xref: /spdk/lib/nvmf/tcp.c (revision b7adc8fe835e134f5670147d275fc81edf009b87)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (c) Intel Corporation.
5  *   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.h"
40 #include "spdk/nvmf_spec.h"
41 #include "spdk/sock.h"
42 #include "spdk/string.h"
43 #include "spdk/trace.h"
44 #include "spdk/util.h"
45 
46 #include "nvmf_internal.h"
47 #include "transport.h"
48 
49 #include "spdk_internal/log.h"
50 #include "spdk_internal/nvme_tcp.h"
51 
52 /*
53  * AIO backend requires block size aligned data buffers,
54  * extra 4KiB aligned data buffer should work for most devices.
55  */
56 #define SHIFT_4KB			12u
57 #define NVMF_DATA_BUFFER_ALIGNMENT	(1u << SHIFT_4KB)
58 #define NVMF_DATA_BUFFER_MASK		(NVMF_DATA_BUFFER_ALIGNMENT - 1LL)
59 #define NVMF_TCP_MAX_ACCEPT_SOCK_ONE_TIME 16
60 
61 #define NVMF_TCP_PDU_MAX_H2C_DATA_SIZE	131072
62 #define NVMF_TCP_PDU_MAX_C2H_DATA_SIZE	131072
63 #define NVMF_TCP_QPAIR_MAX_C2H_PDU_NUM  64  /* Maximal c2h_data pdu number for ecah tqpair */
64 
65 /* This is used to support the Linux kernel NVMe-oF initiator */
66 #define LINUX_KERNEL_SUPPORT_NOT_SENDING_RESP_FOR_C2H 0
67 
68 /* spdk nvmf related structure */
69 enum spdk_nvmf_tcp_req_state {
70 
71 	/* The request is not currently in use */
72 	TCP_REQUEST_STATE_FREE = 0,
73 
74 	/* Initial state when request first received */
75 	TCP_REQUEST_STATE_NEW,
76 
77 	/* The request is queued until a data buffer is available. */
78 	TCP_REQUEST_STATE_NEED_BUFFER,
79 
80 	/* The request is pending on r2t slots */
81 	TCP_REQUEST_STATE_DATA_PENDING_FOR_R2T,
82 
83 	/* The request is currently transferring data from the host to the controller. */
84 	TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
85 
86 	/* The request is ready to execute at the block device */
87 	TCP_REQUEST_STATE_READY_TO_EXECUTE,
88 
89 	/* The request is currently executing at the block device */
90 	TCP_REQUEST_STATE_EXECUTING,
91 
92 	/* The request finished executing at the block device */
93 	TCP_REQUEST_STATE_EXECUTED,
94 
95 	/* The request is ready to send a completion */
96 	TCP_REQUEST_STATE_READY_TO_COMPLETE,
97 
98 	/* The request is currently transferring final pdus from the controller to the host. */
99 	TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
100 
101 	/* The request completed and can be marked free. */
102 	TCP_REQUEST_STATE_COMPLETED,
103 
104 	/* Terminator */
105 	TCP_REQUEST_NUM_STATES,
106 };
107 
108 static const char *spdk_nvme_tcp_term_req_fes_str[] = {
109 	"Invalid PDU Header Field",
110 	"PDU Sequence Error",
111 	"Header Digiest Error",
112 	"Data Transfer Out of Range",
113 	"R2T Limit Exceeded",
114 	"Unsupported parameter",
115 };
116 
117 #define OBJECT_NVMF_TCP_IO				0x80
118 
119 #define TRACE_GROUP_NVMF_TCP				0x5
120 #define TRACE_TCP_REQUEST_STATE_NEW					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x0)
121 #define TRACE_TCP_REQUEST_STATE_NEED_BUFFER				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x1)
122 #define TRACE_TCP_REQUEST_STATE_DATA_PENDING_FOR_R2T			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x2)
123 #define TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER		SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x3)
124 #define TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x4)
125 #define TRACE_TCP_REQUEST_STATE_EXECUTING				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x5)
126 #define TRACE_TCP_REQUEST_STATE_EXECUTED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x6)
127 #define TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE			SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x7)
128 #define TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST		SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x8)
129 #define TRACE_TCP_REQUEST_STATE_COMPLETED				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0x9)
130 #define TRACE_TCP_FLUSH_WRITEBUF_START					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0xA)
131 #define TRACE_TCP_FLUSH_WRITEBUF_DONE					SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0xB)
132 #define TRACE_TCP_FLUSH_WRITEBUF_PDU_DONE				SPDK_TPOINT_ID(TRACE_GROUP_NVMF_TCP, 0xC)
133 
134 SPDK_TRACE_REGISTER_FN(nvmf_tcp_trace, "nvmf_tcp", TRACE_GROUP_NVMF_TCP)
135 {
136 	spdk_trace_register_object(OBJECT_NVMF_TCP_IO, 'r');
137 	spdk_trace_register_description("TCP_REQ_NEW", "",
138 					TRACE_TCP_REQUEST_STATE_NEW,
139 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 1, 1, "");
140 	spdk_trace_register_description("TCP_REQ_NEED_BUFFER", "",
141 					TRACE_TCP_REQUEST_STATE_NEED_BUFFER,
142 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
143 	spdk_trace_register_description("TCP_REQ_TX_PENDING_R2T", "",
144 					TRACE_TCP_REQUEST_STATE_DATA_PENDING_FOR_R2T,
145 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
146 	spdk_trace_register_description("TCP_REQ_TX_H_TO_C", "",
147 					TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER,
148 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
149 	spdk_trace_register_description("TCP_REQ_RDY_TO_EXECUTE", "",
150 					TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE,
151 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
152 	spdk_trace_register_description("TCP_REQ_EXECUTING", "",
153 					TRACE_TCP_REQUEST_STATE_EXECUTING,
154 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
155 	spdk_trace_register_description("TCP_REQ_EXECUTED", "",
156 					TRACE_TCP_REQUEST_STATE_EXECUTED,
157 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
158 	spdk_trace_register_description("TCP_REQ_RDY_TO_COMPLETE", "",
159 					TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE,
160 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
161 	spdk_trace_register_description("TCP_REQ_COMPLETING_INCAPSULE", "",
162 					TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
163 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
164 	spdk_trace_register_description("TCP_REQ_COMPLETED", "",
165 					TRACE_TCP_REQUEST_STATE_COMPLETED,
166 					OWNER_NONE, OBJECT_NVMF_TCP_IO, 0, 1, "");
167 	spdk_trace_register_description("TCP_FLUSH_WRITEBUF_START", "",
168 					TRACE_TCP_FLUSH_WRITEBUF_START,
169 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
170 	spdk_trace_register_description("TCP_FLUSH_WRITEBUF_DONE", "",
171 					TRACE_TCP_FLUSH_WRITEBUF_DONE,
172 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
173 	spdk_trace_register_description("TCP_FLUSH_WRITEBUF_PDU_DONE", "",
174 					TRACE_TCP_FLUSH_WRITEBUF_PDU_DONE,
175 					OWNER_NONE, OBJECT_NONE, 0, 0, "");
176 }
177 
178 struct nvme_tcp_req  {
179 	struct spdk_nvmf_request		req;
180 	struct spdk_nvme_cpl			rsp;
181 	struct spdk_nvme_cmd			cmd;
182 
183 	/* In-capsule data buffer */
184 	uint8_t					*buf;
185 
186 	bool					data_from_pool;
187 	void					*buffers[SPDK_NVMF_MAX_SGL_ENTRIES];
188 
189 	/* transfer_tag */
190 	uint16_t				ttag;
191 
192 	/*
193 	 * next_expected_r2t_offset is used when we receive the h2c_data PDU.
194 	 */
195 	uint32_t				next_expected_r2t_offset;
196 	uint32_t				r2tl_remain;
197 
198 	/*
199 	 * c2h_data_offset is used when we send the c2h_data PDU.
200 	 */
201 	uint32_t				c2h_data_offset;
202 	uint32_t				c2h_data_pdu_num;
203 
204 	enum spdk_nvmf_tcp_req_state	state;
205 
206 	TAILQ_ENTRY(nvme_tcp_req)		link;
207 	TAILQ_ENTRY(nvme_tcp_req)		state_link;
208 };
209 
210 struct nvme_tcp_qpair {
211 	struct spdk_nvmf_qpair			qpair;
212 	struct spdk_nvmf_tcp_port		*port;
213 	struct spdk_sock			*sock;
214 	struct spdk_poller			*flush_poller;
215 
216 	enum nvme_tcp_pdu_recv_state		recv_state;
217 	enum nvme_tcp_qpair_state		state;
218 
219 	struct nvme_tcp_pdu			pdu_in_progress;
220 
221 	TAILQ_HEAD(, nvme_tcp_pdu)		send_queue;
222 	TAILQ_HEAD(, nvme_tcp_pdu)		free_queue;
223 
224 	struct nvme_tcp_pdu			*pdu;
225 	struct nvme_tcp_pdu			*pdu_pool;
226 	uint16_t				free_pdu_num;
227 
228 	/* Queues to track the requests in all states */
229 	TAILQ_HEAD(, nvme_tcp_req)		state_queue[TCP_REQUEST_NUM_STATES];
230 	/* Number of requests in each state */
231 	int32_t					state_cntr[TCP_REQUEST_NUM_STATES];
232 
233 	uint32_t				maxr2t;
234 	uint32_t				pending_r2t;
235 	TAILQ_HEAD(, nvme_tcp_req)		queued_r2t_tcp_req;
236 	TAILQ_HEAD(, nvme_tcp_req)		queued_c2h_data_tcp_req;
237 
238 	uint8_t					cpda;
239 
240 	/* Array of size "max_queue_depth * InCapsuleDataSize" containing
241 	 * buffers to be used for in capsule data.
242 	 */
243 	void					*buf;
244 	void					*bufs;
245 	struct nvme_tcp_req			*req;
246 	struct nvme_tcp_req			*reqs;
247 
248 	bool					host_hdgst_enable;
249 	bool					host_ddgst_enable;
250 
251 
252 	/* The maximum number of I/O outstanding on this connection at one time */
253 	uint16_t				max_queue_depth;
254 
255 
256 	/** Specifies the maximum number of PDU-Data bytes per H2C Data Transfer PDU */
257 	uint32_t				maxh2cdata;
258 
259 	/* Timer used to destroy qpair after detecting transport error issue if initiator does
260 	 *  not close the connection.
261 	 */
262 	uint64_t				last_pdu_time;
263 	int					timeout;
264 
265 	/* Mgmt channel */
266 	struct spdk_io_channel			*mgmt_channel;
267 	struct spdk_nvmf_tcp_mgmt_channel	*ch;
268 
269 	uint32_t				c2h_data_pdu_cnt;
270 
271 	/* IP address */
272 	char					initiator_addr[SPDK_NVMF_TRADDR_MAX_LEN];
273 	char					target_addr[SPDK_NVMF_TRADDR_MAX_LEN];
274 
275 	/* IP port */
276 	uint16_t				initiator_port;
277 	uint16_t				target_port;
278 
279 	/* qpair->group is freed early, this should be a temporal fix */
280 	struct spdk_nvmf_tcp_poll_group		*tgroup;
281 	TAILQ_ENTRY(nvme_tcp_qpair)		link;
282 };
283 
284 struct spdk_nvmf_tcp_poll_group {
285 	struct spdk_nvmf_transport_poll_group	group;
286 	struct spdk_sock_group			*sock_group;
287 	TAILQ_HEAD(, nvme_tcp_qpair)		qpairs;
288 };
289 
290 struct spdk_nvmf_tcp_port {
291 	struct spdk_nvme_transport_id		trid;
292 	struct spdk_sock			*listen_sock;
293 	uint32_t				ref;
294 	TAILQ_ENTRY(spdk_nvmf_tcp_port)		link;
295 };
296 
297 struct spdk_nvmf_tcp_transport {
298 	struct spdk_nvmf_transport		transport;
299 
300 	pthread_mutex_t				lock;
301 
302 	struct spdk_mempool			*data_buf_pool;
303 
304 	uint16_t				max_queue_depth;
305 	uint32_t				max_io_size;
306 	uint32_t				io_unit_size;
307 	uint32_t				in_capsule_data_size;
308 
309 	TAILQ_HEAD(, spdk_nvmf_tcp_port)	ports;
310 };
311 
312 struct spdk_nvmf_tcp_mgmt_channel {
313 	/* Requests that are waiting to obtain a data buffer */
314 	TAILQ_HEAD(, nvme_tcp_req)	pending_data_buf_queue;
315 };
316 
317 static bool spdk_nvmf_tcp_req_process(struct spdk_nvmf_tcp_transport *ttransport,
318 				      struct nvme_tcp_req *tcp_req);
319 static void spdk_nvmf_tcp_handle_pending_c2h_data_queue(struct nvme_tcp_qpair *tqpair);
320 
321 static void
322 spdk_nvmf_tcp_req_set_state(struct nvme_tcp_req *tcp_req,
323 			    enum spdk_nvmf_tcp_req_state state)
324 {
325 	struct spdk_nvmf_qpair *qpair;
326 	struct nvme_tcp_qpair *tqpair;
327 
328 	qpair = tcp_req->req.qpair;
329 	tqpair = SPDK_CONTAINEROF(qpair, struct nvme_tcp_qpair, qpair);
330 
331 	TAILQ_REMOVE(&tqpair->state_queue[tcp_req->state], tcp_req, state_link);
332 	tqpair->state_cntr[tcp_req->state]--;
333 	assert(tqpair->state_cntr[tcp_req->state] >= 0);
334 
335 	TAILQ_INSERT_TAIL(&tqpair->state_queue[state], tcp_req, state_link);
336 	tqpair->state_cntr[state]++;
337 
338 	tcp_req->state = state;
339 }
340 
341 static struct nvme_tcp_pdu *
342 spdk_nvmf_tcp_pdu_get(struct nvme_tcp_qpair *tqpair)
343 {
344 	struct nvme_tcp_pdu *pdu;
345 
346 	pdu = TAILQ_FIRST(&tqpair->free_queue);
347 	if (!pdu) {
348 		SPDK_ERRLOG("Unable to get PDU for tqpair=%p\n", tqpair);
349 		abort();
350 		return NULL;
351 	}
352 
353 	tqpair->free_pdu_num--;
354 	TAILQ_REMOVE(&tqpair->free_queue, pdu, tailq);
355 	memset(pdu, 0, sizeof(*pdu));
356 	pdu->ref = 1;
357 	pdu->tqpair = tqpair;
358 
359 	return pdu;
360 }
361 
362 static void
363 spdk_nvmf_tcp_pdu_put(struct nvme_tcp_pdu *pdu)
364 {
365 	struct nvme_tcp_qpair *tqpair;
366 	if (!pdu) {
367 		return;
368 	}
369 
370 	assert(pdu->ref > 0);
371 	assert(pdu->tqpair != NULL);
372 	tqpair = pdu->tqpair;
373 
374 	pdu->ref--;
375 	if (pdu->ref == 0) {
376 		tqpair->free_pdu_num++;
377 		TAILQ_INSERT_HEAD(&tqpair->free_queue, pdu, tailq);
378 	}
379 }
380 
381 static struct nvme_tcp_req *
382 spdk_nvmf_tcp_req_get(struct nvme_tcp_qpair *tqpair)
383 {
384 	struct nvme_tcp_req *tcp_req;
385 
386 	tcp_req = TAILQ_FIRST(&tqpair->state_queue[TCP_REQUEST_STATE_FREE]);
387 	if (!tcp_req) {
388 		SPDK_ERRLOG("Cannot allocate tcp_req on tqpair=%p\n", tqpair);
389 		return NULL;
390 	}
391 
392 	memset(&tcp_req->cmd, 0, sizeof(tcp_req->cmd));
393 	memset(&tcp_req->rsp, 0, sizeof(tcp_req->rsp));
394 	tcp_req->next_expected_r2t_offset = 0;
395 	tcp_req->r2tl_remain = 0;
396 	tcp_req->c2h_data_offset = 0;
397 
398 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEW);
399 	return tcp_req;
400 }
401 
402 static void
403 nvmf_tcp_request_free(struct nvme_tcp_req *tcp_req)
404 {
405 	struct spdk_nvmf_tcp_transport *ttransport;
406 
407 	if (!tcp_req) {
408 		return;
409 	}
410 
411 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tcp_req=%p will be freed\n", tcp_req);
412 	ttransport = SPDK_CONTAINEROF(tcp_req->req.qpair->transport,
413 				      struct spdk_nvmf_tcp_transport, transport);
