xref: /spdk/lib/nvmf/tcp.c (revision 19d5c3ed8e87dbd240c77ae0ddb5eda25ae99b5f)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation. All rights reserved.
5  *   Copyright (c) 2019, 2020 Mellanox Technologies LTD. All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "spdk/stdinc.h"
35 #include "spdk/crc32.h"
36 #include "spdk/endian.h"
37 #include "spdk/assert.h"
38 #include "spdk/thread.h"
39 #include "spdk/nvmf_transport.h"
40 #include "spdk/sock.h"
41 #include "spdk/string.h"
42 #include "spdk/trace.h"
43 #include "spdk/util.h"
44 
45 #include "spdk_internal/assert.h"
46 #include "spdk_internal/log.h"
47 #include "spdk_internal/nvme_tcp.h"
48 
49 #define NVMF_TCP_MAX_ACCEPT_SOCK_ONE_TIME 16
50 #define SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY 6
51 #define SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR 4
52 
53 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_tcp;
54 
55 /* spdk nvmf related structure */
56 enum spdk_nvmf_tcp_req_state {
57 
58 	/* The request is not currently in use */
59 	TCP_REQUEST_STATE_FREE = 0,
60 
61 	/* Initial state when request first received */
62 	TCP_REQUEST_STATE_NEW,
63 
64 	/* The request is queued until a data buffer is available. */
65 	TCP_REQUEST_STATE_NEED_BUFFER,
66 
67 	/* The request is currently transferring data from the host to the controller. */
68 	TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
69 
70 	/* The request is waiting for the R2T send acknowledgement. */
71 	TCP_REQUEST_STATE_AWAITING_R2T_ACK,
72 
73 	/* The request is ready to execute at the block device */
74 	TCP_REQUEST_STATE_READY_TO_EXECUTE,
75 
76 	/* The request is currently executing at the block device */
77 	TCP_REQUEST_STATE_EXECUTING,
78 
79 	/* The request finished executing at the block device */
80 	TCP_REQUEST_STATE_EXECUTED,
81 
82 	/* The request is ready to send a completion */
83 	TCP_REQUEST_STATE_READY_TO_COMPLETE,
84 
85 	/* The request is currently transferring final pdus from the controller to the host. */
86 	TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
87 
88 	/* The request completed and can be marked free. */
89 	TCP_REQUEST_STATE_COMPLETED,
90 
91 	/* Terminator */
92 	TCP_REQUEST_NUM_STATES,
93 };
94 
95 static const char *spdk_nvmf_tcp_term_req_fes_str[] = {
96 	"Invalid PDU Header Field",
97 	"PDU Sequence Error",
98 	"Header Digiest Error",
99 	"Data Transfer Out of Range",
100 	"R2T Limit Exceeded",
101 	"Unsupported parameter",
102 };
103 
104 #define OBJECT_NVMF_TCP_IO				0x80
105 
106 #define TRACE_GROUP_NVMF_TCP				0x5
107 #define TRACE_TCP_REQUEST_STATE_NEW					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x0)
108 #define TRACE_TCP_REQUEST_STATE_NEED_BUFFER				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x1)
109 #define TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER		SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x2)
110 #define TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x3)
111 #define TRACE_TCP_REQUEST_STATE_EXECUTING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x4)
112 #define TRACE_TCP_REQUEST_STATE_EXECUTED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x5)
113 #define TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x6)
114 #define TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST		SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x7)
115 #define TRACE_TCP_REQUEST_STATE_COMPLETED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x8)
116 #define TRACE_TCP_FLUSH_WRITEBUF_START					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x9)
117 #define TRACE_TCP_FLUSH_WRITEBUF_DONE					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0xA)
118 #define TRACE_TCP_READ_FROM_SOCKET_DONE					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0xB)
119 #define TRACE_TCP_REQUEST_STATE_AWAIT_R2T_ACK				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0xC)
120 
121 SPDK_TRACE_REGISTER_FN(nvmf_tcp_trace, "nvmf_tcp", TRACE_GROUP_NVMF_TCP)
122 {
123 	spdk_trace_register_object(OBJECT_NVMF_TCP_IO, 'r');
124 	spdk_trace_register_description("TCP_REQ_NEW",
125 					TRACE_TCP_REQUEST_STATE_NEW,
126 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 1, 1, "");
127 	spdk_trace_register_description("TCP_REQ_NEED_BUFFER",
128 					TRACE_TCP_REQUEST_STATE_NEED_BUFFER,
129 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
130 	spdk_trace_register_description("TCP_REQ_TX_H_TO_C",
131 					TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
132 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
133 	spdk_trace_register_description("TCP_REQ_RDY_TO_EXECUTE",
134 					TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE,
135 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
136 	spdk_trace_register_description("TCP_REQ_EXECUTING",
137 					TRACE_TCP_REQUEST_STATE_EXECUTING,
138 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
139 	spdk_trace_register_description("TCP_REQ_EXECUTED",
140 					TRACE_TCP_REQUEST_STATE_EXECUTED,
141 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
142 	spdk_trace_register_description("TCP_REQ_RDY_TO_COMPLETE",
143 					TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE,
144 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
145 	spdk_trace_register_description("TCP_REQ_TRANSFER_C2H",
146 					TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
147 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
148 	spdk_trace_register_description("TCP_REQ_COMPLETED",
149 					TRACE_TCP_REQUEST_STATE_COMPLETED,
150 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
151 	spdk_trace_register_description("TCP_WRITE_START",
152 					TRACE_TCP_FLUSH_WRITEBUF_START,
153 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
154 	spdk_trace_register_description("TCP_WRITE_DONE",
155 					TRACE_TCP_FLUSH_WRITEBUF_DONE,
156 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
157 	spdk_trace_register_description("TCP_READ_DONE",
158 					TRACE_TCP_READ_FROM_SOCKET_DONE,
159 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
160 	spdk_trace_register_description("TCP_REQ_AWAIT_R2T_ACK",
161 					TRACE_TCP_REQUEST_STATE_AWAIT_R2T_ACK,
162 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
163 }
164 
165 struct spdk_nvmf_tcp_req  {
166 	struct spdk_nvmf_request		req;
167 	struct spdk_nvme_cpl			rsp;
168 	struct spdk_nvme_cmd			cmd;
169 
170 	/* A PDU that can be used for sending responses. This is
171 	 * not the incoming PDU! */
172 	struct nvme_tcp_pdu			*pdu;
173 
174 	/*
175 	 * The PDU for a request may be used multiple times in serial over
176 	 * the request's lifetime. For example, first to send an R2T, then
177 	 * to send a completion. To catch mistakes where the PDU is used
178 	 * twice at the same time, add a debug flag here for init/fini.
179 	 */
180 	bool					pdu_in_use;
181 
182 	/* In-capsule data buffer */
183 	uint8_t					*buf;
184 
185 	bool					has_incapsule_data;
186 
187 	/* transfer_tag */
188 	uint16_t				ttag;
189 
190 	enum spdk_nvmf_tcp_req_state		state;
191 
192 	/*
193 	 * h2c_offset is used when we receive the h2c_data PDU.
194 	 */
195 	uint32_t				h2c_offset;
196 
197 	STAILQ_ENTRY(spdk_nvmf_tcp_req)		link;
198 	TAILQ_ENTRY(spdk_nvmf_tcp_req)		state_link;
199 };
200 
201 struct nvme_tcp_pdu_recv_buf {
202 	char					*buf;
203 	uint32_t				off;
204 	uint32_t				size;
205 	uint32_t				remain_size;
206 };
207 
208 struct spdk_nvmf_tcp_qpair {
209 	struct spdk_nvmf_qpair			qpair;
210 	struct spdk_nvmf_tcp_poll_group		*group;
211 	struct spdk_nvmf_tcp_port		*port;
212 	struct spdk_sock			*sock;
213 
214 	enum nvme_tcp_pdu_recv_state		recv_state;
215 	enum nvme_tcp_qpair_state		state;
216 
217 	/* PDU being actively received */
218 	struct nvme_tcp_pdu			pdu_in_progress;
219 	struct nvme_tcp_pdu_recv_buf		pdu_recv_buf;
220 
221 	/* This is a spare PDU used for sending special management
222 	 * operations. Primarily, this is used for the initial
223 	 * connection response and c2h termination request. */
224 	struct nvme_tcp_pdu			mgmt_pdu;
225 
226 	TAILQ_HEAD(, nvme_tcp_pdu)		send_queue;
227 
228 	/* Arrays of in-capsule buffers, requests, and pdus.
229 	 * Each array is 'resource_count' number of elements */
230 	void					*bufs;
231 	struct spdk_nvmf_tcp_req		*reqs;
232 	struct nvme_tcp_pdu			*pdus;
233 	uint32_t				resource_count;
234 
235 	/* Queues to track the requests in all states */
236 	TAILQ_HEAD(, spdk_nvmf_tcp_req)		state_queue[TCP_REQUEST_NUM_STATES];
237 	/* Number of requests in each state */
238 	uint32_t				state_cntr[TCP_REQUEST_NUM_STATES];
239 
240 	uint8_t					cpda;
241 
242 	bool					host_hdgst_enable;
243 	bool					host_ddgst_enable;
244 
245 	/* IP address */
246 	char					initiator_addr[SPDK_NVMF_TRADDR_MAX_LEN];
247 	char					target_addr[SPDK_NVMF_TRADDR_MAX_LEN];
248 
249 	/* IP port */
250 	uint16_t				initiator_port;
251 	uint16_t				target_port;
252 
253 	/* Timer used to destroy qpair after detecting transport error issue if initiator does
254 	 *  not close the connection.
255 	 */
256 	struct spdk_poller			*timeout_poller;
257 
258 	TAILQ_ENTRY(spdk_nvmf_tcp_qpair)	link;
259 };
260 
261 struct spdk_nvmf_tcp_poll_group {
262 	struct spdk_nvmf_transport_poll_group	group;
263 	struct spdk_sock_group			*sock_group;
264 
265 	TAILQ_HEAD(, spdk_nvmf_tcp_qpair)	qpairs;
266 	TAILQ_HEAD(, spdk_nvmf_tcp_qpair)	await_req;
267 };
268 
269 struct spdk_nvmf_tcp_port {
270 	struct spdk_nvme_transport_id		trid;
271 	struct spdk_sock			*listen_sock;
272 	uint32_t				ref;
273 	TAILQ_ENTRY(spdk_nvmf_tcp_port)		link;
274 };
275 
276 struct spdk_nvmf_tcp_transport {
277 	struct spdk_nvmf_transport		transport;
278 
279 	pthread_mutex_t				lock;
280 
281 	TAILQ_HEAD(, spdk_nvmf_tcp_port)	ports;
282 };
283 
284 static bool spdk_nvmf_tcp_req_process(struct spdk_nvmf_tcp_transport *ttransport,
285 				      struct spdk_nvmf_tcp_req *tcp_req);
286 
287 static void
288 spdk_nvmf_tcp_req_set_state(struct spdk_nvmf_tcp_req *tcp_req,
289 			    enum spdk_nvmf_tcp_req_state state)
290 {
291 	struct spdk_nvmf_qpair *qpair;
292 	struct spdk_nvmf_tcp_qpair *tqpair;
293 
294 	qpair = tcp_req->req.qpair;
295 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
296 
297 	TAILQ_REMOVE(&tqpair->state_queue[tcp_req->state], tcp_req, state_link);
298 	assert(tqpair->state_cntr[tcp_req->state] > 0);
299 	tqpair->state_cntr[tcp_req->state]--;
300 
301 	TAILQ_INSERT_TAIL(&tqpair->state_queue[state], tcp_req, state_link);
302 	tqpair->state_cntr[state]++;
303 
304 	tcp_req->state = state;
305 }
306 
307 static inline struct nvme_tcp_pdu *
308 nvmf_tcp_req_pdu_init(struct spdk_nvmf_tcp_req *tcp_req)
309 {
310 	assert(tcp_req->pdu_in_use == false);
311 	tcp_req->pdu_in_use = true;
312 
313 	memset(tcp_req->pdu, 0, sizeof(*tcp_req->pdu));
314 	tcp_req->pdu->qpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
315 	tcp_req->pdu->hdr = &tcp_req->pdu->hdr_mem;
316 
317 	return tcp_req->pdu;
318 }
319 
320 static inline void
321 nvmf_tcp_req_pdu_fini(struct spdk_nvmf_tcp_req *tcp_req)
322 {
323 	tcp_req->pdu_in_use = false;
324 }
325 
326 static struct spdk_nvmf_tcp_req *
327 spdk_nvmf_tcp_req_get(struct spdk_nvmf_tcp_qpair *tqpair)
328 {
329 	struct spdk_nvmf_tcp_req *tcp_req;
330 
331 	tcp_req = TAILQ_FIRST(&tqpair->state_queue[TCP_REQUEST_STATE_FREE]);
332 	if (!tcp_req) {
333 		return NULL;
334 	}
335 
336 	memset(&tcp_req->rsp, 0, sizeof(tcp_req->rsp));
337 	tcp_req->h2c_offset = 0;
338 	tcp_req->has_incapsule_data = false;
339 	tcp_req->req.dif.dif_insert_or_strip = false;
340 
341 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEW);
342 	return tcp_req;
343 }
344 
345 static void
346 nvmf_tcp_request_free(struct spdk_nvmf_tcp_req *tcp_req)
