xref: /spdk/lib/nvmf/tcp.c (revision 8d30c85aa564da78f3e1382a3b15e29b262c0bce)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (C) 2018 Intel Corporation. All rights reserved.
3  *   Copyright (c) 2019, 2020 Mellanox Technologies LTD. All rights reserved.
4  *   Copyright (c) 2022 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
5  */
6 
7 #include "spdk/accel.h"
8 #include "spdk/stdinc.h"
9 #include "spdk/crc32.h"
10 #include "spdk/endian.h"
11 #include "spdk/assert.h"
12 #include "spdk/thread.h"
13 #include "spdk/nvmf_transport.h"
14 #include "spdk/string.h"
15 #include "spdk/trace.h"
16 #include "spdk/util.h"
17 #include "spdk/log.h"
18 
19 #include "spdk_internal/assert.h"
20 #include "spdk_internal/nvme_tcp.h"
21 #include "spdk_internal/sock.h"
22 
23 #include "nvmf_internal.h"
24 
25 #include "spdk_internal/trace_defs.h"
26 
27 #define NVMF_TCP_MAX_ACCEPT_SOCK_ONE_TIME 16
28 #define SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY 16
29 #define SPDK_NVMF_TCP_DEFAULT_SOCK_PRIORITY 0
30 #define SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM 32
31 #define SPDK_NVMF_TCP_DEFAULT_SUCCESS_OPTIMIZATION true
32 
33 #define SPDK_NVMF_TCP_MIN_IO_QUEUE_DEPTH 2
34 #define SPDK_NVMF_TCP_MAX_IO_QUEUE_DEPTH 65535
35 #define SPDK_NVMF_TCP_MIN_ADMIN_QUEUE_DEPTH 2
36 #define SPDK_NVMF_TCP_MAX_ADMIN_QUEUE_DEPTH 4096
37 
38 #define SPDK_NVMF_TCP_DEFAULT_MAX_IO_QUEUE_DEPTH 128
39 #define SPDK_NVMF_TCP_DEFAULT_MAX_ADMIN_QUEUE_DEPTH 128
40 #define SPDK_NVMF_TCP_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
41 #define SPDK_NVMF_TCP_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
42 #define SPDK_NVMF_TCP_DEFAULT_MAX_IO_SIZE 131072
43 #define SPDK_NVMF_TCP_DEFAULT_IO_UNIT_SIZE 131072
44 #define SPDK_NVMF_TCP_DEFAULT_NUM_SHARED_BUFFERS 511
45 #define SPDK_NVMF_TCP_DEFAULT_BUFFER_CACHE_SIZE UINT32_MAX
46 #define SPDK_NVMF_TCP_DEFAULT_DIF_INSERT_OR_STRIP false
47 #define SPDK_NVMF_TCP_DEFAULT_ABORT_TIMEOUT_SEC 1
48 
49 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_tcp;
50 
51 /* spdk nvmf related structure */
52 enum spdk_nvmf_tcp_req_state {
53 
54 	/* The request is not currently in use */
55 	TCP_REQUEST_STATE_FREE = 0,
56 
57 	/* Initial state when request first received */
58 	TCP_REQUEST_STATE_NEW = 1,
59 
60 	/* The request is queued until a data buffer is available. */
61 	TCP_REQUEST_STATE_NEED_BUFFER = 2,
62 
63 	/* The request is waiting for zcopy_start to finish */
64 	TCP_REQUEST_STATE_AWAITING_ZCOPY_START = 3,
65 
66 	/* The request has received a zero-copy buffer */
67 	TCP_REQUEST_STATE_ZCOPY_START_COMPLETED = 4,
68 
69 	/* The request is currently transferring data from the host to the controller. */
70 	TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER = 5,
71 
72 	/* The request is waiting for the R2T send acknowledgement. */
73 	TCP_REQUEST_STATE_AWAITING_R2T_ACK = 6,
74 
75 	/* The request is ready to execute at the block device */
76 	TCP_REQUEST_STATE_READY_TO_EXECUTE = 7,
77 
78 	/* The request is currently executing at the block device */
79 	TCP_REQUEST_STATE_EXECUTING = 8,
80 
81 	/* The request is waiting for zcopy buffers to be committed */
82 	TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT = 9,
83 
84 	/* The request finished executing at the block device */
85 	TCP_REQUEST_STATE_EXECUTED = 10,
86 
87 	/* The request is ready to send a completion */
88 	TCP_REQUEST_STATE_READY_TO_COMPLETE = 11,
89 
90 	/* The request is currently transferring final pdus from the controller to the host. */
91 	TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST = 12,
92 
93 	/* The request is waiting for zcopy buffers to be released (without committing) */
94 	TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE = 13,
95 
96 	/* The request completed and can be marked free. */
97 	TCP_REQUEST_STATE_COMPLETED = 14,
98 
99 	/* Terminator */
100 	TCP_REQUEST_NUM_STATES,
101 };
102 
103 static const char *spdk_nvmf_tcp_term_req_fes_str[] = {
104 	"Invalid PDU Header Field",
105 	"PDU Sequence Error",
106 	"Header Digiest Error",
107 	"Data Transfer Out of Range",
108 	"R2T Limit Exceeded",
109 	"Unsupported parameter",
110 };
111 
112 SPDK_TRACE_REGISTER_FN(nvmf_tcp_trace, "nvmf_tcp", TRACE_GROUP_NVMF_TCP)
113 {
114 	spdk_trace_register_owner(OWNER_NVMF_TCP, 't');
115 	spdk_trace_register_object(OBJECT_NVMF_TCP_IO, 'r');
116 	spdk_trace_register_description("TCP_REQ_NEW",
117 					TRACE_TCP_REQUEST_STATE_NEW,
118 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 1,
119 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
120 	spdk_trace_register_description("TCP_REQ_NEED_BUFFER",
121 					TRACE_TCP_REQUEST_STATE_NEED_BUFFER,
122 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
123 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
124 	spdk_trace_register_description("TCP_REQ_WAIT_ZCPY_START",
125 					TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_START,
126 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
127 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
128 	spdk_trace_register_description("TCP_REQ_ZCPY_START_CPL",
129 					TRACE_TCP_REQUEST_STATE_ZCOPY_START_COMPLETED,
130 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
131 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
132 	spdk_trace_register_description("TCP_REQ_TX_H_TO_C",
133 					TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
134 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
135 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
136 	spdk_trace_register_description("TCP_REQ_RDY_TO_EXECUTE",
137 					TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE,
138 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
139 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
140 	spdk_trace_register_description("TCP_REQ_EXECUTING",
141 					TRACE_TCP_REQUEST_STATE_EXECUTING,
142 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
143 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
144 	spdk_trace_register_description("TCP_REQ_WAIT_ZCPY_CMT",
145 					TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_COMMIT,
146 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
147 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
148 	spdk_trace_register_description("TCP_REQ_EXECUTED",
149 					TRACE_TCP_REQUEST_STATE_EXECUTED,
150 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
151 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
152 	spdk_trace_register_description("TCP_REQ_RDY_TO_COMPLETE",
153 					TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE,
154 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
155 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
156 	spdk_trace_register_description("TCP_REQ_TRANSFER_C2H",
157 					TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
158 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
159 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
160 	spdk_trace_register_description("TCP_REQ_AWAIT_ZCPY_RLS",
161 					TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_RELEASE,
162 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
163 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
164 	spdk_trace_register_description("TCP_REQ_COMPLETED",
165 					TRACE_TCP_REQUEST_STATE_COMPLETED,
166 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
167 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
168 	spdk_trace_register_description("TCP_WRITE_START",
169 					TRACE_TCP_FLUSH_WRITEBUF_START,
170 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
171 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
172 	spdk_trace_register_description("TCP_WRITE_DONE",
173 					TRACE_TCP_FLUSH_WRITEBUF_DONE,
174 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
175 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
176 	spdk_trace_register_description("TCP_READ_DONE",
177 					TRACE_TCP_READ_FROM_SOCKET_DONE,
178 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
179 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
180 	spdk_trace_register_description("TCP_REQ_AWAIT_R2T_ACK",
181 					TRACE_TCP_REQUEST_STATE_AWAIT_R2T_ACK,
182 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
183 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
184 
185 	spdk_trace_register_description("TCP_QP_CREATE", TRACE_TCP_QP_CREATE,
186 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
187 					SPDK_TRACE_ARG_TYPE_INT, "");
188 	spdk_trace_register_description("TCP_QP_SOCK_INIT", TRACE_TCP_QP_SOCK_INIT,
189 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
190 					SPDK_TRACE_ARG_TYPE_INT, "");
191 	spdk_trace_register_description("TCP_QP_STATE_CHANGE", TRACE_TCP_QP_STATE_CHANGE,
192 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
193 					SPDK_TRACE_ARG_TYPE_INT, "state");
194 	spdk_trace_register_description("TCP_QP_DISCONNECT", TRACE_TCP_QP_DISCONNECT,
195 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
196 					SPDK_TRACE_ARG_TYPE_INT, "");
197 	spdk_trace_register_description("TCP_QP_DESTROY", TRACE_TCP_QP_DESTROY,
198 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
199 					SPDK_TRACE_ARG_TYPE_INT, "");
200 	spdk_trace_register_description("TCP_QP_ABORT_REQ", TRACE_TCP_QP_ABORT_REQ,
201 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
202 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
203 	spdk_trace_register_description("TCP_QP_RCV_STATE_CHANGE", TRACE_TCP_QP_RCV_STATE_CHANGE,
204 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
205 					SPDK_TRACE_ARG_TYPE_INT, "state");
206 
207 	spdk_trace_tpoint_register_relation(TRACE_BDEV_IO_START, OBJECT_NVMF_TCP_IO, 1);
208 	spdk_trace_tpoint_register_relation(TRACE_BDEV_IO_DONE, OBJECT_NVMF_TCP_IO, 0);
209 }
210 
211 struct spdk_nvmf_tcp_req  {
212 	struct spdk_nvmf_request		req;
213 	struct spdk_nvme_cpl			rsp;
214 	struct spdk_nvme_cmd			cmd;
215 
216 	/* A PDU that can be used for sending responses. This is
217 	 * not the incoming PDU! */
218 	struct nvme_tcp_pdu			*pdu;
219 
220 	/* In-capsule data buffer */
221 	uint8_t					*buf;
222 
223 	struct spdk_nvmf_tcp_req		*fused_pair;
224 
225 	/*
226 	 * The PDU for a request may be used multiple times in serial over
227 	 * the request's lifetime. For example, first to send an R2T, then
228 	 * to send a completion. To catch mistakes where the PDU is used
229 	 * twice at the same time, add a debug flag here for init/fini.
230 	 */
231 	bool					pdu_in_use;
232 	bool					has_in_capsule_data;
233 	bool					fused_failed;
234 
235 	/* transfer_tag */
236 	uint16_t				ttag;
237 
238 	enum spdk_nvmf_tcp_req_state		state;
239 
240 	/*
241 	 * h2c_offset is used when we receive the h2c_data PDU.
242 	 */
243 	uint32_t				h2c_offset;
244 
245 	STAILQ_ENTRY(spdk_nvmf_tcp_req)		link;
246 	TAILQ_ENTRY(spdk_nvmf_tcp_req)		state_link;
247 };
248 
249 struct spdk_nvmf_tcp_qpair {
250 	struct spdk_nvmf_qpair			qpair;
251 	struct spdk_nvmf_tcp_poll_group		*group;
252 	struct spdk_sock			*sock;
253 
254 	enum nvme_tcp_pdu_recv_state		recv_state;
255 	enum nvme_tcp_qpair_state		state;
256 
257 	/* PDU being actively received */
258 	struct nvme_tcp_pdu			*pdu_in_progress;
259 
260 	struct spdk_nvmf_tcp_req		*fused_first;
261 
262 	/* Queues to track the requests in all states */
263 	TAILQ_HEAD(, spdk_nvmf_tcp_req)		tcp_req_working_queue;
264 	TAILQ_HEAD(, spdk_nvmf_tcp_req)		tcp_req_free_queue;
265 	SLIST_HEAD(, nvme_tcp_pdu)		tcp_pdu_free_queue;
266 	/* Number of working pdus */
267 	uint32_t				tcp_pdu_working_count;
268 
269 	/* Number of requests in each state */
270 	uint32_t				state_cntr[TCP_REQUEST_NUM_STATES];
271 
272 	uint8_t					cpda;
273 
274 	bool					host_hdgst_enable;
275 	bool					host_ddgst_enable;
276 
277 	/* This is a spare PDU used for sending special management
278 	 * operations. Primarily, this is used for the initial
279 	 * connection response and c2h termination request. */
280 	struct nvme_tcp_pdu			*mgmt_pdu;
281 
282 	/* Arrays of in-capsule buffers, requests, and pdus.
283 	 * Each array is 'resource_count' number of elements */
284 	void					*bufs;
285 	struct spdk_nvmf_tcp_req		*reqs;
286 	struct nvme_tcp_pdu			*pdus;
287 	uint32_t				resource_count;
288 	uint32_t				recv_buf_size;
289 
290 	struct spdk_nvmf_tcp_port		*port;
291 
292 	/* IP address */
293 	char					initiator_addr[SPDK_NVMF_TRADDR_MAX_LEN];
294 	char					target_addr[SPDK_NVMF_TRADDR_MAX_LEN];
295 
296 	/* IP port */
297 	uint16_t				initiator_port;
298 	uint16_t				target_port;
299 
300 	/* Timer used to destroy qpair after detecting transport error issue if initiator does
301 	 *  not close the connection.
302 	 */
303 	struct spdk_poller			*timeout_poller;
304 
305 	spdk_nvmf_transport_qpair_fini_cb	fini_cb_fn;
306 	void					*fini_cb_arg;
307 
308 	TAILQ_ENTRY(spdk_nvmf_tcp_qpair)	link;
309 };
310 
311 struct spdk_nvmf_tcp_control_msg {
312 	STAILQ_ENTRY(spdk_nvmf_tcp_control_msg) link;
313 };
314 
315 struct spdk_nvmf_tcp_control_msg_list {
316 	void *msg_buf;
317 	STAILQ_HEAD(, spdk_nvmf_tcp_control_msg) free_msgs;
318 };
319 
320 struct spdk_nvmf_tcp_poll_group {
321 	struct spdk_nvmf_transport_poll_group	group;
322 	struct spdk_sock_group			*sock_group;
323 
324 	TAILQ_HEAD(, spdk_nvmf_tcp_qpair)	qpairs;
325 	TAILQ_HEAD(, spdk_nvmf_tcp_qpair)	await_req;
326 
327 	struct spdk_io_channel			*accel_channel;
328 	struct spdk_nvmf_tcp_control_msg_list	*control_msg_list;
329 
330 	TAILQ_ENTRY(spdk_nvmf_tcp_poll_group)	link;
331 };
332 
333 struct spdk_nvmf_tcp_port {
334 	const struct spdk_nvme_transport_id	*trid;
335 	struct spdk_sock			*listen_sock;
336 	TAILQ_ENTRY(spdk_nvmf_tcp_port)		link;
337 };
338 
339 struct tcp_transport_opts {
340 	bool		c2h_success;
341 	uint16_t	control_msg_num;
342 	uint32_t	sock_priority;
343 };
344 
345 struct tcp_psk_entry {
346 	char				hostnqn[SPDK_NVMF_NQN_MAX_LEN + 1];
347 	char				subnqn[SPDK_NVMF_NQN_MAX_LEN + 1];
348 	char				psk_identity[NVMF_PSK_IDENTITY_LEN];
349 	uint8_t				psk[SPDK_TLS_PSK_MAX_LEN];
350 	uint32_t			psk_size;
351 	TAILQ_ENTRY(tcp_psk_entry)	link;
352 };
353 
354 struct spdk_nvmf_tcp_transport {
355 	struct spdk_nvmf_transport		transport;
356 	struct tcp_transport_opts               tcp_opts;
357 
358 	struct spdk_nvmf_tcp_poll_group		*next_pg;
359 
360 	struct spdk_poller			*accept_poller;
361 
362 	TAILQ_HEAD(, spdk_nvmf_tcp_port)	ports;
363 	TAILQ_HEAD(, spdk_nvmf_tcp_poll_group)	poll_groups;
364 
365 	TAILQ_HEAD(, tcp_psk_entry)		psks;
366 };
367 
368 static const struct spdk_json_object_decoder tcp_transport_opts_decoder[] = {
369 	{
370 		"c2h_success", offsetof(struct tcp_transport_opts, c2h_success),
371 		spdk_json_decode_bool, true
372 	},
373 	{
374 		"control_msg_num", offsetof(struct tcp_transport_opts, control_msg_num),
375 		spdk_json_decode_uint16, true
376 	},
377 	{
378 		"sock_priority", offsetof(struct tcp_transport_opts, sock_priority),
379 		spdk_json_decode_uint32, true
380 	},
381 };
382 
383 static bool nvmf_tcp_req_process(struct spdk_nvmf_tcp_transport *ttransport,
384 				 struct spdk_nvmf_tcp_req *tcp_req);
385 static void nvmf_tcp_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
386 
387 static void _nvmf_tcp_send_c2h_data(struct spdk_nvmf_tcp_qpair *tqpair,
388 				    struct spdk_nvmf_tcp_req *tcp_req);
389 
390 static inline void
391 nvmf_tcp_req_set_state(struct spdk_nvmf_tcp_req *tcp_req,
392 		       enum spdk_nvmf_tcp_req_state state)
393 {
394 	struct spdk_nvmf_qpair *qpair;
395 	struct spdk_nvmf_tcp_qpair *tqpair;
396 
397 	qpair = tcp_req->req.qpair;
398 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
399 
400 	assert(tqpair->state_cntr[tcp_req->state] > 0);
401 	tqpair->state_cntr[tcp_req->state]--;
402 	tqpair->state_cntr[state]++;
403 
404 	tcp_req->state = state;
405 }
406 
407 static inline struct nvme_tcp_pdu *
408 nvmf_tcp_req_pdu_init(struct spdk_nvmf_tcp_req *tcp_req)
409 {
410 	assert(tcp_req->pdu_in_use == false);
411 
412 	memset(tcp_req->pdu, 0, sizeof(*tcp_req->pdu));
413 	tcp_req->pdu->qpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
414 
415 	return tcp_req->pdu;
416 }
417 
418 static struct spdk_nvmf_tcp_req *
419 nvmf_tcp_req_get(struct spdk_nvmf_tcp_qpair *tqpair)
420 {
421 	struct spdk_nvmf_tcp_req *tcp_req;
422 
423 	tcp_req = TAILQ_FIRST(&tqpair->tcp_req_free_queue);
424 	if (spdk_unlikely(!tcp_req)) {
425 		return NULL;
426 	}
427 
428 	memset(&tcp_req->rsp, 0, sizeof(tcp_req->rsp));
429 	tcp_req->h2c_offset = 0;
430 	tcp_req->has_in_capsule_data = false;
431 	tcp_req->req.dif_enabled = false;
432 	tcp_req->req.zcopy_phase = NVMF_ZCOPY_PHASE_NONE;
433 
434 	TAILQ_REMOVE(&tqpair->tcp_req_free_queue, tcp_req, state_link);
435 	TAILQ_INSERT_TAIL(&tqpair->tcp_req_working_queue, tcp_req, state_link);
436 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEW);
437 	return tcp_req;
438 }
439 
440 static inline void
441 nvmf_tcp_req_put(struct spdk_nvmf_tcp_qpair *tqpair, struct spdk_nvmf_tcp_req *tcp_req)
442 {
443 	assert(!tcp_req->pdu_in_use);
444 
445 	TAILQ_REMOVE(&tqpair->tcp_req_working_queue, tcp_req, state_link);
446 	TAILQ_INSERT_TAIL(&tqpair->tcp_req_free_queue, tcp_req, state_link);
447 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_FREE);
448 }
449 
450 static void
451 nvmf_tcp_request_free(void *cb_arg)
452 {
453 	struct spdk_nvmf_tcp_transport *ttransport;
454 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
455 
456 	assert(tcp_req != NULL);
457 
458 	SPDK_DEBUGLOG(nvmf_tcp, "tcp_req=%p will be freed\n", tcp_req);
459 	ttransport = SPDK_CONTAINEROF(tcp_req->req.qpair->transport,
460 				      struct spdk_nvmf_tcp_transport, transport);
461 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
462 	nvmf_tcp_req_process(ttransport, tcp_req);
463 }
464 
465 static int
466 nvmf_tcp_req_free(struct spdk_nvmf_request *req)
467 {
468 	struct spdk_nvmf_tcp_req *tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
469 
470 	nvmf_tcp_request_free(tcp_req);
471 
472 	return 0;
473 }
474 
475 static void
476 nvmf_tcp_drain_state_queue(struct spdk_nvmf_tcp_qpair *tqpair,
477 			   enum spdk_nvmf_tcp_req_state state)
478 {
479 	struct spdk_nvmf_tcp_req *tcp_req, *req_tmp;
480 
481 	assert(state != TCP_REQUEST_STATE_FREE);
482 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->tcp_req_working_queue, state_link, req_tmp) {
483 		if (state == tcp_req->state) {
484 			nvmf_tcp_request_free(tcp_req);
485 		}
486 	}
487 }
488 
489 static void
490 nvmf_tcp_cleanup_all_states(struct spdk_nvmf_tcp_qpair *tqpair)
491 {
492 	struct spdk_nvmf_tcp_req *tcp_req, *req_tmp;
493 
494 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST);
495 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_NEW);
496 
497 	/* Wipe the requests waiting for buffer from the global list */
498 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->tcp_req_working_queue, state_link, req_tmp) {
499 		if (tcp_req->state == TCP_REQUEST_STATE_NEED_BUFFER) {
500 			STAILQ_REMOVE(&tqpair->group->group.pending_buf_queue, &tcp_req->req,
501 				      spdk_nvmf_request, buf_link);
502 		}
503 	}
504 
505 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_NEED_BUFFER);
506 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_EXECUTING);
507 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
508 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_AWAITING_R2T_ACK);
509 }
510 
511 static void
512 nvmf_tcp_dump_qpair_req_contents(struct spdk_nvmf_tcp_qpair *tqpair)
513 {
514 	int i;
515 	struct spdk_nvmf_tcp_req *tcp_req;
516 
517 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", tqpair->qpair.qid);
518 	for (i = 1; i < TCP_REQUEST_NUM_STATES; i++) {
519 		SPDK_ERRLOG("\tNum of requests in state[%d] = %u\n", i, tqpair->state_cntr[i]);
520 		TAILQ_FOREACH(tcp_req, &tqpair->tcp_req_working_queue, state_link) {
521 			if ((int)tcp_req->state == i) {
522 				SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", tcp_req->req.data_from_pool);
523 				SPDK_ERRLOG("\t\tRequest opcode: %d\n", tcp_req->req.cmd->nvmf_cmd.opcode);
524 			}
525 		}
526 	}
527 }
528 
529 static void
530 _nvmf_tcp_qpair_destroy(void *_tqpair)
531 {
532 	struct spdk_nvmf_tcp_qpair *tqpair = _tqpair;
533 	spdk_nvmf_transport_qpair_fini_cb cb_fn = tqpair->fini_cb_fn;
534 	void *cb_arg = tqpair->fini_cb_arg;
535 	int err = 0;
536 
537 	spdk_trace_record(TRACE_TCP_QP_DESTROY, 0, 0, (uintptr_t)tqpair);
538 
539 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
540 
541 	err = spdk_sock_close(&tqpair->sock);
542 	assert(err == 0);
543 	nvmf_tcp_cleanup_all_states(tqpair);
544 
545 	if (tqpair->state_cntr[TCP_REQUEST_STATE_FREE] != tqpair->resource_count) {
546 		SPDK_ERRLOG("tqpair(%p) free tcp request num is %u but should be %u\n", tqpair,
547 			    tqpair->state_cntr[TCP_REQUEST_STATE_FREE],
548 			    tqpair->resource_count);
549 		err++;
550 	}
551 
552 	if (err > 0) {
553 		nvmf_tcp_dump_qpair_req_contents(tqpair);
554 	}
555 
556 	/* The timeout poller might still be registered here if we close the qpair before host
557 	 * terminates the connection.
