Adding upstream version 18.2.2.upstream/18.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1973 insertions, 0 deletions

diff --git a/src/spdk/lib/nvme/nvme_tcp.c b/src/spdk/lib/nvme/nvme_tcp.c
new file mode 100644
index 000000000..98e8c6827
--- /dev/null
+++ b/src/spdk/lib/nvme/nvme_tcp.c
@@ -0,0 +1,1973 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright (c) Intel Corporation. All rights reserved.
+ *   Copyright (c) 2020 Mellanox Technologies LTD. All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * NVMe/TCP transport
+ */
+
+#include "nvme_internal.h"
+
+#include "spdk/endian.h"
+#include "spdk/likely.h"
+#include "spdk/string.h"
+#include "spdk/stdinc.h"
+#include "spdk/crc32.h"
+#include "spdk/endian.h"
+#include "spdk/assert.h"
+#include "spdk/string.h"
+#include "spdk/thread.h"
+#include "spdk/trace.h"
+#include "spdk/util.h"
+
+#include "spdk_internal/nvme_tcp.h"
+
+#define NVME_TCP_RW_BUFFER_SIZE 131072
+#define NVME_TCP_TIME_OUT_IN_SECONDS 2
+
+#define NVME_TCP_HPDA_DEFAULT			0
+#define NVME_TCP_MAX_R2T_DEFAULT		1
+#define NVME_TCP_PDU_H2C_MIN_DATA_SIZE		4096
+#define NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE	8192
+
+/* NVMe TCP transport extensions for spdk_nvme_ctrlr */
+struct nvme_tcp_ctrlr {
+	struct spdk_nvme_ctrlr			ctrlr;
+};
+
+struct nvme_tcp_poll_group {
+	struct spdk_nvme_transport_poll_group group;
+	struct spdk_sock_group *sock_group;
+	uint32_t completions_per_qpair;
+	int64_t num_completions;
+};
+
+/* NVMe TCP qpair extensions for spdk_nvme_qpair */
+struct nvme_tcp_qpair {
+	struct spdk_nvme_qpair			qpair;
+	struct spdk_sock			*sock;
+
+	TAILQ_HEAD(, nvme_tcp_req)		free_reqs;
+	TAILQ_HEAD(, nvme_tcp_req)		outstanding_reqs;
+
+	TAILQ_HEAD(, nvme_tcp_pdu)		send_queue;
+	struct nvme_tcp_pdu			recv_pdu;
+	struct nvme_tcp_pdu			send_pdu; /* only for error pdu and init pdu */
+	struct nvme_tcp_pdu			*send_pdus; /* Used by tcp_reqs */
+	enum nvme_tcp_pdu_recv_state		recv_state;
+
+	struct nvme_tcp_req			*tcp_reqs;
+
+	uint16_t				num_entries;
+
+	bool					host_hdgst_enable;
+	bool					host_ddgst_enable;
+
+	/** Specifies the maximum number of PDU-Data bytes per H2C Data Transfer PDU */
+	uint32_t				maxh2cdata;
+
+	uint32_t				maxr2t;
+
+	/* 0 based value, which is used to guide the padding */
+	uint8_t					cpda;
+
+	enum nvme_tcp_qpair_state		state;
+};
+
+enum nvme_tcp_req_state {
+	NVME_TCP_REQ_FREE,
+	NVME_TCP_REQ_ACTIVE,
+	NVME_TCP_REQ_ACTIVE_R2T,
+};
+
+struct nvme_tcp_req {
+	struct nvme_request			*req;
+	enum nvme_tcp_req_state			state;
+	uint16_t				cid;
+	uint16_t				ttag;
+	uint32_t				datao;
+	uint32_t				r2tl_remain;
+	uint32_t				active_r2ts;
+	bool					in_capsule_data;
+	/* It is used to track whether the req can be safely freed */
+	struct {
+		uint8_t				send_ack : 1;
+		uint8_t				data_recv : 1;
+		uint8_t				r2t_recv : 1;
+		uint8_t				reserved : 5;
+	} ordering;
+	struct nvme_tcp_pdu			*send_pdu;
+	struct iovec				iov[NVME_TCP_MAX_SGL_DESCRIPTORS];
+	uint32_t				iovcnt;
+	struct nvme_tcp_qpair			*tqpair;
+	TAILQ_ENTRY(nvme_tcp_req)		link;
+};
+
+static void nvme_tcp_send_h2c_data(struct nvme_tcp_req *tcp_req);
+
+static inline struct nvme_tcp_qpair *
+nvme_tcp_qpair(struct spdk_nvme_qpair *qpair)
+{
+	assert(qpair->trtype == SPDK_NVME_TRANSPORT_TCP);
+	return SPDK_CONTAINEROF(qpair, struct nvme_tcp_qpair, qpair);
+}
+
+static inline struct nvme_tcp_poll_group *
+nvme_tcp_poll_group(struct spdk_nvme_transport_poll_group *group)
+{
+	return SPDK_CONTAINEROF(group, struct nvme_tcp_poll_group, group);
+}
+
+static inline struct nvme_tcp_ctrlr *
+nvme_tcp_ctrlr(struct spdk_nvme_ctrlr *ctrlr)
+{
+	assert(ctrlr->trid.trtype == SPDK_NVME_TRANSPORT_TCP);
+	return SPDK_CONTAINEROF(ctrlr, struct nvme_tcp_ctrlr, ctrlr);
+}
+
+static struct nvme_tcp_req *
+nvme_tcp_req_get(struct nvme_tcp_qpair *tqpair)
+{
+	struct nvme_tcp_req *tcp_req;
+
+	tcp_req = TAILQ_FIRST(&tqpair->free_reqs);
+	if (!tcp_req) {
+		return NULL;
+	}
+
+	assert(tcp_req->state == NVME_TCP_REQ_FREE);
+	tcp_req->state = NVME_TCP_REQ_ACTIVE;
+	TAILQ_REMOVE(&tqpair->free_reqs, tcp_req, link);
+	tcp_req->datao = 0;
+	tcp_req->req = NULL;
+	tcp_req->in_capsule_data = false;
+	tcp_req->r2tl_remain = 0;
+	tcp_req->active_r2ts = 0;
+	tcp_req->iovcnt = 0;
+	tcp_req->ordering.send_ack = 0;
+	tcp_req->ordering.data_recv = 0;
+	tcp_req->ordering.r2t_recv = 0;
+	memset(tcp_req->send_pdu, 0, sizeof(struct nvme_tcp_pdu));
+	TAILQ_INSERT_TAIL(&tqpair->outstanding_reqs, tcp_req, link);
+
+	return tcp_req;
+}
+
+static void
+nvme_tcp_req_put(struct nvme_tcp_qpair *tqpair, struct nvme_tcp_req *tcp_req)
+{
+	assert(tcp_req->state != NVME_TCP_REQ_FREE);
+	tcp_req->state = NVME_TCP_REQ_FREE;
+	TAILQ_INSERT_HEAD(&tqpair->free_reqs, tcp_req, link);
+}
+
+static int
+nvme_tcp_parse_addr(struct sockaddr_storage *sa, int family, const char *addr, const char *service)