347 {
348 	struct spdk_nvmf_tcp_transport *ttransport;
349 
350 	assert(tcp_req != NULL);
351 
352 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tcp_req=%p will be freed\n", tcp_req);
353 	ttransport = SPDK_CONTAINEROF(tcp_req->req.qpair->transport,
354 				      struct spdk_nvmf_tcp_transport, transport);
355 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
356 	spdk_nvmf_tcp_req_process(ttransport, tcp_req);
357 }
358 
359 static int
360 spdk_nvmf_tcp_req_free(struct spdk_nvmf_request *req)
361 {
362 	struct spdk_nvmf_tcp_req *tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
363 
364 	nvmf_tcp_request_free(tcp_req);
365 
366 	return 0;
367 }
368 
369 static void
370 spdk_nvmf_tcp_drain_state_queue(struct spdk_nvmf_tcp_qpair *tqpair,
371 				enum spdk_nvmf_tcp_req_state state)
372 {
373 	struct spdk_nvmf_tcp_req *tcp_req, *req_tmp;
374 
375 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->state_queue[state], state_link, req_tmp) {
376 		nvmf_tcp_request_free(tcp_req);
377 	}
378 }
379 
380 static void
381 spdk_nvmf_tcp_cleanup_all_states(struct spdk_nvmf_tcp_qpair *tqpair)
382 {
383 	struct spdk_nvmf_tcp_req *tcp_req, *req_tmp;
384 
385 	assert(TAILQ_EMPTY(&tqpair->send_queue));
386 
387 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST);
388 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_NEW);
389 
390 	/* Wipe the requests waiting for buffer from the global list */
391 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->state_queue[TCP_REQUEST_STATE_NEED_BUFFER], state_link,
392 			   req_tmp) {
393 		STAILQ_REMOVE(&tqpair->group->group.pending_buf_queue, &tcp_req->req,
394 			      spdk_nvmf_request, buf_link);
395 	}
396 
397 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_NEED_BUFFER);
398 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_EXECUTING);
399 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
400 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_AWAITING_R2T_ACK);
401 }
402 
403 static void
404 nvmf_tcp_dump_qpair_req_contents(struct spdk_nvmf_tcp_qpair *tqpair)
405 {
406 	int i;
407 	struct spdk_nvmf_tcp_req *tcp_req;
408 
409 	SPDK_ERRLOG("Dumping contents of queue pair (QID %d)\n", tqpair->qpair.qid);
410 	for (i = 1; i < TCP_REQUEST_NUM_STATES; i++) {
411 		SPDK_ERRLOG("\tNum of requests in state[%d] = %u\n", i, tqpair->state_cntr[i]);
412 		TAILQ_FOREACH(tcp_req, &tqpair->state_queue[i], state_link) {
413 			SPDK_ERRLOG("\t\tRequest Data From Pool: %d\n", tcp_req->req.data_from_pool);
414 			SPDK_ERRLOG("\t\tRequest opcode: %d\n", tcp_req->req.cmd->nvmf_cmd.opcode);
415 		}
416 	}
417 }
418 
419 static void
420 spdk_nvmf_tcp_qpair_destroy(struct spdk_nvmf_tcp_qpair *tqpair)
421 {
422 	int err = 0;
423 
424 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
425 
426 	err = spdk_sock_close(&tqpair->sock);
427 	assert(err == 0);
428 	spdk_nvmf_tcp_cleanup_all_states(tqpair);
429 
430 	if (tqpair->state_cntr[TCP_REQUEST_STATE_FREE] != tqpair->resource_count) {
431 		SPDK_ERRLOG("tqpair(%p) free tcp request num is %u but should be %u\n", tqpair,
432 			    tqpair->state_cntr[TCP_REQUEST_STATE_FREE],
433 			    tqpair->resource_count);
434 		err++;
435 	}
436 
437 	if (err > 0) {
438 		nvmf_tcp_dump_qpair_req_contents(tqpair);
439 	}
440 
441 	spdk_dma_free(tqpair->pdus);
442 	free(tqpair->reqs);
443 	spdk_free(tqpair->bufs);
444 	free(tqpair->pdu_recv_buf.buf);
445 	free(tqpair);
446 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Leave\n");
447 }
448 
449 static int
450 spdk_nvmf_tcp_destroy(struct spdk_nvmf_transport *transport)
451 {
452 	struct spdk_nvmf_tcp_transport	*ttransport;
453 
454 	assert(transport != NULL);
455 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
456 
457 	pthread_mutex_destroy(&ttransport->lock);
458 	free(ttransport);
459 	return 0;
460 }
461 
462 static struct spdk_nvmf_transport *
463 spdk_nvmf_tcp_create(struct spdk_nvmf_transport_opts *opts)
464 {
465 	struct spdk_nvmf_tcp_transport *ttransport;
466 	uint32_t sge_count;
467 	uint32_t min_shared_buffers;
468 
469 	ttransport = calloc(1, sizeof(*ttransport));
470 	if (!ttransport) {
471 		return NULL;
472 	}
473 
474 	TAILQ_INIT(&ttransport->ports);
475 
476 	ttransport->transport.ops = &spdk_nvmf_transport_tcp;
477 
478 	SPDK_NOTICELOG("*** TCP Transport Init ***\n");
479 
480 	SPDK_INFOLOG(SPDK_LOG_NVMF_TCP, "*** TCP Transport Init ***\n"
481 		     "  Transport opts:  max_ioq_depth=%d, max_io_size=%d,\n"
482 		     "  max_qpairs_per_ctrlr=%d, io_unit_size=%d,\n"
483 		     "  in_capsule_data_size=%d, max_aq_depth=%d\n"
484 		     "  num_shared_buffers=%d, c2h_success=%d,\n"
485 		     "  dif_insert_or_strip=%d, sock_priority=%d\n",
486 		     opts->max_queue_depth,
487 		     opts->max_io_size,
488 		     opts->max_qpairs_per_ctrlr,
489 		     opts->io_unit_size,
490 		     opts->in_capsule_data_size,
491 		     opts->max_aq_depth,
492 		     opts->num_shared_buffers,
493 		     opts->c2h_success,
494 		     opts->dif_insert_or_strip,
495 		     opts->sock_priority);
496 
497 	if (opts->sock_priority > SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY) {
498 		SPDK_ERRLOG("Unsupported socket_priority=%d, the current range is: 0 to %d\n"
499 			    "you can use man 7 socket to view the range of priority under SO_PRIORITY item\n",
500 			    opts->sock_priority, SPDK_NVMF_TCP_DEFAULT_MAX_SOCK_PRIORITY);
501 		free(ttransport);
502 		return NULL;
503 	}
504 
505 	/* I/O unit size cannot be larger than max I/O size */
506 	if (opts->io_unit_size > opts->max_io_size) {
507 		opts->io_unit_size = opts->max_io_size;
508 	}
509 
510 	sge_count = opts->max_io_size / opts->io_unit_size;
511 	if (sge_count > SPDK_NVMF_MAX_SGL_ENTRIES) {
512 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", opts->io_unit_size);
513 		free(ttransport);
514 		return NULL;
515 	}
516 
517 	min_shared_buffers = spdk_thread_get_count() * opts->buf_cache_size;
518 	if (min_shared_buffers > opts->num_shared_buffers) {
519 		SPDK_ERRLOG("There are not enough buffers to satisfy"
520 			    "per-poll group caches for each thread. (%" PRIu32 ")"
521 			    "supplied. (%" PRIu32 ") required\n", opts->num_shared_buffers, min_shared_buffers);
522 		SPDK_ERRLOG("Please specify a larger number of shared buffers\n");
523 		spdk_nvmf_tcp_destroy(&ttransport->transport);
524 		return NULL;
525 	}
526 
527 	pthread_mutex_init(&ttransport->lock, NULL);
528 
529 	return &ttransport->transport;
530 }
531 
532 static int
533 _spdk_nvmf_tcp_trsvcid_to_int(const char *trsvcid)
534 {
535 	unsigned long long ull;
536 	char *end = NULL;
537 
538 	ull = strtoull(trsvcid, &end, 10);
539 	if (end == NULL || end == trsvcid || *end != '\0') {
540 		return -1;
541 	}
542 
543 	/* Valid TCP/IP port numbers are in [0, 65535] */
544 	if (ull > 65535) {
545 		return -1;
546 	}
547 
548 	return (int)ull;
549 }
550 
551 /**
552  * Canonicalize a listen address trid.
553  */
554 static int
555 _spdk_nvmf_tcp_canon_listen_trid(struct spdk_nvme_transport_id *canon_trid,
556 				 const struct spdk_nvme_transport_id *trid)
557 {
558 	int trsvcid_int;
559 
560 	trsvcid_int = _spdk_nvmf_tcp_trsvcid_to_int(trid->trsvcid);
561 	if (trsvcid_int < 0) {
562 		return -EINVAL;
563 	}
564 
565 	memset(canon_trid, 0, sizeof(*canon_trid));
566 	spdk_nvme_trid_populate_transport(canon_trid, SPDK_NVME_TRANSPORT_TCP);
567 	canon_trid->adrfam = trid->adrfam;
568 	snprintf(canon_trid->traddr, sizeof(canon_trid->traddr), "%s", trid->traddr);
569 	snprintf(canon_trid->trsvcid, sizeof(canon_trid->trsvcid), "%d", trsvcid_int);
570 
571 	return 0;
572 }
573 
574 /**
575  * Find an existing listening port.
576  *
577  * Caller must hold ttransport->lock.
578  */
579 static struct spdk_nvmf_tcp_port *
580 _spdk_nvmf_tcp_find_port(struct spdk_nvmf_tcp_transport *ttransport,
581 			 const struct spdk_nvme_transport_id *trid)
582 {
583 	struct spdk_nvme_transport_id canon_trid;
584 	struct spdk_nvmf_tcp_port *port;
585 
586 	if (_spdk_nvmf_tcp_canon_listen_trid(&canon_trid, trid) != 0) {
587 		return NULL;
588 	}
589 
590 	TAILQ_FOREACH(port, &ttransport->ports, link) {
591 		if (spdk_nvme_transport_id_compare(&canon_trid, &port->trid) == 0) {
592 			return port;
593 		}
594 	}
595 
596 	return NULL;
597 }
598 
599 static int
600 spdk_nvmf_tcp_listen(struct spdk_nvmf_transport *transport,
601 		     const struct spdk_nvme_transport_id *trid,
602 		     spdk_nvmf_tgt_listen_done_fn cb_fn,
603 		     void *cb_arg)
604 {
605 	struct spdk_nvmf_tcp_transport *ttransport;
606 	struct spdk_nvmf_tcp_port *port;
607 	int trsvcid_int;
608 	uint8_t adrfam;
609 
610 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
611 
612 	trsvcid_int = _spdk_nvmf_tcp_trsvcid_to_int(trid->trsvcid);
613 	if (trsvcid_int < 0) {
614 		SPDK_ERRLOG("Invalid trsvcid '%s'\n", trid->trsvcid);
615 		return -EINVAL;
616 	}
617 
618 	pthread_mutex_lock(&ttransport->lock);
619 	port = _spdk_nvmf_tcp_find_port(ttransport, trid);
620 	if (port) {
621 		goto success;
622 	}
623 
624 	port = calloc(1, sizeof(*port));
625 	if (!port) {
626 		SPDK_ERRLOG("Port allocation failed\n");
627 		pthread_mutex_unlock(&ttransport->lock);
628 		return -ENOMEM;
629 	}
630 
631 	if (_spdk_nvmf_tcp_canon_listen_trid(&port->trid, trid) != 0) {
632 		SPDK_ERRLOG("Invalid traddr %s / trsvcid %s\n",
633 			    trid->traddr, trid->trsvcid);
634 		free(port);
635 		pthread_mutex_unlock(&ttransport->lock);
636 		return -ENOMEM;
637 	}
638 
639 	port->listen_sock = spdk_sock_listen(trid->traddr, trsvcid_int, NULL);
640 	if (port->listen_sock == NULL) {
641 		SPDK_ERRLOG("spdk_sock_listen(%s, %d) failed: %s (%d)\n",
642 			    trid->traddr, trsvcid_int,
643 			    spdk_strerror(errno), errno);
644 		free(port);
645 		pthread_mutex_unlock(&ttransport->lock);
646 		return -errno;
647 	}
648 
649 	if (spdk_sock_is_ipv4(port->listen_sock)) {
650 		adrfam = SPDK_NVMF_ADRFAM_IPV4;
651 	} else if (spdk_sock_is_ipv6(port->listen_sock)) {
652 		adrfam = SPDK_NVMF_ADRFAM_IPV6;
653 	} else {
654 		SPDK_ERRLOG("Unhandled socket type\n");
655 		adrfam = 0;
656 	}
657 
658 	if (adrfam != trid->adrfam) {
659 		SPDK_ERRLOG("Socket address family mismatch\n");
660 		spdk_sock_close(&port->listen_sock);
661 		free(port);
662 		pthread_mutex_unlock(&ttransport->lock);
663 		return -EINVAL;
664 	}
665 
666 	SPDK_NOTICELOG("*** NVMe/TCP Target Listening on %s port %s ***\n",
667 		       trid->traddr, trid->trsvcid);
668 
669 	TAILQ_INSERT_TAIL(&ttransport->ports, port, link);
670 
671 success:
672 	port->ref++;
673 	pthread_mutex_unlock(&ttransport->lock);
674 	cb_fn(cb_arg, 0);
675 	return 0;
676 }
677 
678 static int
679 spdk_nvmf_tcp_stop_listen(struct spdk_nvmf_transport *transport,
680 			  const struct spdk_nvme_transport_id *trid)
681 {
682 	struct spdk_nvmf_tcp_transport *ttransport;
683 	struct spdk_nvmf_tcp_port *port;
684 	int rc;
685 
686 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
687 
688 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Removing listen address %s port %s\n",
689 		      trid->traddr, trid->trsvcid);
690 
691 	pthread_mutex_lock(&ttransport->lock);
692 	port = _spdk_nvmf_tcp_find_port(ttransport, trid);
693 	if (port) {
694 		assert(port->ref > 0);
695 		port->ref--;
696 		if (port->ref == 0) {
697 			TAILQ_REMOVE(&ttransport->ports, port, link);
698 			spdk_sock_close(&port->listen_sock);
699 			free(port);
700 		}
701 		rc = 0;
702 	} else {
703 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Port not found\n");
704 		rc = -ENOENT;
705 	}
706 	pthread_mutex_unlock(&ttransport->lock);
707 
708 	return rc;
709 }
710 
711 static void spdk_nvmf_tcp_qpair_set_recv_state(struct spdk_nvmf_tcp_qpair *tqpair,