414 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_COMPLETED);
415 	spdk_nvmf_tcp_req_process(ttransport, tcp_req);
416 }
417 
418 static int
419 spdk_nvmf_tcp_req_free(struct spdk_nvmf_request *req)
420 {
421 	struct nvme_tcp_req *tcp_req = SPDK_CONTAINEROF(req, struct nvme_tcp_req, req);
422 
423 	nvmf_tcp_request_free(tcp_req);
424 
425 	return 0;
426 }
427 
428 static int
429 spdk_nvmf_tcp_mgmt_channel_create(void *io_device, void *ctx_buf)
430 {
431 	struct spdk_nvmf_tcp_mgmt_channel *ch = ctx_buf;
432 
433 	TAILQ_INIT(&ch->pending_data_buf_queue);
434 	return 0;
435 }
436 
437 static void
438 spdk_nvmf_tcp_mgmt_channel_destroy(void *io_device, void *ctx_buf)
439 {
440 	struct spdk_nvmf_tcp_mgmt_channel *ch = ctx_buf;
441 
442 	if (!TAILQ_EMPTY(&ch->pending_data_buf_queue)) {
443 		SPDK_ERRLOG("Pending I/O list wasn't empty on channel destruction\n");
444 	}
445 }
446 
447 static void
448 spdk_nvmf_tcp_drain_state_queue(struct nvme_tcp_qpair *tqpair,
449 				enum spdk_nvmf_tcp_req_state state)
450 {
451 	struct nvme_tcp_req *tcp_req, *req_tmp;
452 
453 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->state_queue[state], state_link, req_tmp) {
454 		nvmf_tcp_request_free(tcp_req);
455 	}
456 }
457 
458 static void
459 spdk_nvmf_tcp_cleanup_all_states(struct nvme_tcp_qpair *tqpair)
460 {
461 	struct nvme_tcp_req *tcp_req, *req_tmp;
462 	struct nvme_tcp_pdu *pdu, *tmp_pdu;
463 
464 	/* For the requests in TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST,
465 	 * they can be refreed via the pdu in the send_queue
466 	  */
467 	TAILQ_FOREACH_SAFE(pdu, &tqpair->send_queue, tailq, tmp_pdu) {
468 		TAILQ_REMOVE(&tqpair->send_queue, pdu, tailq);
469 		assert(pdu->cb_fn != NULL);
470 		pdu->cb_fn(pdu->cb_arg);
471 		spdk_nvmf_tcp_pdu_put(pdu);
472 	}
473 
474 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_NEW);
475 
476 	/* Wipe the requests waiting for R2t  */
477 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->state_queue[TCP_REQUEST_STATE_DATA_PENDING_FOR_R2T], link,
478 			   req_tmp) {
479 		TAILQ_REMOVE(&tqpair->queued_r2t_tcp_req, tcp_req, link);
480 	}
481 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_DATA_PENDING_FOR_R2T);
482 
483 	/* Wipe the requests waiting for buffer from the global list */
484 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->state_queue[TCP_REQUEST_STATE_NEED_BUFFER], link, req_tmp) {
485 		TAILQ_REMOVE(&tqpair->ch->pending_data_buf_queue, tcp_req, link);
486 	}
487 
488 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_NEED_BUFFER);
489 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_EXECUTING);
490 
491 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->queued_c2h_data_tcp_req, link, req_tmp) {
492 		TAILQ_REMOVE(&tqpair->queued_c2h_data_tcp_req, tcp_req, link);
493 	}
494 
495 	spdk_nvmf_tcp_drain_state_queue(tqpair, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
496 }
497 
498 static void
499 spdk_nvmf_tcp_qpair_destroy(struct nvme_tcp_qpair *tqpair)
500 {
501 	struct spdk_nvmf_tcp_poll_group *tgroup;
502 	int                             rc;
503 
504 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
505 	tgroup = tqpair->tgroup;
506 
507 	if (tgroup) {
508 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "remove tqpair=%p from the tgroup=%p\n", tqpair, tgroup);
509 		TAILQ_REMOVE(&tgroup->qpairs, tqpair, link);
510 		rc = spdk_sock_group_remove_sock(tgroup->sock_group, tqpair->sock);
511 		if (rc != 0) {
512 			SPDK_ERRLOG("Could not remove sock from sock_group: %s (%d)\n",
513 				    spdk_strerror(errno), errno);
514 		}
515 	}
516 
517 	spdk_poller_unregister(&tqpair->flush_poller);
518 	spdk_sock_close(&tqpair->sock);
519 	spdk_nvmf_tcp_cleanup_all_states(tqpair);
520 	if (tqpair->mgmt_channel) {
521 		spdk_put_io_channel(tqpair->mgmt_channel);
522 	}
523 
524 	if (tqpair->free_pdu_num != (tqpair->max_queue_depth + NVMF_TCP_QPAIR_MAX_C2H_PDU_NUM)) {
525 		SPDK_ERRLOG("tqpair(%p) free pdu pool num is %u but should be %u\n", tqpair,
526 			    tqpair->free_pdu_num,
527 			    (tqpair->max_queue_depth + NVMF_TCP_QPAIR_MAX_C2H_PDU_NUM));
528 	}
529 
530 	if (tqpair->state_cntr[TCP_REQUEST_STATE_FREE] != tqpair->max_queue_depth) {
531 		SPDK_ERRLOG("tqpair(%p) free tcp request num is %u but should be %u\n", tqpair,
532 			    tqpair->state_cntr[TCP_REQUEST_STATE_FREE],
533 			    tqpair->max_queue_depth);
534 	}
535 
536 	if (tqpair->c2h_data_pdu_cnt != 0) {
537 		SPDK_ERRLOG("tqpair(%p) free c2h_data_pdu cnt is %u but should be 0\n", tqpair,
538 			    tqpair->c2h_data_pdu_cnt);
539 	}
540 
541 	free(tqpair->pdu);
542 	free(tqpair->pdu_pool);
543 	free(tqpair->req);
544 	free(tqpair->reqs);
545 	spdk_dma_free(tqpair->buf);
546 	spdk_dma_free(tqpair->bufs);
547 	free(tqpair);
548 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Leave\n");
549 }
550 
551 static struct spdk_nvmf_transport *
552 spdk_nvmf_tcp_create(struct spdk_nvmf_transport_opts *opts)
553 {
554 	struct spdk_nvmf_tcp_transport *ttransport;
555 	uint32_t			sge_count;
556 
557 	ttransport = calloc(1, sizeof(*ttransport));
558 	if (!ttransport) {
559 		return NULL;
560 	}
561 
562 	TAILQ_INIT(&ttransport->ports);
563 
564 	ttransport->transport.ops = &spdk_nvmf_transport_tcp;
565 
566 	SPDK_NOTICELOG("*** TCP Transport Init ***\n");
567 
568 	ttransport->max_queue_depth = opts->max_queue_depth;
569 	ttransport->max_io_size = opts->max_io_size;
570 	ttransport->in_capsule_data_size = opts->in_capsule_data_size;
571 	ttransport->io_unit_size = opts->io_unit_size;
572 
573 	/* I/O unit size cannot be larger than max I/O size */
574 	if (ttransport->io_unit_size > ttransport->max_io_size) {
575 		ttransport->io_unit_size = ttransport->max_io_size;
576 	}
577 
578 	sge_count = ttransport->max_io_size / ttransport->io_unit_size;
579 	if (sge_count > SPDK_NVMF_MAX_SGL_ENTRIES) {
580 		SPDK_ERRLOG("Unsupported IO Unit size specified, %d bytes\n", ttransport->io_unit_size);
581 		free(ttransport);
582 		return NULL;
583 	}
584 
585 	ttransport->data_buf_pool = spdk_mempool_create("spdk_nvmf_tcp_data",
586 				    ttransport->max_queue_depth * 4, /* The 4 is arbitrarily chosen. Needs to be configurable. */
587 				    ttransport->max_io_size + NVMF_DATA_BUFFER_ALIGNMENT,
588 				    SPDK_MEMPOOL_DEFAULT_CACHE_SIZE,
589 				    SPDK_ENV_SOCKET_ID_ANY);
590 
591 	if (!ttransport->data_buf_pool) {
592 		SPDK_ERRLOG("Unable to allocate buffer pool for poll group\n");
593 		free(ttransport);
594 		return NULL;
595 	}
596 
597 	pthread_mutex_init(&ttransport->lock, NULL);
598 
599 	spdk_io_device_register(ttransport, spdk_nvmf_tcp_mgmt_channel_create,
600 				spdk_nvmf_tcp_mgmt_channel_destroy,
601 				sizeof(struct spdk_nvmf_tcp_mgmt_channel), "tcp_transport");
602 
603 	return &ttransport->transport;
604 }
605 
606 static int
607 spdk_nvmf_tcp_destroy(struct spdk_nvmf_transport *transport)
608 {
609 	struct spdk_nvmf_tcp_transport	*ttransport;
610 
611 	assert(transport != NULL);
612 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
613 
614 	if (spdk_mempool_count(ttransport->data_buf_pool) != (ttransport->max_queue_depth * 4)) {
615 		SPDK_ERRLOG("transport buffer pool count is %zu but should be %u\n",
616 			    spdk_mempool_count(ttransport->data_buf_pool),
617 			    ttransport->max_queue_depth * 4);
618 	}
619 
620 	spdk_mempool_free(ttransport->data_buf_pool);
621 	spdk_io_device_unregister(ttransport, NULL);
622 	pthread_mutex_destroy(&ttransport->lock);
623 	free(ttransport);
624 	return 0;
625 }
626 
627 static int
628 _spdk_nvmf_tcp_trsvcid_to_int(const char *trsvcid)
629 {
630 	unsigned long long ull;
631 	char *end = NULL;
632 
633 	ull = strtoull(trsvcid, &end, 10);
634 	if (end == NULL || end == trsvcid || *end != '\0') {
635 		return -1;
636 	}
637 
638 	/* Valid TCP/IP port numbers are in [0, 65535] */
639 	if (ull > 65535) {
640 		return -1;
641 	}
642 
643 	return (int)ull;
644 }
645 
646 /**
647  * Canonicalize a listen address trid.
648  */
649 static int
650 _spdk_nvmf_tcp_canon_listen_trid(struct spdk_nvme_transport_id *canon_trid,
651 				 const struct spdk_nvme_transport_id *trid)
652 {
653 	int trsvcid_int;
654 
655 	trsvcid_int = _spdk_nvmf_tcp_trsvcid_to_int(trid->trsvcid);
656 	if (trsvcid_int < 0) {
657 		return -EINVAL;
658 	}
659 
660 	memset(canon_trid, 0, sizeof(*canon_trid));
661 	canon_trid->trtype = SPDK_NVME_TRANSPORT_TCP;
662 	canon_trid->adrfam = trid->adrfam;
663 	snprintf(canon_trid->traddr, sizeof(canon_trid->traddr), "%s", trid->traddr);
664 	snprintf(canon_trid->trsvcid, sizeof(canon_trid->trsvcid), "%d", trsvcid_int);
665 
666 	return 0;
667 }
668 
669 /**
670  * Find an existing listening port.
671  *
672  * Caller must hold ttransport->lock.
673  */
674 static struct spdk_nvmf_tcp_port *
675 _spdk_nvmf_tcp_find_port(struct spdk_nvmf_tcp_transport *ttransport,
676 			 const struct spdk_nvme_transport_id *trid)
677 {
678 	struct spdk_nvme_transport_id canon_trid;
679 	struct spdk_nvmf_tcp_port *port;
680 
681 	if (_spdk_nvmf_tcp_canon_listen_trid(&canon_trid, trid) != 0) {
682 		return NULL;
683 	}
684 
685 	TAILQ_FOREACH(port, &ttransport->ports, link) {
686 		if (spdk_nvme_transport_id_compare(&canon_trid, &port->trid) == 0) {
687 			return port;
688 		}
689 	}
690 
691 	return NULL;
692 }
693 
694 static int
695 spdk_nvmf_tcp_listen(struct spdk_nvmf_transport *transport,
696 		     const struct spdk_nvme_transport_id *trid)
697 {
698 	struct spdk_nvmf_tcp_transport *ttransport;
699 	struct spdk_nvmf_tcp_port *port;
700 	int trsvcid_int;
701 	uint8_t adrfam;
702 
703 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
704 
705 	trsvcid_int = _spdk_nvmf_tcp_trsvcid_to_int(trid->trsvcid);
706 	if (trsvcid_int < 0) {
707 		SPDK_ERRLOG("Invalid trsvcid '%s'\n", trid->trsvcid);
708 		return -EINVAL;
709 	}
710 
711 	pthread_mutex_lock(&ttransport->lock);
712 
713 	port = _spdk_nvmf_tcp_find_port(ttransport, trid);
714 	if (port) {
715 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Already listening on %s port %s\n",
716 			      trid->traddr, trid->trsvcid);
717 		port->ref++;
718 		pthread_mutex_unlock(&ttransport->lock);
719 		return 0;
720 	}
721 
722 	port = calloc(1, sizeof(*port));
723 	if (!port) {
724 		SPDK_ERRLOG("Port allocation failed\n");
725 		free(port);
726 		pthread_mutex_unlock(&ttransport->lock);
727 		return -ENOMEM;
728 	}
729 
730 	port->ref = 1;
731 
732 	if (_spdk_nvmf_tcp_canon_listen_trid(&port->trid, trid) != 0) {
733 		SPDK_ERRLOG("Invalid traddr %s / trsvcid %s\n",
734 			    trid->traddr, trid->trsvcid);
735 		free(port);
736 		pthread_mutex_unlock(&ttransport->lock);
737 		return -ENOMEM;
738 	}
739 
740 	port->listen_sock = spdk_sock_listen(trid->traddr, trsvcid_int);
741 	if (port->listen_sock == NULL) {
742 		SPDK_ERRLOG("spdk_sock_listen(%s, %d) failed: %s (%d)\n",
743 			    trid->traddr, trsvcid_int,
744 			    spdk_strerror(errno), errno);
745 		free(port);
746 		pthread_mutex_unlock(&ttransport->lock);
747 		return -errno;
748 	}
749 
750 	if (spdk_sock_is_ipv4(port->listen_sock)) {
751 		adrfam = SPDK_NVMF_ADRFAM_IPV4;
752 	} else if (spdk_sock_is_ipv6(port->listen_sock)) {
753 		adrfam = SPDK_NVMF_ADRFAM_IPV6;
754 	} else {
755 		SPDK_ERRLOG("Unhandled socket type\n");
756 		adrfam = 0;
757 	}
758 
759 	if (adrfam != trid->adrfam) {
760 		SPDK_ERRLOG("Socket address family mismatch\n");
761 		spdk_sock_close(&port->listen_sock);
762 		free(port);
763 		pthread_mutex_unlock(&ttransport->lock);
764 		return -EINVAL;
765 	}
766 
767 	SPDK_NOTICELOG("*** NVMe/TCP Target Listening on %s port %d ***\n",
768 		       trid->traddr, trsvcid_int);
769 
770 	TAILQ_INSERT_TAIL(&ttransport->ports, port, link);
771 	pthread_mutex_unlock(&ttransport->lock);
772 
773 	return 0;
774 }
775 
776 static int
777 spdk_nvmf_tcp_stop_listen(struct spdk_nvmf_transport *transport,
778 			  const struct spdk_nvme_transport_id *trid)
779 {
780 	struct spdk_nvmf_tcp_transport *ttransport;
781 	struct spdk_nvmf_tcp_port *port;
782 	int rc;
783 
784 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
785 
786 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Removing listen address %s port %s\n",
787 		      trid->traddr, trid->trsvcid);
788 
789 	pthread_mutex_lock(&ttransport->lock);
790 	port = _spdk_nvmf_tcp_find_port(ttransport, trid);
791 	if (port) {
792 		assert(port->ref > 0);
793 		port->ref--;
794 		if (port->ref == 0) {
795 			TAILQ_REMOVE(&ttransport->ports, port, link);
796 			spdk_sock_close(&port->listen_sock);
797 			free(port);
798 		}
799 		rc = 0;
800 	} else {
801 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Port not found\n");
802 		rc = -ENOENT;
803 	}
804 	pthread_mutex_unlock(&ttransport->lock);
805 
806 	return rc;
807 }
808 
809 static int
810 spdk_nvmf_tcp_qpair_flush_pdus_internal(struct nvme_tcp_qpair *tqpair)
811 {
812 	const int array_size = 32;
813 	struct iovec	iovec_array[array_size];
814 	struct iovec	*iov = iovec_array;
815 	int iovec_cnt = 0;
816 	int bytes = 0;
817 	int total_length = 0;
818 	uint32_t writev_offset;
819 	struct nvme_tcp_pdu *pdu;
820 	int pdu_length;
821 	TAILQ_HEAD(, nvme_tcp_pdu) completed_pdus_list;
822 
823 	pdu = TAILQ_FIRST(&tqpair->send_queue);
824 
825 	if (pdu == NULL) {
826 		return 0;
827 	}
828 
829 	/*
830 	 * Build up a list of iovecs for the first few PDUs in the
831 	 *  tqpair 's send_queue.