558 	 */
559 	spdk_poller_unregister(&tqpair->timeout_poller);
560 	spdk_dma_free(tqpair->pdus);
561 	free(tqpair->reqs);
562 	spdk_free(tqpair->bufs);
563 	free(tqpair);
564 
565 	if (cb_fn != NULL) {
566 		cb_fn(cb_arg);
567 	}
568 
569 	SPDK_DEBUGLOG(nvmf_tcp, "Leave\n");
570 }
571 
572 static void
573 nvmf_tcp_qpair_destroy(struct spdk_nvmf_tcp_qpair *tqpair)
574 {
575 	/* Delay the destruction to make sure it isn't performed from the context of a sock
576 	 * callback.  Otherwise, spdk_sock_close() might not abort pending requests, causing their
577 	 * completions to be executed after the qpair is freed.  (Note: this fixed issue #2471.)
578 	 */
579 	spdk_thread_send_msg(spdk_get_thread(), _nvmf_tcp_qpair_destroy, tqpair);
580 }
581 
582 static void
583 nvmf_tcp_dump_opts(struct spdk_nvmf_transport *transport, struct spdk_json_write_ctx *w)
584 {
585 	struct spdk_nvmf_tcp_transport	*ttransport;
586 	assert(w != NULL);
587 
588 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
589 	spdk_json_write_named_bool(w, "c2h_success", ttransport->tcp_opts.c2h_success);
590 	spdk_json_write_named_uint32(w, "sock_priority", ttransport->tcp_opts.sock_priority);
591 }
592 
593 static int
594 nvmf_tcp_destroy(struct spdk_nvmf_transport *transport,
595 		 spdk_nvmf_transport_destroy_done_cb cb_fn, void *cb_arg)
596 {
597 	struct spdk_nvmf_tcp_transport	*ttransport;
598 	struct tcp_psk_entry *entry, *tmp;
599 
600 	assert(transport != NULL);
601 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
602 
603 	TAILQ_FOREACH_SAFE(entry, &ttransport->psks, link, tmp) {
604 		TAILQ_REMOVE(&ttransport->psks, entry, link);
605 		free(entry);
606 	}
607 
608 	spdk_poller_unregister(&ttransport->accept_poller);
609 	free(ttransport);
610 
611 	if (cb_fn) {
612 		cb_fn(cb_arg);
613 	}
614 	return 0;
615 }
616 
617 static int nvmf_tcp_accept(void *ctx);
618 
619 static struct spdk_nvmf_transport *
620 nvmf_tcp_create(struct spdk_nvmf_transport_opts *opts)
621 {
622 	struct spdk_nvmf_tcp_transport *ttransport;
623 	uint32_t sge_count;
624 	uint32_t min_shared_buffers;
625 
626 	ttransport = calloc(1, sizeof(*ttransport));
627 	if (!ttransport) {
628 		return NULL;
629 	}
630 
631 	TAILQ_INIT(&ttransport->ports);
632 	TAILQ_INIT(&ttransport->poll_groups);
633 	TAILQ_INIT(&ttransport->psks);
634 
635 	ttransport->transport.ops = &spdk_nvmf_transport_tcp;
636 
637 	ttransport->tcp_opts.c2h_success = SPDK_NVMF_TCP_DEFAULT_SUCCESS_OPTIMIZATION;
638 	ttransport->tcp_opts.sock_priority = SPDK_NVMF_TCP_DEFAULT_SOCK_PRIORITY;
639 	ttransport->tcp_opts.control_msg_num = SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM;
640 	if (opts->transport_specific != NULL &&
641 	    spdk_json_decode_object_relaxed(opts->transport_specific, tcp_transport_opts_decoder,
642 					    SPDK_COUNTOF(tcp_transport_opts_decoder),
643 					    &ttransport->tcp_opts)) {
644 		SPDK_ERRLOG("spdk_json_decode_object_relaxed failed\n");
645 		free(ttransport);
646 		return NULL;
647 	}
648 
649 	SPDK_NOTICELOG("*** TCP Transport Init ***\n");
650 
651 	SPDK_INFOLOG(nvmf_tcp, "*** TCP Transport Init ***\n"
652 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
653 		     "  max_io_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
654 		     "  in_capsule_data_size=%d, max_aq_depth=%d\n"
655 		     "  num_shared_buffers=%d, c2h_success=%d,\n"
656 		     "  dif_insert_or_strip=%d, sock_priority=%d\n"
657 		     "  abort_timeout_sec=%d, control_msg_num=%hu\n",
658 		     opts->max_queue_depth,
659 		     opts->max_io_size,
660 		     opts->max_qpairs_per_ctrlr - 1,
661 		     opts->io_unit_size,
662 		     opts->in_capsule_data_size,
663 		     opts->max_aq_depth,
664 		     opts->num_shared_buffers,
665 		     ttransport->tcp_opts.c2h_success,
666 		     opts->dif_insert_or_strip,
667 		     ttransport->tcp_opts.sock_priority,
668 		     opts->abort_timeout_sec,
669 		     ttransport->tcp_opts.control_msg_num);
670 
671 	if (ttransport->tcp_opts.sock_priority > SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY) {
672 		SPDK_ERRLOG("Unsupported socket_priority=%d, the current range is: 0 to %d\n"
673 			    "you can use man 7 socket to view the range of priority under SO_PRIORITY item\n",
674 			    ttransport->tcp_opts.sock_priority, SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY);
675 		free(ttransport);
676 		return NULL;
677 	}
678 
679 	if (ttransport->tcp_opts.control_msg_num == 0 &&
680 	    opts->in_capsule_data_size < SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE) {
681 		SPDK_WARNLOG("TCP param control_msg_num can't be 0 if ICD is less than %u bytes. Using default value %u\n",
682 			     SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE, SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM);
683 		ttransport->tcp_opts.control_msg_num = SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM;
684 	}
685 
686 	/* I/O unit size cannot be larger than max I/O size */
687 	if (opts->io_unit_size > opts->max_io_size) {
688 		SPDK_WARNLOG("TCP param io_unit_size %u can't be larger than max_io_size %u. Using max_io_size as io_unit_size\n",
689 			     opts->io_unit_size, opts->max_io_size);
690 		opts->io_unit_size = opts->max_io_size;
691 	}
692 
693 	/* In capsule data size cannot be larger than max I/O size */
694 	if (opts->in_capsule_data_size > opts->max_io_size) {
695 		SPDK_WARNLOG("TCP param ICD size %u can't be larger than max_io_size %u. Using max_io_size as ICD size\n",
696 			     opts->io_unit_size, opts->max_io_size);
697 		opts->in_capsule_data_size = opts->max_io_size;
698 	}
699 
700 	/* max IO queue depth cannot be smaller than 2 or larger than 65535.
701 	 * We will not check SPDK_NVMF_TCP_MAX_IO_QUEUE_DEPTH, because max_queue_depth is 16bits and always not larger than 64k. */
702 	if (opts->max_queue_depth < SPDK_NVMF_TCP_MIN_IO_QUEUE_DEPTH) {
703 		SPDK_WARNLOG("TCP param max_queue_depth %u can't be smaller than %u or larger than %u. Using default value %u\n",
704 			     opts->max_queue_depth, SPDK_NVMF_TCP_MIN_IO_QUEUE_DEPTH,
705 			     SPDK_NVMF_TCP_MAX_IO_QUEUE_DEPTH, SPDK_NVMF_TCP_DEFAULT_MAX_IO_QUEUE_DEPTH);
706 		opts->max_queue_depth = SPDK_NVMF_TCP_DEFAULT_MAX_IO_QUEUE_DEPTH;
707 	}
708 
709 	/* max admin queue depth cannot be smaller than 2 or larger than 4096 */
710 	if (opts->max_aq_depth < SPDK_NVMF_TCP_MIN_ADMIN_QUEUE_DEPTH ||
711 	    opts->max_aq_depth > SPDK_NVMF_TCP_MAX_ADMIN_QUEUE_DEPTH) {
712 		SPDK_WARNLOG("TCP param max_aq_depth %u can't be smaller than %u or larger than %u. Using default value %u\n",
713 			     opts->max_aq_depth, SPDK_NVMF_TCP_MIN_ADMIN_QUEUE_DEPTH,
714 			     SPDK_NVMF_TCP_MAX_ADMIN_QUEUE_DEPTH, SPDK_NVMF_TCP_DEFAULT_MAX_ADMIN_QUEUE_DEPTH);
715 		opts->max_aq_depth = SPDK_NVMF_TCP_DEFAULT_MAX_ADMIN_QUEUE_DEPTH;
716 	}
717 
718 	sge_count = opts->max_io_size / opts->io_unit_size;
719 	if (sge_count > SPDK_NVMF_MAX_SGL_ENTRIES) {
720 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
721 		free(ttransport);
722 		return NULL;
723 	}
724 
725 	/* If buf_cache_size == UINT32_MAX, we will dynamically pick a cache size later that we know will fit. */
726 	if (opts->buf_cache_size < UINT32_MAX) {
727 		min_shared_buffers = spdk_env_get_core_count() * opts->buf_cache_size;
728 		if (min_shared_buffers > opts->num_shared_buffers) {
729 			SPDK_ERRLOG("There are not enough buffers to satisfy "
730 				    "per-poll group caches for each thread. (%" PRIu32 ") "
731 				    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
732 			SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
733 			free(ttransport);
734 			return NULL;
735 		}
736 	}
737 
738 	ttransport->accept_poller = SPDK_POLLER_REGISTER(nvmf_tcp_accept, &ttransport->transport,
739 				    opts->acceptor_poll_rate);
740 	if (!ttransport->accept_poller) {
741 		free(ttransport);
742 		return NULL;
743 	}
744 
745 	return &ttransport->transport;
746 }
747 
748 static int
749 nvmf_tcp_trsvcid_to_int(const char *trsvcid)
750 {
751 	unsigned long long ull;
752 	char *end = NULL;
753 
754 	ull = strtoull(trsvcid, &end, 10);
755 	if (end == NULL || end == trsvcid || *end != '\0') {
756 		return -1;
757 	}
758 
759 	/* Valid TCP/IP port numbers are in [0, 65535] */
760 	if (ull > 65535) {
761 		return -1;
762 	}
763 
764 	return (int)ull;
765 }
766 
767 /**
768  * Canonicalize a listen address trid.
769  */
770 static int
771 nvmf_tcp_canon_listen_trid(struct spdk_nvme_transport_id *canon_trid,
772 			   const struct spdk_nvme_transport_id *trid)
773 {
774 	int trsvcid_int;
775 
776 	trsvcid_int = nvmf_tcp_trsvcid_to_int(trid->trsvcid);
777 	if (trsvcid_int < 0) {
778 		return -EINVAL;
779 	}
780 
781 	memset(canon_trid, 0, sizeof(*canon_trid));
782 	spdk_nvme_trid_populate_transport(canon_trid, SPDK_NVME_TRANSPORT_TCP);
783 	canon_trid->adrfam = trid->adrfam;
784 	snprintf(canon_trid->traddr, sizeof(canon_trid->traddr), "%s", trid->traddr);
785 	snprintf(canon_trid->trsvcid, sizeof(canon_trid->trsvcid), "%d", trsvcid_int);
786 
787 	return 0;
788 }
789 
790 /**
791  * Find an existing listening port.
792  */
793 static struct spdk_nvmf_tcp_port *
794 nvmf_tcp_find_port(struct spdk_nvmf_tcp_transport *ttransport,
795 		   const struct spdk_nvme_transport_id *trid)
796 {
797 	struct spdk_nvme_transport_id canon_trid;
798 	struct spdk_nvmf_tcp_port *port;
799 
800 	if (nvmf_tcp_canon_listen_trid(&canon_trid, trid) != 0) {
801 		return NULL;
802 	}
803 
804 	TAILQ_FOREACH(port, &ttransport->ports, link) {
805 		if (spdk_nvme_transport_id_compare(&canon_trid, port->trid) == 0) {
806 			return port;
807 		}
808 	}
809 
810 	return NULL;
811 }
812 
813 static int
814 tcp_sock_get_key(uint8_t *out, int out_len, const char **cipher, const char *psk_identity,
815 		 void *get_key_ctx)
816 {
817 	struct tcp_psk_entry *entry;
818 	struct spdk_nvmf_tcp_transport *ttransport = get_key_ctx;
819 	size_t psk_len;
820 	int rc;
821 
822 	*cipher = NULL;
823 
824 	TAILQ_FOREACH(entry, &ttransport->psks, link) {
825 		if (strcmp(psk_identity, entry->psk_identity) != 0) {
826 			continue;
827 		}
828 
829 		psk_len = entry->psk_size;
830 		if ((size_t)out_len < psk_len) {
831 			SPDK_ERRLOG("Out buffer of size: %" PRIu32 " cannot fit PSK of len: %lu\n",
832 				    out_len, psk_len);
833 			return -ENOBUFS;
834 		}
835 
836 		/* Convert PSK to the TLS PSK format. */
837 		rc = nvme_tcp_derive_tls_psk(entry->psk, psk_len, psk_identity, out, out_len);
838 		if (rc < 0) {
839 			SPDK_ERRLOG("Could not generate TLS PSK\n");
840 		}
841 
842 		return rc;
843 	}
844 
845 	SPDK_ERRLOG("Could not find PSK for identity: %s\n", psk_identity);
846 
847 	return -EINVAL;
848 }
849 
850 static int
851 nvmf_tcp_listen(struct spdk_nvmf_transport *transport, const struct spdk_nvme_transport_id *trid,
852 		struct spdk_nvmf_listen_opts *listen_opts)
853 {
854 	struct spdk_nvmf_tcp_transport *ttransport;
855 	struct spdk_nvmf_tcp_port *port;
856 	int trsvcid_int;
857 	uint8_t adrfam;
858 	const char *sock_impl_name;
859 	struct spdk_sock_impl_opts impl_opts;
860 	size_t impl_opts_size = sizeof(impl_opts);
861 	struct spdk_sock_opts opts;
862 
863 	if (!strlen(trid->trsvcid)) {
864 		SPDK_ERRLOG("Service id is required\n");
865 		return -EINVAL;
866 	}
867 
868 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
869 
870 	trsvcid_int = nvmf_tcp_trsvcid_to_int(trid->trsvcid);
871 	if (trsvcid_int < 0) {
872 		SPDK_ERRLOG("Invalid trsvcid '%s'\n", trid->trsvcid);
873 		return -EINVAL;
874 	}
875 
876 	port = calloc(1, sizeof(*port));
877 	if (!port) {
878 		SPDK_ERRLOG("Port allocation failed\n");
879 		return -ENOMEM;
880 	}
881 
882 	port->trid = trid;
883 
884 	sock_impl_name = NULL;
885 
886 	opts.opts_size = sizeof(opts);
887 	spdk_sock_get_default_opts(&opts);
888 	opts.priority = ttransport->tcp_opts.sock_priority;
889 	if (listen_opts->secure_channel) {
890 		sock_impl_name = "ssl";
891 		spdk_sock_impl_get_opts(sock_impl_name, &impl_opts, &impl_opts_size);
892 		impl_opts.tls_version = SPDK_TLS_VERSION_1_3;
893 		impl_opts.get_key = tcp_sock_get_key;
894 		impl_opts.get_key_ctx = ttransport;
895 		opts.impl_opts = &impl_opts;
896 		opts.impl_opts_size = sizeof(impl_opts);
897 	}
898 
899 	port->listen_sock = spdk_sock_listen_ext(trid->traddr, trsvcid_int,
900 			    sock_impl_name, &opts);
901 	if (port->listen_sock == NULL) {
902 		SPDK_ERRLOG("spdk_sock_listen(%s, %d) failed: %s (%d)\n",
903 			    trid->traddr, trsvcid_int,
904 			    spdk_strerror(errno), errno);
905 		free(port);
906 		return -errno;
907 	}
908 
909 	if (spdk_sock_is_ipv4(port->listen_sock)) {
910 		adrfam = SPDK_NVMF_ADRFAM_IPV4;
911 	} else if (spdk_sock_is_ipv6(port->listen_sock)) {
912 		adrfam = SPDK_NVMF_ADRFAM_IPV6;
913 	} else {
914 		SPDK_ERRLOG("Unhandled socket type\n");
915 		adrfam = 0;
916 	}
917 
918 	if (adrfam != trid->adrfam) {
919 		SPDK_ERRLOG("Socket address family mismatch\n");
920 		spdk_sock_close(&port->listen_sock);
921 		free(port);
922 		return -EINVAL;
923 	}
924 
925 	SPDK_NOTICELOG("*** NVMe/TCP Target Listening on %s port %s ***\n",
926 		       trid->traddr, trid->trsvcid);
927 
928 	TAILQ_INSERT_TAIL(&ttransport->ports, port, link);
929 	return 0;
930 }
931 
932 static void
933 nvmf_tcp_stop_listen(struct spdk_nvmf_transport *transport,
934 		     const struct spdk_nvme_transport_id *trid)
935 {
936 	struct spdk_nvmf_tcp_transport *ttransport;
937 	struct spdk_nvmf_tcp_port *port;
938 
939 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
940 
941 	SPDK_DEBUGLOG(nvmf_tcp, "Removing listen address %s port %s\n",
942 		      trid->traddr, trid->trsvcid);
943 
944 	port = nvmf_tcp_find_port(ttransport, trid);
945 	if (port) {
946 		TAILQ_REMOVE(&ttransport->ports, port, link);
947 		spdk_sock_close(&port->listen_sock);
948 		free(port);
949 	}
950 }
951 
952 static void nvmf_tcp_qpair_set_recv_state(struct spdk_nvmf_tcp_qpair *tqpair,
953 		enum nvme_tcp_pdu_recv_state state);
954 
955 static void
956 nvmf_tcp_qpair_set_state(struct spdk_nvmf_tcp_qpair *tqpair, enum nvme_tcp_qpair_state state)
957 {
958 	tqpair->state = state;
959 	spdk_trace_record(TRACE_TCP_QP_STATE_CHANGE, tqpair->qpair.qid, 0, (uintptr_t)tqpair,
960 			  tqpair->state);
961 }
962 
963 static void
964 nvmf_tcp_qpair_disconnect(struct spdk_nvmf_tcp_qpair *tqpair)
965 {
966 	SPDK_DEBUGLOG(nvmf_tcp, "Disconnecting qpair %p\n", tqpair);
967 
968 	spdk_trace_record(TRACE_TCP_QP_DISCONNECT, 0, 0, (uintptr_t)tqpair);
969 
970 	if (tqpair->state <= NVME_TCP_QPAIR_STATE_RUNNING) {
971 		nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_EXITING);
972 		assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_ERROR);
973 		spdk_poller_unregister(&tqpair->timeout_poller);
974 
975 		/* This will end up calling nvmf_tcp_close_qpair */
976 		spdk_nvmf_qpair_disconnect(&tqpair->qpair, NULL, NULL);
977 	}
978 }
979 
980 static void
981 _mgmt_pdu_write_done(void *_tqpair, int err)
982 {
983 	struct spdk_nvmf_tcp_qpair *tqpair = _tqpair;
984 	struct nvme_tcp_pdu *pdu = tqpair->mgmt_pdu;
985 
986 	if (spdk_unlikely(err != 0)) {
987 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_QUIESCING);
988 		return;
989 	}
990 
991 	assert(pdu->cb_fn != NULL);
992 	pdu->cb_fn(pdu->cb_arg);
993 }
994 
995 static void
996 _req_pdu_write_done(void *req, int err)
997 {
998 	struct spdk_nvmf_tcp_req *tcp_req = req;
999 	struct nvme_tcp_pdu *pdu = tcp_req->pdu;
1000 	struct spdk_nvmf_tcp_qpair *tqpair = pdu->qpair;
1001 
1002 	assert(tcp_req->pdu_in_use);
1003 	tcp_req->pdu_in_use = false;
1004 
1005 	/* If the request is in a completed state, we're waiting for write completion to free it */
1006 	if (spdk_unlikely(tcp_req->state == TCP_REQUEST_STATE_COMPLETED)) {
1007 		nvmf_tcp_request_free(tcp_req);
1008 		return;
1009 	}
1010 
1011 	if (spdk_unlikely(err != 0)) {
1012 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_QUIESCING);
1013 		return;
1014 	}
1015 
1016 	assert(pdu->cb_fn != NULL);
1017 	pdu->cb_fn(pdu->cb_arg);
1018 }
1019 
1020 static void
1021 _pdu_write_done(struct nvme_tcp_pdu *pdu, int err)
1022 {
1023 	pdu->sock_req.cb_fn(pdu->sock_req.cb_arg, err);
1024 }
1025 
1026 static void
1027 _tcp_write_pdu(struct nvme_tcp_pdu *pdu)
1028 {
1029 	int rc;
1030 	uint32_t mapped_length;
1031 	struct spdk_nvmf_tcp_qpair *tqpair = pdu->qpair;
1032 
1033 	pdu->sock_req.iovcnt = nvme_tcp_build_iovs(pdu->iov, SPDK_COUNTOF(pdu->iov), pdu,
1034 			       tqpair->host_hdgst_enable, tqpair->host_ddgst_enable, &mapped_length);
1035 	spdk_sock_writev_async(tqpair->sock, &pdu->sock_req);
1036 
1037 	if (pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_RESP ||
1038 	    pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ) {
1039 		/* Try to force the send immediately. */
1040 		rc = spdk_sock_flush(tqpair->sock);
1041 		if (rc > 0 && (uint32_t)rc == mapped_length) {
1042 			_pdu_write_done(pdu, 0);
1043 		} else {
1044 			SPDK_ERRLOG("Could not write %s to socket: rc=%d, errno=%d\n",
1045 				    pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_RESP ?
