127 /* This function accepts either a single wr or the first wr in a linked list. */
1128 static void
1129 nvmf_rdma_qpair_queue_send_wrs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_send_wr *first)
1130 {
1131 	struct ibv_send_wr *last;
1132 
1133 	last = first;
1134 	while (last->next != NULL) {
1135 		last = last->next;
1136 	}
1137 
1138 	if (rqpair->sends_to_post.first == NULL) {
1139 		rqpair->sends_to_post.first = first;
1140 		rqpair->sends_to_post.last = last;
1141 		STAILQ_INSERT_TAIL(&rqpair->poller->qpairs_pending_send, rqpair, send_link);
1142 	} else {
1143 		rqpair->sends_to_post.last->next = first;
1144 		rqpair->sends_to_post.last = last;
1145 	}
1146 }
1147 
1148 static int
1149 request_transfer_in(struct spdk_nvmf_request *req)
1150 {
1151 	struct spdk_nvmf_rdma_request	*rdma_req;
1152 	struct spdk_nvmf_qpair		*qpair;
1153 	struct spdk_nvmf_rdma_qpair	*rqpair;
1154 
1155 	qpair = req->qpair;
1156 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1157 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1158 
1159 	assert(req->xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
1160 	assert(rdma_req != NULL);
1161 
1162 	nvmf_rdma_qpair_queue_send_wrs(rqpair, &rdma_req->data.wr);
1163 	rqpair->current_read_depth += rdma_req->num_outstanding_data_wr;
1164 	rqpair->current_send_depth += rdma_req->num_outstanding_data_wr;
1165 	return 0;
1166 }
1167 
1168 static int
1169 request_transfer_out(struct spdk_nvmf_request *req, int *data_posted)
1170 {
1171 	int				num_outstanding_data_wr = 0;
1172 	struct spdk_nvmf_rdma_request	*rdma_req;
1173 	struct spdk_nvmf_qpair		*qpair;
1174 	struct spdk_nvmf_rdma_qpair	*rqpair;
1175 	struct spdk_nvme_cpl		*rsp;
1176 	struct ibv_send_wr		*first = NULL;
1177 
1178 	*data_posted = 0;
1179 	qpair = req->qpair;
1180 	rsp = &req->rsp->nvme_cpl;
1181 	rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
1182 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
1183 
1184 	/* Advance our sq_head pointer */
1185 	if (qpair->sq_head == qpair->sq_head_max) {
1186 		qpair->sq_head = 0;
1187 	} else {
1188 		qpair->sq_head++;
1189 	}
1190 	rsp->sqhd = qpair->sq_head;
1191 
1192 	/* queue the capsule for the recv buffer */
1193 	assert(rdma_req->recv != NULL);
1194 
1195 	nvmf_rdma_qpair_queue_recv_wrs(rqpair, &rdma_req->recv->wr);
1196 
1197 	rdma_req->recv = NULL;
1198 	assert(rqpair->current_recv_depth > 0);
1199 	rqpair->current_recv_depth--;
1200 
1201 	/* Build the response which consists of optional
1202 	 * RDMA WRITEs to transfer data, plus an RDMA SEND
1203 	 * containing the response.
1204 	 */
1205 	first = &rdma_req->rsp.wr;
1206 
1207 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
1208 	    req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1209 		first = &rdma_req->data.wr;
1210 		*data_posted = 1;
1211 		num_outstanding_data_wr = rdma_req->num_outstanding_data_wr;
1212 	}
1213 	nvmf_rdma_qpair_queue_send_wrs(rqpair, first);
1214 	/* +1 for the rsp wr */
1215 	rqpair->current_send_depth += num_outstanding_data_wr + 1;
1216 
1217 	return 0;
1218 }
1219 
1220 static int
1221 spdk_nvmf_rdma_event_accept(struct rdma_cm_id *id, struct spdk_nvmf_rdma_qpair *rqpair)
1222 {
1223 	struct spdk_nvmf_rdma_accept_private_data	accept_data;
1224 	struct rdma_conn_param				ctrlr_event_data = {};
1225 	int						rc;
1226 
1227 	accept_data.recfmt = 0;
1228 	accept_data.crqsize = rqpair->max_queue_depth;
1229 
1230 	ctrlr_event_data.private_data = &accept_data;
1231 	ctrlr_event_data.private_data_len = sizeof(accept_data);
1232 	if (id->ps == RDMA_PS_TCP) {
1233 		ctrlr_event_data.responder_resources = 0; /* We accept 0 reads from the host */
1234 		ctrlr_event_data.initiator_depth = rqpair->max_read_depth;
1235 	}
1236 
1237 	/* Configure infinite retries for the initiator side qpair.
1238 	 * When using a shared receive queue on the target side,
1239 	 * we need to pass this value to the initiator to prevent the
1240 	 * initiator side NIC from completing SEND requests back to the
1241 	 * initiator with status rnr_retry_count_exceeded. */
1242 	if (rqpair->srq != NULL) {
1243 		ctrlr_event_data.rnr_retry_count = 0x7;
1244 	}
1245 
1246 	rc = rdma_accept(id, &ctrlr_event_data);
1247 	if (rc) {
1248 		SPDK_ERRLOG("Error %d on rdma_accept\n", errno);
1249 	} else {
1250 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Sent back the accept\n");
1251 	}
1252 
1253 	return rc;
1254 }
1255 
1256 static void
1257 spdk_nvmf_rdma_event_reject(struct rdma_cm_id *id, enum spdk_nvmf_rdma_transport_error error)
1258 {
1259 	struct spdk_nvmf_rdma_reject_private_data	rej_data;
1260 
1261 	rej_data.recfmt = 0;
1262 	rej_data.sts = error;
1263 
1264 	rdma_reject(id, &rej_data, sizeof(rej_data));
1265 }
1266 
1267 static int
1268 nvmf_rdma_connect(struct spdk_nvmf_transport *transport, struct rdma_cm_event *event,
1269 		  new_qpair_fn cb_fn, void *cb_arg)
1270 {
1271 	struct spdk_nvmf_rdma_transport *rtransport;
1272 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
1273 	struct spdk_nvmf_rdma_port	*port;
1274 	struct rdma_conn_param		*rdma_param = NULL;
1275 	const struct spdk_nvmf_rdma_request_private_data *private_data = NULL;
1276 	uint16_t			max_queue_depth;
1277 	uint16_t			max_read_depth;
1278 
1279 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
1280 
1281 	assert(event->id != NULL); /* Impossible. Can't even reject the connection. */
1282 	assert(event->id->verbs != NULL); /* Impossible. No way to handle this. */
1283 
1284 	rdma_param = &event->param.conn;
1285 	if (rdma_param->private_data == NULL ||
1286 	    rdma_param->private_data_len < sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1287 		SPDK_ERRLOG("connect request: no private data provided\n");
1288 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_PRIVATE_DATA_LENGTH);
1289 		return -1;
1290 	}
1291 
1292 	private_data = rdma_param->private_data;
1293 	if (private_data->recfmt != 0) {
1294 		SPDK_ERRLOG("Received RDMA private data with RECFMT != 0\n");
1295 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_INVALID_RECFMT);
1296 		return -1;
1297 	}
1298 
1299 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Connect Recv on fabric intf name %s, dev_name %s\n",
1300 		      event->id->verbs->device->name, event->id->verbs->device->dev_name);
1301 
1302 	port = event->listen_id->context;
1303 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Listen Id was %p with verbs %p. ListenAddr: %p\n",
1304 		      event->listen_id, event->listen_id->verbs, port);
1305 
1306 	/* Figure out the supported queue depth. This is a multi-step process
1307 	 * that takes into account hardware maximums, host provided values,
1308 	 * and our target's internal memory limits */
1309 
1310 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Calculating Queue Depth\n");
1311 
1312 	/* Start with the maximum queue depth allowed by the target */
1313 	max_queue_depth = rtransport->transport.opts.max_queue_depth;
1314 	max_read_depth = rtransport->transport.opts.max_queue_depth;
1315 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Target Max Queue Depth: %d\n",
1316 		      rtransport->transport.opts.max_queue_depth);
1317 
1318 	/* Next check the local NIC's hardware limitations */
1319 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
1320 		      "Local NIC Max Send/Recv Queue Depth: %d Max Read/Write Queue Depth: %d\n",
1321 		      port->device->attr.max_qp_wr, port->device->attr.max_qp_rd_atom);
1322 	max_queue_depth = spdk_min(max_queue_depth, port->device->attr.max_qp_wr);
1323 	max_read_depth = spdk_min(max_read_depth, port->device->attr.max_qp_init_rd_atom);
1324 
1325 	/* Next check the remote NIC's hardware limitations */
1326 	SPDK_DEBUGLOG(SPDK_LOG_RDMA,
1327 		      "Host (Initiator) NIC Max Incoming RDMA R/W operations: %d Max Outgoing RDMA R/W operations: %d\n",
1328 		      rdma_param->initiator_depth, rdma_param->responder_resources);
1329 	if (rdma_param->initiator_depth > 0) {
1330 		max_read_depth = spdk_min(max_read_depth, rdma_param->initiator_depth);
1331 	}
1332 
1333 	/* Finally check for the host software requested values, which are
1334 	 * optional. */
1335 	if (rdma_param->private_data != NULL &&
1336 	    rdma_param->private_data_len >= sizeof(struct spdk_nvmf_rdma_request_private_data)) {
1337 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Receive Queue Size: %d\n", private_data->hrqsize);
1338 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Host Send Queue Size: %d\n", private_data->hsqsize);
1339 		max_queue_depth = spdk_min(max_queue_depth, private_data->hrqsize);
1340 		max_queue_depth = spdk_min(max_queue_depth, private_data->hsqsize + 1);
1341 	}
1342 
1343 	SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Final Negotiated Queue Depth: %d R/W Depth: %d\n",
1344 		      max_queue_depth, max_read_depth);
1345 
1346 	rqpair = calloc(1, sizeof(struct spdk_nvmf_rdma_qpair));
1347 	if (rqpair == NULL) {
1348 		SPDK_ERRLOG("Could not allocate new connection.\n");
1349 		spdk_nvmf_rdma_event_reject(event->id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
1350 		return -1;
1351 	}
1352 
1353 	rqpair->port = port;
1354 	rqpair->max_queue_depth = max_queue_depth;
1355 	rqpair->max_read_depth = max_read_depth;
1356 	rqpair->cm_id = event->id;
1357 	rqpair->listen_id = event->listen_id;
1358 	rqpair->qpair.transport = transport;
1359 	STAILQ_INIT(&rqpair->ibv_events);
1360 	/* use qid from the private data to determine the qpair type
1361 	   qid will be set to the appropriate value when the controller is created */
1362 	rqpair->qpair.qid = private_data->qid;
1363 
1364 	event->id->context = &rqpair->qpair;
1365 
1366 	cb_fn(&rqpair->qpair, cb_arg);
1367 
1368 	return 0;
1369 }
1370 
1371 static int
1372 spdk_nvmf_rdma_mem_notify(void *cb_ctx, struct spdk_mem_map *map,
1373 			  enum spdk_mem_map_notify_action action,
1374 			  void *vaddr, size_t size)
1375 {
1376 	struct ibv_pd *pd = cb_ctx;
1377 	struct ibv_mr *mr;
1378 	int rc;
1379 
1380 	switch (action) {
1381 	case SPDK_MEM_MAP_NOTIFY_REGISTER:
1382 		if (!g_nvmf_hooks.get_rkey) {
1383 			mr = ibv_reg_mr(pd, vaddr, size,
1384 					IBV_ACCESS_LOCAL_WRITE |
1385 					IBV_ACCESS_REMOTE_READ |
1386 					IBV_ACCESS_REMOTE_WRITE);
1387 			if (mr == NULL) {
1388 				SPDK_ERRLOG("ibv_reg_mr() failed\n");
1389 				return -1;
1390 			} else {
1391 				rc = spdk_mem_map_set_translation(map, (uint64_t)vaddr, size, (uint64_t)mr);
1392 			}
1393 		} else {
1394 			rc = spdk_mem_map_set_translation(map, (uint64_t)vaddr, size,
1395 							  g_nvmf_hooks.get_rkey(pd, vaddr, size));
1396 		}
1397 		break;
1398 	case SPDK_MEM_MAP_NOTIFY_UNREGISTER:
1399 		if (!g_nvmf_hooks.get_rkey) {
1400 			mr = (struct ibv_mr *)spdk_mem_map_translate(map, (uint64_t)vaddr, NULL);
1401 			if (mr) {
1402 				ibv_dereg_mr(mr);
1403 			}
1404 		}
1405 		rc = spdk_mem_map_clear_translation(map, (uint64_t)vaddr, size);
1406 		break;
1407 	default:
1408 		SPDK_UNREACHABLE();
1409 	}
1410 
1411 	return rc;
1412 }
1413 
1414 static int
1415 spdk_nvmf_rdma_check_contiguous_entries(uint64_t addr_1, uint64_t addr_2)
1416 {
1417 	/* Two contiguous mappings will point to the same address which is the start of the RDMA MR. */
1418 	return addr_1 == addr_2;
1419 }
1420 
1421 static inline void
1422 nvmf_rdma_setup_wr(struct ibv_send_wr *wr, struct ibv_send_wr *next,
1423 		   enum spdk_nvme_data_transfer xfer)
1424 {
1425 	if (xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
1426 		wr->opcode = IBV_WR_RDMA_WRITE;
1427 		wr->send_flags = 0;
1428 		wr->next = next;
1429 	} else if (xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
1430 		wr->opcode = IBV_WR_RDMA_READ;
1431 		wr->send_flags = IBV_SEND_SIGNALED;
1432 		wr->next = NULL;
1433 	} else {
1434 		assert(0);
1435 	}
1436 }
1437 
1438 static int
1439 nvmf_request_alloc_wrs(struct spdk_nvmf_rdma_transport *rtransport,
1440 		       struct spdk_nvmf_rdma_request *rdma_req,
1441 		       uint32_t num_sgl_descriptors)
1442 {
1443 	struct spdk_nvmf_rdma_request_data	*work_requests[SPDK_NVMF_MAX_SGL_ENTRIES];
1444 	struct spdk_nvmf_rdma_request_data	*current_data_wr;
1445 	uint32_t				i;
1446 
1447 	if (num_sgl_descriptors > SPDK_NVMF_MAX_SGL_ENTRIES) {
1448 		SPDK_ERRLOG("Requested too much entries (%u), the limit is %u\n",
1449 			    num_sgl_descriptors, SPDK_NVMF_MAX_SGL_ENTRIES);
1450 		return -EINVAL;
1451 	}
1452 
1453 	if (spdk_mempool_get_bulk(rtransport->data_wr_pool, (void **)work_requests, num_sgl_descriptors)) {
1454 		return -ENOMEM;
1455 	}
1456 
1457 	current_data_wr = &rdma_req->data;
1458 
1459 	for (i = 0; i < num_sgl_descriptors; i++) {
1460 		nvmf_rdma_setup_wr(&current_data_wr->wr, &work_requests[i]->wr, rdma_req->req.xfer);
1461 		current_data_wr->wr.next = &work_requests[i]->wr;
1462 		current_data_wr = work_requests[i];
1463 		current_data_wr->wr.sg_list = current_data_wr->sgl;
1464 		current_data_wr->wr.wr_id = rdma_req->data.wr.wr_id;
1465 	}
1466 
1467 	nvmf_rdma_setup_wr(&current_data_wr->wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1468 
1469 	return 0;
1470 }
1471 
1472 static inline void
1473 nvmf_rdma_setup_request(struct spdk_nvmf_rdma_request *rdma_req)
1474 {
1475 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1476 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1477 
1478 	wr->wr.rdma.rkey = sgl->keyed.key;
1479 	wr->wr.rdma.remote_addr = sgl->address;
1480 	nvmf_rdma_setup_wr(wr, &rdma_req->rsp.wr, rdma_req->req.xfer);
1481 }
1482 
1483 static inline void
1484 nvmf_rdma_update_remote_addr(struct spdk_nvmf_rdma_request *rdma_req, uint32_t num_wrs)
1485 {
1486 	struct ibv_send_wr		*wr = &rdma_req->data.wr;
1487 	struct spdk_nvme_sgl_descriptor	*sgl = &rdma_req->req.cmd->nvme_cmd.dptr.sgl1;
1488 	uint32_t			i;
1489 	int				j;
1490 	uint64_t			remote_addr_offset = 0;
1491 
1492 	for (i = 0; i < num_wrs; ++i) {
1493 		wr->wr.rdma.rkey = sgl->keyed.key;
1494 		wr->wr.rdma.remote_addr = sgl->address + remote_addr_offset;
1495 		for (j = 0; j < wr->num_sge; ++j) {
1496 			remote_addr_offset += wr->sg_list[j].length;
1497 		}
1498 		wr = wr->next;