832 	 */
833 	while (pdu != NULL && ((array_size - iovec_cnt) >= 3)) {
834 		iovec_cnt += nvme_tcp_build_iovecs(&iovec_array[iovec_cnt],
835 						   pdu,
836 						   tqpair->host_hdgst_enable,
837 						   tqpair->host_ddgst_enable);
838 		total_length += pdu->hdr.common.plen;
839 		pdu = TAILQ_NEXT(pdu, tailq);
840 	}
841 
842 	/*
843 	 * Check if the first PDU was partially written out the last time
844 	 *  this function was called, and if so adjust the iovec array
845 	 *  accordingly.
846 	 */
847 	writev_offset = TAILQ_FIRST(&tqpair->send_queue)->writev_offset;
848 	total_length -= writev_offset;
849 	while ((writev_offset > 0) && (iovec_cnt > 0)) {
850 		if (writev_offset >= iov->iov_len) {
851 			writev_offset -= iov->iov_len;
852 			iov++;
853 			iovec_cnt--;
854 		} else {
855 			iov->iov_len -= writev_offset;
856 			iov->iov_base = (char *)iov->iov_base + writev_offset;
857 			writev_offset = 0;
858 		}
859 	}
860 
861 	spdk_trace_record(TRACE_TCP_FLUSH_WRITEBUF_START, 0, total_length, 0, iovec_cnt);
862 
863 	bytes = spdk_sock_writev(tqpair->sock, iov, iovec_cnt);
864 	if (bytes == -1) {
865 		if (errno == EWOULDBLOCK || errno == EAGAIN) {
866 			return 1;
867 		} else {
868 			SPDK_ERRLOG("spdk_sock_writev() failed, errno %d: %s\n",
869 				    errno, spdk_strerror(errno));
870 			return -1;
871 		}
872 	}
873 
874 	spdk_trace_record(TRACE_TCP_FLUSH_WRITEBUF_DONE, 0, bytes, 0, 0);
875 
876 	pdu = TAILQ_FIRST(&tqpair->send_queue);
877 
878 	/*
879 	 * Free any PDUs that were fully written.  If a PDU was only
880 	 *  partially written, update its writev_offset so that next
881 	 *  time only the unwritten portion will be sent to writev().
882 	 */
883 	TAILQ_INIT(&completed_pdus_list);
884 	while (bytes > 0) {
885 		pdu_length = pdu->hdr.common.plen - pdu->writev_offset;
886 		if (bytes >= pdu_length) {
887 			bytes -= pdu_length;
888 			TAILQ_REMOVE(&tqpair->send_queue, pdu, tailq);
889 			TAILQ_INSERT_TAIL(&completed_pdus_list, pdu, tailq);
890 			pdu = TAILQ_FIRST(&tqpair->send_queue);
891 
892 		} else {
893 			pdu->writev_offset += bytes;
894 			bytes = 0;
895 		}
896 	}
897 
898 	while (!TAILQ_EMPTY(&completed_pdus_list)) {
899 		pdu = TAILQ_FIRST(&completed_pdus_list);
900 		TAILQ_REMOVE(&completed_pdus_list, pdu, tailq);
901 		assert(pdu->cb_fn != NULL);
902 		pdu->cb_fn(pdu->cb_arg);
903 		spdk_nvmf_tcp_pdu_put(pdu);
904 	}
905 
906 	return TAILQ_EMPTY(&tqpair->send_queue) ? 0 : 1;
907 }
908 
909 static int
910 spdk_nvmf_tcp_qpair_flush_pdus(void *_tqpair)
911 {
912 	struct nvme_tcp_qpair *tqpair = _tqpair;
913 	int rc;
914 
915 	if (tqpair->state == NVME_TCP_QPAIR_STATE_RUNNING) {
916 		rc = spdk_nvmf_tcp_qpair_flush_pdus_internal(tqpair);
917 		if (rc == 0 && tqpair->flush_poller != NULL) {
918 			spdk_poller_unregister(&tqpair->flush_poller);
919 		} else if (rc == 1 && tqpair->flush_poller == NULL) {
920 			tqpair->flush_poller = spdk_poller_register(spdk_nvmf_tcp_qpair_flush_pdus,
921 					       tqpair, 50);
922 		}
923 	} else {
924 		/*
925 		 * If the tqpair state is not RUNNING, then
926 		 * keep trying to flush PDUs until our list is
927 		 * empty - to make sure all data is sent before
928 		 * closing the connection.
929 		 */
930 		do {
931 			rc = spdk_nvmf_tcp_qpair_flush_pdus_internal(tqpair);
932 		} while (rc == 1);
933 	}
934 
935 	if (rc < 0 && tqpair->state < NVME_TCP_QPAIR_STATE_EXITING) {
936 		/*
937 		 * If the poller has already started destruction of the tqpair,
938 		 *  i.e. the socket read failed, then the connection state may already
939 		 *  be EXITED.  We don't want to set it back to EXITING in that case.
940 		 */
941 		tqpair->state = NVME_TCP_QPAIR_STATE_EXITING;
942 	}
943 
944 	return -1;
945 }
946 
947 static void
948 spdk_nvmf_tcp_qpair_write_pdu(struct nvme_tcp_qpair *tqpair,
949 			      struct nvme_tcp_pdu *pdu,
950 			      nvme_tcp_qpair_xfer_complete_cb cb_fn,
951 			      void *cb_arg)
952 {
953 	int enable_digest;
954 	int hlen;
955 	uint32_t crc32c;
956 
957 	hlen = pdu->hdr.common.hlen;
958 	enable_digest = 1;
959 	if (pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_RESP ||
960 	    pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ) {
961 		/* this PDU should be sent without digest */
962 		enable_digest = 0;
963 	}
964 
965 	/* Header Digest */
966 	if (enable_digest && tqpair->host_hdgst_enable) {
967 		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
968 		MAKE_DIGEST_WORD((uint8_t *)pdu->hdr.raw + hlen, crc32c);
969 	}
970 
971 	/* Data Digest */
972 	if (pdu->data_len > 0 && enable_digest && tqpair->host_ddgst_enable) {
973 		crc32c = nvme_tcp_pdu_calc_data_digest(pdu);
974 		MAKE_DIGEST_WORD(pdu->data_digest, crc32c);
975 	}
976 
977 	pdu->cb_fn = cb_fn;
978 	pdu->cb_arg = cb_arg;
979 	TAILQ_INSERT_TAIL(&tqpair->send_queue, pdu, tailq);
980 	spdk_nvmf_tcp_qpair_flush_pdus(tqpair);
981 }
982 
983 static int
984 spdk_nvmf_tcp_qpair_init_mem_resource(struct nvme_tcp_qpair *tqpair, uint16_t size)
985 {
986 	int i;
987 	struct nvme_tcp_req *tcp_req;
988 	struct spdk_nvmf_tcp_transport *ttransport;
989 	ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport, struct spdk_nvmf_tcp_transport, transport);
990 
991 	if (!tqpair->qpair.sq_head_max) {
992 		tqpair->req = calloc(1, sizeof(*tqpair->req));
993 		if (!tqpair->req) {
994 			SPDK_ERRLOG("Unable to allocate req on tqpair=%p.\n", tqpair);
995 			return -1;
996 		}
997 
998 		if (ttransport->in_capsule_data_size) {
999 			tqpair->buf = spdk_dma_zmalloc(ttransport->in_capsule_data_size, 0x1000, NULL);
1000 			if (!tqpair->buf) {
1001 				SPDK_ERRLOG("Unable to allocate buf on tqpair=%p.\n", tqpair);
1002 				return -1;
1003 			}
1004 		}
1005 
1006 		tcp_req = tqpair->req;
1007 		tcp_req->ttag = 0;
1008 		tcp_req->req.qpair = &tqpair->qpair;
1009 
1010 		/* Set up memory to receive commands */
1011 		if (tqpair->buf) {
1012 			tcp_req->buf = tqpair->buf;
1013 		}
1014 
1015 		/* Set the cmdn and rsp */
1016 		tcp_req->req.rsp = (union nvmf_c2h_msg *)&tcp_req->rsp;
1017 		tcp_req->req.cmd = (union nvmf_h2c_msg *)&tcp_req->cmd;
1018 
1019 		/* Initialize request state to FREE */
1020 		tcp_req->state = TCP_REQUEST_STATE_FREE;
1021 		TAILQ_INSERT_TAIL(&tqpair->state_queue[tcp_req->state], tcp_req, state_link);
1022 
1023 		tqpair->pdu = calloc(NVMF_TCP_QPAIR_MAX_C2H_PDU_NUM + 1, sizeof(*tqpair->pdu));
1024 		if (!tqpair->pdu) {
1025 			SPDK_ERRLOG("Unable to allocate pdu on tqpair=%p.\n", tqpair);
1026 			return -1;
1027 		}
1028 
1029 		for (i = 0; i < 1 + NVMF_TCP_QPAIR_MAX_C2H_PDU_NUM; i++) {
1030 			TAILQ_INSERT_TAIL(&tqpair->free_queue, &tqpair->pdu[i], tailq);
1031 		}
1032 
1033 	} else {
1034 		tqpair->reqs = calloc(size, sizeof(*tqpair->reqs));
1035 		if (!tqpair->reqs) {
1036 			SPDK_ERRLOG("Unable to allocate reqs on tqpair=%p\n", tqpair);
1037 			return -1;
1038 		}
1039 
1040 		if (ttransport->in_capsule_data_size) {
1041 			tqpair->bufs = spdk_dma_zmalloc(size * ttransport->in_capsule_data_size,
1042 							0x1000, NULL);
1043 			if (!tqpair->bufs) {
1044 				SPDK_ERRLOG("Unable to allocate bufs on tqpair=%p.\n", tqpair);
1045 				return -1;
1046 			}
1047 		}
1048 
1049 		for (i = 0; i < size; i++) {
1050 			struct nvme_tcp_req *tcp_req = &tqpair->reqs[i];
1051 
1052 			tcp_req->ttag = i + 1;
1053 			tcp_req->req.qpair = &tqpair->qpair;
1054 
1055 			/* Set up memory to receive commands */
1056 			if (tqpair->bufs) {
1057 				tcp_req->buf = (void *)((uintptr_t)tqpair->bufs + (i * ttransport->in_capsule_data_size));
1058 			}
1059 
1060 			/* Set the cmdn and rsp */
1061 			tcp_req->req.rsp = (union nvmf_c2h_msg *)&tcp_req->rsp;
1062 			tcp_req->req.cmd = (union nvmf_h2c_msg *)&tcp_req->cmd;
1063 
1064 			/* Initialize request state to FREE */
1065 			tcp_req->state = TCP_REQUEST_STATE_FREE;
1066 			TAILQ_INSERT_TAIL(&tqpair->state_queue[tcp_req->state], tcp_req, state_link);
1067 		}
1068 
1069 		tqpair->pdu_pool = calloc(size, sizeof(*tqpair->pdu_pool));
1070 		if (!tqpair->pdu_pool) {
1071 			SPDK_ERRLOG("Unable to allocate pdu pool on tqpair =%p.\n", tqpair);
1072 			return -1;
1073 		}
1074 
1075 		for (i = 0; i < size; i++) {
1076 			TAILQ_INSERT_TAIL(&tqpair->free_queue, &tqpair->pdu_pool[i], tailq);
1077 		}
1078 	}
1079 
1080 	return 0;
1081 }
1082 
1083 static int
1084 spdk_nvmf_tcp_qpair_init(struct spdk_nvmf_qpair *qpair)
1085 {
1086 	struct spdk_nvmf_tcp_transport *ttransport;
1087 	struct nvme_tcp_qpair *tqpair;
1088 	int i;
1089 
1090 	ttransport = SPDK_CONTAINEROF(qpair->transport, struct spdk_nvmf_tcp_transport, transport);
1091 	tqpair = SPDK_CONTAINEROF(qpair, struct nvme_tcp_qpair, qpair);
1092 
1093 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "New TCP Connection: %p\n", qpair);
1094 
1095 	TAILQ_INIT(&tqpair->send_queue);
1096 	TAILQ_INIT(&tqpair->free_queue);
1097 	TAILQ_INIT(&tqpair->queued_r2t_tcp_req);
1098 	TAILQ_INIT(&tqpair->queued_c2h_data_tcp_req);
1099 
1100 	/* Initialise request state queues of the qpair */
1101 	for (i = TCP_REQUEST_STATE_FREE; i < TCP_REQUEST_NUM_STATES; i++) {
1102 		TAILQ_INIT(&tqpair->state_queue[i]);
1103 	}
1104 
1105 	tqpair->host_hdgst_enable = true;
1106 	tqpair->host_ddgst_enable = true;
1107 
1108 	tqpair->mgmt_channel = spdk_get_io_channel(ttransport);
1109 	if (!tqpair->mgmt_channel) {
1110 		return -1;
1111 	}
1112 	tqpair->ch = spdk_io_channel_get_ctx(tqpair->mgmt_channel);
1113 	assert(tqpair->ch != NULL);
1114 
1115 	return 0;
1116 }
1117 
1118 static int
1119 spdk_nvmf_tcp_qpair_sock_init(struct nvme_tcp_qpair *tqpair)
1120 {
1121 
1122 	int rc;
1123 	int buf_size;
1124 
1125 	/* set recv buffer size */
1126 	buf_size = 2 * 1024 * 1024;
1127 	rc = spdk_sock_set_recvbuf(tqpair->sock, buf_size);
1128 	if (rc != 0) {
1129 		SPDK_ERRLOG("spdk_sock_set_recvbuf failed\n");
1130 		return rc;
1131 	}
1132 
1133 	/* set send buffer size */
1134 	rc = spdk_sock_set_sendbuf(tqpair->sock, buf_size);
1135 	if (rc != 0) {
1136 		SPDK_ERRLOG("spdk_sock_set_sendbuf failed\n");
1137 		return rc;
1138 	}
1139 
1140 	/* set low water mark */
1141 	rc = spdk_sock_set_recvlowat(tqpair->sock, sizeof(struct spdk_nvme_tcp_c2h_data_hdr));
1142 	if (rc != 0) {
1143 		SPDK_ERRLOG("spdk_sock_set_recvlowat() failed\n");
1144 		return rc;
1145 	}
1146 
1147 	return 0;
1148 }
1149 
1150 static void
1151 _spdk_nvmf_tcp_handle_connect(struct spdk_nvmf_transport *transport,
1152 			      struct spdk_nvmf_tcp_port *port,
1153 			      struct spdk_sock *sock, new_qpair_fn cb_fn)
1154 {
1155 	struct nvme_tcp_qpair *tqpair;
1156 	int rc;
1157 
1158 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "New connection accepted on %s port %s\n",
1159 		      port->trid.traddr, port->trid.trsvcid);
1160 
1161 	tqpair = calloc(1, sizeof(struct nvme_tcp_qpair));
1162 	if (tqpair == NULL) {
1163 		SPDK_ERRLOG("Could not allocate new connection.\n");
1164 		spdk_sock_close(&sock);
1165 		return;
1166 	}
1167 
1168 	tqpair->sock = sock;
1169 	tqpair->max_queue_depth = 1;
1170 	tqpair->free_pdu_num = tqpair->max_queue_depth + NVMF_TCP_QPAIR_MAX_C2H_PDU_NUM;
1171 	tqpair->state_cntr[TCP_REQUEST_STATE_FREE] = tqpair->max_queue_depth;
1172 	tqpair->port = port;
1173 	tqpair->qpair.transport = transport;
1174 
1175 	rc = spdk_sock_getaddr(tqpair->sock, tqpair->target_addr,
1176 			       sizeof(tqpair->target_addr), &tqpair->target_port,
1177 			       tqpair->initiator_addr, sizeof(tqpair->initiator_addr),
1178 			       &tqpair->initiator_port);
1179 	if (rc < 0) {
1180 		SPDK_ERRLOG("spdk_sock_getaddr() failed of tqpair=%p\n", tqpair);
1181 		spdk_nvmf_tcp_qpair_destroy(tqpair);
1182 		return;
1183 	}
1184 
1185 	cb_fn(&tqpair->qpair);
1186 }
1187 
1188 static void
1189 spdk_nvmf_tcp_port_accept(struct spdk_nvmf_transport *transport, struct spdk_nvmf_tcp_port *port,
1190 			  new_qpair_fn cb_fn)
1191 {
1192 	struct spdk_sock *sock;
1193 	int i;
1194 
1195 	for (i = 0; i < NVMF_TCP_MAX_ACCEPT_SOCK_ONE_TIME; i++) {
1196 		sock = spdk_sock_accept(port->listen_sock);
1197 		if (sock) {
1198 			_spdk_nvmf_tcp_handle_connect(transport, port, sock, cb_fn);
1199 		}
1200 	}
1201 }
1202 
1203 static void
1204 spdk_nvmf_tcp_accept(struct spdk_nvmf_transport *transport, new_qpair_fn cb_fn)
1205 {
1206 	struct spdk_nvmf_tcp_transport *ttransport;
1207 	struct spdk_nvmf_tcp_port *port;
1208 