712 		enum nvme_tcp_pdu_recv_state state);
713 
714 static void
715 spdk_nvmf_tcp_qpair_disconnect(struct spdk_nvmf_tcp_qpair *tqpair)
716 {
717 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Disconnecting qpair %p\n", tqpair);
718 
719 	if (tqpair->state <= NVME_TCP_QPAIR_STATE_RUNNING) {
720 		tqpair->state = NVME_TCP_QPAIR_STATE_EXITING;
721 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
722 		spdk_poller_unregister(&tqpair->timeout_poller);
723 
724 		/* This will end up calling spdk_nvmf_tcp_close_qpair */
725 		spdk_nvmf_qpair_disconnect(&tqpair->qpair, NULL, NULL);
726 	}
727 }
728 
729 static void
730 _pdu_write_done(void *_pdu, int err)
731 {
732 	struct nvme_tcp_pdu			*pdu = _pdu;
733 	struct spdk_nvmf_tcp_qpair		*tqpair = pdu->qpair;
734 
735 	TAILQ_REMOVE(&tqpair->send_queue, pdu, tailq);
736 
737 	if (err != 0) {
738 		spdk_nvmf_tcp_qpair_disconnect(tqpair);
739 		return;
740 	}
741 
742 	assert(pdu->cb_fn != NULL);
743 	pdu->cb_fn(pdu->cb_arg);
744 }
745 
746 static void
747 spdk_nvmf_tcp_qpair_write_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
748 			      struct nvme_tcp_pdu *pdu,
749 			      nvme_tcp_qpair_xfer_complete_cb cb_fn,
750 			      void *cb_arg)
751 {
752 	int hlen;
753 	uint32_t crc32c;
754 	uint32_t mapped_length = 0;
755 	ssize_t rc;
756 
757 	assert(&tqpair->pdu_in_progress != pdu);
758 
759 	hlen = pdu->hdr->common.hlen;
760 
761 	/* Header Digest */
762 	if (g_nvme_tcp_hdgst[pdu->hdr->common.pdu_type] && tqpair->host_hdgst_enable) {
763 		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
764 		MAKE_DIGEST_WORD((uint8_t *)pdu->hdr->raw + hlen, crc32c);
765 	}
766 
767 	/* Data Digest */
768 	if (pdu->data_len > 0 && g_nvme_tcp_ddgst[pdu->hdr->common.pdu_type] && tqpair->host_ddgst_enable) {
769 		crc32c = nvme_tcp_pdu_calc_data_digest(pdu);
770 		MAKE_DIGEST_WORD(pdu->data_digest, crc32c);
771 	}
772 
773 	pdu->cb_fn = cb_fn;
774 	pdu->cb_arg = cb_arg;
775 
776 	pdu->sock_req.iovcnt = nvme_tcp_build_iovs(pdu->iov, SPDK_COUNTOF(pdu->iov), pdu,
777 			       tqpair->host_hdgst_enable, tqpair->host_ddgst_enable,
778 			       &mapped_length);
779 	pdu->sock_req.cb_fn = _pdu_write_done;
780 	pdu->sock_req.cb_arg = pdu;
781 	TAILQ_INSERT_TAIL(&tqpair->send_queue, pdu, tailq);
782 	if (pdu->hdr->common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_RESP ||
783 	    pdu->hdr->common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ) {
784 		rc = spdk_sock_writev(tqpair->sock, pdu->iov, pdu->sock_req.iovcnt);
785 		if (rc == mapped_length) {
786 			_pdu_write_done(pdu, 0);
787 		} else {
788 			SPDK_ERRLOG("IC_RESP or TERM_REQ could not write to socket.\n");
789 			_pdu_write_done(pdu, -1);
790 		}
791 	} else {
792 		spdk_sock_writev_async(tqpair->sock, &pdu->sock_req);
793 	}
794 }
795 
796 static int
797 spdk_nvmf_tcp_qpair_init_mem_resource(struct spdk_nvmf_tcp_qpair *tqpair)
798 {
799 	uint32_t i;
800 	struct spdk_nvmf_transport_opts *opts;
801 	uint32_t in_capsule_data_size;
802 
803 	opts = &tqpair->qpair.transport->opts;
804 
805 	in_capsule_data_size = opts->in_capsule_data_size;
806 	if (opts->dif_insert_or_strip) {
807 		in_capsule_data_size = SPDK_BDEV_BUF_SIZE_WITH_MD(in_capsule_data_size);
808 	}
809 
810 	tqpair->resource_count = opts->max_queue_depth;
811 
812 	tqpair->mgmt_pdu.qpair = tqpair;
813 	tqpair->mgmt_pdu.hdr = &tqpair->mgmt_pdu.hdr_mem;
814 
815 	tqpair->reqs = calloc(tqpair->resource_count, sizeof(*tqpair->reqs));
816 	if (!tqpair->reqs) {
817 		SPDK_ERRLOG("Unable to allocate reqs on tqpair=%p\n", tqpair);
818 		return -1;
819 	}
820 
821 	if (in_capsule_data_size) {
822 		tqpair->bufs = spdk_zmalloc(tqpair->resource_count * in_capsule_data_size, 0x1000,
823 					    NULL, SPDK_ENV_LCORE_ID_ANY,
824 					    SPDK_MALLOC_DMA);
825 		if (!tqpair->bufs) {
826 			SPDK_ERRLOG("Unable to allocate bufs on tqpair=%p.\n", tqpair);
827 			return -1;
828 		}
829 	}
830 
831 	tqpair->pdus = spdk_dma_malloc(tqpair->resource_count * sizeof(*tqpair->pdus), 0x1000, NULL);
832 	if (!tqpair->pdus) {
833 		SPDK_ERRLOG("Unable to allocate pdu pool on tqpair =%p.\n", tqpair);
834 		return -1;
835 	}
836 
837 	for (i = 0; i < tqpair->resource_count; i++) {
838 		struct spdk_nvmf_tcp_req *tcp_req = &tqpair->reqs[i];
839 
840 		tcp_req->ttag = i + 1;
841 		tcp_req->req.qpair = &tqpair->qpair;
842 
843 		tcp_req->pdu = &tqpair->pdus[i];
844 		tcp_req->pdu->qpair = tqpair;
845 		tcp_req->pdu->hdr = &tcp_req->pdu->hdr_mem;
846 
847 		/* Set up memory to receive commands */
848 		if (tqpair->bufs) {
849 			tcp_req->buf = (void *)((uintptr_t)tqpair->bufs + (i * in_capsule_data_size));
850 		}
851 
852 		/* Set the cmdn and rsp */
853 		tcp_req->req.rsp = (union nvmf_c2h_msg *)&tcp_req->rsp;
854 		tcp_req->req.cmd = (union nvmf_h2c_msg *)&tcp_req->cmd;
855 
856 		/* Initialize request state to FREE */
857 		tcp_req->state = TCP_REQUEST_STATE_FREE;
858 		TAILQ_INSERT_TAIL(&tqpair->state_queue[tcp_req->state], tcp_req, state_link);
859 		tqpair->state_cntr[TCP_REQUEST_STATE_FREE]++;
860 	}
861 
862 	tqpair->pdu_recv_buf.size = (in_capsule_data_size + sizeof(struct spdk_nvme_tcp_cmd) + 2 *
863 				     SPDK_NVME_TCP_DIGEST_LEN) * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
864 	tqpair->pdu_recv_buf.buf = calloc(1, tqpair->pdu_recv_buf.size);
865 	if (!tqpair->pdu_recv_buf.buf) {
866 		SPDK_ERRLOG("Unable to allocate the pdu recv buf on tqpair=%p with size=%d\n", tqpair,
867 			    tqpair->pdu_recv_buf.size);
868 		return -1;
869 	}
870 	tqpair->pdu_in_progress.hdr = (union nvme_tcp_pdu_hdr *)tqpair->pdu_recv_buf.buf;
871 
872 	return 0;
873 }
874 
875 static int
876 spdk_nvmf_tcp_qpair_init(struct spdk_nvmf_qpair *qpair)
877 {
878 	struct spdk_nvmf_tcp_qpair *tqpair;
879 	int i;
880 
881 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
882 
883 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "New TCP Connection: %p\n", qpair);
884 
885 	TAILQ_INIT(&tqpair->send_queue);
886 
887 	/* Initialise request state queues of the qpair */
888 	for (i = TCP_REQUEST_STATE_FREE; i < TCP_REQUEST_NUM_STATES; i++) {
889 		TAILQ_INIT(&tqpair->state_queue[i]);
890 	}
891 
892 	tqpair->host_hdgst_enable = true;
893 	tqpair->host_ddgst_enable = true;
894 	return 0;
895 }
896 
897 static int
898 spdk_nvmf_tcp_qpair_sock_init(struct spdk_nvmf_tcp_qpair *tqpair)
899 {
900 	int rc;
901 
902 	/* set low water mark */
903 	rc = spdk_sock_set_recvlowat(tqpair->sock, sizeof(struct spdk_nvme_tcp_c2h_data_hdr));
904 	if (rc != 0) {
905 		SPDK_ERRLOG("spdk_sock_set_recvlowat() failed\n");
906 		return rc;
907 	}
908 
909 	return 0;
910 }
911 
912 static void
913 _spdk_nvmf_tcp_handle_connect(struct spdk_nvmf_transport *transport,
914 			      struct spdk_nvmf_tcp_port *port,
915 			      struct spdk_sock *sock,
916 			      new_qpair_fn cb_fn, void *cb_arg)
917 {
918 	struct spdk_nvmf_tcp_qpair *tqpair;
919 	int rc;
920 
921 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "New connection accepted on %s port %s\n",
922 		      port->trid.traddr, port->trid.trsvcid);
923 
924 	if (transport->opts.sock_priority) {
925 		rc = spdk_sock_set_priority(sock, transport->opts.sock_priority);
926 		if (rc) {
927 			SPDK_ERRLOG("Failed to set the priority of the socket\n");
928 			spdk_sock_close(&sock);
929 			return;
930 		}
931 	}
932 
933 	tqpair = calloc(1, sizeof(struct spdk_nvmf_tcp_qpair));
934 	if (tqpair == NULL) {
935 		SPDK_ERRLOG("Could not allocate new connection.\n");
936 		spdk_sock_close(&sock);
937 		return;
938 	}
939 
940 	tqpair->sock = sock;
941 	tqpair->state_cntr[TCP_REQUEST_STATE_FREE] = 0;
942 	tqpair->port = port;
943 	tqpair->qpair.transport = transport;
944 
945 	rc = spdk_sock_getaddr(tqpair->sock, tqpair->target_addr,
946 			       sizeof(tqpair->target_addr), &tqpair->target_port,
947 			       tqpair->initiator_addr, sizeof(tqpair->initiator_addr),
948 			       &tqpair->initiator_port);
949 	if (rc < 0) {
950 		SPDK_ERRLOG("spdk_sock_getaddr() failed of tqpair=%p\n", tqpair);
951 		spdk_nvmf_tcp_qpair_destroy(tqpair);
952 		return;
953 	}
954 
955 	cb_fn(&tqpair->qpair, cb_arg);
956 }
957 
958 static void
959 spdk_nvmf_tcp_port_accept(struct spdk_nvmf_transport *transport, struct spdk_nvmf_tcp_port *port,
960 			  new_qpair_fn cb_fn, void *cb_arg)
961 {
962 	struct spdk_sock *sock;
963 	int i;
964 
965 	for (i = 0; i < NVMF_TCP_MAX_ACCEPT_SOCK_ONE_TIME; i++) {
966 		sock = spdk_sock_accept(port->listen_sock);
967 		if (sock == NULL) {
968 			break;
969 		}
970 		_spdk_nvmf_tcp_handle_connect(transport, port, sock, cb_fn, cb_arg);
971 	}
972 }
973 
974 static void
975 spdk_nvmf_tcp_accept(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn, void *cb_arg)
976 {
977 	struct spdk_nvmf_tcp_transport *ttransport;
978 	struct spdk_nvmf_tcp_port *port;
979 
980 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
981 
982 	TAILQ_FOREACH(port, &ttransport->ports, link) {
983 		spdk_nvmf_tcp_port_accept(transport, port, cb_fn, cb_arg);
984 	}
985 }
986 
987 static void
988 spdk_nvmf_tcp_discover(struct spdk_nvmf_transport *transport,
989 		       struct spdk_nvme_transport_id *trid,
990 		       struct spdk_nvmf_discovery_log_page_entry *entry)
991 {
992 	entry->trtype = SPDK_NVMF_TRTYPE_TCP;
993 	entry->adrfam = trid->adrfam;
994 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_REQUIRED;
995 
996 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
997 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
998 
999 	entry->tsas.tcp.sectype = SPDK_NVME_TCP_SECURITY_NONE;
1000 }
1001 
1002 static struct spdk_nvmf_transport_poll_group *
1003 spdk_nvmf_tcp_poll_group_create(struct spdk_nvmf_transport *transport)
1004 {
1005 	struct spdk_nvmf_tcp_poll_group *tgroup;
1006 
1007 	tgroup = calloc(1, sizeof(*tgroup));
1008 	if (!tgroup) {
1009 		return NULL;
1010 	}
1011 
1012 	tgroup->sock_group = spdk_sock_group_create(&tgroup->group);
1013 	if (!tgroup->sock_group) {
1014 		goto cleanup;
1015 	}
1016 
1017 	TAILQ_INIT(&tgroup->qpairs);
1018 	TAILQ_INIT(&tgroup->await_req);
1019 
1020 	return &tgroup->group;
1021 
1022 cleanup:
1023 	free(tgroup);
1024 	return NULL;
1025 }
1026 
1027 static struct spdk_nvmf_transport_poll_group *
1028 spdk_nvmf_tcp_get_optimal_poll_group(struct spdk_nvmf_qpair *qpair)
1029 {
1030 	struct spdk_nvmf_tcp_qpair *tqpair;
1031 	struct spdk_sock_group *group = NULL;
1032 	int rc;
1033 
1034 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
1035 	rc = spdk_sock_get_optimal_sock_group(tqpair->sock, &group);
1036 	if (!rc && group != NULL) {
1037 		return spdk_sock_group_get_ctx(group);
1038 	}
1039 
1040 	return NULL;
1041 }
1042 
1043 static void
1044 spdk_nvmf_tcp_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
1045 {
1046 	struct spdk_nvmf_tcp_poll_group *tgroup;
1047 
1048 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
1049 	spdk_sock_group_close(&tgroup->sock_group);
1050 
1051 	free(tgroup);
1052 }
1053 
1054 static inline void
1055 spdk_nvmf_tcp_reset_pdu_in_process(struct spdk_nvmf_tcp_qpair *tqpair)
1056 {
1057 	struct nvme_tcp_pdu_recv_buf *pdu_recv_buf = &tqpair->pdu_recv_buf;
1058 	char *dst, *src;
1059 
1060 	if (spdk_unlikely((pdu_recv_buf->off + sizeof(union nvme_tcp_pdu_hdr)) >
1061 			  pdu_recv_buf->size)) {
1062 		if (pdu_recv_buf->remain_size) {
1063 			dst = pdu_recv_buf->buf;
1064 			src = (char *)((void *)pdu_recv_buf->buf + pdu_recv_buf->off);
1065 
1066 			/* purpose: to avoid overlap copy, so do not use memcpy if there is overlap case */
1067 			memmove(dst, src, pdu_recv_buf->remain_size);
1068 		}
1069 		tqpair->pdu_recv_buf.off = 0;
1070 	} else if (!pdu_recv_buf->remain_size) {
