xref: /spdk/lib/nvmf/tcp.c (revision 099bdaf3b5279bca62858c8e68e3d0cd331cb9ad)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (C) 2018 Intel Corporation. All rights reserved.
3  *   Copyright (c) 2019, 2020 Mellanox Technologies LTD. All rights reserved.
4  *   Copyright (c) 2022 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
5  */
6 
7 #include "spdk/accel.h"
8 #include "spdk/stdinc.h"
9 #include "spdk/crc32.h"
10 #include "spdk/endian.h"
11 #include "spdk/assert.h"
12 #include "spdk/thread.h"
13 #include "spdk/nvmf_transport.h"
14 #include "spdk/string.h"
15 #include "spdk/trace.h"
16 #include "spdk/util.h"
17 #include "spdk/log.h"
18 
19 #include "spdk_internal/assert.h"
20 #include "spdk_internal/nvme_tcp.h"
21 #include "spdk_internal/sock.h"
22 
23 #include "nvmf_internal.h"
24 
25 #include "spdk_internal/trace_defs.h"
26 
27 #define NVMF_TCP_MAX_ACCEPT_SOCK_ONE_TIME 16
28 #define SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY 16
29 #define SPDK_NVMF_TCP_DEFAULT_SOCK_PRIORITY 0
30 #define SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM 32
31 #define SPDK_NVMF_TCP_DEFAULT_SUCCESS_OPTIMIZATION true
32 
33 #define SPDK_NVMF_TCP_MIN_IO_QUEUE_DEPTH 2
34 #define SPDK_NVMF_TCP_MAX_IO_QUEUE_DEPTH 65535
35 #define SPDK_NVMF_TCP_MIN_ADMIN_QUEUE_DEPTH 2
36 #define SPDK_NVMF_TCP_MAX_ADMIN_QUEUE_DEPTH 4096
37 
38 #define SPDK_NVMF_TCP_DEFAULT_MAX_IO_QUEUE_DEPTH 128
39 #define SPDK_NVMF_TCP_DEFAULT_MAX_ADMIN_QUEUE_DEPTH 128
40 #define SPDK_NVMF_TCP_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
41 #define SPDK_NVMF_TCP_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
42 #define SPDK_NVMF_TCP_DEFAULT_MAX_IO_SIZE 131072
43 #define SPDK_NVMF_TCP_DEFAULT_IO_UNIT_SIZE 131072
44 #define SPDK_NVMF_TCP_DEFAULT_NUM_SHARED_BUFFERS 511
45 #define SPDK_NVMF_TCP_DEFAULT_BUFFER_CACHE_SIZE UINT32_MAX
46 #define SPDK_NVMF_TCP_DEFAULT_DIF_INSERT_OR_STRIP false
47 #define SPDK_NVMF_TCP_DEFAULT_ABORT_TIMEOUT_SEC 1
48 
49 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_tcp;
50 
51 /* spdk nvmf related structure */
52 enum spdk_nvmf_tcp_req_state {
53 
54 	/* The request is not currently in use */
55 	TCP_REQUEST_STATE_FREE = 0,
56 
57 	/* Initial state when request first received */
58 	TCP_REQUEST_STATE_NEW = 1,
59 
60 	/* The request is queued until a data buffer is available. */
61 	TCP_REQUEST_STATE_NEED_BUFFER = 2,
62 
63 	/* The request is waiting for zcopy_start to finish */
64 	TCP_REQUEST_STATE_AWAITING_ZCOPY_START = 3,
65 
66 	/* The request has received a zero-copy buffer */
67 	TCP_REQUEST_STATE_ZCOPY_START_COMPLETED = 4,
68 
69 	/* The request is currently transferring data from the host to the controller. */
70 	TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER = 5,
71 
72 	/* The request is waiting for the R2T send acknowledgement. */
73 	TCP_REQUEST_STATE_AWAITING_R2T_ACK = 6,
74 
75 	/* The request is ready to execute at the block device */
76 	TCP_REQUEST_STATE_READY_TO_EXECUTE = 7,
77 
78 	/* The request is currently executing at the block device */
79 	TCP_REQUEST_STATE_EXECUTING = 8,
80 
81 	/* The request is waiting for zcopy buffers to be committed */
82 	TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT = 9,
83 
84 	/* The request finished executing at the block device */
85 	TCP_REQUEST_STATE_EXECUTED = 10,
86 
87 	/* The request is ready to send a completion */
88 	TCP_REQUEST_STATE_READY_TO_COMPLETE = 11,
89 
90 	/* The request is currently transferring final pdus from the controller to the host. */
91 	TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST = 12,
92 
93 	/* The request is waiting for zcopy buffers to be released (without committing) */
94 	TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE = 13,
95 
96 	/* The request completed and can be marked free. */
97 	TCP_REQUEST_STATE_COMPLETED = 14,
98 
99 	/* Terminator */
100 	TCP_REQUEST_NUM_STATES,
101 };
102 
103 static const char *spdk_nvmf_tcp_term_req_fes_str[] = {
104 	"Invalid PDU Header Field",
105 	"PDU Sequence Error",
106 	"Header Digiest Error",
107 	"Data Transfer Out of Range",
108 	"R2T Limit Exceeded",
109 	"Unsupported parameter",
110 };
111 
112 SPDK_TRACE_REGISTER_FN(nvmf_tcp_trace, "nvmf_tcp", TRACE_GROUP_NVMF_TCP)
113 {
114 	spdk_trace_register_owner(OWNER_NVMF_TCP, 't');
115 	spdk_trace_register_object(OBJECT_NVMF_TCP_IO, 'r');
116 	spdk_trace_register_description("TCP_REQ_NEW",
117 					TRACE_TCP_REQUEST_STATE_NEW,
118 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 1,
119 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
120 	spdk_trace_register_description("TCP_REQ_NEED_BUFFER",
121 					TRACE_TCP_REQUEST_STATE_NEED_BUFFER,
122 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
123 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
124 	spdk_trace_register_description("TCP_REQ_WAIT_ZCPY_START",
125 					TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_START,
126 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
127 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
128 	spdk_trace_register_description("TCP_REQ_ZCPY_START_CPL",
129 					TRACE_TCP_REQUEST_STATE_ZCOPY_START_COMPLETED,
130 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
131 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
132 	spdk_trace_register_description("TCP_REQ_TX_H_TO_C",
133 					TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
134 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
135 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
136 	spdk_trace_register_description("TCP_REQ_RDY_TO_EXECUTE",
137 					TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE,
138 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
139 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
140 	spdk_trace_register_description("TCP_REQ_EXECUTING",
141 					TRACE_TCP_REQUEST_STATE_EXECUTING,
142 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
143 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
144 	spdk_trace_register_description("TCP_REQ_WAIT_ZCPY_CMT",
145 					TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_COMMIT,
146 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
147 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
148 	spdk_trace_register_description("TCP_REQ_EXECUTED",
149 					TRACE_TCP_REQUEST_STATE_EXECUTED,
150 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
151 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
152 	spdk_trace_register_description("TCP_REQ_RDY_TO_COMPLETE",
153 					TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE,
154 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
155 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
156 	spdk_trace_register_description("TCP_REQ_TRANSFER_C2H",
157 					TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
158 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
159 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
160 	spdk_trace_register_description("TCP_REQ_AWAIT_ZCPY_RLS",
161 					TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_RELEASE,
162 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
163 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
164 	spdk_trace_register_description("TCP_REQ_COMPLETED",
165 					TRACE_TCP_REQUEST_STATE_COMPLETED,
166 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
167 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
168 	spdk_trace_register_description("TCP_WRITE_START",
169 					TRACE_TCP_FLUSH_WRITEBUF_START,
170 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
171 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
172 	spdk_trace_register_description("TCP_WRITE_DONE",
173 					TRACE_TCP_FLUSH_WRITEBUF_DONE,
174 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
175 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
176 	spdk_trace_register_description("TCP_READ_DONE",
177 					TRACE_TCP_READ_FROM_SOCKET_DONE,
178 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
179 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
180 	spdk_trace_register_description("TCP_REQ_AWAIT_R2T_ACK",
181 					TRACE_TCP_REQUEST_STATE_AWAIT_R2T_ACK,
182 					OWNER_NVMF_TCP, OBJECT_NVMF_TCP_IO, 0,
183 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
184 
185 	spdk_trace_register_description("TCP_QP_CREATE", TRACE_TCP_QP_CREATE,
186 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
187 					SPDK_TRACE_ARG_TYPE_INT, "");
188 	spdk_trace_register_description("TCP_QP_SOCK_INIT", TRACE_TCP_QP_SOCK_INIT,
189 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
190 					SPDK_TRACE_ARG_TYPE_INT, "");
191 	spdk_trace_register_description("TCP_QP_STATE_CHANGE", TRACE_TCP_QP_STATE_CHANGE,
192 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
193 					SPDK_TRACE_ARG_TYPE_INT, "state");
194 	spdk_trace_register_description("TCP_QP_DISCONNECT", TRACE_TCP_QP_DISCONNECT,
195 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
196 					SPDK_TRACE_ARG_TYPE_INT, "");
197 	spdk_trace_register_description("TCP_QP_DESTROY", TRACE_TCP_QP_DESTROY,
198 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
199 					SPDK_TRACE_ARG_TYPE_INT, "");
200 	spdk_trace_register_description("TCP_QP_ABORT_REQ", TRACE_TCP_QP_ABORT_REQ,
201 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
202 					SPDK_TRACE_ARG_TYPE_PTR, "qpair");
203 	spdk_trace_register_description("TCP_QP_RCV_STATE_CHANGE", TRACE_TCP_QP_RCV_STATE_CHANGE,
204 					OWNER_NVMF_TCP, OBJECT_NONE, 0,
205 					SPDK_TRACE_ARG_TYPE_INT, "state");
206 
207 	spdk_trace_tpoint_register_relation(TRACE_BDEV_IO_START, OBJECT_NVMF_TCP_IO, 1);
208 	spdk_trace_tpoint_register_relation(TRACE_BDEV_IO_DONE, OBJECT_NVMF_TCP_IO, 0);
209 }
210 
211 struct spdk_nvmf_tcp_req  {
212 	struct spdk_nvmf_request		req;
213 	struct spdk_nvme_cpl			rsp;
214 	struct spdk_nvme_cmd			cmd;
215 
216 	/* A PDU that can be used for sending responses. This is
217 	 * not the incoming PDU! */
218 	struct nvme_tcp_pdu			*pdu;
219 
220 	/* In-capsule data buffer */
221 	uint8_t					*buf;
222 
223 	struct spdk_nvmf_tcp_req		*fused_pair;
224 
225 	/*
226 	 * The PDU for a request may be used multiple times in serial over
227 	 * the request's lifetime. For example, first to send an R2T, then
228 	 * to send a completion. To catch mistakes where the PDU is used
229 	 * twice at the same time, add a debug flag here for init/fini.
230 	 */
231 	bool					pdu_in_use;
232 	bool					has_in_capsule_data;
233 	bool					fused_failed;
234 
235 	/* transfer_tag */
236 	uint16_t				ttag;
237 
238 	enum spdk_nvmf_tcp_req_state		state;
239 
240 	/*
241 	 * h2c_offset is used when we receive the h2c_data PDU.
242 	 */
243 	uint32_t				h2c_offset;
244 
245 	STAILQ_ENTRY(spdk_nvmf_tcp_req)		link;
246 	TAILQ_ENTRY(spdk_nvmf_tcp_req)		state_link;
247 };
248 
249 struct spdk_nvmf_tcp_qpair {
250 	struct spdk_nvmf_qpair			qpair;
251 	struct spdk_nvmf_tcp_poll_group		*group;
252 	struct spdk_sock			*sock;
253 
254 	enum nvme_tcp_pdu_recv_state		recv_state;
255 	enum nvme_tcp_qpair_state		state;
256 
257 	/* PDU being actively received */
258 	struct nvme_tcp_pdu			*pdu_in_progress;
259 
260 	struct spdk_nvmf_tcp_req		*fused_first;
261 
262 	/* Queues to track the requests in all states */
263 	TAILQ_HEAD(, spdk_nvmf_tcp_req)		tcp_req_working_queue;
264 	TAILQ_HEAD(, spdk_nvmf_tcp_req)		tcp_req_free_queue;
265 	SLIST_HEAD(, nvme_tcp_pdu)		tcp_pdu_free_queue;
266 
267 	/* Number of requests in each state */
268 	uint32_t				state_cntr[TCP_REQUEST_NUM_STATES];
269 
270 	uint8_t					cpda;
271 
272 	bool					host_hdgst_enable;
273 	bool					host_ddgst_enable;
274 
275 	/* This is a spare PDU used for sending special management
276 	 * operations. Primarily, this is used for the initial
277 	 * connection response and c2h termination request. */
278 	struct nvme_tcp_pdu			*mgmt_pdu;
279 
280 	/* Arrays of in-capsule buffers, requests, and pdus.
281 	 * Each array is 'resource_count' number of elements */
282 	void					*bufs;
283 	struct spdk_nvmf_tcp_req		*reqs;
284 	struct nvme_tcp_pdu			*pdus;
285 	uint32_t				resource_count;
286 	uint32_t				recv_buf_size;
287 
288 	struct spdk_nvmf_tcp_port		*port;
289 
290 	/* IP address */
291 	char					initiator_addr[SPDK_NVMF_TRADDR_MAX_LEN];
292 	char					target_addr[SPDK_NVMF_TRADDR_MAX_LEN];
293 
294 	/* IP port */
295 	uint16_t				initiator_port;
296 	uint16_t				target_port;
297 
298 	/* Timer used to destroy qpair after detecting transport error issue if initiator does
299 	 *  not close the connection.
300 	 */
301 	struct spdk_poller			*timeout_poller;
302 
303 	spdk_nvmf_transport_qpair_fini_cb	fini_cb_fn;
304 	void					*fini_cb_arg;
305 
306 	TAILQ_ENTRY(spdk_nvmf_tcp_qpair)	link;
307 };
308 
309 struct spdk_nvmf_tcp_control_msg {
310 	STAILQ_ENTRY(spdk_nvmf_tcp_control_msg) link;
311 };
312 
313 struct spdk_nvmf_tcp_control_msg_list {
314 	void *msg_buf;
315 	STAILQ_HEAD(, spdk_nvmf_tcp_control_msg) free_msgs;
316 };
317 
318 struct spdk_nvmf_tcp_poll_group {
319 	struct spdk_nvmf_transport_poll_group	group;
320 	struct spdk_sock_group			*sock_group;
321 
322 	TAILQ_HEAD(, spdk_nvmf_tcp_qpair)	qpairs;
323 	TAILQ_HEAD(, spdk_nvmf_tcp_qpair)	await_req;
324 
325 	struct spdk_io_channel			*accel_channel;
326 	struct spdk_nvmf_tcp_control_msg_list	*control_msg_list;
327 
328 	TAILQ_ENTRY(spdk_nvmf_tcp_poll_group)	link;
329 };
330 
331 struct spdk_nvmf_tcp_port {
332 	const struct spdk_nvme_transport_id	*trid;
333 	struct spdk_sock			*listen_sock;
334 	TAILQ_ENTRY(spdk_nvmf_tcp_port)		link;
335 };
336 
337 struct tcp_transport_opts {
338 	bool		c2h_success;
339 	uint16_t	control_msg_num;
340 	uint32_t	sock_priority;
341 };
342 
343 struct spdk_nvmf_tcp_transport {
344 	struct spdk_nvmf_transport		transport;
345 	struct tcp_transport_opts               tcp_opts;
346 
347 	struct spdk_nvmf_tcp_poll_group		*next_pg;
348 
349 	struct spdk_poller			*accept_poller;
350 
351 	TAILQ_HEAD(, spdk_nvmf_tcp_port)	ports;
352 	TAILQ_HEAD(, spdk_nvmf_tcp_poll_group)	poll_groups;
353 };
354 
355 static const struct spdk_json_object_decoder tcp_transport_opts_decoder[] = {
356 	{
357 		"c2h_success", offsetof(struct tcp_transport_opts, c2h_success),
358 		spdk_json_decode_bool, true
359 	},
360 	{
361 		"control_msg_num", offsetof(struct tcp_transport_opts, control_msg_num),
362 		spdk_json_decode_uint16, true
363 	},
364 	{
365 		"sock_priority", offsetof(struct tcp_transport_opts, sock_priority),
366 		spdk_json_decode_uint32, true
367 	},
368 };
369 
370 static bool nvmf_tcp_req_process(struct spdk_nvmf_tcp_transport *ttransport,
371 				 struct spdk_nvmf_tcp_req *tcp_req);
372 static void nvmf_tcp_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group);
373 
374 static void _nvmf_tcp_send_c2h_data(struct spdk_nvmf_tcp_qpair *tqpair,
375 				    struct spdk_nvmf_tcp_req *tcp_req);
376 
377 static inline void
378 nvmf_tcp_req_set_state(struct spdk_nvmf_tcp_req *tcp_req,
379 		       enum spdk_nvmf_tcp_req_state state)
380 {
381 	struct spdk_nvmf_qpair *qpair;
382 	struct spdk_nvmf_tcp_qpair *tqpair;
383 
384 	qpair = tcp_req->req.qpair;
385 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
386 
387 	assert(tqpair->state_cntr[tcp_req->state] > 0);
388 	tqpair->state_cntr[tcp_req->state]--;
389 	tqpair->state_cntr[state]++;
390 
391 	tcp_req->state = state;
392 }
393 
394 static inline struct nvme_tcp_pdu *
395 nvmf_tcp_req_pdu_init(struct spdk_nvmf_tcp_req *tcp_req)
396 {
397 	assert(tcp_req->pdu_in_use == false);
398 
399 	memset(tcp_req->pdu, 0, sizeof(*tcp_req->pdu));
400 	tcp_req->pdu->qpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
401 
402 	return tcp_req->pdu;
403 }
404 
405 static struct spdk_nvmf_tcp_req *
406 nvmf_tcp_req_get(struct spdk_nvmf_tcp_qpair *tqpair)
407 {
408 	struct spdk_nvmf_tcp_req *tcp_req;
409 
410 	tcp_req = TAILQ_FIRST(&tqpair->tcp_req_free_queue);
411 	if (spdk_unlikely(!tcp_req)) {
412 		return NULL;
413 	}
414 
415 	memset(&tcp_req->rsp, 0, sizeof(tcp_req->rsp));
416 	tcp_req->h2c_offset = 0;
417 	tcp_req->has_in_capsule_data = false;
418 	tcp_req->req.dif_enabled = false;
419 	tcp_req->req.zcopy_phase = NVMF_ZCOPY_PHASE_NONE;
420 
421 	TAILQ_REMOVE(&tqpair->tcp_req_free_queue, tcp_req, state_link);
422 	TAILQ_INSERT_TAIL(&tqpair->tcp_req_working_queue, tcp_req, state_link);
423 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEW);
424 	return tcp_req;
425 }
426 
427 static inline void
428 nvmf_tcp_req_put(struct spdk_nvmf_tcp_qpair *tqpair, struct spdk_nvmf_tcp_req *tcp_req)
429 {
430 	assert(!tcp_req->pdu_in_use);
431 
432 	TAILQ_REMOVE(&tqpair->tcp_req_working_queue, tcp_req, state_link);
433 	TAILQ_INSERT_TAIL(&tqpair->tcp_req_free_queue, tcp_req, state_link);
434 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_FREE);
435 }
436 
437 static void
438 nvmf_tcp_request_free(void *cb_arg)
439 {
440 	struct spdk_nvmf_tcp_transport *ttransport;
441 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
442 
443 	assert(tcp_req != NULL);
444 
445 	SPDK_DEBUGLOG(nvmf_tcp, "tcp_req=%p will be freed\n", tcp_req);
446 	ttransport = SPDK_CONTAINEROF(tcp_req->req.qpair->transport,
447 				      struct spdk_nvmf_tcp_transport, transport);
448 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
449 	nvmf_tcp_req_process(ttransport, tcp_req);
450 }
451 
452 static int
453 nvmf_tcp_req_free(struct spdk_nvmf_request *req)
454 {
455 	struct spdk_nvmf_tcp_req *tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
456 
457 	nvmf_tcp_request_free(tcp_req);
458 
459 	return 0;
460 }
461 
462 static void
463 nvmf_tcp_drain_state_queue(struct spdk_nvmf_tcp_qpair *tqpair,
464 			   enum spdk_nvmf_tcp_req_state state)
465 {
466 	struct spdk_nvmf_tcp_req *tcp_req, *req_tmp;
467 
468 	assert(state != TCP_REQUEST_STATE_FREE);
469 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->tcp_req_working_queue, state_link, req_tmp) {
470 		if (state == tcp_req->state) {
471 			nvmf_tcp_request_free(tcp_req);
472 		}
473 	}
474 }
475 
476 static void
477 nvmf_tcp_cleanup_all_states(struct spdk_nvmf_tcp_qpair *tqpair)
478 {
479 	struct spdk_nvmf_tcp_req *tcp_req, *req_tmp;
480 
481 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST);
482 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_NEW);
483 
484 	/* Wipe the requests waiting for buffer from the global list */
485 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->tcp_req_working_queue, state_link, req_tmp) {
486 		if (tcp_req->state == TCP_REQUEST_STATE_NEED_BUFFER) {
487 			STAILQ_REMOVE(&tqpair->group->group.pending_buf_queue, &tcp_req->req,
488 				      spdk_nvmf_request, buf_link);
489 		}
490 	}
491 
492 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_NEED_BUFFER);
493 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_EXECUTING);
494 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
495 	nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_AWAITING_R2T_ACK);
496 }
497 
498 static void
499 nvmf_tcp_dump_qpair_req_contents(struct spdk_nvmf_tcp_qpair *tqpair)
500 {
501 	int i;
502 	struct spdk_nvmf_tcp_req *tcp_req;
503 
504 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", tqpair->qpair.qid);
505 	for (i = 1; i < TCP_REQUEST_NUM_STATES; i++) {
506 		SPDK_ERRLOG("\tNum of requests in state[%d] = %u\n", i, tqpair->state_cntr[i]);
507 		TAILQ_FOREACH(tcp_req, &tqpair->tcp_req_working_queue, state_link) {
508 			if ((int)tcp_req->state == i) {
509 				SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", tcp_req->req.data_from_pool);
510 				SPDK_ERRLOG("\t\tRequest opcode: %d\n", tcp_req->req.cmd->nvmf_cmd.opcode);
511 			}
512 		}
513 	}
514 }
515 
516 static void
517 _nvmf_tcp_qpair_destroy(void *_tqpair)
518 {
519 	struct spdk_nvmf_tcp_qpair *tqpair = _tqpair;
520 	spdk_nvmf_transport_qpair_fini_cb cb_fn = tqpair->fini_cb_fn;
521 	void *cb_arg = tqpair->fini_cb_arg;
522 	int err = 0;
523 
524 	spdk_trace_record(TRACE_TCP_QP_DESTROY, 0, 0, (uintptr_t)tqpair);
525 
526 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
527 
528 	err = spdk_sock_close(&tqpair->sock);
529 	assert(err == 0);
530 	nvmf_tcp_cleanup_all_states(tqpair);
531 
532 	if (tqpair->state_cntr[TCP_REQUEST_STATE_FREE] != tqpair->resource_count) {
533 		SPDK_ERRLOG("tqpair(%p) free tcp request num is %u but should be %u\n", tqpair,
534 			    tqpair->state_cntr[TCP_REQUEST_STATE_FREE],
535 			    tqpair->resource_count);
536 		err++;
537 	}
538 
539 	if (err > 0) {
540 		nvmf_tcp_dump_qpair_req_contents(tqpair);
541 	}
542 
543 	/* The timeout poller might still be registered here if we close the qpair before host
544 	 * terminates the connection.