1209 	ttransport = SPDK_CONTAINEROF(transport, struct spdk_nvmf_tcp_transport, transport);
1210 
1211 	TAILQ_FOREACH(port, &ttransport->ports, link) {
1212 		spdk_nvmf_tcp_port_accept(transport, port, cb_fn);
1213 	}
1214 }
1215 
1216 static void
1217 spdk_nvmf_tcp_discover(struct spdk_nvmf_transport *transport,
1218 		       struct spdk_nvme_transport_id *trid,
1219 		       struct spdk_nvmf_discovery_log_page_entry *entry)
1220 {
1221 	entry->trtype = SPDK_NVMF_TRTYPE_TCP;
1222 	entry->adrfam = trid->adrfam;
1223 	entry->treq.secure_channel = SPDK_NVMF_TREQ_SECURE_CHANNEL_NOT_SPECIFIED;
1224 
1225 	spdk_strcpy_pad(entry->trsvcid, trid->trsvcid, sizeof(entry->trsvcid), ' ');
1226 	spdk_strcpy_pad(entry->traddr, trid->traddr, sizeof(entry->traddr), ' ');
1227 
1228 	entry->tsas.tcp.sectype = SPDK_NVME_TCP_SECURITY_NONE;
1229 }
1230 
1231 static struct spdk_nvmf_transport_poll_group *
1232 spdk_nvmf_tcp_poll_group_create(struct spdk_nvmf_transport *transport)
1233 {
1234 	struct spdk_nvmf_tcp_poll_group *tgroup;
1235 
1236 	tgroup = calloc(1, sizeof(*tgroup));
1237 	if (!tgroup) {
1238 		return NULL;
1239 	}
1240 
1241 	tgroup->sock_group = spdk_sock_group_create();
1242 	if (!tgroup->sock_group) {
1243 		goto cleanup;
1244 	}
1245 
1246 	TAILQ_INIT(&tgroup->qpairs);
1247 	return &tgroup->group;
1248 
1249 cleanup:
1250 	free(tgroup);
1251 	return NULL;
1252 }
1253 
1254 static void
1255 spdk_nvmf_tcp_poll_group_destroy(struct spdk_nvmf_transport_poll_group *group)
1256 {
1257 	struct spdk_nvmf_tcp_poll_group *tgroup;
1258 
1259 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
1260 	spdk_sock_group_close(&tgroup->sock_group);
1261 	free(tgroup);
1262 }
1263 
1264 static void
1265 spdk_nvmf_tcp_qpair_set_recv_state(struct nvme_tcp_qpair *tqpair,
1266 				   enum nvme_tcp_pdu_recv_state state)
1267 {
1268 	if (tqpair->recv_state == state) {
1269 		SPDK_ERRLOG("The recv state of tqpair=%p is same with the state(%d) to be set\n",
1270 			    tqpair, state);
1271 		return;
1272 	}
1273 
1274 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tqpair(%p) recv state=%d\n", tqpair, state);
1275 	tqpair->recv_state = state;
1276 	switch (state) {
1277 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH:
1278 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH:
1279 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:
1280 		break;
1281 	case NVME_TCP_PDU_RECV_STATE_ERROR:
1282 	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY:
1283 		memset(&tqpair->pdu_in_progress, 0, sizeof(tqpair->pdu_in_progress));
1284 		break;
1285 	default:
1286 		SPDK_ERRLOG("The state(%d) is invalid\n", state);
1287 		abort();
1288 		break;
1289 	}
1290 }
1291 
1292 static void
1293 spdk_nvmf_tcp_send_c2h_term_req_complete(void *cb_arg)
1294 {
1295 }
1296 
1297 static void
1298 spdk_nvmf_tcp_send_c2h_term_req(struct nvme_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu,
1299 				enum spdk_nvme_tcp_term_req_fes fes, uint32_t error_offset)
1300 {
1301 	struct nvme_tcp_pdu *rsp_pdu;
1302 	struct spdk_nvme_tcp_term_req_hdr *c2h_term_req;
1303 	uint32_t c2h_term_req_hdr_len = sizeof(*c2h_term_req);
1304 
1305 	rsp_pdu = spdk_nvmf_tcp_pdu_get(tqpair);
1306 	if (!rsp_pdu) {
1307 		tqpair->state = NVME_TCP_QPAIR_STATE_EXITING;
1308 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1309 		return;
1310 	}
1311 
1312 	c2h_term_req = &rsp_pdu->hdr.term_req;
1313 	c2h_term_req->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ;
1314 	c2h_term_req->common.hlen = c2h_term_req_hdr_len;
1315 	/* It should contain the header the received pdu */
1316 	c2h_term_req->common.plen = c2h_term_req->common.hlen + pdu->hdr.common.hlen;
1317 
1318 	if ((fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
1319 	    (fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
1320 		DSET32(&c2h_term_req->fei, error_offset);
1321 	}
1322 
1323 	/* copy the error code into the buffer */
1324 	rsp_pdu->data = (uint8_t *)rsp_pdu->hdr.raw + c2h_term_req_hdr_len;
1325 	if (pdu->hdr.common.plen <= SPDK_NVME_TCP_TERM_REQ_ERROR_DATA_MAX_SIZE) {
1326 		memcpy((uint8_t *)rsp_pdu->data, pdu->hdr.raw, pdu->hdr.common.plen);
1327 	} else {
1328 		memcpy((uint8_t *)rsp_pdu->data, pdu->hdr.raw, SPDK_NVME_TCP_TERM_REQ_ERROR_DATA_MAX_SIZE);
1329 	}
1330 
1331 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1332 	spdk_nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, spdk_nvmf_tcp_send_c2h_term_req_complete, tqpair);
1333 }
1334 
1335 static void
1336 spdk_nvmf_tcp_capsule_cmd_hdr_handle(struct spdk_nvmf_tcp_transport *ttransport,
1337 				     struct nvme_tcp_qpair *tqpair,
1338 				     struct nvme_tcp_pdu *pdu)
1339 {
1340 	struct nvme_tcp_req *tcp_req;
1341 
1342 	tcp_req = spdk_nvmf_tcp_req_get(tqpair);
1343 	if (!tcp_req) {
1344 		SPDK_ERRLOG("Cannot allocate tcp_req\n");
1345 		tqpair->state = NVME_TCP_QPAIR_STATE_EXITING;
1346 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1347 		return;
1348 	}
1349 
1350 	pdu->tcp_req = tcp_req;
1351 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEW);
1352 	spdk_nvmf_tcp_req_process(ttransport, tcp_req);
1353 	return;
1354 }
1355 
1356 static void
1357 spdk_nvmf_tcp_capsule_cmd_payload_handle(struct spdk_nvmf_tcp_transport *ttransport,
1358 		struct nvme_tcp_qpair *tqpair,
1359 		struct nvme_tcp_pdu *pdu)
1360 {
1361 	struct nvme_tcp_req *tcp_req;
1362 	struct spdk_nvme_tcp_cmd *capsule_cmd;
1363 	uint32_t error_offset = 0;
1364 	enum spdk_nvme_tcp_term_req_fes fes;
1365 
1366 	capsule_cmd = &pdu->hdr.capsule_cmd;
1367 	tcp_req = pdu->tcp_req;
1368 	assert(tcp_req != NULL);
1369 	if (capsule_cmd->common.pdo > SPDK_NVME_TCP_PDU_PDO_MAX_OFFSET) {
1370 		SPDK_ERRLOG("Expected ICReq capsule_cmd pdu offset <= %d, got %c\n",
1371 			    SPDK_NVME_TCP_PDU_PDO_MAX_OFFSET, capsule_cmd->common.pdo);
1372 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1373 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdo);
1374 		goto err;
1375 	}
1376 
1377 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1378 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1379 	spdk_nvmf_tcp_req_process(ttransport, tcp_req);
1380 
1381 	return;
1382 err:
1383 	spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1384 }
1385 
1386 static void
1387 spdk_nvmf_tcp_h2c_data_hdr_handle(struct spdk_nvmf_tcp_transport *ttransport,
1388 				  struct nvme_tcp_qpair *tqpair,
1389 				  struct nvme_tcp_pdu *pdu)
1390 {
1391 	struct nvme_tcp_req *tcp_req;
1392 	uint32_t error_offset = 0;
1393 	enum spdk_nvme_tcp_term_req_fes fes = 0;
1394 	struct spdk_nvme_tcp_h2c_data_hdr *h2c_data;
1395 	uint32_t iov_index;
1396 	bool ttag_offset_error = false;
1397 
1398 	h2c_data = &pdu->hdr.h2c_data;
1399 
1400 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tqpair=%p, r2t_info: datao=%u, datal=%u, cccid=%u, ttag=%u\n",
1401 		      tqpair, h2c_data->datao, h2c_data->datal, h2c_data->cccid, h2c_data->ttag);
1402 
1403 	/* According to the information in the pdu to find the req */
1404 	TAILQ_FOREACH(tcp_req, &tqpair->state_queue[TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER],
1405 		      state_link) {
1406 		if ((tcp_req->req.cmd->nvme_cmd.cid == h2c_data->cccid) && (tcp_req->ttag == h2c_data->ttag)) {
1407 			break;
1408 		}
1409 
1410 		if (!ttag_offset_error && (tcp_req->req.cmd->nvme_cmd.cid == h2c_data->cccid)) {
1411 			ttag_offset_error = true;
1412 		}
1413 	}
1414 
1415 	if (!tcp_req) {
1416 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tcp_req is not found for tqpair=%p\n", tqpair);
1417 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER;
1418 		if (!ttag_offset_error) {
1419 			error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, cccid);
1420 		} else {
1421 			error_offset = offsetof(struct spdk_nvme_tcp_h2c_data_hdr, ttag);
1422 		}
1423 		goto err;
1424 	}
1425 
1426 	if (tcp_req->next_expected_r2t_offset != h2c_data->datao) {
1427 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP,
1428 			      "tcp_req(%p), tqpair=%p,  expected_r2t_offset=%u, but data offset =%u\n",
1429 			      tcp_req, tqpair, tcp_req->next_expected_r2t_offset, h2c_data->datao);
1430 		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
1431 		goto err;
1432 	}
1433 
1434 	if (h2c_data->datal > tqpair->maxh2cdata) {
1435 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tcp_req(%p), tqpair=%p,  datao=%u execeeds maxh2cdata size=%u\n",
1436 			      tcp_req, tqpair, h2c_data->datao, tqpair->maxh2cdata);
1437 		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
1438 		goto err;
1439 	}
1440 
1441 	if ((h2c_data->datao + h2c_data->datal) > tcp_req->req.length) {
1442 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP,
1443 			      "tcp_req(%p), tqpair=%p,  (datao=%u + datal=%u) execeeds requested length=%u\n",
1444 			      tcp_req, tqpair, h2c_data->datao, h2c_data->datal, tcp_req->req.length);
1445 		fes = SPDK_NVME_TCP_TERM_REQ_FES_R2T_LIMIT_EXCEEDED;
1446 		goto err;
1447 	}
1448 
1449 	pdu->tcp_req = tcp_req;
1450 	pdu->data_len = h2c_data->datal;
1451 	iov_index = pdu->hdr.h2c_data.datao / ttransport->io_unit_size;
1452 	pdu->data = tcp_req->req.iov[iov_index].iov_base + (pdu->hdr.h2c_data.datao %
1453 			ttransport->io_unit_size);
1454 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1455 	return;
1456 
1457 err:
1458 	spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1459 }
1460 
1461 static void
1462 spdk_nvmf_tcp_pdu_cmd_complete(void *cb_arg)
1463 {
1464 	struct nvme_tcp_req *tcp_req = cb_arg;
1465 	nvmf_tcp_request_free(tcp_req);
1466 }
1467 
1468 static void
1469 spdk_nvmf_tcp_send_capsule_resp_pdu(struct nvme_tcp_req *tcp_req,
1470 				    struct nvme_tcp_qpair *tqpair)
1471 {
1472 	struct nvme_tcp_pdu *rsp_pdu;
1473 	struct spdk_nvme_tcp_rsp *capsule_resp;
1474 
1475 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter, tqpair=%p\n", tqpair);
1476 	rsp_pdu = spdk_nvmf_tcp_pdu_get(tqpair);
1477 	if (!rsp_pdu) {
1478 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1479 		tqpair->state = NVME_TCP_QPAIR_STATE_EXITING;
1480 		return;
1481 	}
1482 
1483 	capsule_resp = &rsp_pdu->hdr.capsule_resp;
1484 	capsule_resp->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_CAPSULE_RESP;
1485 	capsule_resp->common.plen = capsule_resp->common.hlen = sizeof(*capsule_resp);
1486 	capsule_resp->rccqe = tcp_req->req.rsp->nvme_cpl;
1487 	if (tqpair->host_hdgst_enable) {
1488 		capsule_resp->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
1489 		capsule_resp->common.plen += SPDK_NVME_TCP_DIGEST_LEN;
1490 	}
1491 
1492 	spdk_nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, spdk_nvmf_tcp_pdu_cmd_complete, tcp_req);
1493 }
1494 
1495 static void
1496 spdk_nvmf_tcp_pdu_c2h_data_complete(void *cb_arg)
1497 {
1498 	struct nvme_tcp_req *tcp_req = cb_arg;
1499 	struct nvme_tcp_qpair *tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair,
1500 					struct nvme_tcp_qpair, qpair);
1501 
1502 	assert(tqpair != NULL);
1503 	assert(tcp_req->c2h_data_pdu_num > 0);
1504 	tcp_req->c2h_data_pdu_num--;
1505 	if (!tcp_req->c2h_data_pdu_num) {
1506 #if LINUX_KERNEL_SUPPORT_NOT_SENDING_RESP_FOR_C2H
1507 		nvmf_tcp_request_free(tcp_req);
1508 #else
1509 		spdk_nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
1510 #endif
1511 	}
1512 
1513 	tqpair->c2h_data_pdu_cnt--;
1514 	spdk_nvmf_tcp_handle_pending_c2h_data_queue(tqpair);
1515 }
1516 
1517 static void
1518 spdk_nvmf_tcp_send_r2t_pdu(struct spdk_nvmf_tcp_transport *ttransport,
1519 			   struct nvme_tcp_qpair *tqpair,
1520 			   struct nvme_tcp_req *tcp_req)
1521 {
1522 	struct nvme_tcp_pdu *rsp_pdu;
1523 	struct spdk_nvme_tcp_r2t_hdr *r2t;
1524 
1525 	rsp_pdu = spdk_nvmf_tcp_pdu_get(tqpair);
1526 	if (!rsp_pdu) {
1527 		tqpair->state = NVME_TCP_QPAIR_STATE_EXITING;
1528 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1529 		return;
1530 	}
1531 
1532 	r2t = &rsp_pdu->hdr.r2t;
1533 	r2t->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_R2T;
1534 	r2t->common.plen = r2t->common.hlen = sizeof(*r2t);
1535 
1536 	if (tqpair->host_hdgst_enable) {
1537 		r2t->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
1538 		r2t->common.plen += SPDK_NVME_TCP_DIGEST_LEN;
1539 	}
1540 
1541 	r2t->cccid = tcp_req->req.cmd->nvme_cmd.cid;
1542 	r2t->ttag = tcp_req->ttag;
1543 	r2t->r2to = tcp_req->next_expected_r2t_offset;