+{
+	struct addrinfo *res;
+	struct addrinfo hints;
+	int ret;
+
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = family;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_protocol = 0;
+
+	ret = getaddrinfo(addr, service, &hints, &res);
+	if (ret) {
+		SPDK_ERRLOG("getaddrinfo failed: %s (%d)\n", gai_strerror(ret), ret);
+		return ret;
+	}
+
+	if (res->ai_addrlen > sizeof(*sa)) {
+		SPDK_ERRLOG("getaddrinfo() ai_addrlen %zu too large\n", (size_t)res->ai_addrlen);
+		ret = EINVAL;
+	} else {
+		memcpy(sa, res->ai_addr, res->ai_addrlen);
+	}
+
+	freeaddrinfo(res);
+	return ret;
+}
+
+static void
+nvme_tcp_free_reqs(struct nvme_tcp_qpair *tqpair)
+{
+	free(tqpair->tcp_reqs);
+	tqpair->tcp_reqs = NULL;
+
+	spdk_free(tqpair->send_pdus);
+	tqpair->send_pdus = NULL;
+}
+
+static int
+nvme_tcp_alloc_reqs(struct nvme_tcp_qpair *tqpair)
+{
+	uint16_t i;
+	struct nvme_tcp_req	*tcp_req;
+
+	tqpair->tcp_reqs = calloc(tqpair->num_entries, sizeof(struct nvme_tcp_req));
+	if (tqpair->tcp_reqs == NULL) {
+		SPDK_ERRLOG("Failed to allocate tcp_reqs on tqpair=%p\n", tqpair);
+		goto fail;
+	}
+
+	tqpair->send_pdus = spdk_zmalloc(tqpair->num_entries * sizeof(struct nvme_tcp_pdu),
+					 0x1000, NULL,
+					 SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
+
+	if (tqpair->send_pdus == NULL) {
+		SPDK_ERRLOG("Failed to allocate send_pdus on tqpair=%p\n", tqpair);
+		goto fail;
+	}
+
+	TAILQ_INIT(&tqpair->send_queue);
+	TAILQ_INIT(&tqpair->free_reqs);
+	TAILQ_INIT(&tqpair->outstanding_reqs);
+	for (i = 0; i < tqpair->num_entries; i++) {
+		tcp_req = &tqpair->tcp_reqs[i];
+		tcp_req->cid = i;
+		tcp_req->tqpair = tqpair;
+		tcp_req->send_pdu = &tqpair->send_pdus[i];
+		TAILQ_INSERT_TAIL(&tqpair->free_reqs, tcp_req, link);
+	}
+
+	return 0;
+fail:
+	nvme_tcp_free_reqs(tqpair);
+	return -ENOMEM;
+}
+
+static void
+nvme_tcp_ctrlr_disconnect_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
+{
+	struct nvme_tcp_qpair *tqpair = nvme_tcp_qpair(qpair);
+	struct nvme_tcp_pdu *pdu;
+
+	spdk_sock_close(&tqpair->sock);
+
+	/* clear the send_queue */
+	while (!TAILQ_EMPTY(&tqpair->send_queue)) {
+		pdu = TAILQ_FIRST(&tqpair->send_queue);
+		/* Remove the pdu from the send_queue to prevent the wrong sending out
+		 * in the next round connection
+		 */
+		TAILQ_REMOVE(&tqpair->send_queue, pdu, tailq);
+	}
+}
+
+static void nvme_tcp_qpair_abort_reqs(struct spdk_nvme_qpair *qpair, uint32_t dnr);
+
+static int
+nvme_tcp_ctrlr_delete_io_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
+{
+	struct nvme_tcp_qpair *tqpair;
+
+	if (!qpair) {
+		return -1;
+	}
+
+	nvme_transport_ctrlr_disconnect_qpair(ctrlr, qpair);
+	nvme_tcp_qpair_abort_reqs(qpair, 1);
+	nvme_qpair_deinit(qpair);
+	tqpair = nvme_tcp_qpair(qpair);
+	nvme_tcp_free_reqs(tqpair);
+	free(tqpair);
+
+	return 0;
+}
+
+static int
+nvme_tcp_ctrlr_enable(struct spdk_nvme_ctrlr *ctrlr)
+{
+	return 0;
+}
+
+static int
+nvme_tcp_ctrlr_destruct(struct spdk_nvme_ctrlr *ctrlr)
+{
+	struct nvme_tcp_ctrlr *tctrlr = nvme_tcp_ctrlr(ctrlr);
+
+	if (ctrlr->adminq) {
+		nvme_tcp_ctrlr_delete_io_qpair(ctrlr, ctrlr->adminq);
+	}
+
+	nvme_ctrlr_destruct_finish(ctrlr);
+
+	free(tctrlr);
+
+	return 0;
+}
+
+static void
+_pdu_write_done(void *cb_arg, int err)
+{
+	struct nvme_tcp_pdu *pdu = cb_arg;
+	struct nvme_tcp_qpair *tqpair = pdu->qpair;
+
+	TAILQ_REMOVE(&tqpair->send_queue, pdu, tailq);
+
+	if (err != 0) {
+		nvme_transport_ctrlr_disconnect_qpair(tqpair->qpair.ctrlr, &tqpair->qpair);
+		return;
+	}
+
+	assert(pdu->cb_fn != NULL);
+	pdu->cb_fn(pdu->cb_arg);
+}
+
+static int
+nvme_tcp_qpair_write_pdu(struct nvme_tcp_qpair *tqpair,
+			 struct nvme_tcp_pdu *pdu,
+			 nvme_tcp_qpair_xfer_complete_cb cb_fn,
+			 void *cb_arg)
+{
+	int hlen;
+	uint32_t crc32c;
+	uint32_t mapped_length = 0;
+
+	hlen = pdu->hdr.common.hlen;
+
+	/* Header Digest */
+	if (g_nvme_tcp_hdgst[pdu->hdr.common.pdu_type] && tqpair->host_hdgst_enable) {
+		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
+		MAKE_DIGEST_WORD((uint8_t *)pdu->hdr.raw + hlen, crc32c);
+	}
+
+	/* Data Digest */
+	if (pdu->data_len > 0 && g_nvme_tcp_ddgst[pdu->hdr.common.pdu_type] && tqpair->host_ddgst_enable) {
+		crc32c = nvme_tcp_pdu_calc_data_digest(pdu);
+		MAKE_DIGEST_WORD(pdu->data_digest, crc32c);
+	}
+
+	pdu->cb_fn = cb_fn;
+	pdu->cb_arg = cb_arg;
+
+	pdu->sock_req.iovcnt = nvme_tcp_build_iovs(pdu->iov, NVME_TCP_MAX_SGL_DESCRIPTORS, pdu,
+			       tqpair->host_hdgst_enable, tqpair->host_ddgst_enable,
+			       &mapped_length);
+	pdu->qpair = tqpair;
+	pdu->sock_req.cb_fn = _pdu_write_done;
+	pdu->sock_req.cb_arg = pdu;
+	TAILQ_INSERT_TAIL(&tqpair->send_queue, pdu, tailq);
+	spdk_sock_writev_async(tqpair->sock, &pdu->sock_req);
+
+	return 0;
+}
+
+/*
+ * Build SGL describing contiguous payload buffer.