545 	 */
546 	spdk_poller_unregister(&tqpair->timeout_poller);
547 	spdk_dma_free(tqpair->pdus);
548 	free(tqpair->reqs);
549 	spdk_free(tqpair->bufs);
550 	free(tqpair);
551 
552 	if (cb_fn != NULL) {
553 		cb_fn(cb_arg);
554 	}
555 
556 	SPDK_DEBUGLOG(nvmf_tcp, "Leave\n");
557 }
558 
559 static void
560 nvmf_tcp_qpair_destroy(struct spdk_nvmf_tcp_qpair *tqpair)
561 {
562 	/* Delay the destruction to make sure it isn't performed from the context of a sock
563 	 * callback.  Otherwise, spdk_sock_close() might not abort pending requests, causing their
564 	 * completions to be executed after the qpair is freed.  (Note: this fixed issue #2471.)
565 	 */
566 	spdk_thread_send_msg(spdk_get_thread(), _nvmf_tcp_qpair_destroy, tqpair);
567 }
568 
569 static void
570 nvmf_tcp_dump_opts(struct spdk_nvmf_transport *transport, struct spdk_json_write_ctx *w)
571 {
572 	struct spdk_nvmf_tcp_transport	*ttransport;
573 	assert(w != NULL);
574 
575 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
576 	spdk_json_write_named_bool(w, "c2h_success", ttransport->tcp_opts.c2h_success);
577 	spdk_json_write_named_uint32(w, "sock_priority", ttransport->tcp_opts.sock_priority);
578 }
579 
580 static int
581 nvmf_tcp_destroy(struct spdk_nvmf_transport *transport,
582 		 spdk_nvmf_transport_destroy_done_cb cb_fn, void *cb_arg)
583 {
584 	struct spdk_nvmf_tcp_transport	*ttransport;
585 
586 	assert(transport != NULL);
587 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
588 
589 	spdk_poller_unregister(&ttransport->accept_poller);
590 	free(ttransport);
591 
592 	if (cb_fn) {
593 		cb_fn(cb_arg);
594 	}
595 	return 0;
596 }
597 
598 static int nvmf_tcp_accept(void *ctx);
599 
600 static struct spdk_nvmf_transport *
601 nvmf_tcp_create(struct spdk_nvmf_transport_opts *opts)
602 {
603 	struct spdk_nvmf_tcp_transport *ttransport;
604 	uint32_t sge_count;
605 	uint32_t min_shared_buffers;
606 
607 	ttransport = calloc(1, sizeof(*ttransport));
608 	if (!ttransport) {
609 		return NULL;
610 	}
611 
612 	TAILQ_INIT(&ttransport->ports);
613 	TAILQ_INIT(&ttransport->poll_groups);
614 
615 	ttransport->transport.ops = &spdk_nvmf_transport_tcp;
616 
617 	ttransport->tcp_opts.c2h_success = SPDK_NVMF_TCP_DEFAULT_SUCCESS_OPTIMIZATION;
618 	ttransport->tcp_opts.sock_priority = SPDK_NVMF_TCP_DEFAULT_SOCK_PRIORITY;
619 	ttransport->tcp_opts.control_msg_num = SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM;
620 	if (opts->transport_specific != NULL &&
621 	    spdk_json_decode_object_relaxed(opts->transport_specific, tcp_transport_opts_decoder,
622 					    SPDK_COUNTOF(tcp_transport_opts_decoder),
623 					    &ttransport->tcp_opts)) {
624 		SPDK_ERRLOG("spdk_json_decode_object_relaxed failed\n");
625 		free(ttransport);
626 		return NULL;
627 	}
628 
629 	SPDK_NOTICELOG("*** TCP Transport Init ***\n");
630 
631 	SPDK_INFOLOG(nvmf_tcp, "*** TCP Transport Init ***\n"
632 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
633 		     "  max_io_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
634 		     "  in_capsule_data_size=%d, max_aq_depth=%d\n"
635 		     "  num_shared_buffers=%d, c2h_success=%d,\n"
636 		     "  dif_insert_or_strip=%d, sock_priority=%d\n"
637 		     "  abort_timeout_sec=%d, control_msg_num=%hu\n",
638 		     opts->max_queue_depth,
639 		     opts->max_io_size,
640 		     opts->max_qpairs_per_ctrlr - 1,
641 		     opts->io_unit_size,
642 		     opts->in_capsule_data_size,
643 		     opts->max_aq_depth,
644 		     opts->num_shared_buffers,
645 		     ttransport->tcp_opts.c2h_success,
646 		     opts->dif_insert_or_strip,
647 		     ttransport->tcp_opts.sock_priority,
648 		     opts->abort_timeout_sec,
649 		     ttransport->tcp_opts.control_msg_num);
650 
651 	if (ttransport->tcp_opts.sock_priority > SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY) {
652 		SPDK_ERRLOG("Unsupported socket_priority=%d, the current range is: 0 to %d\n"
653 			    "you can use man 7 socket to view the range of priority under SO_PRIORITY item\n",
654 			    ttransport->tcp_opts.sock_priority, SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY);
655 		free(ttransport);
656 		return NULL;
657 	}
658 
659 	if (ttransport->tcp_opts.control_msg_num == 0 &&
660 	    opts->in_capsule_data_size < SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE) {
661 		SPDK_WARNLOG("TCP param control_msg_num can't be 0 if ICD is less than %u bytes. Using default value %u\n",
662 			     SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE, SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM);
663 		ttransport->tcp_opts.control_msg_num = SPDK_NVMF_TCP_DEFAULT_CONTROL_MSG_NUM;
664 	}
665 
666 	/* I/O unit size cannot be larger than max I/O size */
667 	if (opts->io_unit_size > opts->max_io_size) {
668 		SPDK_WARNLOG("TCP param io_unit_size %u can't be larger than max_io_size %u. Using max_io_size as io_unit_size\n",
669 			     opts->io_unit_size, opts->max_io_size);
670 		opts->io_unit_size = opts->max_io_size;
671 	}
672 
673 	/* In capsule data size cannot be larger than max I/O size */
674 	if (opts->in_capsule_data_size > opts->max_io_size) {
675 		SPDK_WARNLOG("TCP param ICD size %u can't be larger than max_io_size %u. Using max_io_size as ICD size\n",
676 			     opts->io_unit_size, opts->max_io_size);
677 		opts->in_capsule_data_size = opts->max_io_size;
678 	}
679 
680 	/* max IO queue depth cannot be smaller than 2 or larger than 65535.
681 	 * We will not check SPDK_NVMF_TCP_MAX_IO_QUEUE_DEPTH, because max_queue_depth is 16bits and always not larger than 64k. */
682 	if (opts->max_queue_depth < SPDK_NVMF_TCP_MIN_IO_QUEUE_DEPTH) {
683 		SPDK_WARNLOG("TCP param max_queue_depth %u can't be smaller than %u or larger than %u. Using default value %u\n",
684 			     opts->max_queue_depth, SPDK_NVMF_TCP_MIN_IO_QUEUE_DEPTH,
685 			     SPDK_NVMF_TCP_MAX_IO_QUEUE_DEPTH, SPDK_NVMF_TCP_DEFAULT_MAX_IO_QUEUE_DEPTH);
686 		opts->max_queue_depth = SPDK_NVMF_TCP_DEFAULT_MAX_IO_QUEUE_DEPTH;
687 	}
688 
689 	/* max admin queue depth cannot be smaller than 2 or larger than 4096 */
690 	if (opts->max_aq_depth < SPDK_NVMF_TCP_MIN_ADMIN_QUEUE_DEPTH ||
691 	    opts->max_aq_depth > SPDK_NVMF_TCP_MAX_ADMIN_QUEUE_DEPTH) {
692 		SPDK_WARNLOG("TCP param max_aq_depth %u can't be smaller than %u or larger than %u. Using default value %u\n",
693 			     opts->max_aq_depth, SPDK_NVMF_TCP_MIN_ADMIN_QUEUE_DEPTH,
694 			     SPDK_NVMF_TCP_MAX_ADMIN_QUEUE_DEPTH, SPDK_NVMF_TCP_DEFAULT_MAX_ADMIN_QUEUE_DEPTH);
695 		opts->max_aq_depth = SPDK_NVMF_TCP_DEFAULT_MAX_ADMIN_QUEUE_DEPTH;
696 	}
697 
698 	sge_count = opts->max_io_size / opts->io_unit_size;
699 	if (sge_count > SPDK_NVMF_MAX_SGL_ENTRIES) {
700 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
701 		free(ttransport);
702 		return NULL;
703 	}
704 
705 	/* If buf_cache_size == UINT32_MAX, we will dynamically pick a cache size later that we know will fit. */
706 	if (opts->buf_cache_size < UINT32_MAX) {
707 		min_shared_buffers = spdk_env_get_core_count() * opts->buf_cache_size;
708 		if (min_shared_buffers > opts->num_shared_buffers) {
709 			SPDK_ERRLOG("There are not enough buffers to satisfy "
710 				    "per-poll group caches for each thread. (%" PRIu32 ") "
711 				    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
712 			SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
713 			free(ttransport);
714 			return NULL;
715 		}
716 	}
717 
718 	ttransport->accept_poller = SPDK_POLLER_REGISTER(nvmf_tcp_accept, &ttransport->transport,
719 				    opts->acceptor_poll_rate);
720 	if (!ttransport->accept_poller) {
721 		free(ttransport);
722 		return NULL;
723 	}
724 
725 	return &ttransport->transport;
726 }
727 
728 static int
729 nvmf_tcp_trsvcid_to_int(const char *trsvcid)
730 {
731 	unsigned long long ull;
732 	char *end = NULL;
733 
734 	ull = strtoull(trsvcid, &end, 10);
735 	if (end == NULL || end == trsvcid || *end != '\0') {
736 		return -1;
737 	}
738 
739 	/* Valid TCP/IP port numbers are in [0, 65535] */
740 	if (ull > 65535) {
741 		return -1;
742 	}
743 
744 	return (int)ull;
745 }
746 
747 /**
748  * Canonicalize a listen address trid.
749  */
750 static int
751 nvmf_tcp_canon_listen_trid(struct spdk_nvme_transport_id *canon_trid,
752 			   const struct spdk_nvme_transport_id *trid)
753 {
754 	int trsvcid_int;
755 
756 	trsvcid_int = nvmf_tcp_trsvcid_to_int(trid->trsvcid);
757 	if (trsvcid_int < 0) {
758 		return -EINVAL;
759 	}
760 
761 	memset(canon_trid, 0, sizeof(*canon_trid));
762 	spdk_nvme_trid_populate_transport(canon_trid, SPDK_NVME_TRANSPORT_TCP);
763 	canon_trid->adrfam = trid->adrfam;
764 	snprintf(canon_trid->traddr, sizeof(canon_trid->traddr), "%s", trid->traddr);
765 	snprintf(canon_trid->trsvcid, sizeof(canon_trid->trsvcid), "%d", trsvcid_int);
766 
767 	return 0;
768 }
769 
770 /**
771  * Find an existing listening port.
772  */
773 static struct spdk_nvmf_tcp_port *
774 nvmf_tcp_find_port(struct spdk_nvmf_tcp_transport *ttransport,
775 		   const struct spdk_nvme_transport_id *trid)
776 {
777 	struct spdk_nvme_transport_id canon_trid;
778 	struct spdk_nvmf_tcp_port *port;
779 
780 	if (nvmf_tcp_canon_listen_trid(&canon_trid, trid) != 0) {
781 		return NULL;
782 	}
783 
784 	TAILQ_FOREACH(port, &ttransport->ports, link) {
785 		if (spdk_nvme_transport_id_compare(&canon_trid, port->trid) == 0) {
786 			return port;
787 		}
788 	}
789 
790 	return NULL;
791 }
792 
793 static int
794 nvmf_tcp_listen(struct spdk_nvmf_transport *transport, const struct spdk_nvme_transport_id *trid,
795 		struct spdk_nvmf_listen_opts *listen_opts)
796 {
797 	struct spdk_nvmf_tcp_transport *ttransport;
798 	struct spdk_nvmf_tcp_port *port;
799 	int trsvcid_int;
800 	uint8_t adrfam;
801 	struct spdk_sock_opts opts;
802 
803 	if (!strlen(trid->trsvcid)) {
804 		SPDK_ERRLOG("Service id is required\n");
805 		return -EINVAL;
806 	}
807 
808 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
809 
810 	trsvcid_int = nvmf_tcp_trsvcid_to_int(trid->trsvcid);
811 	if (trsvcid_int < 0) {
812 		SPDK_ERRLOG("Invalid trsvcid '%s'\n", trid->trsvcid);
813 		return -EINVAL;
814 	}
815 
816 	port = calloc(1, sizeof(*port));
817 	if (!port) {
818 		SPDK_ERRLOG("Port allocation failed\n");
819 		return -ENOMEM;
820 	}
821 
822 	port->trid = trid;
823 	opts.opts_size = sizeof(opts);
824 	spdk_sock_get_default_opts(&opts);
825 	opts.priority = ttransport->tcp_opts.sock_priority;
826 	/* TODO: also add impl_opts like on the initiator side */
827 	port->listen_sock = spdk_sock_listen_ext(trid->traddr, trsvcid_int,
828 			    NULL, &opts);
829 	if (port->listen_sock == NULL) {
830 		SPDK_ERRLOG("spdk_sock_listen(%s, %d) failed: %s (%d)\n",
831 			    trid->traddr, trsvcid_int,
832 			    spdk_strerror(errno), errno);
833 		free(port);
834 		return -errno;
835 	}
836 
837 	if (spdk_sock_is_ipv4(port->listen_sock)) {
838 		adrfam = SPDK_NVMF_ADRFAM_IPV4;
839 	} else if (spdk_sock_is_ipv6(port->listen_sock)) {
840 		adrfam = SPDK_NVMF_ADRFAM_IPV6;
841 	} else {
842 		SPDK_ERRLOG("Unhandled socket type\n");
843 		adrfam = 0;
844 	}
845 
846 	if (adrfam != trid->adrfam) {
847 		SPDK_ERRLOG("Socket address family mismatch\n");
848 		spdk_sock_close(&port->listen_sock);
849 		free(port);
850 		return -EINVAL;
851 	}
852 
853 	SPDK_NOTICELOG("*** NVMe/TCP Target Listening on %s port %s ***\n",
854 		       trid->traddr, trid->trsvcid);
855 
856 	TAILQ_INSERT_TAIL(&ttransport->ports, port, link);
857 	return 0;
858 }
859 
860 static void
861 nvmf_tcp_stop_listen(struct spdk_nvmf_transport *transport,
862 		     const struct spdk_nvme_transport_id *trid)
863 {
864 	struct spdk_nvmf_tcp_transport *ttransport;
865 	struct spdk_nvmf_tcp_port *port;
866 
867 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
868 
869 	SPDK_DEBUGLOG(nvmf_tcp, "Removing listen address %s port %s\n",
870 		      trid->traddr, trid->trsvcid);
871 
872 	port = nvmf_tcp_find_port(ttransport, trid);
873 	if (port) {
874 		TAILQ_REMOVE(&ttransport->ports, port, link);
875 		spdk_sock_close(&port->listen_sock);
876 		free(port);
877 	}
878 }
879 
880 static void nvmf_tcp_qpair_set_recv_state(struct spdk_nvmf_tcp_qpair *tqpair,
881 		enum nvme_tcp_pdu_recv_state state);
882 
883 static void
884 nvmf_tcp_qpair_set_state(struct spdk_nvmf_tcp_qpair *tqpair, enum nvme_tcp_qpair_state state)
885 {
886 	tqpair->state = state;
887 	spdk_trace_record(TRACE_TCP_QP_STATE_CHANGE, tqpair->qpair.qid, 0, (uintptr_t)tqpair,
888 			  tqpair->state);
889 }
890 
891 static void
892 nvmf_tcp_qpair_disconnect(struct spdk_nvmf_tcp_qpair *tqpair)
893 {
894 	SPDK_DEBUGLOG(nvmf_tcp, "Disconnecting qpair %p\n", tqpair);
895 
896 	spdk_trace_record(TRACE_TCP_QP_DISCONNECT, 0, 0, (uintptr_t)tqpair);
897 
898 	if (tqpair->state <= NVME_TCP_QPAIR_STATE_RUNNING) {
899 		nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_EXITING);
900 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
901 		spdk_poller_unregister(&tqpair->timeout_poller);
902 
903 		/* This will end up calling nvmf_tcp_close_qpair */
904 		spdk_nvmf_qpair_disconnect(&tqpair->qpair, NULL, NULL);
905 	}
906 }
907 
908 static void
909 _mgmt_pdu_write_done(void *_tqpair, int err)
910 {
911 	struct spdk_nvmf_tcp_qpair *tqpair = _tqpair;
912 	struct nvme_tcp_pdu *pdu = tqpair->mgmt_pdu;
913 
914 	if (spdk_unlikely(err != 0)) {
915 		nvmf_tcp_qpair_disconnect(tqpair);
916 		return;
917 	}
918 
919 	assert(pdu->cb_fn != NULL);
920 	pdu->cb_fn(pdu->cb_arg);
921 }
922 
923 static void
924 _req_pdu_write_done(void *req, int err)
925 {
926 	struct spdk_nvmf_tcp_req *tcp_req = req;
927 	struct nvme_tcp_pdu *pdu = tcp_req->pdu;
928 	struct spdk_nvmf_tcp_qpair *tqpair = pdu->qpair;
929 
930 	assert(tcp_req->pdu_in_use);
931 	tcp_req->pdu_in_use = false;
932 
933 	/* If the request is in a completed state, we're waiting for write completion to free it */
934 	if (spdk_unlikely(tcp_req->state == TCP_REQUEST_STATE_COMPLETED)) {
935 		nvmf_tcp_request_free(tcp_req);
936 		return;
937 	}
938 
939 	if (spdk_unlikely(err != 0)) {
940 		nvmf_tcp_qpair_disconnect(tqpair);
941 		return;
942 	}
943 
944 	assert(pdu->cb_fn != NULL);
945 	pdu->cb_fn(pdu->cb_arg);
946 }
947 
948 static void
949 _pdu_write_done(struct nvme_tcp_pdu *pdu, int err)
950 {
951 	pdu->sock_req.cb_fn(pdu->sock_req.cb_arg, err);
952 }
953 
954 static void
955 _tcp_write_pdu(struct nvme_tcp_pdu *pdu)
956 {
957 	int rc;
958 	uint32_t mapped_length;
959 	struct spdk_nvmf_tcp_qpair *tqpair = pdu->qpair;
960 
961 	pdu->sock_req.iovcnt = nvme_tcp_build_iovs(pdu->iov, SPDK_COUNTOF(pdu->iov), pdu,
962 			       tqpair->host_hdgst_enable, tqpair->host_ddgst_enable, &mapped_length);
963 	spdk_sock_writev_async(tqpair->sock, &pdu->sock_req);
964 
965 	if (pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_RESP ||
966 	    pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ) {
967 		/* Try to force the send immediately. */
968 		rc = spdk_sock_flush(tqpair->sock);
969 		if (rc > 0 && (uint32_t)rc == mapped_length) {
970 			_pdu_write_done(pdu, 0);
971 		} else {
972 			SPDK_ERRLOG("Could not write %s to socket: rc=%d, errno=%d\n",
973 				    pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_RESP ?