1046 				    "IC_RESP" : "TERM_REQ", rc, errno);
1047 			_pdu_write_done(pdu, rc >= 0 ? -EAGAIN : -errno);
1048 		}
1049 	}
1050 }
1051 
1052 static void
1053 data_crc32_accel_done(void *cb_arg, int status)
1054 {
1055 	struct nvme_tcp_pdu *pdu = cb_arg;
1056 
1057 	if (spdk_unlikely(status)) {
1058 		SPDK_ERRLOG("Failed to compute the data digest for pdu =%p\n", pdu);
1059 		_pdu_write_done(pdu, status);
1060 		return;
1061 	}
1062 
1063 	pdu->data_digest_crc32 ^= SPDK_CRC32C_XOR;
1064 	MAKE_DIGEST_WORD(pdu->data_digest, pdu->data_digest_crc32);
1065 
1066 	_tcp_write_pdu(pdu);
1067 }
1068 
1069 static void
1070 pdu_data_crc32_compute(struct nvme_tcp_pdu *pdu)
1071 {
1072 	struct spdk_nvmf_tcp_qpair *tqpair = pdu->qpair;
1073 	int rc = 0;
1074 
1075 	/* Data Digest */
1076 	if (pdu->data_len > 0 && g_nvme_tcp_ddgst[pdu->hdr.common.pdu_type] && tqpair->host_ddgst_enable) {
1077 		/* Only support this limitated case for the first step */
1078 		if (spdk_likely(!pdu->dif_ctx && (pdu->data_len % SPDK_NVME_TCP_DIGEST_ALIGNMENT == 0)
1079 				&& tqpair->group)) {
1080 			rc = spdk_accel_submit_crc32cv(tqpair->group->accel_channel, &pdu->data_digest_crc32, pdu->data_iov,
1081 						       pdu->data_iovcnt, 0, data_crc32_accel_done, pdu);
1082 			if (spdk_likely(rc == 0)) {
1083 				return;
1084 			}
1085 		} else {
1086 			pdu->data_digest_crc32 = nvme_tcp_pdu_calc_data_digest(pdu);
1087 		}
1088 		data_crc32_accel_done(pdu, rc);
1089 	} else {
1090 		_tcp_write_pdu(pdu);
1091 	}
1092 }
1093 
1094 static void
1095 nvmf_tcp_qpair_write_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
1096 			 struct nvme_tcp_pdu *pdu,
1097 			 nvme_tcp_qpair_xfer_complete_cb cb_fn,
1098 			 void *cb_arg)
1099 {
1100 	int hlen;
1101 	uint32_t crc32c;
1102 
1103 	assert(tqpair->pdu_in_progress != pdu);
1104 
1105 	hlen = pdu->hdr.common.hlen;
1106 	pdu->cb_fn = cb_fn;
1107 	pdu->cb_arg = cb_arg;
1108 
1109 	pdu->iov[0].iov_base = &pdu->hdr.raw;
1110 	pdu->iov[0].iov_len = hlen;
1111 
1112 	/* Header Digest */
1113 	if (g_nvme_tcp_hdgst[pdu->hdr.common.pdu_type] && tqpair->host_hdgst_enable) {
1114 		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
1115 		MAKE_DIGEST_WORD((uint8_t *)pdu->hdr.raw + hlen, crc32c);
1116 	}
1117 
1118 	/* Data Digest */
1119 	pdu_data_crc32_compute(pdu);
1120 }
1121 
1122 static void
1123 nvmf_tcp_qpair_write_mgmt_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
1124 			      nvme_tcp_qpair_xfer_complete_cb cb_fn,
1125 			      void *cb_arg)
1126 {
1127 	struct nvme_tcp_pdu *pdu = tqpair->mgmt_pdu;
1128 
1129 	pdu->sock_req.cb_fn = _mgmt_pdu_write_done;
1130 	pdu->sock_req.cb_arg = tqpair;
1131 
1132 	nvmf_tcp_qpair_write_pdu(tqpair, pdu, cb_fn, cb_arg);
1133 }
1134 
1135 static void
1136 nvmf_tcp_qpair_write_req_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
1137 			     struct spdk_nvmf_tcp_req *tcp_req,
1138 			     nvme_tcp_qpair_xfer_complete_cb cb_fn,
1139 			     void *cb_arg)
1140 {
1141 	struct nvme_tcp_pdu *pdu = tcp_req->pdu;
1142 
1143 	pdu->sock_req.cb_fn = _req_pdu_write_done;
1144 	pdu->sock_req.cb_arg = tcp_req;
1145 
1146 	assert(!tcp_req->pdu_in_use);
1147 	tcp_req->pdu_in_use = true;
1148 
1149 	nvmf_tcp_qpair_write_pdu(tqpair, pdu, cb_fn, cb_arg);
1150 }
1151 
1152 static int
1153 nvmf_tcp_qpair_init_mem_resource(struct spdk_nvmf_tcp_qpair *tqpair)
1154 {
1155 	uint32_t i;
1156 	struct spdk_nvmf_transport_opts *opts;
1157 	uint32_t in_capsule_data_size;
1158 
1159 	opts = &tqpair->qpair.transport->opts;
1160 
1161 	in_capsule_data_size = opts->in_capsule_data_size;
1162 	if (opts->dif_insert_or_strip) {
1163 		in_capsule_data_size = SPDK_BDEV_BUF_SIZE_WITH_MD(in_capsule_data_size);
1164 	}
1165 
1166 	tqpair->resource_count = opts->max_queue_depth;
1167 
1168 	tqpair->reqs = calloc(tqpair->resource_count, sizeof(*tqpair->reqs));
1169 	if (!tqpair->reqs) {
1170 		SPDK_ERRLOG("Unable to allocate reqs on tqpair=%p\n", tqpair);
1171 		return -1;
1172 	}
1173 
1174 	if (in_capsule_data_size) {
1175 		tqpair->bufs = spdk_zmalloc(tqpair->resource_count * in_capsule_data_size, 0x1000,
1176 					    NULL, SPDK_ENV_LCORE_ID_ANY,
1177 					    SPDK_MALLOC_DMA);
1178 		if (!tqpair->bufs) {
1179 			SPDK_ERRLOG("Unable to allocate bufs on tqpair=%p.\n", tqpair);
1180 			return -1;
1181 		}
1182 	}
1183 	/* prepare memory space for receiving pdus and tcp_req */
1184 	/* Add additional 1 member, which will be used for mgmt_pdu owned by the tqpair */
1185 	tqpair->pdus = spdk_dma_zmalloc((2 * tqpair->resource_count + 1) * sizeof(*tqpair->pdus), 0x1000,
1186 					NULL);
1187 	if (!tqpair->pdus) {
1188 		SPDK_ERRLOG("Unable to allocate pdu pool on tqpair =%p.\n", tqpair);
1189 		return -1;
1190 	}
1191 
1192 	for (i = 0; i < tqpair->resource_count; i++) {
1193 		struct spdk_nvmf_tcp_req *tcp_req = &tqpair->reqs[i];
1194 
1195 		tcp_req->ttag = i + 1;
1196 		tcp_req->req.qpair = &tqpair->qpair;
1197 
1198 		tcp_req->pdu = &tqpair->pdus[i];
1199 		tcp_req->pdu->qpair = tqpair;
1200 
1201 		/* Set up memory to receive commands */
1202 		if (tqpair->bufs) {
1203 			tcp_req->buf = (void *)((uintptr_t)tqpair->bufs + (i * in_capsule_data_size));
1204 		}
1205 
1206 		/* Set the cmdn and rsp */
1207 		tcp_req->req.rsp = (union nvmf_c2h_msg *)&tcp_req->rsp;
1208 		tcp_req->req.cmd = (union nvmf_h2c_msg *)&tcp_req->cmd;
1209 
1210 		tcp_req->req.stripped_data = NULL;
1211 
1212 		/* Initialize request state to FREE */
1213 		tcp_req->state = TCP_REQUEST_STATE_FREE;
1214 		TAILQ_INSERT_TAIL(&tqpair->tcp_req_free_queue, tcp_req, state_link);
1215 		tqpair->state_cntr[TCP_REQUEST_STATE_FREE]++;
1216 	}
1217 
1218 	for (; i < 2 * tqpair->resource_count; i++) {
1219 		struct nvme_tcp_pdu *pdu = &tqpair->pdus[i];
1220 
1221 		pdu->qpair = tqpair;
1222 		SLIST_INSERT_HEAD(&tqpair->tcp_pdu_free_queue, pdu, slist);
1223 	}
1224 
1225 	tqpair->mgmt_pdu = &tqpair->pdus[i];
1226 	tqpair->mgmt_pdu->qpair = tqpair;
1227 	tqpair->pdu_in_progress = SLIST_FIRST(&tqpair->tcp_pdu_free_queue);
1228 	SLIST_REMOVE_HEAD(&tqpair->tcp_pdu_free_queue, slist);
1229 	tqpair->tcp_pdu_working_count = 1;
1230 
1231 	tqpair->recv_buf_size = (in_capsule_data_size + sizeof(struct spdk_nvme_tcp_cmd) + 2 *
1232 				 SPDK_NVME_TCP_DIGEST_LEN) * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
1233 
1234 	return 0;
1235 }
1236 
1237 static int
1238 nvmf_tcp_qpair_init(struct spdk_nvmf_qpair *qpair)
1239 {
1240 	struct spdk_nvmf_tcp_qpair *tqpair;
1241 
1242 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
1243 
1244 	SPDK_DEBUGLOG(nvmf_tcp, "New TCP Connection: %p\n", qpair);
1245 
1246 	spdk_trace_record(TRACE_TCP_QP_CREATE, 0, 0, (uintptr_t)tqpair);
1247 
1248 	/* Initialise request state queues of the qpair */
1249 	TAILQ_INIT(&tqpair->tcp_req_free_queue);
1250 	TAILQ_INIT(&tqpair->tcp_req_working_queue);
1251 	SLIST_INIT(&tqpair->tcp_pdu_free_queue);
1252 
1253 	tqpair->host_hdgst_enable = true;
1254 	tqpair->host_ddgst_enable = true;
1255 
1256 	return 0;
1257 }
1258 
1259 static int
1260 nvmf_tcp_qpair_sock_init(struct spdk_nvmf_tcp_qpair *tqpair)
1261 {
1262 	int rc;
1263 
1264 	spdk_trace_record(TRACE_TCP_QP_SOCK_INIT, 0, 0, (uintptr_t)tqpair);
1265 
1266 	/* set low water mark */
1267 	rc = spdk_sock_set_recvlowat(tqpair->sock, 1);
1268 	if (rc != 0) {
1269 		SPDK_ERRLOG("spdk_sock_set_recvlowat() failed\n");
1270 		return rc;
1271 	}
1272 
1273 	return 0;
1274 }
1275 
1276 static void
1277 nvmf_tcp_handle_connect(struct spdk_nvmf_transport *transport,
1278 			struct spdk_nvmf_tcp_port *port,
1279 			struct spdk_sock *sock)
1280 {
1281 	struct spdk_nvmf_tcp_qpair *tqpair;
1282 	int rc;
1283 
1284 	SPDK_DEBUGLOG(nvmf_tcp, "New connection accepted on %s port %s\n",
1285 		      port->trid->traddr, port->trid->trsvcid);
1286 
1287 	tqpair = calloc(1, sizeof(struct spdk_nvmf_tcp_qpair));
1288 	if (tqpair == NULL) {
1289 		SPDK_ERRLOG("Could not allocate new connection.\n");
1290 		spdk_sock_close(&sock);
1291 		return;
1292 	}
1293 
1294 	tqpair->sock = sock;
1295 	tqpair->state_cntr[TCP_REQUEST_STATE_FREE] = 0;
1296 	tqpair->port = port;
1297 	tqpair->qpair.transport = transport;
1298 
1299 	rc = spdk_sock_getaddr(tqpair->sock, tqpair->target_addr,
1300 			       sizeof(tqpair->target_addr), &tqpair->target_port,
1301 			       tqpair->initiator_addr, sizeof(tqpair->initiator_addr),
1302 			       &tqpair->initiator_port);
1303 	if (rc < 0) {
1304 		SPDK_ERRLOG("spdk_sock_getaddr() failed of tqpair=%p\n", tqpair);
1305 		nvmf_tcp_qpair_destroy(tqpair);
1306 		return;
1307 	}
1308 
1309 	spdk_nvmf_tgt_new_qpair(transport->tgt, &tqpair->qpair);
1310 }
1311 
1312 static uint32_t
1313 nvmf_tcp_port_accept(struct spdk_nvmf_transport *transport, struct spdk_nvmf_tcp_port *port)
1314 {
1315 	struct spdk_sock *sock;
1316 	uint32_t count = 0;
1317 	int i;
1318 
1319 	for (i = 0; i < NVMF_TCP_MAX_ACCEPT_SOCK_ONE_TIME; i++) {
1320 		sock = spdk_sock_accept(port->listen_sock);
1321 		if (sock == NULL) {
1322 			break;
1323 		}
1324 		count++;
1325 		nvmf_tcp_handle_connect(transport, port, sock);
1326 	}
1327 
1328 	return count;
1329 }
1330 
1331 static int
1332 nvmf_tcp_accept(void *ctx)
1333 {
1334 	struct spdk_nvmf_transport *transport = ctx;
1335 	struct spdk_nvmf_tcp_transport *ttransport;
1336 	struct spdk_nvmf_tcp_port *port;
1337 	uint32_t count = 0;
1338 
1339 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
1340 
1341 	TAILQ_FOREACH(port, &ttransport->ports, link) {
1342 		count += nvmf_tcp_port_accept(transport, port);
1343 	}
1344 
1345 	return count > 0 ? SPDK_POLLER_BUSY : SPDK_POLLER_IDLE;
1346 }
1347 
1348 static void
1349 nvmf_tcp_discover(struct spdk_nvmf_transport *transport,
1350 		  struct spdk_nvme_transport_id *trid,
1351 		  struct spdk_nvmf_discovery_log_page_entry *entry)
1352 {
1353 	entry->trtype = SPDK_NVMF_TRTYPE_TCP;
1354 	entry->adrfam = trid->adrfam;
1355 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
1356 
1357 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
1358 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
1359 
1360 	entry->tsas.tcp.sectype = SPDK_NVME_TCP_SECURITY_NONE;
1361 }
1362 
1363 static struct spdk_nvmf_tcp_control_msg_list *
1364 nvmf_tcp_control_msg_list_create(uint16_t num_messages)
1365 {
1366 	struct spdk_nvmf_tcp_control_msg_list *list;
1367 	struct spdk_nvmf_tcp_control_msg *msg;
1368 	uint16_t i;
1369 
1370 	list = calloc(1, sizeof(*list));
1371 	if (!list) {
1372 		SPDK_ERRLOG("Failed to allocate memory for list structure\n");
1373 		return NULL;
1374 	}
1375 
1376 	list->msg_buf = spdk_zmalloc(num_messages * SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE,
1377 				     NVMF_DATA_BUFFER_ALIGNMENT, NULL, SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
1378 	if (!list->msg_buf) {
1379 		SPDK_ERRLOG("Failed to allocate memory for control message buffers\n");
1380 		free(list);
1381 		return NULL;
1382 	}
1383 
1384 	STAILQ_INIT(&list->free_msgs);
1385 
1386 	for (i = 0; i < num_messages; i++) {
1387 		msg = (struct spdk_nvmf_tcp_control_msg *)((char *)list->msg_buf + i *
1388 				SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE);
1389 		STAILQ_INSERT_TAIL(&list->free_msgs, msg, link);
1390 	}
1391 
1392 	return list;
1393 }
1394 
1395 static void
1396 nvmf_tcp_control_msg_list_free(struct spdk_nvmf_tcp_control_msg_list *list)
1397 {
1398 	if (!list) {
1399 		return;
1400 	}
1401 
1402 	spdk_free(list->msg_buf);
1403 	free(list);
1404 }
1405 
1406 static struct spdk_nvmf_transport_poll_group *
1407 nvmf_tcp_poll_group_create(struct spdk_nvmf_transport *transport,
1408 			   struct spdk_nvmf_poll_group *group)
1409 {
1410 	struct spdk_nvmf_tcp_transport	*ttransport;
1411 	struct spdk_nvmf_tcp_poll_group *tgroup;
1412 
1413 	tgroup = calloc(1, sizeof(*tgroup));
1414 	if (!tgroup) {
1415 		return NULL;
1416 	}
1417 
1418 	tgroup->sock_group = spdk_sock_group_create(&tgroup->group);
1419 	if (!tgroup->sock_group) {
1420 		goto cleanup;
1421 	}
1422 
1423 	TAILQ_INIT(&tgroup->qpairs);
1424 	TAILQ_INIT(&tgroup->await_req);
1425 
1426 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
1427 
1428 	if (transport->opts.in_capsule_data_size < SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE) {
1429 		SPDK_DEBUGLOG(nvmf_tcp, "ICD %u is less than min required for admin/fabric commands (%u). "
1430 			      "Creating control messages list\n", transport->opts.in_capsule_data_size,
1431 			      SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE);
1432 		tgroup->control_msg_list = nvmf_tcp_control_msg_list_create(ttransport->tcp_opts.control_msg_num);
1433 		if (!tgroup->control_msg_list) {
1434 			goto cleanup;
1435 		}
1436 	}
1437 
1438 	tgroup->accel_channel = spdk_accel_get_io_channel();
1439 	if (spdk_unlikely(!tgroup->accel_channel)) {
1440 		SPDK_ERRLOG("Cannot create accel_channel for tgroup=%p\n", tgroup);
1441 		goto cleanup;
1442 	}
1443 
1444 	TAILQ_INSERT_TAIL(&ttransport->poll_groups, tgroup, link);
1445 	if (ttransport->next_pg == NULL) {
1446 		ttransport->next_pg = tgroup;
1447 	}
1448 
1449 	return &tgroup->group;
1450 
1451 cleanup:
1452 	nvmf_tcp_poll_group_destroy(&tgroup->group);
1453 	return NULL;
1454 }
1455 
1456 static struct spdk_nvmf_transport_poll_group *
1457 nvmf_tcp_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
1458 {
1459 	struct spdk_nvmf_tcp_transport *ttransport;
1460 	struct spdk_nvmf_tcp_poll_group **pg;
1461 	struct spdk_nvmf_tcp_qpair *tqpair;
1462 	struct spdk_sock_group *group = NULL, *hint = NULL;
1463 	int rc;
1464 
1465 	ttransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_tcp_transport, transport);
1466 
1467 	if (TAILQ_EMPTY(&ttransport->poll_groups)) {
1468 		return NULL;
1469 	}
1470 
1471 	pg = &ttransport->next_pg;
1472 	assert(*pg != NULL);
1473 	hint = (*pg)->sock_group;
1474 
1475 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
1476 	rc = spdk_sock_get_optimal_sock_group(tqpair->sock, &group, hint);
1477 	if (rc != 0) {
1478 		return NULL;
1479 	} else if (group != NULL) {
1480 		/* Optimal poll group was found */
1481 		return spdk_sock_group_get_ctx(group);
1482 	}
1483 
1484 	/* The hint was used for optimal poll group, advance next_pg. */
1485 	*pg = TAILQ_NEXT(*pg, link);
1486 	if (*pg == NULL) {
1487 		*pg = TAILQ_FIRST(&ttransport->poll_groups);
1488 	}
1489 
1490 	return spdk_sock_group_get_ctx(hint);
1491 }
1492 
1493 static void
1494 nvmf_tcp_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
1495 {
1496 	struct spdk_nvmf_tcp_poll_group *tgroup, *next_tgroup;
1497 	struct spdk_nvmf_tcp_transport *ttransport;
1498 
1499 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
1500 	spdk_sock_group_close(&tgroup->sock_group);
1501 	if (tgroup->control_msg_list) {
1502 		nvmf_tcp_control_msg_list_free(tgroup->control_msg_list);
1503 	}
1504 
1505 	if (tgroup->accel_channel) {
1506 		spdk_put_io_channel(tgroup->accel_channel);
1507 	}
1508 
1509 	ttransport = SPDK_CONTAINEROF(tgroup->group.transport, struct spdk_nvmf_tcp_transport, transport);
1510 
1511 	next_tgroup = TAILQ_NEXT(tgroup, link);
1512 	TAILQ_REMOVE(&ttransport->poll_groups, tgroup, link);
1513 	if (next_tgroup == NULL) {
1514 		next_tgroup = TAILQ_FIRST(&ttransport->poll_groups);
1515 	}
1516 	if (ttransport->next_pg == tgroup) {
1517 		ttransport->next_pg = next_tgroup;
1518 	}
1519 
1520 	free(tgroup);
1521 }
1522 
1523 static void
1524 nvmf_tcp_qpair_set_recv_state(struct spdk_nvmf_tcp_qpair *tqpair,
1525 			      enum nvme_tcp_pdu_recv_state state)
1526 {
1527 	if (tqpair->recv_state == state) {
1528 		SPDK_ERRLOG("The recv state of tqpair=%p is same with the state(%d) to be set\n",
1529 			    tqpair, state);
1530 		return;
1531 	}
1532 
1533 	if (spdk_unlikely(state == NVME_TCP_PDU_RECV_STATE_QUIESCING)) {
1534 		if (tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH && tqpair->pdu_in_progress) {
1535 			SLIST_INSERT_HEAD(&tqpair->tcp_pdu_free_queue, tqpair->pdu_in_progress, slist);
1536 			tqpair->tcp_pdu_working_count--;
1537 		}
1538 	}
1539 
1540 	if (spdk_unlikely(state == NVME_TCP_PDU_RECV_STATE_ERROR)) {