1499 	}
1500 }
1501 
1502 /* This function is used in the rare case that we have a buffer split over multiple memory regions. */
1503 static int
1504 nvmf_rdma_replace_buffer(struct spdk_nvmf_rdma_poll_group *rgroup, void **buf)
1505 {
1506 	struct spdk_nvmf_transport_poll_group	*group = &rgroup->group;
1507 	struct spdk_nvmf_transport		*transport = group->transport;
1508 	struct spdk_nvmf_transport_pg_cache_buf	*old_buf;
1509 	void					*new_buf;
1510 
1511 	if (!(STAILQ_EMPTY(&group->buf_cache))) {
1512 		group->buf_cache_count--;
1513 		new_buf = STAILQ_FIRST(&group->buf_cache);
1514 		STAILQ_REMOVE_HEAD(&group->buf_cache, link);
1515 		assert(*buf != NULL);
1516 	} else {
1517 		new_buf = spdk_mempool_get(transport->data_buf_pool);
1518 	}
1519 
1520 	if (*buf == NULL) {
1521 		return -ENOMEM;
1522 	}
1523 
1524 	old_buf = *buf;
1525 	STAILQ_INSERT_HEAD(&rgroup->retired_bufs, old_buf, link);
1526 	*buf = new_buf;
1527 	return 0;
1528 }
1529 
1530 static bool
1531 nvmf_rdma_get_lkey(struct spdk_nvmf_rdma_device *device, struct iovec *iov,
1532 		   uint32_t *_lkey)
1533 {
1534 	uint64_t	translation_len;
1535 	uint32_t	lkey;
1536 
1537 	translation_len = iov->iov_len;
1538 
1539 	if (!g_nvmf_hooks.get_rkey) {
1540 		lkey = ((struct ibv_mr *)spdk_mem_map_translate(device->map,
1541 				(uint64_t)iov->iov_base, &translation_len))->lkey;
1542 	} else {
1543 		lkey = spdk_mem_map_translate(device->map,
1544 					      (uint64_t)iov->iov_base, &translation_len);
1545 	}
1546 
1547 	if (spdk_unlikely(translation_len < iov->iov_len)) {
1548 		return false;
1549 	}
1550 
1551 	*_lkey = lkey;
1552 	return true;
1553 }
1554 
1555 static bool
1556 nvmf_rdma_fill_wr_sge(struct spdk_nvmf_rdma_device *device,
1557 		      struct iovec *iov, struct ibv_send_wr **_wr,
1558 		      uint32_t *_remaining_data_block, uint32_t *_offset,
1559 		      uint32_t *_num_extra_wrs,
1560 		      const struct spdk_dif_ctx *dif_ctx)
1561 {
1562 	struct ibv_send_wr *wr = *_wr;
1563 	struct ibv_sge	*sg_ele = &wr->sg_list[wr->num_sge];
1564 	uint32_t	lkey = 0;
1565 	uint32_t	remaining, data_block_size, md_size, sge_len;
1566 
1567 	if (spdk_unlikely(!nvmf_rdma_get_lkey(device, iov, &lkey))) {
1568 		/* This is a very rare case that can occur when using DPDK version < 19.05 */
1569 		SPDK_ERRLOG("Data buffer split over multiple RDMA Memory Regions. Removing it from circulation.\n");
1570 		return false;
1571 	}
1572 
1573 	if (spdk_likely(!dif_ctx)) {
1574 		sg_ele->lkey = lkey;
1575 		sg_ele->addr = (uintptr_t)(iov->iov_base);
1576 		sg_ele->length = iov->iov_len;
1577 		wr->num_sge++;
1578 	} else {
1579 		remaining = iov->iov_len - *_offset;
1580 		data_block_size = dif_ctx->block_size - dif_ctx->md_size;
1581 		md_size = dif_ctx->md_size;
1582 
1583 		while (remaining) {
1584 			if (wr->num_sge >= SPDK_NVMF_MAX_SGL_ENTRIES) {
1585 				if (*_num_extra_wrs > 0 && wr->next) {
1586 					*_wr = wr->next;
1587 					wr = *_wr;
1588 					wr->num_sge = 0;
1589 					sg_ele = &wr->sg_list[wr->num_sge];
1590 					(*_num_extra_wrs)--;
1591 				} else {
1592 					break;
1593 				}
1594 			}
1595 			sg_ele->lkey = lkey;
1596 			sg_ele->addr = (uintptr_t)((char *)iov->iov_base + *_offset);
1597 			sge_len = spdk_min(remaining, *_remaining_data_block);
1598 			sg_ele->length = sge_len;
1599 			remaining -= sge_len;
1600 			*_remaining_data_block -= sge_len;
1601 			*_offset += sge_len;
1602 
1603 			sg_ele++;
1604 			wr->num_sge++;
1605 
1606 			if (*_remaining_data_block == 0) {
1607 				/* skip metadata */
1608 				*_offset += md_size;
1609 				/* Metadata that do not fit this IO buffer will be included in the next IO buffer */
1610 				remaining -= spdk_min(remaining, md_size);
1611 				*_remaining_data_block = data_block_size;
1612 			}
1613 
1614 			if (remaining == 0) {
1615 				/* By subtracting the size of the last IOV from the offset, we ensure that we skip
1616 				   the remaining metadata bits at the beginning of the next buffer */
1617 				*_offset -= iov->iov_len;
1618 			}
1619 		}
1620 	}
1621 
1622 	return true;
1623 }
1624 
1625 static int
1626 nvmf_rdma_fill_wr_sgl(struct spdk_nvmf_rdma_poll_group *rgroup,
1627 		      struct spdk_nvmf_rdma_device *device,
1628 		      struct spdk_nvmf_rdma_request *rdma_req,
1629 		      struct ibv_send_wr *wr,
1630 		      uint32_t length,
1631 		      uint32_t num_extra_wrs)
1632 {
1633 	struct spdk_nvmf_request *req = &rdma_req->req;
1634 	struct spdk_dif_ctx *dif_ctx = NULL;
1635 	uint32_t remaining_data_block = 0;
1636 	uint32_t offset = 0;
1637 
1638 	if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
1639 		dif_ctx = &rdma_req->req.dif.dif_ctx;
1640 		remaining_data_block = dif_ctx->block_size - dif_ctx->md_size;
1641 	}
1642 
1643 	wr->num_sge = 0;
1644 
1645 	while (length && (num_extra_wrs || wr->num_sge < SPDK_NVMF_MAX_SGL_ENTRIES)) {
1646 		while (spdk_unlikely(!nvmf_rdma_fill_wr_sge(device, &req->iov[rdma_req->iovpos], &wr,
1647 				     &remaining_data_block, &offset, &num_extra_wrs, dif_ctx))) {
1648 			if (nvmf_rdma_replace_buffer(rgroup, &req->buffers[rdma_req->iovpos]) == -ENOMEM) {
1649 				return -ENOMEM;
1650 			}
1651 			req->iov[rdma_req->iovpos].iov_base = (void *)((uintptr_t)(req->buffers[rdma_req->iovpos] +
1652 							      NVMF_DATA_BUFFER_MASK) &
1653 							      ~NVMF_DATA_BUFFER_MASK);
1654 		}
1655 
1656 		length -= req->iov[rdma_req->iovpos].iov_len;
1657 		rdma_req->iovpos++;
1658 	}
1659 
1660 	if (length) {
1661 		SPDK_ERRLOG("Not enough SG entries to hold data buffer\n");
1662 		return -EINVAL;
1663 	}
1664 
1665 	return 0;
1666 }
1667 
1668 static inline uint32_t
1669 nvmf_rdma_calc_num_wrs(uint32_t length, uint32_t io_unit_size, uint32_t block_size)
1670 {
1671 	/* estimate the number of SG entries and WRs needed to process the request */
1672 	uint32_t num_sge = 0;
1673 	uint32_t i;
1674 	uint32_t num_buffers = SPDK_CEIL_DIV(length, io_unit_size);
1675 
1676 	for (i = 0; i < num_buffers && length > 0; i++) {
1677 		uint32_t buffer_len = spdk_min(length, io_unit_size);
1678 		uint32_t num_sge_in_block = SPDK_CEIL_DIV(buffer_len, block_size);
1679 
1680 		if (num_sge_in_block * block_size > buffer_len) {
1681 			++num_sge_in_block;
1682 		}
1683 		num_sge += num_sge_in_block;
1684 		length -= buffer_len;
1685 	}
1686 	return SPDK_CEIL_DIV(num_sge, SPDK_NVMF_MAX_SGL_ENTRIES);
1687 }
1688 
1689 static int
1690 spdk_nvmf_rdma_request_fill_iovs(struct spdk_nvmf_rdma_transport *rtransport,
1691 				 struct spdk_nvmf_rdma_device *device,
1692 				 struct spdk_nvmf_rdma_request *rdma_req,
1693 				 uint32_t length)
1694 {
1695 	struct spdk_nvmf_rdma_qpair		*rqpair;
1696 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1697 	struct spdk_nvmf_request		*req = &rdma_req->req;
1698 	struct ibv_send_wr			*wr = &rdma_req->data.wr;
1699 	int					rc;
1700 	uint32_t				num_wrs = 1;
1701 
1702 	rqpair = SPDK_CONTAINEROF(req->qpair, struct spdk_nvmf_rdma_qpair, qpair);
1703 	rgroup = rqpair->poller->group;
1704 
1705 	/* rdma wr specifics */
1706 	nvmf_rdma_setup_request(rdma_req);
1707 
1708 	rc = spdk_nvmf_request_get_buffers(req, &rgroup->group, &rtransport->transport,
1709 					   length);
1710 	if (rc != 0) {
1711 		return rc;
1712 	}
1713 
1714 	assert(req->iovcnt <= rqpair->max_send_sge);
1715 
1716 	rdma_req->iovpos = 0;
1717 
1718 	if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1719 		num_wrs = nvmf_rdma_calc_num_wrs(length, rtransport->transport.opts.io_unit_size,
1720 						 req->dif.dif_ctx.block_size);
1721 		if (num_wrs > 1) {
1722 			rc = nvmf_request_alloc_wrs(rtransport, rdma_req, num_wrs - 1);
1723 			if (rc != 0) {
1724 				goto err_exit;
1725 			}
1726 		}
1727 	}
1728 
1729 	rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, wr, length, num_wrs - 1);
1730 	if (spdk_unlikely(rc != 0)) {
1731 		goto err_exit;
1732 	}
1733 
1734 	if (spdk_unlikely(num_wrs > 1)) {
1735 		nvmf_rdma_update_remote_addr(rdma_req, num_wrs);
1736 	}
1737 
1738 	/* set the number of outstanding data WRs for this request. */
1739 	rdma_req->num_outstanding_data_wr = num_wrs;
1740 
1741 	return rc;
1742 
1743 err_exit:
1744 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1745 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1746 	req->iovcnt = 0;
1747 	return rc;
1748 }
1749 
1750 static int
1751 nvmf_rdma_request_fill_iovs_multi_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1752 				      struct spdk_nvmf_rdma_device *device,
1753 				      struct spdk_nvmf_rdma_request *rdma_req)
1754 {
1755 	struct spdk_nvmf_rdma_qpair		*rqpair;
1756 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1757 	struct ibv_send_wr			*current_wr;
1758 	struct spdk_nvmf_request		*req = &rdma_req->req;
1759 	struct spdk_nvme_sgl_descriptor		*inline_segment, *desc;
1760 	uint32_t				num_sgl_descriptors;
1761 	uint32_t				lengths[SPDK_NVMF_MAX_SGL_ENTRIES];
1762 	uint32_t				i;
1763 	int					rc;
1764 
1765 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1766 	rgroup = rqpair->poller->group;
1767 
1768 	inline_segment = &req->cmd->nvme_cmd.dptr.sgl1;
1769 	assert(inline_segment->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT);
1770 	assert(inline_segment->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET);
1771 
1772 	num_sgl_descriptors = inline_segment->unkeyed.length / sizeof(struct spdk_nvme_sgl_descriptor);
1773 	assert(num_sgl_descriptors <= SPDK_NVMF_MAX_SGL_ENTRIES);
1774 
1775 	if (nvmf_request_alloc_wrs(rtransport, rdma_req, num_sgl_descriptors - 1) != 0) {
1776 		return -ENOMEM;
1777 	}
1778 
1779 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1780 	for (i = 0; i < num_sgl_descriptors; i++) {
1781 		if (spdk_likely(!req->dif.dif_insert_or_strip)) {
1782 			lengths[i] = desc->keyed.length;
1783 		} else {
1784 			req->dif.orig_length += desc->keyed.length;
1785 			lengths[i] = spdk_dif_get_length_with_md(desc->keyed.length, &req->dif.dif_ctx);
1786 			req->dif.elba_length += lengths[i];
1787 		}
1788 		desc++;
1789 	}
1790 
1791 	rc = spdk_nvmf_request_get_buffers_multi(req, &rgroup->group, &rtransport->transport,
1792 			lengths, num_sgl_descriptors);
1793 	if (rc != 0) {
1794 		nvmf_rdma_request_free_data(rdma_req, rtransport);
1795 		return rc;
1796 	}
1797 
1798 	/* The first WR must always be the embedded data WR. This is how we unwind them later. */
1799 	current_wr = &rdma_req->data.wr;
1800 	assert(current_wr != NULL);
1801 
1802 	req->length = 0;
1803 	rdma_req->iovpos = 0;
1804 	desc = (struct spdk_nvme_sgl_descriptor *)rdma_req->recv->buf + inline_segment->address;
1805 	for (i = 0; i < num_sgl_descriptors; i++) {
1806 		/* The descriptors must be keyed data block descriptors with an address, not an offset. */
1807 		if (spdk_unlikely(desc->generic.type != SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK ||
1808 				  desc->keyed.subtype != SPDK_NVME_SGL_SUBTYPE_ADDRESS)) {
1809 			rc = -EINVAL;
1810 			goto err_exit;
1811 		}
1812 
1813 		current_wr->num_sge = 0;
1814 
1815 		rc = nvmf_rdma_fill_wr_sgl(rgroup, device, rdma_req, current_wr, lengths[i], 0);
1816 		if (rc != 0) {
1817 			rc = -ENOMEM;
1818 			goto err_exit;
1819 		}
1820 
1821 		req->length += desc->keyed.length;
1822 		current_wr->wr.rdma.rkey = desc->keyed.key;
1823 		current_wr->wr.rdma.remote_addr = desc->address;
1824 		current_wr = current_wr->next;
1825 		desc++;
1826 	}
1827 
1828 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1829 	/* Go back to the last descriptor in the list. */
1830 	desc--;
1831 	if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1832 		if (desc->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1833 			rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1834 			rdma_req->rsp.wr.imm_data = desc->keyed.key;
1835 		}
1836 	}
1837 #endif
1838 
1839 	rdma_req->num_outstanding_data_wr = num_sgl_descriptors;
1840 
1841 	return 0;
1842 
1843 err_exit:
1844 	spdk_nvmf_request_free_buffers(req, &rgroup->group, &rtransport->transport);
1845 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1846 	return rc;
1847 }
1848 
1849 static int
1850 spdk_nvmf_rdma_request_parse_sgl(struct spdk_nvmf_rdma_transport *rtransport,
1851 				 struct spdk_nvmf_rdma_device *device,
1852 				 struct spdk_nvmf_rdma_request *rdma_req)
1853 {
1854 	struct spdk_nvmf_request		*req = &rdma_req->req;
1855 	struct spdk_nvme_cpl			*rsp;
1856 	struct spdk_nvme_sgl_descriptor		*sgl;
1857 	int					rc;
1858 	uint32_t				length;
1859 
1860 	rsp = &req->rsp->nvme_cpl;
1861 	sgl = &req->cmd->nvme_cmd.dptr.sgl1;
1862 
1863 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK &&
1864 	    (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_ADDRESS ||
1865 	     sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY)) {
1866 
1867 		length = sgl->keyed.length;
1868 		if (length > rtransport->transport.opts.max_io_size) {
1869 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1870 				    length, rtransport->transport.opts.max_io_size);
1871 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1872 			return -1;
1873 		}
1874 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
1875 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) != 0) {
1876 			if (sgl->keyed.subtype == SPDK_NVME_SGL_SUBTYPE_INVALIDATE_KEY) {
1877 				rdma_req->rsp.wr.opcode = IBV_WR_SEND_WITH_INV;
1878 				rdma_req->rsp.wr.imm_data = sgl->keyed.key;
1879 			}
1880 		}
1881 #endif
1882 
1883 		/* fill request length and populate iovs */
1884 		req->length = length;
1885 
1886 		if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1887 			req->dif.orig_length = length;
1888 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
1889 			req->dif.elba_length = length;
1890 		}
1891 
1892 		rc = spdk_nvmf_rdma_request_fill_iovs(rtransport, device, rdma_req, length);
1893 		if (spdk_unlikely(rc < 0)) {
1894 			if (rc == -EINVAL) {
1895 				SPDK_ERRLOG("SGL length exceeds the max I/O size\n");
1896 				rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1897 				return -1;
1898 			}
1899 			/* No available buffers. Queue this request up. */
1900 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1901 			return 0;