974 				    "IC_RESP" : "TERM_REQ", rc, errno);
975 			_pdu_write_done(pdu, rc >= 0 ? -EAGAIN : -errno);
976 		}
977 	}
978 }
979 
980 static void
981 data_crc32_accel_done(void *cb_arg, int status)
982 {
983 	struct nvme_tcp_pdu *pdu = cb_arg;
984 
985 	if (spdk_unlikely(status)) {
986 		SPDK_ERRLOG("Failed to compute the data digest for pdu =%p\n", pdu);
987 		_pdu_write_done(pdu, status);
988 		return;
989 	}
990 
991 	pdu->data_digest_crc32 ^= SPDK_CRC32C_XOR;
992 	MAKE_DIGEST_WORD(pdu->data_digest, pdu->data_digest_crc32);
993 
994 	_tcp_write_pdu(pdu);
995 }
996 
997 static void
998 pdu_data_crc32_compute(struct nvme_tcp_pdu *pdu)
999 {
1000 	struct spdk_nvmf_tcp_qpair *tqpair = pdu->qpair;
1001 	int rc = 0;
1002 
1003 	/* Data Digest */
1004 	if (pdu->data_len > 0 && g_nvme_tcp_ddgst[pdu->hdr.common.pdu_type] && tqpair->host_ddgst_enable) {
1005 		/* Only support this limitated case for the first step */
1006 		if (spdk_likely(!pdu->dif_ctx && (pdu->data_len % SPDK_NVME_TCP_DIGEST_ALIGNMENT == 0)
1007 				&& tqpair->group)) {
1008 			rc = spdk_accel_submit_crc32cv(tqpair->group->accel_channel, &pdu->data_digest_crc32, pdu->data_iov,
1009 						       pdu->data_iovcnt, 0, data_crc32_accel_done, pdu);
1010 			if (spdk_likely(rc == 0)) {
1011 				return;
1012 			}
1013 		} else {
1014 			pdu->data_digest_crc32 = nvme_tcp_pdu_calc_data_digest(pdu);
1015 		}
1016 		data_crc32_accel_done(pdu, rc);
1017 	} else {
1018 		_tcp_write_pdu(pdu);
1019 	}
1020 }
1021 
1022 static void
1023 nvmf_tcp_qpair_write_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
1024 			 struct nvme_tcp_pdu *pdu,
1025 			 nvme_tcp_qpair_xfer_complete_cb cb_fn,
1026 			 void *cb_arg)
1027 {
1028 	int hlen;
1029 	uint32_t crc32c;
1030 
1031 	assert(tqpair->pdu_in_progress != pdu);
1032 
1033 	hlen = pdu->hdr.common.hlen;
1034 	pdu->cb_fn = cb_fn;
1035 	pdu->cb_arg = cb_arg;
1036 
1037 	pdu->iov[0].iov_base = &pdu->hdr.raw;
1038 	pdu->iov[0].iov_len = hlen;
1039 
1040 	/* Header Digest */
1041 	if (g_nvme_tcp_hdgst[pdu->hdr.common.pdu_type] && tqpair->host_hdgst_enable) {
1042 		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
1043 		MAKE_DIGEST_WORD((uint8_t *)pdu->hdr.raw + hlen, crc32c);
1044 	}
1045 
1046 	/* Data Digest */
1047 	pdu_data_crc32_compute(pdu);
1048 }
1049 
1050 static void
1051 nvmf_tcp_qpair_write_mgmt_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
1052 			      nvme_tcp_qpair_xfer_complete_cb cb_fn,
1053 			      void *cb_arg)
1054 {
1055 	struct nvme_tcp_pdu *pdu = tqpair->mgmt_pdu;
1056 
1057 	pdu->sock_req.cb_fn = _mgmt_pdu_write_done;
1058 	pdu->sock_req.cb_arg = tqpair;
1059 
1060 	nvmf_tcp_qpair_write_pdu(tqpair, pdu, cb_fn, cb_arg);
1061 }
1062 
1063 static void
1064 nvmf_tcp_qpair_write_req_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
1065 			     struct spdk_nvmf_tcp_req *tcp_req,
1066 			     nvme_tcp_qpair_xfer_complete_cb cb_fn,
1067 			     void *cb_arg)
1068 {
1069 	struct nvme_tcp_pdu *pdu = tcp_req->pdu;
1070 
1071 	pdu->sock_req.cb_fn = _req_pdu_write_done;
1072 	pdu->sock_req.cb_arg = tcp_req;
1073 
1074 	assert(!tcp_req->pdu_in_use);
1075 	tcp_req->pdu_in_use = true;
1076 
1077 	nvmf_tcp_qpair_write_pdu(tqpair, pdu, cb_fn, cb_arg);
1078 }
1079 
1080 static int
1081 nvmf_tcp_qpair_init_mem_resource(struct spdk_nvmf_tcp_qpair *tqpair)
1082 {
1083 	uint32_t i;
1084 	struct spdk_nvmf_transport_opts *opts;
1085 	uint32_t in_capsule_data_size;
1086 
1087 	opts = &tqpair->qpair.transport->opts;
1088 
1089 	in_capsule_data_size = opts->in_capsule_data_size;
1090 	if (opts->dif_insert_or_strip) {
1091 		in_capsule_data_size = SPDK_BDEV_BUF_SIZE_WITH_MD(in_capsule_data_size);
1092 	}
1093 
1094 	tqpair->resource_count = opts->max_queue_depth;
1095 
1096 	tqpair->reqs = calloc(tqpair->resource_count, sizeof(*tqpair->reqs));
1097 	if (!tqpair->reqs) {
1098 		SPDK_ERRLOG("Unable to allocate reqs on tqpair=%p\n", tqpair);
1099 		return -1;
1100 	}
1101 
1102 	if (in_capsule_data_size) {
1103 		tqpair->bufs = spdk_zmalloc(tqpair->resource_count * in_capsule_data_size, 0x1000,
1104 					    NULL, SPDK_ENV_LCORE_ID_ANY,
1105 					    SPDK_MALLOC_DMA);
1106 		if (!tqpair->bufs) {
1107 			SPDK_ERRLOG("Unable to allocate bufs on tqpair=%p.\n", tqpair);
1108 			return -1;
1109 		}
1110 	}
1111 	/* prepare memory space for receiving pdus and tcp_req */
1112 	/* Add additional 1 member, which will be used for mgmt_pdu owned by the tqpair */
1113 	tqpair->pdus = spdk_dma_zmalloc((2 * tqpair->resource_count + 1) * sizeof(*tqpair->pdus), 0x1000,
1114 					NULL);
1115 	if (!tqpair->pdus) {
1116 		SPDK_ERRLOG("Unable to allocate pdu pool on tqpair =%p.\n", tqpair);
1117 		return -1;
1118 	}
1119 
1120 	for (i = 0; i < tqpair->resource_count; i++) {
1121 		struct spdk_nvmf_tcp_req *tcp_req = &tqpair->reqs[i];
1122 
1123 		tcp_req->ttag = i + 1;
1124 		tcp_req->req.qpair = &tqpair->qpair;
1125 
1126 		tcp_req->pdu = &tqpair->pdus[i];
1127 		tcp_req->pdu->qpair = tqpair;
1128 
1129 		/* Set up memory to receive commands */
1130 		if (tqpair->bufs) {
1131 			tcp_req->buf = (void *)((uintptr_t)tqpair->bufs + (i * in_capsule_data_size));
1132 		}
1133 
1134 		/* Set the cmdn and rsp */
1135 		tcp_req->req.rsp = (union nvmf_c2h_msg *)&tcp_req->rsp;
1136 		tcp_req->req.cmd = (union nvmf_h2c_msg *)&tcp_req->cmd;
1137 
1138 		tcp_req->req.stripped_data = NULL;
1139 
1140 		/* Initialize request state to FREE */
1141 		tcp_req->state = TCP_REQUEST_STATE_FREE;
1142 		TAILQ_INSERT_TAIL(&tqpair->tcp_req_free_queue, tcp_req, state_link);
1143 		tqpair->state_cntr[TCP_REQUEST_STATE_FREE]++;
1144 	}
1145 
1146 	for (; i < 2 * tqpair->resource_count; i++) {
1147 		struct nvme_tcp_pdu *pdu = &tqpair->pdus[i];
1148 
1149 		pdu->qpair = tqpair;
1150 		SLIST_INSERT_HEAD(&tqpair->tcp_pdu_free_queue, pdu, slist);
1151 	}
1152 
1153 	tqpair->mgmt_pdu = &tqpair->pdus[i];
1154 	tqpair->mgmt_pdu->qpair = tqpair;
1155 	tqpair->pdu_in_progress = SLIST_FIRST(&tqpair->tcp_pdu_free_queue);
1156 	SLIST_REMOVE_HEAD(&tqpair->tcp_pdu_free_queue, slist);
1157 
1158 	tqpair->recv_buf_size = (in_capsule_data_size + sizeof(struct spdk_nvme_tcp_cmd) + 2 *
1159 				 SPDK_NVME_TCP_DIGEST_LEN) * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
1160 
1161 	return 0;
1162 }
1163 
1164 static int
1165 nvmf_tcp_qpair_init(struct spdk_nvmf_qpair *qpair)
1166 {
1167 	struct spdk_nvmf_tcp_qpair *tqpair;
1168 
1169 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
1170 
1171 	SPDK_DEBUGLOG(nvmf_tcp, "New TCP Connection: %p\n", qpair);
1172 
1173 	spdk_trace_record(TRACE_TCP_QP_CREATE, 0, 0, (uintptr_t)tqpair);
1174 
1175 	/* Initialise request state queues of the qpair */
1176 	TAILQ_INIT(&tqpair->tcp_req_free_queue);
1177 	TAILQ_INIT(&tqpair->tcp_req_working_queue);
1178 	SLIST_INIT(&tqpair->tcp_pdu_free_queue);
1179 
1180 	tqpair->host_hdgst_enable = true;
1181 	tqpair->host_ddgst_enable = true;
1182 
1183 	return 0;
1184 }
1185 
1186 static int
1187 nvmf_tcp_qpair_sock_init(struct spdk_nvmf_tcp_qpair *tqpair)
1188 {
1189 	int rc;
1190 
1191 	spdk_trace_record(TRACE_TCP_QP_SOCK_INIT, 0, 0, (uintptr_t)tqpair);
1192 
1193 	/* set low water mark */
1194 	rc = spdk_sock_set_recvlowat(tqpair->sock, 1);
1195 	if (rc != 0) {
1196 		SPDK_ERRLOG("spdk_sock_set_recvlowat() failed\n");
1197 		return rc;
1198 	}
1199 
1200 	return 0;
1201 }
1202 
1203 static void
1204 nvmf_tcp_handle_connect(struct spdk_nvmf_transport *transport,
1205 			struct spdk_nvmf_tcp_port *port,
1206 			struct spdk_sock *sock)
1207 {
1208 	struct spdk_nvmf_tcp_qpair *tqpair;
1209 	int rc;
1210 
1211 	SPDK_DEBUGLOG(nvmf_tcp, "New connection accepted on %s port %s\n",
1212 		      port->trid->traddr, port->trid->trsvcid);
1213 
1214 	tqpair = calloc(1, sizeof(struct spdk_nvmf_tcp_qpair));
1215 	if (tqpair == NULL) {
1216 		SPDK_ERRLOG("Could not allocate new connection.\n");
1217 		spdk_sock_close(&sock);
1218 		return;
1219 	}
1220 
1221 	tqpair->sock = sock;
1222 	tqpair->state_cntr[TCP_REQUEST_STATE_FREE] = 0;
1223 	tqpair->port = port;
1224 	tqpair->qpair.transport = transport;
1225 
1226 	rc = spdk_sock_getaddr(tqpair->sock, tqpair->target_addr,
1227 			       sizeof(tqpair->target_addr), &tqpair->target_port,
1228 			       tqpair->initiator_addr, sizeof(tqpair->initiator_addr),
1229 			       &tqpair->initiator_port);
1230 	if (rc < 0) {
1231 		SPDK_ERRLOG("spdk_sock_getaddr() failed of tqpair=%p\n", tqpair);
1232 		nvmf_tcp_qpair_destroy(tqpair);
1233 		return;
1234 	}
1235 
1236 	spdk_nvmf_tgt_new_qpair(transport->tgt, &tqpair->qpair);
1237 }
1238 
1239 static uint32_t
1240 nvmf_tcp_port_accept(struct spdk_nvmf_transport *transport, struct spdk_nvmf_tcp_port *port)
1241 {
1242 	struct spdk_sock *sock;
1243 	uint32_t count = 0;
1244 	int i;
1245 
1246 	for (i = 0; i < NVMF_TCP_MAX_ACCEPT_SOCK_ONE_TIME; i++) {
1247 		sock = spdk_sock_accept(port->listen_sock);
1248 		if (sock == NULL) {
1249 			break;
1250 		}
1251 		count++;
1252 		nvmf_tcp_handle_connect(transport, port, sock);
1253 	}
1254 
1255 	return count;
1256 }
1257 
1258 static int
1259 nvmf_tcp_accept(void *ctx)
1260 {
1261 	struct spdk_nvmf_transport *transport = ctx;
1262 	struct spdk_nvmf_tcp_transport *ttransport;
1263 	struct spdk_nvmf_tcp_port *port;
1264 	uint32_t count = 0;
1265 
1266 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
1267 
1268 	TAILQ_FOREACH(port, &ttransport->ports, link) {
1269 		count += nvmf_tcp_port_accept(transport, port);
1270 	}
1271 
1272 	return count > 0 ? SPDK_POLLER_BUSY : SPDK_POLLER_IDLE;
1273 }
1274 
1275 static void
1276 nvmf_tcp_discover(struct spdk_nvmf_transport *transport,
1277 		  struct spdk_nvme_transport_id *trid,
1278 		  struct spdk_nvmf_discovery_log_page_entry *entry)
1279 {
1280 	entry->trtype = SPDK_NVMF_TRTYPE_TCP;
1281 	entry->adrfam = trid->adrfam;
1282 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
1283 
1284 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
1285 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
1286 
1287 	entry->tsas.tcp.sectype = SPDK_NVME_TCP_SECURITY_NONE;
1288 }
1289 
1290 static struct spdk_nvmf_tcp_control_msg_list *
1291 nvmf_tcp_control_msg_list_create(uint16_t num_messages)
1292 {
1293 	struct spdk_nvmf_tcp_control_msg_list *list;
1294 	struct spdk_nvmf_tcp_control_msg *msg;
1295 	uint16_t i;
1296 
1297 	list = calloc(1, sizeof(*list));
1298 	if (!list) {
1299 		SPDK_ERRLOG("Failed to allocate memory for list structure\n");
1300 		return NULL;
1301 	}
1302 
1303 	list->msg_buf = spdk_zmalloc(num_messages * SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE,
1304 				     NVMF_DATA_BUFFER_ALIGNMENT, NULL, SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
1305 	if (!list->msg_buf) {
1306 		SPDK_ERRLOG("Failed to allocate memory for control message buffers\n");
1307 		free(list);
1308 		return NULL;
1309 	}
1310 
1311 	STAILQ_INIT(&list->free_msgs);
1312 
1313 	for (i = 0; i < num_messages; i++) {
1314 		msg = (struct spdk_nvmf_tcp_control_msg *)((char *)list->msg_buf + i *
1315 				SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE);
1316 		STAILQ_INSERT_TAIL(&list->free_msgs, msg, link);
1317 	}
1318 
1319 	return list;
1320 }
1321 
1322 static void
1323 nvmf_tcp_control_msg_list_free(struct spdk_nvmf_tcp_control_msg_list *list)
1324 {
1325 	if (!list) {
1326 		return;
1327 	}
1328 
1329 	spdk_free(list->msg_buf);
1330 	free(list);
1331 }
1332 
1333 static struct spdk_nvmf_transport_poll_group *
1334 nvmf_tcp_poll_group_create(struct spdk_nvmf_transport *transport,
1335 			   struct spdk_nvmf_poll_group *group)
1336 {
1337 	struct spdk_nvmf_tcp_transport	*ttransport;
1338 	struct spdk_nvmf_tcp_poll_group *tgroup;
1339 
1340 	tgroup = calloc(1, sizeof(*tgroup));
1341 	if (!tgroup) {
1342 		return NULL;
1343 	}
1344 
1345 	tgroup->sock_group = spdk_sock_group_create(&tgroup->group);
1346 	if (!tgroup->sock_group) {
1347 		goto cleanup;
1348 	}
1349 
1350 	TAILQ_INIT(&tgroup->qpairs);
1351 	TAILQ_INIT(&tgroup->await_req);
1352 
1353 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
1354 
1355 	if (transport->opts.in_capsule_data_size < SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE) {
1356 		SPDK_DEBUGLOG(nvmf_tcp, "ICD %u is less than min required for admin/fabric commands (%u). "
1357 			      "Creating control messages list\n", transport->opts.in_capsule_data_size,
1358 			      SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE);
1359 		tgroup->control_msg_list = nvmf_tcp_control_msg_list_create(ttransport->tcp_opts.control_msg_num);
1360 		if (!tgroup->control_msg_list) {
1361 			goto cleanup;
1362 		}
1363 	}
1364 
1365 	tgroup->accel_channel = spdk_accel_get_io_channel();
1366 	if (spdk_unlikely(!tgroup->accel_channel)) {
1367 		SPDK_ERRLOG("Cannot create accel_channel for tgroup=%p\n", tgroup);
1368 		goto cleanup;
1369 	}
1370 
1371 	TAILQ_INSERT_TAIL(&ttransport->poll_groups, tgroup, link);
1372 	if (ttransport->next_pg == NULL) {
1373 		ttransport->next_pg = tgroup;
1374 	}
1375 
1376 	return &tgroup->group;
1377 
1378 cleanup:
1379 	nvmf_tcp_poll_group_destroy(&tgroup->group);
1380 	return NULL;
1381 }
1382 
1383 static struct spdk_nvmf_transport_poll_group *
1384 nvmf_tcp_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
1385 {
1386 	struct spdk_nvmf_tcp_transport *ttransport;
1387 	struct spdk_nvmf_tcp_poll_group **pg;
1388 	struct spdk_nvmf_tcp_qpair *tqpair;
1389 	struct spdk_sock_group *group = NULL, *hint = NULL;
1390 	int rc;
1391 
1392 	ttransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_tcp_transport, transport);
1393 
1394 	if (TAILQ_EMPTY(&ttransport->poll_groups)) {
1395 		return NULL;
1396 	}
1397 
1398 	pg = &ttransport->next_pg;
1399 	assert(*pg != NULL);
1400 	hint = (*pg)->sock_group;
1401 
1402 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
1403 	rc = spdk_sock_get_optimal_sock_group(tqpair->sock, &group, hint);
1404 	if (rc != 0) {
1405 		return NULL;
1406 	} else if (group != NULL) {
1407 		/* Optimal poll group was found */
1408 		return spdk_sock_group_get_ctx(group);
1409 	}
1410 
1411 	/* The hint was used for optimal poll group, advance next_pg. */
1412 	*pg = TAILQ_NEXT(*pg, link);
1413 	if (*pg == NULL) {
1414 		*pg = TAILQ_FIRST(&ttransport->poll_groups);
1415 	}
1416 
1417 	return spdk_sock_group_get_ctx(hint);
1418 }
1419 
1420 static void
1421 nvmf_tcp_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
1422 {
1423 	struct spdk_nvmf_tcp_poll_group *tgroup, *next_tgroup;
1424 	struct spdk_nvmf_tcp_transport *ttransport;
1425 
1426 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
1427 	spdk_sock_group_close(&tgroup->sock_group);
1428 	if (tgroup->control_msg_list) {
1429 		nvmf_tcp_control_msg_list_free(tgroup->control_msg_list);
1430 	}
1431 
1432 	if (tgroup->accel_channel) {
1433 		spdk_put_io_channel(tgroup->accel_channel);
1434 	}
1435 
1436 	ttransport = SPDK_CONTAINEROF(tgroup->group.transport, struct spdk_nvmf_tcp_transport, transport);
1437 
1438 	next_tgroup = TAILQ_NEXT(tgroup, link);
1439 	TAILQ_REMOVE(&ttransport->poll_groups, tgroup, link);
1440 	if (next_tgroup == NULL) {
1441 		next_tgroup = TAILQ_FIRST(&ttransport->poll_groups);
1442 	}
1443 	if (ttransport->next_pg == tgroup) {
1444 		ttransport->next_pg = next_tgroup;
1445 	}
1446 
1447 	free(tgroup);
1448 }
1449 
1450 static void
1451 nvmf_tcp_qpair_set_recv_state(struct spdk_nvmf_tcp_qpair *tqpair,
1452 			      enum nvme_tcp_pdu_recv_state state)
1453 {
1454 	if (tqpair->recv_state == state) {
1455 		SPDK_ERRLOG("The recv state of tqpair=%p is same with the state(%d) to be set\n",
