xref: /spdk/lib/nvmf/tcp.c (revision 5485f55dc15bde438aee60c460f09d376f93a4fb)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2019, 2020 Mellanox Technologies LTD. All rights reserved.
6  *   Copyright (c) 2022 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
7  *
8  *   Redistribution and use in source and binary forms, with or without
9  *   modification, are permitted provided that the following conditions
10  *   are met:
11  *
12  *     * Redistributions of source code must retain the above copyright
13  *       notice, this list of conditions and the following disclaimer.
14  *     * Redistributions in binary form must reproduce the above copyright
15  *       notice, this list of conditions and the following disclaimer in
16  *       the documentation and/or other materials provided with the
17  *       distribution.
18  *     * Neither the name of Intel Corporation nor the names of its
19  *       contributors may be used to endorse or promote products derived
20  *       from this software without specific prior written permission.
21  *
22  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
25  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
26  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
28  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
32  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include "spdk/accel_engine.h"
36 #include "spdk/stdinc.h"
37 #include "spdk/crc32.h"
38 #include "spdk/endian.h"
39 #include "spdk/assert.h"
40 #include "spdk/thread.h"
41 #include "spdk/nvmf_transport.h"
42 #include "spdk/string.h"
43 #include "spdk/trace.h"
44 #include "spdk/util.h"
45 #include "spdk/log.h"
46 
47 #include "spdk_internal/assert.h"
48 #include "spdk_internal/nvme_tcp.h"
49 #include "spdk_internal/sock.h"
50 
51 #include "nvmf_internal.h"
52 
53 #include "spdk_internal/trace_defs.h"
54 
55 #define NVMF_TCP_MAX_ACCEPT_SOCK_ONE_TIME 16
56 #define SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY 16
57 #define SPDK_NVMF_TCP_DEFAULT_SOCK_PRIORITY 0
58 #define SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM 32
59 #define SPDK_NVMF_TCP_DEFAULT_SUCCESS_OPTIMIZATION true
60 
61 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_tcp;
62 
63 /* spdk nvmf related structure */
64 enum spdk_nvmf_tcp_req_state {
65 
66 	/* The request is not currently in use */
67 	TCP_REQUEST_STATE_FREE = 0,
68 
69 	/* Initial state when request first received */
70 	TCP_REQUEST_STATE_NEW = 1,
71 
72 	/* The request is queued until a data buffer is available. */
73 	TCP_REQUEST_STATE_NEED_BUFFER = 2,
74 
75 	/* The request is waiting for zcopy_start to finish */
76 	TCP_REQUEST_STATE_AWAITING_ZCOPY_START = 3,
77 
78 	/* The request has received a zero-copy buffer */
79 	TCP_REQUEST_STATE_ZCOPY_START_COMPLETED = 4,
80 
81 	/* The request is currently transferring data from the host to the controller. */
82 	TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER = 5,
83 
84 	/* The request is waiting for the R2T send acknowledgement. */
85 	TCP_REQUEST_STATE_AWAITING_R2T_ACK = 6,
86 
87 	/* The request is ready to execute at the block device */
88 	TCP_REQUEST_STATE_READY_TO_EXECUTE = 7,
89 
90 	/* The request is currently executing at the block device */
91 	TCP_REQUEST_STATE_EXECUTING = 8,
92 
93 	/* The request is waiting for zcopy buffers to be commited */
94 	TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT = 9,
95 
96 	/* The request finished executing at the block device */
97 	TCP_REQUEST_STATE_EXECUTED = 10,
98 
99 	/* The request is ready to send a completion */
100 	TCP_REQUEST_STATE_READY_TO_COMPLETE = 11,
101 
102 	/* The request is currently transferring final pdus from the controller to the host. */
103 	TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST = 12,
104 
105 	/* The request is waiting for zcopy buffers to be released (without committing) */
106 	TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE = 13,
107 
108 	/* The request completed and can be marked free. */
109 	TCP_REQUEST_STATE_COMPLETED = 14,
110 
111 	/* Terminator */
112 	TCP_REQUEST_NUM_STATES,
113 };
114 
115 static const char *spdk_nvmf_tcp_term_req_fes_str[] = {
116 	"Invalid PDU Header Field",
117 	"PDU Sequence Error",
118 	"Header Digiest Error",
119 	"Data Transfer Out of Range",
120 	"R2T Limit Exceeded",
121 	"Unsupported parameter",
122 };
123 
124 SPDK_TRACE_REGISTER_FN(nvmf_tcp_trace, "nvmf_tcp", TRACE_GROUP_NVMF_TCP)
125 {
126 	spdk_trace_register_object(OBJECT_NVMF_TCP_IO, 'r');
127 	spdk_trace_register_description("TCP_REQ_NEW",
128 					TRACE_TCP_REQUEST_STATE_NEW,
129 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 1,
130 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
131 	spdk_trace_register_description("TCP_REQ_NEED_BUFFER",
132 					TRACE_TCP_REQUEST_STATE_NEED_BUFFER,
133 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
134 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
135 	spdk_trace_register_description("TCP_REQ_WAIT_ZCPY_START",
136 					TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_START,
137 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
138 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
139 	spdk_trace_register_description("TCP_REQ_ZCPY_START_CPL",
140 					TRACE_TCP_REQUEST_STATE_ZCOPY_START_COMPLETED,
141 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
142 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
143 	spdk_trace_register_description("TCP_REQ_TX_H_TO_C",
144 					TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
145 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
146 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
147 	spdk_trace_register_description("TCP_REQ_RDY_TO_EXECUTE",
148 					TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE,
149 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
150 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
151 	spdk_trace_register_description("TCP_REQ_EXECUTING",
152 					TRACE_TCP_REQUEST_STATE_EXECUTING,
153 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
154 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
155 	spdk_trace_register_description("TCP_REQ_WAIT_ZCPY_CMT",
156 					TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_COMMIT,
157 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
158 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
159 	spdk_trace_register_description("TCP_REQ_EXECUTED",
160 					TRACE_TCP_REQUEST_STATE_EXECUTED,
161 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
162 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
163 	spdk_trace_register_description("TCP_REQ_RDY_TO_COMPLETE",
164 					TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE,
165 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
166 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
167 	spdk_trace_register_description("TCP_REQ_TRANSFER_C2H",
168 					TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
169 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
170 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
171 	spdk_trace_register_description("TCP_REQ_AWAIT_ZCPY_RLS",
172 					TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_RELEASE,
173 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
174 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
175 	spdk_trace_register_description("TCP_REQ_COMPLETED",
176 					TRACE_TCP_REQUEST_STATE_COMPLETED,
177 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
178 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
179 	spdk_trace_register_description("TCP_WRITE_START",
180 					TRACE_TCP_FLUSH_WRITEBUF_START,
181 					OWNER_NONE, OBJECT_NONE, 0,
182 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
183 	spdk_trace_register_description("TCP_WRITE_DONE",
184 					TRACE_TCP_FLUSH_WRITEBUF_DONE,
185 					OWNER_NONE, OBJECT_NONE, 0,
186 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
187 	spdk_trace_register_description("TCP_READ_DONE",
188 					TRACE_TCP_READ_FROM_SOCKET_DONE,
189 					OWNER_NONE, OBJECT_NONE, 0,
190 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
191 	spdk_trace_register_description("TCP_REQ_AWAIT_R2T_ACK",
192 					TRACE_TCP_REQUEST_STATE_AWAIT_R2T_ACK,
193 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0,
194 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
195 
196 	spdk_trace_register_description("TCP_QP_CREATE", TRACE_TCP_QP_CREATE,
197 					OWNER_NONE, OBJECT_NONE, 0,
198 					SPDK_TRACE_ARG_TYPE_INT, "");
199 	spdk_trace_register_description("TCP_QP_SOCK_INIT", TRACE_TCP_QP_SOCK_INIT,
200 					OWNER_NONE, OBJECT_NONE, 0,
201 					SPDK_TRACE_ARG_TYPE_INT, "");
202 	spdk_trace_register_description("TCP_QP_STATE_CHANGE", TRACE_TCP_QP_STATE_CHANGE,
203 					OWNER_NONE, OBJECT_NONE, 0,
204 					SPDK_TRACE_ARG_TYPE_INT, "state");
205 	spdk_trace_register_description("TCP_QP_DISCONNECT", TRACE_TCP_QP_DISCONNECT,
206 					OWNER_NONE, OBJECT_NONE, 0,
207 					SPDK_TRACE_ARG_TYPE_INT, "");
208 	spdk_trace_register_description("TCP_QP_DESTROY", TRACE_TCP_QP_DESTROY,
209 					OWNER_NONE, OBJECT_NONE, 0,
210 					SPDK_TRACE_ARG_TYPE_INT, "");
211 	spdk_trace_register_description("TCP_QP_ABORT_REQ", TRACE_TCP_QP_ABORT_REQ,
212 					OWNER_NONE, OBJECT_NONE, 0,
213 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
214 	spdk_trace_register_description("TCP_QP_RCV_STATE_CHANGE", TRACE_TCP_QP_RCV_STATE_CHANGE,
215 					OWNER_NONE, OBJECT_NONE, 0,
216 					SPDK_TRACE_ARG_TYPE_INT, "state");
217 
218 	spdk_trace_tpoint_register_relation(TRACE_BDEV_IO_START, OBJECT_NVMF_TCP_IO, 1);
219 	spdk_trace_tpoint_register_relation(TRACE_BDEV_IO_DONE, OBJECT_NVMF_TCP_IO, 0);
220 }
221 
222 struct spdk_nvmf_tcp_req  {
223 	struct spdk_nvmf_request		req;
224 	struct spdk_nvme_cpl			rsp;
225 	struct spdk_nvme_cmd			cmd;
226 
227 	/* A PDU that can be used for sending responses. This is
228 	 * not the incoming PDU! */
229 	struct nvme_tcp_pdu			*pdu;
230 
231 	/* In-capsule data buffer */
232 	uint8_t					*buf;
233 	/*
234 	 * The PDU for a request may be used multiple times in serial over
235 	 * the request's lifetime. For example, first to send an R2T, then
236 	 * to send a completion. To catch mistakes where the PDU is used
237 	 * twice at the same time, add a debug flag here for init/fini.
238 	 */
239 	bool					pdu_in_use;
240 	bool					has_in_capsule_data;
241 
242 	/* transfer_tag */
243 	uint16_t				ttag;
244 
245 	enum spdk_nvmf_tcp_req_state		state;
246 
247 	/*
248 	 * h2c_offset is used when we receive the h2c_data PDU.
249 	 */
250 	uint32_t				h2c_offset;
251 
252 	STAILQ_ENTRY(spdk_nvmf_tcp_req)		link;
253 	TAILQ_ENTRY(spdk_nvmf_tcp_req)		state_link;
254 };
255 
256 struct spdk_nvmf_tcp_qpair {
257 	struct spdk_nvmf_qpair			qpair;
258 	struct spdk_nvmf_tcp_poll_group		*group;
259 	struct spdk_sock			*sock;
260 
261 	enum nvme_tcp_pdu_recv_state		recv_state;
262 	enum nvme_tcp_qpair_state		state;
263 
264 	/* PDU being actively received */
265 	struct nvme_tcp_pdu			*pdu_in_progress;
266 
267 	/* Queues to track the requests in all states */
268 	TAILQ_HEAD(, spdk_nvmf_tcp_req)		tcp_req_working_queue;
269 	TAILQ_HEAD(, spdk_nvmf_tcp_req)		tcp_req_free_queue;
270 
271 	/* Number of requests in each state */
272 	uint32_t				state_cntr[TCP_REQUEST_NUM_STATES];
273 
274 	uint8_t					cpda;
275 
276 	bool					host_hdgst_enable;
277 	bool					host_ddgst_enable;
278 
279 	/* This is a spare PDU used for sending special management
280 	 * operations. Primarily, this is used for the initial
281 	 * connection response and c2h termination request. */
282 	struct nvme_tcp_pdu			*mgmt_pdu;
283 
284 	/* Arrays of in-capsule buffers, requests, and pdus.
285 	 * Each array is 'resource_count' number of elements */
286 	void					*bufs;
287 	struct spdk_nvmf_tcp_req		*reqs;
288 	struct nvme_tcp_pdu			*pdus;
289 	uint32_t				resource_count;
290 	uint32_t				recv_buf_size;
291 
292 	struct spdk_nvmf_tcp_port		*port;
293 
294 	/* IP address */
295 	char					initiator_addr[SPDK_NVMF_TRADDR_MAX_LEN];
296 	char					target_addr[SPDK_NVMF_TRADDR_MAX_LEN];
297 
298 	/* IP port */
299 	uint16_t				initiator_port;
300 	uint16_t				target_port;
301 
302 	/* Timer used to destroy qpair after detecting transport error issue if initiator does
303 	 *  not close the connection.