1902 		}
1903 
1904 		/* backward compatible */
1905 		req->data = req->iov[0].iov_base;
1906 
1907 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1908 			      req->iovcnt);
1909 
1910 		return 0;
1911 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
1912 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1913 		uint64_t offset = sgl->address;
1914 		uint32_t max_len = rtransport->transport.opts.in_capsule_data_size;
1915 
1916 		SPDK_DEBUGLOG(SPDK_LOG_NVMF, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
1917 			      offset, sgl->unkeyed.length);
1918 
1919 		if (offset > max_len) {
1920 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
1921 				    offset, max_len);
1922 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
1923 			return -1;
1924 		}
1925 		max_len -= (uint32_t)offset;
1926 
1927 		if (sgl->unkeyed.length > max_len) {
1928 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
1929 				    sgl->unkeyed.length, max_len);
1930 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1931 			return -1;
1932 		}
1933 
1934 		rdma_req->num_outstanding_data_wr = 0;
1935 		req->data = rdma_req->recv->buf + offset;
1936 		req->data_from_pool = false;
1937 		req->length = sgl->unkeyed.length;
1938 
1939 		req->iov[0].iov_base = req->data;
1940 		req->iov[0].iov_len = req->length;
1941 		req->iovcnt = 1;
1942 
1943 		return 0;
1944 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_LAST_SEGMENT &&
1945 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
1946 
1947 		rc = nvmf_rdma_request_fill_iovs_multi_sgl(rtransport, device, rdma_req);
1948 		if (rc == -ENOMEM) {
1949 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "No available large data buffers. Queueing request %p\n", rdma_req);
1950 			return 0;
1951 		} else if (rc == -EINVAL) {
1952 			SPDK_ERRLOG("Multi SGL element request length exceeds the max I/O size\n");
1953 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1954 			return -1;
1955 		}
1956 
1957 		/* backward compatible */
1958 		req->data = req->iov[0].iov_base;
1959 
1960 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p took %d buffer/s from central pool\n", rdma_req,
1961 			      req->iovcnt);
1962 
1963 		return 0;
1964 	}
1965 
1966 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
1967 		    sgl->generic.type, sgl->generic.subtype);
1968 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
1969 	return -1;
1970 }
1971 
1972 static void
1973 nvmf_rdma_request_free(struct spdk_nvmf_rdma_request *rdma_req,
1974 		       struct spdk_nvmf_rdma_transport	*rtransport)
1975 {
1976 	struct spdk_nvmf_rdma_qpair		*rqpair;
1977 	struct spdk_nvmf_rdma_poll_group	*rgroup;
1978 
1979 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
1980 	if (rdma_req->req.data_from_pool) {
1981 		rgroup = rqpair->poller->group;
1982 
1983 		spdk_nvmf_request_free_buffers(&rdma_req->req, &rgroup->group, &rtransport->transport);
1984 	}
1985 	nvmf_rdma_request_free_data(rdma_req, rtransport);
1986 	rdma_req->req.length = 0;
1987 	rdma_req->req.iovcnt = 0;
1988 	rdma_req->req.data = NULL;
1989 	rdma_req->rsp.wr.next = NULL;
1990 	rdma_req->data.wr.next = NULL;
1991 	memset(&rdma_req->req.dif, 0, sizeof(rdma_req->req.dif));
1992 	rqpair->qd--;
1993 
1994 	STAILQ_INSERT_HEAD(&rqpair->resources->free_queue, rdma_req, state_link);
1995 	rdma_req->state = RDMA_REQUEST_STATE_FREE;
1996 }
1997 
1998 static bool
1999 spdk_nvmf_rdma_request_process(struct spdk_nvmf_rdma_transport *rtransport,
2000 			       struct spdk_nvmf_rdma_request *rdma_req)
2001 {
2002 	struct spdk_nvmf_rdma_qpair	*rqpair;
2003 	struct spdk_nvmf_rdma_device	*device;
2004 	struct spdk_nvmf_rdma_poll_group *rgroup;
2005 	struct spdk_nvme_cpl		*rsp = &rdma_req->req.rsp->nvme_cpl;
2006 	int				rc;
2007 	struct spdk_nvmf_rdma_recv	*rdma_recv;
2008 	enum spdk_nvmf_rdma_request_state prev_state;
2009 	bool				progress = false;
2010 	int				data_posted;
2011 	uint32_t			num_blocks;
2012 
2013 	rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
2014 	device = rqpair->port->device;
2015 	rgroup = rqpair->poller->group;
2016 
2017 	assert(rdma_req->state != RDMA_REQUEST_STATE_FREE);
2018 
2019 	/* If the queue pair is in an error state, force the request to the completed state
2020 	 * to release resources. */
2021 	if (rqpair->ibv_state == IBV_QPS_ERR || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
2022 		if (rdma_req->state == RDMA_REQUEST_STATE_NEED_BUFFER) {
2023 			STAILQ_REMOVE(&rgroup->group.pending_buf_queue, &rdma_req->req, spdk_nvmf_request, buf_link);
2024 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING) {
2025 			STAILQ_REMOVE(&rqpair->pending_rdma_read_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2026 		} else if (rdma_req->state == RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING) {
2027 			STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2028 		}
2029 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2030 	}
2031 
2032 	/* The loop here is to allow for several back-to-back state changes. */
2033 	do {
2034 		prev_state = rdma_req->state;
2035 
2036 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Request %p entering state %d\n", rdma_req, prev_state);
2037 
2038 		switch (rdma_req->state) {
2039 		case RDMA_REQUEST_STATE_FREE:
2040 			/* Some external code must kick a request into RDMA_REQUEST_STATE_NEW
2041 			 * to escape this state. */
2042 			break;
2043 		case RDMA_REQUEST_STATE_NEW:
2044 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEW, 0, 0,
2045 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2046 			rdma_recv = rdma_req->recv;
2047 
2048 			/* The first element of the SGL is the NVMe command */
2049 			rdma_req->req.cmd = (union nvmf_h2c_msg *)rdma_recv->sgl[0].addr;
2050 			memset(rdma_req->req.rsp, 0, sizeof(*rdma_req->req.rsp));
2051 
2052 			if (rqpair->ibv_state == IBV_QPS_ERR  || rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
2053 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2054 				break;
2055 			}
2056 
2057 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&rdma_req->req, &rdma_req->req.dif.dif_ctx))) {
2058 				rdma_req->req.dif.dif_insert_or_strip = true;
2059 			}
2060 
2061 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2062 			rdma_req->rsp.wr.opcode = IBV_WR_SEND;
2063 			rdma_req->rsp.wr.imm_data = 0;
2064 #endif
2065 
2066 			/* The next state transition depends on the data transfer needs of this request. */
2067 			rdma_req->req.xfer = spdk_nvmf_req_get_xfer(&rdma_req->req);
2068 
2069 			/* If no data to transfer, ready to execute. */
2070 			if (rdma_req->req.xfer == SPDK_NVME_DATA_NONE) {
2071 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
2072 				break;
2073 			}
2074 
2075 			rdma_req->state = RDMA_REQUEST_STATE_NEED_BUFFER;
2076 			STAILQ_INSERT_TAIL(&rgroup->group.pending_buf_queue, &rdma_req->req, buf_link);
2077 			break;
2078 		case RDMA_REQUEST_STATE_NEED_BUFFER:
2079 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_NEED_BUFFER, 0, 0,
2080 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2081 
2082 			assert(rdma_req->req.xfer != SPDK_NVME_DATA_NONE);
2083 
2084 			if (&rdma_req->req != STAILQ_FIRST(&rgroup->group.pending_buf_queue)) {
2085 				/* This request needs to wait in line to obtain a buffer */
2086 				break;
2087 			}
2088 
2089 			/* Try to get a data buffer */
2090 			rc = spdk_nvmf_rdma_request_parse_sgl(rtransport, device, rdma_req);
2091 			if (rc < 0) {
2092 				STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2093 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2094 				break;
2095 			}
2096 
2097 			if (!rdma_req->req.data) {
2098 				/* No buffers available. */
2099 				rgroup->stat.pending_data_buffer++;
2100 				break;
2101 			}
2102 
2103 			STAILQ_REMOVE_HEAD(&rgroup->group.pending_buf_queue, buf_link);
2104 
2105 			/* If data is transferring from host to controller and the data didn't
2106 			 * arrive using in capsule data, we need to do a transfer from the host.
2107 			 */
2108 			if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER &&
2109 			    rdma_req->req.data_from_pool) {
2110 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_read_queue, rdma_req, state_link);
2111 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING;
2112 				break;
2113 			}
2114 
2115 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
2116 			break;
2117 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING:
2118 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_CONTROLLER_PENDING, 0, 0,
2119 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2120 
2121 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_read_queue)) {
2122 				/* This request needs to wait in line to perform RDMA */
2123 				break;
2124 			}
2125 			if (rqpair->current_send_depth + rdma_req->num_outstanding_data_wr > rqpair->max_send_depth
2126 			    || rqpair->current_read_depth + rdma_req->num_outstanding_data_wr > rqpair->max_read_depth) {
2127 				/* We can only have so many WRs outstanding. we have to wait until some finish. */
2128 				rqpair->poller->stat.pending_rdma_read++;
2129 				break;
2130 			}
2131 
2132 			/* We have already verified that this request is the head of the queue. */
2133 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_read_queue, state_link);
2134 
2135 			rc = request_transfer_in(&rdma_req->req);
2136 			if (!rc) {
2137 				rdma_req->state = RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER;
2138 			} else {
2139 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
2140 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2141 			}
2142 			break;
2143 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2144 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2145 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2146 			/* Some external code must kick a request into RDMA_REQUEST_STATE_READY_TO_EXECUTE
2147 			 * to escape this state. */
2148 			break;
2149 		case RDMA_REQUEST_STATE_READY_TO_EXECUTE:
2150 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_EXECUTE, 0, 0,
2151 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2152 
2153 			if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
2154 				if (rdma_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2155 					/* generate DIF for write operation */
2156 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2157 					assert(num_blocks > 0);
2158 
2159 					rc = spdk_dif_generate(rdma_req->req.iov, rdma_req->req.iovcnt,
2160 							       num_blocks, &rdma_req->req.dif.dif_ctx);
2161 					if (rc != 0) {
2162 						SPDK_ERRLOG("DIF generation failed\n");
2163 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2164 						spdk_nvmf_rdma_start_disconnect(rqpair);
2165 						break;
2166 					}
2167 				}
2168 
2169 				assert(rdma_req->req.dif.elba_length >= rdma_req->req.length);
2170 				/* set extended length before IO operation */
2171 				rdma_req->req.length = rdma_req->req.dif.elba_length;
2172 			}
2173 
2174 			rdma_req->state = RDMA_REQUEST_STATE_EXECUTING;
2175 			spdk_nvmf_request_exec(&rdma_req->req);
2176 			break;
2177 		case RDMA_REQUEST_STATE_EXECUTING:
2178 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTING, 0, 0,
2179 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2180 			/* Some external code must kick a request into RDMA_REQUEST_STATE_EXECUTED
2181 			 * to escape this state. */
2182 			break;
2183 		case RDMA_REQUEST_STATE_EXECUTED:
2184 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_EXECUTED, 0, 0,
2185 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2186 			if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2187 				STAILQ_INSERT_TAIL(&rqpair->pending_rdma_write_queue, rdma_req, state_link);
2188 				rdma_req->state = RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING;
2189 			} else {
2190 				rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2191 			}
2192 			if (spdk_unlikely(rdma_req->req.dif.dif_insert_or_strip)) {
2193 				/* restore the original length */
2194 				rdma_req->req.length = rdma_req->req.dif.orig_length;
2195 
2196 				if (rdma_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2197 					struct spdk_dif_error error_blk;
2198 
2199 					num_blocks = SPDK_CEIL_DIV(rdma_req->req.dif.elba_length, rdma_req->req.dif.dif_ctx.block_size);
2200 
2201 					rc = spdk_dif_verify(rdma_req->req.iov, rdma_req->req.iovcnt, num_blocks,
2202 							     &rdma_req->req.dif.dif_ctx, &error_blk);
2203 					if (rc) {
2204 						struct spdk_nvme_cpl *rsp = &rdma_req->req.rsp->nvme_cpl;
2205 
2206 						SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n", error_blk.err_type,
2207 							    error_blk.err_offset);
2208 						rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2209 						rsp->status.sc = spdk_nvmf_rdma_dif_error_to_compl_status(error_blk.err_type);
2210 						rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2211 						STAILQ_REMOVE(&rqpair->pending_rdma_write_queue, rdma_req, spdk_nvmf_rdma_request, state_link);
2212 					}
2213 				}
2214 			}
2215 			break;
2216 		case RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING:
2217 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_DATA_TRANSFER_TO_HOST_PENDING, 0, 0,
2218 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2219 
2220 			if (rdma_req != STAILQ_FIRST(&rqpair->pending_rdma_write_queue)) {
2221 				/* This request needs to wait in line to perform RDMA */
2222 				break;
2223 			}
2224 			if ((rqpair->current_send_depth + rdma_req->num_outstanding_data_wr + 1) >
2225 			    rqpair->max_send_depth) {
2226 				/* We can only have so many WRs outstanding. we have to wait until some finish.
2227 				 * +1 since each request has an additional wr in the resp. */
2228 				rqpair->poller->stat.pending_rdma_write++;
2229 				break;
2230 			}
2231 
2232 			/* We have already verified that this request is the head of the queue. */
2233 			STAILQ_REMOVE_HEAD(&rqpair->pending_rdma_write_queue, state_link);
2234 
2235 			/* The data transfer will be kicked off from
2236 			 * RDMA_REQUEST_STATE_READY_TO_COMPLETE state.