1544 	r2t->r2tl = spdk_min(tcp_req->req.length - tcp_req->next_expected_r2t_offset, tqpair->maxh2cdata);
1545 	tcp_req->r2tl_remain = r2t->r2tl;
1546 
1547 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP,
1548 		      "tcp_req(%p) on tqpair(%p), r2t_info: cccid=%u, ttag=%u, r2to=%u, r2tl=%u\n",
1549 		      tcp_req, tqpair, r2t->cccid, r2t->ttag, r2t->r2to, r2t->r2tl);
1550 	spdk_nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, spdk_nvmf_tcp_pdu_cmd_complete, NULL);
1551 }
1552 
1553 static void
1554 spdk_nvmf_tcp_h2c_data_payload_handle(struct spdk_nvmf_tcp_transport *ttransport,
1555 				      struct nvme_tcp_qpair *tqpair,
1556 				      struct nvme_tcp_pdu *pdu)
1557 {
1558 	struct nvme_tcp_req *tcp_req;
1559 
1560 	tcp_req = pdu->tcp_req;
1561 	assert(tcp_req != NULL);
1562 
1563 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
1564 
1565 	tcp_req->next_expected_r2t_offset += pdu->data_len;
1566 	tcp_req->r2tl_remain -= pdu->data_len;
1567 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1568 
1569 	if (!tcp_req->r2tl_remain) {
1570 		if (tcp_req->next_expected_r2t_offset == tcp_req->req.length) {
1571 			assert(tqpair->pending_r2t > 0);
1572 			tqpair->pending_r2t--;
1573 			assert(tqpair->pending_r2t < tqpair->maxr2t);
1574 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
1575 			spdk_nvmf_tcp_req_process(ttransport, tcp_req);
1576 
1577 			/* fetch next */
1578 			tcp_req = TAILQ_FIRST(&tqpair->queued_r2t_tcp_req);
1579 			if (tcp_req) {
1580 				spdk_nvmf_tcp_req_process(ttransport, tcp_req);
1581 			}
1582 		} else {
1583 			SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Send r2t pdu for tcp_req=%p on tqpair=%p\n", tcp_req, tqpair);
1584 			spdk_nvmf_tcp_send_r2t_pdu(ttransport, tqpair, tcp_req);
1585 		}
1586 	}
1587 }
1588 
1589 static void
1590 spdk_nvmf_tcp_h2c_term_req_dump(struct spdk_nvme_tcp_term_req_hdr *h2c_term_req)
1591 {
1592 	SPDK_ERRLOG("Error info of pdu(%p): %s\n", h2c_term_req,
1593 		    spdk_nvme_tcp_term_req_fes_str[h2c_term_req->fes]);
1594 	if ((h2c_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
1595 	    (h2c_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
1596 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "The offset from the start of the PDU header is %u\n",
1597 			      DGET32(h2c_term_req->fei));
1598 	}
1599 }
1600 
1601 static void
1602 spdk_nvmf_tcp_h2c_term_req_hdr_handle(struct nvme_tcp_qpair *tqpair,
1603 				      struct nvme_tcp_pdu *pdu)
1604 {
1605 	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req = &pdu->hdr.term_req;
1606 	uint32_t error_offset = 0;
1607 	enum spdk_nvme_tcp_term_req_fes fes;
1608 
1609 
1610 	if (h2c_term_req->fes > SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER) {
1611 		SPDK_ERRLOG("Fatal Error Stauts(FES) is unknown for h2c_term_req pdu=%p\n", pdu);
1612 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1613 		error_offset = offsetof(struct spdk_nvme_tcp_term_req_hdr, fes);
1614 		goto end;
1615 	}
1616 
1617 	/* set the data buffer */
1618 	pdu->data = (uint8_t *)pdu->hdr.raw + h2c_term_req->common.hlen;
1619 	pdu->data_len = h2c_term_req->common.plen - h2c_term_req->common.hlen;
1620 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1621 	return;
1622 end:
1623 	spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1624 	return;
1625 }
1626 
1627 static void
1628 spdk_nvmf_tcp_h2c_term_req_payload_handle(struct nvme_tcp_qpair *tqpair,
1629 		struct nvme_tcp_pdu *pdu)
1630 {
1631 	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req = &pdu->hdr.term_req;
1632 
1633 	spdk_nvmf_tcp_h2c_term_req_dump(h2c_term_req);
1634 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1635 	return;
1636 }
1637 
1638 static void
1639 spdk_nvmf_tcp_pdu_payload_handle(struct nvme_tcp_qpair *tqpair)
1640 {
1641 	int rc = 0;
1642 	struct nvme_tcp_pdu *pdu;
1643 	uint32_t crc32c, error_offset = 0;
1644 	enum spdk_nvme_tcp_term_req_fes fes;
1645 	struct spdk_nvmf_tcp_transport *ttransport;
1646 
1647 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
1648 	pdu = &tqpair->pdu_in_progress;
1649 
1650 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
1651 	/* check data digest if need */
1652 	if (pdu->ddigest_valid_bytes) {
1653 		crc32c = nvme_tcp_pdu_calc_data_digest(pdu);
1654 		rc = MATCH_DIGEST_WORD(pdu->data_digest, crc32c);
1655 		if (rc == 0) {
1656 			SPDK_ERRLOG("Data digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
1657 			fes = SPDK_NVME_TCP_TERM_REQ_FES_HDGST_ERROR;
1658 			spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1659 			return;
1660 
1661 		}
1662 	}
1663 
1664 	ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport, struct spdk_nvmf_tcp_transport, transport);
1665 	switch (pdu->hdr.common.pdu_type) {
1666 	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
1667 		spdk_nvmf_tcp_capsule_cmd_payload_handle(ttransport, tqpair, pdu);
1668 		break;
1669 	case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
1670 		spdk_nvmf_tcp_h2c_data_payload_handle(ttransport, tqpair, pdu);
1671 		break;
1672 
1673 	case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
1674 		spdk_nvmf_tcp_h2c_term_req_payload_handle(tqpair, pdu);
1675 		break;
1676 
1677 	default:
1678 		/* The code should not go to here */
1679 		SPDK_ERRLOG("The code should not go to here\n");
1680 		break;
1681 	}
1682 }
1683 
1684 static void
1685 spdk_nvmf_tcp_send_icresp_complete(void *cb_arg)
1686 {
1687 	struct nvme_tcp_qpair *tqpair = cb_arg;
1688 
1689 	tqpair->state = NVME_TCP_QPAIR_STATE_RUNNING;
1690 }
1691 
1692 static void
1693 spdk_nvmf_tcp_icreq_handle(struct spdk_nvmf_tcp_transport *ttransport,
1694 			   struct nvme_tcp_qpair *tqpair,
1695 			   struct nvme_tcp_pdu *pdu)
1696 {
1697 	struct spdk_nvme_tcp_ic_req *ic_req = &pdu->hdr.ic_req;
1698 	struct nvme_tcp_pdu *rsp_pdu;
1699 	struct spdk_nvme_tcp_ic_resp *ic_resp;
1700 	uint32_t error_offset = 0;
1701 	enum spdk_nvme_tcp_term_req_fes fes;
1702 
1703 	/* Only PFV 0 is defined currently */
1704 	if (ic_req->pfv != 0) {
1705 		SPDK_ERRLOG("Expected ICReq PFV %u, got %u\n", 0u, ic_req->pfv);
1706 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1707 		error_offset = offsetof(struct spdk_nvme_tcp_ic_req, pfv);
1708 		goto end;
1709 	}
1710 
1711 	/* MAXR2T is 0's based */
1712 	tqpair->maxr2t = ic_req->maxr2t + 1ull;
1713 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "maxr2t =%u\n", tqpair->maxr2t);
1714 
1715 	tqpair->host_hdgst_enable = ic_req->dgst.bits.hdgst_enable ? true : false;
1716 	tqpair->host_ddgst_enable = ic_req->dgst.bits.ddgst_enable ? true : false;
1717 
1718 	tqpair->cpda = spdk_min(ic_req->hpda, SPDK_NVME_TCP_CPDA_MAX);
1719 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "cpda of tqpair=(%p) is : %u\n", tqpair, tqpair->cpda);
1720 
1721 	rsp_pdu = spdk_nvmf_tcp_pdu_get(tqpair);
1722 	if (!rsp_pdu) {
1723 		tqpair->state = NVME_TCP_QPAIR_STATE_EXITING;
1724 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1725 		return;
1726 	}
1727 
1728 	ic_resp = &rsp_pdu->hdr.ic_resp;
1729 	ic_resp->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_IC_RESP;
1730 	ic_resp->common.hlen = ic_resp->common.plen =  sizeof(*ic_resp);
1731 	ic_resp->pfv = 0;
1732 	ic_resp->cpda = tqpair->cpda;
1733 	tqpair->maxh2cdata = spdk_min(NVMF_TCP_PDU_MAX_H2C_DATA_SIZE, ttransport->io_unit_size);
1734 	ic_resp->maxh2cdata = tqpair->maxh2cdata;
1735 	ic_resp->dgst.bits.hdgst_enable = tqpair->host_hdgst_enable ? 1 : 0;
1736 	ic_resp->dgst.bits.ddgst_enable = tqpair->host_ddgst_enable ? 1 : 0;
1737 
1738 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "host_hdgst_enable: %u\n", tqpair->host_hdgst_enable);
1739 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "host_ddgst_enable: %u\n", tqpair->host_ddgst_enable);
1740 
1741 	spdk_nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, spdk_nvmf_tcp_send_icresp_complete, tqpair);
1742 	spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
1743 	return;
1744 end:
1745 	spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1746 	return;
1747 }
1748 
1749 static void
1750 spdk_nvmf_tcp_pdu_psh_handle(struct nvme_tcp_qpair *tqpair)
1751 {
1752 	struct nvme_tcp_pdu *pdu;
1753 	int rc;
1754 	uint32_t crc32c, error_offset = 0;
1755 	enum spdk_nvme_tcp_term_req_fes fes;
1756 	struct spdk_nvmf_tcp_transport *ttransport;
1757 
1758 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
1759 	pdu = &tqpair->pdu_in_progress;
1760 
1761 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "pdu type of tqpair(%p) is %d\n", tqpair,
1762 		      pdu->hdr.common.pdu_type);
1763 	/* check header digest if needed */
1764 	if (pdu->has_hdgst) {
1765 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Compare the header of pdu=%p on tqpair=%p\n", pdu, tqpair);
1766 		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
1767 		rc = MATCH_DIGEST_WORD((uint8_t *)pdu->hdr.raw + pdu->hdr.common.hlen, crc32c);
1768 		if (rc == 0) {
1769 			SPDK_ERRLOG("Header digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
1770 			fes = SPDK_NVME_TCP_TERM_REQ_FES_HDGST_ERROR;
1771 			spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1772 			return;
1773 
1774 		}
1775 	}
1776 
1777 	ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport, struct spdk_nvmf_tcp_transport, transport);
1778 	switch (pdu->hdr.common.pdu_type) {
1779 	case SPDK_NVME_TCP_PDU_TYPE_IC_REQ:
1780 		spdk_nvmf_tcp_icreq_handle(ttransport, tqpair, pdu);
1781 		break;
1782 	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
1783 		spdk_nvmf_tcp_capsule_cmd_hdr_handle(ttransport, tqpair, pdu);
1784 		break;
1785 	case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
1786 		spdk_nvmf_tcp_h2c_data_hdr_handle(ttransport, tqpair, pdu);
1787 		break;
1788 
1789 	case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
1790 		spdk_nvmf_tcp_h2c_term_req_hdr_handle(tqpair, pdu);
1791 		break;
1792 
1793 	default:
1794 		SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", tqpair->pdu_in_progress.hdr.common.pdu_type);
1795 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1796 		error_offset = 1;
1797 		spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1798 		break;
1799 	}
1800 }
1801 
1802 static void
1803 spdk_nvmf_tcp_pdu_ch_handle(struct nvme_tcp_qpair *tqpair)
1804 {
1805 	struct nvme_tcp_pdu *pdu;
1806 	uint32_t error_offset = 0;
1807 	enum spdk_nvme_tcp_term_req_fes fes;
1808 	uint8_t expected_hlen, pdo;
1809 	bool plen_error = false, pdo_error = false;
1810 
1811 	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
1812 	pdu = &tqpair->pdu_in_progress;
1813 
1814 	if (pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_REQ) {
1815 		if (tqpair->state != NVME_TCP_QPAIR_STATE_INVALID) {
1816 			SPDK_ERRLOG("Already received ICreq PDU, and reject this pdu=%p\n", pdu);
1817 			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
1818 			goto err;
1819 		}
1820 		expected_hlen = sizeof(struct spdk_nvme_tcp_ic_req);
1821 		if (pdu->hdr.common.plen != expected_hlen) {
1822 			plen_error = true;
1823 		}
1824 	} else {
1825 		if (tqpair->state != NVME_TCP_QPAIR_STATE_RUNNING) {
1826 			SPDK_ERRLOG("The TCP/IP connection is not negotitated\n");
1827 			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
1828 			goto err;
1829 		}
1830 
1831 		switch (pdu->hdr.common.pdu_type) {
1832 		case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD:
1833 			expected_hlen = sizeof(struct spdk_nvme_tcp_cmd);
1834 			pdo = pdu->hdr.common.pdo;
1835 			if ((tqpair->cpda != 0) && (pdo != ((tqpair->cpda + 1) << 2))) {
1836 				pdo_error = true;
1837 				break;
1838 			}
1839 
1840 			if (pdu->hdr.common.plen < expected_hlen) {
1841 				plen_error = true;
1842 			}
1843 			break;
1844 		case SPDK_NVME_TCP_PDU_TYPE_H2C_DATA:
1845 			expected_hlen = sizeof(struct spdk_nvme_tcp_h2c_data_hdr);
1846 			pdo = pdu->hdr.common.pdo;
1847 			if ((tqpair->cpda != 0) && (pdo != ((tqpair->cpda + 1) << 2))) {
1848 				pdo_error = true;
1849 				break;
1850 			}
1851 			if (pdu->hdr.common.plen < expected_hlen) {
1852 				plen_error = true;
1853 			}
1854 			break;
1855 
1856 		case SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ:
1857 			expected_hlen = sizeof(struct spdk_nvme_tcp_term_req_hdr);
1858 			if ((pdu->hdr.common.plen <= expected_hlen) ||