304 	 */
305 	struct spdk_poller			*timeout_poller;
306 
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 spdk_nvmf_tcp_transport {
346 	struct spdk_nvmf_transport		transport;
347 	struct tcp_transport_opts               tcp_opts;
348 
349 	struct spdk_nvmf_tcp_poll_group		*next_pg;
350 
351 	struct spdk_poller			*accept_poller;
352 	pthread_mutex_t				lock;
353 
354 	TAILQ_HEAD(, spdk_nvmf_tcp_port)	ports;
355 	TAILQ_HEAD(, spdk_nvmf_tcp_poll_group)	poll_groups;
356 };
357 
358 static const struct spdk_json_object_decoder tcp_transport_opts_decoder[] = {
359 	{
360 		"c2h_success", offsetof(struct tcp_transport_opts, c2h_success),
361 		spdk_json_decode_bool, true
362 	},
363 	{
364 		"control_msg_num", offsetof(struct tcp_transport_opts, control_msg_num),
365 		spdk_json_decode_uint16, true
366 	},
367 	{
368 		"sock_priority", offsetof(struct tcp_transport_opts, sock_priority),
369 		spdk_json_decode_uint32, true
370 	},
371 };
372 
373 static bool nvmf_tcp_req_process(struct spdk_nvmf_tcp_transport *ttransport,
374 				 struct spdk_nvmf_tcp_req *tcp_req);
375 static void nvmf_tcp_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
376 
377 static void _nvmf_tcp_send_c2h_data(struct spdk_nvmf_tcp_qpair *tqpair,
378 				    struct spdk_nvmf_tcp_req *tcp_req);
379 
380 static void
381 nvmf_tcp_req_set_state(struct spdk_nvmf_tcp_req *tcp_req,
382 		       enum spdk_nvmf_tcp_req_state state)
383 {
384 	struct spdk_nvmf_qpair *qpair;
385 	struct spdk_nvmf_tcp_qpair *tqpair;
386 
387 	qpair = tcp_req->req.qpair;
388 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
389 
390 	assert(tqpair->state_cntr[tcp_req->state] > 0);
391 	tqpair->state_cntr[tcp_req->state]--;
392 	tqpair->state_cntr[state]++;
393 
394 	tcp_req->state = state;
395 }
396 
397 static inline struct nvme_tcp_pdu *
398 nvmf_tcp_req_pdu_init(struct spdk_nvmf_tcp_req *tcp_req)
399 {
400 	assert(tcp_req->pdu_in_use == false);
401 	tcp_req->pdu_in_use = true;
402 
403 	memset(tcp_req->pdu, 0, sizeof(*tcp_req->pdu));
404 	tcp_req->pdu->qpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
405 
406 	return tcp_req->pdu;
407 }
408 
409 static inline void
410 nvmf_tcp_req_pdu_fini(struct spdk_nvmf_tcp_req *tcp_req)
411 {
412 	tcp_req->pdu_in_use = false;
413 }
414 
415 static struct spdk_nvmf_tcp_req *
416 nvmf_tcp_req_get(struct spdk_nvmf_tcp_qpair *tqpair)
417 {
418 	struct spdk_nvmf_tcp_req *tcp_req;
419 
420 	tcp_req = TAILQ_FIRST(&tqpair->tcp_req_free_queue);
421 	if (!tcp_req) {
422 		return NULL;
423 	}
424 
425 	memset(&tcp_req->rsp, 0, sizeof(tcp_req->rsp));
426 	tcp_req->h2c_offset = 0;
427 	tcp_req->has_in_capsule_data = false;
428 	tcp_req->req.dif_enabled = false;
429 	tcp_req->req.zcopy_phase = NVMF_ZCOPY_PHASE_NONE;
430 
431 	TAILQ_REMOVE(&tqpair->tcp_req_free_queue, tcp_req, state_link);
432 	TAILQ_INSERT_TAIL(&tqpair->tcp_req_working_queue, tcp_req, state_link);
433 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEW);
434 	return tcp_req;
435 }
436 
437 static inline void
438 nvmf_tcp_req_put(struct spdk_nvmf_tcp_qpair *tqpair, struct spdk_nvmf_tcp_req *tcp_req)
439 {
440 	TAILQ_REMOVE(&tqpair->tcp_req_working_queue, tcp_req, state_link);
441 	TAILQ_INSERT_TAIL(&tqpair->tcp_req_free_queue, tcp_req, state_link);
442 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_FREE);
443 }
444 
445 static void
446 nvmf_tcp_request_free(void *cb_arg)
447 {
448 	struct spdk_nvmf_tcp_transport *ttransport;
449 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
450 
451 	assert(tcp_req != NULL);
452 
453 	SPDK_DEBUGLOG(nvmf_tcp, "tcp_req=%p will be freed\n", tcp_req);
454 	ttransport = SPDK_CONTAINEROF(tcp_req->req.qpair->transport,
455 				      struct spdk_nvmf_tcp_transport, transport);
456 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
457 	nvmf_tcp_req_process(ttransport, tcp_req);
458 }
459 
460 static int
461 nvmf_tcp_req_free(struct spdk_nvmf_request *req)
462 {
463 	struct spdk_nvmf_tcp_req *tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
464 
465 	nvmf_tcp_request_free(tcp_req);
466 
467 	return 0;
468 }
469 
470 static void
471 nvmf_tcp_drain_state_queue(struct spdk_nvmf_tcp_qpair *tqpair,
472 			   enum spdk_nvmf_tcp_req_state state)
473 {
474 	struct spdk_nvmf_tcp_req *tcp_req, *req_tmp;
475 
476 	assert(state != TCP_REQUEST_STATE_FREE);
477 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->tcp_req_working_queue, state_link, req_tmp) {
478 		if (state == tcp_req->state) {
479 			nvmf_tcp_request_free(tcp_req);
480 		}
481 	}
482 }
483 
484 static void
485 nvmf_tcp_cleanup_all_states(struct spdk_nvmf_tcp_qpair *tqpair)
486 {
487 	struct spdk_nvmf_tcp_req *tcp_req, *req_tmp;
488 
489 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST);
490 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_NEW);
491 
492 	/* Wipe the requests waiting for buffer from the global list */
493 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->tcp_req_working_queue, state_link, req_tmp) {
494 		if (tcp_req->state == TCP_REQUEST_STATE_NEED_BUFFER) {
495 			STAILQ_REMOVE(&tqpair->group->group.pending_buf_queue, &tcp_req->req,
496 				      spdk_nvmf_request, buf_link);
497 		}
498 	}
499 
500 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_NEED_BUFFER);
501 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_EXECUTING);
502 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
503 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_AWAITING_R2T_ACK);
504 }
505 
506 static void
507 nvmf_tcp_dump_qpair_req_contents(struct spdk_nvmf_tcp_qpair *tqpair)
508 {
509 	int i;
510 	struct spdk_nvmf_tcp_req *tcp_req;
511 
512 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", tqpair->qpair.qid);
513 	for (i = 1; i < TCP_REQUEST_NUM_STATES; i++) {
514 		SPDK_ERRLOG("\tNum of requests in state[%d] = %u\n", i, tqpair->state_cntr[i]);
515 		TAILQ_FOREACH(tcp_req, &tqpair->tcp_req_working_queue, state_link) {
516 			if ((int)tcp_req->state == i) {
517 				SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", tcp_req->req.data_from_pool);
518 				SPDK_ERRLOG("\t\tRequest opcode: %d\n", tcp_req->req.cmd->nvmf_cmd.opcode);
519 			}
520 		}
521 	}
522 }
523 
524 static void
525 nvmf_tcp_qpair_destroy(struct spdk_nvmf_tcp_qpair *tqpair)
526 {
527 	int err = 0;
528 
529 	spdk_trace_record(TRACE_TCP_QP_DESTROY, 0, 0, (uintptr_t)tqpair);
530 
531 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
532 
533 	err = spdk_sock_close(&tqpair->sock);
534 	assert(err == 0);
535 	nvmf_tcp_cleanup_all_states(tqpair);
536 
537 	if (tqpair->state_cntr[TCP_REQUEST_STATE_FREE] != tqpair->resource_count) {
538 		SPDK_ERRLOG("tqpair(%p) free tcp request num is %u but should be %u\n", tqpair,
539 			    tqpair->state_cntr[TCP_REQUEST_STATE_FREE],
540 			    tqpair->resource_count);
541 		err++;
542 	}
543 
544 	if (err > 0) {
545 		nvmf_tcp_dump_qpair_req_contents(tqpair);
546 	}
547 
548 	spdk_dma_free(tqpair->pdus);
549 	free(tqpair->reqs);
550 	spdk_free(tqpair->bufs);
551 	free(tqpair);
552 	SPDK_DEBUGLOG(nvmf_tcp, "Leave\n");
553 }
554 
555 static void
556 nvmf_tcp_dump_opts(struct spdk_nvmf_transport *transport, struct spdk_json_write_ctx *w)
557 {
558 	struct spdk_nvmf_tcp_transport	*ttransport;
559 	assert(w != NULL);
560 
561 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
562 	spdk_json_write_named_bool(w, "c2h_success", ttransport->tcp_opts.c2h_success);
563 	spdk_json_write_named_uint32(w, "sock_priority", ttransport->tcp_opts.sock_priority);
564 }
565 
566 static int
567 nvmf_tcp_destroy(struct spdk_nvmf_transport *transport,
568 		 spdk_nvmf_transport_destroy_done_cb cb_fn, void *cb_arg)
569 {
570 	struct spdk_nvmf_tcp_transport	*ttransport;
571 
572 	assert(transport != NULL);
573 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
574 
575 	spdk_poller_unregister(&ttransport->accept_poller);
576 	pthread_mutex_destroy(&ttransport->lock);
577 	free(ttransport);
578 
579 	if (cb_fn) {
580 		cb_fn(cb_arg);
581 	}
582 	return 0;
583 }
584 
585 static int
586 nvmf_tcp_accept(void *ctx);
587 
588 static struct spdk_nvmf_transport *
589 nvmf_tcp_create(struct spdk_nvmf_transport_opts *opts)
590 {
591 	struct spdk_nvmf_tcp_transport *ttransport;
592 	uint32_t sge_count;
593 	uint32_t min_shared_buffers;
594 
595 	ttransport = calloc(1, sizeof(*ttransport));
596 	if (!ttransport) {
597 		return NULL;
598 	}
599 
600 	TAILQ_INIT(&ttransport->ports);
601 	TAILQ_INIT(&ttransport->poll_groups);
602 
603 	ttransport->transport.ops = &spdk_nvmf_transport_tcp;
604 
605 	ttransport->tcp_opts.c2h_success = SPDK_NVMF_TCP_DEFAULT_SUCCESS_OPTIMIZATION;
606 	ttransport->tcp_opts.sock_priority = SPDK_NVMF_TCP_DEFAULT_SOCK_PRIORITY;
607 	ttransport->tcp_opts.control_msg_num = SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM;
608 	if (opts->transport_specific != NULL &&
609 	    spdk_json_decode_object_relaxed(opts->transport_specific, tcp_transport_opts_decoder,
610 					    SPDK_COUNTOF(tcp_transport_opts_decoder),
611 					    &ttransport->tcp_opts)) {
612 		SPDK_ERRLOG("spdk_json_decode_object_relaxed failed\n");
613 		free(ttransport);
614 		return NULL;
615 	}
616 
617 	SPDK_NOTICELOG("*** TCP Transport Init ***\n");
618 
619 	SPDK_INFOLOG(nvmf_tcp, "*** TCP Transport Init ***\n"
620 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
621 		     "  max_io_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
622 		     "  in_capsule_data_size=%d, max_aq_depth=%d\n"
623 		     "  num_shared_buffers=%d, c2h_success=%d,\n"
624 		     "  dif_insert_or_strip=%d, sock_priority=%d\n"
625 		     "  abort_timeout_sec=%d, control_msg_num=%hu\n",
626 		     opts->max_queue_depth,
627 		     opts->max_io_size,
628 		     opts->max_qpairs_per_ctrlr - 1,
629 		     opts->io_unit_size,
630 		     opts->in_capsule_data_size,
631 		     opts->max_aq_depth,
632 		     opts->num_shared_buffers,
633 		     ttransport->tcp_opts.c2h_success,
634 		     opts->dif_insert_or_strip,
635 		     ttransport->tcp_opts.sock_priority,
636 		     opts->abort_timeout_sec,
637 		     ttransport->tcp_opts.control_msg_num);
638 
639 	if (ttransport->tcp_opts.sock_priority > SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY) {
640 		SPDK_ERRLOG("Unsupported socket_priority=%d, the current range is: 0 to %d\n"
641 			    "you can use man 7 socket to view the range of priority under SO_PRIORITY item\n",
642 			    ttransport->tcp_opts.sock_priority, SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY);
643 		free(ttransport);
644 		return NULL;
645 	}
646 
647 	if (ttransport->tcp_opts.control_msg_num == 0 &&
648 	    opts->in_capsule_data_size < SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE) {
649 		SPDK_WARNLOG("TCP param control_msg_num can't be 0 if ICD is less than %u bytes. Using default value %u\n",
650 			     SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE, SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM);
651 		ttransport->tcp_opts.control_msg_num = SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM;
652 	}
653 
654 	/* I/O unit size cannot be larger than max I/O size */
655 	if (opts->io_unit_size > opts->max_io_size) {
656 		opts->io_unit_size = opts->max_io_size;
657 	}
658 
659 	sge_count = opts->max_io_size / opts->io_unit_size;
660 	if (sge_count > SPDK_NVMF_MAX_SGL_ENTRIES) {
661 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
662 		free(ttransport);
663 		return NULL;
664 	}
665 
666 	min_shared_buffers = spdk_env_get_core_count() * opts->buf_cache_size;
667 	if (min_shared_buffers > opts->num_shared_buffers) {
668 		SPDK_ERRLOG("There are not enough buffers to satisfy "
669 			    "per-poll group caches for each thread. (%" PRIu32 ") "
670 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
671 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
672 		free(ttransport);
673 		return NULL;
674 	}
675 
676 	pthread_mutex_init(&ttransport->lock, NULL);
677 
678 	ttransport->accept_poller = SPDK_POLLER_REGISTER(nvmf_tcp_accept, &ttransport->transport,
679 				    opts->acceptor_poll_rate);
680 	if (!ttransport->accept_poller) {
681 		pthread_mutex_destroy(&ttransport->lock);
682 		free(ttransport);
683 		return NULL;
684 	}
685 
686 	return &ttransport->transport;
687 }
688 
689 static int
690 nvmf_tcp_trsvcid_to_int(const char *trsvcid)
691 {
692 	unsigned long long ull;
693 	char *end = NULL;
694 
695 	ull = strtoull(trsvcid, &end, 10);
696 	if (end == NULL || end == trsvcid || *end != '\0') {
697 		return -1;
698 	}
699 
700 	/* Valid TCP/IP port numbers are in [0, 65535] */
701 	if (ull > 65535) {
702 		return -1;
703 	}
704 
705 	return (int)ull;
706 }
707 
708 /**
709  * Canonicalize a listen address trid.
710  */
711 static int
712 nvmf_tcp_canon_listen_trid(struct spdk_nvme_transport_id *canon_trid,
713 			   const struct spdk_nvme_transport_id *trid)
714 {
715 	int trsvcid_int;
716 
717 	trsvcid_int = nvmf_tcp_trsvcid_to_int(trid->trsvcid);
718 	if (trsvcid_int < 0) {
719 		return -EINVAL;
720 	}
721 
722 	memset(canon_trid, 0, sizeof(*canon_trid));
723 	spdk_nvme_trid_populate_transport(canon_trid, SPDK_NVME_TRANSPORT_TCP);
724 	canon_trid->adrfam = trid->adrfam;
725 	snprintf(canon_trid->traddr, sizeof(canon_trid->traddr), "%s", trid->traddr);
726 	snprintf(canon_trid->trsvcid, sizeof(canon_trid->trsvcid), "%d", trsvcid_int);
727 
728 	return 0;
729 }
730 
731 /**
732  * Find an existing listening port.
733  *
734  * Caller must hold ttransport->lock.
735  */
736 static struct spdk_nvmf_tcp_port *
737 nvmf_tcp_find_port(struct spdk_nvmf_tcp_transport *ttransport,
738 		   const struct spdk_nvme_transport_id *trid)
739 {
740 	struct spdk_nvme_transport_id canon_trid;
741 	struct spdk_nvmf_tcp_port *port;
742 
743 	if (nvmf_tcp_canon_listen_trid(&canon_trid, trid) != 0) {
744 		return NULL;
745 	}
746 
747 	TAILQ_FOREACH(port, &ttransport->ports, link) {
748 		if (spdk_nvme_transport_id_compare(&canon_trid, port->trid) == 0) {
749 			return port;
750 		}
751 	}
752 
753 	return NULL;
754 }
755 
756 static int
757 nvmf_tcp_listen(struct spdk_nvmf_transport *transport, const struct spdk_nvme_transport_id *trid,
758 		struct spdk_nvmf_listen_opts *listen_opts)
759 {
760 	struct spdk_nvmf_tcp_transport *ttransport;
761 	struct spdk_nvmf_tcp_port *port;
762 	int trsvcid_int;
763 	uint8_t adrfam;
764 	struct spdk_sock_opts opts;
765 
766 	if (!strlen(trid->trsvcid)) {
767 		SPDK_ERRLOG("Service id is required\n");
768 		return -EINVAL;
769 	}
770 
771 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
772 
773 	trsvcid_int = nvmf_tcp_trsvcid_to_int(trid->trsvcid);
774 	if (trsvcid_int < 0) {
775 		SPDK_ERRLOG("Invalid trsvcid '%s'\n", trid->trsvcid);
776 		return -EINVAL;
777 	}
778 
779 	pthread_mutex_lock(&ttransport->lock);