2237 			 */
2238 			rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
2239 			break;
2240 		case RDMA_REQUEST_STATE_READY_TO_COMPLETE:
2241 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_READY_TO_COMPLETE, 0, 0,
2242 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2243 			rc = request_transfer_out(&rdma_req->req, &data_posted);
2244 			assert(rc == 0); /* No good way to handle this currently */
2245 			if (rc) {
2246 				rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
2247 			} else {
2248 				rdma_req->state = data_posted ? RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST :
2249 						  RDMA_REQUEST_STATE_COMPLETING;
2250 			}
2251 			break;
2252 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2253 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2254 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2255 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2256 			 * to escape this state. */
2257 			break;
2258 		case RDMA_REQUEST_STATE_COMPLETING:
2259 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETING, 0, 0,
2260 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2261 			/* Some external code must kick a request into RDMA_REQUEST_STATE_COMPLETED
2262 			 * to escape this state. */
2263 			break;
2264 		case RDMA_REQUEST_STATE_COMPLETED:
2265 			spdk_trace_record(TRACE_RDMA_REQUEST_STATE_COMPLETED, 0, 0,
2266 					  (uintptr_t)rdma_req, (uintptr_t)rqpair->cm_id);
2267 
2268 			rqpair->poller->stat.request_latency += spdk_get_ticks() - rdma_req->receive_tsc;
2269 			nvmf_rdma_request_free(rdma_req, rtransport);
2270 			break;
2271 		case RDMA_REQUEST_NUM_STATES:
2272 		default:
2273 			assert(0);
2274 			break;
2275 		}
2276 
2277 		if (rdma_req->state != prev_state) {
2278 			progress = true;
2279 		}
2280 	} while (rdma_req->state != prev_state);
2281 
2282 	return progress;
2283 }
2284 
2285 /* Public API callbacks begin here */
2286 
2287 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH 128
2288 #define SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH 128
2289 #define SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH 4096
2290 #define SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
2291 #define SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2292 #define SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE 131072
2293 #define SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE (SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE / SPDK_NVMF_MAX_SGL_ENTRIES)
2294 #define SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS 4095
2295 #define SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE 32
2296 #define SPDK_NVMF_RDMA_DEFAULT_NO_SRQ false
2297 #define SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP false
2298 
2299 static void
2300 spdk_nvmf_rdma_opts_init(struct spdk_nvmf_transport_opts *opts)
2301 {
2302 	opts->max_queue_depth =		SPDK_NVMF_RDMA_DEFAULT_MAX_QUEUE_DEPTH;
2303 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_RDMA_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2304 	opts->in_capsule_data_size =	SPDK_NVMF_RDMA_DEFAULT_IN_CAPSULE_DATA_SIZE;
2305 	opts->max_io_size =		SPDK_NVMF_RDMA_DEFAULT_MAX_IO_SIZE;
2306 	opts->io_unit_size =		SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE;
2307 	opts->max_aq_depth =		SPDK_NVMF_RDMA_DEFAULT_AQ_DEPTH;
2308 	opts->num_shared_buffers =	SPDK_NVMF_RDMA_DEFAULT_NUM_SHARED_BUFFERS;
2309 	opts->buf_cache_size =		SPDK_NVMF_RDMA_DEFAULT_BUFFER_CACHE_SIZE;
2310 	opts->max_srq_depth =		SPDK_NVMF_RDMA_DEFAULT_SRQ_DEPTH;
2311 	opts->no_srq =			SPDK_NVMF_RDMA_DEFAULT_NO_SRQ;
2312 	opts->dif_insert_or_strip =	SPDK_NVMF_RDMA_DIF_INSERT_OR_STRIP;
2313 }
2314 
2315 const struct spdk_mem_map_ops g_nvmf_rdma_map_ops = {
2316 	.notify_cb = spdk_nvmf_rdma_mem_notify,
2317 	.are_contiguous = spdk_nvmf_rdma_check_contiguous_entries
2318 };
2319 
2320 static int spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport);
2321 
2322 static struct spdk_nvmf_transport *
2323 spdk_nvmf_rdma_create(struct spdk_nvmf_transport_opts *opts)
2324 {
2325 	int rc;
2326 	struct spdk_nvmf_rdma_transport *rtransport;
2327 	struct spdk_nvmf_rdma_device	*device, *tmp;
2328 	struct ibv_context		**contexts;
2329 	uint32_t			i;
2330 	int				flag;
2331 	uint32_t			sge_count;
2332 	uint32_t			min_shared_buffers;
2333 	int				max_device_sge = SPDK_NVMF_MAX_SGL_ENTRIES;
2334 	pthread_mutexattr_t		attr;
2335 
2336 	rtransport = calloc(1, sizeof(*rtransport));
2337 	if (!rtransport) {
2338 		return NULL;
2339 	}
2340 
2341 	if (pthread_mutexattr_init(&attr)) {
2342 		SPDK_ERRLOG("pthread_mutexattr_init() failed\n");
2343 		free(rtransport);
2344 		return NULL;
2345 	}
2346 
2347 	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) {
2348 		SPDK_ERRLOG("pthread_mutexattr_settype() failed\n");
2349 		pthread_mutexattr_destroy(&attr);
2350 		free(rtransport);
2351 		return NULL;
2352 	}
2353 
2354 	if (pthread_mutex_init(&rtransport->lock, &attr)) {
2355 		SPDK_ERRLOG("pthread_mutex_init() failed\n");
2356 		pthread_mutexattr_destroy(&attr);
2357 		free(rtransport);
2358 		return NULL;
2359 	}
2360 
2361 	pthread_mutexattr_destroy(&attr);
2362 
2363 	TAILQ_INIT(&rtransport->devices);
2364 	TAILQ_INIT(&rtransport->ports);
2365 	TAILQ_INIT(&rtransport->poll_groups);
2366 
2367 	rtransport->transport.ops = &spdk_nvmf_transport_rdma;
2368 
2369 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** RDMA Transport Init ***\n"
2370 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
2371 		     "  max_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
2372 		     "  in_capsule_data_size=%d, max_aq_depth=%d,\n"
2373 		     "  num_shared_buffers=%d, max_srq_depth=%d, no_srq=%d\n",
2374 		     opts->max_queue_depth,
2375 		     opts->max_io_size,
2376 		     opts->max_qpairs_per_ctrlr,
2377 		     opts->io_unit_size,
2378 		     opts->in_capsule_data_size,
2379 		     opts->max_aq_depth,
2380 		     opts->num_shared_buffers,
2381 		     opts->max_srq_depth,
2382 		     opts->no_srq);
2383 
2384 	/* I/O unit size cannot be larger than max I/O size */
2385 	if (opts->io_unit_size > opts->max_io_size) {
2386 		opts->io_unit_size = opts->max_io_size;
2387 	}
2388 
2389 	if (opts->num_shared_buffers < (SPDK_NVMF_MAX_SGL_ENTRIES * 2)) {
2390 		SPDK_ERRLOG("The number of shared data buffers (%d) is less than"
2391 			    "the minimum number required to guarantee that forward progress can be made (%d)\n",
2392 			    opts->num_shared_buffers, (SPDK_NVMF_MAX_SGL_ENTRIES * 2));
2393 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2394 		return NULL;
2395 	}
2396 
2397 	min_shared_buffers = spdk_thread_get_count() * opts->buf_cache_size;
2398 	if (min_shared_buffers > opts->num_shared_buffers) {
2399 		SPDK_ERRLOG("There are not enough buffers to satisfy"
2400 			    "per-poll group caches for each thread. (%" PRIu32 ")"
2401 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
2402 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
2403 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2404 		return NULL;
2405 	}
2406 
2407 	sge_count = opts->max_io_size / opts->io_unit_size;
2408 	if (sge_count > NVMF_DEFAULT_TX_SGE) {
2409 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
2410 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2411 		return NULL;
2412 	}
2413 
2414 	rtransport->event_channel = rdma_create_event_channel();
2415 	if (rtransport->event_channel == NULL) {
2416 		SPDK_ERRLOG("rdma_create_event_channel() failed, %s\n", spdk_strerror(errno));
2417 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2418 		return NULL;
2419 	}
2420 
2421 	flag = fcntl(rtransport->event_channel->fd, F_GETFL);
2422 	if (fcntl(rtransport->event_channel->fd, F_SETFL, flag | O_NONBLOCK) < 0) {
2423 		SPDK_ERRLOG("fcntl can't set nonblocking mode for socket, fd: %d (%s)\n",
2424 			    rtransport->event_channel->fd, spdk_strerror(errno));
2425 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2426 		return NULL;
2427 	}
2428 
2429 	rtransport->data_wr_pool = spdk_mempool_create("spdk_nvmf_rdma_wr_data",
2430 				   opts->max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES,
2431 				   sizeof(struct spdk_nvmf_rdma_request_data),
2432 				   SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
2433 				   SPDK_ENV_SOCKET_ID_ANY);
2434 	if (!rtransport->data_wr_pool) {
2435 		SPDK_ERRLOG("Unable to allocate work request pool for poll group\n");
2436 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2437 		return NULL;
2438 	}
2439 
2440 	contexts = rdma_get_devices(NULL);
2441 	if (contexts == NULL) {
2442 		SPDK_ERRLOG("rdma_get_devices() failed: %s (%d)\n", spdk_strerror(errno), errno);
2443 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2444 		return NULL;
2445 	}
2446 
2447 	i = 0;
2448 	rc = 0;
2449 	while (contexts[i] != NULL) {
2450 		device = calloc(1, sizeof(*device));
2451 		if (!device) {
2452 			SPDK_ERRLOG("Unable to allocate memory for RDMA devices.\n");
2453 			rc = -ENOMEM;
2454 			break;
2455 		}
2456 		device->context = contexts[i];
2457 		rc = ibv_query_device(device->context, &device->attr);
2458 		if (rc < 0) {
2459 			SPDK_ERRLOG("Failed to query RDMA device attributes.\n");
2460 			free(device);
2461 			break;
2462 
2463 		}
2464 
2465 		max_device_sge = spdk_min(max_device_sge, device->attr.max_sge);
2466 
2467 #ifdef SPDK_CONFIG_RDMA_SEND_WITH_INVAL
2468 		if ((device->attr.device_cap_flags & IBV_DEVICE_MEM_MGT_EXTENSIONS) == 0) {
2469 			SPDK_WARNLOG("The libibverbs on this system supports SEND_WITH_INVALIDATE,");
2470 			SPDK_WARNLOG("but the device with vendor ID %u does not.\n", device->attr.vendor_id);
2471 		}
2472 
2473 		/**
2474 		 * The vendor ID is assigned by the IEEE and an ID of 0 implies Soft-RoCE.
2475 		 * The Soft-RoCE RXE driver does not currently support send with invalidate,
2476 		 * but incorrectly reports that it does. There are changes making their way
2477 		 * through the kernel now that will enable this feature. When they are merged,
2478 		 * we can conditionally enable this feature.
2479 		 *
2480 		 * TODO: enable this for versions of the kernel rxe driver that support it.
2481 		 */
2482 		if (device->attr.vendor_id == 0) {
2483 			device->attr.device_cap_flags &= ~(IBV_DEVICE_MEM_MGT_EXTENSIONS);
2484 		}
2485 #endif
2486 
2487 		/* set up device context async ev fd as NON_BLOCKING */
2488 		flag = fcntl(device->context->async_fd, F_GETFL);
2489 		rc = fcntl(device->context->async_fd, F_SETFL, flag | O_NONBLOCK);
2490 		if (rc < 0) {
2491 			SPDK_ERRLOG("Failed to set context async fd to NONBLOCK.\n");
2492 			free(device);
2493 			break;
2494 		}
2495 
2496 		TAILQ_INSERT_TAIL(&rtransport->devices, device, link);
2497 		i++;
2498 
2499 		if (g_nvmf_hooks.get_ibv_pd) {
2500 			device->pd = g_nvmf_hooks.get_ibv_pd(NULL, device->context);
2501 		} else {
2502 			device->pd = ibv_alloc_pd(device->context);
2503 		}
2504 
2505 		if (!device->pd) {
2506 			SPDK_ERRLOG("Unable to allocate protection domain.\n");
2507 			rc = -ENOMEM;
2508 			break;
2509 		}
2510 
2511 		assert(device->map == NULL);
2512 
2513 		device->map = spdk_mem_map_alloc(0, &g_nvmf_rdma_map_ops, device->pd);
2514 		if (!device->map) {
2515 			SPDK_ERRLOG("Unable to allocate memory map for listen address\n");
2516 			rc = -ENOMEM;
2517 			break;
2518 		}
2519 
2520 		assert(device->map != NULL);
2521 		assert(device->pd != NULL);
2522 	}
2523 	rdma_free_devices(contexts);
2524 
2525 	if (opts->io_unit_size * max_device_sge < opts->max_io_size) {
2526 		/* divide and round up. */
2527 		opts->io_unit_size = (opts->max_io_size + max_device_sge - 1) / max_device_sge;
2528 
2529 		/* round up to the nearest 4k. */
2530 		opts->io_unit_size = (opts->io_unit_size + NVMF_DATA_BUFFER_ALIGNMENT - 1) & ~NVMF_DATA_BUFFER_MASK;
2531 
2532 		opts->io_unit_size = spdk_max(opts->io_unit_size, SPDK_NVMF_RDMA_MIN_IO_BUFFER_SIZE);
2533 		SPDK_NOTICELOG("Adjusting the io unit size to fit the device's maximum I/O size. New I/O unit size %u\n",
2534 			       opts->io_unit_size);
2535 	}
2536 
2537 	if (rc < 0) {
2538 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2539 		return NULL;
2540 	}
2541 
2542 	/* Set up poll descriptor array to monitor events from RDMA and IB
2543 	 * in a single poll syscall
2544 	 */
2545 	rtransport->npoll_fds = i + 1;
2546 	i = 0;
2547 	rtransport->poll_fds = calloc(rtransport->npoll_fds, sizeof(struct pollfd));
2548 	if (rtransport->poll_fds == NULL) {
2549 		SPDK_ERRLOG("poll_fds allocation failed\n");
2550 		spdk_nvmf_rdma_destroy(&rtransport->transport);
2551 		return NULL;
2552 	}
2553 
2554 	rtransport->poll_fds[i].fd = rtransport->event_channel->fd;
2555 	rtransport->poll_fds[i++].events = POLLIN;
2556 
2557 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
2558 		rtransport->poll_fds[i].fd = device->context->async_fd;
2559 		rtransport->poll_fds[i++].events = POLLIN;
2560 	}
2561 
2562 	return &rtransport->transport;
2563 }
2564 
2565 static int
2566 spdk_nvmf_rdma_destroy(struct spdk_nvmf_transport *transport)
2567 {
2568 	struct spdk_nvmf_rdma_transport	*rtransport;
2569 	struct spdk_nvmf_rdma_port	*port, *port_tmp;
2570 	struct spdk_nvmf_rdma_device	*device, *device_tmp;
2571 
2572 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2573 
2574 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, port_tmp) {
2575 		TAILQ_REMOVE(&rtransport->ports, port, link);
2576 		rdma_destroy_id(port->id);
2577 		free(port);
2578 	}
2579 
2580 	if (rtransport->poll_fds != NULL) {
2581 		free(rtransport->poll_fds);
2582 	}
2583 
2584 	if (rtransport->event_channel != NULL) {
2585 		rdma_destroy_event_channel(rtransport->event_channel);
2586 	}
2587 
2588 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, device_tmp) {
2589 		TAILQ_REMOVE(&rtransport->devices, device, link);
2590 		if (device->map) {
2591 			spdk_mem_map_free(&device->map);
2592 		}
2593 		if (device->pd) {
2594 			if (!g_nvmf_hooks.get_ibv_pd) {
2595 				ibv_dealloc_pd(device->pd);
2596 			}
2597 		}
2598 		free(device);
2599 	}
2600 
2601 	if (rtransport->data_wr_pool != NULL) {
2602 		if (spdk_mempool_count(rtransport->data_wr_pool) !=
2603 		    (transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES)) {
2604 			SPDK_ERRLOG("transport wr pool count is %zu but should be %u\n",
2605 				    spdk_mempool_count(rtransport->data_wr_pool),
2606 				    transport->opts.max_queue_depth * SPDK_NVMF_MAX_SGL_ENTRIES);
2607 		}
2608 	}
2609 
2610 	spdk_mempool_free(rtransport->data_wr_pool);
2611 
2612 	pthread_mutex_destroy(&rtransport->lock);
2613 	free(rtransport);
2614 
2615 	return 0;
2616 }
2617 
2618 static int
2619 spdk_nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
2620 			       struct spdk_nvme_transport_id *trid,
2621 			       bool peer);
2622 
2623 static int
2624 spdk_nvmf_rdma_listen(struct spdk_nvmf_transport *transport,
2625 		      const struct spdk_nvme_transport_id *trid)
2626 {
2627 	struct spdk_nvmf_rdma_transport	*rtransport;
2628 	struct spdk_nvmf_rdma_device	*device;
2629 	struct spdk_nvmf_rdma_port	*port_tmp, *port;
2630 	struct addrinfo			*res;
2631 	struct addrinfo			hints;
2632 	int				family;
2633 	int				rc;
2634 
2635 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2636 
2637 	port = calloc(1, sizeof(*port));
2638 	if (!port) {
2639 		return -ENOMEM;
2640 	}
2641 
2642 	/* Selectively copy the trid. Things like NQN don't matter here - that
2643 	 * mapping is enforced elsewhere.