1859 			    (pdu->hdr.common.plen > SPDK_NVME_TCP_TERM_REQ_PDU_MAX_SIZE)) {
1860 				plen_error = true;
1861 			}
1862 			break;
1863 
1864 		default:
1865 			SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", pdu->hdr.common.pdu_type);
1866 			fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1867 			error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdu_type);
1868 			goto err;
1869 		}
1870 	}
1871 
1872 	if (pdu->hdr.common.hlen != expected_hlen) {
1873 		SPDK_ERRLOG("PDU type=0x%02x, Expected ICReq header length %u, got %u on tqpair=%p\n",
1874 			    pdu->hdr.common.pdu_type,
1875 			    expected_hlen, pdu->hdr.common.hlen, tqpair);
1876 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1877 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, hlen);
1878 		goto err;
1879 	} else if (pdo_error) {
1880 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1881 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdo);
1882 	} else if (plen_error) {
1883 		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
1884 		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, plen);
1885 		goto err;
1886 	} else {
1887 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
1888 		return;
1889 	}
1890 err:
1891 	spdk_nvmf_tcp_send_c2h_term_req(tqpair, pdu, fes, error_offset);
1892 }
1893 
1894 static int
1895 spdk_nvmf_tcp_sock_process(struct nvme_tcp_qpair *tqpair)
1896 {
1897 	int rc = 0;
1898 	struct nvme_tcp_pdu *pdu;
1899 	enum nvme_tcp_pdu_recv_state prev_state;
1900 	uint32_t data_len;
1901 	uint8_t psh_len, pdo, hlen;
1902 	int8_t  padding_len;
1903 
1904 	/* The loop here is to allow for several back-to-back state changes. */
1905 	do {
1906 		prev_state = tqpair->recv_state;
1907 
1908 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tqpair(%p) recv pdu entering state %d\n", tqpair, prev_state);
1909 
1910 		switch (tqpair->recv_state) {
1911 		/* If in a new state */
1912 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY:
1913 			spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
1914 			break;
1915 		/* Wait for the common header  */
1916 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH:
1917 			pdu = &tqpair->pdu_in_progress;
1918 			/* common header */
1919 			if (pdu->ch_valid_bytes < sizeof(struct spdk_nvme_tcp_common_pdu_hdr)) {
1920 				rc = nvme_tcp_read_data(tqpair->sock,
1921 							sizeof(struct spdk_nvme_tcp_common_pdu_hdr) - pdu->ch_valid_bytes,
1922 							(void *)&pdu->hdr.common + pdu->ch_valid_bytes);
1923 				if (rc < 0) {
1924 					SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "will disconnect tqpair=%p\n", tqpair);
1925 					spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1926 					break;
1927 				}
1928 				pdu->ch_valid_bytes += rc;
1929 				if (pdu->ch_valid_bytes < sizeof(struct spdk_nvme_tcp_common_pdu_hdr)) {
1930 					return NVME_TCP_PDU_IN_PROGRESS;
1931 				}
1932 			}
1933 
1934 			tqpair->last_pdu_time = spdk_get_ticks();
1935 			/* The command header of this PDU has now been read from the socket. */
1936 			spdk_nvmf_tcp_pdu_ch_handle(tqpair);
1937 			break;
1938 		/* Wait for the pdu specific header  */
1939 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH:
1940 			pdu = &tqpair->pdu_in_progress;
1941 			if (pdu->hd_is_read) {
1942 				break;
1943 			}
1944 
1945 			psh_len = hlen = pdu->hdr.common.hlen;
1946 			/* Only capsule_cmd and h2c_data has header digest */
1947 			if (((pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD) ||
1948 			     (pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_H2C_DATA)) &&
1949 			    tqpair->host_hdgst_enable) {
1950 				pdu->has_hdgst = true;
1951 				psh_len += SPDK_NVME_TCP_DIGEST_LEN;
1952 				if (pdu->hdr.common.plen > psh_len) {
1953 					pdo = pdu->hdr.common.pdo;
1954 					padding_len = pdo - psh_len;
1955 					SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "padding length is =%d for pdu=%p on tqpair=%p\n", padding_len,
1956 						      pdu, tqpair);
1957 					if (padding_len > 0) {
1958 						psh_len = pdo;
1959 					}
1960 				}
1961 			}
1962 
1963 			psh_len -= sizeof(struct spdk_nvme_tcp_common_pdu_hdr);
1964 			/* The following will read psh + hdgest (if possbile) + padding (if posssible) */
1965 			if (pdu->psh_valid_bytes < psh_len) {
1966 				rc = nvme_tcp_read_data(tqpair->sock,
1967 							psh_len - pdu->psh_valid_bytes,
1968 							(void *)&pdu->hdr.raw + sizeof(struct spdk_nvme_tcp_common_pdu_hdr) + pdu->psh_valid_bytes);
1969 				if (rc < 0) {
1970 					spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
1971 					break;
1972 				}
1973 
1974 				pdu->psh_valid_bytes += rc;
1975 				if (pdu->psh_valid_bytes < psh_len) {
1976 					return NVME_TCP_PDU_IN_PROGRESS;
1977 				}
1978 			}
1979 
1980 			pdu->hd_is_read = true;
1981 
1982 			/* All header(ch, psh, head digist) of this PDU has now been read from the socket. */
1983 			spdk_nvmf_tcp_pdu_psh_handle(tqpair);
1984 			break;
1985 		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:
1986 			pdu = &tqpair->pdu_in_progress;
1987 
1988 			/* check whether the data is valid, if not we just return */
1989 			if (!pdu->data) {
1990 				return NVME_TCP_PDU_IN_PROGRESS;
1991 			}
1992 
1993 			data_len = pdu->data_len;
1994 			/* data len */
1995 			if (pdu->data_valid_bytes < data_len) {
1996 				rc = nvme_tcp_read_data(tqpair->sock, data_len - pdu->data_valid_bytes,
1997 							(void *)pdu->data + pdu->data_valid_bytes);
1998 				if (rc < 0) {
1999 					spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
2000 					break;
2001 				}
2002 
2003 				pdu->data_valid_bytes += rc;
2004 				if (pdu->data_valid_bytes < data_len) {
2005 					return NVME_TCP_PDU_IN_PROGRESS;
2006 				}
2007 			}
2008 
2009 			/* data digest */
2010 			if ((pdu->hdr.common.pdu_type != SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ) &&
2011 			    tqpair->host_ddgst_enable && (pdu->ddigest_valid_bytes < SPDK_NVME_TCP_DIGEST_LEN)) {
2012 				rc = nvme_tcp_read_data(tqpair->sock,
2013 							SPDK_NVME_TCP_DIGEST_LEN - pdu->ddigest_valid_bytes,
2014 							pdu->data_digest + pdu->ddigest_valid_bytes);
2015 				if (rc < 0) {
2016 					spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
2017 					break;
2018 				}
2019 
2020 				pdu->ddigest_valid_bytes += rc;
2021 				if (pdu->ddigest_valid_bytes < SPDK_NVME_TCP_DIGEST_LEN) {
2022 					return NVME_TCP_PDU_IN_PROGRESS;
2023 				}
2024 			}
2025 
2026 			/* All of this PDU has now been read from the socket. */
2027 			spdk_nvmf_tcp_pdu_payload_handle(tqpair);
2028 			break;
2029 		case NVME_TCP_PDU_RECV_STATE_ERROR:
2030 			rc = NVME_TCP_PDU_FATAL;
2031 			break;
2032 		default:
2033 			assert(0);
2034 			SPDK_ERRLOG("code should not come to here");
2035 			break;
2036 		}
2037 	} while (tqpair->recv_state != prev_state);
2038 
2039 	return rc;
2040 }
2041 
2042 static enum spdk_nvme_data_transfer
2043 spdk_nvmf_tcp_req_get_xfer(struct nvme_tcp_req *tcp_req) {
2044 	enum spdk_nvme_data_transfer xfer;
2045 	struct spdk_nvme_cmd *cmd = &tcp_req->req.cmd->nvme_cmd;
2046 	struct spdk_nvme_sgl_descriptor *sgl = &cmd->dptr.sgl1;
2047 
2048 	/* Figure out data transfer direction */
2049 	if (cmd->opc == SPDK_NVME_OPC_FABRIC)
2050 	{
2051 		xfer = spdk_nvme_opc_get_data_transfer(tcp_req->req.cmd->nvmf_cmd.fctype);
2052 	} else
2053 	{
2054 		xfer = spdk_nvme_opc_get_data_transfer(cmd->opc);
2055 
2056 		/* Some admin commands are special cases */
2057 		if ((tcp_req->req.qpair->qid == 0) &&
2058 		    ((cmd->opc == SPDK_NVME_OPC_GET_FEATURES) ||
2059 		     (cmd->opc == SPDK_NVME_OPC_SET_FEATURES))) {
2060 			switch (cmd->cdw10 & 0xff) {
2061 			case SPDK_NVME_FEAT_LBA_RANGE_TYPE:
2062 			case SPDK_NVME_FEAT_AUTONOMOUS_POWER_STATE_TRANSITION:
2063 			case SPDK_NVME_FEAT_HOST_IDENTIFIER:
2064 				break;
2065 			default:
2066 				xfer = SPDK_NVME_DATA_NONE;
2067 			}
2068 		}
2069 	}
2070 
2071 	if (xfer == SPDK_NVME_DATA_NONE)
2072 	{
2073 		return xfer;
2074 	}
2075 
2076 	/* Even for commands that may transfer data, they could have specified 0 length.
2077 	 * We want those to show up with xfer SPDK_NVME_DATA_NONE.
2078 	 */
2079 	switch (sgl->generic.type)
2080 	{
2081 	case SPDK_NVME_SGL_TYPE_DATA_BLOCK:
2082 	case SPDK_NVME_SGL_TYPE_BIT_BUCKET:
2083 	case SPDK_NVME_SGL_TYPE_SEGMENT:
2084 	case SPDK_NVME_SGL_TYPE_LAST_SEGMENT:
2085 	case SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK:
2086 		if (sgl->unkeyed.length == 0) {
2087 			xfer = SPDK_NVME_DATA_NONE;
2088 		}
2089 		break;
2090 	case SPDK_NVME_SGL_TYPE_KEYED_DATA_BLOCK:
2091 		if (sgl->keyed.length == 0) {
2092 			xfer = SPDK_NVME_DATA_NONE;
2093 		}
2094 		break;
2095 	}
2096 
2097 	return xfer;
2098 }
2099 
2100 static int
2101 spdk_nvmf_tcp_req_fill_iovs(struct spdk_nvmf_tcp_transport *ttransport,
2102 			    struct nvme_tcp_req *tcp_req)
2103 {
2104 	void		*buf = NULL;
2105 	uint32_t	length = tcp_req->req.length;
2106 	uint32_t	i = 0;
2107 
2108 	tcp_req->req.iovcnt = 0;
2109 	while (length) {
2110 		buf = spdk_mempool_get(ttransport->data_buf_pool);
2111 		if (!buf) {
2112 			goto nomem;
2113 		}
2114 
2115 		tcp_req->req.iov[i].iov_base = (void *)((uintptr_t)(buf + NVMF_DATA_BUFFER_MASK) &
2116 							~NVMF_DATA_BUFFER_MASK);
2117 		tcp_req->req.iov[i].iov_len  = spdk_min(length, ttransport->io_unit_size);
2118 		tcp_req->req.iovcnt++;
2119 		tcp_req->buffers[i] = buf;
2120 		length -= tcp_req->req.iov[i].iov_len;
2121 		i++;
2122 	}
2123 
2124 	tcp_req->data_from_pool = true;
2125 
2126 	return 0;
2127 
2128 nomem:
2129 	while (i) {
2130 		i--;
2131 		spdk_mempool_put(ttransport->data_buf_pool, tcp_req->buffers[i]);
2132 		tcp_req->req.iov[i].iov_base = NULL;
2133 		tcp_req->req.iov[i].iov_len = 0;
2134 
2135 	}
2136 	tcp_req->req.iovcnt = 0;
2137 	return -ENOMEM;
2138 }
2139 
2140 static int
2141 spdk_nvmf_tcp_req_parse_sgl(struct spdk_nvmf_tcp_transport *ttransport,
2142 			    struct nvme_tcp_req *tcp_req)
2143 {
2144 	struct spdk_nvme_cmd			*cmd;
2145 	struct spdk_nvme_cpl			*rsp;
2146 	struct spdk_nvme_sgl_descriptor		*sgl;
2147 
2148 	cmd = &tcp_req->req.cmd->nvme_cmd;
2149 	rsp = &tcp_req->req.rsp->nvme_cpl;
2150 	sgl = &cmd->dptr.sgl1;
2151 
2152 	if (sgl->generic.type == SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK &&
2153 	    sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_TRANSPORT) {
2154 		if (sgl->unkeyed.length > ttransport->max_io_size) {
2155 			SPDK_ERRLOG("SGL length 0x%x exceeds max io size 0x%x\n",
2156 				    sgl->unkeyed.length, ttransport->max_io_size);
2157 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
2158 			return -1;
2159 		}
2160 
2161 		/* fill request length and populate iovs */
2162 		tcp_req->req.length = sgl->unkeyed.length;
2163 
2164 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Data requested length= 0x%x\n",
2165 			      sgl->unkeyed.length);
2166 
2167 		if (spdk_nvmf_tcp_req_fill_iovs(ttransport, tcp_req) < 0) {
2168 			/* No available buffers. Queue this request up. */
2169 			SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "No available large data buffers. Queueing request %p\n", tcp_req);
2170 			return 0;
2171 		}
2172 
2173 		/* backward compatible */
2174 		tcp_req->req.data = tcp_req->req.iov[0].iov_base;
2175 
2176 
2177 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Request %p took %d buffer/s from central pool, and data=%p\n",
2178 			      tcp_req,
2179 			      tcp_req->req.iovcnt, tcp_req->req.data);
2180 
2181 		return 0;
2182 	} else if (sgl->generic.type == SPDK_NVME_SGL_TYPE_DATA_BLOCK &&
2183 		   sgl->unkeyed.subtype == SPDK_NVME_SGL_SUBTYPE_OFFSET) {
2184 		uint64_t offset = sgl->address;
2185 		uint32_t max_len = ttransport->in_capsule_data_size;
2186 
2187 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "In-capsule data: offset 0x%" PRIx64 ", length 0x%x\n",
2188 			      offset, sgl->unkeyed.length);
2189 
2190 		if (offset > max_len) {
2191 			SPDK_ERRLOG("In-capsule offset 0x%" PRIx64 " exceeds capsule length 0x%x\n",
2192 				    offset, max_len);
2193 			rsp->status.sc = SPDK_NVME_SC_INVALID_SGL_OFFSET;
2194 			return -1;
2195 		}
2196 		max_len -= (uint32_t)offset;
2197 
2198 		if (sgl->unkeyed.length > max_len) {
2199 			SPDK_ERRLOG("In-capsule data length 0x%x exceeds capsule length 0x%x\n",
2200 				    sgl->unkeyed.length, max_len);