+ */
+static int
+nvme_tcp_build_contig_request(struct nvme_tcp_qpair *tqpair, struct nvme_tcp_req *tcp_req)
+{
+	struct nvme_request *req = tcp_req->req;
+
+	tcp_req->iov[0].iov_base = req->payload.contig_or_cb_arg + req->payload_offset;
+	tcp_req->iov[0].iov_len = req->payload_size;
+	tcp_req->iovcnt = 1;
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "enter\n");
+
+	assert(nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_CONTIG);
+
+	return 0;
+}
+
+/*
+ * Build SGL describing scattered payload buffer.
+ */
+static int
+nvme_tcp_build_sgl_request(struct nvme_tcp_qpair *tqpair, struct nvme_tcp_req *tcp_req)
+{
+	int rc;
+	uint32_t length, remaining_size, iovcnt = 0, max_num_sgl;
+	struct nvme_request *req = tcp_req->req;
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "enter\n");
+
+	assert(req->payload_size != 0);
+	assert(nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_SGL);
+	assert(req->payload.reset_sgl_fn != NULL);
+	assert(req->payload.next_sge_fn != NULL);
+	req->payload.reset_sgl_fn(req->payload.contig_or_cb_arg, req->payload_offset);
+
+	max_num_sgl = spdk_min(req->qpair->ctrlr->max_sges, NVME_TCP_MAX_SGL_DESCRIPTORS);
+	remaining_size = req->payload_size;
+
+	do {
+		rc = req->payload.next_sge_fn(req->payload.contig_or_cb_arg, &tcp_req->iov[iovcnt].iov_base,
+					      &length);
+		if (rc) {
+			return -1;
+		}
+
+		length = spdk_min(length, remaining_size);
+		tcp_req->iov[iovcnt].iov_len = length;
+		remaining_size -= length;
+		iovcnt++;
+	} while (remaining_size > 0 && iovcnt < max_num_sgl);
+
+
+	/* Should be impossible if we did our sgl checks properly up the stack, but do a sanity check here. */
+	if (remaining_size > 0) {
+		SPDK_ERRLOG("Failed to construct tcp_req=%p, and the iovcnt=%u, remaining_size=%u\n",
+			    tcp_req, iovcnt, remaining_size);
+		return -1;
+	}
+
+	tcp_req->iovcnt = iovcnt;
+
+	return 0;
+}
+
+static int
+nvme_tcp_req_init(struct nvme_tcp_qpair *tqpair, struct nvme_request *req,
+		  struct nvme_tcp_req *tcp_req)
+{
+	struct spdk_nvme_ctrlr *ctrlr = tqpair->qpair.ctrlr;
+	int rc = 0;
+	enum spdk_nvme_data_transfer xfer;
+	uint32_t max_incapsule_data_size;
+
+	tcp_req->req = req;
+	req->cmd.cid = tcp_req->cid;
+	req->cmd.psdt = SPDK_NVME_PSDT_SGL_MPTR_CONTIG;
+	req->cmd.dptr.sgl1.unkeyed.type = SPDK_NVME_SGL_TYPE_TRANSPORT_DATA_BLOCK;
+	req->cmd.dptr.sgl1.unkeyed.subtype = SPDK_NVME_SGL_SUBTYPE_TRANSPORT;
+	req->cmd.dptr.sgl1.unkeyed.length = req->payload_size;
+
+	if (nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_CONTIG) {
+		rc = nvme_tcp_build_contig_request(tqpair, tcp_req);
+	} else if (nvme_payload_type(&req->payload) == NVME_PAYLOAD_TYPE_SGL) {
+		rc = nvme_tcp_build_sgl_request(tqpair, tcp_req);
+	} else {
+		rc = -1;
+	}
+
+	if (rc) {
+		return rc;
+	}
+
+	if (req->cmd.opc == SPDK_NVME_OPC_FABRIC) {
+		struct spdk_nvmf_capsule_cmd *nvmf_cmd = (struct spdk_nvmf_capsule_cmd *)&req->cmd;
+
+		xfer = spdk_nvme_opc_get_data_transfer(nvmf_cmd->fctype);
+	} else {
+		xfer = spdk_nvme_opc_get_data_transfer(req->cmd.opc);
+	}
+	if (xfer == SPDK_NVME_DATA_HOST_TO_CONTROLLER) {
+		max_incapsule_data_size = ctrlr->ioccsz_bytes;
+		if ((req->cmd.opc == SPDK_NVME_OPC_FABRIC) || nvme_qpair_is_admin_queue(&tqpair->qpair)) {
+			max_incapsule_data_size = spdk_min(max_incapsule_data_size, NVME_TCP_IN_CAPSULE_DATA_MAX_SIZE);
+		}
+
+		if (req->payload_size <= max_incapsule_data_size) {
+			req->cmd.dptr.sgl1.unkeyed.type = SPDK_NVME_SGL_TYPE_DATA_BLOCK;
+			req->cmd.dptr.sgl1.unkeyed.subtype = SPDK_NVME_SGL_SUBTYPE_OFFSET;
+			req->cmd.dptr.sgl1.address = 0;
+			tcp_req->in_capsule_data = true;
+		}
+	}
+
+	return 0;
+}
+
+static inline void
+nvme_tcp_req_put_safe(struct nvme_tcp_req *tcp_req)
+{
+	if (tcp_req->ordering.send_ack && tcp_req->ordering.data_recv) {
+		assert(tcp_req->state == NVME_TCP_REQ_ACTIVE);
+		assert(tcp_req->tqpair != NULL);
+		nvme_tcp_req_put(tcp_req->tqpair, tcp_req);
+	}
+}
+
+static void
+nvme_tcp_qpair_cmd_send_complete(void *cb_arg)
+{
+	struct nvme_tcp_req *tcp_req = cb_arg;
+
+	tcp_req->ordering.send_ack = 1;
+	/* Handle the r2t case */
+	if (spdk_unlikely(tcp_req->ordering.r2t_recv)) {
+		nvme_tcp_send_h2c_data(tcp_req);
+	} else {
+		nvme_tcp_req_put_safe(tcp_req);
+	}
+}
+
+static int
+nvme_tcp_qpair_capsule_cmd_send(struct nvme_tcp_qpair *tqpair,
+				struct nvme_tcp_req *tcp_req)
+{
+	struct nvme_tcp_pdu *pdu;
+	struct spdk_nvme_tcp_cmd *capsule_cmd;
+	uint32_t plen = 0, alignment;
+	uint8_t pdo;
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "enter\n");
+	pdu = tcp_req->send_pdu;
+
+	capsule_cmd = &pdu->hdr.capsule_cmd;
+	capsule_cmd->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_CAPSULE_CMD;
+	plen = capsule_cmd->common.hlen = sizeof(*capsule_cmd);