1071 		tqpair->pdu_recv_buf.off = 0;
1072 	}
1073 
1074 	tqpair->pdu_in_progress.hdr = (union nvme_tcp_pdu_hdr *)((void *)pdu_recv_buf->buf +
1075 				      pdu_recv_buf->off);
1076 }
1077 
1078 static void
1079 spdk_nvmf_tcp_qpair_set_recv_state(struct spdk_nvmf_tcp_qpair *tqpair,
1080 				   enum nvme_tcp_pdu_recv_state state)
1081 {
1082 	if (tqpair->recv_state == state) {
1083 		SPDK_ERRLOG("The recv state of tqpair=%p is same with the state(%d) to be set\n",
1084 			    tqpair, state);
1085 		return;
1086 	}
1087 
1088 	if (tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_REQ) {
1089 		/* When leaving the await req state, move the qpair to the main list */
1090 		TAILQ_REMOVE(&tqpair->group->await_req, tqpair, link);
1091 		TAILQ_INSERT_TAIL(&tqpair->group->qpairs, tqpair, link);
1092 	}
1093 
1094 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tqpair(%p) recv state=%d\n", tqpair, state);
1095 	tqpair->recv_state = state;
1096 
1097 	switch (state) {
1098 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH:
1099 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH:
1100 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:
1101 		break;
1102 	case NVME_TCP_PDU_RECV_STATE_AWAIT_REQ:
1103 		TAILQ_REMOVE(&tqpair->group->qpairs, tqpair, link);
1104 		TAILQ_INSERT_TAIL(&tqpair->group->await_req, tqpair, link);
1105 		break;
1106 	case NVME_TCP_PDU_RECV_STATE_ERROR:
1107 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY:
1108 		memset(&tqpair->pdu_in_progress, 0, sizeof(tqpair->pdu_in_progress));
1109 		spdk_nvmf_tcp_reset_pdu_in_process(tqpair);
1110 		break;
1111 	default:
1112 		SPDK_ERRLOG("The state(%d) is invalid\n", state);
1113 		abort();
1114 		break;
1115 	}
1116 }
1117 
1118 static int
1119 spdk_nvmf_tcp_qpair_handle_timeout(void *ctx)
1120 {
1121 	struct spdk_nvmf_tcp_qpair *tqpair = ctx;
1122 
1123 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_ERROR);
1124 
1125 	SPDK_ERRLOG("No pdu coming for tqpair=%p within %d seconds\n", tqpair,
1126 		    SPDK_NVME_TCP_QPAIR_EXIT_TIMEOUT);
1127 
1128 	spdk_nvmf_tcp_qpair_disconnect(tqpair);
1129 	return 0;
1130 }
1131 
1132 static void
1133 spdk_nvmf_tcp_send_c2h_term_req_complete(void *cb_arg)
1134 {
1135 	struct spdk_nvmf_tcp_qpair *tqpair = (struct spdk_nvmf_tcp_qpair *)cb_arg;
1136 
1137 	if (!tqpair->timeout_poller) {
1138 		tqpair->timeout_poller = spdk_poller_register(spdk_nvmf_tcp_qpair_handle_timeout, tqpair,
1139 					 SPDK_NVME_TCP_QPAIR_EXIT_TIMEOUT * 1000000);
1140 	}
1141 }
1142 
1143 static void
1144 spdk_nvmf_tcp_send_c2h_term_req(struct spdk_nvmf_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu,
1145 				enum spdk_nvme_tcp_term_req_fes fes, uint32_t error_offset)
1146 {
1147 	struct nvme_tcp_pdu *rsp_pdu;
1148 	struct spdk_nvme_tcp_term_req_hdr *c2h_term_req;
1149 	uint32_t c2h_term_req_hdr_len = sizeof(*c2h_term_req);
1150 	uint32_t copy_len;
1151 
1152 	rsp_pdu = &tqpair->mgmt_pdu;
1153 
1154 	c2h_term_req = &rsp_pdu->hdr->term_req;
1155 	c2h_term_req->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ;
1156 	c2h_term_req->common.hlen = c2h_term_req_hdr_len;
1157 
1158 	if ((fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
1159 	    (fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
1160 		DSET32(&c2h_term_req->fei, error_offset);
1161 	}
1162 
1163 	copy_len = spdk_min(pdu->hdr->common.hlen, SPDK_NVME_TCP_TERM_REQ_ERROR_DATA_MAX_SIZE);
1164 
1165 	/* Copy the error info into the buffer */
1166 	memcpy((uint8_t *)rsp_pdu->hdr->raw + c2h_term_req_hdr_len, pdu->hdr->raw, copy_len);
1167 	nvme_tcp_pdu_set_data(rsp_pdu, (uint8_t *)rsp_pdu->hdr->raw + c2h_term_req_hdr_len, copy_len);
1168 
1169 	/* Contain the header of the wrong received pdu */
1170 	c2h_term_req->common.plen = c2h_term_req->common.hlen + copy_len;
1171 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1172 	spdk_nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, spdk_nvmf_tcp_send_c2h_term_req_complete, tqpair);
1173 }
1174 
1175 static void
1176 spdk_nvmf_tcp_capsule_cmd_hdr_handle(struct spdk_nvmf_tcp_transport *ttransport,
1177 				     struct spdk_nvmf_tcp_qpair *tqpair,
1178 				     struct nvme_tcp_pdu *pdu)
1179 {
1180 	struct spdk_nvmf_tcp_req *tcp_req;
1181 
1182 	assert(pdu->psh_valid_bytes == pdu->psh_len);
1183 	assert(pdu->hdr->common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD);
1184 
1185 	tcp_req = spdk_nvmf_tcp_req_get(tqpair);
1186 	if (!tcp_req) {
1187 		/* Directly return and make the allocation retry again */
1188 		if (tqpair->state_cntr[TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST] > 0) {
1189 			return;
1190 		}
1191 
1192 		/* The host sent more commands than the maximum queue depth. */
1193 		SPDK_ERRLOG("Cannot allocate tcp_req on tqpair=%p\n", tqpair);
1194 		spdk_nvmf_tcp_qpair_disconnect(tqpair);
1195 		return;
1196 	}
1197 
1198 	pdu->req = tcp_req;
1199 	assert(tcp_req->state == TCP_REQUEST_STATE_NEW);
1200 	spdk_nvmf_tcp_req_process(ttransport, tcp_req);
1201 }
1202 
1203 static void
1204 spdk_nvmf_tcp_capsule_cmd_payload_handle(struct spdk_nvmf_tcp_transport *ttransport,
1205 		struct spdk_nvmf_tcp_qpair *tqpair,
1206 		struct nvme_tcp_pdu *pdu)
1207 {
1208 	struct spdk_nvmf_tcp_req *tcp_req;
1209 	struct spdk_nvme_tcp_cmd *capsule_cmd;
1210 	uint32_t error_offset = 0;
1211 	enum spdk_nvme_tcp_term_req_fes fes;
1212 
1213 	capsule_cmd = &pdu->hdr->capsule_cmd;
1214 	tcp_req = pdu->req;
1215 	assert(tcp_req != NULL);
1216 	if (capsule_cmd->common.pdo > SPDK_NVME_TCP_PDU_PDO_MAX_OFFSET) {
1217 		SPDK_ERRLOG("Expected ICReq capsule_cmd pdu offset <= %d, got %c\n",
1218 			    SPDK_NVME_TCP_PDU_PDO_MAX_OFFSET, capsule_cmd->common.pdo);
1219 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1220 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdo);
1221 		goto err;
1222 	}
1223 
1224 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1225 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1226 	spdk_nvmf_tcp_req_process(ttransport, tcp_req);
1227 
1228 	return;
1229 err:
1230 	spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1231 }
1232 
1233 static int
1234 nvmf_tcp_find_req_in_state(struct spdk_nvmf_tcp_qpair *tqpair,
1235 			   enum spdk_nvmf_tcp_req_state state,
1236 			   uint16_t cid, uint16_t tag,
1237 			   struct spdk_nvmf_tcp_req **req)
1238 {
1239 	struct spdk_nvmf_tcp_req *tcp_req = NULL;
1240 
1241 	TAILQ_FOREACH(tcp_req, &tqpair->state_queue[state], state_link) {
1242 		if (tcp_req->req.cmd->nvme_cmd.cid != cid) {
1243 			continue;
1244 		}
1245 
1246 		if (tcp_req->ttag == tag) {
1247 			*req = tcp_req;
1248 			return 0;
1249 		}
1250 
1251 		*req = NULL;
1252 		return -1;
1253 	}
1254 
1255 	/* Didn't find it, but not an error */
1256 	*req = NULL;
1257 	return 0;
1258 }
1259 
1260 static void
1261 spdk_nvmf_tcp_h2c_data_hdr_handle(struct spdk_nvmf_tcp_transport *ttransport,
1262 				  struct spdk_nvmf_tcp_qpair *tqpair,
1263 				  struct nvme_tcp_pdu *pdu)
1264 {
1265 	struct spdk_nvmf_tcp_req *tcp_req;
1266 	uint32_t error_offset = 0;
1267 	enum spdk_nvme_tcp_term_req_fes fes = 0;
1268 	struct spdk_nvme_tcp_h2c_data_hdr *h2c_data;
1269 	int rc;
1270 
1271 	h2c_data = &pdu->hdr->h2c_data;
1272 
1273 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tqpair=%p, r2t_info: datao=%u, datal=%u, cccid=%u, ttag=%u\n",
1274 		      tqpair, h2c_data->datao, h2c_data->datal, h2c_data->cccid, h2c_data->ttag);
1275 
1276 	rc = nvmf_tcp_find_req_in_state(tqpair, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
1277 					h2c_data->cccid, h2c_data->ttag, &tcp_req);
1278 	if (rc == 0 && tcp_req == NULL) {
1279 		rc = nvmf_tcp_find_req_in_state(tqpair, TCP_REQUEST_STATE_AWAITING_R2T_ACK, h2c_data->cccid,
1280 						h2c_data->ttag, &tcp_req);
1281 	}
1282 
1283 	if (!tcp_req) {
1284 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tcp_req is not found for tqpair=%p\n", tqpair);
1285 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER;
1286 		if (rc == 0) {
1287 			error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, cccid);
1288 		} else {
1289 			error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, ttag);
1290 		}
1291 		goto err;
1292 	}
1293 
1294 	if (tcp_req->h2c_offset != h2c_data->datao) {
1295 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP,
1296 			      "tcp_req(%p), tqpair=%p, expected data offset %u, but data offset is %u\n",
1297 			      tcp_req, tqpair, tcp_req->h2c_offset, h2c_data->datao);
1298 		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
1299 		goto err;
1300 	}
1301 
1302 	if ((h2c_data->datao + h2c_data->datal) > tcp_req->req.length) {
1303 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP,
1304 			      "tcp_req(%p), tqpair=%p,  (datao=%u + datal=%u) execeeds requested length=%u\n",
1305 			      tcp_req, tqpair, h2c_data->datao, h2c_data->datal, tcp_req->req.length);
1306 		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
1307 		goto err;
1308 	}
1309 
1310 	pdu->req = tcp_req;
1311 
1312 	if (spdk_unlikely(tcp_req->req.dif.dif_insert_or_strip)) {
1313 		pdu->dif_ctx = &tcp_req->req.dif.dif_ctx;
1314 	}
1315 
1316 	nvme_tcp_pdu_set_data_buf(pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
1317 				  h2c_data->datao, h2c_data->datal);
1318 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1319 	return;
1320 
1321 err:
1322 	spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1323 }
1324 
1325 static void
1326 spdk_nvmf_tcp_pdu_cmd_complete(void *cb_arg)
1327 {
1328 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
1329 	nvmf_tcp_request_free(tcp_req);
1330 }
1331 
1332 static void
1333 spdk_nvmf_tcp_send_capsule_resp_pdu(struct spdk_nvmf_tcp_req *tcp_req,
1334 				    struct spdk_nvmf_tcp_qpair *tqpair)
1335 {
1336 	struct nvme_tcp_pdu *rsp_pdu;
1337 	struct spdk_nvme_tcp_rsp *capsule_resp;
1338 
1339 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter, tqpair=%p\n", tqpair);
1340 
1341 	rsp_pdu = nvmf_tcp_req_pdu_init(tcp_req);
1342 	assert(rsp_pdu != NULL);
1343 
1344 	capsule_resp = &rsp_pdu->hdr->capsule_resp;
1345 	capsule_resp->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_CAPSULE_RESP;
1346 	capsule_resp->common.plen = capsule_resp->common.hlen = sizeof(*capsule_resp);
1347 	capsule_resp->rccqe = tcp_req->req.rsp->nvme_cpl;
1348 	if (tqpair->host_hdgst_enable) {
1349 		capsule_resp->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
1350 		capsule_resp->common.plen += SPDK_NVME_TCP_DIGEST_LEN;
1351 	}
1352 
1353 	spdk_nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, spdk_nvmf_tcp_pdu_cmd_complete, tcp_req);
1354 }
1355 
1356 static void
1357 spdk_nvmf_tcp_pdu_c2h_data_complete(void *cb_arg)
1358 {
1359 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
1360 	struct spdk_nvmf_tcp_qpair *tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair,
1361 					     struct spdk_nvmf_tcp_qpair, qpair);
1362 
1363 	assert(tqpair != NULL);
1364 	if (tqpair->qpair.transport->opts.c2h_success) {
1365 		nvmf_tcp_request_free(tcp_req);
1366 	} else {
1367 		nvmf_tcp_req_pdu_fini(tcp_req);
1368 		spdk_nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
1369 	}
1370 }
1371 
1372 static void
1373 spdk_nvmf_tcp_r2t_complete(void *cb_arg)
1374 {
1375 	struct spdk_nvmf_tcp_req *tcp_req = cb_arg;
1376 	struct spdk_nvmf_tcp_transport *ttransport;
1377 
1378 	nvmf_tcp_req_pdu_fini(tcp_req);
1379 
1380 	ttransport = SPDK_CONTAINEROF(tcp_req->req.qpair->transport,
1381 				      struct spdk_nvmf_tcp_transport, transport);
1382 
1383 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
1384 
1385 	if (tcp_req->h2c_offset == tcp_req->req.length) {