1541 		assert(tqpair->tcp_pdu_working_count == 0);
1542 	}
1543 
1544 	if (tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_REQ) {
1545 		/* When leaving the await req state, move the qpair to the main list */
1546 		TAILQ_REMOVE(&tqpair->group->await_req, tqpair, link);
1547 		TAILQ_INSERT_TAIL(&tqpair->group->qpairs, tqpair, link);
1548 	} else if (state == NVME_TCP_PDU_RECV_STATE_AWAIT_REQ) {
1549 		TAILQ_REMOVE(&tqpair->group->qpairs, tqpair, link);
1550 		TAILQ_INSERT_TAIL(&tqpair->group->await_req, tqpair, link);
1551 	}
1552 
1553 	SPDK_DEBUGLOG(nvmf_tcp, "tqpair(%p) recv state=%d\n", tqpair, state);
1554 	tqpair->recv_state = state;
1555 
1556 	spdk_trace_record(TRACE_TCP_QP_RCV_STATE_CHANGE, tqpair->qpair.qid, 0, (uintptr_t)tqpair,
1557 			  tqpair->recv_state);
1558 }
1559 
1560 static int
1561 nvmf_tcp_qpair_handle_timeout(void *ctx)
1562 {
1563 	struct spdk_nvmf_tcp_qpair *tqpair = ctx;
1564 
1565 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_ERROR);
1566 
1567 	SPDK_ERRLOG("No pdu coming for tqpair=%p within %d seconds\n", tqpair,
1568 		    SPDK_NVME_TCP_QPAIR_EXIT_TIMEOUT);
1569 
1570 	nvmf_tcp_qpair_disconnect(tqpair);
1571 	return SPDK_POLLER_BUSY;
1572 }
1573 
1574 static void
1575 nvmf_tcp_send_c2h_term_req_complete(void *cb_arg)
1576 {
1577 	struct spdk_nvmf_tcp_qpair *tqpair = (struct spdk_nvmf_tcp_qpair *)cb_arg;
1578 
1579 	if (!tqpair->timeout_poller) {
1580 		tqpair->timeout_poller = SPDK_POLLER_REGISTER(nvmf_tcp_qpair_handle_timeout, tqpair,
1581 					 SPDK_NVME_TCP_QPAIR_EXIT_TIMEOUT * 1000000);
1582 	}
1583 }
1584 
1585 static void
1586 nvmf_tcp_send_c2h_term_req(struct spdk_nvmf_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu,
1587 			   enum spdk_nvme_tcp_term_req_fes fes, uint32_t error_offset)
1588 {
1589 	struct nvme_tcp_pdu *rsp_pdu;
1590 	struct spdk_nvme_tcp_term_req_hdr *c2h_term_req;
1591 	uint32_t c2h_term_req_hdr_len = sizeof(*c2h_term_req);
1592 	uint32_t copy_len;
1593 
1594 	rsp_pdu = tqpair->mgmt_pdu;
1595 
1596 	c2h_term_req = &rsp_pdu->hdr.term_req;
1597 	c2h_term_req->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ;
1598 	c2h_term_req->common.hlen = c2h_term_req_hdr_len;
1599 	c2h_term_req->fes = fes;
1600 
1601 	if ((fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
1602 	    (fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
1603 		DSET32(&c2h_term_req->fei, error_offset);
1604 	}
1605 
1606 	copy_len = spdk_min(pdu->hdr.common.hlen, SPDK_NVME_TCP_TERM_REQ_ERROR_DATA_MAX_SIZE);
1607 
1608 	/* Copy the error info into the buffer */
1609 	memcpy((uint8_t *)rsp_pdu->hdr.raw + c2h_term_req_hdr_len, pdu->hdr.raw, copy_len);
1610 	nvme_tcp_pdu_set_data(rsp_pdu, (uint8_t *)rsp_pdu->hdr.raw + c2h_term_req_hdr_len, copy_len);
1611 
1612 	/* Contain the header of the wrong received pdu */
1613 	c2h_term_req->common.plen = c2h_term_req->common.hlen + copy_len;
1614 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_QUIESCING);
1615 	nvmf_tcp_qpair_write_mgmt_pdu(tqpair, nvmf_tcp_send_c2h_term_req_complete, tqpair);
1616 }
1617 
1618 static void
1619 nvmf_tcp_capsule_cmd_hdr_handle(struct spdk_nvmf_tcp_transport *ttransport,
1620 				struct spdk_nvmf_tcp_qpair *tqpair,
1621 				struct nvme_tcp_pdu *pdu)
1622 {
1623 	struct spdk_nvmf_tcp_req *tcp_req;
1624 
1625 	assert(pdu->psh_valid_bytes == pdu->psh_len);
1626 	assert(pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD);
1627 
1628 	tcp_req = nvmf_tcp_req_get(tqpair);
1629 	if (!tcp_req) {
1630 		/* Directly return and make the allocation retry again.  This can happen if we're
1631 		 * using asynchronous writes to send the response to the host or when releasing
1632 		 * zero-copy buffers after a response has been sent.  In both cases, the host might
1633 		 * receive the response before we've finished processing the request and is free to
1634 		 * send another one.
1635 		 */
1636 		if (tqpair->state_cntr[TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST] > 0 ||
1637 		    tqpair->state_cntr[TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE] > 0) {
1638 			return;
1639 		}
1640 
1641 		/* The host sent more commands than the maximum queue depth. */
1642 		SPDK_ERRLOG("Cannot allocate tcp_req on tqpair=%p\n", tqpair);
1643 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_QUIESCING);
1644 		return;
1645 	}
1646 
1647 	pdu->req = tcp_req;
1648 	assert(tcp_req->state == TCP_REQUEST_STATE_NEW);
1649 	nvmf_tcp_req_process(ttransport, tcp_req);
1650 }
1651 
1652 static void
1653 nvmf_tcp_capsule_cmd_payload_handle(struct spdk_nvmf_tcp_transport *ttransport,
1654 				    struct spdk_nvmf_tcp_qpair *tqpair,
1655 				    struct nvme_tcp_pdu *pdu)
1656 {
1657 	struct spdk_nvmf_tcp_req *tcp_req;
1658 	struct spdk_nvme_tcp_cmd *capsule_cmd;
1659 	uint32_t error_offset = 0;
1660 	enum spdk_nvme_tcp_term_req_fes fes;
1661 	struct spdk_nvme_cpl *rsp;
1662 
1663 	capsule_cmd = &pdu->hdr.capsule_cmd;
1664 	tcp_req = pdu->req;
1665 	assert(tcp_req != NULL);
1666 
1667 	/* Zero-copy requests don't support ICD */
1668 	assert(!spdk_nvmf_request_using_zcopy(&tcp_req->req));
1669 
1670 	if (capsule_cmd->common.pdo > SPDK_NVME_TCP_PDU_PDO_MAX_OFFSET) {
1671 		SPDK_ERRLOG("Expected ICReq capsule_cmd pdu offset <= %d, got %c\n",
1672 			    SPDK_NVME_TCP_PDU_PDO_MAX_OFFSET, capsule_cmd->common.pdo);
1673 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1674 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdo);
1675 		goto err;
1676 	}
1677 
1678 	rsp = &tcp_req->req.rsp->nvme_cpl;
1679 	if (spdk_unlikely(rsp->status.sc == SPDK_NVME_SC_COMMAND_TRANSIENT_TRANSPORT_ERROR)) {
1680 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
1681 	} else {
1682 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1683 	}
1684 
1685 	nvmf_tcp_req_process(ttransport, tcp_req);
1686 
1687 	return;
1688 err:
1689 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1690 }
1691 
1692 static void
1693 nvmf_tcp_h2c_data_hdr_handle(struct spdk_nvmf_tcp_transport *ttransport,
1694 			     struct spdk_nvmf_tcp_qpair *tqpair,
1695 			     struct nvme_tcp_pdu *pdu)
1696 {
1697 	struct spdk_nvmf_tcp_req *tcp_req;
1698 	uint32_t error_offset = 0;
1699 	enum spdk_nvme_tcp_term_req_fes fes = 0;
1700 	struct spdk_nvme_tcp_h2c_data_hdr *h2c_data;
1701 
1702 	h2c_data = &pdu->hdr.h2c_data;
1703 
1704 	SPDK_DEBUGLOG(nvmf_tcp, "tqpair=%p, r2t_info: datao=%u, datal=%u, cccid=%u, ttag=%u\n",
1705 		      tqpair, h2c_data->datao, h2c_data->datal, h2c_data->cccid, h2c_data->ttag);
1706 
1707 	if (h2c_data->ttag > tqpair->resource_count) {
1708 		SPDK_DEBUGLOG(nvmf_tcp, "ttag %u is larger than allowed %u.\n", h2c_data->ttag,
1709 			      tqpair->resource_count);
1710 		fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
1711 		error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, ttag);
1712 		goto err;
1713 	}
1714 
1715 	tcp_req = &tqpair->reqs[h2c_data->ttag - 1];
1716 
1717 	if (spdk_unlikely(tcp_req->state != TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER &&
1718 			  tcp_req->state != TCP_REQUEST_STATE_AWAITING_R2T_ACK)) {
1719 		SPDK_DEBUGLOG(nvmf_tcp, "tcp_req(%p), tqpair=%p, has error state in %d\n", tcp_req, tqpair,
1720 			      tcp_req->state);
1721 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1722 		error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, ttag);
1723 		goto err;
1724 	}
1725 
1726 	if (spdk_unlikely(tcp_req->req.cmd->nvme_cmd.cid != h2c_data->cccid)) {
1727 		SPDK_DEBUGLOG(nvmf_tcp, "tcp_req(%p), tqpair=%p, expected %u but %u for cccid.\n", tcp_req, tqpair,
1728 			      tcp_req->req.cmd->nvme_cmd.cid, h2c_data->cccid);
1729 		fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
1730 		error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, cccid);
1731 		goto err;
1732 	}
1733 
1734 	if (tcp_req->h2c_offset != h2c_data->datao) {
1735 		SPDK_DEBUGLOG(nvmf_tcp,
1736 			      "tcp_req(%p), tqpair=%p, expected data offset %u, but data offset is %u\n",
1737 			      tcp_req, tqpair, tcp_req->h2c_offset, h2c_data->datao);
1738 		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
1739 		goto err;
1740 	}
1741 
1742 	if ((h2c_data->datao + h2c_data->datal) > tcp_req->req.length) {
1743 		SPDK_DEBUGLOG(nvmf_tcp,
1744 			      "tcp_req(%p), tqpair=%p,  (datao=%u + datal=%u) exceeds requested length=%u\n",
1745 			      tcp_req, tqpair, h2c_data->datao, h2c_data->datal, tcp_req->req.length);
1746 		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
1747 		goto err;
1748 	}
1749 
1750 	pdu->req = tcp_req;
1751 
1752 	if (spdk_unlikely(tcp_req->req.dif_enabled)) {
1753 		pdu->dif_ctx = &tcp_req->req.dif.dif_ctx;
1754 	}
1755 
1756 	nvme_tcp_pdu_set_data_buf(pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
1757 				  h2c_data->datao, h2c_data->datal);
1758 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1759 	return;
1760 
1761 err:
1762 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1763 }
1764 
1765 static void
1766 nvmf_tcp_send_capsule_resp_pdu(struct spdk_nvmf_tcp_req *tcp_req,
1767 			       struct spdk_nvmf_tcp_qpair *tqpair)
1768 {
1769 	struct nvme_tcp_pdu *rsp_pdu;
1770 	struct spdk_nvme_tcp_rsp *capsule_resp;
1771 
1772 	SPDK_DEBUGLOG(nvmf_tcp, "enter, tqpair=%p\n", tqpair);
1773 
1774 	rsp_pdu = nvmf_tcp_req_pdu_init(tcp_req);
1775 	assert(rsp_pdu != NULL);
1776 
1777 	capsule_resp = &rsp_pdu->hdr.capsule_resp;
1778 	capsule_resp->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_CAPSULE_RESP;
1779 	capsule_resp->common.plen = capsule_resp->common.hlen = sizeof(*capsule_resp);
1780 	capsule_resp->rccqe = tcp_req->req.rsp->nvme_cpl;
1781 	if (tqpair->host_hdgst_enable) {
1782 		capsule_resp->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
1783 		capsule_resp->common.plen += SPDK_NVME_TCP_DIGEST_LEN;
1784 	}
1785 
1786 	nvmf_tcp_qpair_write_req_pdu(tqpair, tcp_req, nvmf_tcp_request_free, tcp_req);
1787 }
1788 
1789 static void
1790 nvmf_tcp_pdu_c2h_data_complete(void *cb_arg)
1791 {
1792 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
1793 	struct spdk_nvmf_tcp_qpair *tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair,
1794 					     struct spdk_nvmf_tcp_qpair, qpair);
1795 
1796 	assert(tqpair != NULL);
1797 
1798 	if (spdk_unlikely(tcp_req->pdu->rw_offset < tcp_req->req.length)) {
1799 		SPDK_DEBUGLOG(nvmf_tcp, "sending another C2H part, offset %u length %u\n", tcp_req->pdu->rw_offset,
1800 			      tcp_req->req.length);
1801 		_nvmf_tcp_send_c2h_data(tqpair, tcp_req);
1802 		return;
1803 	}
1804 
1805 	if (tcp_req->pdu->hdr.c2h_data.common.flags & SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS) {
1806 		nvmf_tcp_request_free(tcp_req);
1807 	} else {
1808 		nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
1809 	}
1810 }
1811 
1812 static void
1813 nvmf_tcp_r2t_complete(void *cb_arg)
1814 {
1815 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
1816 	struct spdk_nvmf_tcp_transport *ttransport;
1817 
1818 	ttransport = SPDK_CONTAINEROF(tcp_req->req.qpair->transport,
1819 				      struct spdk_nvmf_tcp_transport, transport);
1820 
1821 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
1822 
1823 	if (tcp_req->h2c_offset == tcp_req->req.length) {
1824 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1825 		nvmf_tcp_req_process(ttransport, tcp_req);
1826 	}
1827 }
1828 
1829 static void
1830 nvmf_tcp_send_r2t_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
1831 		      struct spdk_nvmf_tcp_req *tcp_req)
1832 {
1833 	struct nvme_tcp_pdu *rsp_pdu;
1834 	struct spdk_nvme_tcp_r2t_hdr *r2t;
1835 
1836 	rsp_pdu = nvmf_tcp_req_pdu_init(tcp_req);
1837 	assert(rsp_pdu != NULL);
1838 
1839 	r2t = &rsp_pdu->hdr.r2t;
1840 	r2t->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_R2T;
1841 	r2t->common.plen = r2t->common.hlen = sizeof(*r2t);
1842 
1843 	if (tqpair->host_hdgst_enable) {
1844 		r2t->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
1845 		r2t->common.plen += SPDK_NVME_TCP_DIGEST_LEN;
1846 	}
1847 
1848 	r2t->cccid = tcp_req->req.cmd->nvme_cmd.cid;
1849 	r2t->ttag = tcp_req->ttag;
1850 	r2t->r2to = tcp_req->h2c_offset;
1851 	r2t->r2tl = tcp_req->req.length;
1852 
1853 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_R2T_ACK);
1854 
1855 	SPDK_DEBUGLOG(nvmf_tcp,
1856 		      "tcp_req(%p) on tqpair(%p), r2t_info: cccid=%u, ttag=%u, r2to=%u, r2tl=%u\n",
1857 		      tcp_req, tqpair, r2t->cccid, r2t->ttag, r2t->r2to, r2t->r2tl);
1858 	nvmf_tcp_qpair_write_req_pdu(tqpair, tcp_req, nvmf_tcp_r2t_complete, tcp_req);
1859 }
1860 
1861 static void
1862 nvmf_tcp_h2c_data_payload_handle(struct spdk_nvmf_tcp_transport *ttransport,
1863 				 struct spdk_nvmf_tcp_qpair *tqpair,
1864 				 struct nvme_tcp_pdu *pdu)
1865 {
1866 	struct spdk_nvmf_tcp_req *tcp_req;
1867 	struct spdk_nvme_cpl *rsp;
1868 
1869 	tcp_req = pdu->req;
1870 	assert(tcp_req != NULL);
1871 
1872 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
1873 
1874 	tcp_req->h2c_offset += pdu->data_len;
1875 
1876 	/* Wait for all of the data to arrive AND for the initial R2T PDU send to be
1877 	 * acknowledged before moving on. */
1878 	if (tcp_req->h2c_offset == tcp_req->req.length &&
1879 	    tcp_req->state == TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER) {
1880 		/* After receiving all the h2c data, we need to check whether there is
1881 		 * transient transport error */
1882 		rsp = &tcp_req->req.rsp->nvme_cpl;
1883 		if (spdk_unlikely(rsp->status.sc == SPDK_NVME_SC_COMMAND_TRANSIENT_TRANSPORT_ERROR)) {
1884 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
1885 		} else {
1886 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1887 		}
1888 		nvmf_tcp_req_process(ttransport, tcp_req);
1889 	}
1890 }
1891 
1892 static void
1893 nvmf_tcp_h2c_term_req_dump(struct spdk_nvme_tcp_term_req_hdr *h2c_term_req)
1894 {
1895 	SPDK_ERRLOG("Error info of pdu(%p): %s\n", h2c_term_req,
1896 		    spdk_nvmf_tcp_term_req_fes_str[h2c_term_req->fes]);
1897 	if ((h2c_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
1898 	    (h2c_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
1899 		SPDK_DEBUGLOG(nvmf_tcp, "The offset from the start of the PDU header is %u\n",
1900 			      DGET32(h2c_term_req->fei));
1901 	}
1902 }
1903 
1904 static void
1905 nvmf_tcp_h2c_term_req_hdr_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1906 				 struct nvme_tcp_pdu *pdu)
1907 {
1908 	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req = &pdu->hdr.term_req;
1909 	uint32_t error_offset = 0;
1910 	enum spdk_nvme_tcp_term_req_fes fes;
1911 
1912 	if (h2c_term_req->fes > SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER) {
1913 		SPDK_ERRLOG("Fatal Error Status(FES) is unknown for h2c_term_req pdu=%p\n", pdu);
1914 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1915 		error_offset = offsetof(struct spdk_nvme_tcp_term_req_hdr, fes);
1916 		goto end;
1917 	}
1918 
1919 	/* set the data buffer */
1920 	nvme_tcp_pdu_set_data(pdu, (uint8_t *)pdu->hdr.raw + h2c_term_req->common.hlen,
1921 			      h2c_term_req->common.plen - h2c_term_req->common.hlen);
1922 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1923 	return;
1924 end:
1925 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1926 }
1927 
1928 static void
1929 nvmf_tcp_h2c_term_req_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1930 				     struct nvme_tcp_pdu *pdu)
1931 {
1932 	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req = &pdu->hdr.term_req;
1933 
1934 	nvmf_tcp_h2c_term_req_dump(h2c_term_req);
1935 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_QUIESCING);
1936 }
1937 
1938 static void
1939 _nvmf_tcp_pdu_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu)
1940 {
1941 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport,
1942 			struct spdk_nvmf_tcp_transport, transport);
1943 
1944 	switch (pdu->hdr.common.pdu_type) {
1945 	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
1946 		nvmf_tcp_capsule_cmd_payload_handle(ttransport, tqpair, pdu);
1947 		break;
1948 	case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