+	capsule_cmd->ccsqe = tcp_req->req->cmd;
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "capsule_cmd cid=%u on tqpair(%p)\n", tcp_req->req->cmd.cid, tqpair);
+
+	if (tqpair->host_hdgst_enable) {
+		SPDK_DEBUGLOG(SPDK_LOG_NVME, "Header digest is enabled for capsule command on tcp_req=%p\n",
+			      tcp_req);
+		capsule_cmd->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
+		plen += SPDK_NVME_TCP_DIGEST_LEN;
+	}
+
+	if ((tcp_req->req->payload_size == 0) || !tcp_req->in_capsule_data) {
+		goto end;
+	}
+
+	pdo = plen;
+	pdu->padding_len = 0;
+	if (tqpair->cpda) {
+		alignment = (tqpair->cpda + 1) << 2;
+		if (alignment > plen) {
+			pdu->padding_len = alignment - plen;
+			pdo = alignment;
+			plen = alignment;
+		}
+	}
+
+	capsule_cmd->common.pdo = pdo;
+	plen += tcp_req->req->payload_size;
+	if (tqpair->host_ddgst_enable) {
+		capsule_cmd->common.flags |= SPDK_NVME_TCP_CH_FLAGS_DDGSTF;
+		plen += SPDK_NVME_TCP_DIGEST_LEN;
+	}
+
+	tcp_req->datao = 0;
+	nvme_tcp_pdu_set_data_buf(pdu, tcp_req->iov, tcp_req->iovcnt,
+				  0, tcp_req->req->payload_size);
+end:
+	capsule_cmd->common.plen = plen;
+	return nvme_tcp_qpair_write_pdu(tqpair, pdu, nvme_tcp_qpair_cmd_send_complete, tcp_req);
+
+}
+
+static int
+nvme_tcp_qpair_submit_request(struct spdk_nvme_qpair *qpair,
+			      struct nvme_request *req)
+{
+	struct nvme_tcp_qpair *tqpair;
+	struct nvme_tcp_req *tcp_req;
+
+	tqpair = nvme_tcp_qpair(qpair);
+	assert(tqpair != NULL);
+	assert(req != NULL);
+
+	tcp_req = nvme_tcp_req_get(tqpair);
+	if (!tcp_req) {
+		/* Inform the upper layer to try again later. */
+		return -EAGAIN;
+	}
+
+	if (nvme_tcp_req_init(tqpair, req, tcp_req)) {
+		SPDK_ERRLOG("nvme_tcp_req_init() failed\n");
+		TAILQ_REMOVE(&tcp_req->tqpair->outstanding_reqs, tcp_req, link);
+		nvme_tcp_req_put(tqpair, tcp_req);
+		return -1;
+	}
+
+	return nvme_tcp_qpair_capsule_cmd_send(tqpair, tcp_req);
+}
+
+static int
+nvme_tcp_qpair_reset(struct spdk_nvme_qpair *qpair)
+{
+	return 0;
+}
+
+static void
+nvme_tcp_req_complete(struct nvme_tcp_req *tcp_req,
+		      struct spdk_nvme_cpl *rsp)
+{
+	struct nvme_request *req;
+
+	assert(tcp_req->req != NULL);
+	req = tcp_req->req;
+
+	TAILQ_REMOVE(&tcp_req->tqpair->outstanding_reqs, tcp_req, link);
+	nvme_complete_request(req->cb_fn, req->cb_arg, req->qpair, req, rsp);
+	nvme_free_request(req);
+}
+
+static void
+nvme_tcp_qpair_abort_reqs(struct spdk_nvme_qpair *qpair, uint32_t dnr)
+{
+	struct nvme_tcp_req *tcp_req, *tmp;
+	struct spdk_nvme_cpl cpl;
+	struct nvme_tcp_qpair *tqpair = nvme_tcp_qpair(qpair);
+
+	cpl.status.sc = SPDK_NVME_SC_ABORTED_SQ_DELETION;
+	cpl.status.sct = SPDK_NVME_SCT_GENERIC;
+	cpl.status.dnr = dnr;
+
+	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->outstanding_reqs, link, tmp) {
+		nvme_tcp_req_complete(tcp_req, &cpl);
+		nvme_tcp_req_put(tqpair, tcp_req);
+	}
+}
+
+static void
+nvme_tcp_qpair_set_recv_state(struct nvme_tcp_qpair *tqpair,
+			      enum nvme_tcp_pdu_recv_state state)
+{
+	if (tqpair->recv_state == state) {
+		SPDK_ERRLOG("The recv state of tqpair=%p is same with the state(%d) to be set\n",
+			    tqpair, state);
+		return;
+	}
+
+	tqpair->recv_state = state;
+	switch (state) {
+	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY:
+	case NVME_TCP_PDU_RECV_STATE_ERROR:
+		memset(&tqpair->recv_pdu, 0, sizeof(struct nvme_tcp_pdu));
+		break;
+	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH:
+	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH:
+	case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:
+	default:
+		break;
+	}
+}
+
+static void
+nvme_tcp_qpair_send_h2c_term_req_complete(void *cb_arg)
+{
+	struct nvme_tcp_qpair *tqpair = cb_arg;
+
+	tqpair->state = NVME_TCP_QPAIR_STATE_EXITING;
+}
+
+static void
+nvme_tcp_qpair_send_h2c_term_req(struct nvme_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu,
+				 enum spdk_nvme_tcp_term_req_fes fes, uint32_t error_offset)
+{
+	struct nvme_tcp_pdu *rsp_pdu;
+	struct spdk_nvme_tcp_term_req_hdr *h2c_term_req;
+	uint32_t h2c_term_req_hdr_len = sizeof(*h2c_term_req);
+	uint8_t copy_len;
+
+	rsp_pdu = &tqpair->send_pdu;
+	memset(rsp_pdu, 0, sizeof(*rsp_pdu));
+	h2c_term_req = &rsp_pdu->hdr.term_req;
+	h2c_term_req->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_H2C_TERM_REQ;
+	h2c_term_req->common.hlen = h2c_term_req_hdr_len;
+
+	if ((fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
+	    (fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
+		DSET32(&h2c_term_req->fei, error_offset);
+	}
+
+	copy_len = pdu->hdr.common.hlen;
+	if (copy_len > SPDK_NVME_TCP_TERM_REQ_ERROR_DATA_MAX_SIZE) {
+		copy_len = SPDK_NVME_TCP_TERM_REQ_ERROR_DATA_MAX_SIZE;
+	}
+
+	/* Copy the error info into the buffer */
+	memcpy((uint8_t *)rsp_pdu->hdr.raw + h2c_term_req_hdr_len, pdu->hdr.raw, copy_len);