780 	port = calloc(1, sizeof(*port));
781 	if (!port) {
782 		SPDK_ERRLOG("Port allocation failed\n");
783 		pthread_mutex_unlock(&ttransport->lock);
784 		return -ENOMEM;
785 	}
786 
787 	port->trid = trid;
788 	opts.opts_size = sizeof(opts);
789 	spdk_sock_get_default_opts(&opts);
790 	opts.priority = ttransport->tcp_opts.sock_priority;
791 	port->listen_sock = spdk_sock_listen_ext(trid->traddr, trsvcid_int,
792 			    NULL, &opts);
793 	if (port->listen_sock == NULL) {
794 		SPDK_ERRLOG("spdk_sock_listen(%s, %d) failed: %s (%d)\n",
795 			    trid->traddr, trsvcid_int,
796 			    spdk_strerror(errno), errno);
797 		free(port);
798 		pthread_mutex_unlock(&ttransport->lock);
799 		return -errno;
800 	}
801 
802 	if (spdk_sock_is_ipv4(port->listen_sock)) {
803 		adrfam = SPDK_NVMF_ADRFAM_IPV4;
804 	} else if (spdk_sock_is_ipv6(port->listen_sock)) {
805 		adrfam = SPDK_NVMF_ADRFAM_IPV6;
806 	} else {
807 		SPDK_ERRLOG("Unhandled socket type\n");
808 		adrfam = 0;
809 	}
810 
811 	if (adrfam != trid->adrfam) {
812 		SPDK_ERRLOG("Socket address family mismatch\n");
813 		spdk_sock_close(&port->listen_sock);
814 		free(port);
815 		pthread_mutex_unlock(&ttransport->lock);
816 		return -EINVAL;
817 	}
818 
819 	SPDK_NOTICELOG("*** NVMe/TCP Target Listening on %s port %s ***\n",
820 		       trid->traddr, trid->trsvcid);
821 
822 	TAILQ_INSERT_TAIL(&ttransport->ports, port, link);
823 	pthread_mutex_unlock(&ttransport->lock);
824 	return 0;
825 }
826 
827 static void
828 nvmf_tcp_stop_listen(struct spdk_nvmf_transport *transport,
829 		     const struct spdk_nvme_transport_id *trid)
830 {
831 	struct spdk_nvmf_tcp_transport *ttransport;
832 	struct spdk_nvmf_tcp_port *port;
833 
834 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
835 
836 	SPDK_DEBUGLOG(nvmf_tcp, "Removing listen address %s port %s\n",
837 		      trid->traddr, trid->trsvcid);
838 
839 	pthread_mutex_lock(&ttransport->lock);
840 	port = nvmf_tcp_find_port(ttransport, trid);
841 	if (port) {
842 		TAILQ_REMOVE(&ttransport->ports, port, link);
843 		spdk_sock_close(&port->listen_sock);
844 		free(port);
845 	}
846 
847 	pthread_mutex_unlock(&ttransport->lock);
848 }
849 
850 static void nvmf_tcp_qpair_set_recv_state(struct spdk_nvmf_tcp_qpair *tqpair,
851 		enum nvme_tcp_pdu_recv_state state);
852 
853 static void
854 nvmf_tcp_qpair_set_state(struct spdk_nvmf_tcp_qpair *tqpair, enum nvme_tcp_qpair_state state)
855 {
856 	tqpair->state = state;
857 	spdk_trace_record(TRACE_TCP_QP_STATE_CHANGE, 0, 0, (uintptr_t)tqpair, tqpair->state);
858 }
859 
860 static void
861 nvmf_tcp_qpair_disconnect(struct spdk_nvmf_tcp_qpair *tqpair)
862 {
863 	SPDK_DEBUGLOG(nvmf_tcp, "Disconnecting qpair %p\n", tqpair);
864 
865 	spdk_trace_record(TRACE_TCP_QP_DISCONNECT, 0, 0, (uintptr_t)tqpair);
866 
867 	if (tqpair->state <= NVME_TCP_QPAIR_STATE_RUNNING) {
868 		nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_EXITING);
869 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
870 		spdk_poller_unregister(&tqpair->timeout_poller);
871 
872 		/* This will end up calling nvmf_tcp_close_qpair */
873 		spdk_nvmf_qpair_disconnect(&tqpair->qpair, NULL, NULL);
874 	}
875 }
876 
877 static void
878 _pdu_write_done(void *_pdu, int err)
879 {
880 	struct nvme_tcp_pdu			*pdu = _pdu;
881 	struct spdk_nvmf_tcp_qpair		*tqpair = pdu->qpair;
882 
883 	if (err != 0) {
884 		nvmf_tcp_qpair_disconnect(tqpair);
885 		return;
886 	}
887 
888 	assert(pdu->cb_fn != NULL);
889 	pdu->cb_fn(pdu->cb_arg);
890 }
891 
892 static void
893 _tcp_write_pdu(struct nvme_tcp_pdu *pdu)
894 {
895 	uint32_t mapped_length = 0;
896 	ssize_t rc;
897 	struct spdk_nvmf_tcp_qpair *tqpair = pdu->qpair;
898 
899 	pdu->sock_req.iovcnt = nvme_tcp_build_iovs(pdu->iov, SPDK_COUNTOF(pdu->iov), pdu,
900 			       tqpair->host_hdgst_enable, tqpair->host_ddgst_enable,
901 			       &mapped_length);
902 	pdu->sock_req.cb_fn = _pdu_write_done;
903 	pdu->sock_req.cb_arg = pdu;
904 	if (pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_RESP ||
905 	    pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ) {
906 		rc = spdk_sock_writev(tqpair->sock, pdu->iov, pdu->sock_req.iovcnt);
907 		if (rc == mapped_length) {
908 			_pdu_write_done(pdu, 0);
909 		} else {
910 			SPDK_ERRLOG("IC_RESP or TERM_REQ could not write to socket.\n");
911 			_pdu_write_done(pdu, -1);
912 		}
913 	} else {
914 		spdk_sock_writev_async(tqpair->sock, &pdu->sock_req);
915 	}
916 }
917 
918 static void
919 data_crc32_accel_done(void *cb_arg, int status)
920 {
921 	struct nvme_tcp_pdu *pdu = cb_arg;
922 
923 	if (spdk_unlikely(status)) {
924 		SPDK_ERRLOG("Failed to compute the data digest for pdu =%p\n", pdu);
925 		_pdu_write_done(pdu, status);
926 		return;
927 	}
928 
929 	pdu->data_digest_crc32 ^= SPDK_CRC32C_XOR;
930 	MAKE_DIGEST_WORD(pdu->data_digest, pdu->data_digest_crc32);
931 
932 	_tcp_write_pdu(pdu);
933 }
934 
935 static void
936 pdu_data_crc32_compute(struct nvme_tcp_pdu *pdu)
937 {
938 	struct spdk_nvmf_tcp_qpair *tqpair = pdu->qpair;
939 	uint32_t crc32c;
940 
941 	/* Data Digest */
942 	if (pdu->data_len > 0 && g_nvme_tcp_ddgst[pdu->hdr.common.pdu_type] && tqpair->host_ddgst_enable) {
943 		/* Only suport this limitated case for the first step */
944 		if (spdk_likely(!pdu->dif_ctx && (pdu->data_len % SPDK_NVME_TCP_DIGEST_ALIGNMENT == 0)
945 				&& tqpair->group)) {
946 			spdk_accel_submit_crc32cv(tqpair->group->accel_channel, &pdu->data_digest_crc32,
947 						  pdu->data_iov, pdu->data_iovcnt, 0, data_crc32_accel_done, pdu);
948 			return;
949 		}
950 
951 		crc32c = nvme_tcp_pdu_calc_data_digest(pdu);
952 		MAKE_DIGEST_WORD(pdu->data_digest, crc32c);
953 	}
954 
955 	_tcp_write_pdu(pdu);
956 }
957 
958 static void
959 nvmf_tcp_qpair_write_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
960 			 struct nvme_tcp_pdu *pdu,
961 			 nvme_tcp_qpair_xfer_complete_cb cb_fn,
962 			 void *cb_arg)
963 {
964 	int hlen;
965 	uint32_t crc32c;
966 
967 	assert(tqpair->pdu_in_progress != pdu);
968 
969 	hlen = pdu->hdr.common.hlen;
970 	pdu->cb_fn = cb_fn;
971 	pdu->cb_arg = cb_arg;
972 
973 	pdu->iov[0].iov_base = &pdu->hdr.raw;
974 	pdu->iov[0].iov_len = hlen;
975 
976 	/* Header Digest */
977 	if (g_nvme_tcp_hdgst[pdu->hdr.common.pdu_type] && tqpair->host_hdgst_enable) {
978 		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
979 		MAKE_DIGEST_WORD((uint8_t *)pdu->hdr.raw + hlen, crc32c);
980 	}
981 
982 	/* Data Digest */
983 	pdu_data_crc32_compute(pdu);
984 }
985 
986 static int
987 nvmf_tcp_qpair_init_mem_resource(struct spdk_nvmf_tcp_qpair *tqpair)
988 {
989 	uint32_t i;
990 	struct spdk_nvmf_transport_opts *opts;
991 	uint32_t in_capsule_data_size;
992 
993 	opts = &tqpair->qpair.transport->opts;
994 
995 	in_capsule_data_size = opts->in_capsule_data_size;
996 	if (opts->dif_insert_or_strip) {
997 		in_capsule_data_size = SPDK_BDEV_BUF_SIZE_WITH_MD(in_capsule_data_size);
998 	}
999 
1000 	tqpair->resource_count = opts->max_queue_depth;
1001 
1002 	tqpair->reqs = calloc(tqpair->resource_count, sizeof(*tqpair->reqs));
1003 	if (!tqpair->reqs) {
1004 		SPDK_ERRLOG("Unable to allocate reqs on tqpair=%p\n", tqpair);
1005 		return -1;
1006 	}
1007 
1008 	if (in_capsule_data_size) {
1009 		tqpair->bufs = spdk_zmalloc(tqpair->resource_count * in_capsule_data_size, 0x1000,
1010 					    NULL, SPDK_ENV_LCORE_ID_ANY,
1011 					    SPDK_MALLOC_DMA);
1012 		if (!tqpair->bufs) {
1013 			SPDK_ERRLOG("Unable to allocate bufs on tqpair=%p.\n", tqpair);
1014 			return -1;
1015 		}
1016 	}
1017 
1018 	/* Add additional 2 members, which will be used for mgmt_pdu and pdu_in_progress owned by the tqpair */
1019 	tqpair->pdus = spdk_dma_zmalloc((tqpair->resource_count + 2) * sizeof(*tqpair->pdus), 0x1000, NULL);
1020 	if (!tqpair->pdus) {
1021 		SPDK_ERRLOG("Unable to allocate pdu pool on tqpair =%p.\n", tqpair);
1022 		return -1;
1023 	}
1024 
1025 	for (i = 0; i < tqpair->resource_count; i++) {
1026 		struct spdk_nvmf_tcp_req *tcp_req = &tqpair->reqs[i];
1027 
1028 		tcp_req->ttag = i + 1;
1029 		tcp_req->req.qpair = &tqpair->qpair;
1030 
1031 		tcp_req->pdu = &tqpair->pdus[i];
1032 		tcp_req->pdu->qpair = tqpair;
1033 
1034 		/* Set up memory to receive commands */
1035 		if (tqpair->bufs) {
1036 			tcp_req->buf = (void *)((uintptr_t)tqpair->bufs + (i * in_capsule_data_size));
1037 		}
1038 
1039 		/* Set the cmdn and rsp */
1040 		tcp_req->req.rsp = (union nvmf_c2h_msg *)&tcp_req->rsp;
1041 		tcp_req->req.cmd = (union nvmf_h2c_msg *)&tcp_req->cmd;
1042 
1043 		/* Initialize request state to FREE */
1044 		tcp_req->state = TCP_REQUEST_STATE_FREE;
1045 		TAILQ_INSERT_TAIL(&tqpair->tcp_req_free_queue, tcp_req, state_link);
1046 		tqpair->state_cntr[TCP_REQUEST_STATE_FREE]++;
1047 	}
1048 
1049 	tqpair->mgmt_pdu = &tqpair->pdus[i];
1050 	tqpair->mgmt_pdu->qpair = tqpair;
1051 	tqpair->pdu_in_progress = &tqpair->pdus[i + 1];
1052 
1053 	tqpair->recv_buf_size = (in_capsule_data_size + sizeof(struct spdk_nvme_tcp_cmd) + 2 *
1054 				 SPDK_NVME_TCP_DIGEST_LEN) * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
1055 
1056 	return 0;
1057 }
1058 
1059 static int
1060 nvmf_tcp_qpair_init(struct spdk_nvmf_qpair *qpair)
1061 {
1062 	struct spdk_nvmf_tcp_qpair *tqpair;
1063 
1064 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
1065 
1066 	SPDK_DEBUGLOG(nvmf_tcp, "New TCP Connection: %p\n", qpair);
1067 
1068 	spdk_trace_record(TRACE_TCP_QP_CREATE, 0, 0, (uintptr_t)tqpair);
1069 
1070 	/* Initialise request state queues of the qpair */
1071 	TAILQ_INIT(&tqpair->tcp_req_free_queue);
1072 	TAILQ_INIT(&tqpair->tcp_req_working_queue);
1073 
1074 	tqpair->host_hdgst_enable = true;
1075 	tqpair->host_ddgst_enable = true;
1076 
1077 	return 0;
1078 }
1079 
1080 static int
1081 nvmf_tcp_qpair_sock_init(struct spdk_nvmf_tcp_qpair *tqpair)
1082 {
1083 	int rc;
1084 
1085 	spdk_trace_record(TRACE_TCP_QP_SOCK_INIT, 0, 0, (uintptr_t)tqpair);
1086 
1087 	/* set low water mark */
1088 	rc = spdk_sock_set_recvlowat(tqpair->sock, sizeof(struct spdk_nvme_tcp_common_pdu_hdr));
1089 	if (rc != 0) {
1090 		SPDK_ERRLOG("spdk_sock_set_recvlowat() failed\n");
1091 		return rc;
1092 	}
1093 
1094 	return 0;
1095 }
1096 
1097 static void
1098 nvmf_tcp_handle_connect(struct spdk_nvmf_transport *transport,
1099 			struct spdk_nvmf_tcp_port *port,
1100 			struct spdk_sock *sock)
1101 {
1102 	struct spdk_nvmf_tcp_qpair *tqpair;
1103 	int rc;
1104 
1105 	SPDK_DEBUGLOG(nvmf_tcp, "New connection accepted on %s port %s\n",
1106 		      port->trid->traddr, port->trid->trsvcid);
1107 
1108 	tqpair = calloc(1, sizeof(struct spdk_nvmf_tcp_qpair));
1109 	if (tqpair == NULL) {
1110 		SPDK_ERRLOG("Could not allocate new connection.\n");
1111 		spdk_sock_close(&sock);
1112 		return;
1113 	}
1114 
1115 	tqpair->sock = sock;
1116 	tqpair->state_cntr[TCP_REQUEST_STATE_FREE] = 0;
1117 	tqpair->port = port;
1118 	tqpair->qpair.transport = transport;
1119 
1120 	rc = spdk_sock_getaddr(tqpair->sock, tqpair->target_addr,
1121 			       sizeof(tqpair->target_addr), &tqpair->target_port,
1122 			       tqpair->initiator_addr, sizeof(tqpair->initiator_addr),
1123 			       &tqpair->initiator_port);
1124 	if (rc < 0) {
1125 		SPDK_ERRLOG("spdk_sock_getaddr() failed of tqpair=%p\n", tqpair);
1126 		nvmf_tcp_qpair_destroy(tqpair);
1127 		return;
1128 	}
1129 
1130 	spdk_nvmf_tgt_new_qpair(transport->tgt, &tqpair->qpair);
1131 }
1132 
1133 static uint32_t
1134 nvmf_tcp_port_accept(struct spdk_nvmf_transport *transport, struct spdk_nvmf_tcp_port *port)
1135 {
1136 	struct spdk_sock *sock;
1137 	uint32_t count = 0;
1138 	int i;
1139 
1140 	for (i = 0; i < NVMF_TCP_MAX_ACCEPT_SOCK_ONE_TIME; i++) {
1141 		sock = spdk_sock_accept(port->listen_sock);
1142 		if (sock == NULL) {
1143 			break;
1144 		}
1145 		count++;
1146 		nvmf_tcp_handle_connect(transport, port, sock);
1147 	}
1148 
1149 	return count;
1150 }
1151 
1152 static int
1153 nvmf_tcp_accept(void *ctx)
1154 {
1155 	struct spdk_nvmf_transport *transport = ctx;
1156 	struct spdk_nvmf_tcp_transport *ttransport;
1157 	struct spdk_nvmf_tcp_port *port;
1158 	uint32_t count = 0;
1159 
1160 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
1161 
1162 	TAILQ_FOREACH(port, &ttransport->ports, link) {
1163 		count += nvmf_tcp_port_accept(transport, port);
1164 	}
1165 
1166 	return count > 0 ? SPDK_POLLER_BUSY : SPDK_POLLER_IDLE;
1167 }
1168 
1169 static void
1170 nvmf_tcp_discover(struct spdk_nvmf_transport *transport,
1171 		  struct spdk_nvme_transport_id *trid,
1172 		  struct spdk_nvmf_discovery_log_page_entry *entry)
1173 {
1174 	entry->trtype = SPDK_NVMF_TRTYPE_TCP;
1175 	entry->adrfam = trid->adrfam;
1176 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
1177 
1178 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
1179 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
1180 
1181 	entry->tsas.tcp.sectype = SPDK_NVME_TCP_SECURITY_NONE;
1182 }
1183 
1184 static struct spdk_nvmf_tcp_control_msg_list *
1185 nvmf_tcp_control_msg_list_create(uint16_t num_messages)
1186 {
1187 	struct spdk_nvmf_tcp_control_msg_list *list;
1188 	struct spdk_nvmf_tcp_control_msg *msg;
1189 	uint16_t i;
1190 
1191 	list = calloc(1, sizeof(*list));
1192 	if (!list) {
1193 		SPDK_ERRLOG("Failed to allocate memory for list structure\n");
1194 		return NULL;
1195 	}
1196 
1197 	list->msg_buf = spdk_zmalloc(num_messages * SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE,
1198 				     NVMF_DATA_BUFFER_ALIGNMENT, NULL, SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
1199 	if (!list->msg_buf) {
1200 		SPDK_ERRLOG("Failed to allocate memory for control message buffers\n");
1201 		free(list);
1202 		return NULL;
1203 	}
1204 
1205 	STAILQ_INIT(&list->free_msgs);
1206 
1207 	for (i = 0; i < num_messages; i++) {
1208 		msg = (struct spdk_nvmf_tcp_control_msg *)((char *)list->msg_buf + i *
1209 				SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE);
1210 		STAILQ_INSERT_TAIL(&list->free_msgs, msg, link);
1211 	}
1212 
1213 	return list;
1214 }
1215 
1216 static void
1217 nvmf_tcp_control_msg_list_free(struct spdk_nvmf_tcp_control_msg_list *list)
1218 {
1219 	if (!list) {
1220 		return;
1221 	}
1222 
1223 	spdk_free(list->msg_buf);
1224 	free(list);
1225 }
1226 
1227 static struct spdk_nvmf_transport_poll_group *
1228 nvmf_tcp_poll_group_create(struct spdk_nvmf_transport *transport)
1229 {
1230 	struct spdk_nvmf_tcp_transport	*ttransport;
1231 	struct spdk_nvmf_tcp_poll_group *tgroup;
1232 
1233 	tgroup = calloc(1, sizeof(*tgroup));
1234 	if (!tgroup) {
1235 		return NULL;
1236 	}
1237 
1238 	tgroup->sock_group = spdk_sock_group_create(&tgroup->group);
1239 	if (!tgroup->sock_group) {
1240 		goto cleanup;
1241 	}
1242 
1243 	TAILQ_INIT(&tgroup->qpairs);
1244 	TAILQ_INIT(&tgroup->await_req);