1386 		spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1387 		spdk_nvmf_tcp_req_process(ttransport, tcp_req);
1388 	}
1389 }
1390 
1391 static void
1392 spdk_nvmf_tcp_send_r2t_pdu(struct spdk_nvmf_tcp_qpair *tqpair,
1393 			   struct spdk_nvmf_tcp_req *tcp_req)
1394 {
1395 	struct nvme_tcp_pdu *rsp_pdu;
1396 	struct spdk_nvme_tcp_r2t_hdr *r2t;
1397 
1398 	rsp_pdu = nvmf_tcp_req_pdu_init(tcp_req);
1399 	assert(rsp_pdu != NULL);
1400 
1401 	r2t = &rsp_pdu->hdr->r2t;
1402 	r2t->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_R2T;
1403 	r2t->common.plen = r2t->common.hlen = sizeof(*r2t);
1404 
1405 	if (tqpair->host_hdgst_enable) {
1406 		r2t->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
1407 		r2t->common.plen += SPDK_NVME_TCP_DIGEST_LEN;
1408 	}
1409 
1410 	r2t->cccid = tcp_req->req.cmd->nvme_cmd.cid;
1411 	r2t->ttag = tcp_req->ttag;
1412 	r2t->r2to = tcp_req->h2c_offset;
1413 	r2t->r2tl = tcp_req->req.length;
1414 
1415 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_AWAITING_R2T_ACK);
1416 
1417 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP,
1418 		      "tcp_req(%p) on tqpair(%p), r2t_info: cccid=%u, ttag=%u, r2to=%u, r2tl=%u\n",
1419 		      tcp_req, tqpair, r2t->cccid, r2t->ttag, r2t->r2to, r2t->r2tl);
1420 	spdk_nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, spdk_nvmf_tcp_r2t_complete, tcp_req);
1421 }
1422 
1423 static void
1424 spdk_nvmf_tcp_h2c_data_payload_handle(struct spdk_nvmf_tcp_transport *ttransport,
1425 				      struct spdk_nvmf_tcp_qpair *tqpair,
1426 				      struct nvme_tcp_pdu *pdu)
1427 {
1428 	struct spdk_nvmf_tcp_req *tcp_req;
1429 
1430 	tcp_req = pdu->req;
1431 	assert(tcp_req != NULL);
1432 
1433 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
1434 
1435 	tcp_req->h2c_offset += pdu->data_len;
1436 
1437 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1438 
1439 	/* Wait for all of the data to arrive AND for the initial R2T PDU send to be
1440 	 * acknowledged before moving on. */
1441 	if (tcp_req->h2c_offset == tcp_req->req.length &&
1442 	    tcp_req->state == TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER) {
1443 		spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1444 		spdk_nvmf_tcp_req_process(ttransport, tcp_req);
1445 	}
1446 }
1447 
1448 static void
1449 spdk_nvmf_tcp_h2c_term_req_dump(struct spdk_nvme_tcp_term_req_hdr *h2c_term_req)
1450 {
1451 	SPDK_ERRLOG("Error info of pdu(%p): %s\n", h2c_term_req,
1452 		    spdk_nvmf_tcp_term_req_fes_str[h2c_term_req->fes]);
1453 	if ((h2c_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
1454 	    (h2c_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
1455 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "The offset from the start of the PDU header is %u\n",
1456 			      DGET32(h2c_term_req->fei));
1457 	}
1458 }
1459 
1460 static void
1461 spdk_nvmf_tcp_h2c_term_req_hdr_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1462 				      struct nvme_tcp_pdu *pdu)
1463 {
1464 	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req = &pdu->hdr->term_req;
1465 	uint32_t error_offset = 0;
1466 	enum spdk_nvme_tcp_term_req_fes fes;
1467 
1468 
1469 	if (h2c_term_req->fes > SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER) {
1470 		SPDK_ERRLOG("Fatal Error Stauts(FES) is unknown for h2c_term_req pdu=%p\n", pdu);
1471 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1472 		error_offset = offsetof(struct spdk_nvme_tcp_term_req_hdr, fes);
1473 		goto end;
1474 	}
1475 
1476 	/* set the data buffer */
1477 	nvme_tcp_pdu_set_data(pdu, (uint8_t *)pdu->hdr->raw + h2c_term_req->common.hlen,
1478 			      h2c_term_req->common.plen - h2c_term_req->common.hlen);
1479 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1480 	return;
1481 end:
1482 	spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1483 }
1484 
1485 static void
1486 spdk_nvmf_tcp_h2c_term_req_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1487 		struct nvme_tcp_pdu *pdu)
1488 {
1489 	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req = &pdu->hdr->term_req;
1490 
1491 	spdk_nvmf_tcp_h2c_term_req_dump(h2c_term_req);
1492 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1493 }
1494 
1495 static void
1496 spdk_nvmf_tcp_pdu_payload_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1497 				 struct spdk_nvmf_tcp_transport *ttransport)
1498 {
1499 	int rc = 0;
1500 	struct nvme_tcp_pdu *pdu;
1501 	uint32_t crc32c, error_offset = 0;
1502 	enum spdk_nvme_tcp_term_req_fes fes;
1503 
1504 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1505 	pdu = &tqpair->pdu_in_progress;
1506 
1507 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
1508 	/* check data digest if need */
1509 	if (pdu->ddgst_enable) {
1510 		crc32c = nvme_tcp_pdu_calc_data_digest(pdu);
1511 		rc = MATCH_DIGEST_WORD(pdu->data_digest, crc32c);
1512 		if (rc == 0) {
1513 			SPDK_ERRLOG("Data digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
1514 			fes = SPDK_NVME_TCP_TERM_REQ_FES_HDGST_ERROR;
1515 			spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1516 			return;
1517 
1518 		}
1519 	}
1520 
1521 	switch (pdu->hdr->common.pdu_type) {
1522 	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
1523 		spdk_nvmf_tcp_capsule_cmd_payload_handle(ttransport, tqpair, pdu);
1524 		break;
1525 	case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
1526 		spdk_nvmf_tcp_h2c_data_payload_handle(ttransport, tqpair, pdu);
1527 		break;
1528 
1529 	case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
1530 		spdk_nvmf_tcp_h2c_term_req_payload_handle(tqpair, pdu);
1531 		break;
1532 
1533 	default:
1534 		/* The code should not go to here */
1535 		SPDK_ERRLOG("The code should not go to here\n");
1536 		break;
1537 	}
1538 }
1539 
1540 static void
1541 spdk_nvmf_tcp_send_icresp_complete(void *cb_arg)
1542 {
1543 	struct spdk_nvmf_tcp_qpair *tqpair = cb_arg;
1544 
1545 	tqpair->state = NVME_TCP_QPAIR_STATE_RUNNING;
1546 }
1547 
1548 static void
1549 spdk_nvmf_tcp_icreq_handle(struct spdk_nvmf_tcp_transport *ttransport,
1550 			   struct spdk_nvmf_tcp_qpair *tqpair,
1551 			   struct nvme_tcp_pdu *pdu)
1552 {
1553 	struct spdk_nvme_tcp_ic_req *ic_req = &pdu->hdr->ic_req;
1554 	struct nvme_tcp_pdu *rsp_pdu;
1555 	struct spdk_nvme_tcp_ic_resp *ic_resp;
1556 	uint32_t error_offset = 0;
1557 	enum spdk_nvme_tcp_term_req_fes fes;
1558 
1559 	/* Only PFV 0 is defined currently */
1560 	if (ic_req->pfv != 0) {
1561 		SPDK_ERRLOG("Expected ICReq PFV %u, got %u\n", 0u, ic_req->pfv);
1562 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1563 		error_offset = offsetof(struct spdk_nvme_tcp_ic_req, pfv);
1564 		goto end;
1565 	}
1566 
1567 	/* MAXR2T is 0's based */
1568 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "maxr2t =%u\n", (ic_req->maxr2t + 1u));
1569 
1570 	tqpair->host_hdgst_enable = ic_req->dgst.bits.hdgst_enable ? true : false;
1571 	if (!tqpair->host_hdgst_enable) {
1572 		tqpair->pdu_recv_buf.size -= SPDK_NVME_TCP_DIGEST_LEN * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
1573 	}
1574 	tqpair->host_ddgst_enable = ic_req->dgst.bits.ddgst_enable ? true : false;
1575 	if (!tqpair->host_ddgst_enable) {
1576 		tqpair->pdu_recv_buf.size -= SPDK_NVME_TCP_DIGEST_LEN * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR;
1577 	}
1578 
1579 	tqpair->cpda = spdk_min(ic_req->hpda, SPDK_NVME_TCP_CPDA_MAX);
1580 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "cpda of tqpair=(%p) is : %u\n", tqpair, tqpair->cpda);
1581 
1582 	rsp_pdu = &tqpair->mgmt_pdu;
1583 
1584 	ic_resp = &rsp_pdu->hdr->ic_resp;
1585 	ic_resp->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_IC_RESP;
1586 	ic_resp->common.hlen = ic_resp->common.plen =  sizeof(*ic_resp);
1587 	ic_resp->pfv = 0;
1588 	ic_resp->cpda = tqpair->cpda;
1589 	ic_resp->maxh2cdata = ttransport->transport.opts.max_io_size;
1590 	ic_resp->dgst.bits.hdgst_enable = tqpair->host_hdgst_enable ? 1 : 0;
1591 	ic_resp->dgst.bits.ddgst_enable = tqpair->host_ddgst_enable ? 1 : 0;
1592 
1593 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "host_hdgst_enable: %u\n", tqpair->host_hdgst_enable);
1594 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "host_ddgst_enable: %u\n", tqpair->host_ddgst_enable);
1595 
1596 	tqpair->state = NVME_TCP_QPAIR_STATE_INITIALIZING;
1597 	spdk_nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, spdk_nvmf_tcp_send_icresp_complete, tqpair);
1598 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1599 	return;
1600 end:
1601 	spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1602 }
1603 
1604 static void
1605 spdk_nvmf_tcp_pdu_psh_handle(struct spdk_nvmf_tcp_qpair *tqpair,
1606 			     struct spdk_nvmf_tcp_transport *ttransport)
1607 {
1608 	struct nvme_tcp_pdu *pdu;
1609 	int rc;
1610 	uint32_t crc32c, error_offset = 0;
1611 	enum spdk_nvme_tcp_term_req_fes fes;
1612 
1613 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
1614 	pdu = &tqpair->pdu_in_progress;
1615 
1616 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "pdu type of tqpair(%p) is %d\n", tqpair,
1617 		      pdu->hdr->common.pdu_type);
1618 	/* check header digest if needed */
1619 	if (pdu->has_hdgst) {
1620 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Compare the header of pdu=%p on tqpair=%p\n", pdu, tqpair);
1621 		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
1622 		rc = MATCH_DIGEST_WORD((uint8_t *)pdu->hdr->raw + pdu->hdr->common.hlen, crc32c);
1623 		if (rc == 0) {
1624 			SPDK_ERRLOG("Header digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
1625 			fes = SPDK_NVME_TCP_TERM_REQ_FES_HDGST_ERROR;
1626 			spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1627 			return;
1628 
1629 		}
1630 	}
1631 
1632 	switch (pdu->hdr->common.pdu_type) {
1633 	case SPDK_NVME_TCP_PDU_TYPE_IC_REQ:
1634 		spdk_nvmf_tcp_icreq_handle(ttransport, tqpair, pdu);
1635 		break;
1636 	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
1637 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_REQ);
1638 		break;
1639 	case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
1640 		spdk_nvmf_tcp_h2c_data_hdr_handle(ttransport, tqpair, pdu);
1641 		break;
1642 
1643 	case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
1644 		spdk_nvmf_tcp_h2c_term_req_hdr_handle(tqpair, pdu);
1645 		break;
1646 
1647 	default:
1648 		SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", tqpair->pdu_in_progress.hdr->common.pdu_type);
1649 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1650 		error_offset = 1;
1651 		spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1652 		break;
1653 	}
1654 }
1655 
1656 static void
1657 spdk_nvmf_tcp_pdu_ch_handle(struct spdk_nvmf_tcp_qpair *tqpair)
1658 {
1659 	struct nvme_tcp_pdu *pdu;
1660 	uint32_t error_offset = 0;
1661 	enum spdk_nvme_tcp_term_req_fes fes;
1662 	uint8_t expected_hlen, pdo;
1663 	bool plen_error = false, pdo_error = false;
1664 
1665 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
1666 	pdu = &tqpair->pdu_in_progress;
1667 
1668 	if (pdu->hdr->common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_REQ) {
1669 		if (tqpair->state != NVME_TCP_QPAIR_STATE_INVALID) {
1670 			SPDK_ERRLOG("Already received ICreq PDU, and reject this pdu=%p\n", pdu);
1671 			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
1672 			goto err;
1673 		}
1674 		expected_hlen = sizeof(struct spdk_nvme_tcp_ic_req);
1675 		if (pdu->hdr->common.plen != expected_hlen) {
1676 			plen_error = true;
1677 		}
1678 	} else {
1679 		if (tqpair->state != NVME_TCP_QPAIR_STATE_RUNNING) {
1680 			SPDK_ERRLOG("The TCP/IP connection is not negotitated\n");
1681 			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
1682 			goto err;
1683 		}
1684 