+	nvme_tcp_pdu_set_data(rsp_pdu, (uint8_t *)rsp_pdu->hdr.raw + h2c_term_req_hdr_len, copy_len);
+
+	/* Contain the header len of the wrong received pdu */
+	h2c_term_req->common.plen = h2c_term_req->common.hlen + copy_len;
+	nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
+	nvme_tcp_qpair_write_pdu(tqpair, rsp_pdu, nvme_tcp_qpair_send_h2c_term_req_complete, NULL);
+
+}
+
+static void
+nvme_tcp_pdu_ch_handle(struct nvme_tcp_qpair *tqpair)
+{
+	struct nvme_tcp_pdu *pdu;
+	uint32_t error_offset = 0;
+	enum spdk_nvme_tcp_term_req_fes fes;
+	uint32_t expected_hlen, hd_len = 0;
+	bool plen_error = false;
+
+	pdu = &tqpair->recv_pdu;
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "pdu type = %d\n", pdu->hdr.common.pdu_type);
+	if (pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_IC_RESP) {
+		if (tqpair->state != NVME_TCP_QPAIR_STATE_INVALID) {
+			SPDK_ERRLOG("Already received IC_RESP PDU, and we should reject this pdu=%p\n", pdu);
+			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
+			goto err;
+		}
+		expected_hlen = sizeof(struct spdk_nvme_tcp_ic_resp);
+		if (pdu->hdr.common.plen != expected_hlen) {
+			plen_error = true;
+		}
+	} else {
+		if (tqpair->state != NVME_TCP_QPAIR_STATE_RUNNING) {
+			SPDK_ERRLOG("The TCP/IP tqpair connection is not negotitated\n");
+			fes = SPDK_NVME_TCP_TERM_REQ_FES_PDU_SEQUENCE_ERROR;
+			goto err;
+		}
+
+		switch (pdu->hdr.common.pdu_type) {
+		case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_RESP:
+			expected_hlen = sizeof(struct spdk_nvme_tcp_rsp);
+			if (pdu->hdr.common.flags & SPDK_NVME_TCP_CH_FLAGS_HDGSTF) {
+				hd_len = SPDK_NVME_TCP_DIGEST_LEN;
+			}
+
+			if (pdu->hdr.common.plen != (expected_hlen + hd_len)) {
+				plen_error = true;
+			}
+			break;
+		case SPDK_NVME_TCP_PDU_TYPE_C2H_DATA:
+			expected_hlen = sizeof(struct spdk_nvme_tcp_c2h_data_hdr);
+			if (pdu->hdr.common.plen < pdu->hdr.common.pdo) {
+				plen_error = true;
+			}
+			break;
+		case SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ:
+			expected_hlen = sizeof(struct spdk_nvme_tcp_term_req_hdr);
+			if ((pdu->hdr.common.plen <= expected_hlen) ||
+			    (pdu->hdr.common.plen > SPDK_NVME_TCP_TERM_REQ_PDU_MAX_SIZE)) {
+				plen_error = true;
+			}
+			break;
+		case SPDK_NVME_TCP_PDU_TYPE_R2T:
+			expected_hlen = sizeof(struct spdk_nvme_tcp_r2t_hdr);
+			if (pdu->hdr.common.flags & SPDK_NVME_TCP_CH_FLAGS_HDGSTF) {
+				hd_len = SPDK_NVME_TCP_DIGEST_LEN;
+			}
+
+			if (pdu->hdr.common.plen != (expected_hlen + hd_len)) {
+				plen_error = true;
+			}
+			break;
+
+		default:
+			SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", tqpair->recv_pdu.hdr.common.pdu_type);
+			fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+			error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, pdu_type);
+			goto err;
+		}
+	}
+
+	if (pdu->hdr.common.hlen != expected_hlen) {
+		SPDK_ERRLOG("Expected PDU header length %u, got %u\n",
+			    expected_hlen, pdu->hdr.common.hlen);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, hlen);
+		goto err;
+
+	} else if (plen_error) {
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_common_pdu_hdr, plen);
+		goto err;
+	} else {
+		nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
+		nvme_tcp_pdu_calc_psh_len(&tqpair->recv_pdu, tqpair->host_hdgst_enable);
+		return;
+	}
+err:
+	nvme_tcp_qpair_send_h2c_term_req(tqpair, pdu, fes, error_offset);
+}
+
+static struct nvme_tcp_req *
+get_nvme_active_req_by_cid(struct nvme_tcp_qpair *tqpair, uint32_t cid)
+{
+	assert(tqpair != NULL);
+	if ((cid >= tqpair->num_entries) || (tqpair->tcp_reqs[cid].state == NVME_TCP_REQ_FREE)) {
+		return NULL;
+	}
+
+	return &tqpair->tcp_reqs[cid];
+}
+
+static void
+nvme_tcp_c2h_data_payload_handle(struct nvme_tcp_qpair *tqpair,
+				 struct nvme_tcp_pdu *pdu, uint32_t *reaped)
+{
+	struct nvme_tcp_req *tcp_req;
+	struct spdk_nvme_tcp_c2h_data_hdr *c2h_data;
+	struct spdk_nvme_cpl cpl = {};
+	uint8_t flags;
+
+	tcp_req = pdu->req;
+	assert(tcp_req != NULL);
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "enter\n");
+	c2h_data = &pdu->hdr.c2h_data;
+	tcp_req->datao += pdu->data_len;
+	flags = c2h_data->common.flags;
+
+	nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
+	if (flags & SPDK_NVME_TCP_C2H_DATA_FLAGS_SUCCESS) {
+		if (tcp_req->datao == tcp_req->req->payload_size) {
+			cpl.status.p = 0;
+		} else {
+			cpl.status.p = 1;
+		}
+
+		cpl.cid = tcp_req->cid;
+		cpl.sqid = tqpair->qpair.id;
+		nvme_tcp_req_complete(tcp_req, &cpl);
+		if (tcp_req->ordering.send_ack) {
+			(*reaped)++;
+		}
+
+		tcp_req->ordering.data_recv = 1;
+		nvme_tcp_req_put_safe(tcp_req);
+	}
+}
+
+static const char *spdk_nvme_tcp_term_req_fes_str[] = {
+	"Invalid PDU Header Field",
+	"PDU Sequence Error",