2201 			rsp->status.sc = SPDK_NVME_SC_DATA_SGL_LENGTH_INVALID;
2202 			return -1;
2203 		}
2204 
2205 		tcp_req->req.data = tcp_req->buf + offset;
2206 		tcp_req->data_from_pool = false;
2207 		tcp_req->req.length = sgl->unkeyed.length;
2208 
2209 		tcp_req->req.iov[0].iov_base = tcp_req->req.data;
2210 		tcp_req->req.iov[0].iov_len = tcp_req->req.length;
2211 		tcp_req->req.iovcnt = 1;
2212 
2213 		return 0;
2214 	}
2215 
2216 	SPDK_ERRLOG("Invalid NVMf I/O Command SGL:  Type 0x%x, Subtype 0x%x\n",
2217 		    sgl->generic.type, sgl->generic.subtype);
2218 	rsp->status.sc = SPDK_NVME_SC_SGL_DESCRIPTOR_TYPE_INVALID;
2219 	return -1;
2220 }
2221 
2222 static void
2223 spdk_nvmf_tcp_send_c2h_data(struct nvme_tcp_qpair *tqpair,
2224 			    struct nvme_tcp_req *tcp_req)
2225 {
2226 	struct nvme_tcp_pdu *rsp_pdu;
2227 	struct spdk_nvme_tcp_c2h_data_hdr *c2h_data;
2228 	uint32_t plen, pdo, alignment, offset, iov_index;
2229 
2230 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
2231 
2232 	/* always use the first iov_len, which is correct */
2233 	iov_index = tcp_req->c2h_data_offset / tcp_req->req.iov[0].iov_len;
2234 	offset = tcp_req->c2h_data_offset % tcp_req->req.iov[0].iov_len;
2235 
2236 	rsp_pdu = spdk_nvmf_tcp_pdu_get(tqpair);
2237 	assert(rsp_pdu != NULL);
2238 
2239 	c2h_data = &rsp_pdu->hdr.c2h_data;
2240 	c2h_data->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_C2H_DATA;
2241 	plen = c2h_data->common.hlen = sizeof(*c2h_data);
2242 
2243 	if (tqpair->host_hdgst_enable) {
2244 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2245 		c2h_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
2246 	}
2247 
2248 	/* set the psh */
2249 	c2h_data->cccid = tcp_req->req.cmd->nvme_cmd.cid;
2250 	c2h_data->datal = spdk_min(NVMF_TCP_PDU_MAX_C2H_DATA_SIZE,
2251 				   (tcp_req->req.iov[iov_index].iov_len - offset));
2252 	c2h_data->datao = tcp_req->c2h_data_offset;
2253 
2254 	/* set the padding */
2255 	rsp_pdu->padding_len = 0;
2256 	pdo = plen;
2257 	if (tqpair->cpda) {
2258 		alignment = (tqpair->cpda + 1) << 2;
2259 		if (alignment > plen) {
2260 			rsp_pdu->padding_len = alignment - plen;
2261 			pdo = plen = alignment;
2262 		}
2263 	}
2264 
2265 	c2h_data->common.pdo = pdo;
2266 	plen += c2h_data->datal;
2267 	if (tqpair->host_ddgst_enable) {
2268 		c2h_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_DDGSTF;
2269 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2270 	}
2271 
2272 	c2h_data->common.plen = plen;
2273 
2274 	rsp_pdu->data = tcp_req->req.iov[iov_index].iov_base + offset;
2275 	rsp_pdu->data_len = c2h_data->datal;
2276 
2277 	tcp_req->c2h_data_offset += c2h_data->datal;
2278 	if (iov_index == (tcp_req->req.iovcnt - 1) && (tcp_req->c2h_data_offset == tcp_req->req.length)) {
2279 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Last pdu for tcp_req=%p on tqpair=%p\n", tcp_req, tqpair);
2280 		c2h_data->common.flags |= SPDK_NVME_TCP_C2H_DATA_FLAGS_LAST_PDU;
2281 		/* The linux kernel does not support this yet */
2282 #if LINUX_KERNEL_SUPPORT_NOT_SENDING_RESP_FOR_C2H
2283 		c2h_data->common.flags |= SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS;
2284 #endif
2285 		TAILQ_REMOVE(&tqpair->queued_c2h_data_tcp_req, tcp_req, link);
2286 	}
2287 
2288 	tqpair->c2h_data_pdu_cnt += 1;
2289 	spdk_nvmf_tcp_qpair_write_pdu(tqpair, rsp_pdu, spdk_nvmf_tcp_pdu_c2h_data_complete, tcp_req);
2290 }
2291 
2292 static int
2293 spdk_nvmf_tcp_calc_c2h_data_pdu_num(struct nvme_tcp_req *tcp_req)
2294 {
2295 	uint32_t i, iov_cnt, pdu_num = 0;
2296 
2297 	iov_cnt = tcp_req->req.iovcnt;
2298 	for (i = 0; i < iov_cnt; i++) {
2299 		pdu_num += (tcp_req->req.iov[i].iov_len + NVMF_TCP_PDU_MAX_C2H_DATA_SIZE - 1) /
2300 			   NVMF_TCP_PDU_MAX_C2H_DATA_SIZE;
2301 	}
2302 
2303 	return pdu_num;
2304 }
2305 
2306 static void
2307 spdk_nvmf_tcp_handle_pending_c2h_data_queue(struct nvme_tcp_qpair *tqpair)
2308 {
2309 	struct nvme_tcp_req *tcp_req;
2310 
2311 	while (!TAILQ_EMPTY(&tqpair->queued_c2h_data_tcp_req) &&
2312 	       (tqpair->c2h_data_pdu_cnt < NVMF_TCP_QPAIR_MAX_C2H_PDU_NUM)) {
2313 		tcp_req = TAILQ_FIRST(&tqpair->queued_c2h_data_tcp_req);
2314 		spdk_nvmf_tcp_send_c2h_data(tqpair, tcp_req);
2315 	}
2316 }
2317 
2318 static void
2319 spdk_nvmf_tcp_queue_c2h_data(struct nvme_tcp_req *tcp_req,
2320 			     struct nvme_tcp_qpair *tqpair)
2321 {
2322 	tcp_req->c2h_data_pdu_num = spdk_nvmf_tcp_calc_c2h_data_pdu_num(tcp_req);
2323 
2324 	assert(tcp_req->c2h_data_pdu_num < NVMF_TCP_QPAIR_MAX_C2H_PDU_NUM);
2325 
2326 	TAILQ_INSERT_TAIL(&tqpair->queued_c2h_data_tcp_req, tcp_req, link);
2327 	spdk_nvmf_tcp_handle_pending_c2h_data_queue(tqpair);
2328 }
2329 
2330 static int
2331 request_transfer_out(struct spdk_nvmf_request *req)
2332 {
2333 	struct nvme_tcp_req	*tcp_req;
2334 	struct spdk_nvmf_qpair		*qpair;
2335 	struct nvme_tcp_qpair	*tqpair;
2336 	struct spdk_nvme_cpl		*rsp;
2337 
2338 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
2339 
2340 	qpair = req->qpair;
2341 	rsp = &req->rsp->nvme_cpl;
2342 	tcp_req = SPDK_CONTAINEROF(req, struct nvme_tcp_req, req);
2343 
2344 	/* Advance our sq_head pointer */
2345 	if (qpair->sq_head == qpair->sq_head_max) {
2346 		qpair->sq_head = 0;
2347 	} else {
2348 		qpair->sq_head++;
2349 	}
2350 	rsp->sqhd = qpair->sq_head;
2351 
2352 	tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct nvme_tcp_qpair, qpair);
2353 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST);
2354 	if (rsp->status.sc == SPDK_NVME_SC_SUCCESS &&
2355 	    req->xfer == SPDK_NVME_DATA_CONTROLLER_TO_HOST) {
2356 		spdk_nvmf_tcp_queue_c2h_data(tcp_req, tqpair);
2357 	} else {
2358 		spdk_nvmf_tcp_send_capsule_resp_pdu(tcp_req, tqpair);
2359 	}
2360 
2361 	return 0;
2362 }
2363 
2364 static void
2365 spdk_nvmf_tcp_pdu_set_buf_from_req(struct spdk_nvmf_tcp_transport *ttransport,
2366 				   struct nvme_tcp_qpair *tqpair,
2367 				   struct nvme_tcp_req *tcp_req)
2368 {
2369 	struct nvme_tcp_pdu *pdu;
2370 	uint32_t plen = 0;
2371 
2372 	pdu = &tqpair->pdu_in_progress;
2373 
2374 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "tqpair=%p\n", tqpair);
2375 	assert(pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD);
2376 
2377 	plen = pdu->hdr.common.hlen;
2378 	if (tqpair->host_hdgst_enable) {
2379 		plen += SPDK_NVME_TCP_DIGEST_LEN;
2380 	}
2381 
2382 	/* need to send r2t for data */
2383 	if (pdu->hdr.common.plen == plen) {
2384 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2385 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Will send r2t for tcp_req(%p) on tqpair=%p\n", tcp_req, tqpair);
2386 		tcp_req->next_expected_r2t_offset = 0;
2387 		TAILQ_INSERT_TAIL(&tqpair->queued_r2t_tcp_req, tcp_req, link);
2388 		spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_DATA_PENDING_FOR_R2T);
2389 
2390 	} else {
2391 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Not need to send r2t for tcp_req(%p) on tqpair=%p\n", tcp_req,
2392 			      tqpair);
2393 		/* No need to send r2t, contained in the capsuled data */
2394 		pdu->data = tcp_req->req.data;
2395 		pdu->data_len = tcp_req->req.length;
2396 		spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
2397 		spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
2398 	}
2399 }
2400 
2401 static bool
2402 spdk_nvmf_tcp_req_process(struct spdk_nvmf_tcp_transport *ttransport,
2403 			  struct nvme_tcp_req *tcp_req)
2404 {
2405 	struct nvme_tcp_qpair	*tqpair;
2406 	struct spdk_nvme_cpl		*rsp = &tcp_req->req.rsp->nvme_cpl;
2407 	int				rc;
2408 	enum spdk_nvmf_tcp_req_state prev_state;
2409 	bool				progress = false;
2410 
2411 	tqpair = SPDK_CONTAINEROF(tcp_req->req.qpair, struct nvme_tcp_qpair, qpair);
2412 	assert(tcp_req->state != TCP_REQUEST_STATE_FREE);
2413 
2414 	/* The loop here is to allow for several back-to-back state changes. */
2415 	do {
2416 		prev_state = tcp_req->state;
2417 
2418 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "Request %p entering state %d on tqpair=%p\n", tcp_req, prev_state,
2419 			      tqpair);
2420 
2421 		switch (tcp_req->state) {
2422 		case TCP_REQUEST_STATE_FREE:
2423 			/* Some external code must kick a request into TCP_REQUEST_STATE_NEW
2424 			 * to escape this state. */
2425 			break;
2426 		case TCP_REQUEST_STATE_NEW:
2427 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_NEW, 0, 0, (uintptr_t)tcp_req, 0);
2428 
2429 			/* copy the cmd from the receive pdu */
2430 			tcp_req->cmd = tqpair->pdu_in_progress.hdr.capsule_cmd.ccsqe;
2431 
2432 			/* The next state transition depends on the data transfer needs of this request. */
2433 			tcp_req->req.xfer = spdk_nvmf_tcp_req_get_xfer(tcp_req);
2434 
2435 			/* If no data to transfer, ready to execute. */
2436 			if (tcp_req->req.xfer == SPDK_NVME_DATA_NONE) {
2437 				/* Reset the tqpair receving pdu state */
2438 				spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2439 				spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
2440 				break;
2441 			}
2442 
2443 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_NEED_BUFFER);
2444 			TAILQ_INSERT_TAIL(&tqpair->ch->pending_data_buf_queue, tcp_req, link);
2445 			break;
2446 		case TCP_REQUEST_STATE_NEED_BUFFER:
2447 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_NEED_BUFFER, 0, 0, (uintptr_t)tcp_req, 0);
2448 
2449 			assert(tcp_req->req.xfer != SPDK_NVME_DATA_NONE);
2450 
2451 			if (tcp_req != TAILQ_FIRST(&tqpair->ch->pending_data_buf_queue)) {
2452 				SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP,
2453 					      "Not the first element to wait for the buf for tcp_req(%p) on tqpair=%p\n",
2454 					      tcp_req, tqpair);
2455 				/* This request needs to wait in line to obtain a buffer */
2456 				break;
2457 			}
2458 
2459 			/* Try to get a data buffer */
2460 			rc = spdk_nvmf_tcp_req_parse_sgl(ttransport, tcp_req);
2461 			if (rc < 0) {
2462 				TAILQ_REMOVE(&tqpair->ch->pending_data_buf_queue, tcp_req, link);
2463 				rsp->status.sc = SPDK_NVME_SC_INTERNAL_DEVICE_ERROR;
2464 				/* Reset the tqpair receving pdu state */
2465 				spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2466 				spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2467 				break;
2468 			}
2469 
2470 			if (!tcp_req->req.data) {
2471 				SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "No buffer allocated for tcp_req(%p) on tqpair(%p\n)",
2472 					      tcp_req, tqpair);
2473 				/* No buffers available. */
2474 				break;
2475 			}
2476 
2477 			TAILQ_REMOVE(&tqpair->ch->pending_data_buf_queue, tcp_req, link);
2478 
2479 			/* If data is transferring from host to controller, we need to do a transfer from the host. */
2480 			if (tcp_req->req.xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
2481 				spdk_nvmf_tcp_pdu_set_buf_from_req(ttransport, tqpair, tcp_req);
2482 				break;
2483 			}
2484 
2485 			spdk_nvmf_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
2486 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_EXECUTE);
2487 			break;
2488 		case TCP_REQUEST_STATE_DATA_PENDING_FOR_R2T:
2489 			spdk_trace_record(TCP_REQUEST_STATE_DATA_PENDING_FOR_R2T, 0, 0,
2490 					  (uintptr_t)tcp_req, 0);
2491 
2492 			if (tqpair->pending_r2t < tqpair->maxr2t) {
2493 				tqpair->pending_r2t++;
2494 				TAILQ_REMOVE(&tqpair->queued_r2t_tcp_req, tcp_req, link);
2495 				spdk_nvmf_tcp_send_r2t_pdu(ttransport, tqpair, tcp_req);
2496 				spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER);
2497 			}
2498 
2499 			break;
2500 
2501 		case TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER:
2502 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_TRANSFERRING_HOST_TO_CONTROLLER, 0, 0,
2503 					  (uintptr_t)tcp_req, 0);
2504 			/* Some external code must kick a request into TCP_REQUEST_STATE_READY_TO_EXECUTE
2505 			 * to escape this state. */
2506 			break;
2507 		case TCP_REQUEST_STATE_READY_TO_EXECUTE:
2508 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_READY_TO_EXECUTE, 0, 0, (uintptr_t)tcp_req, 0);
2509 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTING);
2510 			spdk_nvmf_request_exec(&tcp_req->req);
2511 			break;
2512 		case TCP_REQUEST_STATE_EXECUTING:
2513 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_EXECUTING, 0, 0, (uintptr_t)tcp_req, 0);
2514 			/* Some external code must kick a request into TCP_REQUEST_STATE_EXECUTED
2515 			 * to escape this state. */