1456 			    tqpair, state);
1457 		return;
1458 	}
1459 
1460 	if (tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_REQ) {
1461 		/* When leaving the await req state, move the qpair to the main list */
1462 		TAILQ_REMOVE(&tqpair->group->await_req, tqpair, link);
1463 		TAILQ_INSERT_TAIL(&tqpair->group->qpairs, tqpair, link);
1464 	} else if (state == NVME_TCP_PDU_RECV_STATE_AWAIT_REQ) {
1465 		TAILQ_REMOVE(&tqpair->group->qpairs, tqpair, link);
1466 		TAILQ_INSERT_TAIL(&tqpair->group->await_req, tqpair, link);
1467 	}
1468 
1469 	SPDK_DEBUGLOG(nvmf_tcp, "tqpair(%p) recv state=%d\n", tqpair, state);
1470 	tqpair->recv_state = state;
1471 
1472 	spdk_trace_record(TRACE_TCP_QP_RCV_STATE_CHANGE, tqpair->qpair.qid, 0, (uintptr_t)tqpair,
1473 			  tqpair->recv_state);
1474 }
1475 
1476 static int
1477 nvmf_tcp_qpair_handle_timeout(void *ctx)
1478 {
1479 	struct spdk_nvmf_tcp_qpair *tqpair = ctx;
1480 
1481 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_ERROR);
1482 
1483 	SPDK_ERRLOG("No pdu coming for tqpair=%p within %d seconds\n", tqpair,
1484 		    SPDK_NVME_TCP_QPAIR_EXIT_TIMEOUT);
1485 
1486 	nvmf_tcp_qpair_disconnect(tqpair);
1487 	return SPDK_POLLER_BUSY;
1488 }
1489 
1490 static void
1491 nvmf_tcp_send_c2h_term_req_complete(void *cb_arg)
1492 {
1493 	struct spdk_nvmf_tcp_qpair *tqpair = (struct spdk_nvmf_tcp_qpair *)cb_arg;
1494 
1495 	if (!tqpair->timeout_poller) {
1496 		tqpair->timeout_poller = SPDK_POLLER_REGISTER(nvmf_tcp_qpair_handle_timeout, tqpair,
1497 					 SPDK_NVME_TCP_QPAIR_EXIT_TIMEOUT * 1000000);
1498 	}
1499 }
1500 
1501 static void
1502 nvmf_tcp_send_c2h_term_req(struct spdk_nvmf_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu,
1503 			   enum spdk_nvme_tcp_term_req_fes fes, uint32_t error_offset)
1504 {
1505 	struct nvme_tcp_pdu *rsp_pdu;
1506 	struct spdk_nvme_tcp_term_req_hdr *c2h_term_req;
1507 	uint32_t c2h_term_req_hdr_len = sizeof(*c2h_term_req);
1508 	uint32_t copy_len;
1509 
1510 	rsp_pdu = tqpair->mgmt_pdu;
1511 
1512 	c2h_term_req = &rsp_pdu->hdr.term_req;
1513 	c2h_term_req->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ;
1514 	c2h_term_req->common.hlen = c2h_term_req_hdr_len;
1515 	c2h_term_req->fes = fes;
1516 
1517 	if ((fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
1518 	    (fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
1519 		DSET32(&c2h_term_req->fei, error_offset);
1520 	}
1521 
1522 	copy_len = spdk_min(pdu->hdr.common.hlen, SPDK_NVME_TCP_TERM_REQ_ERROR_DATA_MAX_SIZE);
1523 
1524 	/* Copy the error info into the buffer */
1525 	memcpy((uint8_t *)rsp_pdu->hdr.raw + c2h_term_req_hdr_len, pdu->hdr.raw, copy_len);
1526 	nvme_tcp_pdu_set_data(rsp_pdu, (uint8_t *)rsp_pdu->hdr.raw + c2h_term_req_hdr_len, copy_len);
1527 
1528 	/* Contain the header of the wrong received pdu */
1529 	c2h_term_req->common.plen = c2h_term_req->common.hlen + copy_len;
1530 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1531 	nvmf_tcp_qpair_write_mgmt_pdu(tqpair, nvmf_tcp_send_c2h_term_req_complete, tqpair);
1532 }
1533 
1534 static void
1535 nvmf_tcp_capsule_cmd_hdr_handle(struct spdk_nvmf_tcp_transport *ttransport,
1536 				struct spdk_nvmf_tcp_qpair *tqpair,
1537 				struct nvme_tcp_pdu *pdu)
1538 {
1539 	struct spdk_nvmf_tcp_req *tcp_req;
1540 
1541 	assert(pdu->psh_valid_bytes == pdu->psh_len);
1542 	assert(pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD);
1543 
1544 	tcp_req = nvmf_tcp_req_get(tqpair);
1545 	if (!tcp_req) {
1546 		/* Directly return and make the allocation retry again.  This can happen if we're
1547 		 * using asynchronous writes to send the response to the host or when releasing
1548 		 * zero-copy buffers after a response has been sent.  In both cases, the host might
1549 		 * receive the response before we've finished processing the request and is free to
1550 		 * send another one.
1551 		 */
1552 		if (tqpair->state_cntr[TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST] > 0 ||
1553 		    tqpair->state_cntr[TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE] > 0) {
1554 			return;
1555 		}
1556 
1557 		/* The host sent more commands than the maximum queue depth. */
1558 		SPDK_ERRLOG("Cannot allocate tcp_req on tqpair=%p\n", tqpair);
1559 		nvmf_tcp_qpair_disconnect(tqpair);
1560 		return;
1561 	}
1562 
1563 	pdu->req = tcp_req;
1564 	assert(tcp_req->state == TCP_REQUEST_STATE_NEW);
1565 	nvmf_tcp_req_process(ttransport, tcp_req);
1566 }
1567 
1568 static void
1569 nvmf_tcp_capsule_cmd_payload_handle(struct spdk_nvmf_tcp_transport *ttransport,
1570 				    struct spdk_nvmf_tcp_qpair *tqpair,
1571 				    struct nvme_tcp_pdu *pdu)
1572 {
1573 	struct spdk_nvmf_tcp_req *tcp_req;
1574 	struct spdk_nvme_tcp_cmd *capsule_cmd;
1575 	uint32_t error_offset = 0;
1576 	enum spdk_nvme_tcp_term_req_fes fes;
1577 	struct spdk_nvme_cpl *rsp;
1578 
1579 	capsule_cmd = &pdu->hdr.capsule_cmd;
1580 	tcp_req = pdu->req;
1581 	assert(tcp_req != NULL);
1582 
1583 	/* Zero-copy requests don't support ICD */
1584 	assert(!spdk_nvmf_request_using_zcopy(&tcp_req->req));
1585 
1586 	if (capsule_cmd->common.pdo > SPDK_NVME_TCP_PDU_PDO_MAX_OFFSET) {
1587 		SPDK_ERRLOG("Expected ICReq capsule_cmd pdu offset <= %d, got %c\n",
1588 			    SPDK_NVME_TCP_PDU_PDO_MAX_OFFSET, capsule_cmd->common.pdo);
1589 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1590 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdo);
1591 		goto err;
1592 	}
1593 
1594 	rsp = &tcp_req->req.rsp->nvme_cpl;
1595 	if (spdk_unlikely(rsp->status.sc == SPDK_NVME_SC_COMMAND_TRANSIENT_TRANSPORT_ERROR)) {
1596 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
1597 	} else {
1598 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1599 	}
1600 
1601 	nvmf_tcp_req_process(ttransport, tcp_req);
1602 
1603 	return;
1604 err:
1605 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1606 }
1607 
1608 static void
1609 nvmf_tcp_h2c_data_hdr_handle(struct spdk_nvmf_tcp_transport *ttransport,
1610 			     struct spdk_nvmf_tcp_qpair *tqpair,
1611 			     struct nvme_tcp_pdu *pdu)
1612 {
1613 	struct spdk_nvmf_tcp_req *tcp_req;
1614 	uint32_t error_offset = 0;
1615 	enum spdk_nvme_tcp_term_req_fes fes = 0;
1616 	struct spdk_nvme_tcp_h2c_data_hdr *h2c_data;
1617 
1618 	h2c_data = &pdu->hdr.h2c_data;
1619 
1620 	SPDK_DEBUGLOG(nvmf_tcp, "tqpair=%p, r2t_info: datao=%u, datal=%u, cccid=%u, ttag=%u\n",
1621 		      tqpair, h2c_data->datao, h2c_data->datal, h2c_data->cccid, h2c_data->ttag);
1622 
1623 	if (h2c_data->ttag > tqpair->resource_count) {
1624 		SPDK_DEBUGLOG(nvmf_tcp, "ttag %u is larger than allowed %u.\n", h2c_data->ttag,
1625 			      tqpair->resource_count);
1626 		fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
1627 		error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, ttag);
1628 		goto err;
1629 	}
1630 
1631 	tcp_req = &tqpair->reqs[h2c_data->ttag - 1];
1632 
1633 	if (spdk_unlikely(tcp_req->state != TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER &&
1634 			  tcp_req->state != TCP_REQUEST_STATE_AWAITING_R2T_ACK)) {
1635 		SPDK_DEBUGLOG(nvmf_tcp, "tcp_req(%p), tqpair=%p, has error state in %d\n", tcp_req, tqpair,
1636 			      tcp_req->state);
1637 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1638 		error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, ttag);
1639 		goto err;
1640 	}
1641 
1642 	if (spdk_unlikely(tcp_req->req.cmd->nvme_cmd.cid != h2c_data->cccid)) {
1643 		SPDK_DEBUGLOG(nvmf_tcp, "tcp_req(%p), tqpair=%p, expected %u but %u for cccid.\n", tcp_req, tqpair,
1644 			      tcp_req->req.cmd->nvme_cmd.cid, h2c_data->cccid);
1645 		fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
1646 		error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, cccid);
1647 		goto err;
1648 	}
1649 
1650 	if (tcp_req->h2c_offset != h2c_data->datao) {
1651 		SPDK_DEBUGLOG(nvmf_tcp,
1652 			      "tcp_req(%p), tqpair=%p, expected data offset %u, but data offset is %u\n",
1653 			      tcp_req, tqpair, tcp_req->h2c_offset, h2c_data->datao);
1654 		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
1655 		goto err;
1656 	}
1657 
1658 	if ((h2c_data->datao + h2c_data->datal) > tcp_req->req.length) {
1659 		SPDK_DEBUGLOG(nvmf_tcp,
1660 			      "tcp_req(%p), tqpair=%p,  (datao=%u + datal=%u) exceeds requested length=%u\n",
1661 			      tcp_req, tqpair, h2c_data->datao, h2c_data->datal, tcp_req->req.length);
1662 		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
1663 		goto err;
1664 	}
1665 
1666 	pdu->req = tcp_req;
1667 
1668 	if (spdk_unlikely(tcp_req->req.dif_enabled)) {
1669 		pdu->dif_ctx = &tcp_req->req.dif.dif_ctx;
1670 	}
1671 
1672 	nvme_tcp_pdu_set_data_buf(pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
1673 				  h2c_data->datao, h2c_data->datal);
1674 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1675 	return;
1676 
1677 err:
1678 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1679 }
1680 
1681 static void
1682 nvmf_tcp_send_capsule_resp_pdu(struct spdk_nvmf_tcp_req *tcp_req,
1683 			       struct spdk_nvmf_tcp_qpair *tqpair)
1684 {
1685 	struct nvme_tcp_pdu *rsp_pdu;
1686 	struct spdk_nvme_tcp_rsp *capsule_resp;
1687 
1688 	SPDK_DEBUGLOG(nvmf_tcp, "enter, tqpair=%p\n", tqpair);
1689 
1690 	rsp_pdu = nvmf_tcp_req_pdu_init(tcp_req);
1691 	assert(rsp_pdu != NULL);
1692 
1693 	capsule_resp = &rsp_pdu->hdr.capsule_resp;
1694 	capsule_resp->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_CAPSULE_RESP;
1695 	capsule_resp->common.plen = capsule_resp->common.hlen = sizeof(*capsule_resp);
1696 	capsule_resp->rccqe = tcp_req->req.rsp->nvme_cpl;
1697 	if (tqpair->host_hdgst_enable) {
1698 		capsule_resp->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
1699 		capsule_resp->common.plen += SPDK_NVME_TCP_DIGEST_LEN;
1700 	}
1701 
1702 	nvmf_tcp_qpair_write_req_pdu(tqpair, tcp_req, nvmf_tcp_request_free, tcp_req);
1703 }
1704 
1705 static void
1706 nvmf_tcp_pdu_c2h_data_complete(void *cb_arg)
1707 {
1708 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
1709 	struct spdk_nvmf_tcp_qpair *tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair,
1710 					     struct spdk_nvmf_tcp_qpair, qpair);
1711 
1712 	assert(tqpair != NULL);
1713 
1714 	if (spdk_unlikely(tcp_req->pdu->rw_offset < tcp_req->req.length)) {
1715 		SPDK_DEBUGLOG(nvmf_tcp, "sending another C2H part, offset %u length %u\n", tcp_req->pdu->rw_offset,
1716 			      tcp_req->req.length);
1717 		_nvmf_tcp_send_c2h_data(tqpair, tcp_req);
1718 		return;
1719 	}
1720 
1721 	if (tcp_req->pdu->hdr.c2h_data.common.flags & SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS) {
1722 		nvmf_tcp_request_free(tcp_req);
1723 	} else {
1724 		nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
1725 	}
1726 }
1727 
1728 static void
1729 nvmf_tcp_r2t_complete(void *cb_arg)
1730 {
1731 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
1732 	struct spdk_nvmf_tcp_transport *ttransport;
1733 
1734 	ttransport = SPDK_CONTAINEROF(tcp_req->req.qpair->transport,
1735 				      struct spdk_nvmf_tcp_transport, transport);
1736 
1737 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
1738 
1739 	if (tcp_req->h2c_offset == tcp_req->req.length) {
1740 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1741 		nvmf_tcp_req_process(ttransport, tcp_req);
1742 	}
1743 }
1744 
1745 static void
1746 nvmf_tcp_send_r2t_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
1747 		      struct spdk_nvmf_tcp_req *tcp_req)
1748 {
1749 	struct nvme_tcp_pdu *rsp_pdu;
1750 	struct spdk_nvme_tcp_r2t_hdr *r2t;
1751 
1752 	rsp_pdu = nvmf_tcp_req_pdu_init(tcp_req);
1753 	assert(rsp_pdu != NULL);
1754 
1755 	r2t = &rsp_pdu->hdr.r2t;
1756 	r2t->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_R2T;
1757 	r2t->common.plen = r2t->common.hlen = sizeof(*r2t);
1758 
1759 	if (tqpair->host_hdgst_enable) {
1760 		r2t->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
1761 		r2t->common.plen += SPDK_NVME_TCP_DIGEST_LEN;
1762 	}
1763 
1764 	r2t->cccid = tcp_req->req.cmd->nvme_cmd.cid;
1765 	r2t->ttag = tcp_req->ttag;
1766 	r2t->r2to = tcp_req->h2c_offset;
1767 	r2t->r2tl = tcp_req->req.length;
1768 
1769 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_R2T_ACK);
1770 
1771 	SPDK_DEBUGLOG(nvmf_tcp,
1772 		      "tcp_req(%p) on tqpair(%p), r2t_info: cccid=%u, ttag=%u, r2to=%u, r2tl=%u\n",
1773 		      tcp_req, tqpair, r2t->cccid, r2t->ttag, r2t->r2to, r2t->r2tl);
1774 	nvmf_tcp_qpair_write_req_pdu(tqpair, tcp_req, nvmf_tcp_r2t_complete, tcp_req);
1775 }
1776 
1777 static void
1778 nvmf_tcp_h2c_data_payload_handle(struct spdk_nvmf_tcp_transport *ttransport,
1779 				 struct spdk_nvmf_tcp_qpair *tqpair,
1780 				 struct nvme_tcp_pdu *pdu)
1781 {
1782 	struct spdk_nvmf_tcp_req *tcp_req;
1783 	struct spdk_nvme_cpl *rsp;
1784 
1785 	tcp_req = pdu->req;
1786 	assert(tcp_req != NULL);
1787 
1788 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
1789 
1790 	tcp_req->h2c_offset += pdu->data_len;
1791 
1792 	/* Wait for all of the data to arrive AND for the initial R2T PDU send to be
1793 	 * acknowledged before moving on. */
1794 	if (tcp_req->h2c_offset == tcp_req->req.length &&
1795 	    tcp_req->state == TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER) {
1796 		/* After receiving all the h2c data, we need to check whether there is
1797 		 * transient transport error */
1798 		rsp = &tcp_req->req.rsp->nvme_cpl;
1799 		if (spdk_unlikely(rsp->status.sc == SPDK_NVME_SC_COMMAND_TRANSIENT_TRANSPORT_ERROR)) {
1800 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
1801 		} else {
1802 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1803 		}
1804 		nvmf_tcp_req_process(ttransport, tcp_req);
1805 	}
1806 }
1807 
1808 static void
1809 nvmf_tcp_h2c_term_req_dump(struct spdk_nvme_tcp_term_req_hdr *h2c_term_req)
1810 {
1811 	SPDK_ERRLOG("Error info of pdu(%p): %s\n", h2c_term_req,
1812 		    spdk_nvmf_tcp_term_req_fes_str[h2c_term_req->fes]);
1813 	if ((h2c_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
1814 	    (h2c_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
1815 		SPDK_DEBUGLOG(nvmf_tcp, "The offset from the start of the PDU header is %u\n",
1816 			      DGET32(h2c_term_req->fei));
1817 	}
1818 }
1819 
1820 static void
1821 nvmf_tcp_h2c_term_req_hdr_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1822 				 struct nvme_tcp_pdu *pdu)
1823 {
1824 	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req = &pdu->hdr.term_req;
1825 	uint32_t error_offset = 0;
1826 	enum spdk_nvme_tcp_term_req_fes fes;
1827 
1828 	if (h2c_term_req->fes > SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER) {
1829 		SPDK_ERRLOG("Fatal Error Status(FES) is unknown for h2c_term_req pdu=%p\n", pdu);
1830 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1831 		error_offset = offsetof(struct spdk_nvme_tcp_term_req_hdr, fes);
1832 		goto end;
1833 	}
1834 
1835 	/* set the data buffer */
1836 	nvme_tcp_pdu_set_data(pdu, (uint8_t *)pdu->hdr.raw + h2c_term_req->common.hlen,
1837 			      h2c_term_req->common.plen - h2c_term_req->common.hlen);
1838 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1839 	return;
1840 end:
1841 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1842 }
1843 
1844 static void
1845 nvmf_tcp_h2c_term_req_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1846 				     struct nvme_tcp_pdu *pdu)
1847 {
1848 	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req = &pdu->hdr.term_req;
1849 
1850 	nvmf_tcp_h2c_term_req_dump(h2c_term_req);
1851 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1852 }
1853 
1854 static void