+	"Header Digest Error",
+	"Data Transfer Out of Range",
+	"Data Transfer Limit Exceeded",
+	"Unsupported parameter",
+};
+
+static void
+nvme_tcp_c2h_term_req_dump(struct spdk_nvme_tcp_term_req_hdr *c2h_term_req)
+{
+	SPDK_ERRLOG("Error info of pdu(%p): %s\n", c2h_term_req,
+		    spdk_nvme_tcp_term_req_fes_str[c2h_term_req->fes]);
+	if ((c2h_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD) ||
+	    (c2h_term_req->fes == SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER)) {
+		SPDK_DEBUGLOG(SPDK_LOG_NVME, "The offset from the start of the PDU header is %u\n",
+			      DGET32(c2h_term_req->fei));
+	}
+	/* we may also need to dump some other info here */
+}
+
+static void
+nvme_tcp_c2h_term_req_payload_handle(struct nvme_tcp_qpair *tqpair,
+				     struct nvme_tcp_pdu *pdu)
+{
+	nvme_tcp_c2h_term_req_dump(&pdu->hdr.term_req);
+	nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
+}
+
+static void
+nvme_tcp_pdu_payload_handle(struct nvme_tcp_qpair *tqpair,
+			    uint32_t *reaped)
+{
+	int rc = 0;
+	struct nvme_tcp_pdu *pdu;
+	uint32_t crc32c, error_offset = 0;
+	enum spdk_nvme_tcp_term_req_fes fes;
+
+	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
+	pdu = &tqpair->recv_pdu;
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "enter\n");
+
+	/* check data digest if need */
+	if (pdu->ddgst_enable) {
+		crc32c = nvme_tcp_pdu_calc_data_digest(pdu);
+		rc = MATCH_DIGEST_WORD(pdu->data_digest, crc32c);
+		if (rc == 0) {
+			SPDK_ERRLOG("data digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
+			fes = SPDK_NVME_TCP_TERM_REQ_FES_HDGST_ERROR;
+			nvme_tcp_qpair_send_h2c_term_req(tqpair, pdu, fes, error_offset);
+			return;
+		}
+	}
+
+	switch (pdu->hdr.common.pdu_type) {
+	case SPDK_NVME_TCP_PDU_TYPE_C2H_DATA:
+		nvme_tcp_c2h_data_payload_handle(tqpair, pdu, reaped);
+		break;
+
+	case SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ:
+		nvme_tcp_c2h_term_req_payload_handle(tqpair, pdu);
+		break;
+
+	default:
+		/* The code should not go to here */
+		SPDK_ERRLOG("The code should not go to here\n");
+		break;
+	}
+}
+
+static void
+nvme_tcp_send_icreq_complete(void *cb_arg)
+{
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "Complete the icreq send for tqpair=%p\n",
+		      (struct nvme_tcp_qpair *)cb_arg);
+}
+
+static void
+nvme_tcp_icresp_handle(struct nvme_tcp_qpair *tqpair,
+		       struct nvme_tcp_pdu *pdu)
+{
+	struct spdk_nvme_tcp_ic_resp *ic_resp = &pdu->hdr.ic_resp;
+	uint32_t error_offset = 0;
+	enum spdk_nvme_tcp_term_req_fes fes;
+	int recv_buf_size;
+
+	/* Only PFV 0 is defined currently */
+	if (ic_resp->pfv != 0) {
+		SPDK_ERRLOG("Expected ICResp PFV %u, got %u\n", 0u, ic_resp->pfv);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_ic_resp, pfv);
+		goto end;
+	}
+
+	if (ic_resp->maxh2cdata < NVME_TCP_PDU_H2C_MIN_DATA_SIZE) {
+		SPDK_ERRLOG("Expected ICResp maxh2cdata >=%u, got %u\n", NVME_TCP_PDU_H2C_MIN_DATA_SIZE,
+			    ic_resp->maxh2cdata);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_ic_resp, maxh2cdata);
+		goto end;
+	}
+	tqpair->maxh2cdata = ic_resp->maxh2cdata;
+
+	if (ic_resp->cpda > SPDK_NVME_TCP_CPDA_MAX) {
+		SPDK_ERRLOG("Expected ICResp cpda <=%u, got %u\n", SPDK_NVME_TCP_CPDA_MAX, ic_resp->cpda);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_ic_resp, cpda);
+		goto end;
+	}
+	tqpair->cpda = ic_resp->cpda;
+
+	tqpair->host_hdgst_enable = ic_resp->dgst.bits.hdgst_enable ? true : false;
+	tqpair->host_ddgst_enable = ic_resp->dgst.bits.ddgst_enable ? true : false;
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "host_hdgst_enable: %u\n", tqpair->host_hdgst_enable);
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "host_ddgst_enable: %u\n", tqpair->host_ddgst_enable);
+
+	/* Now that we know whether digests are enabled, properly size the receive buffer to
+	 * handle several incoming 4K read commands according to SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR
+	 * parameter. */
+	recv_buf_size = 0x1000 + sizeof(struct spdk_nvme_tcp_c2h_data_hdr);
+
+	if (tqpair->host_hdgst_enable) {
+		recv_buf_size += SPDK_NVME_TCP_DIGEST_LEN;
+	}
+
+	if (tqpair->host_ddgst_enable) {
+		recv_buf_size += SPDK_NVME_TCP_DIGEST_LEN;
+	}
+
+	if (spdk_sock_set_recvbuf(tqpair->sock, recv_buf_size * SPDK_NVMF_TCP_RECV_BUF_SIZE_FACTOR) < 0) {
+		SPDK_WARNLOG("Unable to allocate enough memory for receive buffer on tqpair=%p with size=%d\n",
+			     tqpair,
+			     recv_buf_size);
+		/* Not fatal. */
+	}
+
+	tqpair->state = NVME_TCP_QPAIR_STATE_RUNNING;
+	nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
+	return;
+end:
+	nvme_tcp_qpair_send_h2c_term_req(tqpair, pdu, fes, error_offset);
+	return;
+}
+
+static void
+nvme_tcp_capsule_resp_hdr_handle(struct nvme_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu,