1949 		nvmf_tcp_h2c_data_payload_handle(ttransport, tqpair, pdu);
1950 		break;
1951 
1952 	case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
1953 		nvmf_tcp_h2c_term_req_payload_handle(tqpair, pdu);
1954 		break;
1955 
1956 	default:
1957 		/* The code should not go to here */
1958 		SPDK_ERRLOG("ERROR pdu type %d\n", pdu->hdr.common.pdu_type);
1959 		break;
1960 	}
1961 	SLIST_INSERT_HEAD(&tqpair->tcp_pdu_free_queue, pdu, slist);
1962 	tqpair->tcp_pdu_working_count--;
1963 }
1964 
1965 static void
1966 data_crc32_calc_done(void *cb_arg, int status)
1967 {
1968 	struct nvme_tcp_pdu *pdu = cb_arg;
1969 	struct spdk_nvmf_tcp_qpair *tqpair = pdu->qpair;
1970 	struct spdk_nvmf_tcp_req *tcp_req;
1971 	struct spdk_nvme_cpl *rsp;
1972 
1973 	/* async crc32 calculation is failed and use direct calculation to check */
1974 	if (spdk_unlikely(status)) {
1975 		SPDK_ERRLOG("Data digest on tqpair=(%p) with pdu=%p failed to be calculated asynchronously\n",
1976 			    tqpair, pdu);
1977 		pdu->data_digest_crc32 = nvme_tcp_pdu_calc_data_digest(pdu);
1978 	}
1979 	pdu->data_digest_crc32 ^= SPDK_CRC32C_XOR;
1980 	if (!MATCH_DIGEST_WORD(pdu->data_digest, pdu->data_digest_crc32)) {
1981 		SPDK_ERRLOG("Data digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
1982 		tcp_req = pdu->req;
1983 		assert(tcp_req != NULL);
1984 		rsp = &tcp_req->req.rsp->nvme_cpl;
1985 		rsp->status.sc = SPDK_NVME_SC_COMMAND_TRANSIENT_TRANSPORT_ERROR;
1986 	}
1987 	_nvmf_tcp_pdu_payload_handle(tqpair, pdu);
1988 }
1989 
1990 static void
1991 nvmf_tcp_pdu_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu)
1992 {
1993 	int rc = 0;
1994 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1995 	tqpair->pdu_in_progress = NULL;
1996 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1997 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
1998 	/* check data digest if need */
1999 	if (pdu->ddgst_enable) {
2000 		if (tqpair->qpair.qid != 0 && !pdu->dif_ctx && tqpair->group &&
2001 		    (pdu->data_len % SPDK_NVME_TCP_DIGEST_ALIGNMENT == 0)) {
2002 			rc = spdk_accel_submit_crc32cv(tqpair->group->accel_channel, &pdu->data_digest_crc32, pdu->data_iov,
2003 						       pdu->data_iovcnt, 0, data_crc32_calc_done, pdu);
2004 			if (spdk_likely(rc == 0)) {
2005 				return;
2006 			}
2007 		} else {
2008 			pdu->data_digest_crc32 = nvme_tcp_pdu_calc_data_digest(pdu);
2009 		}
2010 		data_crc32_calc_done(pdu, rc);
2011 	} else {
2012 		_nvmf_tcp_pdu_payload_handle(tqpair, pdu);
2013 	}
2014 }
2015 
2016 static void
2017 nvmf_tcp_send_icresp_complete(void *cb_arg)
2018 {
2019 	struct spdk_nvmf_tcp_qpair *tqpair = cb_arg;
2020 
2021 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_RUNNING);
2022 }
2023 
2024 static void
2025 nvmf_tcp_icreq_handle(struct spdk_nvmf_tcp_transport *ttransport,
2026 		      struct spdk_nvmf_tcp_qpair *tqpair,
2027 		      struct nvme_tcp_pdu *pdu)
2028 {
2029 	struct spdk_nvme_tcp_ic_req *ic_req = &pdu->hdr.ic_req;
2030 	struct nvme_tcp_pdu *rsp_pdu;
2031 	struct spdk_nvme_tcp_ic_resp *ic_resp;
2032 	uint32_t error_offset = 0;
2033 	enum spdk_nvme_tcp_term_req_fes fes;
2034 
2035 	/* Only PFV 0 is defined currently */
2036 	if (ic_req->pfv != 0) {
2037 		SPDK_ERRLOG("Expected ICReq PFV %u, got %u\n", 0u, ic_req->pfv);
2038 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2039 		error_offset = offsetof(struct spdk_nvme_tcp_ic_req, pfv);
2040 		goto end;
2041 	}
2042 
2043 	/* This value is 0’s based value in units of dwords should not be larger than SPDK_NVME_TCP_HPDA_MAX */
2044 	if (ic_req->hpda > SPDK_NVME_TCP_HPDA_MAX) {
2045 		SPDK_ERRLOG("ICReq HPDA out of range 0 to 31, got %u\n", ic_req->hpda);
2046 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2047 		error_offset = offsetof(struct spdk_nvme_tcp_ic_req, hpda);
2048 		goto end;
2049 	}
2050 
2051 	/* MAXR2T is 0's based */
2052 	SPDK_DEBUGLOG(nvmf_tcp, "maxr2t =%u\n", (ic_req->maxr2t + 1u));
2053 
2054 	tqpair->host_hdgst_enable = ic_req->dgst.bits.hdgst_enable ? true : false;
2055 	if (!tqpair->host_hdgst_enable) {
2056 		tqpair->recv_buf_size -= SPDK_NVME_TCP_DIGEST_LEN * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
2057 	}
2058 
2059 	tqpair->host_ddgst_enable = ic_req->dgst.bits.ddgst_enable ? true : false;
2060 	if (!tqpair->host_ddgst_enable) {
2061 		tqpair->recv_buf_size -= SPDK_NVME_TCP_DIGEST_LEN * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
2062 	}
2063 
2064 	tqpair->recv_buf_size = spdk_max(tqpair->recv_buf_size, MIN_SOCK_PIPE_SIZE);
2065 	/* Now that we know whether digests are enabled, properly size the receive buffer */
2066 	if (spdk_sock_set_recvbuf(tqpair->sock, tqpair->recv_buf_size) < 0) {
2067 		SPDK_WARNLOG("Unable to allocate enough memory for receive buffer on tqpair=%p with size=%d\n",
2068 			     tqpair,
2069 			     tqpair->recv_buf_size);
2070 		/* Not fatal. */
2071 	}
2072 
2073 	tqpair->cpda = spdk_min(ic_req->hpda, SPDK_NVME_TCP_CPDA_MAX);
2074 	SPDK_DEBUGLOG(nvmf_tcp, "cpda of tqpair=(%p) is : %u\n", tqpair, tqpair->cpda);
2075 
2076 	rsp_pdu = tqpair->mgmt_pdu;
2077 
2078 	ic_resp = &rsp_pdu->hdr.ic_resp;
2079 	ic_resp->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_IC_RESP;
2080 	ic_resp->common.hlen = ic_resp->common.plen =  sizeof(*ic_resp);
2081 	ic_resp->pfv = 0;
2082 	ic_resp->cpda = tqpair->cpda;
2083 	ic_resp->maxh2cdata = ttransport->transport.opts.max_io_size;
2084 	ic_resp->dgst.bits.hdgst_enable = tqpair->host_hdgst_enable ? 1 : 0;
2085 	ic_resp->dgst.bits.ddgst_enable = tqpair->host_ddgst_enable ? 1 : 0;
2086 
2087 	SPDK_DEBUGLOG(nvmf_tcp, "host_hdgst_enable: %u\n", tqpair->host_hdgst_enable);
2088 	SPDK_DEBUGLOG(nvmf_tcp, "host_ddgst_enable: %u\n", tqpair->host_ddgst_enable);
2089 
2090 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_INITIALIZING);
2091 	nvmf_tcp_qpair_write_mgmt_pdu(tqpair, nvmf_tcp_send_icresp_complete, tqpair);
2092 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2093 	return;
2094 end:
2095 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
2096 }
2097 
2098 static void
2099 nvmf_tcp_pdu_psh_handle(struct spdk_nvmf_tcp_qpair *tqpair,
2100 			struct spdk_nvmf_tcp_transport *ttransport)
2101 {
2102 	struct nvme_tcp_pdu *pdu;
2103 	int rc;
2104 	uint32_t crc32c, error_offset = 0;
2105 	enum spdk_nvme_tcp_term_req_fes fes;
2106 
2107 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
2108 	pdu = tqpair->pdu_in_progress;
2109 
2110 	SPDK_DEBUGLOG(nvmf_tcp, "pdu type of tqpair(%p) is %d\n", tqpair,
2111 		      pdu->hdr.common.pdu_type);
2112 	/* check header digest if needed */
2113 	if (pdu->has_hdgst) {
2114 		SPDK_DEBUGLOG(nvmf_tcp, "Compare the header of pdu=%p on tqpair=%p\n", pdu, tqpair);
2115 		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
2116 		rc = MATCH_DIGEST_WORD((uint8_t *)pdu->hdr.raw + pdu->hdr.common.hlen, crc32c);
2117 		if (rc == 0) {
2118 			SPDK_ERRLOG("Header digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
2119 			fes = SPDK_NVME_TCP_TERM_REQ_FES_HDGST_ERROR;
2120 			nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
2121 			return;
2122 
2123 		}
2124 	}
2125 
2126 	switch (pdu->hdr.common.pdu_type) {
2127 	case SPDK_NVME_TCP_PDU_TYPE_IC_REQ:
2128 		nvmf_tcp_icreq_handle(ttransport, tqpair, pdu);
2129 		break;
2130 	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
2131 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_REQ);
2132 		break;
2133 	case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
2134 		nvmf_tcp_h2c_data_hdr_handle(ttransport, tqpair, pdu);
2135 		break;
2136 
2137 	case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
2138 		nvmf_tcp_h2c_term_req_hdr_handle(tqpair, pdu);
2139 		break;
2140 
2141 	default:
2142 		SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", tqpair->pdu_in_progress->hdr.common.pdu_type);
2143 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2144 		error_offset = 1;
2145 		nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
2146 		break;
2147 	}
2148 }
2149 
2150 static void
2151 nvmf_tcp_pdu_ch_handle(struct spdk_nvmf_tcp_qpair *tqpair)
2152 {
2153 	struct nvme_tcp_pdu *pdu;
2154 	uint32_t error_offset = 0;
2155 	enum spdk_nvme_tcp_term_req_fes fes;
2156 	uint8_t expected_hlen, pdo;
2157 	bool plen_error = false, pdo_error = false;
2158 
2159 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
2160 	pdu = tqpair->pdu_in_progress;
2161 	assert(pdu);
2162 	if (pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_REQ) {
2163 		if (tqpair->state != NVME_TCP_QPAIR_STATE_INVALID) {
2164 			SPDK_ERRLOG("Already received ICreq PDU, and reject this pdu=%p\n", pdu);
2165 			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
2166 			goto err;
2167 		}
2168 		expected_hlen = sizeof(struct spdk_nvme_tcp_ic_req);
2169 		if (pdu->hdr.common.plen != expected_hlen) {
2170 			plen_error = true;
2171 		}
2172 	} else {
2173 		if (tqpair->state != NVME_TCP_QPAIR_STATE_RUNNING) {
2174 			SPDK_ERRLOG("The TCP/IP connection is not negotiated\n");
2175 			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
2176 			goto err;
2177 		}
2178 
2179 		switch (pdu->hdr.common.pdu_type) {
2180 		case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
2181 			expected_hlen = sizeof(struct spdk_nvme_tcp_cmd);
2182 			pdo = pdu->hdr.common.pdo;
2183 			if ((tqpair->cpda != 0) && (pdo % ((tqpair->cpda + 1) << 2) != 0)) {
2184 				pdo_error = true;
2185 				break;
2186 			}
2187 
2188 			if (pdu->hdr.common.plen < expected_hlen) {
2189 				plen_error = true;
2190 			}
2191 			break;
2192 		case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
2193 			expected_hlen = sizeof(struct spdk_nvme_tcp_h2c_data_hdr);
2194 			pdo = pdu->hdr.common.pdo;
2195 			if ((tqpair->cpda != 0) && (pdo % ((tqpair->cpda + 1) << 2) != 0)) {
2196 				pdo_error = true;
2197 				break;
2198 			}
2199 			if (pdu->hdr.common.plen < expected_hlen) {
2200 				plen_error = true;
2201 			}
2202 			break;
2203 
2204 		case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
2205 			expected_hlen = sizeof(struct spdk_nvme_tcp_term_req_hdr);
2206 			if ((pdu->hdr.common.plen <= expected_hlen) ||
2207 			    (pdu->hdr.common.plen > SPDK_NVME_TCP_TERM_REQ_PDU_MAX_SIZE)) {
2208 				plen_error = true;
2209 			}
2210 			break;
2211 
2212 		default:
2213 			SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", pdu->hdr.common.pdu_type);
2214 			fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2215 			error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdu_type);
2216 			goto err;
2217 		}
2218 	}
2219 
2220 	if (pdu->hdr.common.hlen != expected_hlen) {
2221 		SPDK_ERRLOG("PDU type=0x%02x, Expected ICReq header length %u, got %u on tqpair=%p\n",
2222 			    pdu->hdr.common.pdu_type,
2223 			    expected_hlen, pdu->hdr.common.hlen, tqpair);
2224 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2225 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, hlen);
2226 		goto err;
2227 	} else if (pdo_error) {
2228 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2229 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdo);
2230 	} else if (plen_error) {
2231 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2232 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, plen);
2233 		goto err;
2234 	} else {
2235 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
2236 		nvme_tcp_pdu_calc_psh_len(tqpair->pdu_in_progress, tqpair->host_hdgst_enable);
2237 		return;
2238 	}
2239 err:
2240 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
2241 }
2242 
2243 static int
2244 nvmf_tcp_sock_process(struct spdk_nvmf_tcp_qpair *tqpair)
2245 {
2246 	int rc = 0;
2247 	struct nvme_tcp_pdu *pdu;
2248 	enum nvme_tcp_pdu_recv_state prev_state;
2249 	uint32_t data_len;
2250 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport,
2251 			struct spdk_nvmf_tcp_transport, transport);
2252 
2253 	/* The loop here is to allow for several back-to-back state changes. */
2254 	do {
2255 		prev_state = tqpair->recv_state;
2256 		SPDK_DEBUGLOG(nvmf_tcp, "tqpair(%p) recv pdu entering state %d\n", tqpair, prev_state);
2257 
2258 		pdu = tqpair->pdu_in_progress;
2259 		assert(pdu || tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2260 		switch (tqpair->recv_state) {
2261 		/* Wait for the common header  */
2262 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY:
2263 			if (!pdu) {
2264 				pdu = SLIST_FIRST(&tqpair->tcp_pdu_free_queue);
2265 				if (spdk_unlikely(!pdu)) {
2266 					return NVME_TCP_PDU_IN_PROGRESS;
2267 				}
2268 				SLIST_REMOVE_HEAD(&tqpair->tcp_pdu_free_queue, slist);
2269 				tqpair->pdu_in_progress = pdu;
2270 				tqpair->tcp_pdu_working_count++;
2271 			}
2272 			memset(pdu, 0, offsetof(struct nvme_tcp_pdu, qpair));
2273 			nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
2274 		/* FALLTHROUGH */
2275 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH:
2276 			if (spdk_unlikely(tqpair->state == NVME_TCP_QPAIR_STATE_INITIALIZING)) {
2277 				return rc;
2278 			}
2279 
2280 			rc = nvme_tcp_read_data(tqpair->sock,
2281 						sizeof(struct spdk_nvme_tcp_common_pdu_hdr) - pdu->ch_valid_bytes,
2282 						(void *)&pdu->hdr.common + pdu->ch_valid_bytes);
2283 			if (rc < 0) {
2284 				SPDK_DEBUGLOG(nvmf_tcp, "will disconnect tqpair=%p\n", tqpair);
2285 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_QUIESCING);
2286 				break;
2287 			} else if (rc > 0) {
2288 				pdu->ch_valid_bytes += rc;
2289 				spdk_trace_record(TRACE_TCP_READ_FROM_SOCKET_DONE, tqpair->qpair.qid, rc, 0, tqpair);
2290 			}
2291 
2292 			if (pdu->ch_valid_bytes < sizeof(struct spdk_nvme_tcp_common_pdu_hdr)) {
2293 				return NVME_TCP_PDU_IN_PROGRESS;
2294 			}
2295 
2296 			/* The command header of this PDU has now been read from the socket. */
2297 			nvmf_tcp_pdu_ch_handle(tqpair);
2298 			break;
2299 		/* Wait for the pdu specific header  */
2300 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH:
2301 			rc = nvme_tcp_read_data(tqpair->sock,
2302 						pdu->psh_len - pdu->psh_valid_bytes,
2303 						(void *)&pdu->hdr.raw + sizeof(struct spdk_nvme_tcp_common_pdu_hdr) + pdu->psh_valid_bytes);
2304 			if (rc < 0) {
2305 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_QUIESCING);
2306 				break;
2307 			} else if (rc > 0) {
2308 				spdk_trace_record(TRACE_TCP_READ_FROM_SOCKET_DONE, tqpair->qpair.qid, rc, 0, tqpair);
2309 				pdu->psh_valid_bytes += rc;
2310 			}
2311 
2312 			if (pdu->psh_valid_bytes < pdu->psh_len) {
2313 				return NVME_TCP_PDU_IN_PROGRESS;
2314 			}
2315 
2316 			/* All header(ch, psh, head digist) of this PDU has now been read from the socket. */
2317 			nvmf_tcp_pdu_psh_handle(tqpair, ttransport);
2318 			break;
2319 		/* Wait for the req slot */
2320 		case NVME_TCP_PDU_RECV_STATE_AWAIT_REQ:
2321 			nvmf_tcp_capsule_cmd_hdr_handle(ttransport, tqpair, pdu);
2322 			break;
2323 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:
2324 			/* check whether the data is valid, if not we just return */
2325 			if (!pdu->data_len) {
2326 				return NVME_TCP_PDU_IN_PROGRESS;
2327 			}
2328 
2329 			data_len = pdu->data_len;
2330 			/* data digest */
2331 			if (spdk_unlikely((pdu->hdr.common.pdu_type != SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ) &&
2332 					  tqpair->host_ddgst_enable)) {
2333 				data_len += SPDK_NVME_TCP_DIGEST_LEN;
2334 				pdu->ddgst_enable = true;
2335 			}
2336 
2337 			rc = nvme_tcp_read_payload_data(tqpair->sock, pdu);
2338 			if (rc < 0) {
2339 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_QUIESCING);
2340 				break;
2341 			}
2342 			pdu->rw_offset += rc;
2343 
2344 			if (pdu->rw_offset < data_len) {
2345 				return NVME_TCP_PDU_IN_PROGRESS;
2346 			}
2347 
2348 			/* Generate and insert DIF to whole data block received if DIF is enabled */
2349 			if (spdk_unlikely(pdu->dif_ctx != NULL) &&
2350 			    spdk_dif_generate_stream(pdu->data_iov, pdu->data_iovcnt, 0, data_len,
2351 						     pdu->dif_ctx) != 0) {
2352 				SPDK_ERRLOG("DIF generate failed\n");
2353 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_QUIESCING);
2354 				break;
2355 			}