1245 
1246 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
1247 
1248 	if (transport->opts.in_capsule_data_size < SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE) {
1249 		SPDK_DEBUGLOG(nvmf_tcp, "ICD %u is less than min required for admin/fabric commands (%u). "
1250 			      "Creating control messages list\n", transport->opts.in_capsule_data_size,
1251 			      SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE);
1252 		tgroup->control_msg_list = nvmf_tcp_control_msg_list_create(ttransport->tcp_opts.control_msg_num);
1253 		if (!tgroup->control_msg_list) {
1254 			goto cleanup;
1255 		}
1256 	}
1257 
1258 	tgroup->accel_channel = spdk_accel_engine_get_io_channel();
1259 	if (spdk_unlikely(!tgroup->accel_channel)) {
1260 		SPDK_ERRLOG("Cannot create accel_channel for tgroup=%p\n", tgroup);
1261 		goto cleanup;
1262 	}
1263 
1264 	pthread_mutex_lock(&ttransport->lock);
1265 	TAILQ_INSERT_TAIL(&ttransport->poll_groups, tgroup, link);
1266 	if (ttransport->next_pg == NULL) {
1267 		ttransport->next_pg = tgroup;
1268 	}
1269 	pthread_mutex_unlock(&ttransport->lock);
1270 
1271 	return &tgroup->group;
1272 
1273 cleanup:
1274 	nvmf_tcp_poll_group_destroy(&tgroup->group);
1275 	return NULL;
1276 }
1277 
1278 static struct spdk_nvmf_transport_poll_group *
1279 nvmf_tcp_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
1280 {
1281 	struct spdk_nvmf_tcp_transport *ttransport;
1282 	struct spdk_nvmf_transport_poll_group *result;
1283 	struct spdk_nvmf_tcp_poll_group **pg;
1284 	struct spdk_nvmf_tcp_qpair *tqpair;
1285 	struct spdk_sock_group *group = NULL;
1286 	int rc;
1287 
1288 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
1289 	rc = spdk_sock_get_optimal_sock_group(tqpair->sock, &group);
1290 	if (!rc && group != NULL) {
1291 		return spdk_sock_group_get_ctx(group);
1292 	}
1293 
1294 	ttransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_tcp_transport, transport);
1295 
1296 	pthread_mutex_lock(&ttransport->lock);
1297 
1298 	if (TAILQ_EMPTY(&ttransport->poll_groups)) {
1299 		pthread_mutex_unlock(&ttransport->lock);
1300 		return NULL;
1301 	}
1302 
1303 	pg = &ttransport->next_pg;
1304 	assert(*pg != NULL);
1305 
1306 	result = &(*pg)->group;
1307 
1308 	*pg = TAILQ_NEXT(*pg, link);
1309 	if (*pg == NULL) {
1310 		*pg = TAILQ_FIRST(&ttransport->poll_groups);
1311 	}
1312 
1313 	pthread_mutex_unlock(&ttransport->lock);
1314 	return result;
1315 }
1316 
1317 static void
1318 nvmf_tcp_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
1319 {
1320 	struct spdk_nvmf_tcp_poll_group *tgroup, *next_tgroup;
1321 	struct spdk_nvmf_tcp_transport *ttransport;
1322 
1323 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
1324 	spdk_sock_group_close(&tgroup->sock_group);
1325 	if (tgroup->control_msg_list) {
1326 		nvmf_tcp_control_msg_list_free(tgroup->control_msg_list);
1327 	}
1328 
1329 	if (tgroup->accel_channel) {
1330 		spdk_put_io_channel(tgroup->accel_channel);
1331 	}
1332 
1333 	ttransport = SPDK_CONTAINEROF(tgroup->group.transport, struct spdk_nvmf_tcp_transport, transport);
1334 
1335 	pthread_mutex_lock(&ttransport->lock);
1336 	next_tgroup = TAILQ_NEXT(tgroup, link);
1337 	TAILQ_REMOVE(&ttransport->poll_groups, tgroup, link);
1338 	if (next_tgroup == NULL) {
1339 		next_tgroup = TAILQ_FIRST(&ttransport->poll_groups);
1340 	}
1341 	if (ttransport->next_pg == tgroup) {
1342 		ttransport->next_pg = next_tgroup;
1343 	}
1344 	pthread_mutex_unlock(&ttransport->lock);
1345 
1346 	free(tgroup);
1347 }
1348 
1349 static void
1350 nvmf_tcp_qpair_set_recv_state(struct spdk_nvmf_tcp_qpair *tqpair,
1351 			      enum nvme_tcp_pdu_recv_state state)
1352 {
1353 	if (tqpair->recv_state == state) {
1354 		SPDK_ERRLOG("The recv state of tqpair=%p is same with the state(%d) to be set\n",
1355 			    tqpair, state);
1356 		return;
1357 	}
1358 
1359 	if (tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_REQ) {
1360 		/* When leaving the await req state, move the qpair to the main list */
1361 		TAILQ_REMOVE(&tqpair->group->await_req, tqpair, link);
1362 		TAILQ_INSERT_TAIL(&tqpair->group->qpairs, tqpair, link);
1363 	}
1364 
1365 	SPDK_DEBUGLOG(nvmf_tcp, "tqpair(%p) recv state=%d\n", tqpair, state);
1366 	tqpair->recv_state = state;
1367 
1368 	spdk_trace_record(TRACE_TCP_QP_RCV_STATE_CHANGE, 0, 0, (uintptr_t)tqpair, tqpair->recv_state);
1369 
1370 	switch (state) {
1371 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH:
1372 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH:
1373 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:
1374 		break;
1375 	case NVME_TCP_PDU_RECV_STATE_AWAIT_REQ:
1376 		TAILQ_REMOVE(&tqpair->group->qpairs, tqpair, link);
1377 		TAILQ_INSERT_TAIL(&tqpair->group->await_req, tqpair, link);
1378 		break;
1379 	case NVME_TCP_PDU_RECV_STATE_ERROR:
1380 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY:
1381 		memset(tqpair->pdu_in_progress, 0, sizeof(*(tqpair->pdu_in_progress)));
1382 		break;
1383 	default:
1384 		SPDK_ERRLOG("The state(%d) is invalid\n", state);
1385 		abort();
1386 		break;
1387 	}
1388 }
1389 
1390 static int
1391 nvmf_tcp_qpair_handle_timeout(void *ctx)
1392 {
1393 	struct spdk_nvmf_tcp_qpair *tqpair = ctx;
1394 
1395 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_ERROR);
1396 
1397 	SPDK_ERRLOG("No pdu coming for tqpair=%p within %d seconds\n", tqpair,
1398 		    SPDK_NVME_TCP_QPAIR_EXIT_TIMEOUT);
1399 
1400 	nvmf_tcp_qpair_disconnect(tqpair);
1401 	return SPDK_POLLER_BUSY;
1402 }
1403 
1404 static void
1405 nvmf_tcp_send_c2h_term_req_complete(void *cb_arg)
1406 {
1407 	struct spdk_nvmf_tcp_qpair *tqpair = (struct spdk_nvmf_tcp_qpair *)cb_arg;
1408 
1409 	if (!tqpair->timeout_poller) {
1410 		tqpair->timeout_poller = SPDK_POLLER_REGISTER(nvmf_tcp_qpair_handle_timeout, tqpair,
1411 					 SPDK_NVME_TCP_QPAIR_EXIT_TIMEOUT * 1000000);
1412 	}
1413 }
1414 
1415 static void
1416 nvmf_tcp_send_c2h_term_req(struct spdk_nvmf_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu,
1417 			   enum spdk_nvme_tcp_term_req_fes fes, uint32_t error_offset)
1418 {
1419 	struct nvme_tcp_pdu *rsp_pdu;
1420 	struct spdk_nvme_tcp_term_req_hdr *c2h_term_req;
1421 	uint32_t c2h_term_req_hdr_len = sizeof(*c2h_term_req);
1422 	uint32_t copy_len;
1423 
1424 	rsp_pdu = tqpair->mgmt_pdu;
1425 
1426 	c2h_term_req = &rsp_pdu->hdr.term_req;
1427 	c2h_term_req->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ;
1428 	c2h_term_req->common.hlen = c2h_term_req_hdr_len;
1429 
1430 	if ((fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
1431 	    (fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
1432 		DSET32(&c2h_term_req->fei, error_offset);
1433 	}
1434 
1435 	copy_len = spdk_min(pdu->hdr.common.hlen, SPDK_NVME_TCP_TERM_REQ_ERROR_DATA_MAX_SIZE);
1436 
1437 	/* Copy the error info into the buffer */
1438 	memcpy((uint8_t *)rsp_pdu->hdr.raw + c2h_term_req_hdr_len, pdu->hdr.raw, copy_len);
1439 	nvme_tcp_pdu_set_data(rsp_pdu, (uint8_t *)rsp_pdu->hdr.raw + c2h_term_req_hdr_len, copy_len);
1440 
1441 	/* Contain the header of the wrong received pdu */
1442 	c2h_term_req->common.plen = c2h_term_req->common.hlen + copy_len;
1443 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1444 	nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, nvmf_tcp_send_c2h_term_req_complete, tqpair);
1445 }
1446 
1447 static void
1448 nvmf_tcp_capsule_cmd_hdr_handle(struct spdk_nvmf_tcp_transport *ttransport,
1449 				struct spdk_nvmf_tcp_qpair *tqpair,
1450 				struct nvme_tcp_pdu *pdu)
1451 {
1452 	struct spdk_nvmf_tcp_req *tcp_req;
1453 
1454 	assert(pdu->psh_valid_bytes == pdu->psh_len);
1455 	assert(pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD);
1456 
1457 	tcp_req = nvmf_tcp_req_get(tqpair);
1458 	if (!tcp_req) {
1459 		/* Directly return and make the allocation retry again.  This can happen if we're
1460 		 * using asynchronous writes to send the response to the host or when releasing
1461 		 * zero-copy buffers after a response has been sent.  In both cases, the host might
1462 		 * receive the response before we've finished processing the request and is free to
1463 		 * send another one.
1464 		 */
1465 		if (tqpair->state_cntr[TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST] > 0 ||
1466 		    tqpair->state_cntr[TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE] > 0) {
1467 			return;
1468 		}
1469 
1470 		/* The host sent more commands than the maximum queue depth. */
1471 		SPDK_ERRLOG("Cannot allocate tcp_req on tqpair=%p\n", tqpair);
1472 		nvmf_tcp_qpair_disconnect(tqpair);
1473 		return;
1474 	}
1475 
1476 	pdu->req = tcp_req;
1477 	assert(tcp_req->state == TCP_REQUEST_STATE_NEW);
1478 	nvmf_tcp_req_process(ttransport, tcp_req);
1479 }
1480 
1481 static void
1482 nvmf_tcp_capsule_cmd_payload_handle(struct spdk_nvmf_tcp_transport *ttransport,
1483 				    struct spdk_nvmf_tcp_qpair *tqpair,
1484 				    struct nvme_tcp_pdu *pdu)
1485 {
1486 	struct spdk_nvmf_tcp_req *tcp_req;
1487 	struct spdk_nvme_tcp_cmd *capsule_cmd;
1488 	uint32_t error_offset = 0;
1489 	enum spdk_nvme_tcp_term_req_fes fes;
1490 	struct spdk_nvme_cpl *rsp;
1491 
1492 	capsule_cmd = &pdu->hdr.capsule_cmd;
1493 	tcp_req = pdu->req;
1494 	assert(tcp_req != NULL);
1495 
1496 	/* Zero-copy requests don't support ICD */
1497 	assert(!spdk_nvmf_request_using_zcopy(&tcp_req->req));
1498 
1499 	if (capsule_cmd->common.pdo > SPDK_NVME_TCP_PDU_PDO_MAX_OFFSET) {
1500 		SPDK_ERRLOG("Expected ICReq capsule_cmd pdu offset <= %d, got %c\n",
1501 			    SPDK_NVME_TCP_PDU_PDO_MAX_OFFSET, capsule_cmd->common.pdo);
1502 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1503 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdo);
1504 		goto err;
1505 	}
1506 
1507 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1508 
1509 	rsp = &tcp_req->req.rsp->nvme_cpl;
1510 	if (spdk_unlikely(rsp->status.sc == SPDK_NVME_SC_COMMAND_TRANSIENT_TRANSPORT_ERROR)) {
1511 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
1512 	} else {
1513 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1514 	}
1515 
1516 	nvmf_tcp_req_process(ttransport, tcp_req);
1517 
1518 	return;
1519 err:
1520 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1521 }
1522 
1523 static int
1524 nvmf_tcp_find_req_in_state(struct spdk_nvmf_tcp_qpair *tqpair,
1525 			   enum spdk_nvmf_tcp_req_state state,
1526 			   uint16_t cid, uint16_t tag,
1527 			   struct spdk_nvmf_tcp_req **req)
1528 {
1529 	struct spdk_nvmf_tcp_req *tcp_req = NULL;
1530 
1531 	TAILQ_FOREACH(tcp_req, &tqpair->tcp_req_working_queue, state_link) {
1532 		if (tcp_req->state != state) {
1533 			continue;
1534 		}
1535 
1536 		if (tcp_req->req.cmd->nvme_cmd.cid != cid) {
1537 			continue;
1538 		}
1539 
1540 		if (tcp_req->ttag == tag) {
1541 			*req = tcp_req;
1542 			return 0;
1543 		}
1544 
1545 		*req = NULL;
1546 		return -1;
1547 	}
1548 
1549 	/* Didn't find it, but not an error */
1550 	*req = NULL;
1551 	return 0;
1552 }
1553 
1554 static void
1555 nvmf_tcp_h2c_data_hdr_handle(struct spdk_nvmf_tcp_transport *ttransport,
1556 			     struct spdk_nvmf_tcp_qpair *tqpair,
1557 			     struct nvme_tcp_pdu *pdu)
1558 {
1559 	struct spdk_nvmf_tcp_req *tcp_req;
1560 	uint32_t error_offset = 0;
1561 	enum spdk_nvme_tcp_term_req_fes fes = 0;
1562 	struct spdk_nvme_tcp_h2c_data_hdr *h2c_data;
1563 	int rc;
1564 
1565 	h2c_data = &pdu->hdr.h2c_data;
1566 
1567 	SPDK_DEBUGLOG(nvmf_tcp, "tqpair=%p, r2t_info: datao=%u, datal=%u, cccid=%u, ttag=%u\n",
1568 		      tqpair, h2c_data->datao, h2c_data->datal, h2c_data->cccid, h2c_data->ttag);
1569 
1570 	rc = nvmf_tcp_find_req_in_state(tqpair, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
1571 					h2c_data->cccid, h2c_data->ttag, &tcp_req);
1572 	if (rc == 0 && tcp_req == NULL) {
1573 		rc = nvmf_tcp_find_req_in_state(tqpair, TCP_REQUEST_STATE_AWAITING_R2T_ACK, h2c_data->cccid,
1574 						h2c_data->ttag, &tcp_req);
1575 	}
1576 
1577 	if (!tcp_req) {
1578 		SPDK_DEBUGLOG(nvmf_tcp, "tcp_req is not found for tqpair=%p\n", tqpair);
1579 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER;
1580 		if (rc == 0) {
1581 			error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, cccid);
1582 		} else {
1583 			error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, ttag);
1584 		}
1585 		goto err;
1586 	}
1587 
1588 	if (tcp_req->h2c_offset != h2c_data->datao) {
1589 		SPDK_DEBUGLOG(nvmf_tcp,
1590 			      "tcp_req(%p), tqpair=%p, expected data offset %u, but data offset is %u\n",
1591 			      tcp_req, tqpair, tcp_req->h2c_offset, h2c_data->datao);
1592 		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
1593 		goto err;
1594 	}
1595 
1596 	if ((h2c_data->datao + h2c_data->datal) > tcp_req->req.length) {
1597 		SPDK_DEBUGLOG(nvmf_tcp,
1598 			      "tcp_req(%p), tqpair=%p,  (datao=%u + datal=%u) exceeds requested length=%u\n",
1599 			      tcp_req, tqpair, h2c_data->datao, h2c_data->datal, tcp_req->req.length);
1600 		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
1601 		goto err;
1602 	}
1603 
1604 	pdu->req = tcp_req;
1605 
1606 	if (spdk_unlikely(tcp_req->req.dif_enabled)) {
1607 		pdu->dif_ctx = &tcp_req->req.dif.dif_ctx;
1608 	}
1609 
1610 	nvme_tcp_pdu_set_data_buf(pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
1611 				  h2c_data->datao, h2c_data->datal);
1612 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1613 	return;
1614 
1615 err:
1616 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1617 }
1618 
1619 static void
1620 nvmf_tcp_send_capsule_resp_pdu(struct spdk_nvmf_tcp_req *tcp_req,
1621 			       struct spdk_nvmf_tcp_qpair *tqpair)
1622 {
1623 	struct nvme_tcp_pdu *rsp_pdu;
1624 	struct spdk_nvme_tcp_rsp *capsule_resp;
1625 
1626 	SPDK_DEBUGLOG(nvmf_tcp, "enter, tqpair=%p\n", tqpair);
1627 
1628 	rsp_pdu = nvmf_tcp_req_pdu_init(tcp_req);
1629 	assert(rsp_pdu != NULL);
1630 
1631 	capsule_resp = &rsp_pdu->hdr.capsule_resp;
1632 	capsule_resp->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_CAPSULE_RESP;
1633 	capsule_resp->common.plen = capsule_resp->common.hlen = sizeof(*capsule_resp);
1634 	capsule_resp->rccqe = tcp_req->req.rsp->nvme_cpl;
1635 	if (tqpair->host_hdgst_enable) {
1636 		capsule_resp->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
1637 		capsule_resp->common.plen += SPDK_NVME_TCP_DIGEST_LEN;
1638 	}
1639 
1640 	nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, nvmf_tcp_request_free, tcp_req);
1641 }
1642 
1643 static void
1644 nvmf_tcp_pdu_c2h_data_complete(void *cb_arg)
1645 {
1646 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
1647 	struct spdk_nvmf_tcp_qpair *tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair,
1648 					     struct spdk_nvmf_tcp_qpair, qpair);
1649 
1650 	assert(tqpair != NULL);