+				 uint32_t *reaped)
+{
+	struct nvme_tcp_req *tcp_req;
+	struct spdk_nvme_tcp_rsp *capsule_resp = &pdu->hdr.capsule_resp;
+	uint32_t cid, error_offset = 0;
+	enum spdk_nvme_tcp_term_req_fes fes;
+	struct spdk_nvme_cpl cpl;
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "enter\n");
+	cpl = capsule_resp->rccqe;
+	cid = cpl.cid;
+
+	/* Recv the pdu again */
+	nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
+
+	tcp_req = get_nvme_active_req_by_cid(tqpair, cid);
+	if (!tcp_req) {
+		SPDK_ERRLOG("no tcp_req is found with cid=%u for tqpair=%p\n", cid, tqpair);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_rsp, rccqe);
+		goto end;
+
+	}
+
+	nvme_tcp_req_complete(tcp_req, &cpl);
+	if (tcp_req->ordering.send_ack) {
+		(*reaped)++;
+	}
+
+	tcp_req->ordering.data_recv = 1;
+	nvme_tcp_req_put_safe(tcp_req);
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "complete tcp_req(%p) on tqpair=%p\n", tcp_req, tqpair);
+
+	return;
+
+end:
+	nvme_tcp_qpair_send_h2c_term_req(tqpair, pdu, fes, error_offset);
+	return;
+}
+
+static void
+nvme_tcp_c2h_term_req_hdr_handle(struct nvme_tcp_qpair *tqpair,
+				 struct nvme_tcp_pdu *pdu)
+{
+	struct spdk_nvme_tcp_term_req_hdr *c2h_term_req = &pdu->hdr.term_req;
+	uint32_t error_offset = 0;
+	enum spdk_nvme_tcp_term_req_fes fes;
+
+	if (c2h_term_req->fes > SPDK_NVME_TCP_TERM_REQ_FES_INVALID_DATA_UNSUPPORTED_PARAMETER) {
+		SPDK_ERRLOG("Fatal Error Stauts(FES) is unknown for c2h_term_req pdu=%p\n", pdu);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_term_req_hdr, fes);
+		goto end;
+	}
+
+	/* set the data buffer */
+	nvme_tcp_pdu_set_data(pdu, (uint8_t *)pdu->hdr.raw + c2h_term_req->common.hlen,
+			      c2h_term_req->common.plen - c2h_term_req->common.hlen);
+	nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
+	return;
+end:
+	nvme_tcp_qpair_send_h2c_term_req(tqpair, pdu, fes, error_offset);
+	return;
+}
+
+static void
+nvme_tcp_c2h_data_hdr_handle(struct nvme_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu)
+{
+	struct nvme_tcp_req *tcp_req;
+	struct spdk_nvme_tcp_c2h_data_hdr *c2h_data = &pdu->hdr.c2h_data;
+	uint32_t error_offset = 0;
+	enum spdk_nvme_tcp_term_req_fes fes;
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "enter\n");
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "c2h_data info on tqpair(%p): datao=%u, datal=%u, cccid=%d\n",
+		      tqpair, c2h_data->datao, c2h_data->datal, c2h_data->cccid);
+	tcp_req = get_nvme_active_req_by_cid(tqpair, c2h_data->cccid);
+	if (!tcp_req) {
+		SPDK_ERRLOG("no tcp_req found for c2hdata cid=%d\n", c2h_data->cccid);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_c2h_data_hdr, cccid);
+		goto end;
+
+	}
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "tcp_req(%p) on tqpair(%p): datao=%u, payload_size=%u\n",
+		      tcp_req, tqpair, tcp_req->datao, tcp_req->req->payload_size);
+
+	if (c2h_data->datal > tcp_req->req->payload_size) {
+		SPDK_ERRLOG("Invalid datal for tcp_req(%p), datal(%u) exceeds payload_size(%u)\n",
+			    tcp_req, c2h_data->datal, tcp_req->req->payload_size);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
+		goto end;
+	}
+
+	if (tcp_req->datao != c2h_data->datao) {
+		SPDK_ERRLOG("Invalid datao for tcp_req(%p), received datal(%u) != datao(%u) in tcp_req\n",
+			    tcp_req, c2h_data->datao, tcp_req->datao);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_c2h_data_hdr, datao);
+		goto end;
+	}
+
+	if ((c2h_data->datao + c2h_data->datal) > tcp_req->req->payload_size) {
+		SPDK_ERRLOG("Invalid data range for tcp_req(%p), received (datao(%u) + datal(%u)) > datao(%u) in tcp_req\n",
+			    tcp_req, c2h_data->datao, c2h_data->datal, tcp_req->req->payload_size);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
+		error_offset = offsetof(struct spdk_nvme_tcp_c2h_data_hdr, datal);
+		goto end;
+
+	}
+
+	nvme_tcp_pdu_set_data_buf(pdu, tcp_req->iov, tcp_req->iovcnt,
+				  c2h_data->datao, c2h_data->datal);
+	pdu->req = tcp_req;
+
+	nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD);
+	return;
+
+end:
+	nvme_tcp_qpair_send_h2c_term_req(tqpair, pdu, fes, error_offset);
+	return;
+}
+
+static void
+nvme_tcp_qpair_h2c_data_send_complete(void *cb_arg)
+{
+	struct nvme_tcp_req *tcp_req = cb_arg;
+
+	assert(tcp_req != NULL);
+
+	tcp_req->ordering.send_ack = 1;
+	if (tcp_req->r2tl_remain) {
+		nvme_tcp_send_h2c_data(tcp_req);
+	} else {
+		assert(tcp_req->active_r2ts > 0);
+		tcp_req->active_r2ts--;
+		tcp_req->state = NVME_TCP_REQ_ACTIVE;
+		/* Need also call this function to free the resource */
+		nvme_tcp_req_put_safe(tcp_req);
+	}
+}
+
+static void
+nvme_tcp_send_h2c_data(struct nvme_tcp_req *tcp_req)
+{
+	struct nvme_tcp_qpair *tqpair = nvme_tcp_qpair(tcp_req->req->qpair);
+	struct nvme_tcp_pdu *rsp_pdu;