2356 
2357 			/* All of this PDU has now been read from the socket. */
2358 			nvmf_tcp_pdu_payload_handle(tqpair, pdu);
2359 			break;
2360 		case NVME_TCP_PDU_RECV_STATE_QUIESCING:
2361 			if (tqpair->tcp_pdu_working_count != 0) {
2362 				return NVME_TCP_PDU_IN_PROGRESS;
2363 			}
2364 			nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
2365 			break;
2366 		case NVME_TCP_PDU_RECV_STATE_ERROR:
2367 			if (!spdk_sock_is_connected(tqpair->sock)) {
2368 				return NVME_TCP_PDU_FATAL;
2369 			}
2370 			return NVME_TCP_PDU_IN_PROGRESS;
2371 		default:
2372 			SPDK_ERRLOG("The state(%d) is invalid\n", tqpair->recv_state);
2373 			abort();
2374 			break;
2375 		}
2376 	} while (tqpair->recv_state != prev_state);
2377 
2378 	return rc;
2379 }
2380 
2381 static inline void *
2382 nvmf_tcp_control_msg_get(struct spdk_nvmf_tcp_control_msg_list *list)
2383 {
2384 	struct spdk_nvmf_tcp_control_msg *msg;
2385 
2386 	assert(list);
2387 
2388 	msg = STAILQ_FIRST(&list->free_msgs);
2389 	if (!msg) {
2390 		SPDK_DEBUGLOG(nvmf_tcp, "Out of control messages\n");
2391 		return NULL;
2392 	}
2393 	STAILQ_REMOVE_HEAD(&list->free_msgs, link);
2394 	return msg;
2395 }
2396 
2397 static inline void
2398 nvmf_tcp_control_msg_put(struct spdk_nvmf_tcp_control_msg_list *list, void *_msg)
2399 {
2400 	struct spdk_nvmf_tcp_control_msg *msg = _msg;
2401 
2402 	assert(list);
2403 	STAILQ_INSERT_HEAD(&list->free_msgs, msg, link);
2404 }
2405 
2406 static int
2407 nvmf_tcp_req_parse_sgl(struct spdk_nvmf_tcp_req *tcp_req,
2408 		       struct spdk_nvmf_transport *transport,
2409 		       struct spdk_nvmf_transport_poll_group *group)
2410 {
2411 	struct spdk_nvmf_request		*req = &tcp_req->req;
2412 	struct spdk_nvme_cmd			*cmd;
2413 	struct spdk_nvme_sgl_descriptor		*sgl;
2414 	struct spdk_nvmf_tcp_poll_group		*tgroup;
2415 	enum spdk_nvme_tcp_term_req_fes		fes;
2416 	struct nvme_tcp_pdu			*pdu;
2417 	struct spdk_nvmf_tcp_qpair		*tqpair;
2418 	uint32_t				length, error_offset = 0;
2419 
2420 	cmd = &req->cmd->nvme_cmd;
2421 	sgl = &cmd->dptr.sgl1;
2422 
2423 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK &&
2424 	    sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_TRANSPORT) {
2425 		/* get request length from sgl */
2426 		length = sgl->unkeyed.length;
2427 		if (spdk_unlikely(length > transport->opts.max_io_size)) {
2428 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
2429 				    length, transport->opts.max_io_size);
2430 			fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_LIMIT_EXCEEDED;
2431 			goto fatal_err;
2432 		}
2433 
2434 		/* fill request length and populate iovs */
2435 		req->length = length;
2436 
2437 		SPDK_DEBUGLOG(nvmf_tcp, "Data requested length= 0x%x\n", length);
2438 
2439 		if (spdk_unlikely(req->dif_enabled)) {
2440 			req->dif.orig_length = length;
2441 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
2442 			req->dif.elba_length = length;
2443 		}
2444 
2445 		if (nvmf_ctrlr_use_zcopy(req)) {
2446 			SPDK_DEBUGLOG(nvmf_tcp, "Using zero-copy to execute request %p\n", tcp_req);
2447 			req->data_from_pool = false;
2448 			return 0;
2449 		}
2450 
2451 		if (spdk_nvmf_request_get_buffers(req, group, transport, length)) {
2452 			/* No available buffers. Queue this request up. */
2453 			SPDK_DEBUGLOG(nvmf_tcp, "No available large data buffers. Queueing request %p\n",
2454 				      tcp_req);
2455 			return 0;
2456 		}
2457 
2458 		/* backward compatible */
2459 		req->data = req->iov[0].iov_base;
2460 
2461 		SPDK_DEBUGLOG(nvmf_tcp, "Request %p took %d buffer/s from central pool, and data=%p\n",
2462 			      tcp_req, req->iovcnt, req->iov[0].iov_base);
2463 
2464 		return 0;
2465 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
2466 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
2467 		uint64_t offset = sgl->address;
2468 		uint32_t max_len = transport->opts.in_capsule_data_size;
2469 
2470 		assert(tcp_req->has_in_capsule_data);
2471 		/* Capsule Cmd with In-capsule Data should get data length from pdu header */
2472 		tqpair = tcp_req->pdu->qpair;
2473 		/* receiving pdu is not same with the pdu in tcp_req */
2474 		pdu = tqpair->pdu_in_progress;
2475 		length = pdu->hdr.common.plen - pdu->psh_len - sizeof(struct spdk_nvme_tcp_common_pdu_hdr);
2476 		if (tqpair->host_ddgst_enable) {
2477 			length -= SPDK_NVME_TCP_DIGEST_LEN;
2478 		}
2479 		/* This error is not defined in NVMe/TCP spec, take this error as fatal error */
2480 		if (spdk_unlikely(length != sgl->unkeyed.length)) {
2481 			SPDK_ERRLOG("In-Capsule Data length 0x%x is not equal to SGL data length 0x%x\n",
2482 				    length, sgl->unkeyed.length);
2483 			fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2484 			error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, plen);
2485 			goto fatal_err;
2486 		}
2487 
2488 		SPDK_DEBUGLOG(nvmf_tcp, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
2489 			      offset, length);
2490 
2491 		/* The NVMe/TCP transport does not use ICDOFF to control the in-capsule data offset. ICDOFF should be '0' */
2492 		if (spdk_unlikely(offset != 0)) {
2493 			/* Not defined fatal error in NVMe/TCP spec, handle this error as a fatal error */
2494 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " should be ZERO in NVMe/TCP\n", offset);
2495 			fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER;
2496 			error_offset = offsetof(struct spdk_nvme_tcp_cmd, ccsqe.dptr.sgl1.address);
2497 			goto fatal_err;
2498 		}
2499 
2500 		if (spdk_unlikely(length > max_len)) {
2501 			/* According to the SPEC we should support ICD up to 8192 bytes for admin and fabric commands */
2502 			if (length <= SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE &&
2503 			    (cmd->opc == SPDK_NVME_OPC_FABRIC || req->qpair->qid == 0)) {
2504 
2505 				/* Get a buffer from dedicated list */
2506 				SPDK_DEBUGLOG(nvmf_tcp, "Getting a buffer from control msg list\n");
2507 				tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2508 				assert(tgroup->control_msg_list);
2509 				req->iov[0].iov_base = nvmf_tcp_control_msg_get(tgroup->control_msg_list);
2510 				if (!req->iov[0].iov_base) {
2511 					/* No available buffers. Queue this request up. */
2512 					SPDK_DEBUGLOG(nvmf_tcp, "No available ICD buffers. Queueing request %p\n", tcp_req);
2513 					return 0;
2514 				}
2515 			} else {
2516 				SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
2517 					    length, max_len);
2518 				fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_LIMIT_EXCEEDED;
2519 				goto fatal_err;
2520 			}
2521 		} else {
2522 			req->iov[0].iov_base = tcp_req->buf;
2523 		}
2524 
2525 		req->length = length;
2526 		req->data_from_pool = false;
2527 		req->data = req->iov[0].iov_base;
2528 
2529 		if (spdk_unlikely(req->dif_enabled)) {
2530 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
2531 			req->dif.elba_length = length;
2532 		}
2533 
2534 		req->iov[0].iov_len = length;
2535 		req->iovcnt = 1;
2536 
2537 		return 0;
2538 	}
2539 	/* If we want to handle the problem here, then we can't skip the following data segment.
2540 	 * Because this function runs before reading data part, now handle all errors as fatal errors. */
2541 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
2542 		    sgl->generic.type, sgl->generic.subtype);
2543 	fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER;
2544 	error_offset = offsetof(struct spdk_nvme_tcp_cmd, ccsqe.dptr.sgl1.generic);
2545 fatal_err:
2546 	nvmf_tcp_send_c2h_term_req(tcp_req->pdu->qpair, tcp_req->pdu, fes, error_offset);
2547 	return -1;
2548 }
2549 
2550 static inline enum spdk_nvme_media_error_status_code
2551 nvmf_tcp_dif_error_to_compl_status(uint8_t err_type) {
2552 	enum spdk_nvme_media_error_status_code result;
2553 
2554 	switch (err_type)
2555 	{
2556 	case SPDK_DIF_REFTAG_ERROR:
2557 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
2558 		break;
2559 	case SPDK_DIF_APPTAG_ERROR:
2560 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
2561 		break;
2562 	case SPDK_DIF_GUARD_ERROR:
2563 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
2564 		break;
2565 	default:
2566 		SPDK_UNREACHABLE();
2567 		break;
2568 	}
2569 
2570 	return result;
2571 }
2572 
2573 static void
2574 _nvmf_tcp_send_c2h_data(struct spdk_nvmf_tcp_qpair *tqpair,
2575 			struct spdk_nvmf_tcp_req *tcp_req)
2576 {
2577 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(
2578 				tqpair->qpair.transport, struct spdk_nvmf_tcp_transport, transport);
2579 	struct nvme_tcp_pdu *rsp_pdu;
2580 	struct spdk_nvme_tcp_c2h_data_hdr *c2h_data;
2581 	uint32_t plen, pdo, alignment;
2582 	int rc;
2583 
2584 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
2585 
2586 	rsp_pdu = tcp_req->pdu;
2587 	assert(rsp_pdu != NULL);
2588 
2589 	c2h_data = &rsp_pdu->hdr.c2h_data;
2590 	c2h_data->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_C2H_DATA;
2591 	plen = c2h_data->common.hlen = sizeof(*c2h_data);
2592 
2593 	if (tqpair->host_hdgst_enable) {
2594 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2595 		c2h_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
2596 	}
2597 
2598 	/* set the psh */
2599 	c2h_data->cccid = tcp_req->req.cmd->nvme_cmd.cid;
2600 	c2h_data->datal = tcp_req->req.length - tcp_req->pdu->rw_offset;
2601 	c2h_data->datao = tcp_req->pdu->rw_offset;
2602 
2603 	/* set the padding */
2604 	rsp_pdu->padding_len = 0;
2605 	pdo = plen;
2606 	if (tqpair->cpda) {
2607 		alignment = (tqpair->cpda + 1) << 2;
2608 		if (plen % alignment != 0) {
2609 			pdo = (plen + alignment) / alignment * alignment;
2610 			rsp_pdu->padding_len = pdo - plen;
2611 			plen = pdo;
2612 		}
2613 	}
2614 
2615 	c2h_data->common.pdo = pdo;
2616 	plen += c2h_data->datal;
2617 	if (tqpair->host_ddgst_enable) {
2618 		c2h_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_DDGSTF;
2619 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2620 	}
2621 
2622 	c2h_data->common.plen = plen;
2623 
2624 	if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2625 		rsp_pdu->dif_ctx = &tcp_req->req.dif.dif_ctx;
2626 	}
2627 
2628 	nvme_tcp_pdu_set_data_buf(rsp_pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
2629 				  c2h_data->datao, c2h_data->datal);
2630 
2631 
2632 	c2h_data->common.flags |= SPDK_NVME_TCP_C2H_DATA_FLAGS_LAST_PDU;
2633 	/* Need to send the capsule response if response is not all 0 */
2634 	if (ttransport->tcp_opts.c2h_success &&
2635 	    tcp_req->rsp.cdw0 == 0 && tcp_req->rsp.cdw1 == 0) {
2636 		c2h_data->common.flags |= SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS;
2637 	}
2638 
2639 	if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2640 		struct spdk_nvme_cpl *rsp = &tcp_req->req.rsp->nvme_cpl;
2641 		struct spdk_dif_error err_blk = {};
2642 		uint32_t mapped_length = 0;
2643 		uint32_t available_iovs = SPDK_COUNTOF(rsp_pdu->iov);
2644 		uint32_t ddgst_len = 0;
2645 
2646 		if (tqpair->host_ddgst_enable) {
2647 			/* Data digest consumes additional iov entry */
2648 			available_iovs--;
2649 			/* plen needs to be updated since nvme_tcp_build_iovs compares expected and actual plen */
2650 			ddgst_len = SPDK_NVME_TCP_DIGEST_LEN;
2651 			c2h_data->common.plen -= ddgst_len;
2652 		}
2653 		/* Temp call to estimate if data can be described by limited number of iovs.
2654 		 * iov vector will be rebuilt in nvmf_tcp_qpair_write_pdu */
2655 		nvme_tcp_build_iovs(rsp_pdu->iov, available_iovs, rsp_pdu, tqpair->host_hdgst_enable,
2656 				    false, &mapped_length);
2657 
2658 		if (mapped_length != c2h_data->common.plen) {
2659 			c2h_data->datal = mapped_length - (c2h_data->common.plen - c2h_data->datal);
2660 			SPDK_DEBUGLOG(nvmf_tcp,
2661 				      "Part C2H, data_len %u (of %u), PDU len %u, updated PDU len %u, offset %u\n",
2662 				      c2h_data->datal, tcp_req->req.length, c2h_data->common.plen, mapped_length, rsp_pdu->rw_offset);
2663 			c2h_data->common.plen = mapped_length;
2664 
2665 			/* Rebuild pdu->data_iov since data length is changed */
2666 			nvme_tcp_pdu_set_data_buf(rsp_pdu, tcp_req->req.iov, tcp_req->req.iovcnt, c2h_data->datao,
2667 						  c2h_data->datal);
2668 
2669 			c2h_data->common.flags &= ~(SPDK_NVME_TCP_C2H_DATA_FLAGS_LAST_PDU |
2670 						    SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS);
2671 		}
2672 
2673 		c2h_data->common.plen += ddgst_len;
2674 
2675 		assert(rsp_pdu->rw_offset <= tcp_req->req.length);
2676 
2677 		rc = spdk_dif_verify_stream(rsp_pdu->data_iov, rsp_pdu->data_iovcnt,
2678 					    0, rsp_pdu->data_len, rsp_pdu->dif_ctx, &err_blk);
2679 		if (rc != 0) {
2680 			SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n",
2681 				    err_blk.err_type, err_blk.err_offset);
2682 			rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2683 			rsp->status.sc = nvmf_tcp_dif_error_to_compl_status(err_blk.err_type);
2684 			nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
2685 			return;
2686 		}
2687 	}
2688 
2689 	rsp_pdu->rw_offset += c2h_data->datal;
2690 	nvmf_tcp_qpair_write_req_pdu(tqpair, tcp_req, nvmf_tcp_pdu_c2h_data_complete, tcp_req);
2691 }
2692 
2693 static void
2694 nvmf_tcp_send_c2h_data(struct spdk_nvmf_tcp_qpair *tqpair,
2695 		       struct spdk_nvmf_tcp_req *tcp_req)
2696 {
2697 	nvmf_tcp_req_pdu_init(tcp_req);
2698 	_nvmf_tcp_send_c2h_data(tqpair, tcp_req);
2699 }
2700 
2701 static int
2702 request_transfer_out(struct spdk_nvmf_request *req)
2703 {
2704 	struct spdk_nvmf_tcp_req	*tcp_req;
2705 	struct spdk_nvmf_qpair		*qpair;
2706 	struct spdk_nvmf_tcp_qpair	*tqpair;
2707 	struct spdk_nvme_cpl		*rsp;
2708 
2709 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
2710 
2711 	qpair = req->qpair;
2712 	rsp = &req->rsp->nvme_cpl;
2713 	tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
2714 
2715 	/* Advance our sq_head pointer */
2716 	if (qpair->sq_head == qpair->sq_head_max) {
2717 		qpair->sq_head = 0;
2718 	} else {
2719 		qpair->sq_head++;
2720 	}
2721 	rsp->sqhd = qpair->sq_head;
2722 
2723 	tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
2724 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST);
2725 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS && req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2726 		nvmf_tcp_send_c2h_data(tqpair, tcp_req);
2727 	} else {
2728 		nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
2729 	}
2730 
2731 	return 0;
2732 }
2733 
2734 static void
2735 nvmf_tcp_check_fused_ordering(struct spdk_nvmf_tcp_transport *ttransport,
2736 			      struct spdk_nvmf_tcp_qpair *tqpair,
2737 			      struct spdk_nvmf_tcp_req *tcp_req)
2738 {
2739 	enum spdk_nvme_cmd_fuse last, next;
2740 
2741 	last = tqpair->fused_first ? tqpair->fused_first->cmd.fuse : SPDK_NVME_CMD_FUSE_NONE;
2742 	next = tcp_req->cmd.fuse;
2743 
2744 	assert(last != SPDK_NVME_CMD_FUSE_SECOND);
2745 
2746 	if (spdk_likely(last == SPDK_NVME_CMD_FUSE_NONE && next == SPDK_NVME_CMD_FUSE_NONE)) {
2747 		return;
2748 	}
2749 
2750 	if (last == SPDK_NVME_CMD_FUSE_FIRST) {
2751 		if (next == SPDK_NVME_CMD_FUSE_SECOND) {
2752 			/* This is a valid pair of fused commands.  Point them at each other
2753 			 * so they can be submitted consecutively once ready to be executed.
2754 			 */
2755 			tqpair->fused_first->fused_pair = tcp_req;
2756 			tcp_req->fused_pair = tqpair->fused_first;
2757 			tqpair->fused_first = NULL;
2758 			return;
2759 		} else {
2760 			/* Mark the last req as failed since it wasn't followed by a SECOND. */
2761 			tqpair->fused_first->fused_failed = true;
2762 
2763 			/*
2764 			 * If the last req is in READY_TO_EXECUTE state, then call
2765 			 * nvmf_tcp_req_process(), otherwise nothing else will kick it.
2766 			 */
2767 			if (tqpair->fused_first->state == TCP_REQUEST_STATE_READY_TO_EXECUTE) {
2768 				nvmf_tcp_req_process(ttransport, tqpair->fused_first);
2769 			}
2770 
2771 			tqpair->fused_first = NULL;
2772 		}
2773 	}
2774 
2775 	if (next == SPDK_NVME_CMD_FUSE_FIRST) {
2776 		/* Set tqpair->fused_first here so that we know to check that the next request
2777 		 * is a SECOND (and to fail this one if it isn't).