1651 
1652 	if (spdk_unlikely(tcp_req->pdu->rw_offset < tcp_req->req.length)) {
1653 		SPDK_DEBUGLOG(nvmf_tcp, "sending another C2H part, offset %u length %u\n", tcp_req->pdu->rw_offset,
1654 			      tcp_req->req.length);
1655 		_nvmf_tcp_send_c2h_data(tqpair, tcp_req);
1656 		return;
1657 	}
1658 
1659 	if (tcp_req->pdu->hdr.c2h_data.common.flags & SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS) {
1660 		nvmf_tcp_request_free(tcp_req);
1661 	} else {
1662 		nvmf_tcp_req_pdu_fini(tcp_req);
1663 		nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
1664 	}
1665 }
1666 
1667 static void
1668 nvmf_tcp_r2t_complete(void *cb_arg)
1669 {
1670 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
1671 	struct spdk_nvmf_tcp_transport *ttransport;
1672 
1673 	nvmf_tcp_req_pdu_fini(tcp_req);
1674 
1675 	ttransport = SPDK_CONTAINEROF(tcp_req->req.qpair->transport,
1676 				      struct spdk_nvmf_tcp_transport, transport);
1677 
1678 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
1679 
1680 	if (tcp_req->h2c_offset == tcp_req->req.length) {
1681 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1682 		nvmf_tcp_req_process(ttransport, tcp_req);
1683 	}
1684 }
1685 
1686 static void
1687 nvmf_tcp_send_r2t_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
1688 		      struct spdk_nvmf_tcp_req *tcp_req)
1689 {
1690 	struct nvme_tcp_pdu *rsp_pdu;
1691 	struct spdk_nvme_tcp_r2t_hdr *r2t;
1692 
1693 	rsp_pdu = nvmf_tcp_req_pdu_init(tcp_req);
1694 	assert(rsp_pdu != NULL);
1695 
1696 	r2t = &rsp_pdu->hdr.r2t;
1697 	r2t->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_R2T;
1698 	r2t->common.plen = r2t->common.hlen = sizeof(*r2t);
1699 
1700 	if (tqpair->host_hdgst_enable) {
1701 		r2t->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
1702 		r2t->common.plen += SPDK_NVME_TCP_DIGEST_LEN;
1703 	}
1704 
1705 	r2t->cccid = tcp_req->req.cmd->nvme_cmd.cid;
1706 	r2t->ttag = tcp_req->ttag;
1707 	r2t->r2to = tcp_req->h2c_offset;
1708 	r2t->r2tl = tcp_req->req.length;
1709 
1710 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_R2T_ACK);
1711 
1712 	SPDK_DEBUGLOG(nvmf_tcp,
1713 		      "tcp_req(%p) on tqpair(%p), r2t_info: cccid=%u, ttag=%u, r2to=%u, r2tl=%u\n",
1714 		      tcp_req, tqpair, r2t->cccid, r2t->ttag, r2t->r2to, r2t->r2tl);
1715 	nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, nvmf_tcp_r2t_complete, tcp_req);
1716 }
1717 
1718 static void
1719 nvmf_tcp_h2c_data_payload_handle(struct spdk_nvmf_tcp_transport *ttransport,
1720 				 struct spdk_nvmf_tcp_qpair *tqpair,
1721 				 struct nvme_tcp_pdu *pdu)
1722 {
1723 	struct spdk_nvmf_tcp_req *tcp_req;
1724 	struct spdk_nvme_cpl *rsp;
1725 
1726 	tcp_req = pdu->req;
1727 	assert(tcp_req != NULL);
1728 
1729 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
1730 
1731 	tcp_req->h2c_offset += pdu->data_len;
1732 
1733 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1734 
1735 	/* Wait for all of the data to arrive AND for the initial R2T PDU send to be
1736 	 * acknowledged before moving on. */
1737 	if (tcp_req->h2c_offset == tcp_req->req.length &&
1738 	    tcp_req->state == TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER) {
1739 		/* After receiving all the h2c data, we need to check whether there is
1740 		 * transient transport error */
1741 		rsp = &tcp_req->req.rsp->nvme_cpl;
1742 		if (spdk_unlikely(rsp->status.sc == SPDK_NVME_SC_COMMAND_TRANSIENT_TRANSPORT_ERROR)) {
1743 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
1744 		} else {
1745 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1746 		}
1747 		nvmf_tcp_req_process(ttransport, tcp_req);
1748 	}
1749 }
1750 
1751 static void
1752 nvmf_tcp_h2c_term_req_dump(struct spdk_nvme_tcp_term_req_hdr *h2c_term_req)
1753 {
1754 	SPDK_ERRLOG("Error info of pdu(%p): %s\n", h2c_term_req,
1755 		    spdk_nvmf_tcp_term_req_fes_str[h2c_term_req->fes]);
1756 	if ((h2c_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
1757 	    (h2c_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
1758 		SPDK_DEBUGLOG(nvmf_tcp, "The offset from the start of the PDU header is %u\n",
1759 			      DGET32(h2c_term_req->fei));
1760 	}
1761 }
1762 
1763 static void
1764 nvmf_tcp_h2c_term_req_hdr_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1765 				 struct nvme_tcp_pdu *pdu)
1766 {
1767 	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req = &pdu->hdr.term_req;
1768 	uint32_t error_offset = 0;
1769 	enum spdk_nvme_tcp_term_req_fes fes;
1770 
1771 	if (h2c_term_req->fes > SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER) {
1772 		SPDK_ERRLOG("Fatal Error Status(FES) is unknown for h2c_term_req pdu=%p\n", pdu);
1773 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1774 		error_offset = offsetof(struct spdk_nvme_tcp_term_req_hdr, fes);
1775 		goto end;
1776 	}
1777 
1778 	/* set the data buffer */
1779 	nvme_tcp_pdu_set_data(pdu, (uint8_t *)pdu->hdr.raw + h2c_term_req->common.hlen,
1780 			      h2c_term_req->common.plen - h2c_term_req->common.hlen);
1781 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1782 	return;
1783 end:
1784 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1785 }
1786 
1787 static void
1788 nvmf_tcp_h2c_term_req_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1789 				     struct nvme_tcp_pdu *pdu)
1790 {
1791 	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req = &pdu->hdr.term_req;
1792 
1793 	nvmf_tcp_h2c_term_req_dump(h2c_term_req);
1794 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1795 }
1796 
1797 static void
1798 _nvmf_tcp_pdu_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1799 			     struct spdk_nvmf_tcp_transport *ttransport)
1800 {
1801 	struct nvme_tcp_pdu *pdu = tqpair->pdu_in_progress;
1802 
1803 	switch (pdu->hdr.common.pdu_type) {
1804 	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
1805 		nvmf_tcp_capsule_cmd_payload_handle(ttransport, tqpair, pdu);
1806 		break;
1807 	case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
1808 		nvmf_tcp_h2c_data_payload_handle(ttransport, tqpair, pdu);
1809 		break;
1810 
1811 	case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
1812 		nvmf_tcp_h2c_term_req_payload_handle(tqpair, pdu);
1813 		break;
1814 
1815 	default:
1816 		/* The code should not go to here */
1817 		SPDK_ERRLOG("The code should not go to here\n");
1818 		break;
1819 	}
1820 }
1821 
1822 static void
1823 nvmf_tcp_pdu_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1824 			    struct spdk_nvmf_tcp_transport *ttransport)
1825 {
1826 	int rc = 0;
1827 	struct nvme_tcp_pdu *pdu;
1828 	uint32_t crc32c;
1829 	struct spdk_nvmf_tcp_req *tcp_req;
1830 	struct spdk_nvme_cpl *rsp;
1831 
1832 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1833 	pdu = tqpair->pdu_in_progress;
1834 
1835 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
1836 	/* check data digest if need */
1837 	if (pdu->ddgst_enable) {
1838 		crc32c = nvme_tcp_pdu_calc_data_digest(pdu);
1839 		rc = MATCH_DIGEST_WORD(pdu->data_digest, crc32c);
1840 		if (rc == 0) {
1841 			SPDK_ERRLOG("Data digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
1842 			tcp_req = pdu->req;
1843 			assert(tcp_req != NULL);
1844 			rsp = &tcp_req->req.rsp->nvme_cpl;
1845 			rsp->status.sc = SPDK_NVME_SC_COMMAND_TRANSIENT_TRANSPORT_ERROR;
1846 		}
1847 	}
1848 
1849 	_nvmf_tcp_pdu_payload_handle(tqpair, ttransport);
1850 }
1851 
1852 static void
1853 nvmf_tcp_send_icresp_complete(void *cb_arg)
1854 {
1855 	struct spdk_nvmf_tcp_qpair *tqpair = cb_arg;
1856 
1857 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_RUNNING);
1858 }
1859 
1860 static void
1861 nvmf_tcp_icreq_handle(struct spdk_nvmf_tcp_transport *ttransport,
1862 		      struct spdk_nvmf_tcp_qpair *tqpair,
1863 		      struct nvme_tcp_pdu *pdu)
1864 {
1865 	struct spdk_nvme_tcp_ic_req *ic_req = &pdu->hdr.ic_req;
1866 	struct nvme_tcp_pdu *rsp_pdu;
1867 	struct spdk_nvme_tcp_ic_resp *ic_resp;
1868 	uint32_t error_offset = 0;
1869 	enum spdk_nvme_tcp_term_req_fes fes;
1870 
1871 	/* Only PFV 0 is defined currently */
1872 	if (ic_req->pfv != 0) {
1873 		SPDK_ERRLOG("Expected ICReq PFV %u, got %u\n", 0u, ic_req->pfv);
1874 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1875 		error_offset = offsetof(struct spdk_nvme_tcp_ic_req, pfv);
1876 		goto end;
1877 	}
1878 
1879 	/* MAXR2T is 0's based */
1880 	SPDK_DEBUGLOG(nvmf_tcp, "maxr2t =%u\n", (ic_req->maxr2t + 1u));
1881 
1882 	tqpair->host_hdgst_enable = ic_req->dgst.bits.hdgst_enable ? true : false;
1883 	if (!tqpair->host_hdgst_enable) {
1884 		tqpair->recv_buf_size -= SPDK_NVME_TCP_DIGEST_LEN * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
1885 	}
1886 
1887 	tqpair->host_ddgst_enable = ic_req->dgst.bits.ddgst_enable ? true : false;
1888 	if (!tqpair->host_ddgst_enable) {
1889 		tqpair->recv_buf_size -= SPDK_NVME_TCP_DIGEST_LEN * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
1890 	}
1891 
1892 	tqpair->recv_buf_size = spdk_max(tqpair->recv_buf_size, MIN_SOCK_PIPE_SIZE);
1893 	/* Now that we know whether digests are enabled, properly size the receive buffer */
1894 	if (spdk_sock_set_recvbuf(tqpair->sock, tqpair->recv_buf_size) < 0) {
1895 		SPDK_WARNLOG("Unable to allocate enough memory for receive buffer on tqpair=%p with size=%d\n",
1896 			     tqpair,
1897 			     tqpair->recv_buf_size);
1898 		/* Not fatal. */
1899 	}
1900 
1901 	tqpair->cpda = spdk_min(ic_req->hpda, SPDK_NVME_TCP_CPDA_MAX);
1902 	SPDK_DEBUGLOG(nvmf_tcp, "cpda of tqpair=(%p) is : %u\n", tqpair, tqpair->cpda);
1903 
1904 	rsp_pdu = tqpair->mgmt_pdu;
1905 
1906 	ic_resp = &rsp_pdu->hdr.ic_resp;
1907 	ic_resp->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_IC_RESP;
1908 	ic_resp->common.hlen = ic_resp->common.plen =  sizeof(*ic_resp);
1909 	ic_resp->pfv = 0;
1910 	ic_resp->cpda = tqpair->cpda;
1911 	ic_resp->maxh2cdata = ttransport->transport.opts.max_io_size;
1912 	ic_resp->dgst.bits.hdgst_enable = tqpair->host_hdgst_enable ? 1 : 0;
1913 	ic_resp->dgst.bits.ddgst_enable = tqpair->host_ddgst_enable ? 1 : 0;
1914 
1915 	SPDK_DEBUGLOG(nvmf_tcp, "host_hdgst_enable: %u\n", tqpair->host_hdgst_enable);
1916 	SPDK_DEBUGLOG(nvmf_tcp, "host_ddgst_enable: %u\n", tqpair->host_ddgst_enable);
1917 
1918 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_INITIALIZING);
1919 	nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, nvmf_tcp_send_icresp_complete, tqpair);
1920 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1921 	return;
1922 end:
1923 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1924 }
1925 
1926 static void
1927 nvmf_tcp_pdu_psh_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1928 			struct spdk_nvmf_tcp_transport *ttransport)
1929 {
1930 	struct nvme_tcp_pdu *pdu;
1931 	int rc;
1932 	uint32_t crc32c, error_offset = 0;
1933 	enum spdk_nvme_tcp_term_req_fes fes;
1934 
1935 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
1936 	pdu = tqpair->pdu_in_progress;
1937 
1938 	SPDK_DEBUGLOG(nvmf_tcp, "pdu type of tqpair(%p) is %d\n", tqpair,
1939 		      pdu->hdr.common.pdu_type);
1940 	/* check header digest if needed */
1941 	if (pdu->has_hdgst) {
1942 		SPDK_DEBUGLOG(nvmf_tcp, "Compare the header of pdu=%p on tqpair=%p\n", pdu, tqpair);
1943 		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
1944 		rc = MATCH_DIGEST_WORD((uint8_t *)pdu->hdr.raw + pdu->hdr.common.hlen, crc32c);
1945 		if (rc == 0) {
1946 			SPDK_ERRLOG("Header digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
1947 			fes = SPDK_NVME_TCP_TERM_REQ_FES_HDGST_ERROR;
1948 			nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1949 			return;
1950 
1951 		}
1952 	}
1953 
1954 	switch (pdu->hdr.common.pdu_type) {
1955 	case SPDK_NVME_TCP_PDU_TYPE_IC_REQ:
1956 		nvmf_tcp_icreq_handle(ttransport, tqpair, pdu);
1957 		break;
1958 	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
1959 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_REQ);
1960 		break;
1961 	case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
1962 		nvmf_tcp_h2c_data_hdr_handle(ttransport, tqpair, pdu);
1963 		break;
1964 
1965 	case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
1966 		nvmf_tcp_h2c_term_req_hdr_handle(tqpair, pdu);
1967 		break;
1968 
1969 	default:
1970 		SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", tqpair->pdu_in_progress->hdr.common.pdu_type);
1971 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1972 		error_offset = 1;
1973 		nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1974 		break;
1975 	}
1976 }
1977 
1978 static void
1979 nvmf_tcp_pdu_ch_handle(struct spdk_nvmf_tcp_qpair *tqpair)
1980 {
1981 	struct nvme_tcp_pdu *pdu;
1982 	uint32_t error_offset = 0;
1983 	enum spdk_nvme_tcp_term_req_fes fes;
1984 	uint8_t expected_hlen, pdo;
1985 	bool plen_error = false, pdo_error = false;
1986 
1987 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
1988 	pdu = tqpair->pdu_in_progress;
1989 
1990 	if (pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_REQ) {
1991 		if (tqpair->state != NVME_TCP_QPAIR_STATE_INVALID) {
1992 			SPDK_ERRLOG("Already received ICreq PDU, and reject this pdu=%p\n", pdu);
1993 			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
1994 			goto err;
1995 		}
1996 		expected_hlen = sizeof(struct spdk_nvme_tcp_ic_req);
1997 		if (pdu->hdr.common.plen != expected_hlen) {
1998 			plen_error = true;
1999 		}
2000 	} else {
2001 		if (tqpair->state != NVME_TCP_QPAIR_STATE_RUNNING) {
2002 			SPDK_ERRLOG("The TCP/IP connection is not negotiated\n");
2003 			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
2004 			goto err;
2005 		}
2006 
2007 		switch (pdu->hdr.common.pdu_type) {
2008 		case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
2009 			expected_hlen = sizeof(struct spdk_nvme_tcp_cmd);
2010 			pdo = pdu->hdr.common.pdo;
2011 			if ((tqpair->cpda != 0) && (pdo % ((tqpair->cpda + 1) << 2) != 0)) {
2012 				pdo_error = true;
2013 				break;
2014 			}
2015 
2016 			if (pdu->hdr.common.plen < expected_hlen) {
2017 				plen_error = true;
2018 			}
2019 			break;
2020 		case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
2021 			expected_hlen = sizeof(struct spdk_nvme_tcp_h2c_data_hdr);
2022 			pdo = pdu->hdr.common.pdo;
2023 			if ((tqpair->cpda != 0) && (pdo % ((tqpair->cpda + 1) << 2) != 0)) {
2024 				pdo_error = true;
2025 				break;
2026 			}
2027 			if (pdu->hdr.common.plen < expected_hlen) {
2028 				plen_error = true;
2029 			}
2030 			break;
2031 
2032 		case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
2033 			expected_hlen = sizeof(struct spdk_nvme_tcp_term_req_hdr);
2034 			if ((pdu->hdr.common.plen <= expected_hlen) ||
2035 			    (pdu->hdr.common.plen > SPDK_NVME_TCP_TERM_REQ_PDU_MAX_SIZE)) {
2036 				plen_error = true;
2037 			}
2038 			break;
2039 