2516 			break;
2517 		case TCP_REQUEST_STATE_EXECUTED:
2518 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_EXECUTED, 0, 0, (uintptr_t)tcp_req, 0);
2519 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_READY_TO_COMPLETE);
2520 			break;
2521 		case TCP_REQUEST_STATE_READY_TO_COMPLETE:
2522 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_READY_TO_COMPLETE, 0, 0, (uintptr_t)tcp_req, 0);
2523 			rc = request_transfer_out(&tcp_req->req);
2524 			assert(rc == 0); /* No good way to handle this currently */
2525 			break;
2526 		case TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST:
2527 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_TRANSFERRING_CONTROLLER_TO_HOST, 0, 0,
2528 					  (uintptr_t)tcp_req,
2529 					  0);
2530 			/* Some external code must kick a request into TCP_REQUEST_STATE_COMPLETED
2531 			 * to escape this state. */
2532 			break;
2533 		case TCP_REQUEST_STATE_COMPLETED:
2534 			spdk_trace_record(TRACE_TCP_REQUEST_STATE_COMPLETED, 0, 0, (uintptr_t)tcp_req, 0);
2535 			if (tcp_req->data_from_pool) {
2536 				/* Put the buffer/s back in the pool */
2537 				for (uint32_t i = 0; i < tcp_req->req.iovcnt; i++) {
2538 					spdk_mempool_put(ttransport->data_buf_pool, tcp_req->buffers[i]);
2539 					tcp_req->req.iov[i].iov_base = NULL;
2540 					tcp_req->buffers[i] = NULL;
2541 				}
2542 				tcp_req->data_from_pool = false;
2543 			}
2544 			tcp_req->req.length = 0;
2545 			tcp_req->req.iovcnt = 0;
2546 			tcp_req->req.data = NULL;
2547 			spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_FREE);
2548 			break;
2549 		case TCP_REQUEST_NUM_STATES:
2550 		default:
2551 			assert(0);
2552 			break;
2553 		}
2554 
2555 		if (tcp_req->state != prev_state) {
2556 			progress = true;
2557 		}
2558 	} while (tcp_req->state != prev_state);
2559 
2560 	return progress;
2561 }
2562 
2563 static void
2564 spdk_nvmf_tcp_qpair_process_pending(struct spdk_nvmf_tcp_transport *ttransport,
2565 				    struct nvme_tcp_qpair *tqpair)
2566 {
2567 	struct nvme_tcp_req *tcp_req, *req_tmp;
2568 
2569 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->queued_r2t_tcp_req, link, req_tmp) {
2570 		if (tqpair->pending_r2t < tqpair->maxr2t) {
2571 			if (spdk_nvmf_tcp_req_process(ttransport, tcp_req) == false) {
2572 				break;
2573 			}
2574 		}
2575 	}
2576 
2577 	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->ch->pending_data_buf_queue, link, req_tmp) {
2578 		if (spdk_nvmf_tcp_req_process(ttransport, tcp_req) == false) {
2579 			break;
2580 		}
2581 	}
2582 }
2583 
2584 static void
2585 spdk_nvmf_tcp_sock_cb(void *arg, struct spdk_sock_group *group, struct spdk_sock *sock)
2586 {
2587 	struct nvme_tcp_qpair *tqpair = arg;
2588 	struct spdk_nvmf_tcp_transport *ttransport;
2589 	int rc;
2590 
2591 	assert(tqpair != NULL);
2592 
2593 	if (tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_ERROR) {
2594 		return;
2595 	}
2596 
2597 	ttransport = SPDK_CONTAINEROF(tqpair->qpair.transport, struct spdk_nvmf_tcp_transport, transport);
2598 	spdk_nvmf_tcp_qpair_process_pending(ttransport, tqpair);
2599 
2600 	rc = spdk_nvmf_tcp_sock_process(tqpair);
2601 	if (rc < 0) {
2602 		tqpair->state = NVME_TCP_QPAIR_STATE_EXITING;
2603 		spdk_nvmf_tcp_qpair_flush_pdus(tqpair);
2604 	}
2605 }
2606 
2607 static int
2608 spdk_nvmf_tcp_poll_group_add(struct spdk_nvmf_transport_poll_group *group,
2609 			     struct spdk_nvmf_qpair *qpair)
2610 {
2611 	struct spdk_nvmf_tcp_poll_group	*tgroup;
2612 	struct nvme_tcp_qpair	*tqpair;
2613 	int				rc;
2614 
2615 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2616 	tqpair = SPDK_CONTAINEROF(qpair, struct nvme_tcp_qpair, qpair);
2617 
2618 	rc = spdk_sock_group_add_sock(tgroup->sock_group, tqpair->sock,
2619 				      spdk_nvmf_tcp_sock_cb, tqpair);
2620 	if (rc != 0) {
2621 		SPDK_ERRLOG("Could not add sock to sock_group: %s (%d)\n",
2622 			    spdk_strerror(errno), errno);
2623 		spdk_nvmf_tcp_qpair_destroy(tqpair);
2624 		return -1;
2625 	}
2626 
2627 	rc =  spdk_nvmf_tcp_qpair_sock_init(tqpair);
2628 	if (rc != 0) {
2629 		SPDK_ERRLOG("Cannot set sock opt for tqpair=%p\n", tqpair);
2630 		spdk_nvmf_tcp_qpair_destroy(tqpair);
2631 		return -1;
2632 	}
2633 
2634 	rc = spdk_nvmf_tcp_qpair_init(&tqpair->qpair);
2635 	if (rc < 0) {
2636 		SPDK_ERRLOG("Cannot init tqpair=%p\n", tqpair);
2637 		spdk_nvmf_tcp_qpair_destroy(tqpair);
2638 		return -1;
2639 	}
2640 
2641 	rc = spdk_nvmf_tcp_qpair_init_mem_resource(tqpair, 1);
2642 	if (rc < 0) {
2643 		SPDK_ERRLOG("Cannot init memory resource info for tqpair=%p\n", tqpair);
2644 		spdk_nvmf_tcp_qpair_destroy(tqpair);
2645 		return -1;
2646 	}
2647 
2648 	tqpair->state = NVME_TCP_QPAIR_STATE_INVALID;
2649 	tqpair->timeout = SPDK_NVME_TCP_QPAIR_EXIT_TIMEOUT;
2650 	tqpair->last_pdu_time = spdk_get_ticks();
2651 
2652 	tqpair->tgroup = tgroup;
2653 	TAILQ_INSERT_TAIL(&tgroup->qpairs, tqpair, link);
2654 
2655 	return 0;
2656 }
2657 
2658 static int
2659 spdk_nvmf_tcp_req_complete(struct spdk_nvmf_request *req)
2660 {
2661 	struct spdk_nvmf_tcp_transport *ttransport;
2662 	struct nvme_tcp_req *tcp_req;
2663 
2664 	ttransport = SPDK_CONTAINEROF(req->qpair->transport, struct spdk_nvmf_tcp_transport, transport);
2665 	tcp_req = SPDK_CONTAINEROF(req, struct nvme_tcp_req, req);
2666 
2667 	spdk_nvmf_tcp_req_set_state(tcp_req, TCP_REQUEST_STATE_EXECUTED);
2668 	spdk_nvmf_tcp_req_process(ttransport, tcp_req);
2669 
2670 	return 0;
2671 }
2672 
2673 static void
2674 spdk_nvmf_tcp_close_qpair(struct spdk_nvmf_qpair *qpair)
2675 {
2676 	SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "enter\n");
2677 
2678 	spdk_nvmf_tcp_qpair_destroy(SPDK_CONTAINEROF(qpair, struct nvme_tcp_qpair, qpair));
2679 }
2680 
2681 static void
2682 spdk_nvmf_tcp_qpair_handle_timout(struct nvme_tcp_qpair *tqpair)
2683 {
2684 	uint64_t	tsc;
2685 
2686 	if ((tqpair->state == NVME_TCP_QPAIR_STATE_EXITING) ||
2687 	    (tqpair->state == NVME_TCP_QPAIR_STATE_EXITED)) {
2688 		return;
2689 	}
2690 
2691 	/* Currently, we did not have keep alive support, so make sure that we should have the generic support later */
2692 	if (tqpair->recv_state != NVME_TCP_PDU_RECV_STATE_ERROR) {
2693 		return;
2694 	}
2695 
2696 	/* Check for interval expiration */
2697 	tsc = spdk_get_ticks();
2698 	if ((tsc - tqpair->last_pdu_time) > (tqpair->timeout  * spdk_get_ticks_hz())) {
2699 		SPDK_ERRLOG("No pdu coming for tqpair=%p within %d seconds\n", tqpair, tqpair->timeout);
2700 		tqpair->state = NVME_TCP_QPAIR_STATE_EXITING;
2701 	}
2702 }
2703 
2704 static int
2705 spdk_nvmf_tcp_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
2706 {
2707 	struct spdk_nvmf_tcp_poll_group *tgroup;
2708 	struct nvme_tcp_qpair *tqpair, *tmp;
2709 	int rc;
2710 
2711 	tgroup = SPDK_CONTAINEROF(group, struct spdk_nvmf_tcp_poll_group, group);
2712 
2713 	if (spdk_unlikely(TAILQ_EMPTY(&tgroup->qpairs))) {
2714 		return 0;
2715 	}
2716 
2717 	rc = spdk_sock_group_poll(tgroup->sock_group);
2718 	if (rc < 0) {
2719 		SPDK_ERRLOG("Failed to poll sock_group=%p\n", tgroup->sock_group);
2720 		return rc;
2721 	}
2722 
2723 
2724 	TAILQ_FOREACH_SAFE(tqpair, &tgroup->qpairs, link, tmp) {
2725 		spdk_nvmf_tcp_qpair_handle_timout(tqpair);
2726 		if (tqpair->state == NVME_TCP_QPAIR_STATE_EXITING) {
2727 			/* to prevent the state is set again */
2728 			tqpair->state = NVME_TCP_QPAIR_STATE_EXITED;
2729 			SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "will disconect the tqpair=%p\n", tqpair);
2730 			spdk_nvmf_qpair_disconnect(&tqpair->qpair, NULL, NULL);
2731 		}
2732 	}
2733 
2734 	return 0;
2735 }
2736 
2737 static bool
2738 spdk_nvmf_tcp_qpair_is_idle(struct spdk_nvmf_qpair *qpair)
2739 {
2740 	struct nvme_tcp_qpair *tqpair;
2741 
2742 	tqpair = SPDK_CONTAINEROF(qpair, struct nvme_tcp_qpair, qpair);
2743 	if (tqpair->state_cntr[TCP_REQUEST_STATE_FREE] == tqpair->max_queue_depth) {
2744 		return true;
2745 	}
2746 
2747 	return false;
2748 }
2749 
2750 static int
2751 spdk_nvmf_tcp_qpair_get_trid(struct spdk_nvmf_qpair *qpair,
2752 			     struct spdk_nvme_transport_id *trid, bool peer)
2753 {
2754 	struct nvme_tcp_qpair     *tqpair;
2755 	uint16_t			port;
2756 
2757 	tqpair = SPDK_CONTAINEROF(qpair, struct nvme_tcp_qpair, qpair);
2758 	trid->trtype = SPDK_NVME_TRANSPORT_TCP;
2759 
2760 	if (peer) {
2761 		snprintf(trid->traddr, sizeof(trid->traddr), "%s", tqpair->initiator_addr);
2762 		port = tqpair->initiator_port;
2763 	} else {
2764 		snprintf(trid->traddr, sizeof(trid->traddr), "%s", tqpair->target_addr);
2765 		port = tqpair->target_port;
2766 	}
2767 
2768 	if (spdk_sock_is_ipv4(tqpair->sock)) {
2769 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV4;
2770 	} else if (spdk_sock_is_ipv4(tqpair->sock)) {
2771 		trid->adrfam = SPDK_NVMF_ADRFAM_IPV6;
2772 	} else {
2773 		return -1;
2774 	}
2775 
2776 	snprintf(trid->trsvcid, sizeof(trid->trsvcid), "%d", port);
2777 	return 0;
2778 }
2779 
2780 static int
2781 spdk_nvmf_tcp_qpair_get_local_trid(struct spdk_nvmf_qpair *qpair,
2782 				   struct spdk_nvme_transport_id *trid)
2783 {
2784 	return spdk_nvmf_tcp_qpair_get_trid(qpair, trid, 0);
2785 }
2786 
2787 static int
2788 spdk_nvmf_tcp_qpair_get_peer_trid(struct spdk_nvmf_qpair *qpair,
2789 				  struct spdk_nvme_transport_id *trid)
2790 {
2791 	return spdk_nvmf_tcp_qpair_get_trid(qpair, trid, 1);
2792 }
2793 
2794 static int
2795 spdk_nvmf_tcp_qpair_get_listen_trid(struct spdk_nvmf_qpair *qpair,
2796 				    struct spdk_nvme_transport_id *trid)
2797 {
2798 	return spdk_nvmf_tcp_qpair_get_trid(qpair, trid, 0);
2799 }
2800 
2801 static int
2802 spdk_nvmf_tcp_qpair_set_sq_size(struct spdk_nvmf_qpair *qpair)
2803 {
2804 	struct nvme_tcp_qpair     *tqpair;
2805 	int rc;
2806 	tqpair = SPDK_CONTAINEROF(qpair, struct nvme_tcp_qpair, qpair);
2807 
2808 	rc = spdk_nvmf_tcp_qpair_init_mem_resource(tqpair, tqpair->qpair.sq_head_max);
2809 	if (!rc) {
2810 		tqpair->max_queue_depth += tqpair->qpair.sq_head_max;
2811 		tqpair->free_pdu_num += tqpair->qpair.sq_head_max;
2812 		tqpair->state_cntr[TCP_REQUEST_STATE_FREE] += tqpair->qpair.sq_head_max;
2813 		SPDK_DEBUGLOG(SPDK_LOG_NVMF_TCP, "The queue depth=%u for tqpair=%p\n",
2814 			      tqpair->max_queue_depth, tqpair);
2815 	}
2816 
2817 	return rc;
2818 
2819 }
2820 
2821 #define SPDK_NVMF_TCP_DEFAULT_MAX_QUEUE_DEPTH 128
2822 #define SPDK_NVMF_TCP_DEFAULT_AQ_DEPTH 128
2823 #define SPDK_NVMF_TCP_DEFAULT_MAX_QPAIRS_PER_CTRLR 64
2824 #define SPDK_NVMF_TCP_DEFAULT_IN_CAPSULE_DATA_SIZE 4096
2825 #define SPDK_NVMF_TCP_DEFAULT_MAX_IO_SIZE 131072
2826 #define SPDK_NVMF_TCP_DEFAULT_IO_UNIT_SIZE 131072
2827 
2828 static void
2829 spdk_nvmf_tcp_opts_init(struct spdk_nvmf_transport_opts *opts)
2830 {
2831 	opts->max_queue_depth =      SPDK_NVMF_TCP_DEFAULT_MAX_QUEUE_DEPTH;
2832 	opts->max_qpairs_per_ctrlr = SPDK_NVMF_TCP_DEFAULT_MAX_QPAIRS_PER_CTRLR;
2833 	opts->in_capsule_data_size = SPDK_NVMF_TCP_DEFAULT_IN_CAPSULE_DATA_SIZE;
2834 	opts->max_io_size =          SPDK_NVMF_TCP_DEFAULT_MAX_IO_SIZE;
2835 	opts->io_unit_size =         SPDK_NVMF_TCP_DEFAULT_IO_UNIT_SIZE;
2836 	opts->max_aq_depth =         SPDK_NVMF_TCP_DEFAULT_AQ_DEPTH;
2837 }
2838 
2839 const struct spdk_nvmf_transport_ops spdk_nvmf_transport_tcp = {
2840 	.type = SPDK_NVME_TRANSPORT_TCP,
2841 	.opts_init = spdk_nvmf_tcp_opts_init,
2842 	.create = spdk_nvmf_tcp_create,
2843 	.destroy = spdk_nvmf_tcp_destroy,
2844 
2845 	.listen = spdk_nvmf_tcp_listen,
2846 	.stop_listen = spdk_nvmf_tcp_stop_listen,
2847 	.accept = spdk_nvmf_tcp_accept,
2848 
2849 	.listener_discover = spdk_nvmf_tcp_discover,
2850 
2851 	.poll_group_create = spdk_nvmf_tcp_poll_group_create,
2852 	.poll_group_destroy = spdk_nvmf_tcp_poll_group_destroy,
2853 	.poll_group_add = spdk_nvmf_tcp_poll_group_add,
2854 	.poll_group_poll = spdk_nvmf_tcp_poll_group_poll,
2855 
2856 	.req_free = spdk_nvmf_tcp_req_free,
2857 	.req_complete = spdk_nvmf_tcp_req_complete,
2858 
2859 	.qpair_fini = spdk_nvmf_tcp_close_qpair,
2860 	.qpair_is_idle = spdk_nvmf_tcp_qpair_is_idle,
2861 	.qpair_get_local_trid = spdk_nvmf_tcp_qpair_get_local_trid,
2862 	.qpair_get_peer_trid = spdk_nvmf_tcp_qpair_get_peer_trid,
2863 	.qpair_get_listen_trid = spdk_nvmf_tcp_qpair_get_listen_trid,
2864 	.qpair_set_sqsize = spdk_nvmf_tcp_qpair_set_sq_size,
2865 };
2866 
2867 SPDK_LOG_REGISTER_COMPONENT("nvmf_tcp", SPDK_LOG_NVMF_TCP)
2868