2644 	 */
2645 	port->trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
2646 	port->trid.adrfam = trid->adrfam;
2647 	snprintf(port->trid.traddr, sizeof(port->trid.traddr), "%s", trid->traddr);
2648 	snprintf(port->trid.trsvcid, sizeof(port->trid.trsvcid), "%s", trid->trsvcid);
2649 
2650 	switch (port->trid.adrfam) {
2651 	case SPDK_NVMF_ADRFAM_IPV4:
2652 		family = AF_INET;
2653 		break;
2654 	case SPDK_NVMF_ADRFAM_IPV6:
2655 		family = AF_INET6;
2656 		break;
2657 	default:
2658 		SPDK_ERRLOG("Unhandled ADRFAM %d\n", port->trid.adrfam);
2659 		free(port);
2660 		return -EINVAL;
2661 	}
2662 
2663 	memset(&hints, 0, sizeof(hints));
2664 	hints.ai_family = family;
2665 	hints.ai_flags = AI_NUMERICSERV;
2666 	hints.ai_socktype = SOCK_STREAM;
2667 	hints.ai_protocol = 0;
2668 
2669 	rc = getaddrinfo(port->trid.traddr, port->trid.trsvcid, &hints, &res);
2670 	if (rc) {
2671 		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(rc), rc);
2672 		free(port);
2673 		return -EINVAL;
2674 	}
2675 
2676 	pthread_mutex_lock(&rtransport->lock);
2677 	assert(rtransport->event_channel != NULL);
2678 	TAILQ_FOREACH(port_tmp, &rtransport->ports, link) {
2679 		if (spdk_nvme_transport_id_compare(&port_tmp->trid, &port->trid) == 0) {
2680 			port_tmp->ref++;
2681 			freeaddrinfo(res);
2682 			free(port);
2683 			/* Already listening at this address */
2684 			pthread_mutex_unlock(&rtransport->lock);
2685 			return 0;
2686 		}
2687 	}
2688 
2689 	rc = rdma_create_id(rtransport->event_channel, &port->id, port, RDMA_PS_TCP);
2690 	if (rc < 0) {
2691 		SPDK_ERRLOG("rdma_create_id() failed\n");
2692 		freeaddrinfo(res);
2693 		free(port);
2694 		pthread_mutex_unlock(&rtransport->lock);
2695 		return rc;
2696 	}
2697 
2698 	rc = rdma_bind_addr(port->id, res->ai_addr);
2699 	freeaddrinfo(res);
2700 
2701 	if (rc < 0) {
2702 		SPDK_ERRLOG("rdma_bind_addr() failed\n");
2703 		rdma_destroy_id(port->id);
2704 		free(port);
2705 		pthread_mutex_unlock(&rtransport->lock);
2706 		return rc;
2707 	}
2708 
2709 	if (!port->id->verbs) {
2710 		SPDK_ERRLOG("ibv_context is null\n");
2711 		rdma_destroy_id(port->id);
2712 		free(port);
2713 		pthread_mutex_unlock(&rtransport->lock);
2714 		return -1;
2715 	}
2716 
2717 	rc = rdma_listen(port->id, 10); /* 10 = backlog */
2718 	if (rc < 0) {
2719 		SPDK_ERRLOG("rdma_listen() failed\n");
2720 		rdma_destroy_id(port->id);
2721 		free(port);
2722 		pthread_mutex_unlock(&rtransport->lock);
2723 		return rc;
2724 	}
2725 
2726 	TAILQ_FOREACH(device, &rtransport->devices, link) {
2727 		if (device->context == port->id->verbs) {
2728 			port->device = device;
2729 			break;
2730 		}
2731 	}
2732 	if (!port->device) {
2733 		SPDK_ERRLOG("Accepted a connection with verbs %p, but unable to find a corresponding device.\n",
2734 			    port->id->verbs);
2735 		rdma_destroy_id(port->id);
2736 		free(port);
2737 		pthread_mutex_unlock(&rtransport->lock);
2738 		return -EINVAL;
2739 	}
2740 
2741 	SPDK_INFOLOG(SPDK_LOG_RDMA, "*** NVMf Target Listening on %s port %d ***\n",
2742 		     port->trid.traddr, ntohs(rdma_get_src_port(port->id)));
2743 
2744 	port->ref = 1;
2745 
2746 	TAILQ_INSERT_TAIL(&rtransport->ports, port, link);
2747 	pthread_mutex_unlock(&rtransport->lock);
2748 
2749 	return 0;
2750 }
2751 
2752 static int
2753 spdk_nvmf_rdma_stop_listen(struct spdk_nvmf_transport *transport,
2754 			   const struct spdk_nvme_transport_id *_trid)
2755 {
2756 	struct spdk_nvmf_rdma_transport *rtransport;
2757 	struct spdk_nvmf_rdma_port *port, *tmp;
2758 	struct spdk_nvme_transport_id trid = {};
2759 
2760 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2761 
2762 	/* Selectively copy the trid. Things like NQN don't matter here - that
2763 	 * mapping is enforced elsewhere.
2764 	 */
2765 	trid.trtype = SPDK_NVME_TRANSPORT_RDMA;
2766 	trid.adrfam = _trid->adrfam;
2767 	snprintf(trid.traddr, sizeof(port->trid.traddr), "%s", _trid->traddr);
2768 	snprintf(trid.trsvcid, sizeof(port->trid.trsvcid), "%s", _trid->trsvcid);
2769 
2770 	pthread_mutex_lock(&rtransport->lock);
2771 	TAILQ_FOREACH_SAFE(port, &rtransport->ports, link, tmp) {
2772 		if (spdk_nvme_transport_id_compare(&port->trid, &trid) == 0) {
2773 			assert(port->ref > 0);
2774 			port->ref--;
2775 			if (port->ref == 0) {
2776 				TAILQ_REMOVE(&rtransport->ports, port, link);
2777 				rdma_destroy_id(port->id);
2778 				free(port);
2779 			}
2780 			break;
2781 		}
2782 	}
2783 
2784 	pthread_mutex_unlock(&rtransport->lock);
2785 	return 0;
2786 }
2787 
2788 static void
2789 spdk_nvmf_rdma_qpair_process_pending(struct spdk_nvmf_rdma_transport *rtransport,
2790 				     struct spdk_nvmf_rdma_qpair *rqpair, bool drain)
2791 {
2792 	struct spdk_nvmf_request *req, *tmp;
2793 	struct spdk_nvmf_rdma_request	*rdma_req, *req_tmp;
2794 	struct spdk_nvmf_rdma_resources *resources;
2795 
2796 	/* We process I/O in the data transfer pending queue at the highest priority. RDMA reads first */
2797 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_read_queue, state_link, req_tmp) {
2798 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2799 			break;
2800 		}
2801 	}
2802 
2803 	/* Then RDMA writes since reads have stronger restrictions than writes */
2804 	STAILQ_FOREACH_SAFE(rdma_req, &rqpair->pending_rdma_write_queue, state_link, req_tmp) {
2805 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2806 			break;
2807 		}
2808 	}
2809 
2810 	/* The second highest priority is I/O waiting on memory buffers. */
2811 	STAILQ_FOREACH_SAFE(req, &rqpair->poller->group->group.pending_buf_queue, buf_link, tmp) {
2812 		rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
2813 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false && drain == false) {
2814 			break;
2815 		}
2816 	}
2817 
2818 	resources = rqpair->resources;
2819 	while (!STAILQ_EMPTY(&resources->free_queue) && !STAILQ_EMPTY(&resources->incoming_queue)) {
2820 		rdma_req = STAILQ_FIRST(&resources->free_queue);
2821 		STAILQ_REMOVE_HEAD(&resources->free_queue, state_link);
2822 		rdma_req->recv = STAILQ_FIRST(&resources->incoming_queue);
2823 		STAILQ_REMOVE_HEAD(&resources->incoming_queue, link);
2824 
2825 		if (rqpair->srq != NULL) {
2826 			rdma_req->req.qpair = &rdma_req->recv->qpair->qpair;
2827 			rdma_req->recv->qpair->qd++;
2828 		} else {
2829 			rqpair->qd++;
2830 		}
2831 
2832 		rdma_req->receive_tsc = rdma_req->recv->receive_tsc;
2833 		rdma_req->state = RDMA_REQUEST_STATE_NEW;
2834 		if (spdk_nvmf_rdma_request_process(rtransport, rdma_req) == false) {
2835 			break;
2836 		}
2837 	}
2838 	if (!STAILQ_EMPTY(&resources->incoming_queue) && STAILQ_EMPTY(&resources->free_queue)) {
2839 		rqpair->poller->stat.pending_free_request++;
2840 	}
2841 }
2842 
2843 static void
2844 _nvmf_rdma_qpair_disconnect(void *ctx)
2845 {
2846 	struct spdk_nvmf_qpair *qpair = ctx;
2847 
2848 	spdk_nvmf_qpair_disconnect(qpair, NULL, NULL);
2849 }
2850 
2851 static void
2852 _nvmf_rdma_try_disconnect(void *ctx)
2853 {
2854 	struct spdk_nvmf_qpair *qpair = ctx;
2855 	struct spdk_nvmf_poll_group *group;
2856 
2857 	/* Read the group out of the qpair. This is normally set and accessed only from
2858 	 * the thread that created the group. Here, we're not on that thread necessarily.
2859 	 * The data member qpair->group begins it's life as NULL and then is assigned to
2860 	 * a pointer and never changes. So fortunately reading this and checking for
2861 	 * non-NULL is thread safe in the x86_64 memory model. */
2862 	group = qpair->group;
2863 
2864 	if (group == NULL) {
2865 		/* The qpair hasn't been assigned to a group yet, so we can't
2866 		 * process a disconnect. Send a message to ourself and try again. */
2867 		spdk_thread_send_msg(spdk_get_thread(), _nvmf_rdma_try_disconnect, qpair);
2868 		return;
2869 	}
2870 
2871 	spdk_thread_send_msg(group->thread, _nvmf_rdma_qpair_disconnect, qpair);
2872 }
2873 
2874 static inline void
2875 spdk_nvmf_rdma_start_disconnect(struct spdk_nvmf_rdma_qpair *rqpair)
2876 {
2877 	if (!__atomic_test_and_set(&rqpair->disconnect_started, __ATOMIC_RELAXED)) {
2878 		_nvmf_rdma_try_disconnect(&rqpair->qpair);
2879 	}
2880 }
2881 
2882 static void nvmf_rdma_destroy_drained_qpair(void *ctx)
2883 {
2884 	struct spdk_nvmf_rdma_qpair *rqpair = ctx;
2885 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
2886 			struct spdk_nvmf_rdma_transport, transport);
2887 
2888 	/* In non SRQ path, we will reach rqpair->max_queue_depth. In SRQ path, we will get the last_wqe event. */
2889 	if (rqpair->current_send_depth != 0) {
2890 		return;
2891 	}
2892 
2893 	if (rqpair->srq == NULL && rqpair->current_recv_depth != rqpair->max_queue_depth) {
2894 		return;
2895 	}
2896 
2897 	if (rqpair->srq != NULL && rqpair->last_wqe_reached == false) {
2898 		return;
2899 	}
2900 
2901 	spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
2902 
2903 	/* Qpair will be destroyed after nvmf layer closes this qpair */
2904 	if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ERROR) {
2905 		return;
2906 	}
2907 
2908 	spdk_nvmf_rdma_qpair_destroy(rqpair);
2909 }
2910 
2911 
2912 static int
2913 nvmf_rdma_disconnect(struct rdma_cm_event *evt)
2914 {
2915 	struct spdk_nvmf_qpair		*qpair;
2916 	struct spdk_nvmf_rdma_qpair	*rqpair;
2917 
2918 	if (evt->id == NULL) {
2919 		SPDK_ERRLOG("disconnect request: missing cm_id\n");
2920 		return -1;
2921 	}
2922 
2923 	qpair = evt->id->context;
2924 	if (qpair == NULL) {
2925 		SPDK_ERRLOG("disconnect request: no active connection\n");
2926 		return -1;
2927 	}
2928 
2929 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
2930 
2931 	spdk_trace_record(TRACE_RDMA_QP_DISCONNECT, 0, 0, (uintptr_t)rqpair->cm_id, 0);
2932 
2933 	spdk_nvmf_rdma_start_disconnect(rqpair);
2934 
2935 	return 0;
2936 }
2937 
2938 #ifdef DEBUG
2939 static const char *CM_EVENT_STR[] = {
2940 	"RDMA_CM_EVENT_ADDR_RESOLVED",
2941 	"RDMA_CM_EVENT_ADDR_ERROR",
2942 	"RDMA_CM_EVENT_ROUTE_RESOLVED",
2943 	"RDMA_CM_EVENT_ROUTE_ERROR",
2944 	"RDMA_CM_EVENT_CONNECT_REQUEST",
2945 	"RDMA_CM_EVENT_CONNECT_RESPONSE",
2946 	"RDMA_CM_EVENT_CONNECT_ERROR",
2947 	"RDMA_CM_EVENT_UNREACHABLE",
2948 	"RDMA_CM_EVENT_REJECTED",
2949 	"RDMA_CM_EVENT_ESTABLISHED",
2950 	"RDMA_CM_EVENT_DISCONNECTED",
2951 	"RDMA_CM_EVENT_DEVICE_REMOVAL",
2952 	"RDMA_CM_EVENT_MULTICAST_JOIN",
2953 	"RDMA_CM_EVENT_MULTICAST_ERROR",
2954 	"RDMA_CM_EVENT_ADDR_CHANGE",
2955 	"RDMA_CM_EVENT_TIMEWAIT_EXIT"
2956 };
2957 #endif /* DEBUG */
2958 
2959 static void
2960 spdk_nvmf_process_cm_event(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn, void *cb_arg)
2961 {
2962 	struct spdk_nvmf_rdma_transport *rtransport;
2963 	struct rdma_cm_event		*event;
2964 	int				rc;
2965 
2966 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
2967 
2968 	if (rtransport->event_channel == NULL) {
2969 		return;
2970 	}
2971 
2972 	while (1) {
2973 		rc = rdma_get_cm_event(rtransport->event_channel, &event);
2974 		if (rc == 0) {
2975 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Acceptor Event: %s\n", CM_EVENT_STR[event->event]);
2976 
2977 			spdk_trace_record(TRACE_RDMA_CM_ASYNC_EVENT, 0, 0, 0, event->event);
2978 
2979 			switch (event->event) {
2980 			case RDMA_CM_EVENT_ADDR_RESOLVED:
2981 			case RDMA_CM_EVENT_ADDR_ERROR:
2982 			case RDMA_CM_EVENT_ROUTE_RESOLVED:
2983 			case RDMA_CM_EVENT_ROUTE_ERROR:
2984 				/* No action required. The target never attempts to resolve routes. */
2985 				break;
2986 			case RDMA_CM_EVENT_CONNECT_REQUEST:
2987 				rc = nvmf_rdma_connect(transport, event, cb_fn, cb_arg);
2988 				if (rc < 0) {
2989 					SPDK_ERRLOG("Unable to process connect event. rc: %d\n", rc);
2990 					break;
2991 				}
2992 				break;
2993 			case RDMA_CM_EVENT_CONNECT_RESPONSE:
2994 				/* The target never initiates a new connection. So this will not occur. */
2995 				break;
2996 			case RDMA_CM_EVENT_CONNECT_ERROR:
2997 				/* Can this happen? The docs say it can, but not sure what causes it. */
2998 				break;
2999 			case RDMA_CM_EVENT_UNREACHABLE:
3000 			case RDMA_CM_EVENT_REJECTED:
3001 				/* These only occur on the client side. */
3002 				break;
3003 			case RDMA_CM_EVENT_ESTABLISHED:
3004 				/* TODO: Should we be waiting for this event anywhere? */
3005 				break;
3006 			case RDMA_CM_EVENT_DISCONNECTED:
3007 			case RDMA_CM_EVENT_DEVICE_REMOVAL:
3008 				rc = nvmf_rdma_disconnect(event);
3009 				if (rc < 0) {
3010 					SPDK_ERRLOG("Unable to process disconnect event. rc: %d\n", rc);
3011 					break;
3012 				}
3013 				break;
3014 			case RDMA_CM_EVENT_MULTICAST_JOIN:
3015 			case RDMA_CM_EVENT_MULTICAST_ERROR:
3016 				/* Multicast is not used */
3017 				break;
3018 			case RDMA_CM_EVENT_ADDR_CHANGE:
3019 				/* Not utilizing this event */
3020 				break;
3021 			case RDMA_CM_EVENT_TIMEWAIT_EXIT:
3022 				/* For now, do nothing. The target never re-uses queue pairs. */
3023 				break;
3024 			default:
3025 				SPDK_ERRLOG("Unexpected Acceptor Event [%d]\n", event->event);
3026 				break;
3027 			}
3028 
3029 			rdma_ack_cm_event(event);
3030 		} else {
3031 			if (errno != EAGAIN && errno != EWOULDBLOCK) {
3032 				SPDK_ERRLOG("Acceptor Event Error: %s\n", spdk_strerror(errno));
3033 			}
3034 			break;
3035 		}
3036 	}
3037 }
3038 
3039 static void
3040 nvmf_rdma_handle_qp_fatal(struct spdk_nvmf_rdma_qpair *rqpair)
3041 {
3042 	spdk_nvmf_rdma_update_ibv_state(rqpair);
3043 	spdk_nvmf_rdma_start_disconnect(rqpair);
3044 }
3045 
3046 static void
3047 nvmf_rdma_handle_last_wqe_reached(struct spdk_nvmf_rdma_qpair *rqpair)
3048 {
3049 	rqpair->last_wqe_reached = true;
3050 	nvmf_rdma_destroy_drained_qpair(rqpair);
3051 }
3052 
3053 static void
3054 nvmf_rdma_handle_sq_drained(struct spdk_nvmf_rdma_qpair *rqpair)
3055 {
3056 	spdk_nvmf_rdma_start_disconnect(rqpair);
3057 }
3058 
3059 static void
3060 spdk_nvmf_rdma_qpair_process_ibv_event(void *ctx)
3061 {
3062 	struct spdk_nvmf_rdma_ibv_event_ctx *event_ctx = ctx;
3063 
3064 	if (event_ctx->rqpair) {
3065 		STAILQ_REMOVE(&event_ctx->rqpair->ibv_events, event_ctx, spdk_nvmf_rdma_ibv_event_ctx, link);
3066 		if (event_ctx->cb_fn) {
3067 			event_ctx->cb_fn(event_ctx->rqpair);
3068 		}
3069 	}
3070 	free(event_ctx);
3071 }
3072 
3073 static int
3074 spdk_nvmf_rdma_send_qpair_async_event(struct spdk_nvmf_rdma_qpair *rqpair,
3075 				      spdk_nvmf_rdma_qpair_ibv_event fn)
3076 {
3077 	struct spdk_nvmf_rdma_ibv_event_ctx *ctx;
3078 
3079 	if (!rqpair->qpair.group) {
3080 		return EINVAL;
3081 	}
3082 
3083 	ctx = calloc(1, sizeof(*ctx));
3084 	if (!ctx) {
3085 		return ENOMEM;
3086 	}
3087 
3088 	ctx->rqpair = rqpair;
3089 	ctx->cb_fn = fn;
3090 	STAILQ_INSERT_TAIL(&rqpair->ibv_events, ctx, link);
3091 
3092 	return spdk_thread_send_msg(rqpair->qpair.group->thread, spdk_nvmf_rdma_qpair_process_ibv_event,
3093 				    ctx);
3094 }
3095 
3096 static void
3097 spdk_nvmf_process_ib_event(struct spdk_nvmf_rdma_device *device)
3098 {
3099 	int				rc;
3100 	struct spdk_nvmf_rdma_qpair	*rqpair = NULL;
3101 	struct ibv_async_event		event;
3102 
3103 	rc = ibv_get_async_event(device->context, &event);
3104 
3105 	if (rc) {
3106 		SPDK_ERRLOG("Failed to get async_event (%d): %s\n",
3107 			    errno, spdk_strerror(errno));
3108 		return;
3109 	}
3110 
3111 	switch (event.event_type) {
3112 	case IBV_EVENT_QP_FATAL:
3113 		rqpair = event.element.qp->qp_context;
3114 		SPDK_ERRLOG("Fatal event received for rqpair %p\n", rqpair);
3115 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3116 				  (uintptr_t)rqpair->cm_id, event.event_type);
3117 		if (spdk_nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_qp_fatal)) {
3118 			SPDK_ERRLOG("Failed to send QP_FATAL event for rqpair %p\n", rqpair);
3119 			nvmf_rdma_handle_qp_fatal(rqpair);
3120 		}
3121 		break;
3122 	case IBV_EVENT_QP_LAST_WQE_REACHED:
3123 		/* This event only occurs for shared receive queues. */
3124 		rqpair = event.element.qp->qp_context;
3125 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Last WQE reached event received for rqpair %p\n", rqpair);
3126 		if (spdk_nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_last_wqe_reached)) {
3127 			SPDK_ERRLOG("Failed to send LAST_WQE_REACHED event for rqpair %p\n", rqpair);
3128 			rqpair->last_wqe_reached = true;
3129 		}
3130 		break;
3131 	case IBV_EVENT_SQ_DRAINED:
3132 		/* This event occurs frequently in both error and non-error states.
3133 		 * Check if the qpair is in an error state before sending a message. */
3134 		rqpair = event.element.qp->qp_context;
3135 		SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Last sq drained event received for rqpair %p\n", rqpair);
3136 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3137 				  (uintptr_t)rqpair->cm_id, event.event_type);
3138 		if (spdk_nvmf_rdma_update_ibv_state(rqpair) == IBV_QPS_ERR) {
3139 			if (spdk_nvmf_rdma_send_qpair_async_event(rqpair, nvmf_rdma_handle_sq_drained)) {
3140 				SPDK_ERRLOG("Failed to send SQ_DRAINED event for rqpair %p\n", rqpair);
3141 				nvmf_rdma_handle_sq_drained(rqpair);
3142 			}
3143 		}
3144 		break;
3145 	case IBV_EVENT_QP_REQ_ERR:
3146 	case IBV_EVENT_QP_ACCESS_ERR:
3147 	case IBV_EVENT_COMM_EST:
3148 	case IBV_EVENT_PATH_MIG:
3149 	case IBV_EVENT_PATH_MIG_ERR:
3150 		SPDK_NOTICELOG("Async event: %s\n",
3151 			       ibv_event_type_str(event.event_type));
3152 		rqpair = event.element.qp->qp_context;
3153 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0,
3154 				  (uintptr_t)rqpair->cm_id, event.event_type);
3155 		spdk_nvmf_rdma_update_ibv_state(rqpair);
3156 		break;
3157 	case IBV_EVENT_CQ_ERR:
3158 	case IBV_EVENT_DEVICE_FATAL:
3159 	case IBV_EVENT_PORT_ACTIVE:
3160 	case IBV_EVENT_PORT_ERR:
3161 	case IBV_EVENT_LID_CHANGE:
3162 	case IBV_EVENT_PKEY_CHANGE:
3163 	case IBV_EVENT_SM_CHANGE:
3164 	case IBV_EVENT_SRQ_ERR:
3165 	case IBV_EVENT_SRQ_LIMIT_REACHED:
3166 	case IBV_EVENT_CLIENT_REREGISTER:
3167 	case IBV_EVENT_GID_CHANGE:
3168 	default:
3169 		SPDK_NOTICELOG("Async event: %s\n",
3170 			       ibv_event_type_str(event.event_type));
3171 		spdk_trace_record(TRACE_RDMA_IBV_ASYNC_EVENT, 0, 0, 0, event.event_type);
3172 		break;
3173 	}
3174 	ibv_ack_async_event(&event);
3175 }
3176 
3177 static void
3178 spdk_nvmf_rdma_accept(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn, void *cb_arg)
3179 {
3180 	int	nfds, i = 0;
3181 	struct spdk_nvmf_rdma_transport *rtransport;
3182 	struct spdk_nvmf_rdma_device *device, *tmp;
3183 
3184 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3185 	nfds = poll(rtransport->poll_fds, rtransport->npoll_fds, 0);
3186 
3187 	if (nfds <= 0) {
3188 		return;
3189 	}
3190 
3191 	/* The first poll descriptor is RDMA CM event */
3192 	if (rtransport->poll_fds[i++].revents & POLLIN) {
3193 		spdk_nvmf_process_cm_event(transport, cb_fn, cb_arg);
3194 		nfds--;
3195 	}
3196 
3197 	if (nfds == 0) {
3198 		return;
3199 	}
3200 
3201 	/* Second and subsequent poll descriptors are IB async events */
3202 	TAILQ_FOREACH_SAFE(device, &rtransport->devices, link, tmp) {
3203 		if (rtransport->poll_fds[i++].revents & POLLIN) {
3204 			spdk_nvmf_process_ib_event(device);
3205 			nfds--;
3206 		}
3207 	}
3208 	/* check all flagged fd's have been served */
3209 	assert(nfds == 0);
3210 }
3211 
3212 static void
3213 spdk_nvmf_rdma_discover(struct spdk_nvmf_transport *transport,
3214 			struct spdk_nvme_transport_id *trid,
3215 			struct spdk_nvmf_discovery_log_page_entry *entry)
3216 {
3217 	entry->trtype = SPDK_NVMF_TRTYPE_RDMA;
3218 	entry->adrfam = trid->adrfam;
3219 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
3220 
3221 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
3222 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
3223 
3224 	entry->tsas.rdma.rdma_qptype = SPDK_NVMF_RDMA_QPTYPE_RELIABLE_CONNECTED;
3225 	entry->tsas.rdma.rdma_prtype = SPDK_NVMF_RDMA_PRTYPE_NONE;
3226 	entry->tsas.rdma.rdma_cms = SPDK_NVMF_RDMA_CMS_RDMA_CM;
3227 }
3228 
3229 static void
3230 spdk_nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
3231 
3232 static struct spdk_nvmf_transport_poll_group *
3233 spdk_nvmf_rdma_poll_group_create(struct spdk_nvmf_transport *transport)
3234 {
3235 	struct spdk_nvmf_rdma_transport		*rtransport;
3236 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3237 	struct spdk_nvmf_rdma_poller		*poller;
3238 	struct spdk_nvmf_rdma_device		*device;
3239 	struct ibv_srq_init_attr		srq_init_attr;
3240 	struct spdk_nvmf_rdma_resource_opts	opts;
3241 	int					num_cqe;
3242 
3243 	rtransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_rdma_transport, transport);
3244 
3245 	rgroup = calloc(1, sizeof(*rgroup));
3246 	if (!rgroup) {
3247 		return NULL;
3248 	}
3249 
3250 	TAILQ_INIT(&rgroup->pollers);
3251 	STAILQ_INIT(&rgroup->retired_bufs);
3252 
3253 	pthread_mutex_lock(&rtransport->lock);
3254 	TAILQ_FOREACH(device, &rtransport->devices, link) {
3255 		poller = calloc(1, sizeof(*poller));
3256 		if (!poller) {
3257 			SPDK_ERRLOG("Unable to allocate memory for new RDMA poller\n");
3258 			spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
3259 			pthread_mutex_unlock(&rtransport->lock);
3260 			return NULL;
3261 		}
3262 
3263 		poller->device = device;
3264 		poller->group = rgroup;
3265 
3266 		TAILQ_INIT(&poller->qpairs);
3267 		STAILQ_INIT(&poller->qpairs_pending_send);
3268 		STAILQ_INIT(&poller->qpairs_pending_recv);
3269 
3270 		TAILQ_INSERT_TAIL(&rgroup->pollers, poller, link);
3271 		if (transport->opts.no_srq == false && device->num_srq < device->attr.max_srq) {
3272 			poller->max_srq_depth = transport->opts.max_srq_depth;
3273 
3274 			device->num_srq++;
3275 			memset(&srq_init_attr, 0, sizeof(struct ibv_srq_init_attr));
3276 			srq_init_attr.attr.max_wr = poller->max_srq_depth;
3277 			srq_init_attr.attr.max_sge = spdk_min(device->attr.max_sge, NVMF_DEFAULT_RX_SGE);
3278 			poller->srq = ibv_create_srq(device->pd, &srq_init_attr);
3279 			if (!poller->srq) {
3280 				SPDK_ERRLOG("Unable to create shared receive queue, errno %d\n", errno);
3281 				spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
3282 				pthread_mutex_unlock(&rtransport->lock);
3283 				return NULL;
3284 			}
3285 
3286 			opts.qp = poller->srq;
3287 			opts.pd = device->pd;
3288 			opts.qpair = NULL;
3289 			opts.shared = true;
3290 			opts.max_queue_depth = poller->max_srq_depth;
3291 			opts.in_capsule_data_size = transport->opts.in_capsule_data_size;
3292 
3293 			poller->resources = nvmf_rdma_resources_create(&opts);
3294 			if (!poller->resources) {
3295 				SPDK_ERRLOG("Unable to allocate resources for shared receive queue.\n");
3296 				spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
3297 				pthread_mutex_unlock(&rtransport->lock);
3298 				return NULL;
3299 			}
3300 		}
3301 
3302 		/*
3303 		 * When using an srq, we can limit the completion queue at startup.
3304 		 * The following formula represents the calculation:
3305 		 * num_cqe = num_recv + num_data_wr + num_send_wr.