1855 _nvmf_tcp_pdu_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu)
1856 {
1857 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport,
1858 			struct spdk_nvmf_tcp_transport, transport);
1859 
1860 	switch (pdu->hdr.common.pdu_type) {
1861 	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
1862 		nvmf_tcp_capsule_cmd_payload_handle(ttransport, tqpair, pdu);
1863 		break;
1864 	case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
1865 		nvmf_tcp_h2c_data_payload_handle(ttransport, tqpair, pdu);
1866 		break;
1867 
1868 	case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
1869 		nvmf_tcp_h2c_term_req_payload_handle(tqpair, pdu);
1870 		break;
1871 
1872 	default:
1873 		/* The code should not go to here */
1874 		SPDK_ERRLOG("ERROR pdu type %d\n", pdu->hdr.common.pdu_type);
1875 		break;
1876 	}
1877 	SLIST_INSERT_HEAD(&tqpair->tcp_pdu_free_queue, pdu, slist);
1878 }
1879 
1880 static void
1881 data_crc32_calc_done(void *cb_arg, int status)
1882 {
1883 	struct nvme_tcp_pdu *pdu = cb_arg;
1884 	struct spdk_nvmf_tcp_qpair *tqpair = pdu->qpair;
1885 	struct spdk_nvmf_tcp_req *tcp_req;
1886 	struct spdk_nvme_cpl *rsp;
1887 
1888 	/* async crc32 calculation is failed and use direct calculation to check */
1889 	if (spdk_unlikely(status)) {
1890 		SPDK_ERRLOG("Data digest on tqpair=(%p) with pdu=%p failed to be calculated asynchronously\n",
1891 			    tqpair, pdu);
1892 		pdu->data_digest_crc32 = nvme_tcp_pdu_calc_data_digest(pdu);
1893 	}
1894 	pdu->data_digest_crc32 ^= SPDK_CRC32C_XOR;
1895 	if (!MATCH_DIGEST_WORD(pdu->data_digest, pdu->data_digest_crc32)) {
1896 		SPDK_ERRLOG("Data digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
1897 		tcp_req = pdu->req;
1898 		assert(tcp_req != NULL);
1899 		rsp = &tcp_req->req.rsp->nvme_cpl;
1900 		rsp->status.sc = SPDK_NVME_SC_COMMAND_TRANSIENT_TRANSPORT_ERROR;
1901 	}
1902 	_nvmf_tcp_pdu_payload_handle(tqpair, pdu);
1903 }
1904 
1905 static void
1906 nvmf_tcp_pdu_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu)
1907 {
1908 	int rc = 0;
1909 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1910 	tqpair->pdu_in_progress = NULL;
1911 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1912 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
1913 	/* check data digest if need */
1914 	if (pdu->ddgst_enable) {
1915 		if (tqpair->qpair.qid != 0 && !pdu->dif_ctx && tqpair->group &&
1916 		    (pdu->data_len % SPDK_NVME_TCP_DIGEST_ALIGNMENT == 0)) {
1917 			rc = spdk_accel_submit_crc32cv(tqpair->group->accel_channel, &pdu->data_digest_crc32, pdu->data_iov,
1918 						       pdu->data_iovcnt, 0, data_crc32_calc_done, pdu);
1919 			if (spdk_likely(rc == 0)) {
1920 				return;
1921 			}
1922 		} else {
1923 			pdu->data_digest_crc32 = nvme_tcp_pdu_calc_data_digest(pdu);
1924 		}
1925 		data_crc32_calc_done(pdu, rc);
1926 	} else {
1927 		_nvmf_tcp_pdu_payload_handle(tqpair, pdu);
1928 	}
1929 }
1930 
1931 static void
1932 nvmf_tcp_send_icresp_complete(void *cb_arg)
1933 {
1934 	struct spdk_nvmf_tcp_qpair *tqpair = cb_arg;
1935 
1936 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_RUNNING);
1937 }
1938 
1939 static void
1940 nvmf_tcp_icreq_handle(struct spdk_nvmf_tcp_transport *ttransport,
1941 		      struct spdk_nvmf_tcp_qpair *tqpair,
1942 		      struct nvme_tcp_pdu *pdu)
1943 {
1944 	struct spdk_nvme_tcp_ic_req *ic_req = &pdu->hdr.ic_req;
1945 	struct nvme_tcp_pdu *rsp_pdu;
1946 	struct spdk_nvme_tcp_ic_resp *ic_resp;
1947 	uint32_t error_offset = 0;
1948 	enum spdk_nvme_tcp_term_req_fes fes;
1949 
1950 	/* Only PFV 0 is defined currently */
1951 	if (ic_req->pfv != 0) {
1952 		SPDK_ERRLOG("Expected ICReq PFV %u, got %u\n", 0u, ic_req->pfv);
1953 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1954 		error_offset = offsetof(struct spdk_nvme_tcp_ic_req, pfv);
1955 		goto end;
1956 	}
1957 
1958 	/* This value is 0’s based value in units of dwords should not be larger than SPDK_NVME_TCP_HPDA_MAX */
1959 	if (ic_req->hpda > SPDK_NVME_TCP_HPDA_MAX) {
1960 		SPDK_ERRLOG("ICReq HPDA out of range 0 to 31, got %u\n", ic_req->hpda);
1961 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1962 		error_offset = offsetof(struct spdk_nvme_tcp_ic_req, hpda);
1963 		goto end;
1964 	}
1965 
1966 	/* MAXR2T is 0's based */
1967 	SPDK_DEBUGLOG(nvmf_tcp, "maxr2t =%u\n", (ic_req->maxr2t + 1u));
1968 
1969 	tqpair->host_hdgst_enable = ic_req->dgst.bits.hdgst_enable ? true : false;
1970 	if (!tqpair->host_hdgst_enable) {
1971 		tqpair->recv_buf_size -= SPDK_NVME_TCP_DIGEST_LEN * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
1972 	}
1973 
1974 	tqpair->host_ddgst_enable = ic_req->dgst.bits.ddgst_enable ? true : false;
1975 	if (!tqpair->host_ddgst_enable) {
1976 		tqpair->recv_buf_size -= SPDK_NVME_TCP_DIGEST_LEN * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
1977 	}
1978 
1979 	tqpair->recv_buf_size = spdk_max(tqpair->recv_buf_size, MIN_SOCK_PIPE_SIZE);
1980 	/* Now that we know whether digests are enabled, properly size the receive buffer */
1981 	if (spdk_sock_set_recvbuf(tqpair->sock, tqpair->recv_buf_size) < 0) {
1982 		SPDK_WARNLOG("Unable to allocate enough memory for receive buffer on tqpair=%p with size=%d\n",
1983 			     tqpair,
1984 			     tqpair->recv_buf_size);
1985 		/* Not fatal. */
1986 	}
1987 
1988 	tqpair->cpda = spdk_min(ic_req->hpda, SPDK_NVME_TCP_CPDA_MAX);
1989 	SPDK_DEBUGLOG(nvmf_tcp, "cpda of tqpair=(%p) is : %u\n", tqpair, tqpair->cpda);
1990 
1991 	rsp_pdu = tqpair->mgmt_pdu;
1992 
1993 	ic_resp = &rsp_pdu->hdr.ic_resp;
1994 	ic_resp->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_IC_RESP;
1995 	ic_resp->common.hlen = ic_resp->common.plen =  sizeof(*ic_resp);
1996 	ic_resp->pfv = 0;
1997 	ic_resp->cpda = tqpair->cpda;
1998 	ic_resp->maxh2cdata = ttransport->transport.opts.max_io_size;
1999 	ic_resp->dgst.bits.hdgst_enable = tqpair->host_hdgst_enable ? 1 : 0;
2000 	ic_resp->dgst.bits.ddgst_enable = tqpair->host_ddgst_enable ? 1 : 0;
2001 
2002 	SPDK_DEBUGLOG(nvmf_tcp, "host_hdgst_enable: %u\n", tqpair->host_hdgst_enable);
2003 	SPDK_DEBUGLOG(nvmf_tcp, "host_ddgst_enable: %u\n", tqpair->host_ddgst_enable);
2004 
2005 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_INITIALIZING);
2006 	nvmf_tcp_qpair_write_mgmt_pdu(tqpair, nvmf_tcp_send_icresp_complete, tqpair);
2007 	nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2008 	return;
2009 end:
2010 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
2011 }
2012 
2013 static void
2014 nvmf_tcp_pdu_psh_handle(struct spdk_nvmf_tcp_qpair *tqpair,
2015 			struct spdk_nvmf_tcp_transport *ttransport)
2016 {
2017 	struct nvme_tcp_pdu *pdu;
2018 	int rc;
2019 	uint32_t crc32c, error_offset = 0;
2020 	enum spdk_nvme_tcp_term_req_fes fes;
2021 
2022 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
2023 	pdu = tqpair->pdu_in_progress;
2024 
2025 	SPDK_DEBUGLOG(nvmf_tcp, "pdu type of tqpair(%p) is %d\n", tqpair,
2026 		      pdu->hdr.common.pdu_type);
2027 	/* check header digest if needed */
2028 	if (pdu->has_hdgst) {
2029 		SPDK_DEBUGLOG(nvmf_tcp, "Compare the header of pdu=%p on tqpair=%p\n", pdu, tqpair);
2030 		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
2031 		rc = MATCH_DIGEST_WORD((uint8_t *)pdu->hdr.raw + pdu->hdr.common.hlen, crc32c);
2032 		if (rc == 0) {
2033 			SPDK_ERRLOG("Header digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
2034 			fes = SPDK_NVME_TCP_TERM_REQ_FES_HDGST_ERROR;
2035 			nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
2036 			return;
2037 
2038 		}
2039 	}
2040 
2041 	switch (pdu->hdr.common.pdu_type) {
2042 	case SPDK_NVME_TCP_PDU_TYPE_IC_REQ:
2043 		nvmf_tcp_icreq_handle(ttransport, tqpair, pdu);
2044 		break;
2045 	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
2046 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_REQ);
2047 		break;
2048 	case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
2049 		nvmf_tcp_h2c_data_hdr_handle(ttransport, tqpair, pdu);
2050 		break;
2051 
2052 	case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
2053 		nvmf_tcp_h2c_term_req_hdr_handle(tqpair, pdu);
2054 		break;
2055 
2056 	default:
2057 		SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", tqpair->pdu_in_progress->hdr.common.pdu_type);
2058 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2059 		error_offset = 1;
2060 		nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
2061 		break;
2062 	}
2063 }
2064 
2065 static void
2066 nvmf_tcp_pdu_ch_handle(struct spdk_nvmf_tcp_qpair *tqpair)
2067 {
2068 	struct nvme_tcp_pdu *pdu;
2069 	uint32_t error_offset = 0;
2070 	enum spdk_nvme_tcp_term_req_fes fes;
2071 	uint8_t expected_hlen, pdo;
2072 	bool plen_error = false, pdo_error = false;
2073 
2074 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
2075 	pdu = tqpair->pdu_in_progress;
2076 	assert(pdu);
2077 	if (pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_REQ) {
2078 		if (tqpair->state != NVME_TCP_QPAIR_STATE_INVALID) {
2079 			SPDK_ERRLOG("Already received ICreq PDU, and reject this pdu=%p\n", pdu);
2080 			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
2081 			goto err;
2082 		}
2083 		expected_hlen = sizeof(struct spdk_nvme_tcp_ic_req);
2084 		if (pdu->hdr.common.plen != expected_hlen) {
2085 			plen_error = true;
2086 		}
2087 	} else {
2088 		if (tqpair->state != NVME_TCP_QPAIR_STATE_RUNNING) {
2089 			SPDK_ERRLOG("The TCP/IP connection is not negotiated\n");
2090 			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
2091 			goto err;
2092 		}
2093 
2094 		switch (pdu->hdr.common.pdu_type) {
2095 		case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
2096 			expected_hlen = sizeof(struct spdk_nvme_tcp_cmd);
2097 			pdo = pdu->hdr.common.pdo;
2098 			if ((tqpair->cpda != 0) && (pdo % ((tqpair->cpda + 1) << 2) != 0)) {
2099 				pdo_error = true;
2100 				break;
2101 			}
2102 
2103 			if (pdu->hdr.common.plen < expected_hlen) {
2104 				plen_error = true;
2105 			}
2106 			break;
2107 		case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
2108 			expected_hlen = sizeof(struct spdk_nvme_tcp_h2c_data_hdr);
2109 			pdo = pdu->hdr.common.pdo;
2110 			if ((tqpair->cpda != 0) && (pdo % ((tqpair->cpda + 1) << 2) != 0)) {
2111 				pdo_error = true;
2112 				break;
2113 			}
2114 			if (pdu->hdr.common.plen < expected_hlen) {
2115 				plen_error = true;
2116 			}
2117 			break;
2118 
2119 		case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
2120 			expected_hlen = sizeof(struct spdk_nvme_tcp_term_req_hdr);
2121 			if ((pdu->hdr.common.plen <= expected_hlen) ||
2122 			    (pdu->hdr.common.plen > SPDK_NVME_TCP_TERM_REQ_PDU_MAX_SIZE)) {
2123 				plen_error = true;
2124 			}
2125 			break;
2126 
2127 		default:
2128 			SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", pdu->hdr.common.pdu_type);
2129 			fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2130 			error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdu_type);
2131 			goto err;
2132 		}
2133 	}
2134 
2135 	if (pdu->hdr.common.hlen != expected_hlen) {
2136 		SPDK_ERRLOG("PDU type=0x%02x, Expected ICReq header length %u, got %u on tqpair=%p\n",
2137 			    pdu->hdr.common.pdu_type,
2138 			    expected_hlen, pdu->hdr.common.hlen, tqpair);
2139 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2140 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, hlen);
2141 		goto err;
2142 	} else if (pdo_error) {
2143 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2144 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdo);
2145 	} else if (plen_error) {
2146 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2147 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, plen);
2148 		goto err;
2149 	} else {
2150 		nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
2151 		nvme_tcp_pdu_calc_psh_len(tqpair->pdu_in_progress, tqpair->host_hdgst_enable);
2152 		return;
2153 	}
2154 err:
2155 	nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
2156 }
2157 
2158 static int
2159 nvmf_tcp_sock_process(struct spdk_nvmf_tcp_qpair *tqpair)
2160 {
2161 	int rc = 0;
2162 	struct nvme_tcp_pdu *pdu;
2163 	enum nvme_tcp_pdu_recv_state prev_state;
2164 	uint32_t data_len;
2165 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport,
2166 			struct spdk_nvmf_tcp_transport, transport);
2167 
2168 	/* The loop here is to allow for several back-to-back state changes. */
2169 	do {
2170 		prev_state = tqpair->recv_state;
2171 		SPDK_DEBUGLOG(nvmf_tcp, "tqpair(%p) recv pdu entering state %d\n", tqpair, prev_state);
2172 
2173 		pdu = tqpair->pdu_in_progress;
2174 		assert(pdu || tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2175 		switch (tqpair->recv_state) {
2176 		/* Wait for the common header  */
2177 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY:
2178 			if (!pdu) {
2179 				pdu = SLIST_FIRST(&tqpair->tcp_pdu_free_queue);
2180 				if (spdk_unlikely(!pdu)) {
2181 					return NVME_TCP_PDU_IN_PROGRESS;
2182 				}
2183 				SLIST_REMOVE_HEAD(&tqpair->tcp_pdu_free_queue, slist);
2184 				tqpair->pdu_in_progress = pdu;
2185 			}
2186 			memset(pdu, 0, offsetof(struct nvme_tcp_pdu, qpair));
2187 			nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
2188 		/* FALLTHROUGH */
2189 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH:
2190 			if (spdk_unlikely(tqpair->state == NVME_TCP_QPAIR_STATE_INITIALIZING)) {
2191 				return rc;
2192 			}
2193 
2194 			rc = nvme_tcp_read_data(tqpair->sock,
2195 						sizeof(struct spdk_nvme_tcp_common_pdu_hdr) - pdu->ch_valid_bytes,
2196 						(void *)&pdu->hdr.common + pdu->ch_valid_bytes);
2197 			if (rc < 0) {
2198 				SPDK_DEBUGLOG(nvmf_tcp, "will disconnect tqpair=%p\n", tqpair);
2199 				return NVME_TCP_PDU_FATAL;
2200 			} else if (rc > 0) {
2201 				pdu->ch_valid_bytes += rc;
2202 				spdk_trace_record(TRACE_TCP_READ_FROM_SOCKET_DONE, tqpair->qpair.qid, rc, 0, tqpair);
2203 			}
2204 
2205 			if (pdu->ch_valid_bytes < sizeof(struct spdk_nvme_tcp_common_pdu_hdr)) {
2206 				return NVME_TCP_PDU_IN_PROGRESS;
2207 			}
2208 
2209 			/* The command header of this PDU has now been read from the socket. */
2210 			nvmf_tcp_pdu_ch_handle(tqpair);
2211 			break;
2212 		/* Wait for the pdu specific header  */
2213 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH:
2214 			rc = nvme_tcp_read_data(tqpair->sock,
2215 						pdu->psh_len - pdu->psh_valid_bytes,
2216 						(void *)&pdu->hdr.raw + sizeof(struct spdk_nvme_tcp_common_pdu_hdr) + pdu->psh_valid_bytes);
2217 			if (rc < 0) {
2218 				return NVME_TCP_PDU_FATAL;
2219 			} else if (rc > 0) {
2220 				spdk_trace_record(TRACE_TCP_READ_FROM_SOCKET_DONE, tqpair->qpair.qid, rc, 0, tqpair);
2221 				pdu->psh_valid_bytes += rc;
2222 			}
2223 
2224 			if (pdu->psh_valid_bytes < pdu->psh_len) {
2225 				return NVME_TCP_PDU_IN_PROGRESS;
2226 			}
2227 
2228 			/* All header(ch, psh, head digist) of this PDU has now been read from the socket. */
2229 			nvmf_tcp_pdu_psh_handle(tqpair, ttransport);
2230 			break;
2231 		/* Wait for the req slot */
2232 		case NVME_TCP_PDU_RECV_STATE_AWAIT_REQ:
2233 			nvmf_tcp_capsule_cmd_hdr_handle(ttransport, tqpair, pdu);
2234 			break;
2235 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:
2236 			/* check whether the data is valid, if not we just return */
2237 			if (!pdu->data_len) {
2238 				return NVME_TCP_PDU_IN_PROGRESS;
2239 			}
2240 
2241 			data_len = pdu->data_len;
2242 			/* data digest */
2243 			if (spdk_unlikely((pdu->hdr.common.pdu_type != SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ) &&
2244 					  tqpair->host_ddgst_enable)) {
2245 				data_len += SPDK_NVME_TCP_DIGEST_LEN;