2040 		default:
2041 			SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", pdu->hdr.common.pdu_type);
2042 			fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2043 			error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdu_type);
2044 			goto err;
2045 		}
2046 	}
2047 
2048 	if (pdu->hdr.common.hlen != expected_hlen) {
2049 		SPDK_ERRLOG("PDU type=0x%02x, Expected ICReq header length %u, got %u on tqpair=%p\n",
2050 			    pdu->hdr.common.pdu_type,
2051 			    expected_hlen, pdu->hdr.common.hlen, tqpair);
2052 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2053 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, hlen);
2054 		goto err;
2055 	} else if (pdo_error) {
2056 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2057 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdo);
2058 	} else if (plen_error) {
2059 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2060 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, plen);
2061 		goto err;
2062 	} else {
2063 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
2064 		nvme_tcp_pdu_calc_psh_len(tqpair->pdu_in_progress, tqpair->host_hdgst_enable);
2065 		return;
2066 	}
2067 err:
2068 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
2069 }
2070 
2071 static int
2072 nvmf_tcp_pdu_payload_insert_dif(struct nvme_tcp_pdu *pdu, uint32_t read_offset,
2073 				int read_len)
2074 {
2075 	int rc;
2076 
2077 	rc = spdk_dif_generate_stream(pdu->data_iov, pdu->data_iovcnt,
2078 				      read_offset, read_len, pdu->dif_ctx);
2079 	if (rc != 0) {
2080 		SPDK_ERRLOG("DIF generate failed\n");
2081 	}
2082 
2083 	return rc;
2084 }
2085 
2086 static int
2087 nvmf_tcp_sock_process(struct spdk_nvmf_tcp_qpair *tqpair)
2088 {
2089 	int rc = 0;
2090 	struct nvme_tcp_pdu *pdu;
2091 	enum nvme_tcp_pdu_recv_state prev_state;
2092 	uint32_t data_len;
2093 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport,
2094 			struct spdk_nvmf_tcp_transport, transport);
2095 
2096 	/* The loop here is to allow for several back-to-back state changes. */
2097 	do {
2098 		prev_state = tqpair->recv_state;
2099 		SPDK_DEBUGLOG(nvmf_tcp, "tqpair(%p) recv pdu entering state %d\n", tqpair, prev_state);
2100 
2101 		pdu = tqpair->pdu_in_progress;
2102 		switch (tqpair->recv_state) {
2103 		/* Wait for the common header  */
2104 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY:
2105 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH:
2106 			if (spdk_unlikely(tqpair->state == NVME_TCP_QPAIR_STATE_INITIALIZING)) {
2107 				return rc;
2108 			}
2109 
2110 			rc = nvme_tcp_read_data(tqpair->sock,
2111 						sizeof(struct spdk_nvme_tcp_common_pdu_hdr) - pdu->ch_valid_bytes,
2112 						(void *)&pdu->hdr.common + pdu->ch_valid_bytes);
2113 			if (rc < 0) {
2114 				SPDK_DEBUGLOG(nvmf_tcp, "will disconnect tqpair=%p\n", tqpair);
2115 				return NVME_TCP_PDU_FATAL;
2116 			} else if (rc > 0) {
2117 				pdu->ch_valid_bytes += rc;
2118 				spdk_trace_record(TRACE_TCP_READ_FROM_SOCKET_DONE, 0, rc, 0, tqpair);
2119 				if (spdk_likely(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY)) {
2120 					nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
2121 				}
2122 			}
2123 
2124 			if (pdu->ch_valid_bytes < sizeof(struct spdk_nvme_tcp_common_pdu_hdr)) {
2125 				return NVME_TCP_PDU_IN_PROGRESS;
2126 			}
2127 
2128 			/* The command header of this PDU has now been read from the socket. */
2129 			nvmf_tcp_pdu_ch_handle(tqpair);
2130 			break;
2131 		/* Wait for the pdu specific header  */
2132 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH:
2133 			rc = nvme_tcp_read_data(tqpair->sock,
2134 						pdu->psh_len - pdu->psh_valid_bytes,
2135 						(void *)&pdu->hdr.raw + sizeof(struct spdk_nvme_tcp_common_pdu_hdr) + pdu->psh_valid_bytes);
2136 			if (rc < 0) {
2137 				return NVME_TCP_PDU_FATAL;
2138 			} else if (rc > 0) {
2139 				spdk_trace_record(TRACE_TCP_READ_FROM_SOCKET_DONE, 0, rc, 0, tqpair);
2140 				pdu->psh_valid_bytes += rc;
2141 			}
2142 
2143 			if (pdu->psh_valid_bytes < pdu->psh_len) {
2144 				return NVME_TCP_PDU_IN_PROGRESS;
2145 			}
2146 
2147 			/* All header(ch, psh, head digist) of this PDU has now been read from the socket. */
2148 			nvmf_tcp_pdu_psh_handle(tqpair, ttransport);
2149 			break;
2150 		/* Wait for the req slot */
2151 		case NVME_TCP_PDU_RECV_STATE_AWAIT_REQ:
2152 			nvmf_tcp_capsule_cmd_hdr_handle(ttransport, tqpair, pdu);
2153 			break;
2154 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:
2155 			/* check whether the data is valid, if not we just return */
2156 			if (!pdu->data_len) {
2157 				return NVME_TCP_PDU_IN_PROGRESS;
2158 			}
2159 
2160 			data_len = pdu->data_len;
2161 			/* data digest */
2162 			if (spdk_unlikely((pdu->hdr.common.pdu_type != SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ) &&
2163 					  tqpair->host_ddgst_enable)) {
2164 				data_len += SPDK_NVME_TCP_DIGEST_LEN;
2165 				pdu->ddgst_enable = true;
2166 			}
2167 
2168 			rc = nvme_tcp_read_payload_data(tqpair->sock, pdu);
2169 			if (rc < 0) {
2170 				return NVME_TCP_PDU_FATAL;
2171 			}
2172 			pdu->rw_offset += rc;
2173 
2174 			if (spdk_unlikely(pdu->dif_ctx != NULL)) {
2175 				rc = nvmf_tcp_pdu_payload_insert_dif(pdu, pdu->rw_offset - rc, rc);
2176 				if (rc != 0) {
2177 					return NVME_TCP_PDU_FATAL;
2178 				}
2179 			}
2180 
2181 			if (pdu->rw_offset < data_len) {
2182 				return NVME_TCP_PDU_IN_PROGRESS;
2183 			}
2184 
2185 			/* All of this PDU has now been read from the socket. */
2186 			nvmf_tcp_pdu_payload_handle(tqpair, ttransport);
2187 			break;
2188 		case NVME_TCP_PDU_RECV_STATE_ERROR:
2189 			if (!spdk_sock_is_connected(tqpair->sock)) {
2190 				return NVME_TCP_PDU_FATAL;
2191 			}
2192 			break;
2193 		default:
2194 			assert(0);
2195 			SPDK_ERRLOG("code should not come to here");
2196 			break;
2197 		}
2198 	} while (tqpair->recv_state != prev_state);
2199 
2200 	return rc;
2201 }
2202 
2203 static inline void *
2204 nvmf_tcp_control_msg_get(struct spdk_nvmf_tcp_control_msg_list *list)
2205 {
2206 	struct spdk_nvmf_tcp_control_msg *msg;
2207 
2208 	assert(list);
2209 
2210 	msg = STAILQ_FIRST(&list->free_msgs);
2211 	if (!msg) {
2212 		SPDK_DEBUGLOG(nvmf_tcp, "Out of control messages\n");
2213 		return NULL;
2214 	}
2215 	STAILQ_REMOVE_HEAD(&list->free_msgs, link);
2216 	return msg;
2217 }
2218 
2219 static inline void
2220 nvmf_tcp_control_msg_put(struct spdk_nvmf_tcp_control_msg_list *list, void *_msg)
2221 {
2222 	struct spdk_nvmf_tcp_control_msg *msg = _msg;
2223 
2224 	assert(list);
2225 	STAILQ_INSERT_HEAD(&list->free_msgs, msg, link);
2226 }
2227 
2228 static int
2229 nvmf_tcp_req_parse_sgl(struct spdk_nvmf_tcp_req *tcp_req,
2230 		       struct spdk_nvmf_transport *transport,
2231 		       struct spdk_nvmf_transport_poll_group *group)
2232 {
2233 	struct spdk_nvmf_request		*req = &tcp_req->req;
2234 	struct spdk_nvme_cmd			*cmd;
2235 	struct spdk_nvme_cpl			*rsp;
2236 	struct spdk_nvme_sgl_descriptor		*sgl;
2237 	struct spdk_nvmf_tcp_poll_group		*tgroup;
2238 	uint32_t				length;
2239 
2240 	cmd = &req->cmd->nvme_cmd;
2241 	rsp = &req->rsp->nvme_cpl;
2242 	sgl = &cmd->dptr.sgl1;
2243 
2244 	length = sgl->unkeyed.length;
2245 
2246 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK &&
2247 	    sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_TRANSPORT) {
2248 		if (length > transport->opts.max_io_size) {
2249 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
2250 				    length, transport->opts.max_io_size);
2251 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
2252 			return -1;
2253 		}
2254 
2255 		/* fill request length and populate iovs */
2256 		req->length = length;
2257 
2258 		SPDK_DEBUGLOG(nvmf_tcp, "Data requested length= 0x%x\n", length);
2259 
2260 		if (spdk_unlikely(req->dif_enabled)) {
2261 			req->dif.orig_length = length;
2262 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
2263 			req->dif.elba_length = length;
2264 		}
2265 
2266 		if (nvmf_ctrlr_use_zcopy(req)) {
2267 			SPDK_DEBUGLOG(nvmf_tcp, "Using zero-copy to execute request %p\n", tcp_req);
2268 			req->data_from_pool = false;
2269 			return 0;
2270 		}
2271 
2272 		if (spdk_nvmf_request_get_buffers(req, group, transport, length)) {
2273 			/* No available buffers. Queue this request up. */
2274 			SPDK_DEBUGLOG(nvmf_tcp, "No available large data buffers. Queueing request %p\n",
2275 				      tcp_req);
2276 			return 0;
2277 		}
2278 
2279 		/* backward compatible */
2280 		req->data = req->iov[0].iov_base;
2281 
2282 		SPDK_DEBUGLOG(nvmf_tcp, "Request %p took %d buffer/s from central pool, and data=%p\n",
2283 			      tcp_req, req->iovcnt, req->data);
2284 
2285 		return 0;
2286 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
2287 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
2288 		uint64_t offset = sgl->address;
2289 		uint32_t max_len = transport->opts.in_capsule_data_size;
2290 		assert(tcp_req->has_in_capsule_data);
2291 
2292 		SPDK_DEBUGLOG(nvmf_tcp, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
2293 			      offset, length);
2294 
2295 		if (offset > max_len) {
2296 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
2297 				    offset, max_len);
2298 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
2299 			return -1;
2300 		}
2301 		max_len -= (uint32_t)offset;
2302 
2303 		if (spdk_unlikely(length > max_len)) {
2304 			/* According to the SPEC we should support ICD up to 8192 bytes for admin and fabric commands */
2305 			if (length <= SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE &&
2306 			    (cmd->opc == SPDK_NVME_OPC_FABRIC || req->qpair->qid == 0)) {
2307 
2308 				/* Get a buffer from dedicated list */
2309 				SPDK_DEBUGLOG(nvmf_tcp, "Getting a buffer from control msg list\n");
2310 				tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2311 				assert(tgroup->control_msg_list);
2312 				req->data = nvmf_tcp_control_msg_get(tgroup->control_msg_list);
2313 				if (!req->data) {
2314 					/* No available buffers. Queue this request up. */
2315 					SPDK_DEBUGLOG(nvmf_tcp, "No available ICD buffers. Queueing request %p\n", tcp_req);
2316 					return 0;
2317 				}
2318 			} else {
2319 				SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
2320 					    length, max_len);
2321 				rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
2322 				return -1;
2323 			}
2324 		} else {
2325 			req->data = tcp_req->buf;
2326 		}
2327 
2328 		req->length = length;
2329 		req->data_from_pool = false;
2330 
2331 		if (spdk_unlikely(req->dif_enabled)) {
2332 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
2333 			req->dif.elba_length = length;
2334 		}
2335 
2336 		req->iov[0].iov_base = req->data;
2337 		req->iov[0].iov_len = length;
2338 		req->iovcnt = 1;
2339 
2340 		return 0;
2341 	}
2342 
2343 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
2344 		    sgl->generic.type, sgl->generic.subtype);
2345 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
2346 	return -1;
2347 }
2348 
2349 static inline enum spdk_nvme_media_error_status_code
2350 nvmf_tcp_dif_error_to_compl_status(uint8_t err_type) {
2351 	enum spdk_nvme_media_error_status_code result;
2352 
2353 	switch (err_type)
2354 	{
2355 	case SPDK_DIF_REFTAG_ERROR:
2356 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
2357 		break;
2358 	case SPDK_DIF_APPTAG_ERROR:
2359 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
2360 		break;
2361 	case SPDK_DIF_GUARD_ERROR:
2362 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
2363 		break;
2364 	default:
2365 		SPDK_UNREACHABLE();
2366 		break;
2367 	}
2368 
2369 	return result;
2370 }
2371 
2372 static void
2373 _nvmf_tcp_send_c2h_data(struct spdk_nvmf_tcp_qpair *tqpair,
2374 			struct spdk_nvmf_tcp_req *tcp_req)
2375 {
2376 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(
2377 				tqpair->qpair.transport, struct spdk_nvmf_tcp_transport, transport);
2378 	struct nvme_tcp_pdu *rsp_pdu;
2379 	struct spdk_nvme_tcp_c2h_data_hdr *c2h_data;
2380 	uint32_t plen, pdo, alignment;
2381 	int rc;
2382 
2383 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
2384 
2385 	rsp_pdu = tcp_req->pdu;
2386 	assert(rsp_pdu != NULL);
2387 	assert(tcp_req->pdu_in_use);
2388 
2389 	c2h_data = &rsp_pdu->hdr.c2h_data;
2390 	c2h_data->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_C2H_DATA;
2391 	plen = c2h_data->common.hlen = sizeof(*c2h_data);
2392 
2393 	if (tqpair->host_hdgst_enable) {
2394 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2395 		c2h_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
2396 	}
2397 
2398 	/* set the psh */
2399 	c2h_data->cccid = tcp_req->req.cmd->nvme_cmd.cid;
2400 	c2h_data->datal = tcp_req->req.length - tcp_req->pdu->rw_offset;
2401 	c2h_data->datao = tcp_req->pdu->rw_offset;
2402 
2403 	/* set the padding */
2404 	rsp_pdu->padding_len = 0;
2405 	pdo = plen;
2406 	if (tqpair->cpda) {
2407 		alignment = (tqpair->cpda + 1) << 2;
2408 		if (plen % alignment != 0) {
2409 			pdo = (plen + alignment) / alignment * alignment;
2410 			rsp_pdu->padding_len = pdo - plen;
2411 			plen = pdo;
2412 		}
2413 	}
2414 
2415 	c2h_data->common.pdo = pdo;
2416 	plen += c2h_data->datal;
2417 	if (tqpair->host_ddgst_enable) {
2418 		c2h_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_DDGSTF;
2419 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2420 	}
2421 
2422 	c2h_data->common.plen = plen;
2423 
2424 	if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2425 		rsp_pdu->dif_ctx = &tcp_req->req.dif.dif_ctx;
2426 	}
2427 
2428 	nvme_tcp_pdu_set_data_buf(rsp_pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
2429 				  c2h_data->datao, c2h_data->datal);
2430 
2431 
2432 	c2h_data->common.flags |= SPDK_NVME_TCP_C2H_DATA_FLAGS_LAST_PDU;
2433 	/* Need to send the capsule response if response is not all 0 */
2434 	if (ttransport->tcp_opts.c2h_success &&
2435 	    tcp_req->rsp.cdw0 == 0 && tcp_req->rsp.cdw1 == 0) {
2436 		c2h_data->common.flags |= SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS;
2437 	}
2438 
2439 	if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2440 		struct spdk_nvme_cpl *rsp = &tcp_req->req.rsp->nvme_cpl;
2441 		struct spdk_dif_error err_blk = {};
2442 		uint32_t mapped_length = 0;
2443 		uint32_t available_iovs = SPDK_COUNTOF(rsp_pdu->iov);
2444 		uint32_t ddgst_len = 0;
2445 
2446 		if (tqpair->host_ddgst_enable) {
2447 			/* Data digest consumes additional iov entry */
2448 			available_iovs--;
2449 			/* plen needs to be updated since nvme_tcp_build_iovs compares expected and actual plen */
2450 			ddgst_len = SPDK_NVME_TCP_DIGEST_LEN;
2451 			c2h_data->common.plen -= ddgst_len;
2452 		}
2453 		/* Temp call to estimate if data can be described by limited number of iovs.