3306 		 * where num_recv=num_data_wr=and num_send_wr=poller->max_srq_depth
3307 		 */
3308 		if (poller->srq) {
3309 			num_cqe = poller->max_srq_depth * 3;
3310 		} else {
3311 			num_cqe = DEFAULT_NVMF_RDMA_CQ_SIZE;
3312 		}
3313 
3314 		poller->cq = ibv_create_cq(device->context, num_cqe, poller, NULL, 0);
3315 		if (!poller->cq) {
3316 			SPDK_ERRLOG("Unable to create completion queue\n");
3317 			spdk_nvmf_rdma_poll_group_destroy(&rgroup->group);
3318 			pthread_mutex_unlock(&rtransport->lock);
3319 			return NULL;
3320 		}
3321 		poller->num_cqe = num_cqe;
3322 	}
3323 
3324 	TAILQ_INSERT_TAIL(&rtransport->poll_groups, rgroup, link);
3325 	if (rtransport->conn_sched.next_admin_pg == NULL) {
3326 		rtransport->conn_sched.next_admin_pg = rgroup;
3327 		rtransport->conn_sched.next_io_pg = rgroup;
3328 	}
3329 
3330 	pthread_mutex_unlock(&rtransport->lock);
3331 	return &rgroup->group;
3332 }
3333 
3334 static struct spdk_nvmf_transport_poll_group *
3335 spdk_nvmf_rdma_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
3336 {
3337 	struct spdk_nvmf_rdma_transport *rtransport;
3338 	struct spdk_nvmf_rdma_poll_group **pg;
3339 	struct spdk_nvmf_transport_poll_group *result;
3340 
3341 	rtransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_rdma_transport, transport);
3342 
3343 	pthread_mutex_lock(&rtransport->lock);
3344 
3345 	if (TAILQ_EMPTY(&rtransport->poll_groups)) {
3346 		pthread_mutex_unlock(&rtransport->lock);
3347 		return NULL;
3348 	}
3349 
3350 	if (qpair->qid == 0) {
3351 		pg = &rtransport->conn_sched.next_admin_pg;
3352 	} else {
3353 		pg = &rtransport->conn_sched.next_io_pg;
3354 	}
3355 
3356 	assert(*pg != NULL);
3357 
3358 	result = &(*pg)->group;
3359 
3360 	*pg = TAILQ_NEXT(*pg, link);
3361 	if (*pg == NULL) {
3362 		*pg = TAILQ_FIRST(&rtransport->poll_groups);
3363 	}
3364 
3365 	pthread_mutex_unlock(&rtransport->lock);
3366 
3367 	return result;
3368 }
3369 
3370 static void
3371 spdk_nvmf_rdma_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
3372 {
3373 	struct spdk_nvmf_rdma_poll_group	*rgroup, *next_rgroup;
3374 	struct spdk_nvmf_rdma_poller		*poller, *tmp;
3375 	struct spdk_nvmf_rdma_qpair		*qpair, *tmp_qpair;
3376 	struct spdk_nvmf_transport_pg_cache_buf	*buf, *tmp_buf;
3377 	struct spdk_nvmf_rdma_transport		*rtransport;
3378 
3379 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3380 	if (!rgroup) {
3381 		return;
3382 	}
3383 
3384 	/* free all retired buffers back to the transport so we don't short the mempool. */
3385 	STAILQ_FOREACH_SAFE(buf, &rgroup->retired_bufs, link, tmp_buf) {
3386 		STAILQ_REMOVE(&rgroup->retired_bufs, buf, spdk_nvmf_transport_pg_cache_buf, link);
3387 		assert(group->transport != NULL);
3388 		spdk_mempool_put(group->transport->data_buf_pool, buf);
3389 	}
3390 
3391 	TAILQ_FOREACH_SAFE(poller, &rgroup->pollers, link, tmp) {
3392 		TAILQ_REMOVE(&rgroup->pollers, poller, link);
3393 
3394 		TAILQ_FOREACH_SAFE(qpair, &poller->qpairs, link, tmp_qpair) {
3395 			spdk_nvmf_rdma_qpair_destroy(qpair);
3396 		}
3397 
3398 		if (poller->srq) {
3399 			nvmf_rdma_resources_destroy(poller->resources);
3400 			ibv_destroy_srq(poller->srq);
3401 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "Destroyed RDMA shared queue %p\n", poller->srq);
3402 		}
3403 
3404 		if (poller->cq) {
3405 			ibv_destroy_cq(poller->cq);
3406 		}
3407 
3408 		free(poller);
3409 	}
3410 
3411 	if (rgroup->group.transport == NULL) {
3412 		/* Transport can be NULL when spdk_nvmf_rdma_poll_group_create()
3413 		 * calls this function directly in a failure path. */
3414 		free(rgroup);
3415 		return;
3416 	}
3417 
3418 	rtransport = SPDK_CONTAINEROF(rgroup->group.transport, struct spdk_nvmf_rdma_transport, transport);
3419 
3420 	pthread_mutex_lock(&rtransport->lock);
3421 	next_rgroup = TAILQ_NEXT(rgroup, link);
3422 	TAILQ_REMOVE(&rtransport->poll_groups, rgroup, link);
3423 	if (next_rgroup == NULL) {
3424 		next_rgroup = TAILQ_FIRST(&rtransport->poll_groups);
3425 	}
3426 	if (rtransport->conn_sched.next_admin_pg == rgroup) {
3427 		rtransport->conn_sched.next_admin_pg = next_rgroup;
3428 	}
3429 	if (rtransport->conn_sched.next_io_pg == rgroup) {
3430 		rtransport->conn_sched.next_io_pg = next_rgroup;
3431 	}
3432 	pthread_mutex_unlock(&rtransport->lock);
3433 
3434 	free(rgroup);
3435 }
3436 
3437 static void
3438 spdk_nvmf_rdma_qpair_reject_connection(struct spdk_nvmf_rdma_qpair *rqpair)
3439 {
3440 	if (rqpair->cm_id != NULL) {
3441 		spdk_nvmf_rdma_event_reject(rqpair->cm_id, SPDK_NVMF_RDMA_ERROR_NO_RESOURCES);
3442 	}
3443 	spdk_nvmf_rdma_qpair_destroy(rqpair);
3444 }
3445 
3446 static int
3447 spdk_nvmf_rdma_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
3448 			      struct spdk_nvmf_qpair *qpair)
3449 {
3450 	struct spdk_nvmf_rdma_poll_group	*rgroup;
3451 	struct spdk_nvmf_rdma_qpair		*rqpair;
3452 	struct spdk_nvmf_rdma_device		*device;
3453 	struct spdk_nvmf_rdma_poller		*poller;
3454 	int					rc;
3455 
3456 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3457 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3458 
3459 	device = rqpair->port->device;
3460 
3461 	TAILQ_FOREACH(poller, &rgroup->pollers, link) {
3462 		if (poller->device == device) {
3463 			break;
3464 		}
3465 	}
3466 
3467 	if (!poller) {
3468 		SPDK_ERRLOG("No poller found for device.\n");
3469 		return -1;
3470 	}
3471 
3472 	TAILQ_INSERT_TAIL(&poller->qpairs, rqpair, link);
3473 	rqpair->poller = poller;
3474 	rqpair->srq = rqpair->poller->srq;
3475 
3476 	rc = spdk_nvmf_rdma_qpair_initialize(qpair);
3477 	if (rc < 0) {
3478 		SPDK_ERRLOG("Failed to initialize nvmf_rdma_qpair with qpair=%p\n", qpair);
3479 		return -1;
3480 	}
3481 
3482 	rc = spdk_nvmf_rdma_event_accept(rqpair->cm_id, rqpair);
3483 	if (rc) {
3484 		/* Try to reject, but we probably can't */
3485 		spdk_nvmf_rdma_qpair_reject_connection(rqpair);
3486 		return -1;
3487 	}
3488 
3489 	spdk_nvmf_rdma_update_ibv_state(rqpair);
3490 
3491 	return 0;
3492 }
3493 
3494 static int
3495 spdk_nvmf_rdma_request_free(struct spdk_nvmf_request *req)
3496 {
3497 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_rdma_request, req);
3498 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3499 			struct spdk_nvmf_rdma_transport, transport);
3500 
3501 	nvmf_rdma_request_free(rdma_req, rtransport);
3502 	return 0;
3503 }
3504 
3505 static int
3506 spdk_nvmf_rdma_request_complete(struct spdk_nvmf_request *req)
3507 {
3508 	struct spdk_nvmf_rdma_transport	*rtransport = SPDK_CONTAINEROF(req->qpair->transport,
3509 			struct spdk_nvmf_rdma_transport, transport);
3510 	struct spdk_nvmf_rdma_request	*rdma_req = SPDK_CONTAINEROF(req,
3511 			struct spdk_nvmf_rdma_request, req);
3512 	struct spdk_nvmf_rdma_qpair     *rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair,
3513 			struct spdk_nvmf_rdma_qpair, qpair);
3514 
3515 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3516 		/* The connection is alive, so process the request as normal */
3517 		rdma_req->state = RDMA_REQUEST_STATE_EXECUTED;
3518 	} else {
3519 		/* The connection is dead. Move the request directly to the completed state. */
3520 		rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3521 	}
3522 
3523 	spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3524 
3525 	return 0;
3526 }
3527 
3528 static int
3529 spdk_nvmf_rdma_destroy_defunct_qpair(void *ctx)
3530 {
3531 	struct spdk_nvmf_rdma_qpair	*rqpair = ctx;
3532 	struct spdk_nvmf_rdma_transport *rtransport = SPDK_CONTAINEROF(rqpair->qpair.transport,
3533 			struct spdk_nvmf_rdma_transport, transport);
3534 
3535 	SPDK_INFOLOG(SPDK_LOG_RDMA, "QP#%d hasn't been drained as expected, manually destroy it\n",
3536 		     rqpair->qpair.qid);
3537 
3538 	spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, true);
3539 	spdk_nvmf_rdma_qpair_destroy(rqpair);
3540 
3541 	return 0;
3542 }
3543 
3544 static void
3545 spdk_nvmf_rdma_close_qpair(struct spdk_nvmf_qpair *qpair)
3546 {
3547 	struct spdk_nvmf_rdma_qpair *rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3548 
3549 	if (rqpair->disconnect_flags & RDMA_QP_DISCONNECTING) {
3550 		return;
3551 	}
3552 
3553 	rqpair->disconnect_flags |= RDMA_QP_DISCONNECTING;
3554 
3555 	/* This happens only when the qpair is disconnected before
3556 	 * it is added to the poll group. Since there is no poll group,
3557 	 * the RDMA qp has not been initialized yet and the RDMA CM
3558 	 * event has not yet been acknowledged, so we need to reject it.
3559 	 */
3560 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_UNINITIALIZED) {
3561 		spdk_nvmf_rdma_qpair_reject_connection(rqpair);
3562 		return;
3563 	}
3564 
3565 	if (rqpair->ibv_state != IBV_QPS_ERR) {
3566 		spdk_nvmf_rdma_set_ibv_state(rqpair, IBV_QPS_ERR);
3567 	}
3568 
3569 	rqpair->destruct_poller = spdk_poller_register(spdk_nvmf_rdma_destroy_defunct_qpair, (void *)rqpair,
3570 				  NVMF_RDMA_QPAIR_DESTROY_TIMEOUT_US);
3571 }
3572 
3573 static struct spdk_nvmf_rdma_qpair *
3574 get_rdma_qpair_from_wc(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_wc *wc)
3575 {
3576 	struct spdk_nvmf_rdma_qpair *rqpair;
3577 	/* @todo: improve QP search */
3578 	TAILQ_FOREACH(rqpair, &rpoller->qpairs, link) {
3579 		if (wc->qp_num == rqpair->cm_id->qp->qp_num) {
3580 			return rqpair;
3581 		}
3582 	}
3583 	SPDK_ERRLOG("Didn't find QP with qp_num %u\n", wc->qp_num);
3584 	return NULL;
3585 }
3586 
3587 #ifdef DEBUG
3588 static int
3589 spdk_nvmf_rdma_req_is_completing(struct spdk_nvmf_rdma_request *rdma_req)
3590 {
3591 	return rdma_req->state == RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST ||
3592 	       rdma_req->state == RDMA_REQUEST_STATE_COMPLETING;
3593 }
3594 #endif
3595 
3596 static void
3597 _poller_reset_failed_recvs(struct spdk_nvmf_rdma_poller *rpoller, struct ibv_recv_wr *bad_recv_wr,
3598 			   int rc)
3599 {
3600 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3601 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3602 
3603 	SPDK_ERRLOG("Failed to post a recv for the poller %p with errno %d\n", rpoller, -rc);
3604 	while (bad_recv_wr != NULL) {
3605 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_recv_wr->wr_id;
3606 		rdma_recv = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3607 
3608 		rdma_recv->qpair->current_recv_depth++;
3609 		bad_recv_wr = bad_recv_wr->next;
3610 		SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rdma_recv->qpair, -rc);
3611 		spdk_nvmf_rdma_start_disconnect(rdma_recv->qpair);
3612 	}
3613 }
3614 
3615 static void
3616 _qp_reset_failed_recvs(struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_recv_wr *bad_recv_wr, int rc)
3617 {
3618 	SPDK_ERRLOG("Failed to post a recv for the qpair %p with errno %d\n", rqpair, -rc);
3619 	while (bad_recv_wr != NULL) {
3620 		bad_recv_wr = bad_recv_wr->next;
3621 		rqpair->current_recv_depth++;
3622 	}
3623 	spdk_nvmf_rdma_start_disconnect(rqpair);
3624 }
3625 
3626 static void
3627 _poller_submit_recvs(struct spdk_nvmf_rdma_transport *rtransport,
3628 		     struct spdk_nvmf_rdma_poller *rpoller)
3629 {
3630 	struct spdk_nvmf_rdma_qpair	*rqpair;
3631 	struct ibv_recv_wr		*bad_recv_wr;
3632 	int				rc;
3633 
3634 	if (rpoller->srq) {
3635 		if (rpoller->resources->recvs_to_post.first != NULL) {
3636 			rc = ibv_post_srq_recv(rpoller->srq, rpoller->resources->recvs_to_post.first, &bad_recv_wr);
3637 			if (rc) {
3638 				_poller_reset_failed_recvs(rpoller, bad_recv_wr, rc);
3639 			}
3640 			rpoller->resources->recvs_to_post.first = NULL;
3641 			rpoller->resources->recvs_to_post.last = NULL;
3642 		}
3643 	} else {
3644 		while (!STAILQ_EMPTY(&rpoller->qpairs_pending_recv)) {
3645 			rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_recv);
3646 			assert(rqpair->resources->recvs_to_post.first != NULL);
3647 			rc = ibv_post_recv(rqpair->cm_id->qp, rqpair->resources->recvs_to_post.first, &bad_recv_wr);
3648 			if (rc) {
3649 				_qp_reset_failed_recvs(rqpair, bad_recv_wr, rc);
3650 			}
3651 			rqpair->resources->recvs_to_post.first = NULL;
3652 			rqpair->resources->recvs_to_post.last = NULL;
3653 			STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_recv, recv_link);
3654 		}
3655 	}
3656 }
3657 
3658 static void
3659 _qp_reset_failed_sends(struct spdk_nvmf_rdma_transport *rtransport,
3660 		       struct spdk_nvmf_rdma_qpair *rqpair, struct ibv_send_wr *bad_wr, int rc)
3661 {
3662 	struct spdk_nvmf_rdma_wr	*bad_rdma_wr;
3663 	struct spdk_nvmf_rdma_request	*prev_rdma_req = NULL, *cur_rdma_req = NULL;
3664 
3665 	SPDK_ERRLOG("Failed to post a send for the qpair %p with errno %d\n", rqpair, -rc);
3666 	for (; bad_wr != NULL; bad_wr = bad_wr->next) {
3667 		bad_rdma_wr = (struct spdk_nvmf_rdma_wr *)bad_wr->wr_id;
3668 		assert(rqpair->current_send_depth > 0);
3669 		rqpair->current_send_depth--;
3670 		switch (bad_rdma_wr->type) {
3671 		case RDMA_WR_TYPE_DATA:
3672 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3673 			if (bad_wr->opcode == IBV_WR_RDMA_READ) {
3674 				assert(rqpair->current_read_depth > 0);
3675 				rqpair->current_read_depth--;
3676 			}
3677 			break;
3678 		case RDMA_WR_TYPE_SEND:
3679 			cur_rdma_req = SPDK_CONTAINEROF(bad_rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3680 			break;
3681 		default:
3682 			SPDK_ERRLOG("Found a RECV in the list of pending SEND requests for qpair %p\n", rqpair);
3683 			prev_rdma_req = cur_rdma_req;
3684 			continue;
3685 		}
3686 
3687 		if (prev_rdma_req == cur_rdma_req) {
3688 			/* this request was handled by an earlier wr. i.e. we were performing an nvme read. */
3689 			/* We only have to check against prev_wr since each requests wrs are contiguous in this list. */
3690 			continue;
3691 		}
3692 
3693 		switch (cur_rdma_req->state) {
3694 		case RDMA_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
3695 			cur_rdma_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
3696 			cur_rdma_req->state = RDMA_REQUEST_STATE_READY_TO_COMPLETE;
3697 			break;
3698 		case RDMA_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
3699 		case RDMA_REQUEST_STATE_COMPLETING:
3700 			cur_rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3701 			break;
3702 		default:
3703 			SPDK_ERRLOG("Found a request in a bad state %d when draining pending SEND requests for qpair %p\n",
3704 				    cur_rdma_req->state, rqpair);
3705 			continue;
3706 		}
3707 
3708 		spdk_nvmf_rdma_request_process(rtransport, cur_rdma_req);
3709 		prev_rdma_req = cur_rdma_req;
3710 	}
3711 
3712 	if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3713 		/* Disconnect the connection. */
3714 		spdk_nvmf_rdma_start_disconnect(rqpair);
3715 	}
3716 
3717 }
3718 
3719 static void
3720 _poller_submit_sends(struct spdk_nvmf_rdma_transport *rtransport,
3721 		     struct spdk_nvmf_rdma_poller *rpoller)
3722 {
3723 	struct spdk_nvmf_rdma_qpair	*rqpair;
3724 	struct ibv_send_wr		*bad_wr = NULL;
3725 	int				rc;
3726 
3727 	while (!STAILQ_EMPTY(&rpoller->qpairs_pending_send)) {
3728 		rqpair = STAILQ_FIRST(&rpoller->qpairs_pending_send);
3729 		assert(rqpair->sends_to_post.first != NULL);
3730 		rc = ibv_post_send(rqpair->cm_id->qp, rqpair->sends_to_post.first, &bad_wr);
3731 
3732 		/* bad wr always points to the first wr that failed. */
3733 		if (rc) {
3734 			_qp_reset_failed_sends(rtransport, rqpair, bad_wr, rc);
3735 		}
3736 		rqpair->sends_to_post.first = NULL;
3737 		rqpair->sends_to_post.last = NULL;
3738 		STAILQ_REMOVE_HEAD(&rpoller->qpairs_pending_send, send_link);
3739 	}
3740 }
3741 
3742 static int
3743 spdk_nvmf_rdma_poller_poll(struct spdk_nvmf_rdma_transport *rtransport,
3744 			   struct spdk_nvmf_rdma_poller *rpoller)
3745 {
3746 	struct ibv_wc wc[32];
3747 	struct spdk_nvmf_rdma_wr	*rdma_wr;
3748 	struct spdk_nvmf_rdma_request	*rdma_req;
3749 	struct spdk_nvmf_rdma_recv	*rdma_recv;
3750 	struct spdk_nvmf_rdma_qpair	*rqpair;
3751 	int reaped, i;
3752 	int count = 0;
3753 	bool error = false;
3754 	uint64_t poll_tsc = spdk_get_ticks();
3755 
3756 	/* Poll for completing operations. */
3757 	reaped = ibv_poll_cq(rpoller->cq, 32, wc);
3758 	if (reaped < 0) {
3759 		SPDK_ERRLOG("Error polling CQ! (%d): %s\n",
3760 			    errno, spdk_strerror(errno));
3761 		return -1;
3762 	}
3763 
3764 	rpoller->stat.polls++;
3765 	rpoller->stat.completions += reaped;
3766 
3767 	for (i = 0; i < reaped; i++) {
3768 
3769 		rdma_wr = (struct spdk_nvmf_rdma_wr *)wc[i].wr_id;
3770 
3771 		switch (rdma_wr->type) {
3772 		case RDMA_WR_TYPE_SEND:
3773 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, rsp.rdma_wr);
3774 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3775 
3776 			if (!wc[i].status) {
3777 				count++;
3778 				assert(wc[i].opcode == IBV_WC_SEND);
3779 				assert(spdk_nvmf_rdma_req_is_completing(rdma_req));
3780 			} else {
3781 				SPDK_ERRLOG("data=%p length=%u\n", rdma_req->req.data, rdma_req->req.length);
3782 			}
3783 
3784 			rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3785 			/* +1 for the response wr */
3786 			rqpair->current_send_depth -= rdma_req->num_outstanding_data_wr + 1;
3787 			rdma_req->num_outstanding_data_wr = 0;
3788 
3789 			spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3790 			break;
3791 		case RDMA_WR_TYPE_RECV:
3792 			/* rdma_recv->qpair will be invalid if using an SRQ.  In that case we have to get the qpair from the wc. */
3793 			rdma_recv = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_recv, rdma_wr);
3794 			if (rpoller->srq != NULL) {
3795 				rdma_recv->qpair = get_rdma_qpair_from_wc(rpoller, &wc[i]);
3796 				/* It is possible that there are still some completions for destroyed QP
3797 				 * associated with SRQ. We just ignore these late completions and re-post
3798 				 * receive WRs back to SRQ.