2246 				pdu->ddgst_enable = true;
2247 			}
2248 
2249 			rc = nvme_tcp_read_payload_data(tqpair->sock, pdu);
2250 			if (rc < 0) {
2251 				return NVME_TCP_PDU_FATAL;
2252 			}
2253 			pdu->rw_offset += rc;
2254 
2255 			if (pdu->rw_offset < data_len) {
2256 				return NVME_TCP_PDU_IN_PROGRESS;
2257 			}
2258 
2259 			/* Generate and insert DIF to whole data block received if DIF is enabled */
2260 			if (spdk_unlikely(pdu->dif_ctx != NULL) &&
2261 			    spdk_dif_generate_stream(pdu->data_iov, pdu->data_iovcnt, 0, data_len,
2262 						     pdu->dif_ctx) != 0) {
2263 				SPDK_ERRLOG("DIF generate failed\n");
2264 				return NVME_TCP_PDU_FATAL;
2265 			}
2266 
2267 			/* All of this PDU has now been read from the socket. */
2268 			nvmf_tcp_pdu_payload_handle(tqpair, pdu);
2269 			break;
2270 		case NVME_TCP_PDU_RECV_STATE_ERROR:
2271 			if (!spdk_sock_is_connected(tqpair->sock)) {
2272 				return NVME_TCP_PDU_FATAL;
2273 			}
2274 			break;
2275 		default:
2276 			SPDK_ERRLOG("The state(%d) is invalid\n", tqpair->recv_state);
2277 			abort();
2278 			break;
2279 		}
2280 	} while (tqpair->recv_state != prev_state);
2281 
2282 	return rc;
2283 }
2284 
2285 static inline void *
2286 nvmf_tcp_control_msg_get(struct spdk_nvmf_tcp_control_msg_list *list)
2287 {
2288 	struct spdk_nvmf_tcp_control_msg *msg;
2289 
2290 	assert(list);
2291 
2292 	msg = STAILQ_FIRST(&list->free_msgs);
2293 	if (!msg) {
2294 		SPDK_DEBUGLOG(nvmf_tcp, "Out of control messages\n");
2295 		return NULL;
2296 	}
2297 	STAILQ_REMOVE_HEAD(&list->free_msgs, link);
2298 	return msg;
2299 }
2300 
2301 static inline void
2302 nvmf_tcp_control_msg_put(struct spdk_nvmf_tcp_control_msg_list *list, void *_msg)
2303 {
2304 	struct spdk_nvmf_tcp_control_msg *msg = _msg;
2305 
2306 	assert(list);
2307 	STAILQ_INSERT_HEAD(&list->free_msgs, msg, link);
2308 }
2309 
2310 static int
2311 nvmf_tcp_req_parse_sgl(struct spdk_nvmf_tcp_req *tcp_req,
2312 		       struct spdk_nvmf_transport *transport,
2313 		       struct spdk_nvmf_transport_poll_group *group)
2314 {
2315 	struct spdk_nvmf_request		*req = &tcp_req->req;
2316 	struct spdk_nvme_cmd			*cmd;
2317 	struct spdk_nvme_sgl_descriptor		*sgl;
2318 	struct spdk_nvmf_tcp_poll_group		*tgroup;
2319 	enum spdk_nvme_tcp_term_req_fes		fes;
2320 	struct nvme_tcp_pdu			*pdu;
2321 	struct spdk_nvmf_tcp_qpair		*tqpair;
2322 	uint32_t				length, error_offset = 0;
2323 
2324 	cmd = &req->cmd->nvme_cmd;
2325 	sgl = &cmd->dptr.sgl1;
2326 
2327 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK &&
2328 	    sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_TRANSPORT) {
2329 		/* get request length from sgl */
2330 		length = sgl->unkeyed.length;
2331 		if (spdk_unlikely(length > transport->opts.max_io_size)) {
2332 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
2333 				    length, transport->opts.max_io_size);
2334 			fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_LIMIT_EXCEEDED;
2335 			goto fatal_err;
2336 		}
2337 
2338 		/* fill request length and populate iovs */
2339 		req->length = length;
2340 
2341 		SPDK_DEBUGLOG(nvmf_tcp, "Data requested length= 0x%x\n", length);
2342 
2343 		if (spdk_unlikely(req->dif_enabled)) {
2344 			req->dif.orig_length = length;
2345 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
2346 			req->dif.elba_length = length;
2347 		}
2348 
2349 		if (nvmf_ctrlr_use_zcopy(req)) {
2350 			SPDK_DEBUGLOG(nvmf_tcp, "Using zero-copy to execute request %p\n", tcp_req);
2351 			req->data_from_pool = false;
2352 			return 0;
2353 		}
2354 
2355 		if (spdk_nvmf_request_get_buffers(req, group, transport, length)) {
2356 			/* No available buffers. Queue this request up. */
2357 			SPDK_DEBUGLOG(nvmf_tcp, "No available large data buffers. Queueing request %p\n",
2358 				      tcp_req);
2359 			return 0;
2360 		}
2361 
2362 		/* backward compatible */
2363 		req->data = req->iov[0].iov_base;
2364 
2365 		SPDK_DEBUGLOG(nvmf_tcp, "Request %p took %d buffer/s from central pool, and data=%p\n",
2366 			      tcp_req, req->iovcnt, req->iov[0].iov_base);
2367 
2368 		return 0;
2369 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
2370 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
2371 		uint64_t offset = sgl->address;
2372 		uint32_t max_len = transport->opts.in_capsule_data_size;
2373 
2374 		assert(tcp_req->has_in_capsule_data);
2375 		/* Capsule Cmd with In-capsule Data should get data length from pdu header */
2376 		tqpair = tcp_req->pdu->qpair;
2377 		/* receiving pdu is not same with the pdu in tcp_req */
2378 		pdu = tqpair->pdu_in_progress;
2379 		length = pdu->hdr.common.plen - pdu->psh_len - sizeof(struct spdk_nvme_tcp_common_pdu_hdr);
2380 		if (tqpair->host_ddgst_enable) {
2381 			length -= SPDK_NVME_TCP_DIGEST_LEN;
2382 		}
2383 		/* This error is not defined in NVMe/TCP spec, take this error as fatal error */
2384 		if (spdk_unlikely(length != sgl->unkeyed.length)) {
2385 			SPDK_ERRLOG("In-Capsule Data length 0x%x is not equal to SGL data length 0x%x\n",
2386 				    length, sgl->unkeyed.length);
2387 			fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
2388 			error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, plen);
2389 			goto fatal_err;
2390 		}
2391 
2392 		SPDK_DEBUGLOG(nvmf_tcp, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
2393 			      offset, length);
2394 
2395 		/* The NVMe/TCP transport does not use ICDOFF to control the in-capsule data offset. ICDOFF should be '0' */
2396 		if (spdk_unlikely(offset != 0)) {
2397 			/* Not defined fatal error in NVMe/TCP spec, handle this error as a fatal error */
2398 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " should be ZERO in NVMe/TCP\n", offset);
2399 			fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER;
2400 			error_offset = offsetof(struct spdk_nvme_tcp_cmd, ccsqe.dptr.sgl1.address);
2401 			goto fatal_err;
2402 		}
2403 
2404 		if (spdk_unlikely(length > max_len)) {
2405 			/* According to the SPEC we should support ICD up to 8192 bytes for admin and fabric commands */
2406 			if (length <= SPDK_NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE &&
2407 			    (cmd->opc == SPDK_NVME_OPC_FABRIC || req->qpair->qid == 0)) {
2408 
2409 				/* Get a buffer from dedicated list */
2410 				SPDK_DEBUGLOG(nvmf_tcp, "Getting a buffer from control msg list\n");
2411 				tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2412 				assert(tgroup->control_msg_list);
2413 				req->iov[0].iov_base = nvmf_tcp_control_msg_get(tgroup->control_msg_list);
2414 				if (!req->iov[0].iov_base) {
2415 					/* No available buffers. Queue this request up. */
2416 					SPDK_DEBUGLOG(nvmf_tcp, "No available ICD buffers. Queueing request %p\n", tcp_req);
2417 					return 0;
2418 				}
2419 			} else {
2420 				SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
2421 					    length, max_len);
2422 				fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_LIMIT_EXCEEDED;
2423 				goto fatal_err;
2424 			}
2425 		} else {
2426 			req->iov[0].iov_base = tcp_req->buf;
2427 		}
2428 
2429 		req->length = length;
2430 		req->data_from_pool = false;
2431 		req->data = req->iov[0].iov_base;
2432 
2433 		if (spdk_unlikely(req->dif_enabled)) {
2434 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
2435 			req->dif.elba_length = length;
2436 		}
2437 
2438 		req->iov[0].iov_len = length;
2439 		req->iovcnt = 1;
2440 
2441 		return 0;
2442 	}
2443 	/* If we want to handle the problem here, then we can't skip the following data segment.
2444 	 * Because this function runs before reading data part, now handle all errors as fatal errors. */
2445 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
2446 		    sgl->generic.type, sgl->generic.subtype);
2447 	fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER;
2448 	error_offset = offsetof(struct spdk_nvme_tcp_cmd, ccsqe.dptr.sgl1.generic);
2449 fatal_err:
2450 	nvmf_tcp_send_c2h_term_req(tcp_req->pdu->qpair, tcp_req->pdu, fes, error_offset);
2451 	return -1;
2452 }
2453 
2454 static inline enum spdk_nvme_media_error_status_code
2455 nvmf_tcp_dif_error_to_compl_status(uint8_t err_type) {
2456 	enum spdk_nvme_media_error_status_code result;
2457 
2458 	switch (err_type)
2459 	{
2460 	case SPDK_DIF_REFTAG_ERROR:
2461 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
2462 		break;
2463 	case SPDK_DIF_APPTAG_ERROR:
2464 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
2465 		break;
2466 	case SPDK_DIF_GUARD_ERROR:
2467 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
2468 		break;
2469 	default:
2470 		SPDK_UNREACHABLE();
2471 		break;
2472 	}
2473 
2474 	return result;
2475 }
2476 
2477 static void
2478 _nvmf_tcp_send_c2h_data(struct spdk_nvmf_tcp_qpair *tqpair,
2479 			struct spdk_nvmf_tcp_req *tcp_req)
2480 {
2481 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(
2482 				tqpair->qpair.transport, struct spdk_nvmf_tcp_transport, transport);
2483 	struct nvme_tcp_pdu *rsp_pdu;
2484 	struct spdk_nvme_tcp_c2h_data_hdr *c2h_data;
2485 	uint32_t plen, pdo, alignment;
2486 	int rc;
2487 
2488 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
2489 
2490 	rsp_pdu = tcp_req->pdu;
2491 	assert(rsp_pdu != NULL);
2492 
2493 	c2h_data = &rsp_pdu->hdr.c2h_data;
2494 	c2h_data->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_C2H_DATA;
2495 	plen = c2h_data->common.hlen = sizeof(*c2h_data);
2496 
2497 	if (tqpair->host_hdgst_enable) {
2498 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2499 		c2h_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
2500 	}
2501 
2502 	/* set the psh */
2503 	c2h_data->cccid = tcp_req->req.cmd->nvme_cmd.cid;
2504 	c2h_data->datal = tcp_req->req.length - tcp_req->pdu->rw_offset;
2505 	c2h_data->datao = tcp_req->pdu->rw_offset;
2506 
2507 	/* set the padding */
2508 	rsp_pdu->padding_len = 0;
2509 	pdo = plen;
2510 	if (tqpair->cpda) {
2511 		alignment = (tqpair->cpda + 1) << 2;
2512 		if (plen % alignment != 0) {
2513 			pdo = (plen + alignment) / alignment * alignment;
2514 			rsp_pdu->padding_len = pdo - plen;
2515 			plen = pdo;
2516 		}
2517 	}
2518 
2519 	c2h_data->common.pdo = pdo;
2520 	plen += c2h_data->datal;
2521 	if (tqpair->host_ddgst_enable) {
2522 		c2h_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_DDGSTF;
2523 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2524 	}
2525 
2526 	c2h_data->common.plen = plen;
2527 
2528 	if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2529 		rsp_pdu->dif_ctx = &tcp_req->req.dif.dif_ctx;
2530 	}
2531 
2532 	nvme_tcp_pdu_set_data_buf(rsp_pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
2533 				  c2h_data->datao, c2h_data->datal);
2534 
2535 
2536 	c2h_data->common.flags |= SPDK_NVME_TCP_C2H_DATA_FLAGS_LAST_PDU;
2537 	/* Need to send the capsule response if response is not all 0 */
2538 	if (ttransport->tcp_opts.c2h_success &&
2539 	    tcp_req->rsp.cdw0 == 0 && tcp_req->rsp.cdw1 == 0) {
2540 		c2h_data->common.flags |= SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS;
2541 	}
2542 
2543 	if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2544 		struct spdk_nvme_cpl *rsp = &tcp_req->req.rsp->nvme_cpl;
2545 		struct spdk_dif_error err_blk = {};
2546 		uint32_t mapped_length = 0;
2547 		uint32_t available_iovs = SPDK_COUNTOF(rsp_pdu->iov);
2548 		uint32_t ddgst_len = 0;
2549 
2550 		if (tqpair->host_ddgst_enable) {
2551 			/* Data digest consumes additional iov entry */
2552 			available_iovs--;
2553 			/* plen needs to be updated since nvme_tcp_build_iovs compares expected and actual plen */
2554 			ddgst_len = SPDK_NVME_TCP_DIGEST_LEN;
2555 			c2h_data->common.plen -= ddgst_len;
2556 		}
2557 		/* Temp call to estimate if data can be described by limited number of iovs.
2558 		 * iov vector will be rebuilt in nvmf_tcp_qpair_write_pdu */
2559 		nvme_tcp_build_iovs(rsp_pdu->iov, available_iovs, rsp_pdu, tqpair->host_hdgst_enable,
2560 				    false, &mapped_length);
2561 
2562 		if (mapped_length != c2h_data->common.plen) {
2563 			c2h_data->datal = mapped_length - (c2h_data->common.plen - c2h_data->datal);
2564 			SPDK_DEBUGLOG(nvmf_tcp,
2565 				      "Part C2H, data_len %u (of %u), PDU len %u, updated PDU len %u, offset %u\n",
2566 				      c2h_data->datal, tcp_req->req.length, c2h_data->common.plen, mapped_length, rsp_pdu->rw_offset);
2567 			c2h_data->common.plen = mapped_length;
2568 
2569 			/* Rebuild pdu->data_iov since data length is changed */
2570 			nvme_tcp_pdu_set_data_buf(rsp_pdu, tcp_req->req.iov, tcp_req->req.iovcnt, c2h_data->datao,
2571 						  c2h_data->datal);
2572 
2573 			c2h_data->common.flags &= ~(SPDK_NVME_TCP_C2H_DATA_FLAGS_LAST_PDU |
2574 						    SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS);
2575 		}
2576 
2577 		c2h_data->common.plen += ddgst_len;
2578 
2579 		assert(rsp_pdu->rw_offset <= tcp_req->req.length);
2580 
2581 		rc = spdk_dif_verify_stream(rsp_pdu->data_iov, rsp_pdu->data_iovcnt,
2582 					    0, rsp_pdu->data_len, rsp_pdu->dif_ctx, &err_blk);
2583 		if (rc != 0) {
2584 			SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n",
2585 				    err_blk.err_type, err_blk.err_offset);
2586 			rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2587 			rsp->status.sc = nvmf_tcp_dif_error_to_compl_status(err_blk.err_type);
2588 			nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
2589 			return;
2590 		}
2591 	}
2592 
2593 	rsp_pdu->rw_offset += c2h_data->datal;
2594 	nvmf_tcp_qpair_write_req_pdu(tqpair, tcp_req, nvmf_tcp_pdu_c2h_data_complete, tcp_req);
2595 }
2596 
2597 static void
2598 nvmf_tcp_send_c2h_data(struct spdk_nvmf_tcp_qpair *tqpair,
2599 		       struct spdk_nvmf_tcp_req *tcp_req)
2600 {
2601 	nvmf_tcp_req_pdu_init(tcp_req);
2602 	_nvmf_tcp_send_c2h_data(tqpair, tcp_req);
2603 }
2604 
2605 static int
2606 request_transfer_out(struct spdk_nvmf_request *req)
2607 {
2608 	struct spdk_nvmf_tcp_req	*tcp_req;
2609 	struct spdk_nvmf_qpair		*qpair;
2610 	struct spdk_nvmf_tcp_qpair	*tqpair;
2611 	struct spdk_nvme_cpl		*rsp;
2612 
2613 	SPDK_DEBUGLOG(nvmf_tcp, "enter\n");
2614 
2615 	qpair = req->qpair;
2616 	rsp = &req->rsp->nvme_cpl;
2617 	tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
2618 
2619 	/* Advance our sq_head pointer */
2620 	if (qpair->sq_head == qpair->sq_head_max) {
2621 		qpair->sq_head = 0;
2622 	} else {
2623 		qpair->sq_head++;
2624 	}
2625 	rsp->sqhd = qpair->sq_head;
2626 
2627 	tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
2628 	nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST);
2629 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS && req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2630 		nvmf_tcp_send_c2h_data(tqpair, tcp_req);
2631 	} else {
2632 		nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
2633 	}
2634 
2635 	return 0;
2636 }
2637 
2638 static void
2639 nvmf_tcp_check_fused_ordering(struct spdk_nvmf_tcp_transport *ttransport,
2640 			      struct spdk_nvmf_tcp_qpair *tqpair,
2641 			      struct spdk_nvmf_tcp_req *tcp_req)
2642 {
2643 	enum spdk_nvme_cmd_fuse last, next;
2644 
2645 	last = tqpair->fused_first ? tqpair->fused_first->cmd.fuse : SPDK_NVME_CMD_FUSE_NONE;
2646 	next = tcp_req->cmd.fuse;
2647 
2648 	assert(last != SPDK_NVME_CMD_FUSE_SECOND);
2649 
2650 	if (spdk_likely(last == SPDK_NVME_CMD_FUSE_NONE && next == SPDK_NVME_CMD_FUSE_NONE)) {
2651 		return;
2652 	}
2653 
2654 	if (last == SPDK_NVME_CMD_FUSE_FIRST) {
2655 		if (next == SPDK_NVME_CMD_FUSE_SECOND) {
2656 			/* This is a valid pair of fused commands.  Point them at each other
2657 			 * so they can be submitted consecutively once ready to be executed.