2778 		 */
2779 		tqpair->fused_first = tcp_req;
2780 	} else if (next == SPDK_NVME_CMD_FUSE_SECOND) {
2781 		/* Mark this req failed since it is a SECOND and the last one was not a FIRST. */
2782 		tcp_req->fused_failed = true;
2783 	}
2784 }
2785 
2786 static bool
2787 nvmf_tcp_req_process(struct spdk_nvmf_tcp_transport *ttransport,
2788 		     struct spdk_nvmf_tcp_req *tcp_req)
2789 {
2790 	struct spdk_nvmf_tcp_qpair		*tqpair;
2791 	uint32_t				plen;
2792 	struct nvme_tcp_pdu			*pdu;
2793 	enum spdk_nvmf_tcp_req_state		prev_state;
2794 	bool					progress = false;
2795 	struct spdk_nvmf_transport		*transport = &ttransport->transport;
2796 	struct spdk_nvmf_transport_poll_group	*group;
2797 	struct spdk_nvmf_tcp_poll_group		*tgroup;
2798 
2799 	tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
2800 	group = &tqpair->group->group;
2801 	assert(tcp_req->state != TCP_REQUEST_STATE_FREE);
2802 
2803 	/* If the qpair is not active, we need to abort the outstanding requests. */
2804 	if (tqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
2805 		if (tcp_req->state == TCP_REQUEST_STATE_NEED_BUFFER) {
2806 			STAILQ_REMOVE(&group->pending_buf_queue, &tcp_req->req, spdk_nvmf_request, buf_link);
2807 		}
2808 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
2809 	}
2810 
2811 	/* The loop here is to allow for several back-to-back state changes. */
2812 	do {
2813 		prev_state = tcp_req->state;
2814 
2815 		SPDK_DEBUGLOG(nvmf_tcp, "Request %p entering state %d on tqpair=%p\n", tcp_req, prev_state,
2816 			      tqpair);
2817 
2818 		switch (tcp_req->state) {
2819 		case TCP_REQUEST_STATE_FREE:
2820 			/* Some external code must kick a request into TCP_REQUEST_STATE_NEW
2821 			 * to escape this state. */
2822 			break;
2823 		case TCP_REQUEST_STATE_NEW:
2824 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_NEW, tqpair->qpair.qid, 0, (uintptr_t)tcp_req, tqpair);
2825 
2826 			/* copy the cmd from the receive pdu */
2827 			tcp_req->cmd = tqpair->pdu_in_progress->hdr.capsule_cmd.ccsqe;
2828 
2829 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&tcp_req->req, &tcp_req->req.dif.dif_ctx))) {
2830 				tcp_req->req.dif_enabled = true;
2831 				tqpair->pdu_in_progress->dif_ctx = &tcp_req->req.dif.dif_ctx;
2832 			}
2833 
2834 			nvmf_tcp_check_fused_ordering(ttransport, tqpair, tcp_req);
2835 
2836 			/* The next state transition depends on the data transfer needs of this request. */
2837 			tcp_req->req.xfer = spdk_nvmf_req_get_xfer(&tcp_req->req);
2838 
2839 			if (spdk_unlikely(tcp_req->req.xfer == SPDK_NVME_DATA_BIDIRECTIONAL)) {
2840 				tcp_req->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
2841 				tcp_req->req.rsp->nvme_cpl.status.sc  = SPDK_NVME_SC_INVALID_OPCODE;
2842 				tcp_req->req.rsp->nvme_cpl.cid = tcp_req->req.cmd->nvme_cmd.cid;
2843 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2844 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2845 				SPDK_DEBUGLOG(nvmf_tcp, "Request %p: invalid xfer type (BIDIRECTIONAL)\n", tcp_req);
2846 				break;
2847 			}
2848 
2849 			/* If no data to transfer, ready to execute. */
2850 			if (tcp_req->req.xfer == SPDK_NVME_DATA_NONE) {
2851 				/* Reset the tqpair receiving pdu state */
2852 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2853 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
2854 				break;
2855 			}
2856 
2857 			pdu = tqpair->pdu_in_progress;
2858 			plen = pdu->hdr.common.hlen;
2859 			if (tqpair->host_hdgst_enable) {
2860 				plen += SPDK_NVME_TCP_DIGEST_LEN;
2861 			}
2862 			if (pdu->hdr.common.plen != plen) {
2863 				tcp_req->has_in_capsule_data = true;
2864 			} else {
2865 				/* Data is transmitted by C2H PDUs */
2866 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2867 			}
2868 
2869 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEED_BUFFER);
2870 			STAILQ_INSERT_TAIL(&group->pending_buf_queue, &tcp_req->req, buf_link);
2871 			break;
2872 		case TCP_REQUEST_STATE_NEED_BUFFER:
2873 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_NEED_BUFFER, tqpair->qpair.qid, 0, (uintptr_t)tcp_req,
2874 					  tqpair);
2875 
2876 			assert(tcp_req->req.xfer != SPDK_NVME_DATA_NONE);
2877 
2878 			if (!tcp_req->has_in_capsule_data && (&tcp_req->req != STAILQ_FIRST(&group->pending_buf_queue))) {
2879 				SPDK_DEBUGLOG(nvmf_tcp,
2880 					      "Not the first element to wait for the buf for tcp_req(%p) on tqpair=%p\n",
2881 					      tcp_req, tqpair);
2882 				/* This request needs to wait in line to obtain a buffer */
2883 				break;
2884 			}
2885 
2886 			/* Try to get a data buffer */
2887 			if (nvmf_tcp_req_parse_sgl(tcp_req, transport, group) < 0) {
2888 				break;
2889 			}
2890 
2891 			/* Get a zcopy buffer if the request can be serviced through zcopy */
2892 			if (spdk_nvmf_request_using_zcopy(&tcp_req->req)) {
2893 				if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2894 					assert(tcp_req->req.dif.elba_length >= tcp_req->req.length);
2895 					tcp_req->req.length = tcp_req->req.dif.elba_length;
2896 				}
2897 
2898 				STAILQ_REMOVE(&group->pending_buf_queue, &tcp_req->req, spdk_nvmf_request, buf_link);
2899 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_ZCOPY_START);
2900 				spdk_nvmf_request_zcopy_start(&tcp_req->req);
2901 				break;
2902 			}
2903 
2904 			if (tcp_req->req.iovcnt < 1) {
2905 				SPDK_DEBUGLOG(nvmf_tcp, "No buffer allocated for tcp_req(%p) on tqpair(%p\n)",
2906 					      tcp_req, tqpair);
2907 				/* No buffers available. */
2908 				break;
2909 			}
2910 
2911 			STAILQ_REMOVE(&group->pending_buf_queue, &tcp_req->req, spdk_nvmf_request, buf_link);
2912 
2913 			/* If data is transferring from host to controller, we need to do a transfer from the host. */
2914 			if (tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2915 				if (tcp_req->req.data_from_pool) {
2916 					SPDK_DEBUGLOG(nvmf_tcp, "Sending R2T for tcp_req(%p) on tqpair=%p\n", tcp_req, tqpair);
2917 					nvmf_tcp_send_r2t_pdu(tqpair, tcp_req);
2918 				} else {
2919 					struct nvme_tcp_pdu *pdu;
2920 
2921 					nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
2922 
2923 					pdu = tqpair->pdu_in_progress;
2924 					SPDK_DEBUGLOG(nvmf_tcp, "Not need to send r2t for tcp_req(%p) on tqpair=%p\n", tcp_req,
2925 						      tqpair);
2926 					/* No need to send r2t, contained in the capsuled data */
2927 					nvme_tcp_pdu_set_data_buf(pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
2928 								  0, tcp_req->req.length);
2929 					nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
2930 				}
2931 				break;
2932 			}
2933 
2934 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
2935 			break;
2936 		case TCP_REQUEST_STATE_AWAITING_ZCOPY_START:
2937 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_START, tqpair->qpair.qid, 0,
2938 					  (uintptr_t)tcp_req, tqpair);
2939 			/* Some external code must kick a request into  TCP_REQUEST_STATE_ZCOPY_START_COMPLETED
2940 			 * to escape this state. */
2941 			break;
2942 		case TCP_REQUEST_STATE_ZCOPY_START_COMPLETED:
2943 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_ZCOPY_START_COMPLETED, tqpair->qpair.qid, 0,
2944 					  (uintptr_t)tcp_req, tqpair);
2945 			if (spdk_unlikely(spdk_nvme_cpl_is_error(&tcp_req->req.rsp->nvme_cpl))) {
2946 				SPDK_DEBUGLOG(nvmf_tcp, "Zero-copy start failed for tcp_req(%p) on tqpair=%p\n",
2947 					      tcp_req, tqpair);
2948 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2949 				break;
2950 			}
2951 			if (tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2952 				SPDK_DEBUGLOG(nvmf_tcp, "Sending R2T for tcp_req(%p) on tqpair=%p\n", tcp_req, tqpair);
2953 				nvmf_tcp_send_r2t_pdu(tqpair, tcp_req);
2954 			} else {
2955 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTED);
2956 			}
2957 			break;
2958 		case TCP_REQUEST_STATE_AWAITING_R2T_ACK:
2959 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_R2T_ACK, tqpair->qpair.qid, 0, (uintptr_t)tcp_req,
2960 					  tqpair);
2961 			/* The R2T completion or the h2c data incoming will kick it out of this state. */
2962 			break;
2963 		case TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2964 
2965 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, tqpair->qpair.qid, 0,
2966 					  (uintptr_t)tcp_req, tqpair);
2967 			/* Some external code must kick a request into TCP_REQUEST_STATE_READY_TO_EXECUTE
2968 			 * to escape this state. */
2969 			break;
2970 		case TCP_REQUEST_STATE_READY_TO_EXECUTE:
2971 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE, tqpair->qpair.qid, 0,
2972 					  (uintptr_t)tcp_req, tqpair);
2973 
2974 			if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2975 				assert(tcp_req->req.dif.elba_length >= tcp_req->req.length);
2976 				tcp_req->req.length = tcp_req->req.dif.elba_length;
2977 			}
2978 
2979 			if (tcp_req->cmd.fuse != SPDK_NVME_CMD_FUSE_NONE) {
2980 				if (tcp_req->fused_failed) {
2981 					/* This request failed FUSED semantics.  Fail it immediately, without
2982 					 * even sending it to the target layer.
2983 					 */
2984 					tcp_req->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
2985 					tcp_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_MISSING_FUSED;
2986 					tcp_req->req.rsp->nvme_cpl.cid = tcp_req->req.cmd->nvme_cmd.cid;
2987 					nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2988 					break;
2989 				}
2990 
2991 				if (tcp_req->fused_pair == NULL ||
2992 				    tcp_req->fused_pair->state != TCP_REQUEST_STATE_READY_TO_EXECUTE) {
2993 					/* This request is ready to execute, but either we don't know yet if it's
2994 					 * valid - i.e. this is a FIRST but we haven't received the next request yet),
2995 					 * or the other request of this fused pair isn't ready to execute. So
2996 					 * break here and this request will get processed later either when the
2997 					 * other request is ready or we find that this request isn't valid.
2998 					 */
2999 					break;
3000 				}
3001 			}
3002 
3003 			if (!spdk_nvmf_request_using_zcopy(&tcp_req->req)) {
3004 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTING);
3005 				/* If we get to this point, and this request is a fused command, we know that
3006 				 * it is part of a valid sequence (FIRST followed by a SECOND) and that both
3007 				 * requests are READY_TO_EXECUTE.  So call spdk_nvmf_request_exec() both on this
3008 				 * request, and the other request of the fused pair, in the correct order.
3009 				 * Also clear the ->fused_pair pointers on both requests, since after this point
3010 				 * we no longer need to maintain the relationship between these two requests.
3011 				 */
3012 				if (tcp_req->cmd.fuse == SPDK_NVME_CMD_FUSE_SECOND) {
3013 					assert(tcp_req->fused_pair != NULL);
3014 					assert(tcp_req->fused_pair->fused_pair == tcp_req);
3015 					nvmf_tcp_req_set_state(tcp_req->fused_pair, TCP_REQUEST_STATE_EXECUTING);
3016 					spdk_nvmf_request_exec(&tcp_req->fused_pair->req);
3017 					tcp_req->fused_pair->fused_pair = NULL;
3018 					tcp_req->fused_pair = NULL;
3019 				}
3020 				spdk_nvmf_request_exec(&tcp_req->req);
3021 				if (tcp_req->cmd.fuse == SPDK_NVME_CMD_FUSE_FIRST) {
3022 					assert(tcp_req->fused_pair != NULL);
3023 					assert(tcp_req->fused_pair->fused_pair == tcp_req);
3024 					nvmf_tcp_req_set_state(tcp_req->fused_pair, TCP_REQUEST_STATE_EXECUTING);
3025 					spdk_nvmf_request_exec(&tcp_req->fused_pair->req);
3026 					tcp_req->fused_pair->fused_pair = NULL;
3027 					tcp_req->fused_pair = NULL;
3028 				}
3029 			} else {
3030 				/* For zero-copy, only requests with data coming from host to the
3031 				 * controller can end up here. */
3032 				assert(tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
3033 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT);
3034 				spdk_nvmf_request_zcopy_end(&tcp_req->req, true);
3035 			}
3036 
3037 			break;
3038 		case TCP_REQUEST_STATE_EXECUTING:
3039 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_EXECUTING, tqpair->qpair.qid, 0, (uintptr_t)tcp_req,
3040 					  tqpair);
3041 			/* Some external code must kick a request into TCP_REQUEST_STATE_EXECUTED
3042 			 * to escape this state. */
3043 			break;
3044 		case TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT:
3045 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_COMMIT, tqpair->qpair.qid, 0,
3046 					  (uintptr_t)tcp_req, tqpair);
3047 			/* Some external code must kick a request into TCP_REQUEST_STATE_EXECUTED
3048 			 * to escape this state. */
3049 			break;
3050 		case TCP_REQUEST_STATE_EXECUTED:
3051 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_EXECUTED, tqpair->qpair.qid, 0, (uintptr_t)tcp_req,
3052 					  tqpair);
3053 
3054 			if (spdk_unlikely(tcp_req->req.dif_enabled)) {
3055 				tcp_req->req.length = tcp_req->req.dif.orig_length;
3056 			}
3057 
3058 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
3059 			break;
3060 		case TCP_REQUEST_STATE_READY_TO_COMPLETE:
3061 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE, tqpair->qpair.qid, 0,
3062 					  (uintptr_t)tcp_req, tqpair);
3063 			if (request_transfer_out(&tcp_req->req) != 0) {
3064 				assert(0); /* No good way to handle this currently */
3065 			}
3066 			break;
3067 		case TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
3068 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, tqpair->qpair.qid, 0,
3069 					  (uintptr_t)tcp_req, tqpair);
3070 			/* Some external code must kick a request into TCP_REQUEST_STATE_COMPLETED
3071 			 * to escape this state. */
3072 			break;
3073 		case TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE:
3074 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_RELEASE, tqpair->qpair.qid, 0,
3075 					  (uintptr_t)tcp_req, tqpair);
3076 			/* Some external code must kick a request into TCP_REQUEST_STATE_COMPLETED
3077 			 * to escape this state. */
3078 			break;
3079 		case TCP_REQUEST_STATE_COMPLETED:
3080 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_COMPLETED, tqpair->qpair.qid, 0, (uintptr_t)tcp_req,
3081 					  tqpair);
3082 			/* If there's an outstanding PDU sent to the host, the request is completed
3083 			 * due to the qpair being disconnected.  We must delay the completion until
3084 			 * that write is done to avoid freeing the request twice. */
3085 			if (spdk_unlikely(tcp_req->pdu_in_use)) {
3086 				SPDK_DEBUGLOG(nvmf_tcp, "Delaying completion due to outstanding "
3087 					      "write on req=%p\n", tcp_req);
3088 				/* This can only happen for zcopy requests */
3089 				assert(spdk_nvmf_request_using_zcopy(&tcp_req->req));
3090 				assert(tqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE);
3091 				break;
3092 			}
3093 
3094 			if (tcp_req->req.data_from_pool) {
3095 				spdk_nvmf_request_free_buffers(&tcp_req->req, group, transport);
3096 			} else if (spdk_unlikely(tcp_req->has_in_capsule_data &&
3097 						 (tcp_req->cmd.opc == SPDK_NVME_OPC_FABRIC ||
3098 						  tqpair->qpair.qid == 0) && tcp_req->req.length > transport->opts.in_capsule_data_size)) {
3099 				tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
3100 				assert(tgroup->control_msg_list);
3101 				SPDK_DEBUGLOG(nvmf_tcp, "Put buf to control msg list\n");
3102 				nvmf_tcp_control_msg_put(tgroup->control_msg_list,
3103 							 tcp_req->req.iov[0].iov_base);
3104 			} else if (tcp_req->req.zcopy_bdev_io != NULL) {
3105 				/* If the request has an unreleased zcopy bdev_io, it's either a
3106 				 * read, a failed write, or the qpair is being disconnected */
3107 				assert(spdk_nvmf_request_using_zcopy(&tcp_req->req));
3108 				assert(tcp_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST ||
3109 				       spdk_nvme_cpl_is_error(&tcp_req->req.rsp->nvme_cpl) ||
3110 				       tqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE);
3111 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE);
3112 				spdk_nvmf_request_zcopy_end(&tcp_req->req, false);
3113 				break;
3114 			}
3115 			tcp_req->req.length = 0;
3116 			tcp_req->req.iovcnt = 0;
3117 			tcp_req->req.data = NULL;
3118 			tcp_req->fused_failed = false;
3119 			if (tcp_req->fused_pair) {
3120 				/* This req was part of a valid fused pair, but failed before it got to
3121 				 * READ_TO_EXECUTE state.  This means we need to fail the other request
3122 				 * in the pair, because it is no longer part of a valid pair.  If the pair
3123 				 * already reached READY_TO_EXECUTE state, we need to kick it.