1685 		switch (pdu->hdr->common.pdu_type) {
1686 		case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
1687 			expected_hlen = sizeof(struct spdk_nvme_tcp_cmd);
1688 			pdo = pdu->hdr->common.pdo;
1689 			if ((tqpair->cpda != 0) && (pdo != ((tqpair->cpda + 1) << 2))) {
1690 				pdo_error = true;
1691 				break;
1692 			}
1693 
1694 			if (pdu->hdr->common.plen < expected_hlen) {
1695 				plen_error = true;
1696 			}
1697 			break;
1698 		case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
1699 			expected_hlen = sizeof(struct spdk_nvme_tcp_h2c_data_hdr);
1700 			pdo = pdu->hdr->common.pdo;
1701 			if ((tqpair->cpda != 0) && (pdo != ((tqpair->cpda + 1) << 2))) {
1702 				pdo_error = true;
1703 				break;
1704 			}
1705 			if (pdu->hdr->common.plen < expected_hlen) {
1706 				plen_error = true;
1707 			}
1708 			break;
1709 
1710 		case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
1711 			expected_hlen = sizeof(struct spdk_nvme_tcp_term_req_hdr);
1712 			if ((pdu->hdr->common.plen <= expected_hlen) ||
1713 			    (pdu->hdr->common.plen > SPDK_NVME_TCP_TERM_REQ_PDU_MAX_SIZE)) {
1714 				plen_error = true;
1715 			}
1716 			break;
1717 
1718 		default:
1719 			SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", pdu->hdr->common.pdu_type);
1720 			fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1721 			error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdu_type);
1722 			goto err;
1723 		}
1724 	}
1725 
1726 	if (pdu->hdr->common.hlen != expected_hlen) {
1727 		SPDK_ERRLOG("PDU type=0x%02x, Expected ICReq header length %u, got %u on tqpair=%p\n",
1728 			    pdu->hdr->common.pdu_type,
1729 			    expected_hlen, pdu->hdr->common.hlen, tqpair);
1730 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1731 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, hlen);
1732 		goto err;
1733 	} else if (pdo_error) {
1734 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1735 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdo);
1736 	} else if (plen_error) {
1737 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1738 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, plen);
1739 		goto err;
1740 	} else {
1741 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
1742 		nvme_tcp_pdu_calc_psh_len(&tqpair->pdu_in_progress, tqpair->host_hdgst_enable);
1743 		return;
1744 	}
1745 err:
1746 	spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1747 }
1748 
1749 static int
1750 nvmf_tcp_pdu_payload_insert_dif(struct nvme_tcp_pdu *pdu, uint32_t read_offset,
1751 				int read_len)
1752 {
1753 	int rc;
1754 
1755 	rc = spdk_dif_generate_stream(pdu->data_iov, pdu->data_iovcnt,
1756 				      read_offset, read_len, pdu->dif_ctx);
1757 	if (rc != 0) {
1758 		SPDK_ERRLOG("DIF generate failed\n");
1759 	}
1760 
1761 	return rc;
1762 }
1763 
1764 static int
1765 nvme_tcp_recv_buf_read(struct spdk_sock *sock, struct nvme_tcp_pdu_recv_buf *pdu_recv_buf)
1766 {
1767 	int rc;
1768 
1769 	rc = nvme_tcp_read_data(sock, pdu_recv_buf->size - pdu_recv_buf->off,
1770 				(void *)pdu_recv_buf->buf + pdu_recv_buf->off);
1771 	if (rc < 0) {
1772 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "will disconnect sock=%p\n", sock);
1773 	} else if (rc > 0) {
1774 		pdu_recv_buf->remain_size = rc;
1775 		spdk_trace_record(TRACE_TCP_READ_FROM_SOCKET_DONE, 0, rc, 0, 0);
1776 	}
1777 
1778 	return rc;
1779 }
1780 
1781 static uint32_t
1782 nvme_tcp_read_data_from_pdu_recv_buf(struct nvme_tcp_pdu_recv_buf *pdu_recv_buf,
1783 				     uint32_t expected_size,
1784 				     char *dst)
1785 {
1786 	uint32_t size;
1787 
1788 	assert(pdu_recv_buf->remain_size > 0);
1789 	size = spdk_min(expected_size, pdu_recv_buf->remain_size);
1790 	if (dst) {
1791 		memcpy(dst, (void *)pdu_recv_buf->buf + pdu_recv_buf->off, size);
1792 	}
1793 	pdu_recv_buf->off += size;
1794 	pdu_recv_buf->remain_size -= size;
1795 
1796 
1797 	return size;
1798 }
1799 
1800 static int
1801 nvme_tcp_read_payload_data_from_pdu_recv_buf(struct nvme_tcp_pdu_recv_buf *pdu_recv_buf,
1802 		struct nvme_tcp_pdu *pdu)
1803 {
1804 	struct iovec iov[NVME_TCP_MAX_SGL_DESCRIPTORS + 1];
1805 	int iovcnt, i;
1806 	uint32_t size = 0;
1807 	void *dst;
1808 
1809 	assert(pdu_recv_buf->remain_size > 0);
1810 	iovcnt = nvme_tcp_build_payload_iovs(iov, NVME_TCP_MAX_SGL_DESCRIPTORS + 1, pdu,
1811 					     pdu->ddgst_enable, NULL);
1812 	assert(iovcnt >= 0);
1813 	for (i = 0; i < iovcnt; i++) {
1814 		if (!pdu_recv_buf->remain_size) {
1815 			break;
1816 		}
1817 
1818 		dst = NULL;
1819 		if (pdu->hdr->common.pdu_type != SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ) {
1820 			dst = iov[i].iov_base;
1821 		}
1822 		size += nvme_tcp_read_data_from_pdu_recv_buf(pdu_recv_buf, iov[i].iov_len, dst);
1823 	}
1824 
1825 	return size;
1826 }
1827 
1828 static int
1829 spdk_nvmf_tcp_sock_process(struct spdk_nvmf_tcp_qpair *tqpair)
1830 {
1831 	int rc = 0;
1832 	struct nvme_tcp_pdu *pdu;
1833 	enum nvme_tcp_pdu_recv_state prev_state;
1834 	uint32_t data_len;
1835 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport,
1836 			struct spdk_nvmf_tcp_transport, transport);
1837 
1838 	/* The loop here is to allow for several back-to-back state changes. */
1839 	do {
1840 		prev_state = tqpair->recv_state;
1841 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tqpair(%p) recv pdu entering state %d\n", tqpair, prev_state);
1842 
1843 		pdu = &tqpair->pdu_in_progress;
1844 		switch (tqpair->recv_state) {
1845 		/* Wait for the common header  */
1846 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY:
1847 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH:
1848 			if (spdk_unlikely(tqpair->state == NVME_TCP_QPAIR_STATE_INITIALIZING)) {
1849 				return rc;
1850 			}
1851 
1852 			if (!tqpair->pdu_recv_buf.remain_size) {
1853 				rc = nvme_tcp_recv_buf_read(tqpair->sock, &tqpair->pdu_recv_buf);
1854 				if (rc <= 0) {
1855 					return rc;
1856 				}
1857 			}
1858 			rc = nvme_tcp_read_data_from_pdu_recv_buf(&tqpair->pdu_recv_buf,
1859 					sizeof(struct spdk_nvme_tcp_common_pdu_hdr) - pdu->ch_valid_bytes,
1860 					NULL);
1861 			pdu->ch_valid_bytes += rc;
1862 			if (spdk_likely(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY)) {
1863 				spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
1864 			}
1865 
1866 			if (pdu->ch_valid_bytes < sizeof(struct spdk_nvme_tcp_common_pdu_hdr)) {
1867 				return NVME_TCP_PDU_IN_PROGRESS;
1868 			}
1869 
1870 			/* The command header of this PDU has now been read from the socket. */
1871 			spdk_nvmf_tcp_pdu_ch_handle(tqpair);
1872 			break;
1873 		/* Wait for the pdu specific header  */
1874 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH:
1875 			if (!tqpair->pdu_recv_buf.remain_size) {
1876 				rc = nvme_tcp_recv_buf_read(tqpair->sock, &tqpair->pdu_recv_buf);
1877 				if (rc <= 0) {
1878 					return rc;
1879 				}
1880 			}
1881 
1882 			rc = nvme_tcp_read_data_from_pdu_recv_buf(&tqpair->pdu_recv_buf,
1883 					pdu->psh_len - pdu->psh_valid_bytes,
1884 					NULL);
1885 			pdu->psh_valid_bytes += rc;
1886 			if (pdu->psh_valid_bytes < pdu->psh_len) {
1887 				return NVME_TCP_PDU_IN_PROGRESS;
1888 			}
1889 
1890 			/* All header(ch, psh, head digist) of this PDU has now been read from the socket. */
1891 			spdk_nvmf_tcp_pdu_psh_handle(tqpair, ttransport);
1892 			break;
1893 		/* Wait for the req slot */
1894 		case NVME_TCP_PDU_RECV_STATE_AWAIT_REQ:
1895 			spdk_nvmf_tcp_capsule_cmd_hdr_handle(ttransport, tqpair, pdu);
1896 			break;
1897 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:
1898 			/* check whether the data is valid, if not we just return */
1899 			if (!pdu->data_len) {
1900 				return NVME_TCP_PDU_IN_PROGRESS;
1901 			}
1902 
1903 			data_len = pdu->data_len;
1904 			/* data digest */
1905 			if (spdk_unlikely((pdu->hdr->common.pdu_type != SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ) &&
1906 					  tqpair->host_ddgst_enable)) {
1907 				data_len += SPDK_NVME_TCP_DIGEST_LEN;
1908 				pdu->ddgst_enable = true;
1909 			}
1910 
1911 			if (tqpair->pdu_recv_buf.remain_size) {
1912 				rc = nvme_tcp_read_payload_data_from_pdu_recv_buf(&tqpair->pdu_recv_buf, pdu);
1913 				pdu->readv_offset += rc;
1914 			}
1915 
1916 			if (pdu->readv_offset < data_len) {
1917 				rc = nvme_tcp_read_payload_data(tqpair->sock, pdu);
1918 				if (rc < 0) {
1919 					return NVME_TCP_PDU_IN_PROGRESS;
1920 				}
1921 				pdu->readv_offset += rc;
1922 			}
1923 
1924 			if (spdk_unlikely(pdu->dif_ctx != NULL)) {
1925 				rc = nvmf_tcp_pdu_payload_insert_dif(pdu, pdu->readv_offset - rc, rc);
1926 				if (rc != 0) {
1927 					return NVME_TCP_PDU_FATAL;
1928 				}
1929 			}
1930 
1931 			if (pdu->readv_offset < data_len) {
1932 				return NVME_TCP_PDU_IN_PROGRESS;
1933 			}
1934 
1935 			/* All of this PDU has now been read from the socket. */
1936 			spdk_nvmf_tcp_pdu_payload_handle(tqpair, ttransport);
1937 			break;
1938 		case NVME_TCP_PDU_RECV_STATE_ERROR:
1939 			if (!spdk_sock_is_connected(tqpair->sock)) {
1940 				return NVME_TCP_PDU_FATAL;
1941 			}
1942 			break;
1943 		default:
1944 			assert(0);
1945 			SPDK_ERRLOG("code should not come to here");
1946 			break;
1947 		}
1948 	} while (tqpair->recv_state != prev_state);
1949 
1950 	return rc;
1951 }
1952 
1953 static int
1954 spdk_nvmf_tcp_req_parse_sgl(struct spdk_nvmf_tcp_req *tcp_req,
1955 			    struct spdk_nvmf_transport *transport,
1956 			    struct spdk_nvmf_transport_poll_group *group)
1957 {
1958 	struct spdk_nvmf_request		*req = &tcp_req->req;
1959 	struct spdk_nvme_cmd			*cmd;
1960 	struct spdk_nvme_cpl			*rsp;
1961 	struct spdk_nvme_sgl_descriptor		*sgl;
1962 	uint32_t				length;
1963 
1964 	cmd = &req->cmd->nvme_cmd;
1965 	rsp = &req->rsp->nvme_cpl;
1966 	sgl = &cmd->dptr.sgl1;
1967 
1968 	length = sgl->unkeyed.length;
1969 
1970 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK &&
1971 	    sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_TRANSPORT) {
1972 		if (length > transport->opts.max_io_size) {
1973 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
1974 				    length, transport->opts.max_io_size);
1975 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
1976 			return -1;
1977 		}
1978 
1979 		/* fill request length and populate iovs */
1980 		req->length = length;
1981 
1982 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Data requested length= 0x%x\n", length);
1983 
1984 		if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
1985 			req->dif.orig_length = length;
1986 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
1987 			req->dif.elba_length = length;
1988 		}
1989 
1990 		if (spdk_nvmf_request_get_buffers(req, group, transport, length)) {
1991 			/* No available buffers. Queue this request up. */
1992 			SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "No available large data buffers. Queueing request %p\n",
1993 				      tcp_req);
1994 			return 0;
1995 		}
1996 
1997 		/* backward compatible */
1998 		req->data = req->iov[0].iov_base;
1999 
2000 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Request %p took %d buffer/s from central pool, and data=%p\n",
2001 			      tcp_req, req->iovcnt, req->data);
2002 
2003 		return 0;
2004 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
2005 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
2006 		uint64_t offset = sgl->address;
2007 		uint32_t max_len = transport->opts.in_capsule_data_size;
2008 
2009 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
2010 			      offset, length);
2011 
2012 		if (offset > max_len) {
2013 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
2014 				    offset, max_len);
2015 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