2658 			 */
2659 			tqpair->fused_first->fused_pair = tcp_req;
2660 			tcp_req->fused_pair = tqpair->fused_first;
2661 			tqpair->fused_first = NULL;
2662 			return;
2663 		} else {
2664 			/* Mark the last req as failed since it wasn't followed by a SECOND. */
2665 			tqpair->fused_first->fused_failed = true;
2666 
2667 			/*
2668 			 * If the last req is in READY_TO_EXECUTE state, then call
2669 			 * nvmf_tcp_req_process(), otherwise nothing else will kick it.
2670 			 */
2671 			if (tqpair->fused_first->state == TCP_REQUEST_STATE_READY_TO_EXECUTE) {
2672 				nvmf_tcp_req_process(ttransport, tqpair->fused_first);
2673 			}
2674 
2675 			tqpair->fused_first = NULL;
2676 		}
2677 	}
2678 
2679 	if (next == SPDK_NVME_CMD_FUSE_FIRST) {
2680 		/* Set tqpair->fused_first here so that we know to check that the next request
2681 		 * is a SECOND (and to fail this one if it isn't).
2682 		 */
2683 		tqpair->fused_first = tcp_req;
2684 	} else if (next == SPDK_NVME_CMD_FUSE_SECOND) {
2685 		/* Mark this req failed since it is a SECOND and the last one was not a FIRST. */
2686 		tcp_req->fused_failed = true;
2687 	}
2688 }
2689 
2690 static bool
2691 nvmf_tcp_req_process(struct spdk_nvmf_tcp_transport *ttransport,
2692 		     struct spdk_nvmf_tcp_req *tcp_req)
2693 {
2694 	struct spdk_nvmf_tcp_qpair		*tqpair;
2695 	uint32_t				plen;
2696 	struct nvme_tcp_pdu			*pdu;
2697 	enum spdk_nvmf_tcp_req_state		prev_state;
2698 	bool					progress = false;
2699 	struct spdk_nvmf_transport		*transport = &ttransport->transport;
2700 	struct spdk_nvmf_transport_poll_group	*group;
2701 	struct spdk_nvmf_tcp_poll_group		*tgroup;
2702 
2703 	tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
2704 	group = &tqpair->group->group;
2705 	assert(tcp_req->state != TCP_REQUEST_STATE_FREE);
2706 
2707 	/* If the qpair is not active, we need to abort the outstanding requests. */
2708 	if (tqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE) {
2709 		if (tcp_req->state == TCP_REQUEST_STATE_NEED_BUFFER) {
2710 			STAILQ_REMOVE(&group->pending_buf_queue, &tcp_req->req, spdk_nvmf_request, buf_link);
2711 		}
2712 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
2713 	}
2714 
2715 	/* The loop here is to allow for several back-to-back state changes. */
2716 	do {
2717 		prev_state = tcp_req->state;
2718 
2719 		SPDK_DEBUGLOG(nvmf_tcp, "Request %p entering state %d on tqpair=%p\n", tcp_req, prev_state,
2720 			      tqpair);
2721 
2722 		switch (tcp_req->state) {
2723 		case TCP_REQUEST_STATE_FREE:
2724 			/* Some external code must kick a request into TCP_REQUEST_STATE_NEW
2725 			 * to escape this state. */
2726 			break;
2727 		case TCP_REQUEST_STATE_NEW:
2728 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_NEW, tqpair->qpair.qid, 0, (uintptr_t)tcp_req, tqpair);
2729 
2730 			/* copy the cmd from the receive pdu */
2731 			tcp_req->cmd = tqpair->pdu_in_progress->hdr.capsule_cmd.ccsqe;
2732 
2733 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&tcp_req->req, &tcp_req->req.dif.dif_ctx))) {
2734 				tcp_req->req.dif_enabled = true;
2735 				tqpair->pdu_in_progress->dif_ctx = &tcp_req->req.dif.dif_ctx;
2736 			}
2737 
2738 			nvmf_tcp_check_fused_ordering(ttransport, tqpair, tcp_req);
2739 
2740 			/* The next state transition depends on the data transfer needs of this request. */
2741 			tcp_req->req.xfer = spdk_nvmf_req_get_xfer(&tcp_req->req);
2742 
2743 			if (spdk_unlikely(tcp_req->req.xfer == SPDK_NVME_DATA_BIDIRECTIONAL)) {
2744 				tcp_req->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
2745 				tcp_req->req.rsp->nvme_cpl.status.sc  = SPDK_NVME_SC_INVALID_OPCODE;
2746 				tcp_req->req.rsp->nvme_cpl.cid = tcp_req->req.cmd->nvme_cmd.cid;
2747 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2748 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2749 				SPDK_DEBUGLOG(nvmf_tcp, "Request %p: invalid xfer type (BIDIRECTIONAL)\n", tcp_req);
2750 				break;
2751 			}
2752 
2753 			/* If no data to transfer, ready to execute. */
2754 			if (tcp_req->req.xfer == SPDK_NVME_DATA_NONE) {
2755 				/* Reset the tqpair receiving pdu state */
2756 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2757 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
2758 				break;
2759 			}
2760 
2761 			pdu = tqpair->pdu_in_progress;
2762 			plen = pdu->hdr.common.hlen;
2763 			if (tqpair->host_hdgst_enable) {
2764 				plen += SPDK_NVME_TCP_DIGEST_LEN;
2765 			}
2766 			if (pdu->hdr.common.plen != plen) {
2767 				tcp_req->has_in_capsule_data = true;
2768 			} else {
2769 				/* Data is transmitted by C2H PDUs */
2770 				nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2771 			}
2772 
2773 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEED_BUFFER);
2774 			STAILQ_INSERT_TAIL(&group->pending_buf_queue, &tcp_req->req, buf_link);
2775 			break;
2776 		case TCP_REQUEST_STATE_NEED_BUFFER:
2777 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_NEED_BUFFER, tqpair->qpair.qid, 0, (uintptr_t)tcp_req,
2778 					  tqpair);
2779 
2780 			assert(tcp_req->req.xfer != SPDK_NVME_DATA_NONE);
2781 
2782 			if (!tcp_req->has_in_capsule_data && (&tcp_req->req != STAILQ_FIRST(&group->pending_buf_queue))) {
2783 				SPDK_DEBUGLOG(nvmf_tcp,
2784 					      "Not the first element to wait for the buf for tcp_req(%p) on tqpair=%p\n",
2785 					      tcp_req, tqpair);
2786 				/* This request needs to wait in line to obtain a buffer */
2787 				break;
2788 			}
2789 
2790 			/* Try to get a data buffer */
2791 			if (nvmf_tcp_req_parse_sgl(tcp_req, transport, group) < 0) {
2792 				break;
2793 			}
2794 
2795 			/* Get a zcopy buffer if the request can be serviced through zcopy */
2796 			if (spdk_nvmf_request_using_zcopy(&tcp_req->req)) {
2797 				if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2798 					assert(tcp_req->req.dif.elba_length >= tcp_req->req.length);
2799 					tcp_req->req.length = tcp_req->req.dif.elba_length;
2800 				}
2801 
2802 				STAILQ_REMOVE(&group->pending_buf_queue, &tcp_req->req, spdk_nvmf_request, buf_link);
2803 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_ZCOPY_START);
2804 				spdk_nvmf_request_zcopy_start(&tcp_req->req);
2805 				break;
2806 			}
2807 
2808 			if (tcp_req->req.iovcnt < 1) {
2809 				SPDK_DEBUGLOG(nvmf_tcp, "No buffer allocated for tcp_req(%p) on tqpair(%p\n)",
2810 					      tcp_req, tqpair);
2811 				/* No buffers available. */
2812 				break;
2813 			}
2814 
2815 			STAILQ_REMOVE(&group->pending_buf_queue, &tcp_req->req, spdk_nvmf_request, buf_link);
2816 
2817 			/* If data is transferring from host to controller, we need to do a transfer from the host. */
2818 			if (tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2819 				if (tcp_req->req.data_from_pool) {
2820 					SPDK_DEBUGLOG(nvmf_tcp, "Sending R2T for tcp_req(%p) on tqpair=%p\n", tcp_req, tqpair);
2821 					nvmf_tcp_send_r2t_pdu(tqpair, tcp_req);
2822 				} else {
2823 					struct nvme_tcp_pdu *pdu;
2824 
2825 					nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
2826 
2827 					pdu = tqpair->pdu_in_progress;
2828 					SPDK_DEBUGLOG(nvmf_tcp, "Not need to send r2t for tcp_req(%p) on tqpair=%p\n", tcp_req,
2829 						      tqpair);
2830 					/* No need to send r2t, contained in the capsuled data */
2831 					nvme_tcp_pdu_set_data_buf(pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
2832 								  0, tcp_req->req.length);
2833 					nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
2834 				}
2835 				break;
2836 			}
2837 
2838 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
2839 			break;
2840 		case TCP_REQUEST_STATE_AWAITING_ZCOPY_START:
2841 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_START, tqpair->qpair.qid, 0,
2842 					  (uintptr_t)tcp_req, tqpair);
2843 			/* Some external code must kick a request into  TCP_REQUEST_STATE_ZCOPY_START_COMPLETED
2844 			 * to escape this state. */
2845 			break;
2846 		case TCP_REQUEST_STATE_ZCOPY_START_COMPLETED:
2847 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_ZCOPY_START_COMPLETED, tqpair->qpair.qid, 0,
2848 					  (uintptr_t)tcp_req, tqpair);
2849 			if (spdk_unlikely(spdk_nvme_cpl_is_error(&tcp_req->req.rsp->nvme_cpl))) {
2850 				SPDK_DEBUGLOG(nvmf_tcp, "Zero-copy start failed for tcp_req(%p) on tqpair=%p\n",
2851 					      tcp_req, tqpair);
2852 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2853 				break;
2854 			}
2855 			if (tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2856 				SPDK_DEBUGLOG(nvmf_tcp, "Sending R2T for tcp_req(%p) on tqpair=%p\n", tcp_req, tqpair);
2857 				nvmf_tcp_send_r2t_pdu(tqpair, tcp_req);
2858 			} else {
2859 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTED);
2860 			}
2861 			break;
2862 		case TCP_REQUEST_STATE_AWAITING_R2T_ACK:
2863 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_R2T_ACK, tqpair->qpair.qid, 0, (uintptr_t)tcp_req,
2864 					  tqpair);
2865 			/* The R2T completion or the h2c data incoming will kick it out of this state. */
2866 			break;
2867 		case TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2868 
2869 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, tqpair->qpair.qid, 0,
2870 					  (uintptr_t)tcp_req, tqpair);
2871 			/* Some external code must kick a request into TCP_REQUEST_STATE_READY_TO_EXECUTE
2872 			 * to escape this state. */
2873 			break;
2874 		case TCP_REQUEST_STATE_READY_TO_EXECUTE:
2875 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE, tqpair->qpair.qid, 0,
2876 					  (uintptr_t)tcp_req, tqpair);
2877 
2878 			if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2879 				assert(tcp_req->req.dif.elba_length >= tcp_req->req.length);
2880 				tcp_req->req.length = tcp_req->req.dif.elba_length;
2881 			}
2882 
2883 			if (tcp_req->cmd.fuse != SPDK_NVME_CMD_FUSE_NONE) {
2884 				if (tcp_req->fused_failed) {
2885 					/* This request failed FUSED semantics.  Fail it immediately, without
2886 					 * even sending it to the target layer.
2887 					 */
2888 					tcp_req->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
2889 					tcp_req->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_MISSING_FUSED;
2890 					tcp_req->req.rsp->nvme_cpl.cid = tcp_req->req.cmd->nvme_cmd.cid;
2891 					nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2892 					break;
2893 				}
2894 
2895 				if (tcp_req->fused_pair == NULL ||
2896 				    tcp_req->fused_pair->state != TCP_REQUEST_STATE_READY_TO_EXECUTE) {
2897 					/* This request is ready to execute, but either we don't know yet if it's
2898 					 * valid - i.e. this is a FIRST but we haven't received the next request yet),
2899 					 * or the other request of this fused pair isn't ready to execute. So
2900 					 * break here and this request will get processed later either when the
2901 					 * other request is ready or we find that this request isn't valid.
2902 					 */
2903 					break;
2904 				}
2905 			}
2906 
2907 			if (!spdk_nvmf_request_using_zcopy(&tcp_req->req)) {
2908 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTING);
2909 				/* If we get to this point, and this request is a fused command, we know that
2910 				 * it is part of a valid sequence (FIRST followed by a SECOND) and that both
2911 				 * requests are READY_TO_EXECUTE.  So call spdk_nvmf_request_exec() both on this
2912 				 * request, and the other request of the fused pair, in the correct order.
2913 				 * Also clear the ->fused_pair pointers on both requests, since after this point
2914 				 * we no longer need to maintain the relationship between these two requests.
2915 				 */
2916 				if (tcp_req->cmd.fuse == SPDK_NVME_CMD_FUSE_SECOND) {
2917 					assert(tcp_req->fused_pair != NULL);
2918 					assert(tcp_req->fused_pair->fused_pair == tcp_req);
2919 					nvmf_tcp_req_set_state(tcp_req->fused_pair, TCP_REQUEST_STATE_EXECUTING);
2920 					spdk_nvmf_request_exec(&tcp_req->fused_pair->req);
2921 					tcp_req->fused_pair->fused_pair = NULL;
2922 					tcp_req->fused_pair = NULL;
2923 				}
2924 				spdk_nvmf_request_exec(&tcp_req->req);
2925 				if (tcp_req->cmd.fuse == SPDK_NVME_CMD_FUSE_FIRST) {
2926 					assert(tcp_req->fused_pair != NULL);
2927 					assert(tcp_req->fused_pair->fused_pair == tcp_req);
2928 					nvmf_tcp_req_set_state(tcp_req->fused_pair, TCP_REQUEST_STATE_EXECUTING);
2929 					spdk_nvmf_request_exec(&tcp_req->fused_pair->req);
2930 					tcp_req->fused_pair->fused_pair = NULL;
2931 					tcp_req->fused_pair = NULL;
2932 				}
2933 			} else {
2934 				/* For zero-copy, only requests with data coming from host to the
2935 				 * controller can end up here. */
2936 				assert(tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER);
2937 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT);
2938 				spdk_nvmf_request_zcopy_end(&tcp_req->req, true);
2939 			}
2940 
2941 			break;
2942 		case TCP_REQUEST_STATE_EXECUTING:
2943 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_EXECUTING, tqpair->qpair.qid, 0, (uintptr_t)tcp_req,
2944 					  tqpair);
2945 			/* Some external code must kick a request into TCP_REQUEST_STATE_EXECUTED
2946 			 * to escape this state. */
2947 			break;
2948 		case TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT:
2949 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_COMMIT, tqpair->qpair.qid, 0,
2950 					  (uintptr_t)tcp_req, tqpair);
2951 			/* Some external code must kick a request into TCP_REQUEST_STATE_EXECUTED
2952 			 * to escape this state. */
2953 			break;
2954 		case TCP_REQUEST_STATE_EXECUTED:
2955 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_EXECUTED, tqpair->qpair.qid, 0, (uintptr_t)tcp_req,
2956 					  tqpair);
2957 
2958 			if (spdk_unlikely(tcp_req->req.dif_enabled)) {
2959 				tcp_req->req.length = tcp_req->req.dif.orig_length;
2960 			}
2961 
2962 			nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2963 			break;
2964 		case TCP_REQUEST_STATE_READY_TO_COMPLETE:
2965 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE, tqpair->qpair.qid, 0,
2966 					  (uintptr_t)tcp_req, tqpair);
2967 			if (request_transfer_out(&tcp_req->req) != 0) {
2968 				assert(0); /* No good way to handle this currently */
2969 			}
2970 			break;
2971 		case TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2972 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, tqpair->qpair.qid, 0,
2973 					  (uintptr_t)tcp_req, tqpair);
2974 			/* Some external code must kick a request into TCP_REQUEST_STATE_COMPLETED
2975 			 * to escape this state. */
2976 			break;
2977 		case TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE:
2978 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_ZCOPY_RELEASE, tqpair->qpair.qid, 0,
2979 					  (uintptr_t)tcp_req, tqpair);
2980 			/* Some external code must kick a request into TCP_REQUEST_STATE_COMPLETED
2981 			 * to escape this state. */
2982 			break;
2983 		case TCP_REQUEST_STATE_COMPLETED:
2984 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_COMPLETED, tqpair->qpair.qid, 0, (uintptr_t)tcp_req,
2985 					  tqpair);
2986 			/* If there's an outstanding PDU sent to the host, the request is completed
2987 			 * due to the qpair being disconnected.  We must delay the completion until
2988 			 * that write is done to avoid freeing the request twice. */
2989 			if (spdk_unlikely(tcp_req->pdu_in_use)) {
2990 				SPDK_DEBUGLOG(nvmf_tcp, "Delaying completion due to outstanding "
2991 					      "write on req=%p\n", tcp_req);
2992 				/* This can only happen for zcopy requests */
2993 				assert(spdk_nvmf_request_using_zcopy(&tcp_req->req));
2994 				assert(tqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE);
2995 				break;
2996 			}
2997 
2998 			if (tcp_req->req.data_from_pool) {
2999 				spdk_nvmf_request_free_buffers(&tcp_req->req, group, transport);
3000 			} else if (spdk_unlikely(tcp_req->has_in_capsule_data &&
3001 						 (tcp_req->cmd.opc == SPDK_NVME_OPC_FABRIC ||
3002 						  tqpair->qpair.qid == 0) && tcp_req->req.length > transport->opts.in_capsule_data_size)) {
3003 				tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
3004 				assert(tgroup->control_msg_list);
3005 				SPDK_DEBUGLOG(nvmf_tcp, "Put buf to control msg list\n");
3006 				nvmf_tcp_control_msg_put(tgroup->control_msg_list,
3007 							 tcp_req->req.iov[0].iov_base);
3008 			} else if (tcp_req->req.zcopy_bdev_io != NULL) {
3009 				/* If the request has an unreleased zcopy bdev_io, it's either a
3010 				 * read, a failed write, or the qpair is being disconnected */
3011 				assert(spdk_nvmf_request_using_zcopy(&tcp_req->req));
3012 				assert(tcp_req->req.xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST ||
3013 				       spdk_nvme_cpl_is_error(&tcp_req->req.rsp->nvme_cpl) ||
3014 				       tqpair->qpair.state != SPDK_NVMF_QPAIR_ACTIVE);
3015 				nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE);
3016 				spdk_nvmf_request_zcopy_end(&tcp_req->req, false);
3017 				break;
3018 			}
3019 			tcp_req->req.length = 0;
3020 			tcp_req->req.iovcnt = 0;
3021 			tcp_req->req.data = NULL;
3022 			tcp_req->fused_failed = false;
3023 			if (tcp_req->fused_pair) {
3024 				/* This req was part of a valid fused pair, but failed before it got to
3025 				 * READ_TO_EXECUTE state.  This means we need to fail the other request
3026 				 * in the pair, because it is no longer part of a valid pair.  If the pair
3027 				 * already reached READY_TO_EXECUTE state, we need to kick it.