2454 		 * iov vector will be rebuilt in nvmf_tcp_qpair_write_pdu */
2455 		nvme_tcp_build_iovs(rsp_pdu->iov, available_iovs, rsp_pdu, tqpair->host_hdgst_enable,
2456 				    false, &mapped_length);
2457 
2458 		if (mapped_length != c2h_data->common.plen) {
2459 			c2h_data->datal = mapped_length - (c2h_data->common.plen - c2h_data->datal);
2460 			SPDK_DEBUGLOG(nvmf_tcp,
2461 				      "Part C2H, data_len %u (of %u), PDU len %u, updated PDU len %u, offset %u\n",
2462 				      c2h_data->datal, tcp_req->req.length, c2h_data->common.plen, mapped_length, rsp_pdu->rw_offset);
2463 			c2h_data->common.plen = mapped_length;
2464 
2465 			/* Rebuild pdu->data_iov since data length is changed */
2466 			nvme_tcp_pdu_set_data_buf(rsp_pdu, tcp_req->req.iov, tcp_req->req.iovcnt, c2h_data->datao,
2467 						  c2h_data->datal);
2468 
2469 			c2h_data->common.flags &= ~(SPDK_NVME_TCP_C2H_DATA_FLAGS_LAST_PDU |
2470 						    SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS);
2471 		}
2472 
2473 		c2h_data->common.plen += ddgst_len;
2474 
2475 		assert(rsp_pdu->rw_offset <= tcp_req->req.length);
2476 
2477 		rc = spdk_dif_verify_stream(rsp_pdu->data_iov, rsp_pdu->data_iovcnt,
2478 					    0, rsp_pdu->data_len, rsp_pdu->dif_ctx, &err_blk);
2479 		if (rc != 0) {
2480 			SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n",
2481 				    err_blk.err_type, err_blk.err_offset);
2482 			rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2483 			rsp->status.sc = nvmf_tcp_dif_error_to_compl_status(err_blk.err_type);
2484 			nvmf_tcp_req_pdu_fini(tcp_req);
2485 			nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
2486 			return;
2487 		}
2488 	}
2489 
2490 	rsp_pdu->rw_offset += c2h_data->datal;
2491 	nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, nvmf_tcp_pdu_c2h_data_complete, tcp_req);
2492 }
2493 
2494 static void
2495 nvmf_tcp_send_c2h_data(struct spdk_nvmf_tcp_qpair *tqpair,
2496 		       struct spdk_nvmf_tcp_req *tcp_req)
2497 {
2498 	nvmf_tcp_req_pdu_init(tcp_req);
2499 	_nvmf_tcp_send_c2h_data(tqpair, tcp_req);
2500 }
2501 
2502 static int
2503 request_transfer_out(struct spdk_nvmf_request *req)
2504 {
2505 	struct spdk_nvmf_tcp_req	*tcp_req;
2506 	struct spdk_nvmf_qpair		*qpair;
2507 	struct spdk_nvmf_tcp_qpair	*tqpair;
2508 	struct spdk_nvme_cpl		*rsp;
2509 
2510 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
2511 
2512 	qpair = req->qpair;
2513 	rsp = &req->rsp->nvme_cpl;
2514 	tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
2515 
2516 	/* Advance our sq_head pointer */
2517 	if (qpair->sq_head == qpair->sq_head_max) {
2518 		qpair->sq_head = 0;
2519 	} else {
2520 		qpair->sq_head++;
2521 	}
2522 	rsp->sqhd = qpair->sq_head;
2523 
2524 	tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
2525 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST);
2526 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS && req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2527 		nvmf_tcp_send_c2h_data(tqpair, tcp_req);
2528 	} else {
2529 		nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
2530 	}
2531 
2532 	return 0;
2533 }
2534 
2535 static void
2536 nvmf_tcp_set_in_capsule_data(struct spdk_nvmf_tcp_qpair *tqpair,
2537 			     struct spdk_nvmf_tcp_req *tcp_req)
2538 {
2539 	struct nvme_tcp_pdu *pdu;
2540 	uint32_t plen = 0;
2541 
2542 	pdu = tqpair->pdu_in_progress;
2543 	plen = pdu->hdr.common.hlen;
2544 
2545 	if (tqpair->host_hdgst_enable) {
2546 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2547 	}
2548 
2549 	if (pdu->hdr.common.plen != plen) {
2550 		tcp_req->has_in_capsule_data = true;
2551 	}
2552 }
2553 
2554 static bool
2555 nvmf_tcp_req_process(struct spdk_nvmf_tcp_transport *ttransport,
2556 		     struct spdk_nvmf_tcp_req *tcp_req)
2557 {
2558 	struct spdk_nvmf_tcp_qpair		*tqpair;
2559 	int					rc;
2560 	enum spdk_nvmf_tcp_req_state		prev_state;
2561 	bool					progress = false;
2562 	struct spdk_nvmf_transport		*transport = &ttransport->transport;
2563 	struct spdk_nvmf_transport_poll_group	*group;
2564 	struct spdk_nvmf_tcp_poll_group		*tgroup;
2565 
2566 	tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
2567 	group = &tqpair->group->group;
2568 	assert(tcp_req->state != TCP_REQUEST_STATE_FREE);
2569 
2570 	/* If the qpair is not active, we need to abort the outstanding requests. */
2571 	if (tqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
2572 		if (tcp_req->state == TCP_REQUEST_STATE_NEED_BUFFER) {
2573 			STAILQ_REMOVE(&group->pending_buf_queue, &tcp_req->req, spdk_nvmf_request, buf_link);
2574 		}
2575 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
2576 	}
2577 
2578 	/* The loop here is to allow for several back-to-back state changes. */
2579 	do {
2580 		prev_state = tcp_req->state;
2581 
2582 		SPDK_DEBUGLOG(nvmf_tcp, "Request %p entering state %d on tqpair=%p\n", tcp_req, prev_state,
2583 			      tqpair);
2584 
2585 		switch (tcp_req->state) {
2586 		case TCP_REQUEST_STATE_FREE:
2587 			/* Some external code must kick a request into TCP_REQUEST_STATE_NEW
2588 			 * to escape this state. */
2589 			break;
2590 		case TCP_REQUEST_STATE_NEW:
2591 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_NEW, 0, 0, (uintptr_t)tcp_req, tqpair);
2592 
2593 			/* copy the cmd from the receive pdu */
2594 			tcp_req->cmd = tqpair->pdu_in_progress->hdr.capsule_cmd.ccsqe;
2595 
2596 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&tcp_req->req, &tcp_req->req.dif.dif_ctx))) {
2597 				tcp_req->req.dif_enabled = true;
2598 				tqpair->pdu_in_progress->dif_ctx = &tcp_req->req.dif.dif_ctx;
2599 			}
2600 
2601 			/* The next state transition depends on the data transfer needs of this request. */
2602 			tcp_req->req.xfer = spdk_nvmf_req_get_xfer(&tcp_req->req);
2603 
2604 			if (spdk_unlikely(tcp_req->req.xfer == SPDK_NVME_DATA_BIDIRECTIONAL)) {
2605 				tcp_req->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
2606 				tcp_req->req.rsp->nvme_cpl.status.sc  = SPDK_NVME_SC_INVALID_OPCODE;
2607 				tcp_req->req.rsp->nvme_cpl.cid = tcp_req->req.cmd->nvme_cmd.cid;
2608 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2609 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2610 				SPDK_DEBUGLOG(nvmf_tcp, "Request %p: invalid xfer type (BIDIRECTIONAL)\n", tcp_req);
2611 				break;
2612 			}
2613 
2614 			/* If no data to transfer, ready to execute. */
2615 			if (tcp_req->req.xfer == SPDK_NVME_DATA_NONE) {
2616 				/* Reset the tqpair receiving pdu state */
2617 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2618 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
2619 				break;
2620 			}
2621 
2622 			nvmf_tcp_set_in_capsule_data(tqpair, tcp_req);
2623 
2624 			if (!tcp_req->has_in_capsule_data) {
2625 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2626 			}
2627 
2628 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEED_BUFFER);
2629 			STAILQ_INSERT_TAIL(&group->pending_buf_queue, &tcp_req->req, buf_link);
2630 			break;
2631 		case TCP_REQUEST_STATE_NEED_BUFFER:
2632 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_NEED_BUFFER, 0, 0, (uintptr_t)tcp_req, tqpair);
2633 
2634 			assert(tcp_req->req.xfer != SPDK_NVME_DATA_NONE);
2635 
2636 			if (!tcp_req->has_in_capsule_data && (&tcp_req->req != STAILQ_FIRST(&group->pending_buf_queue))) {
2637 				SPDK_DEBUGLOG(nvmf_tcp,
2638 					      "Not the first element to wait for the buf for tcp_req(%p) on tqpair=%p\n",
2639 					      tcp_req, tqpair);
2640 				/* This request needs to wait in line to obtain a buffer */
2641 				break;
2642 			}
2643 
2644 			/* Try to get a data buffer */
2645 			rc = nvmf_tcp_req_parse_sgl(tcp_req, transport, group);
2646 			if (rc < 0) {
2647 				STAILQ_REMOVE_HEAD(&group->pending_buf_queue, buf_link);
2648 				/* Reset the tqpair receiving pdu state */
2649 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
2650 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2651 				tcp_req->req.rsp->nvme_cpl.cid = tcp_req->req.cmd->nvme_cmd.cid;
2652 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2653 				break;
2654 			}
2655 
2656 			/* Get a zcopy buffer if the request can be serviced through zcopy */
2657 			if (spdk_nvmf_request_using_zcopy(&tcp_req->req)) {
2658 				if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2659 					assert(tcp_req->req.dif.elba_length >= tcp_req->req.length);
2660 					tcp_req->req.length = tcp_req->req.dif.elba_length;
2661 				}
2662 
2663 				STAILQ_REMOVE(&group->pending_buf_queue, &tcp_req->req, spdk_nvmf_request, buf_link);
2664 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_ZCOPY_START);
2665 				spdk_nvmf_request_zcopy_start(&tcp_req->req);
2666 				break;
2667 			}
2668 
2669 			if (!tcp_req->req.data) {
2670 				SPDK_DEBUGLOG(nvmf_tcp, "No buffer allocated for tcp_req(%p) on tqpair(%p\n)",
2671 					      tcp_req, tqpair);
2672 				/* No buffers available. */
2673 				break;
2674 			}
2675 
2676 			STAILQ_REMOVE(&group->pending_buf_queue, &tcp_req->req, spdk_nvmf_request, buf_link);
2677 
2678 			/* If data is transferring from host to controller, we need to do a transfer from the host. */
2679 			if (tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2680 				if (tcp_req->req.data_from_pool) {
2681 					SPDK_DEBUGLOG(nvmf_tcp, "Sending R2T for tcp_req(%p) on tqpair=%p\n", tcp_req, tqpair);
2682 					nvmf_tcp_send_r2t_pdu(tqpair, tcp_req);
2683 				} else {
2684 					struct nvme_tcp_pdu *pdu;
2685 
2686 					nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
2687 
2688 					pdu = tqpair->pdu_in_progress;
2689 					SPDK_DEBUGLOG(nvmf_tcp, "Not need to send r2t for tcp_req(%p) on tqpair=%p\n", tcp_req,
2690 						      tqpair);
2691 					/* No need to send r2t, contained in the capsuled data */
2692 					nvme_tcp_pdu_set_data_buf(pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
2693 								  0, tcp_req->req.length);
2694 					nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
2695 				}
2696 				break;
2697 			}
2698 
2699 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
2700 			break;
2701 		case TCP_REQUEST_STATE_AWAITING_ZCOPY_START:
2702 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_START, 0, 0,
2703 					  (uintptr_t)tcp_req, tqpair);
2704 			/* Some external code must kick a request into  TCP_REQUEST_STATE_ZCOPY_START_COMPLETED
2705 			 * to escape this state. */
2706 			break;
2707 		case TCP_REQUEST_STATE_ZCOPY_START_COMPLETED:
2708 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_ZCOPY_START_COMPLETED, 0, 0,
2709 					  (uintptr_t)tcp_req, tqpair);
2710 			if (spdk_unlikely(spdk_nvme_cpl_is_error(&tcp_req->req.rsp->nvme_cpl))) {
2711 				SPDK_DEBUGLOG(nvmf_tcp, "Zero-copy start failed for tcp_req(%p) on tqpair=%p\n",
2712 					      tcp_req, tqpair);
2713 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2714 				break;
2715 			}
2716 			if (tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2717 				SPDK_DEBUGLOG(nvmf_tcp, "Sending R2T for tcp_req(%p) on tqpair=%p\n", tcp_req, tqpair);
2718 				nvmf_tcp_send_r2t_pdu(tqpair, tcp_req);
2719 			} else {
2720 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTED);
2721 			}
2722 			break;
2723 		case TCP_REQUEST_STATE_AWAITING_R2T_ACK:
2724 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_R2T_ACK, 0, 0, (uintptr_t)tcp_req,
2725 					  tqpair);
2726 			/* The R2T completion or the h2c data incoming will kick it out of this state. */
2727 			break;
2728 		case TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2729 
2730 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2731 					  (uintptr_t)tcp_req, tqpair);
2732 			/* Some external code must kick a request into TCP_REQUEST_STATE_READY_TO_EXECUTE
2733 			 * to escape this state. */
2734 			break;
2735 		case TCP_REQUEST_STATE_READY_TO_EXECUTE:
2736 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE, 0, 0, (uintptr_t)tcp_req,
2737 					  tqpair);
2738 
2739 			if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2740 				assert(tcp_req->req.dif.elba_length >= tcp_req->req.length);
2741 				tcp_req->req.length = tcp_req->req.dif.elba_length;
2742 			}
2743 
2744 			if (!spdk_nvmf_request_using_zcopy(&tcp_req->req)) {
2745 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTING);
2746 				spdk_nvmf_request_exec(&tcp_req->req);
2747 			} else {
2748 				/* For zero-copy, only requests with data coming from host to the
2749 				 * controller can end up here. */
2750 				assert(tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
2751 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT);
2752 				spdk_nvmf_request_zcopy_end(&tcp_req->req, true);
2753 			}
2754 			break;
2755 		case TCP_REQUEST_STATE_EXECUTING:
2756 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_EXECUTING, 0, 0, (uintptr_t)tcp_req, tqpair);
2757 			/* Some external code must kick a request into TCP_REQUEST_STATE_EXECUTED
2758 			 * to escape this state. */
2759 			break;
2760 		case TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT:
2761 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_COMMIT, 0, 0,
2762 					  (uintptr_t)tcp_req, tqpair);
2763 			/* Some external code must kick a request into TCP_REQUEST_STATE_EXECUTED
2764 			 * to escape this state. */
2765 			break;
2766 		case TCP_REQUEST_STATE_EXECUTED:
2767 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_EXECUTED, 0, 0, (uintptr_t)tcp_req, tqpair);
2768 
2769 			if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2770 				tcp_req->req.length = tcp_req->req.dif.orig_length;
2771 			}
2772 
2773 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2774 			break;
2775 		case TCP_REQUEST_STATE_READY_TO_COMPLETE:
2776 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE, 0, 0, (uintptr_t)tcp_req,
2777 					  tqpair);
2778 			rc = request_transfer_out(&tcp_req->req);
2779 			assert(rc == 0); /* No good way to handle this currently */
2780 			break;
2781 		case TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2782 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2783 					  (uintptr_t)tcp_req, tqpair);
2784 			/* Some external code must kick a request into TCP_REQUEST_STATE_COMPLETED
2785 			 * to escape this state. */
2786 			break;
2787 		case TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE:
2788 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_RELEASE, 0, 0,
2789 					  (uintptr_t)tcp_req, tqpair);
2790 			/* Some external code must kick a request into TCP_REQUEST_STATE_COMPLETED
2791 			 * to escape this state. */
2792 			break;
2793 		case TCP_REQUEST_STATE_COMPLETED:
2794 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_COMPLETED, 0, 0, (uintptr_t)tcp_req, tqpair);
2795 			if (tcp_req->req.data_from_pool) {
2796 				spdk_nvmf_request_free_buffers(&tcp_req->req, group, transport);
2797 			} else if (spdk_unlikely(tcp_req->has_in_capsule_data &&
2798 						 (tcp_req->cmd.opc == SPDK_NVME_OPC_FABRIC ||