2016 			return -1;
2017 		}
2018 		max_len -= (uint32_t)offset;
2019 
2020 		if (length > max_len) {
2021 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
2022 				    length, max_len);
2023 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
2024 			return -1;
2025 		}
2026 
2027 		req->data = tcp_req->buf + offset;
2028 		req->data_from_pool = false;
2029 		req->length = length;
2030 
2031 		if (spdk_unlikely(req->dif.dif_insert_or_strip)) {
2032 			length = spdk_dif_get_length_with_md(length, &req->dif.dif_ctx);
2033 			req->dif.elba_length = length;
2034 		}
2035 
2036 		req->iov[0].iov_base = req->data;
2037 		req->iov[0].iov_len = length;
2038 		req->iovcnt = 1;
2039 
2040 		return 0;
2041 	}
2042 
2043 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
2044 		    sgl->generic.type, sgl->generic.subtype);
2045 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
2046 	return -1;
2047 }
2048 
2049 static inline enum spdk_nvme_media_error_status_code
2050 nvmf_tcp_dif_error_to_compl_status(uint8_t err_type) {
2051 	enum spdk_nvme_media_error_status_code result;
2052 
2053 	switch (err_type)
2054 	{
2055 	case SPDK_DIF_REFTAG_ERROR:
2056 		result = SPDK_NVME_SC_REFERENCE_TAG_CHECK_ERROR;
2057 		break;
2058 	case SPDK_DIF_APPTAG_ERROR:
2059 		result = SPDK_NVME_SC_APPLICATION_TAG_CHECK_ERROR;
2060 		break;
2061 	case SPDK_DIF_GUARD_ERROR:
2062 		result = SPDK_NVME_SC_GUARD_CHECK_ERROR;
2063 		break;
2064 	default:
2065 		SPDK_UNREACHABLE();
2066 		break;
2067 	}
2068 
2069 	return result;
2070 }
2071 
2072 static void
2073 spdk_nvmf_tcp_send_c2h_data(struct spdk_nvmf_tcp_qpair *tqpair,
2074 			    struct spdk_nvmf_tcp_req *tcp_req)
2075 {
2076 	struct nvme_tcp_pdu *rsp_pdu;
2077 	struct spdk_nvme_tcp_c2h_data_hdr *c2h_data;
2078 	uint32_t plen, pdo, alignment;
2079 	int rc;
2080 
2081 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
2082 
2083 	rsp_pdu = nvmf_tcp_req_pdu_init(tcp_req);
2084 	assert(rsp_pdu != NULL);
2085 
2086 	c2h_data = &rsp_pdu->hdr->c2h_data;
2087 	c2h_data->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_C2H_DATA;
2088 	plen = c2h_data->common.hlen = sizeof(*c2h_data);
2089 
2090 	if (tqpair->host_hdgst_enable) {
2091 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2092 		c2h_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
2093 	}
2094 
2095 	/* set the psh */
2096 	c2h_data->cccid = tcp_req->req.cmd->nvme_cmd.cid;
2097 	c2h_data->datal = tcp_req->req.length;
2098 	c2h_data->datao = 0;
2099 
2100 	/* set the padding */
2101 	rsp_pdu->padding_len = 0;
2102 	pdo = plen;
2103 	if (tqpair->cpda) {
2104 		alignment = (tqpair->cpda + 1) << 2;
2105 		if (alignment > plen) {
2106 			rsp_pdu->padding_len = alignment - plen;
2107 			pdo = plen = alignment;
2108 		}
2109 	}
2110 
2111 	c2h_data->common.pdo = pdo;
2112 	plen += c2h_data->datal;
2113 	if (tqpair->host_ddgst_enable) {
2114 		c2h_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_DDGSTF;
2115 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2116 	}
2117 
2118 	c2h_data->common.plen = plen;
2119 
2120 	if (spdk_unlikely(tcp_req->req.dif.dif_insert_or_strip)) {
2121 		rsp_pdu->dif_ctx = &tcp_req->req.dif.dif_ctx;
2122 	}
2123 
2124 	nvme_tcp_pdu_set_data_buf(rsp_pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
2125 				  c2h_data->datao, c2h_data->datal);
2126 
2127 	if (spdk_unlikely(tcp_req->req.dif.dif_insert_or_strip)) {
2128 		struct spdk_nvme_cpl *rsp = &tcp_req->req.rsp->nvme_cpl;
2129 		struct spdk_dif_error err_blk = {};
2130 
2131 		rc = spdk_dif_verify_stream(rsp_pdu->data_iov, rsp_pdu->data_iovcnt,
2132 					    0, rsp_pdu->data_len, rsp_pdu->dif_ctx, &err_blk);
2133 		if (rc != 0) {
2134 			SPDK_ERRLOG("DIF error detected. type=%d, offset=%" PRIu32 "\n",
2135 				    err_blk.err_type, err_blk.err_offset);
2136 			rsp->status.sct = SPDK_NVME_SCT_MEDIA_ERROR;
2137 			rsp->status.sc = nvmf_tcp_dif_error_to_compl_status(err_blk.err_type);
2138 			nvmf_tcp_req_pdu_fini(tcp_req);
2139 			spdk_nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
2140 			return;
2141 		}
2142 	}
2143 
2144 	c2h_data->common.flags |= SPDK_NVME_TCP_C2H_DATA_FLAGS_LAST_PDU;
2145 	if (tqpair->qpair.transport->opts.c2h_success) {
2146 		c2h_data->common.flags |= SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS;
2147 	}
2148 
2149 	spdk_nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, spdk_nvmf_tcp_pdu_c2h_data_complete, tcp_req);
2150 }
2151 
2152 static int
2153 request_transfer_out(struct spdk_nvmf_request *req)
2154 {
2155 	struct spdk_nvmf_tcp_req	*tcp_req;
2156 	struct spdk_nvmf_qpair		*qpair;
2157 	struct spdk_nvmf_tcp_qpair	*tqpair;
2158 	struct spdk_nvme_cpl		*rsp;
2159 
2160 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
2161 
2162 	qpair = req->qpair;
2163 	rsp = &req->rsp->nvme_cpl;
2164 	tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
2165 
2166 	/* Advance our sq_head pointer */
2167 	if (qpair->sq_head == qpair->sq_head_max) {
2168 		qpair->sq_head = 0;
2169 	} else {
2170 		qpair->sq_head++;
2171 	}
2172 	rsp->sqhd = qpair->sq_head;
2173 
2174 	tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
2175 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST);
2176 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS && req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2177 		spdk_nvmf_tcp_send_c2h_data(tqpair, tcp_req);
2178 	} else {
2179 		spdk_nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
2180 	}
2181 
2182 	return 0;
2183 }
2184 
2185 static void
2186 spdk_nvmf_tcp_set_incapsule_data(struct spdk_nvmf_tcp_qpair *tqpair,
2187 				 struct spdk_nvmf_tcp_req *tcp_req)
2188 {
2189 	struct nvme_tcp_pdu *pdu;
2190 	uint32_t plen = 0;
2191 
2192 	pdu = &tqpair->pdu_in_progress;
2193 	plen = pdu->hdr->common.hlen;
2194 
2195 	if (tqpair->host_hdgst_enable) {
2196 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2197 	}
2198 
2199 	if (pdu->hdr->common.plen != plen) {
2200 		tcp_req->has_incapsule_data = true;
2201 	}
2202 }
2203 
2204 static bool
2205 spdk_nvmf_tcp_req_process(struct spdk_nvmf_tcp_transport *ttransport,
2206 			  struct spdk_nvmf_tcp_req *tcp_req)
2207 {
2208 	struct spdk_nvmf_tcp_qpair		*tqpair;
2209 	int					rc;
2210 	enum spdk_nvmf_tcp_req_state		prev_state;
2211 	bool					progress = false;
2212 	struct spdk_nvmf_transport		*transport = &ttransport->transport;
2213 	struct spdk_nvmf_transport_poll_group	*group;
2214 
2215 	tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct spdk_nvmf_tcp_qpair, qpair);
2216 	group = &tqpair->group->group;
2217 	assert(tcp_req->state != TCP_REQUEST_STATE_FREE);
2218 
2219 	/* The loop here is to allow for several back-to-back state changes. */
2220 	do {
2221 		prev_state = tcp_req->state;
2222 
2223 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Request %p entering state %d on tqpair=%p\n", tcp_req, prev_state,
2224 			      tqpair);
2225 
2226 		switch (tcp_req->state) {
2227 		case TCP_REQUEST_STATE_FREE:
2228 			/* Some external code must kick a request into TCP_REQUEST_STATE_NEW
2229 			 * to escape this state. */
2230 			break;
2231 		case TCP_REQUEST_STATE_NEW:
2232 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_NEW, 0, 0, (uintptr_t)tcp_req, 0);
2233 
2234 			/* copy the cmd from the receive pdu */
2235 			tcp_req->cmd = tqpair->pdu_in_progress.hdr->capsule_cmd.ccsqe;
2236 
2237 			if (spdk_unlikely(spdk_nvmf_request_get_dif_ctx(&tcp_req->req, &tcp_req->req.dif.dif_ctx))) {
2238 				tcp_req->req.dif.dif_insert_or_strip = true;
2239 				tqpair->pdu_in_progress.dif_ctx = &tcp_req->req.dif.dif_ctx;
2240 			}
2241 
2242 			/* The next state transition depends on the data transfer needs of this request. */
2243 			tcp_req->req.xfer = spdk_nvmf_req_get_xfer(&tcp_req->req);
2244 
2245 			/* If no data to transfer, ready to execute. */
2246 			if (tcp_req->req.xfer == SPDK_NVME_DATA_NONE) {
2247 				/* Reset the tqpair receving pdu state */
2248 				spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2249 				spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
2250 				break;
2251 			}
2252 
2253 			spdk_nvmf_tcp_set_incapsule_data(tqpair, tcp_req);
2254 
2255 			if (!tcp_req->has_incapsule_data) {
2256 				spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2257 			}
2258 
2259 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEED_BUFFER);
2260 			STAILQ_INSERT_TAIL(&group->pending_buf_queue, &tcp_req->req, buf_link);
2261 			break;
2262 		case TCP_REQUEST_STATE_NEED_BUFFER:
2263 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_NEED_BUFFER, 0, 0, (uintptr_t)tcp_req, 0);
2264 
2265 			assert(tcp_req->req.xfer != SPDK_NVME_DATA_NONE);
2266 
2267 			if (!tcp_req->has_incapsule_data && (&tcp_req->req != STAILQ_FIRST(&group->pending_buf_queue))) {
2268 				SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP,
2269 					      "Not the first element to wait for the buf for tcp_req(%p) on tqpair=%p\n",
2270 					      tcp_req, tqpair);
2271 				/* This request needs to wait in line to obtain a buffer */
2272 				break;
2273 			}
2274 
2275 			/* Try to get a data buffer */
2276 			rc = spdk_nvmf_tcp_req_parse_sgl(tcp_req, transport, group);
2277 			if (rc < 0) {
2278 				STAILQ_REMOVE_HEAD(&group->pending_buf_queue, buf_link);
2279 				/* Reset the tqpair receving pdu state */
2280 				spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
2281 				spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2282 				break;
2283 			}
2284 
2285 			if (!tcp_req->req.data) {
2286 				SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "No buffer allocated for tcp_req(%p) on tqpair(%p\n)",
2287 					      tcp_req, tqpair);
2288 				/* No buffers available. */
2289 				break;
2290 			}
2291 
2292 			STAILQ_REMOVE(&group->pending_buf_queue, &tcp_req->req, spdk_nvmf_request, buf_link);
2293 
2294 			/* If data is transferring from host to controller, we need to do a transfer from the host. */
2295 			if (tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2296 				if (tcp_req->req.data_from_pool) {
2297 					SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Sending R2T for tcp_req(%p) on tqpair=%p\n", tcp_req, tqpair);
2298 					spdk_nvmf_tcp_send_r2t_pdu(tqpair, tcp_req);
2299 				} else {
2300 					struct nvme_tcp_pdu *pdu;
2301 
2302 					spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
2303 
2304 					pdu = &tqpair->pdu_in_progress;
2305 					SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Not need to send r2t for tcp_req(%p) on tqpair=%p\n", tcp_req,
2306 						      tqpair);
2307 					/* No need to send r2t, contained in the capsuled data */
2308 					nvme_tcp_pdu_set_data_buf(pdu, tcp_req->req.iov, tcp_req->req.iovcnt,
2309 								  0, tcp_req->req.length);
2310 					spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
2311 				}
2312 				break;
2313 			}
2314 
2315 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
2316 			break;
2317 		case TCP_REQUEST_STATE_AWAITING_R2T_ACK:
2318 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_AWAIT_R2T_ACK, 0, 0, (uintptr_t)tcp_req, 0);
2319 			/* The R2T completion or the h2c data incoming will kick it out of this state. */
2320 			break;
2321 		case TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2322 
2323 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2324 					  (uintptr_t)tcp_req, 0);
2325 			/* Some external code must kick a request into TCP_REQUEST_STATE_READY_TO_EXECUTE
2326 			 * to escape this state. */
2327 			break;
2328 		case TCP_REQUEST_STATE_READY_TO_EXECUTE:
2329 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE, 0, 0, (uintptr_t)tcp_req, 0);
2330 
2331 			if (spdk_unlikely(tcp_req->req.dif.dif_insert_or_strip)) {