3028 				 */
3029 				tcp_req->fused_pair->fused_failed = true;
3030 				if (tcp_req->fused_pair->state == TCP_REQUEST_STATE_READY_TO_EXECUTE) {
3031 					nvmf_tcp_req_process(ttransport, tcp_req->fused_pair);
3032 				}
3033 				tcp_req->fused_pair = NULL;
3034 			}
3035 
3036 			nvmf_tcp_req_put(tqpair, tcp_req);
3037 			break;
3038 		case TCP_REQUEST_NUM_STATES:
3039 		default:
3040 			assert(0);
3041 			break;
3042 		}
3043 
3044 		if (tcp_req->state != prev_state) {
3045 			progress = true;
3046 		}
3047 	} while (tcp_req->state != prev_state);
3048 
3049 	return progress;
3050 }
3051 
3052 static void
3053 nvmf_tcp_sock_cb(void *arg, struct spdk_sock_group *group, struct spdk_sock *sock)
3054 {
3055 	struct spdk_nvmf_tcp_qpair *tqpair = arg;
3056 	int rc;
3057 
3058 	assert(tqpair != NULL);
3059 	rc = nvmf_tcp_sock_process(tqpair);
3060 
3061 	/* If there was a new socket error, disconnect */
3062 	if (rc < 0) {
3063 		nvmf_tcp_qpair_disconnect(tqpair);
3064 	}
3065 }
3066 
3067 static int
3068 nvmf_tcp_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
3069 			struct spdk_nvmf_qpair *qpair)
3070 {
3071 	struct spdk_nvmf_tcp_poll_group	*tgroup;
3072 	struct spdk_nvmf_tcp_qpair	*tqpair;
3073 	int				rc;
3074 
3075 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
3076 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3077 
3078 	rc =  nvmf_tcp_qpair_sock_init(tqpair);
3079 	if (rc != 0) {
3080 		SPDK_ERRLOG("Cannot set sock opt for tqpair=%p\n", tqpair);
3081 		return -1;
3082 	}
3083 
3084 	rc = nvmf_tcp_qpair_init(&tqpair->qpair);
3085 	if (rc < 0) {
3086 		SPDK_ERRLOG("Cannot init tqpair=%p\n", tqpair);
3087 		return -1;
3088 	}
3089 
3090 	rc = nvmf_tcp_qpair_init_mem_resource(tqpair);
3091 	if (rc < 0) {
3092 		SPDK_ERRLOG("Cannot init memory resource info for tqpair=%p\n", tqpair);
3093 		return -1;
3094 	}
3095 
3096 	rc = spdk_sock_group_add_sock(tgroup->sock_group, tqpair->sock,
3097 				      nvmf_tcp_sock_cb, tqpair);
3098 	if (rc != 0) {
3099 		SPDK_ERRLOG("Could not add sock to sock_group: %s (%d)\n",
3100 			    spdk_strerror(errno), errno);
3101 		return -1;
3102 	}
3103 
3104 	tqpair->group = tgroup;
3105 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_INVALID);
3106 	TAILQ_INSERT_TAIL(&tgroup->qpairs, tqpair, link);
3107 
3108 	return 0;
3109 }
3110 
3111 static int
3112 nvmf_tcp_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
3113 			   struct spdk_nvmf_qpair *qpair)
3114 {
3115 	struct spdk_nvmf_tcp_poll_group	*tgroup;
3116 	struct spdk_nvmf_tcp_qpair		*tqpair;
3117 	int				rc;
3118 
3119 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
3120 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3121 
3122 	assert(tqpair->group == tgroup);
3123 
3124 	SPDK_DEBUGLOG(nvmf_tcp, "remove tqpair=%p from the tgroup=%p\n", tqpair, tgroup);
3125 	if (tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_REQ) {
3126 		TAILQ_REMOVE(&tgroup->await_req, tqpair, link);
3127 	} else {
3128 		TAILQ_REMOVE(&tgroup->qpairs, tqpair, link);
3129 	}
3130 
3131 	rc = spdk_sock_group_remove_sock(tgroup->sock_group, tqpair->sock);
3132 	if (rc != 0) {
3133 		SPDK_ERRLOG("Could not remove sock from sock_group: %s (%d)\n",
3134 			    spdk_strerror(errno), errno);
3135 	}
3136 
3137 	return rc;
3138 }
3139 
3140 static int
3141 nvmf_tcp_req_complete(struct spdk_nvmf_request *req)
3142 {
3143 	struct spdk_nvmf_tcp_transport *ttransport;
3144 	struct spdk_nvmf_tcp_req *tcp_req;
3145 
3146 	ttransport = SPDK_CONTAINEROF(req->qpair->transport, struct spdk_nvmf_tcp_transport, transport);
3147 	tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
3148 
3149 	switch (tcp_req->state) {
3150 	case TCP_REQUEST_STATE_EXECUTING:
3151 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT:
3152 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTED);
3153 		break;
3154 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_START:
3155 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_ZCOPY_START_COMPLETED);
3156 		break;
3157 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_RELEASE:
3158 		nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
3159 		break;
3160 	default:
3161 		assert(0 && "Unexpected request state");
3162 		break;
3163 	}
3164 
3165 	nvmf_tcp_req_process(ttransport, tcp_req);
3166 
3167 	return 0;
3168 }
3169 
3170 static void
3171 nvmf_tcp_close_qpair(struct spdk_nvmf_qpair *qpair,
3172 		     spdk_nvmf_transport_qpair_fini_cb cb_fn, void *cb_arg)
3173 {
3174 	struct spdk_nvmf_tcp_qpair *tqpair;
3175 
3176 	SPDK_DEBUGLOG(nvmf_tcp, "Qpair: %p\n", qpair);
3177 
3178 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3179 
3180 	assert(tqpair->fini_cb_fn == NULL);
3181 	tqpair->fini_cb_fn = cb_fn;
3182 	tqpair->fini_cb_arg = cb_arg;
3183 
3184 	nvmf_tcp_qpair_set_state(tqpair, NVME_TCP_QPAIR_STATE_EXITED);
3185 	nvmf_tcp_qpair_destroy(tqpair);
3186 }
3187 
3188 static int
3189 nvmf_tcp_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
3190 {
3191 	struct spdk_nvmf_tcp_poll_group *tgroup;
3192 	int rc;
3193 	struct spdk_nvmf_request *req, *req_tmp;
3194 	struct spdk_nvmf_tcp_req *tcp_req;
3195 	struct spdk_nvmf_tcp_qpair *tqpair, *tqpair_tmp;
3196 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(group->transport,
3197 			struct spdk_nvmf_tcp_transport, transport);
3198 
3199 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
3200 
3201 	if (spdk_unlikely(TAILQ_EMPTY(&tgroup->qpairs) && TAILQ_EMPTY(&tgroup->await_req))) {
3202 		return 0;
3203 	}
3204 
3205 	STAILQ_FOREACH_SAFE(req, &group->pending_buf_queue, buf_link, req_tmp) {
3206 		tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
3207 		if (nvmf_tcp_req_process(ttransport, tcp_req) == false) {
3208 			break;
3209 		}
3210 	}
3211 
3212 	rc = spdk_sock_group_poll(tgroup->sock_group);
3213 	if (rc < 0) {
3214 		SPDK_ERRLOG("Failed to poll sock_group=%p\n", tgroup->sock_group);
3215 	}
3216 
3217 	TAILQ_FOREACH_SAFE(tqpair, &tgroup->await_req, link, tqpair_tmp) {
3218 		nvmf_tcp_sock_process(tqpair);
3219 	}
3220 
3221 	return rc;
3222 }
3223 
3224 static int
3225 nvmf_tcp_qpair_get_trid(struct spdk_nvmf_qpair *qpair,
3226 			struct spdk_nvme_transport_id *trid, bool peer)
3227 {
3228 	struct spdk_nvmf_tcp_qpair     *tqpair;
3229 	uint16_t			port;
3230 
3231 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3232 	spdk_nvme_trid_populate_transport(trid, SPDK_NVME_TRANSPORT_TCP);
3233 
3234 	if (peer) {
3235 		snprintf(trid->traddr, sizeof(trid->traddr), "%s", tqpair->initiator_addr);
3236 		port = tqpair->initiator_port;
3237 	} else {
3238 		snprintf(trid->traddr, sizeof(trid->traddr), "%s", tqpair->target_addr);
3239 		port = tqpair->target_port;
3240 	}
3241 
3242 	if (spdk_sock_is_ipv4(tqpair->sock)) {
3243 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
3244 	} else if (spdk_sock_is_ipv6(tqpair->sock)) {
3245 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
3246 	} else {
3247 		return -1;
3248 	}
3249 
3250 	snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%d", port);
3251 	return 0;
3252 }
3253 
3254 static int
3255 nvmf_tcp_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
3256 			      struct spdk_nvme_transport_id *trid)
3257 {
3258 	return nvmf_tcp_qpair_get_trid(qpair, trid, 0);
3259 }
3260 
3261 static int
3262 nvmf_tcp_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
3263 			     struct spdk_nvme_transport_id *trid)
3264 {
3265 	return nvmf_tcp_qpair_get_trid(qpair, trid, 1);
3266 }
3267 
3268 static int
3269 nvmf_tcp_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
3270 			       struct spdk_nvme_transport_id *trid)
3271 {
3272 	return nvmf_tcp_qpair_get_trid(qpair, trid, 0);
3273 }
3274 
3275 static void
3276 nvmf_tcp_req_set_abort_status(struct spdk_nvmf_request *req,
3277 			      struct spdk_nvmf_tcp_req *tcp_req_to_abort)
3278 {
3279 	tcp_req_to_abort->req.rsp->nvme_cpl.status.sct = SPDK_NVME_SCT_GENERIC;
3280 	tcp_req_to_abort->req.rsp->nvme_cpl.status.sc = SPDK_NVME_SC_ABORTED_BY_REQUEST;
3281 	tcp_req_to_abort->req.rsp->nvme_cpl.cid = tcp_req_to_abort->req.cmd->nvme_cmd.cid;
3282 
3283 	nvmf_tcp_req_set_state(tcp_req_to_abort, TCP_REQUEST_STATE_READY_TO_COMPLETE);
3284 
3285 	req->rsp->nvme_cpl.cdw0 &= ~1U; /* Command was successfully aborted. */
3286 }
3287 
3288 static int
3289 _nvmf_tcp_qpair_abort_request(void *ctx)
3290 {
3291 	struct spdk_nvmf_request *req = ctx;
3292 	struct spdk_nvmf_tcp_req *tcp_req_to_abort = SPDK_CONTAINEROF(req->req_to_abort,
3293 			struct spdk_nvmf_tcp_req, req);
3294 	struct spdk_nvmf_tcp_qpair *tqpair = SPDK_CONTAINEROF(req->req_to_abort->qpair,
3295 					     struct spdk_nvmf_tcp_qpair, qpair);
3296 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport,
3297 			struct spdk_nvmf_tcp_transport, transport);
3298 	int rc;
3299 
3300 	spdk_poller_unregister(&req->poller);
3301 
3302 	switch (tcp_req_to_abort->state) {
3303 	case TCP_REQUEST_STATE_EXECUTING:
3304 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_START:
3305 	case TCP_REQUEST_STATE_AWAITING_ZCOPY_COMMIT:
3306 		rc = nvmf_ctrlr_abort_request(req);
3307 		if (rc == SPDK_NVMF_REQUEST_EXEC_STATUS_ASYNCHRONOUS) {
3308 			return SPDK_POLLER_BUSY;
3309 		}
3310 		break;
3311 
3312 	case TCP_REQUEST_STATE_NEED_BUFFER:
3313 		STAILQ_REMOVE(&tqpair->group->group.pending_buf_queue,
3314 			      &tcp_req_to_abort->req, spdk_nvmf_request, buf_link);
3315 
3316 		nvmf_tcp_req_set_abort_status(req, tcp_req_to_abort);
3317 		nvmf_tcp_req_process(ttransport, tcp_req_to_abort);
3318 		break;
3319 
3320 	case TCP_REQUEST_STATE_AWAITING_R2T_ACK:
3321 	case TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
3322 		if (spdk_get_ticks() < req->timeout_tsc) {
3323 			req->poller = SPDK_POLLER_REGISTER(_nvmf_tcp_qpair_abort_request, req, 0);
3324 			return SPDK_POLLER_BUSY;
3325 		}
3326 		break;
3327 
3328 	default:
3329 		/* Requests in other states are either un-abortable (e.g.
3330 		 * TRANSFERRING_CONTROLLER_TO_HOST) or should never end up here, as they're
3331 		 * immediately transitioned to other states in nvmf_tcp_req_process() (e.g.
3332 		 * READY_TO_EXECUTE).  But it is fine to end up here, as we'll simply complete the
3333 		 * abort request with the bit0 of dword0 set (command not aborted).
3334 		 */
3335 		break;
3336 	}
3337 
3338 	spdk_nvmf_request_complete(req);
3339 	return SPDK_POLLER_BUSY;
3340 }
3341 
3342 static void
3343 nvmf_tcp_qpair_abort_request(struct spdk_nvmf_qpair *qpair,
3344 			     struct spdk_nvmf_request *req)
3345 {
3346 	struct spdk_nvmf_tcp_qpair *tqpair;
3347 	struct spdk_nvmf_tcp_transport *ttransport;
3348 	struct spdk_nvmf_transport *transport;
3349 	uint16_t cid;
3350 	uint32_t i;
3351 	struct spdk_nvmf_tcp_req *tcp_req_to_abort = NULL;
3352 
3353 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
3354 	ttransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_tcp_transport, transport);
3355 	transport = &ttransport->transport;
3356 
3357 	cid = req->cmd->nvme_cmd.cdw10_bits.abort.cid;
3358 
3359 	for (i = 0; i < tqpair->resource_count; i++) {
3360 		if (tqpair->reqs[i].state != TCP_REQUEST_STATE_FREE &&
3361 		    tqpair->reqs[i].req.cmd->nvme_cmd.cid == cid) {
3362 			tcp_req_to_abort = &tqpair->reqs[i];
3363 			break;
3364 		}
3365 	}
3366 
3367 	spdk_trace_record(TRACE_TCP_QP_ABORT_REQ, qpair->qid, 0, (uintptr_t)req, tqpair);
3368 
3369 	if (tcp_req_to_abort == NULL) {
3370 		spdk_nvmf_request_complete(req);
3371 		return;
3372 	}
3373 
3374 	req->req_to_abort = &tcp_req_to_abort->req;
3375 	req->timeout_tsc = spdk_get_ticks() +
3376 			   transport->opts.abort_timeout_sec * spdk_get_ticks_hz();
3377 	req->poller = NULL;
3378 
3379 	_nvmf_tcp_qpair_abort_request(req);
3380 }
3381 
3382 static void
3383 nvmf_tcp_opts_init(struct spdk_nvmf_transport_opts *opts)
3384 {
3385 	opts->max_queue_depth =		SPDK_NVMF_TCP_DEFAULT_MAX_IO_QUEUE_DEPTH;
3386 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_TCP_DEFAULT_MAX_QPAIRS_PER_CTRLR;
3387 	opts->in_capsule_data_size =	SPDK_NVMF_TCP_DEFAULT_IN_CAPSULE_DATA_SIZE;
3388 	opts->max_io_size =		SPDK_NVMF_TCP_DEFAULT_MAX_IO_SIZE;
3389 	opts->io_unit_size =		SPDK_NVMF_TCP_DEFAULT_IO_UNIT_SIZE;
3390 	opts->max_aq_depth =		SPDK_NVMF_TCP_DEFAULT_MAX_ADMIN_QUEUE_DEPTH;
3391 	opts->num_shared_buffers =	SPDK_NVMF_TCP_DEFAULT_NUM_SHARED_BUFFERS;
3392 	opts->buf_cache_size =		SPDK_NVMF_TCP_DEFAULT_BUFFER_CACHE_SIZE;
3393 	opts->dif_insert_or_strip =	SPDK_NVMF_TCP_DEFAULT_DIF_INSERT_OR_STRIP;
3394 	opts->abort_timeout_sec =	SPDK_NVMF_TCP_DEFAULT_ABORT_TIMEOUT_SEC;
3395 	opts->transport_specific =      NULL;
3396 }
3397 
3398 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_tcp = {
3399 	.name = "TCP",
3400 	.type = SPDK_NVME_TRANSPORT_TCP,
3401 	.opts_init = nvmf_tcp_opts_init,
3402 	.create = nvmf_tcp_create,
3403 	.dump_opts = nvmf_tcp_dump_opts,
3404 	.destroy = nvmf_tcp_destroy,
3405 
3406 	.listen = nvmf_tcp_listen,
3407 	.stop_listen = nvmf_tcp_stop_listen,
3408 
3409 	.listener_discover = nvmf_tcp_discover,
3410 
3411 	.poll_group_create = nvmf_tcp_poll_group_create,
3412 	.get_optimal_poll_group = nvmf_tcp_get_optimal_poll_group,
3413 	.poll_group_destroy = nvmf_tcp_poll_group_destroy,
3414 	.poll_group_add = nvmf_tcp_poll_group_add,
3415 	.poll_group_remove = nvmf_tcp_poll_group_remove,
3416 	.poll_group_poll = nvmf_tcp_poll_group_poll,
3417 
3418 	.req_free = nvmf_tcp_req_free,
3419 	.req_complete = nvmf_tcp_req_complete,
3420 
3421 	.qpair_fini = nvmf_tcp_close_qpair,
3422 	.qpair_get_local_trid = nvmf_tcp_qpair_get_local_trid,
3423 	.qpair_get_peer_trid = nvmf_tcp_qpair_get_peer_trid,
3424 	.qpair_get_listen_trid = nvmf_tcp_qpair_get_listen_trid,
3425 	.qpair_abort_request = nvmf_tcp_qpair_abort_request,
3426 };
3427 
3428 SPDK_NVMF_TRANSPORT_REGISTER(tcp, &spdk_nvmf_transport_tcp);
3429 SPDK_LOG_REGISTER_COMPONENT(nvmf_tcp)
3430