2799 						  tqpair->qpair.qid == 0) && tcp_req->req.length > transport->opts.in_capsule_data_size)) {
2800 				tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2801 				assert(tgroup->control_msg_list);
2802 				SPDK_DEBUGLOG(nvmf_tcp, "Put buf to control msg list\n");
2803 				nvmf_tcp_control_msg_put(tgroup->control_msg_list, tcp_req->req.data);
2804 			} else if (tcp_req->req.zcopy_bdev_io != NULL) {
2805 				/* If the request has an unreleased zcopy bdev_io, it's either a
2806 				 * read or a failed write */
2807 				assert(spdk_nvmf_request_using_zcopy(&tcp_req->req));
2808 				assert(tcp_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST ||
2809 				       spdk_nvme_cpl_is_error(&tcp_req->req.rsp->nvme_cpl));
2810 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE);
2811 				spdk_nvmf_request_zcopy_end(&tcp_req->req, false);
2812 				break;
2813 			}
2814 			tcp_req->req.length = 0;
2815 			tcp_req->req.iovcnt = 0;
2816 			tcp_req->req.data = NULL;
2817 
2818 			nvmf_tcp_req_pdu_fini(tcp_req);
2819 
2820 			nvmf_tcp_req_put(tqpair, tcp_req);
2821 			break;
2822 		case TCP_REQUEST_NUM_STATES:
2823 		default:
2824 			assert(0);
2825 			break;
2826 		}
2827 
2828 		if (tcp_req->state != prev_state) {
2829 			progress = true;
2830 		}
2831 	} while (tcp_req->state != prev_state);
2832 
2833 	return progress;
2834 }
2835 
2836 static void
2837 nvmf_tcp_sock_cb(void *arg, struct spdk_sock_group *group, struct spdk_sock *sock)
2838 {
2839 	struct spdk_nvmf_tcp_qpair *tqpair = arg;
2840 	int rc;
2841 
2842 	assert(tqpair != NULL);
2843 	rc = nvmf_tcp_sock_process(tqpair);
2844 
2845 	/* If there was a new socket error, disconnect */
2846 	if (rc < 0) {
2847 		nvmf_tcp_qpair_disconnect(tqpair);
2848 	}
2849 }
2850 
2851 static int
2852 nvmf_tcp_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
2853 			struct spdk_nvmf_qpair *qpair)
2854 {
2855 	struct spdk_nvmf_tcp_poll_group	*tgroup;
2856 	struct spdk_nvmf_tcp_qpair	*tqpair;
2857 	int				rc;
2858 
2859 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2860 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
2861 
2862 	rc =  nvmf_tcp_qpair_sock_init(tqpair);
2863 	if (rc != 0) {
2864 		SPDK_ERRLOG("Cannot set sock opt for tqpair=%p\n", tqpair);
2865 		return -1;
2866 	}
2867 
2868 	rc = nvmf_tcp_qpair_init(&tqpair->qpair);
2869 	if (rc < 0) {
2870 		SPDK_ERRLOG("Cannot init tqpair=%p\n", tqpair);
2871 		return -1;
2872 	}
2873 
2874 	rc = nvmf_tcp_qpair_init_mem_resource(tqpair);
2875 	if (rc < 0) {
2876 		SPDK_ERRLOG("Cannot init memory resource info for tqpair=%p\n", tqpair);
2877 		return -1;
2878 	}
2879 
2880 	rc = spdk_sock_group_add_sock(tgroup->sock_group, tqpair->sock,
2881 				      nvmf_tcp_sock_cb, tqpair);
2882 	if (rc != 0) {
2883 		SPDK_ERRLOG("Could not add sock to sock_group: %s (%d)\n",
2884 			    spdk_strerror(errno), errno);
2885 		return -1;
2886 	}
2887 
2888 	tqpair->group = tgroup;
2889 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_INVALID);
2890 	TAILQ_INSERT_TAIL(&tgroup->qpairs, tqpair, link);
2891 
2892 	return 0;
2893 }
2894 
2895 static int
2896 nvmf_tcp_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
2897 			   struct spdk_nvmf_qpair *qpair)
2898 {
2899 	struct spdk_nvmf_tcp_poll_group	*tgroup;
2900 	struct spdk_nvmf_tcp_qpair		*tqpair;
2901 	int				rc;
2902 
2903 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2904 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
2905 
2906 	assert(tqpair->group == tgroup);
2907 
2908 	SPDK_DEBUGLOG(nvmf_tcp, "remove tqpair=%p from the tgroup=%p\n", tqpair, tgroup);
2909 	if (tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_REQ) {
2910 		TAILQ_REMOVE(&tgroup->await_req, tqpair, link);
2911 	} else {
2912 		TAILQ_REMOVE(&tgroup->qpairs, tqpair, link);
2913 	}
2914 
2915 	rc = spdk_sock_group_remove_sock(tgroup->sock_group, tqpair->sock);
2916 	if (rc != 0) {
2917 		SPDK_ERRLOG("Could not remove sock from sock_group: %s (%d)\n",
2918 			    spdk_strerror(errno), errno);
2919 	}
2920 
2921 	return rc;
2922 }
2923 
2924 static int
2925 nvmf_tcp_req_complete(struct spdk_nvmf_request *req)
2926 {
2927 	struct spdk_nvmf_tcp_transport *ttransport;
2928 	struct spdk_nvmf_tcp_req *tcp_req;
2929 
2930 	ttransport = SPDK_CONTAINEROF(req->qpair->transport, struct spdk_nvmf_tcp_transport, transport);
2931 	tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
2932 
2933 	switch (tcp_req->state) {
2934 	case TCP_REQUEST_STATE_EXECUTING:
2935 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT:
2936 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTED);
2937 		break;
2938 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_START:
2939 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_ZCOPY_START_COMPLETED);
2940 		break;
2941 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE:
2942 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
2943 		break;
2944 	default:
2945 		assert(0 && "Unexpected request state");
2946 		break;
2947 	}
2948 
2949 	nvmf_tcp_req_process(ttransport, tcp_req);
2950 
2951 	return 0;
2952 }
2953 
2954 static void
2955 nvmf_tcp_close_qpair(struct spdk_nvmf_qpair *qpair,
2956 		     spdk_nvmf_transport_qpair_fini_cb cb_fn, void *cb_arg)
2957 {
2958 	struct spdk_nvmf_tcp_qpair *tqpair;
2959 
2960 	SPDK_DEBUGLOG(nvmf_tcp, "Qpair: %p\n", qpair);
2961 
2962 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
2963 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_EXITED);
2964 	nvmf_tcp_qpair_destroy(tqpair);
2965 
2966 	if (cb_fn) {
2967 		cb_fn(cb_arg);
2968 	}
2969 }
2970 
2971 static int
2972 nvmf_tcp_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
2973 {
2974 	struct spdk_nvmf_tcp_poll_group *tgroup;
2975 	int rc;
2976 	struct spdk_nvmf_request *req, *req_tmp;
2977 	struct spdk_nvmf_tcp_req *tcp_req;
2978 	struct spdk_nvmf_tcp_qpair *tqpair, *tqpair_tmp;
2979 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(group->transport,
2980 			struct spdk_nvmf_tcp_transport, transport);
2981 
2982 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2983 
2984 	if (spdk_unlikely(TAILQ_EMPTY(&tgroup->qpairs) && TAILQ_EMPTY(&tgroup->await_req))) {
2985 		return 0;
2986 	}
2987 
2988 	STAILQ_FOREACH_SAFE(req, &group->pending_buf_queue, buf_link, req_tmp) {
2989 		tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
2990 		if (nvmf_tcp_req_process(ttransport, tcp_req) == false) {
2991 			break;
2992 		}
2993 	}
2994 
2995 	rc = spdk_sock_group_poll(tgroup->sock_group);
2996 	if (rc < 0) {
2997 		SPDK_ERRLOG("Failed to poll sock_group=%p\n", tgroup->sock_group);
2998 	}
2999 
3000 	TAILQ_FOREACH_SAFE(tqpair, &tgroup->await_req, link, tqpair_tmp) {
3001 		nvmf_tcp_sock_process(tqpair);
3002 	}
3003 
3004 	return rc;
3005 }
3006 
3007 static int
3008 nvmf_tcp_qpair_get_trid(struct spdk_nvmf_qpair *qpair,
3009 			struct spdk_nvme_transport_id *trid, bool peer)
3010 {
3011 	struct spdk_nvmf_tcp_qpair     *tqpair;
3012 	uint16_t			port;
3013 
3014 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3015 	spdk_nvme_trid_populate_transport(trid, SPDK_NVME_TRANSPORT_TCP);
3016 
3017 	if (peer) {
3018 		snprintf(trid->traddr, sizeof(trid->traddr), "%s", tqpair->initiator_addr);
3019 		port = tqpair->initiator_port;
3020 	} else {
3021 		snprintf(trid->traddr, sizeof(trid->traddr), "%s", tqpair->target_addr);
3022 		port = tqpair->target_port;
3023 	}
3024 
3025 	if (spdk_sock_is_ipv4(tqpair->sock)) {
3026 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3027 	} else if (spdk_sock_is_ipv6(tqpair->sock)) {
3028 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3029 	} else {
3030 		return -1;
3031 	}
3032 
3033 	snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%d", port);
3034 	return 0;
3035 }
3036 
3037 static int
3038 nvmf_tcp_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
3039 			      struct spdk_nvme_transport_id *trid)
3040 {
3041 	return nvmf_tcp_qpair_get_trid(qpair, trid, 0);
3042 }
3043 
3044 static int
3045 nvmf_tcp_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
3046 			     struct spdk_nvme_transport_id *trid)
3047 {
3048 	return nvmf_tcp_qpair_get_trid(qpair, trid, 1);
3049 }
3050 
3051 static int
3052 nvmf_tcp_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
3053 			       struct spdk_nvme_transport_id *trid)
3054 {
3055 	return nvmf_tcp_qpair_get_trid(qpair, trid, 0);
3056 }
3057 
3058 static void
3059 nvmf_tcp_req_set_abort_status(struct spdk_nvmf_request *req,
3060 			      struct spdk_nvmf_tcp_req *tcp_req_to_abort)
3061 {
3062 	tcp_req_to_abort->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
3063 	tcp_req_to_abort->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_BY_REQUEST;
3064 	tcp_req_to_abort->req.rsp->nvme_cpl.cid = tcp_req_to_abort->req.cmd->nvme_cmd.cid;
3065 
3066 	nvmf_tcp_req_set_state(tcp_req_to_abort, TCP_REQUEST_STATE_READY_TO_COMPLETE);
3067 
3068 	req->rsp->nvme_cpl.cdw0 &= ~1U; /* Command was successfully aborted. */
3069 }
3070 
3071 static int
3072 _nvmf_tcp_qpair_abort_request(void *ctx)
3073 {
3074 	struct spdk_nvmf_request *req = ctx;
3075 	struct spdk_nvmf_tcp_req *tcp_req_to_abort = SPDK_CONTAINEROF(req->req_to_abort,
3076 			struct spdk_nvmf_tcp_req, req);
3077 	struct spdk_nvmf_tcp_qpair *tqpair = SPDK_CONTAINEROF(req->req_to_abort->qpair,
3078 					     struct spdk_nvmf_tcp_qpair, qpair);
3079 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport,
3080 			struct spdk_nvmf_tcp_transport, transport);
3081 	int rc;
3082 
3083 	spdk_poller_unregister(&req->poller);
3084 
3085 	switch (tcp_req_to_abort->state) {
3086 	case TCP_REQUEST_STATE_EXECUTING:
3087 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_START:
3088 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT:
3089 		rc = nvmf_ctrlr_abort_request(req);
3090 		if (rc == SPDK_NVMF_REQUEST_EXEC_STATUS_ASYNCHRONOUS) {
3091 			return SPDK_POLLER_BUSY;
3092 		}
3093 		break;
3094 
3095 	case TCP_REQUEST_STATE_NEED_BUFFER:
3096 		STAILQ_REMOVE(&tqpair->group->group.pending_buf_queue,
3097 			      &tcp_req_to_abort->req, spdk_nvmf_request, buf_link);
3098 
3099 		nvmf_tcp_req_set_abort_status(req, tcp_req_to_abort);
3100 		nvmf_tcp_req_process(ttransport, tcp_req_to_abort);
3101 		break;
3102 
3103 	case TCP_REQUEST_STATE_AWAITING_R2T_ACK:
3104 	case TCP_REQUEST_STATE_ZCOPY_START_COMPLETED:
3105 		nvmf_tcp_req_set_abort_status(req, tcp_req_to_abort);
3106 		break;
3107 
3108 	case TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
3109 		if (spdk_get_ticks() < req->timeout_tsc) {
3110 			req->poller = SPDK_POLLER_REGISTER(_nvmf_tcp_qpair_abort_request, req, 0);
3111 			return SPDK_POLLER_BUSY;
3112 		}
3113 		break;
3114 
3115 	default:
3116 		break;
3117 	}
3118 
3119 	spdk_nvmf_request_complete(req);
3120 	return SPDK_POLLER_BUSY;
3121 }
3122 
3123 static void
3124 nvmf_tcp_qpair_abort_request(struct spdk_nvmf_qpair *qpair,
3125 			     struct spdk_nvmf_request *req)
3126 {
3127 	struct spdk_nvmf_tcp_qpair *tqpair;
3128 	struct spdk_nvmf_tcp_transport *ttransport;
3129 	struct spdk_nvmf_transport *transport;
3130 	uint16_t cid;
3131 	uint32_t i;
3132 	struct spdk_nvmf_tcp_req *tcp_req_to_abort = NULL;
3133 
3134 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3135 	ttransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_tcp_transport, transport);
3136 	transport = &ttransport->transport;
3137 
3138 	cid = req->cmd->nvme_cmd.cdw10_bits.abort.cid;
3139 
3140 	for (i = 0; i < tqpair->resource_count; i++) {
3141 		if (tqpair->reqs[i].state != TCP_REQUEST_STATE_FREE &&
3142 		    tqpair->reqs[i].req.cmd->nvme_cmd.cid == cid) {
3143 			tcp_req_to_abort = &tqpair->reqs[i];
3144 			break;
3145 		}
3146 	}
3147 
3148 	spdk_trace_record(TRACE_TCP_QP_ABORT_REQ, 0, 0, (uintptr_t)req, tqpair);
3149 
3150 	if (tcp_req_to_abort == NULL) {
3151 		spdk_nvmf_request_complete(req);
3152 		return;
3153 	}
3154 
3155 	req->req_to_abort = &tcp_req_to_abort->req;
3156 	req->timeout_tsc = spdk_get_ticks() +
3157 			   transport->opts.abort_timeout_sec * spdk_get_ticks_hz();
3158 	req->poller = NULL;
3159 
3160 	_nvmf_tcp_qpair_abort_request(req);
3161 }
3162 
3163 #define SPDK_NVMF_TCP_DEFAULT_MAX_QUEUE_DEPTH 128
3164 #define SPDK_NVMF_TCP_DEFAULT_AQ_DEPTH 128
3165 #define SPDK_NVMF_TCP_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
3166 #define SPDK_NVMF_TCP_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
3167 #define SPDK_NVMF_TCP_DEFAULT_MAX_IO_SIZE 131072
3168 #define SPDK_NVMF_TCP_DEFAULT_IO_UNIT_SIZE 131072
3169 #define SPDK_NVMF_TCP_DEFAULT_NUM_SHARED_BUFFERS 511
3170 #define SPDK_NVMF_TCP_DEFAULT_BUFFER_CACHE_SIZE 32
3171 #define SPDK_NVMF_TCP_DEFAULT_DIF_INSERT_OR_STRIP false
3172 #define SPDK_NVMF_TCP_DEFAULT_ABORT_TIMEOUT_SEC 1
3173 
3174 static void
3175 nvmf_tcp_opts_init(struct spdk_nvmf_transport_opts *opts)
3176 {
3177 	opts->max_queue_depth =		SPDK_NVMF_TCP_DEFAULT_MAX_QUEUE_DEPTH;
3178 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_TCP_DEFAULT_MAX_QPAIRS_PER_CTRLR;
3179 	opts->in_capsule_data_size =	SPDK_NVMF_TCP_DEFAULT_IN_CAPSULE_DATA_SIZE;
3180 	opts->max_io_size =		SPDK_NVMF_TCP_DEFAULT_MAX_IO_SIZE;
3181 	opts->io_unit_size =		SPDK_NVMF_TCP_DEFAULT_IO_UNIT_SIZE;
3182 	opts->max_aq_depth =		SPDK_NVMF_TCP_DEFAULT_AQ_DEPTH;
3183 	opts->num_shared_buffers =	SPDK_NVMF_TCP_DEFAULT_NUM_SHARED_BUFFERS;
3184 	opts->buf_cache_size =		SPDK_NVMF_TCP_DEFAULT_BUFFER_CACHE_SIZE;
3185 	opts->dif_insert_or_strip =	SPDK_NVMF_TCP_DEFAULT_DIF_INSERT_OR_STRIP;
3186 	opts->abort_timeout_sec =	SPDK_NVMF_TCP_DEFAULT_ABORT_TIMEOUT_SEC;
3187 	opts->transport_specific =      NULL;
3188 }
3189 
3190 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_tcp = {
3191 	.name = "TCP",
3192 	.type = SPDK_NVME_TRANSPORT_TCP,
3193 	.opts_init = nvmf_tcp_opts_init,
3194 	.create = nvmf_tcp_create,
3195 	.dump_opts = nvmf_tcp_dump_opts,
3196 	.destroy = nvmf_tcp_destroy,
3197 
3198 	.listen = nvmf_tcp_listen,
3199 	.stop_listen = nvmf_tcp_stop_listen,
3200 
3201 	.listener_discover = nvmf_tcp_discover,
3202 
3203 	.poll_group_create = nvmf_tcp_poll_group_create,
3204 	.get_optimal_poll_group = nvmf_tcp_get_optimal_poll_group,
3205 	.poll_group_destroy = nvmf_tcp_poll_group_destroy,
3206 	.poll_group_add = nvmf_tcp_poll_group_add,
3207 	.poll_group_remove = nvmf_tcp_poll_group_remove,
3208 	.poll_group_poll = nvmf_tcp_poll_group_poll,
3209 
3210 	.req_free = nvmf_tcp_req_free,
3211 	.req_complete = nvmf_tcp_req_complete,
3212 
3213 	.qpair_fini = nvmf_tcp_close_qpair,
3214 	.qpair_get_local_trid = nvmf_tcp_qpair_get_local_trid,
3215 	.qpair_get_peer_trid = nvmf_tcp_qpair_get_peer_trid,
3216 	.qpair_get_listen_trid = nvmf_tcp_qpair_get_listen_trid,
3217 	.qpair_abort_request = nvmf_tcp_qpair_abort_request,
3218 };
3219 
3220 SPDK_NVMF_TRANSPORT_REGISTER(tcp, &spdk_nvmf_transport_tcp);
3221 SPDK_LOG_REGISTER_COMPONENT(nvmf_tcp)
3222