3124 				 */
3125 				tcp_req->fused_pair->fused_failed = true;
3126 				if (tcp_req->fused_pair->state == TCP_REQUEST_STATE_READY_TO_EXECUTE) {
3127 					nvmf_tcp_req_process(ttransport, tcp_req->fused_pair);
3128 				}
3129 				tcp_req->fused_pair = NULL;
3130 			}
3131 
3132 			nvmf_tcp_req_put(tqpair, tcp_req);
3133 			break;
3134 		case TCP_REQUEST_NUM_STATES:
3135 		default:
3136 			assert(0);
3137 			break;
3138 		}
3139 
3140 		if (tcp_req->state != prev_state) {
3141 			progress = true;
3142 		}
3143 	} while (tcp_req->state != prev_state);
3144 
3145 	return progress;
3146 }
3147 
3148 static void
3149 nvmf_tcp_sock_cb(void *arg, struct spdk_sock_group *group, struct spdk_sock *sock)
3150 {
3151 	struct spdk_nvmf_tcp_qpair *tqpair = arg;
3152 	int rc;
3153 
3154 	assert(tqpair != NULL);
3155 	rc = nvmf_tcp_sock_process(tqpair);
3156 
3157 	/* If there was a new socket error, disconnect */
3158 	if (rc < 0) {
3159 		nvmf_tcp_qpair_disconnect(tqpair);
3160 	}
3161 }
3162 
3163 static int
3164 nvmf_tcp_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
3165 			struct spdk_nvmf_qpair *qpair)
3166 {
3167 	struct spdk_nvmf_tcp_poll_group	*tgroup;
3168 	struct spdk_nvmf_tcp_qpair	*tqpair;
3169 	int				rc;
3170 
3171 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
3172 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3173 
3174 	rc =  nvmf_tcp_qpair_sock_init(tqpair);
3175 	if (rc != 0) {
3176 		SPDK_ERRLOG("Cannot set sock opt for tqpair=%p\n", tqpair);
3177 		return -1;
3178 	}
3179 
3180 	rc = nvmf_tcp_qpair_init(&tqpair->qpair);
3181 	if (rc < 0) {
3182 		SPDK_ERRLOG("Cannot init tqpair=%p\n", tqpair);
3183 		return -1;
3184 	}
3185 
3186 	rc = nvmf_tcp_qpair_init_mem_resource(tqpair);
3187 	if (rc < 0) {
3188 		SPDK_ERRLOG("Cannot init memory resource info for tqpair=%p\n", tqpair);
3189 		return -1;
3190 	}
3191 
3192 	rc = spdk_sock_group_add_sock(tgroup->sock_group, tqpair->sock,
3193 				      nvmf_tcp_sock_cb, tqpair);
3194 	if (rc != 0) {
3195 		SPDK_ERRLOG("Could not add sock to sock_group: %s (%d)\n",
3196 			    spdk_strerror(errno), errno);
3197 		return -1;
3198 	}
3199 
3200 	tqpair->group = tgroup;
3201 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_INVALID);
3202 	TAILQ_INSERT_TAIL(&tgroup->qpairs, tqpair, link);
3203 
3204 	return 0;
3205 }
3206 
3207 static int
3208 nvmf_tcp_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
3209 			   struct spdk_nvmf_qpair *qpair)
3210 {
3211 	struct spdk_nvmf_tcp_poll_group	*tgroup;
3212 	struct spdk_nvmf_tcp_qpair		*tqpair;
3213 	int				rc;
3214 
3215 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
3216 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3217 
3218 	assert(tqpair->group == tgroup);
3219 
3220 	SPDK_DEBUGLOG(nvmf_tcp, "remove tqpair=%p from the tgroup=%p\n", tqpair, tgroup);
3221 	if (tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_REQ) {
3222 		TAILQ_REMOVE(&tgroup->await_req, tqpair, link);
3223 	} else {
3224 		TAILQ_REMOVE(&tgroup->qpairs, tqpair, link);
3225 	}
3226 
3227 	rc = spdk_sock_group_remove_sock(tgroup->sock_group, tqpair->sock);
3228 	if (rc != 0) {
3229 		SPDK_ERRLOG("Could not remove sock from sock_group: %s (%d)\n",
3230 			    spdk_strerror(errno), errno);
3231 	}
3232 
3233 	return rc;
3234 }
3235 
3236 static int
3237 nvmf_tcp_req_complete(struct spdk_nvmf_request *req)
3238 {
3239 	struct spdk_nvmf_tcp_transport *ttransport;
3240 	struct spdk_nvmf_tcp_req *tcp_req;
3241 
3242 	ttransport = SPDK_CONTAINEROF(req->qpair->transport, struct spdk_nvmf_tcp_transport, transport);
3243 	tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
3244 
3245 	switch (tcp_req->state) {
3246 	case TCP_REQUEST_STATE_EXECUTING:
3247 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT:
3248 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTED);
3249 		break;
3250 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_START:
3251 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_ZCOPY_START_COMPLETED);
3252 		break;
3253 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE:
3254 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
3255 		break;
3256 	default:
3257 		assert(0 && "Unexpected request state");
3258 		break;
3259 	}
3260 
3261 	nvmf_tcp_req_process(ttransport, tcp_req);
3262 
3263 	return 0;
3264 }
3265 
3266 static void
3267 nvmf_tcp_close_qpair(struct spdk_nvmf_qpair *qpair,
3268 		     spdk_nvmf_transport_qpair_fini_cb cb_fn, void *cb_arg)
3269 {
3270 	struct spdk_nvmf_tcp_qpair *tqpair;
3271 
3272 	SPDK_DEBUGLOG(nvmf_tcp, "Qpair: %p\n", qpair);
3273 
3274 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3275 
3276 	assert(tqpair->fini_cb_fn == NULL);
3277 	tqpair->fini_cb_fn = cb_fn;
3278 	tqpair->fini_cb_arg = cb_arg;
3279 
3280 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_EXITED);
3281 	nvmf_tcp_qpair_destroy(tqpair);
3282 }
3283 
3284 static int
3285 nvmf_tcp_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3286 {
3287 	struct spdk_nvmf_tcp_poll_group *tgroup;
3288 	int rc;
3289 	struct spdk_nvmf_request *req, *req_tmp;
3290 	struct spdk_nvmf_tcp_req *tcp_req;
3291 	struct spdk_nvmf_tcp_qpair *tqpair, *tqpair_tmp;
3292 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(group->transport,
3293 			struct spdk_nvmf_tcp_transport, transport);
3294 
3295 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
3296 
3297 	if (spdk_unlikely(TAILQ_EMPTY(&tgroup->qpairs) && TAILQ_EMPTY(&tgroup->await_req))) {
3298 		return 0;
3299 	}
3300 
3301 	STAILQ_FOREACH_SAFE(req, &group->pending_buf_queue, buf_link, req_tmp) {
3302 		tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
3303 		if (nvmf_tcp_req_process(ttransport, tcp_req) == false) {
3304 			break;
3305 		}
3306 	}
3307 
3308 	rc = spdk_sock_group_poll(tgroup->sock_group);
3309 	if (rc < 0) {
3310 		SPDK_ERRLOG("Failed to poll sock_group=%p\n", tgroup->sock_group);
3311 	}
3312 
3313 	TAILQ_FOREACH_SAFE(tqpair, &tgroup->await_req, link, tqpair_tmp) {
3314 		rc = nvmf_tcp_sock_process(tqpair);
3315 
3316 		/* If there was a new socket error, disconnect */
3317 		if (rc < 0) {
3318 			nvmf_tcp_qpair_disconnect(tqpair);
3319 		}
3320 	}
3321 
3322 	return rc;
3323 }
3324 
3325 static int
3326 nvmf_tcp_qpair_get_trid(struct spdk_nvmf_qpair *qpair,
3327 			struct spdk_nvme_transport_id *trid, bool peer)
3328 {
3329 	struct spdk_nvmf_tcp_qpair     *tqpair;
3330 	uint16_t			port;
3331 
3332 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3333 	spdk_nvme_trid_populate_transport(trid, SPDK_NVME_TRANSPORT_TCP);
3334 
3335 	if (peer) {
3336 		snprintf(trid->traddr, sizeof(trid->traddr), "%s", tqpair->initiator_addr);
3337 		port = tqpair->initiator_port;
3338 	} else {
3339 		snprintf(trid->traddr, sizeof(trid->traddr), "%s", tqpair->target_addr);
3340 		port = tqpair->target_port;
3341 	}
3342 
3343 	if (spdk_sock_is_ipv4(tqpair->sock)) {
3344 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3345 	} else if (spdk_sock_is_ipv6(tqpair->sock)) {
3346 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3347 	} else {
3348 		return -1;
3349 	}
3350 
3351 	snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%d", port);
3352 	return 0;
3353 }
3354 
3355 static int
3356 nvmf_tcp_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
3357 			      struct spdk_nvme_transport_id *trid)
3358 {
3359 	return nvmf_tcp_qpair_get_trid(qpair, trid, 0);
3360 }
3361 
3362 static int
3363 nvmf_tcp_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
3364 			     struct spdk_nvme_transport_id *trid)
3365 {
3366 	return nvmf_tcp_qpair_get_trid(qpair, trid, 1);
3367 }
3368 
3369 static int
3370 nvmf_tcp_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
3371 			       struct spdk_nvme_transport_id *trid)
3372 {
3373 	return nvmf_tcp_qpair_get_trid(qpair, trid, 0);
3374 }
3375 
3376 static void
3377 nvmf_tcp_req_set_abort_status(struct spdk_nvmf_request *req,
3378 			      struct spdk_nvmf_tcp_req *tcp_req_to_abort)
3379 {
3380 	tcp_req_to_abort->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
3381 	tcp_req_to_abort->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_BY_REQUEST;
3382 	tcp_req_to_abort->req.rsp->nvme_cpl.cid = tcp_req_to_abort->req.cmd->nvme_cmd.cid;
3383 
3384 	nvmf_tcp_req_set_state(tcp_req_to_abort, TCP_REQUEST_STATE_READY_TO_COMPLETE);
3385 
3386 	req->rsp->nvme_cpl.cdw0 &= ~1U; /* Command was successfully aborted. */
3387 }
3388 
3389 static int
3390 _nvmf_tcp_qpair_abort_request(void *ctx)
3391 {
3392 	struct spdk_nvmf_request *req = ctx;
3393 	struct spdk_nvmf_tcp_req *tcp_req_to_abort = SPDK_CONTAINEROF(req->req_to_abort,
3394 			struct spdk_nvmf_tcp_req, req);
3395 	struct spdk_nvmf_tcp_qpair *tqpair = SPDK_CONTAINEROF(req->req_to_abort->qpair,
3396 					     struct spdk_nvmf_tcp_qpair, qpair);
3397 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport,
3398 			struct spdk_nvmf_tcp_transport, transport);
3399 	int rc;
3400 
3401 	spdk_poller_unregister(&req->poller);
3402 
3403 	switch (tcp_req_to_abort->state) {
3404 	case TCP_REQUEST_STATE_EXECUTING:
3405 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_START:
3406 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT:
3407 		rc = nvmf_ctrlr_abort_request(req);
3408 		if (rc == SPDK_NVMF_REQUEST_EXEC_STATUS_ASYNCHRONOUS) {
3409 			return SPDK_POLLER_BUSY;
3410 		}
3411 		break;
3412 
3413 	case TCP_REQUEST_STATE_NEED_BUFFER:
3414 		STAILQ_REMOVE(&tqpair->group->group.pending_buf_queue,
3415 			      &tcp_req_to_abort->req, spdk_nvmf_request, buf_link);
3416 
3417 		nvmf_tcp_req_set_abort_status(req, tcp_req_to_abort);
3418 		nvmf_tcp_req_process(ttransport, tcp_req_to_abort);
3419 		break;
3420 
3421 	case TCP_REQUEST_STATE_AWAITING_R2T_ACK:
3422 	case TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
3423 		if (spdk_get_ticks() < req->timeout_tsc) {
3424 			req->poller = SPDK_POLLER_REGISTER(_nvmf_tcp_qpair_abort_request, req, 0);
3425 			return SPDK_POLLER_BUSY;
3426 		}
3427 		break;
3428 
3429 	default:
3430 		/* Requests in other states are either un-abortable (e.g.
3431 		 * TRANSFERRING_CONTROLLER_TO_HOST) or should never end up here, as they're
3432 		 * immediately transitioned to other states in nvmf_tcp_req_process() (e.g.
3433 		 * READY_TO_EXECUTE).  But it is fine to end up here, as we'll simply complete the
3434 		 * abort request with the bit0 of dword0 set (command not aborted).
3435 		 */
3436 		break;
3437 	}
3438 
3439 	spdk_nvmf_request_complete(req);
3440 	return SPDK_POLLER_BUSY;
3441 }
3442 
3443 static void
3444 nvmf_tcp_qpair_abort_request(struct spdk_nvmf_qpair *qpair,
3445 			     struct spdk_nvmf_request *req)
3446 {
3447 	struct spdk_nvmf_tcp_qpair *tqpair;
3448 	struct spdk_nvmf_tcp_transport *ttransport;
3449 	struct spdk_nvmf_transport *transport;
3450 	uint16_t cid;
3451 	uint32_t i;
3452 	struct spdk_nvmf_tcp_req *tcp_req_to_abort = NULL;
3453 
3454 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3455 	ttransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_tcp_transport, transport);
3456 	transport = &ttransport->transport;
3457 
3458 	cid = req->cmd->nvme_cmd.cdw10_bits.abort.cid;
3459 
3460 	for (i = 0; i < tqpair->resource_count; i++) {
3461 		if (tqpair->reqs[i].state != TCP_REQUEST_STATE_FREE &&
3462 		    tqpair->reqs[i].req.cmd->nvme_cmd.cid == cid) {
3463 			tcp_req_to_abort = &tqpair->reqs[i];
3464 			break;
3465 		}
3466 	}
3467 
3468 	spdk_trace_record(TRACE_TCP_QP_ABORT_REQ, qpair->qid, 0, (uintptr_t)req, tqpair);
3469 
3470 	if (tcp_req_to_abort == NULL) {
3471 		spdk_nvmf_request_complete(req);
3472 		return;
3473 	}
3474 
3475 	req->req_to_abort = &tcp_req_to_abort->req;
3476 	req->timeout_tsc = spdk_get_ticks() +
3477 			   transport->opts.abort_timeout_sec * spdk_get_ticks_hz();
3478 	req->poller = NULL;
3479 
3480 	_nvmf_tcp_qpair_abort_request(req);
3481 }
3482 
3483 struct tcp_subsystem_add_host_opts {
3484 	char *psk;
3485 };
3486 
3487 static const struct spdk_json_object_decoder tcp_subsystem_add_host_opts_decoder[] = {
3488 	{"psk", offsetof(struct tcp_subsystem_add_host_opts, psk), spdk_json_decode_string, true},
3489 };
3490 
3491 static int
3492 nvmf_tcp_subsystem_add_host(struct spdk_nvmf_transport *transport,
3493 			    const struct spdk_nvmf_subsystem *subsystem,
3494 			    const char *hostnqn,
3495 			    const struct spdk_json_val *transport_specific)
3496 {
3497 	struct tcp_subsystem_add_host_opts opts;
3498 	struct spdk_nvmf_tcp_transport *ttransport;
3499 	struct tcp_psk_entry *entry;
3500 	char psk_identity[NVMF_PSK_IDENTITY_LEN];
3501 	uint64_t key_len;
3502 	int rc = 0;
3503 
3504 	if (transport_specific == NULL) {
3505 		return 0;
3506 	}
3507 
3508 	assert(transport != NULL);
3509 	assert(subsystem != NULL);
3510 
3511 	memset(&opts, 0, sizeof(opts));
3512 
3513 	/* Decode PSK */
3514 	if (spdk_json_decode_object_relaxed(transport_specific, tcp_subsystem_add_host_opts_decoder,
3515 					    SPDK_COUNTOF(tcp_subsystem_add_host_opts_decoder), &opts)) {
3516 		SPDK_ERRLOG("spdk_json_decode_object failed\n");
3517 		return -EINVAL;
3518 	}
3519 
3520 	if (opts.psk == NULL) {
3521 		return 0;
3522 	}
3523 
3524 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
3525 	/* Generate PSK identity. */
3526 	rc = nvme_tcp_generate_psk_identity(psk_identity, NVMF_PSK_IDENTITY_LEN, hostnqn,
3527 					    subsystem->subnqn);
3528 	if (rc) {
3529 		rc = -EINVAL;
3530 		goto end;
3531 	}
3532 	/* Check if PSK identity entry already exists. */
3533 	TAILQ_FOREACH(entry, &ttransport->psks, link) {
3534 		if (strncmp(entry->psk_identity, psk_identity, NVMF_PSK_IDENTITY_LEN) == 0) {
3535 			SPDK_ERRLOG("Given PSK identity: %s entry already exists!\n", psk_identity);
3536 			rc = -EEXIST;
3537 			goto end;
3538 		}
3539 	}
3540 	entry = calloc(1, sizeof(struct tcp_psk_entry));
3541 	if (entry == NULL) {
3542 		SPDK_ERRLOG("Unable to allocate memory for PSK entry!\n");
3543 		rc = -ENOMEM;
3544 		goto end;
3545 	}
3546 
3547 	if (snprintf(entry->hostnqn, sizeof(entry->hostnqn), "%s", hostnqn) < 0) {
3548 		SPDK_ERRLOG("Could not write hostnqn string!\n");
3549 		rc = -EINVAL;
3550 		free(entry);
3551 		goto end;
3552 	}
3553 	if (snprintf(entry->subnqn, sizeof(entry->subnqn), "%s", subsystem->subnqn) < 0) {
3554 		SPDK_ERRLOG("Could not write subnqn string!\n");
3555 		rc = -EINVAL;
3556 		free(entry);
3557 		goto end;
3558 	}
3559 	if (snprintf(entry->psk_identity, sizeof(entry->psk_identity), "%s", psk_identity) < 0) {
3560 		SPDK_ERRLOG("Could not write PSK identity string!\n");
3561 		rc = -EINVAL;
3562 		free(entry);
3563 		goto end;
3564 	}
3565 	if (strlen(opts.psk) >= sizeof(entry->psk)) {
3566 		SPDK_ERRLOG("PSK of length: %ld cannot fit in max buffer size: %ld\n", strlen(opts.psk),
3567 			    sizeof(entry->psk));
3568 		rc = -EINVAL;
3569 		free(entry);
3570 		goto end;
3571 	}
3572 
3573 	/* Derive retained PSK. */
3574 	rc = nvme_tcp_derive_retained_psk(opts.psk, hostnqn, entry->psk, SPDK_TLS_PSK_MAX_LEN);
3575 	if (rc < 0) {
3576 		SPDK_ERRLOG("Unable to derive retained PSK!\n");
3577 		goto end;
3578 	}
3579 	entry->psk_size = rc;
3580 
3581 	TAILQ_INSERT_TAIL(&ttransport->psks, entry, link);
3582 	rc = 0;
3583 
3584 end:
3585 	key_len = strnlen(opts.psk, SPDK_TLS_PSK_MAX_LEN);
3586 	spdk_memset_s(opts.psk, key_len, 0, key_len);
3587 	free(opts.psk);
3588 
3589 	return rc;
3590 }
3591 
3592 static void
3593 nvmf_tcp_subsystem_remove_host(struct spdk_nvmf_transport *transport,
3594 			       const struct spdk_nvmf_subsystem *subsystem,
3595 			       const char *hostnqn)
3596 {
3597 	struct spdk_nvmf_tcp_transport *ttransport;
3598 	struct tcp_psk_entry *entry, *tmp;
3599 
3600 	assert(transport != NULL);
3601 	assert(subsystem != NULL);
3602 
3603 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
3604 	TAILQ_FOREACH_SAFE(entry, &ttransport->psks, link, tmp) {
3605 		if ((strncmp(entry->hostnqn, hostnqn, SPDK_NVMF_NQN_MAX_LEN)) == 0 &&
3606 		    (strncmp(entry->subnqn, subsystem->subnqn, SPDK_NVMF_NQN_MAX_LEN)) == 0) {
3607 			TAILQ_REMOVE(&ttransport->psks, entry, link);
3608 			spdk_memset_s(entry->psk, sizeof(entry->psk), 0, sizeof(entry->psk));
3609 			free(entry);
3610 			break;
3611 		}
3612 	}
3613 }
3614 
3615 static void
3616 nvmf_tcp_opts_init(struct spdk_nvmf_transport_opts *opts)
3617 {
3618 	opts->max_queue_depth =		SPDK_NVMF_TCP_DEFAULT_MAX_IO_QUEUE_DEPTH;
3619 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_TCP_DEFAULT_MAX_QPAIRS_PER_CTRLR;
3620 	opts->in_capsule_data_size =	SPDK_NVMF_TCP_DEFAULT_IN_CAPSULE_DATA_SIZE;
3621 	opts->max_io_size =		SPDK_NVMF_TCP_DEFAULT_MAX_IO_SIZE;
3622 	opts->io_unit_size =		SPDK_NVMF_TCP_DEFAULT_IO_UNIT_SIZE;
3623 	opts->max_aq_depth =		SPDK_NVMF_TCP_DEFAULT_MAX_ADMIN_QUEUE_DEPTH;
3624 	opts->num_shared_buffers =	SPDK_NVMF_TCP_DEFAULT_NUM_SHARED_BUFFERS;
3625 	opts->buf_cache_size =		SPDK_NVMF_TCP_DEFAULT_BUFFER_CACHE_SIZE;
3626 	opts->dif_insert_or_strip =	SPDK_NVMF_TCP_DEFAULT_DIF_INSERT_OR_STRIP;
3627 	opts->abort_timeout_sec =	SPDK_NVMF_TCP_DEFAULT_ABORT_TIMEOUT_SEC;
3628 	opts->transport_specific =      NULL;
3629 }
3630 
3631 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_tcp = {
3632 	.name = "TCP",
3633 	.type = SPDK_NVME_TRANSPORT_TCP,
3634 	.opts_init = nvmf_tcp_opts_init,
3635 	.create = nvmf_tcp_create,
3636 	.dump_opts = nvmf_tcp_dump_opts,
3637 	.destroy = nvmf_tcp_destroy,
3638 
3639 	.listen = nvmf_tcp_listen,
3640 	.stop_listen = nvmf_tcp_stop_listen,
3641 
3642 	.listener_discover = nvmf_tcp_discover,
3643 
3644 	.poll_group_create = nvmf_tcp_poll_group_create,
3645 	.get_optimal_poll_group = nvmf_tcp_get_optimal_poll_group,
3646 	.poll_group_destroy = nvmf_tcp_poll_group_destroy,
3647 	.poll_group_add = nvmf_tcp_poll_group_add,
3648 	.poll_group_remove = nvmf_tcp_poll_group_remove,
3649 	.poll_group_poll = nvmf_tcp_poll_group_poll,
3650 
3651 	.req_free = nvmf_tcp_req_free,
3652 	.req_complete = nvmf_tcp_req_complete,
3653 
3654 	.qpair_fini = nvmf_tcp_close_qpair,
3655 	.qpair_get_local_trid = nvmf_tcp_qpair_get_local_trid,
3656 	.qpair_get_peer_trid = nvmf_tcp_qpair_get_peer_trid,
3657 	.qpair_get_listen_trid = nvmf_tcp_qpair_get_listen_trid,
3658 	.qpair_abort_request = nvmf_tcp_qpair_abort_request,
3659 	.subsystem_add_host = nvmf_tcp_subsystem_add_host,
3660 	.subsystem_remove_host = nvmf_tcp_subsystem_remove_host,
3661 };
3662 
3663 SPDK_NVMF_TRANSPORT_REGISTER(tcp, &spdk_nvmf_transport_tcp);
3664 SPDK_LOG_REGISTER_COMPONENT(nvmf_tcp)
3665