3799 				 */
3800 				if (spdk_unlikely(NULL == rdma_recv->qpair)) {
3801 					struct ibv_recv_wr *bad_wr;
3802 					int rc;
3803 
3804 					rdma_recv->wr.next = NULL;
3805 					rc = ibv_post_srq_recv(rpoller->srq,
3806 							       &rdma_recv->wr,
3807 							       &bad_wr);
3808 					if (rc) {
3809 						SPDK_ERRLOG("Failed to re-post recv WR to SRQ, err %d\n", rc);
3810 					}
3811 					continue;
3812 				}
3813 			}
3814 			rqpair = rdma_recv->qpair;
3815 
3816 			assert(rqpair != NULL);
3817 			if (!wc[i].status) {
3818 				assert(wc[i].opcode == IBV_WC_RECV);
3819 				if (rqpair->current_recv_depth >= rqpair->max_queue_depth) {
3820 					spdk_nvmf_rdma_start_disconnect(rqpair);
3821 					break;
3822 				}
3823 			}
3824 
3825 			rdma_recv->wr.next = NULL;
3826 			rqpair->current_recv_depth++;
3827 			rdma_recv->receive_tsc = poll_tsc;
3828 			rpoller->stat.requests++;
3829 			STAILQ_INSERT_TAIL(&rqpair->resources->incoming_queue, rdma_recv, link);
3830 			break;
3831 		case RDMA_WR_TYPE_DATA:
3832 			rdma_req = SPDK_CONTAINEROF(rdma_wr, struct spdk_nvmf_rdma_request, data.rdma_wr);
3833 			rqpair = SPDK_CONTAINEROF(rdma_req->req.qpair, struct spdk_nvmf_rdma_qpair, qpair);
3834 
3835 			assert(rdma_req->num_outstanding_data_wr > 0);
3836 
3837 			rqpair->current_send_depth--;
3838 			rdma_req->num_outstanding_data_wr--;
3839 			if (!wc[i].status) {
3840 				assert(wc[i].opcode == IBV_WC_RDMA_READ);
3841 				rqpair->current_read_depth--;
3842 				/* wait for all outstanding reads associated with the same rdma_req to complete before proceeding. */
3843 				if (rdma_req->num_outstanding_data_wr == 0) {
3844 					rdma_req->state = RDMA_REQUEST_STATE_READY_TO_EXECUTE;
3845 					spdk_nvmf_rdma_request_process(rtransport, rdma_req);
3846 				}
3847 			} else {
3848 				/* If the data transfer fails still force the queue into the error state,
3849 				 * if we were performing an RDMA_READ, we need to force the request into a
3850 				 * completed state since it wasn't linked to a send. However, in the RDMA_WRITE
3851 				 * case, we should wait for the SEND to complete. */
3852 				SPDK_ERRLOG("data=%p length=%u\n", rdma_req->req.data, rdma_req->req.length);
3853 				if (rdma_req->data.wr.opcode == IBV_WR_RDMA_READ) {
3854 					rqpair->current_read_depth--;
3855 					if (rdma_req->num_outstanding_data_wr == 0) {
3856 						rdma_req->state = RDMA_REQUEST_STATE_COMPLETED;
3857 					}
3858 				}
3859 			}
3860 			break;
3861 		default:
3862 			SPDK_ERRLOG("Received an unknown opcode on the CQ: %d\n", wc[i].opcode);
3863 			continue;
3864 		}
3865 
3866 		/* Handle error conditions */
3867 		if (wc[i].status) {
3868 			SPDK_DEBUGLOG(SPDK_LOG_RDMA, "CQ error on CQ %p, Request 0x%lu (%d): %s\n",
3869 				      rpoller->cq, wc[i].wr_id, wc[i].status, ibv_wc_status_str(wc[i].status));
3870 
3871 			error = true;
3872 
3873 			if (rqpair->qpair.state == SPDK_NVMF_QPAIR_ACTIVE) {
3874 				/* Disconnect the connection. */
3875 				spdk_nvmf_rdma_start_disconnect(rqpair);
3876 			} else {
3877 				nvmf_rdma_destroy_drained_qpair(rqpair);
3878 			}
3879 			continue;
3880 		}
3881 
3882 		spdk_nvmf_rdma_qpair_process_pending(rtransport, rqpair, false);
3883 
3884 		if (rqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
3885 			nvmf_rdma_destroy_drained_qpair(rqpair);
3886 		}
3887 	}
3888 
3889 	if (error == true) {
3890 		return -1;
3891 	}
3892 
3893 	/* submit outstanding work requests. */
3894 	_poller_submit_recvs(rtransport, rpoller);
3895 	_poller_submit_sends(rtransport, rpoller);
3896 
3897 	return count;
3898 }
3899 
3900 static int
3901 spdk_nvmf_rdma_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3902 {
3903 	struct spdk_nvmf_rdma_transport *rtransport;
3904 	struct spdk_nvmf_rdma_poll_group *rgroup;
3905 	struct spdk_nvmf_rdma_poller	*rpoller;
3906 	int				count, rc;
3907 
3908 	rtransport = SPDK_CONTAINEROF(group->transport, struct spdk_nvmf_rdma_transport, transport);
3909 	rgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_rdma_poll_group, group);
3910 
3911 	count = 0;
3912 	TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
3913 		rc = spdk_nvmf_rdma_poller_poll(rtransport, rpoller);
3914 		if (rc < 0) {
3915 			return rc;
3916 		}
3917 		count += rc;
3918 	}
3919 
3920 	return count;
3921 }
3922 
3923 static int
3924 spdk_nvmf_rdma_trid_from_cm_id(struct rdma_cm_id *id,
3925 			       struct spdk_nvme_transport_id *trid,
3926 			       bool peer)
3927 {
3928 	struct sockaddr *saddr;
3929 	uint16_t port;
3930 
3931 	trid->trtype = SPDK_NVME_TRANSPORT_RDMA;
3932 
3933 	if (peer) {
3934 		saddr = rdma_get_peer_addr(id);
3935 	} else {
3936 		saddr = rdma_get_local_addr(id);
3937 	}
3938 	switch (saddr->sa_family) {
3939 	case AF_INET: {
3940 		struct sockaddr_in *saddr_in = (struct sockaddr_in *)saddr;
3941 
3942 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3943 		inet_ntop(AF_INET, &saddr_in->sin_addr,
3944 			  trid->traddr, sizeof(trid->traddr));
3945 		if (peer) {
3946 			port = ntohs(rdma_get_dst_port(id));
3947 		} else {
3948 			port = ntohs(rdma_get_src_port(id));
3949 		}
3950 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3951 		break;
3952 	}
3953 	case AF_INET6: {
3954 		struct sockaddr_in6 *saddr_in = (struct sockaddr_in6 *)saddr;
3955 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3956 		inet_ntop(AF_INET6, &saddr_in->sin6_addr,
3957 			  trid->traddr, sizeof(trid->traddr));
3958 		if (peer) {
3959 			port = ntohs(rdma_get_dst_port(id));
3960 		} else {
3961 			port = ntohs(rdma_get_src_port(id));
3962 		}
3963 		snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%u", port);
3964 		break;
3965 	}
3966 	default:
3967 		return -1;
3968 
3969 	}
3970 
3971 	return 0;
3972 }
3973 
3974 static int
3975 spdk_nvmf_rdma_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
3976 				   struct spdk_nvme_transport_id *trid)
3977 {
3978 	struct spdk_nvmf_rdma_qpair	*rqpair;
3979 
3980 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3981 
3982 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, true);
3983 }
3984 
3985 static int
3986 spdk_nvmf_rdma_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
3987 				    struct spdk_nvme_transport_id *trid)
3988 {
3989 	struct spdk_nvmf_rdma_qpair	*rqpair;
3990 
3991 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
3992 
3993 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->cm_id, trid, false);
3994 }
3995 
3996 static int
3997 spdk_nvmf_rdma_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
3998 				     struct spdk_nvme_transport_id *trid)
3999 {
4000 	struct spdk_nvmf_rdma_qpair	*rqpair;
4001 
4002 	rqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_rdma_qpair, qpair);
4003 
4004 	return spdk_nvmf_rdma_trid_from_cm_id(rqpair->listen_id, trid, false);
4005 }
4006 
4007 void
4008 spdk_nvmf_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks)
4009 {
4010 	g_nvmf_hooks = *hooks;
4011 }
4012 
4013 static int
4014 spdk_nvmf_rdma_poll_group_get_stat(struct spdk_nvmf_tgt *tgt,
4015 				   struct spdk_nvmf_transport_poll_group_stat **stat)
4016 {
4017 	struct spdk_io_channel *ch;
4018 	struct spdk_nvmf_poll_group *group;
4019 	struct spdk_nvmf_transport_poll_group *tgroup;
4020 	struct spdk_nvmf_rdma_poll_group *rgroup;
4021 	struct spdk_nvmf_rdma_poller *rpoller;
4022 	struct spdk_nvmf_rdma_device_stat *device_stat;
4023 	uint64_t num_devices = 0;
4024 
4025 	if (tgt == NULL || stat == NULL) {
4026 		return -EINVAL;
4027 	}
4028 
4029 	ch = spdk_get_io_channel(tgt);
4030 	group = spdk_io_channel_get_ctx(ch);;
4031 	spdk_put_io_channel(ch);
4032 	TAILQ_FOREACH(tgroup, &group->tgroups, link) {
4033 		if (SPDK_NVME_TRANSPORT_RDMA == tgroup->transport->ops->type) {
4034 			*stat = calloc(1, sizeof(struct spdk_nvmf_transport_poll_group_stat));
4035 			if (!*stat) {
4036 				SPDK_ERRLOG("Failed to allocate memory for NVMf RDMA statistics\n");
4037 				return -ENOMEM;
4038 			}
4039 			(*stat)->trtype = SPDK_NVME_TRANSPORT_RDMA;
4040 
4041 			rgroup = SPDK_CONTAINEROF(tgroup, struct spdk_nvmf_rdma_poll_group, group);
4042 			/* Count devices to allocate enough memory */
4043 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4044 				++num_devices;
4045 			}
4046 			(*stat)->rdma.devices = calloc(num_devices, sizeof(struct spdk_nvmf_rdma_device_stat));
4047 			if (!(*stat)->rdma.devices) {
4048 				SPDK_ERRLOG("Failed to allocate NVMf RDMA devices statistics\n");
4049 				free(*stat);
4050 				return -ENOMEM;
4051 			}
4052 
4053 			(*stat)->rdma.pending_data_buffer = rgroup->stat.pending_data_buffer;
4054 			(*stat)->rdma.num_devices = num_devices;
4055 			num_devices = 0;
4056 			TAILQ_FOREACH(rpoller, &rgroup->pollers, link) {
4057 				device_stat = &(*stat)->rdma.devices[num_devices++];
4058 				device_stat->name = ibv_get_device_name(rpoller->device->context->device);
4059 				device_stat->polls = rpoller->stat.polls;
4060 				device_stat->completions = rpoller->stat.completions;
4061 				device_stat->requests = rpoller->stat.requests;
4062 				device_stat->request_latency = rpoller->stat.request_latency;
4063 				device_stat->pending_free_request = rpoller->stat.pending_free_request;
4064 				device_stat->pending_rdma_read = rpoller->stat.pending_rdma_read;
4065 				device_stat->pending_rdma_write = rpoller->stat.pending_rdma_write;
4066 			}
4067 			return 0;
4068 		}
4069 	}
4070 	return -ENOENT;
4071 }
4072 
4073 static void
4074 spdk_nvmf_rdma_poll_group_free_stat(struct spdk_nvmf_transport_poll_group_stat *stat)
4075 {
4076 	if (stat) {
4077 		free(stat->rdma.devices);
4078 	}
4079 	free(stat);
4080 }
4081 
4082 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_rdma = {
4083 	.type = SPDK_NVME_TRANSPORT_RDMA,
4084 	.opts_init = spdk_nvmf_rdma_opts_init,
4085 	.create = spdk_nvmf_rdma_create,
4086 	.destroy = spdk_nvmf_rdma_destroy,
4087 
4088 	.listen = spdk_nvmf_rdma_listen,
4089 	.stop_listen = spdk_nvmf_rdma_stop_listen,
4090 	.accept = spdk_nvmf_rdma_accept,
4091 
4092 	.listener_discover = spdk_nvmf_rdma_discover,
4093 
4094 	.poll_group_create = spdk_nvmf_rdma_poll_group_create,
4095 	.get_optimal_poll_group = spdk_nvmf_rdma_get_optimal_poll_group,
4096 	.poll_group_destroy = spdk_nvmf_rdma_poll_group_destroy,
4097 	.poll_group_add = spdk_nvmf_rdma_poll_group_add,
4098 	.poll_group_poll = spdk_nvmf_rdma_poll_group_poll,
4099 
4100 	.req_free = spdk_nvmf_rdma_request_free,
4101 	.req_complete = spdk_nvmf_rdma_request_complete,
4102 
4103 	.qpair_fini = spdk_nvmf_rdma_close_qpair,
4104 	.qpair_get_peer_trid = spdk_nvmf_rdma_qpair_get_peer_trid,
4105 	.qpair_get_local_trid = spdk_nvmf_rdma_qpair_get_local_trid,
4106 	.qpair_get_listen_trid = spdk_nvmf_rdma_qpair_get_listen_trid,
4107 
4108 	.poll_group_get_stat = spdk_nvmf_rdma_poll_group_get_stat,
4109 	.poll_group_free_stat = spdk_nvmf_rdma_poll_group_free_stat,
4110 };
4111 
4112 SPDK_LOG_REGISTER_COMPONENT("rdma", SPDK_LOG_RDMA)
4113