2332 				assert(tcp_req->req.dif.elba_length >= tcp_req->req.length);
2333 				tcp_req->req.length = tcp_req->req.dif.elba_length;
2334 			}
2335 
2336 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTING);
2337 			spdk_nvmf_request_exec(&tcp_req->req);
2338 			break;
2339 		case TCP_REQUEST_STATE_EXECUTING:
2340 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_EXECUTING, 0, 0, (uintptr_t)tcp_req, 0);
2341 			/* Some external code must kick a request into TCP_REQUEST_STATE_EXECUTED
2342 			 * to escape this state. */
2343 			break;
2344 		case TCP_REQUEST_STATE_EXECUTED:
2345 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_EXECUTED, 0, 0, (uintptr_t)tcp_req, 0);
2346 
2347 			if (spdk_unlikely(tcp_req->req.dif.dif_insert_or_strip)) {
2348 				tcp_req->req.length = tcp_req->req.dif.orig_length;
2349 			}
2350 
2351 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2352 			break;
2353 		case TCP_REQUEST_STATE_READY_TO_COMPLETE:
2354 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE, 0, 0, (uintptr_t)tcp_req, 0);
2355 			rc = request_transfer_out(&tcp_req->req);
2356 			assert(rc == 0); /* No good way to handle this currently */
2357 			break;
2358 		case TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2359 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2360 					  (uintptr_t)tcp_req,
2361 					  0);
2362 			/* Some external code must kick a request into TCP_REQUEST_STATE_COMPLETED
2363 			 * to escape this state. */
2364 			break;
2365 		case TCP_REQUEST_STATE_COMPLETED:
2366 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_COMPLETED, 0, 0, (uintptr_t)tcp_req, 0);
2367 			if (tcp_req->req.data_from_pool) {
2368 				spdk_nvmf_request_free_buffers(&tcp_req->req, group, transport);
2369 			}
2370 			tcp_req->req.length = 0;
2371 			tcp_req->req.iovcnt = 0;
2372 			tcp_req->req.data = NULL;
2373 
2374 			nvmf_tcp_req_pdu_fini(tcp_req);
2375 
2376 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_FREE);
2377 			break;
2378 		case TCP_REQUEST_NUM_STATES:
2379 		default:
2380 			assert(0);
2381 			break;
2382 		}
2383 
2384 		if (tcp_req->state != prev_state) {
2385 			progress = true;
2386 		}
2387 	} while (tcp_req->state != prev_state);
2388 
2389 	return progress;
2390 }
2391 
2392 static void
2393 spdk_nvmf_tcp_sock_cb(void *arg, struct spdk_sock_group *group, struct spdk_sock *sock)
2394 {
2395 	struct spdk_nvmf_tcp_qpair *tqpair = arg;
2396 	int rc;
2397 
2398 	assert(tqpair != NULL);
2399 	rc = spdk_nvmf_tcp_sock_process(tqpair);
2400 
2401 	/* If there was a new socket error, disconnect */
2402 	if (rc < 0) {
2403 		spdk_nvmf_tcp_qpair_disconnect(tqpair);
2404 	}
2405 }
2406 
2407 static int
2408 spdk_nvmf_tcp_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
2409 			     struct spdk_nvmf_qpair *qpair)
2410 {
2411 	struct spdk_nvmf_tcp_poll_group	*tgroup;
2412 	struct spdk_nvmf_tcp_qpair	*tqpair;
2413 	int				rc;
2414 
2415 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2416 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
2417 
2418 	rc = spdk_sock_group_add_sock(tgroup->sock_group, tqpair->sock,
2419 				      spdk_nvmf_tcp_sock_cb, tqpair);
2420 	if (rc != 0) {
2421 		SPDK_ERRLOG("Could not add sock to sock_group: %s (%d)\n",
2422 			    spdk_strerror(errno), errno);
2423 		return -1;
2424 	}
2425 
2426 	rc =  spdk_nvmf_tcp_qpair_sock_init(tqpair);
2427 	if (rc != 0) {
2428 		SPDK_ERRLOG("Cannot set sock opt for tqpair=%p\n", tqpair);
2429 		return -1;
2430 	}
2431 
2432 	rc = spdk_nvmf_tcp_qpair_init(&tqpair->qpair);
2433 	if (rc < 0) {
2434 		SPDK_ERRLOG("Cannot init tqpair=%p\n", tqpair);
2435 		return -1;
2436 	}
2437 
2438 	rc = spdk_nvmf_tcp_qpair_init_mem_resource(tqpair);
2439 	if (rc < 0) {
2440 		SPDK_ERRLOG("Cannot init memory resource info for tqpair=%p\n", tqpair);
2441 		return -1;
2442 	}
2443 
2444 	tqpair->group = tgroup;
2445 	tqpair->state = NVME_TCP_QPAIR_STATE_INVALID;
2446 	TAILQ_INSERT_TAIL(&tgroup->qpairs, tqpair, link);
2447 
2448 	return 0;
2449 }
2450 
2451 static int
2452 spdk_nvmf_tcp_poll_group_remove(struct spdk_nvmf_transport_poll_group *group,
2453 				struct spdk_nvmf_qpair *qpair)
2454 {
2455 	struct spdk_nvmf_tcp_poll_group	*tgroup;
2456 	struct spdk_nvmf_tcp_qpair		*tqpair;
2457 	int				rc;
2458 
2459 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2460 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
2461 
2462 	assert(tqpair->group == tgroup);
2463 
2464 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "remove tqpair=%p from the tgroup=%p\n", tqpair, tgroup);
2465 	if (tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_REQ) {
2466 		TAILQ_REMOVE(&tgroup->await_req, tqpair, link);
2467 	} else {
2468 		TAILQ_REMOVE(&tgroup->qpairs, tqpair, link);
2469 	}
2470 
2471 	rc = spdk_sock_group_remove_sock(tgroup->sock_group, tqpair->sock);
2472 	if (rc != 0) {
2473 		SPDK_ERRLOG("Could not remove sock from sock_group: %s (%d)\n",
2474 			    spdk_strerror(errno), errno);
2475 	}
2476 
2477 	return rc;
2478 }
2479 
2480 static int
2481 spdk_nvmf_tcp_req_complete(struct spdk_nvmf_request *req)
2482 {
2483 	struct spdk_nvmf_tcp_transport *ttransport;
2484 	struct spdk_nvmf_tcp_req *tcp_req;
2485 
2486 	ttransport = SPDK_CONTAINEROF(req->qpair->transport, struct spdk_nvmf_tcp_transport, transport);
2487 	tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
2488 
2489 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTED);
2490 	spdk_nvmf_tcp_req_process(ttransport, tcp_req);
2491 
2492 	return 0;
2493 }
2494 
2495 static void
2496 spdk_nvmf_tcp_close_qpair(struct spdk_nvmf_qpair *qpair)
2497 {
2498 	struct spdk_nvmf_tcp_qpair *tqpair;
2499 
2500 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Qpair: %p\n", qpair);
2501 
2502 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
2503 	tqpair->state = NVME_TCP_QPAIR_STATE_EXITED;
2504 	spdk_nvmf_tcp_qpair_destroy(tqpair);
2505 }
2506 
2507 static int
2508 spdk_nvmf_tcp_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
2509 {
2510 	struct spdk_nvmf_tcp_poll_group *tgroup;
2511 	int rc;
2512 	struct spdk_nvmf_request *req, *req_tmp;
2513 	struct spdk_nvmf_tcp_req *tcp_req;
2514 	struct spdk_nvmf_tcp_qpair *tqpair, *tqpair_tmp;
2515 	struct spdk_nvmf_tcp_transport *ttransport = SPDK_CONTAINEROF(group->transport,
2516 			struct spdk_nvmf_tcp_transport, transport);
2517 
2518 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2519 
2520 	if (spdk_unlikely(TAILQ_EMPTY(&tgroup->qpairs) && TAILQ_EMPTY(&tgroup->await_req))) {
2521 		return 0;
2522 	}
2523 
2524 	STAILQ_FOREACH_SAFE(req, &group->pending_buf_queue, buf_link, req_tmp) {
2525 		tcp_req = SPDK_CONTAINEROF(req, struct spdk_nvmf_tcp_req, req);
2526 		if (spdk_nvmf_tcp_req_process(ttransport, tcp_req) == false) {
2527 			break;
2528 		}
2529 	}
2530 
2531 	rc = spdk_sock_group_poll(tgroup->sock_group);
2532 	if (rc < 0) {
2533 		SPDK_ERRLOG("Failed to poll sock_group=%p\n", tgroup->sock_group);
2534 	}
2535 
2536 	TAILQ_FOREACH_SAFE(tqpair, &tgroup->await_req, link, tqpair_tmp) {
2537 		spdk_nvmf_tcp_sock_process(tqpair);
2538 	}
2539 
2540 	return rc;
2541 }
2542 
2543 static int
2544 spdk_nvmf_tcp_qpair_get_trid(struct spdk_nvmf_qpair *qpair,
2545 			     struct spdk_nvme_transport_id *trid, bool peer)
2546 {
2547 	struct spdk_nvmf_tcp_qpair     *tqpair;
2548 	uint16_t			port;
2549 
2550 	tqpair = SPDK_CONTAINEROF(qpair, struct spdk_nvmf_tcp_qpair, qpair);
2551 	spdk_nvme_trid_populate_transport(trid, SPDK_NVME_TRANSPORT_TCP);
2552 
2553 	if (peer) {
2554 		snprintf(trid->traddr, sizeof(trid->traddr), "%s", tqpair->initiator_addr);
2555 		port = tqpair->initiator_port;
2556 	} else {
2557 		snprintf(trid->traddr, sizeof(trid->traddr), "%s", tqpair->target_addr);
2558 		port = tqpair->target_port;
2559 	}
2560 
2561 	if (spdk_sock_is_ipv4(tqpair->sock)) {
2562 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
2563 	} else if (spdk_sock_is_ipv6(tqpair->sock)) {
2564 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
2565 	} else {
2566 		return -1;
2567 	}
2568 
2569 	snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%d", port);
2570 	return 0;
2571 }
2572 
2573 static int
2574 spdk_nvmf_tcp_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
2575 				   struct spdk_nvme_transport_id *trid)
2576 {
2577 	return spdk_nvmf_tcp_qpair_get_trid(qpair, trid, 0);
2578 }
2579 
2580 static int
2581 spdk_nvmf_tcp_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
2582 				  struct spdk_nvme_transport_id *trid)
2583 {
2584 	return spdk_nvmf_tcp_qpair_get_trid(qpair, trid, 1);
2585 }
2586 
2587 static int
2588 spdk_nvmf_tcp_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
2589 				    struct spdk_nvme_transport_id *trid)
2590 {
2591 	return spdk_nvmf_tcp_qpair_get_trid(qpair, trid, 0);
2592 }
2593 
2594 #define SPDK_NVMF_TCP_DEFAULT_MAX_QUEUE_DEPTH 128
2595 #define SPDK_NVMF_TCP_DEFAULT_AQ_DEPTH 128
2596 #define SPDK_NVMF_TCP_DEFAULT_MAX_QPAIRS_PER_CTRLR 128
2597 #define SPDK_NVMF_TCP_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2598 #define SPDK_NVMF_TCP_DEFAULT_MAX_IO_SIZE 131072
2599 #define SPDK_NVMF_TCP_DEFAULT_IO_UNIT_SIZE 131072
2600 #define SPDK_NVMF_TCP_DEFAULT_NUM_SHARED_BUFFERS 511
2601 #define SPDK_NVMF_TCP_DEFAULT_BUFFER_CACHE_SIZE 32
2602 #define SPDK_NVMF_TCP_DEFAULT_SUCCESS_OPTIMIZATION true
2603 #define SPDK_NVMF_TCP_DEFAULT_DIF_INSERT_OR_STRIP false
2604 #define SPDK_NVMF_TCP_DEFAULT_SOCK_PRIORITY 0
2605 
2606 static void
2607 spdk_nvmf_tcp_opts_init(struct spdk_nvmf_transport_opts *opts)
2608 {
2609 	opts->max_queue_depth =		SPDK_NVMF_TCP_DEFAULT_MAX_QUEUE_DEPTH;
2610 	opts->max_qpairs_per_ctrlr =	SPDK_NVMF_TCP_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2611 	opts->in_capsule_data_size =	SPDK_NVMF_TCP_DEFAULT_IN_CAPSULE_DATA_SIZE;
2612 	opts->max_io_size =		SPDK_NVMF_TCP_DEFAULT_MAX_IO_SIZE;
2613 	opts->io_unit_size =		SPDK_NVMF_TCP_DEFAULT_IO_UNIT_SIZE;
2614 	opts->max_aq_depth =		SPDK_NVMF_TCP_DEFAULT_AQ_DEPTH;
2615 	opts->num_shared_buffers =	SPDK_NVMF_TCP_DEFAULT_NUM_SHARED_BUFFERS;
2616 	opts->buf_cache_size =		SPDK_NVMF_TCP_DEFAULT_BUFFER_CACHE_SIZE;
2617 	opts->c2h_success =		SPDK_NVMF_TCP_DEFAULT_SUCCESS_OPTIMIZATION;
2618 	opts->dif_insert_or_strip =	SPDK_NVMF_TCP_DEFAULT_DIF_INSERT_OR_STRIP;
2619 	opts->sock_priority =		SPDK_NVMF_TCP_DEFAULT_SOCK_PRIORITY;
2620 }
2621 
2622 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_tcp = {
2623 	.name = "TCP",
2624 	.type = SPDK_NVME_TRANSPORT_TCP,
2625 	.opts_init = spdk_nvmf_tcp_opts_init,
2626 	.create = spdk_nvmf_tcp_create,
2627 	.destroy = spdk_nvmf_tcp_destroy,
2628 
2629 	.listen = spdk_nvmf_tcp_listen,
2630 	.stop_listen = spdk_nvmf_tcp_stop_listen,
2631 	.accept = spdk_nvmf_tcp_accept,
2632 
2633 	.listener_discover = spdk_nvmf_tcp_discover,
2634 
2635 	.poll_group_create = spdk_nvmf_tcp_poll_group_create,
2636 	.get_optimal_poll_group = spdk_nvmf_tcp_get_optimal_poll_group,
2637 	.poll_group_destroy = spdk_nvmf_tcp_poll_group_destroy,
2638 	.poll_group_add = spdk_nvmf_tcp_poll_group_add,
2639 	.poll_group_remove = spdk_nvmf_tcp_poll_group_remove,
2640 	.poll_group_poll = spdk_nvmf_tcp_poll_group_poll,
2641 
2642 	.req_free = spdk_nvmf_tcp_req_free,
2643 	.req_complete = spdk_nvmf_tcp_req_complete,
2644 
2645 	.qpair_fini = spdk_nvmf_tcp_close_qpair,
2646 	.qpair_get_local_trid = spdk_nvmf_tcp_qpair_get_local_trid,
2647 	.qpair_get_peer_trid = spdk_nvmf_tcp_qpair_get_peer_trid,
2648 	.qpair_get_listen_trid = spdk_nvmf_tcp_qpair_get_listen_trid,
2649 };
2650 
2651 SPDK_NVMF_TRANSPORT_REGISTER(tcp, &spdk_nvmf_transport_tcp);
2652 SPDK_LOG_REGISTER_COMPONENT("nvmf_tcp", SPDK_LOG_NVMF_TCP)
2653