+	struct spdk_nvme_tcp_h2c_data_hdr *h2c_data;
+	uint32_t plen, pdo, alignment;
+
+	/* Reinit the send_ack and r2t_recv bits */
+	tcp_req->ordering.send_ack = 0;
+	tcp_req->ordering.r2t_recv = 0;
+	rsp_pdu = tcp_req->send_pdu;
+	memset(rsp_pdu, 0, sizeof(*rsp_pdu));
+	h2c_data = &rsp_pdu->hdr.h2c_data;
+
+	h2c_data->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_H2C_DATA;
+	plen = h2c_data->common.hlen = sizeof(*h2c_data);
+	h2c_data->cccid = tcp_req->cid;
+	h2c_data->ttag = tcp_req->ttag;
+	h2c_data->datao = tcp_req->datao;
+
+	h2c_data->datal = spdk_min(tcp_req->r2tl_remain, tqpair->maxh2cdata);
+	nvme_tcp_pdu_set_data_buf(rsp_pdu, tcp_req->iov, tcp_req->iovcnt,
+				  h2c_data->datao, h2c_data->datal);
+	tcp_req->r2tl_remain -= h2c_data->datal;
+
+	if (tqpair->host_hdgst_enable) {
+		h2c_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_HDGSTF;
+		plen += SPDK_NVME_TCP_DIGEST_LEN;
+	}
+
+	rsp_pdu->padding_len = 0;
+	pdo = plen;
+	if (tqpair->cpda) {
+		alignment = (tqpair->cpda + 1) << 2;
+		if (alignment > plen) {
+			rsp_pdu->padding_len = alignment - plen;
+			pdo = plen = alignment;
+		}
+	}
+
+	h2c_data->common.pdo = pdo;
+	plen += h2c_data->datal;
+	if (tqpair->host_ddgst_enable) {
+		h2c_data->common.flags |= SPDK_NVME_TCP_CH_FLAGS_DDGSTF;
+		plen += SPDK_NVME_TCP_DIGEST_LEN;
+	}
+
+	h2c_data->common.plen = plen;
+	tcp_req->datao += h2c_data->datal;
+	if (!tcp_req->r2tl_remain) {
+		h2c_data->common.flags |= SPDK_NVME_TCP_H2C_DATA_FLAGS_LAST_PDU;
+	}
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "h2c_data info: datao=%u, datal=%u, pdu_len=%u for tqpair=%p\n",
+		      h2c_data->datao, h2c_data->datal, h2c_data->common.plen, tqpair);
+
+	nvme_tcp_qpair_write_pdu(tqpair, rsp_pdu, nvme_tcp_qpair_h2c_data_send_complete, tcp_req);
+}
+
+static void
+nvme_tcp_r2t_hdr_handle(struct nvme_tcp_qpair *tqpair, struct nvme_tcp_pdu *pdu)
+{
+	struct nvme_tcp_req *tcp_req;
+	struct spdk_nvme_tcp_r2t_hdr *r2t = &pdu->hdr.r2t;
+	uint32_t cid, error_offset = 0;
+	enum spdk_nvme_tcp_term_req_fes fes;
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "enter\n");
+	cid = r2t->cccid;
+	tcp_req = get_nvme_active_req_by_cid(tqpair, cid);
+	if (!tcp_req) {
+		SPDK_ERRLOG("Cannot find tcp_req for tqpair=%p\n", tqpair);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_r2t_hdr, cccid);
+		goto end;
+	}
+
+	tcp_req->ordering.r2t_recv = 1;
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "r2t info: r2to=%u, r2tl=%u for tqpair=%p\n", r2t->r2to, r2t->r2tl,
+		      tqpair);
+
+	if (tcp_req->state == NVME_TCP_REQ_ACTIVE) {
+		assert(tcp_req->active_r2ts == 0);
+		tcp_req->state = NVME_TCP_REQ_ACTIVE_R2T;
+	}
+
+	tcp_req->active_r2ts++;
+	if (tcp_req->active_r2ts > tqpair->maxr2t) {
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_R2T_LIMIT_EXCEEDED;
+		SPDK_ERRLOG("Invalid R2T: it exceeds the R2T maixmal=%u for tqpair=%p\n", tqpair->maxr2t, tqpair);
+		goto end;
+	}
+
+	if (tcp_req->datao != r2t->r2to) {
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = offsetof(struct spdk_nvme_tcp_r2t_hdr, r2to);
+		goto end;
+
+	}
+
+	if ((r2t->r2tl + r2t->r2to) > tcp_req->req->payload_size) {
+		SPDK_ERRLOG("Invalid R2T info for tcp_req=%p: (r2to(%u) + r2tl(%u)) exceeds payload_size(%u)\n",
+			    tcp_req, r2t->r2to, r2t->r2tl, tqpair->maxh2cdata);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_DATA_TRANSFER_OUT_OF_RANGE;
+		error_offset = offsetof(struct spdk_nvme_tcp_r2t_hdr, r2tl);
+		goto end;
+
+	}
+
+	tcp_req->ttag = r2t->ttag;
+	tcp_req->r2tl_remain = r2t->r2tl;
+	nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
+
+	if (spdk_likely(tcp_req->ordering.send_ack)) {
+		nvme_tcp_send_h2c_data(tcp_req);
+	}
+	return;
+
+end:
+	nvme_tcp_qpair_send_h2c_term_req(tqpair, pdu, fes, error_offset);
+	return;
+
+}
+
+static void
+nvme_tcp_pdu_psh_handle(struct nvme_tcp_qpair *tqpair, uint32_t *reaped)
+{
+	struct nvme_tcp_pdu *pdu;
+	int rc;
+	uint32_t crc32c, error_offset = 0;
+	enum spdk_nvme_tcp_term_req_fes fes;
+
+	assert(tqpair->recv_state == NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH);
+	pdu = &tqpair->recv_pdu;
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "enter: pdu type =%u\n", pdu->hdr.common.pdu_type);
+	/* check header digest if needed */
+	if (pdu->has_hdgst) {
+		crc32c = nvme_tcp_pdu_calc_header_digest(pdu);
+		rc = MATCH_DIGEST_WORD((uint8_t *)pdu->hdr.raw + pdu->hdr.common.hlen, crc32c);
+		if (rc == 0) {
+			SPDK_ERRLOG("header digest error on tqpair=(%p) with pdu=%p\n", tqpair, pdu);
+			fes = SPDK_NVME_TCP_TERM_REQ_FES_HDGST_ERROR;
+			nvme_tcp_qpair_send_h2c_term_req(tqpair, pdu, fes, error_offset);
+			return;
+
+		}
+	}
+
+	switch (pdu->hdr.common.pdu_type) {
+	case SPDK_NVME_TCP_PDU_TYPE_IC_RESP:
+		nvme_tcp_icresp_handle(tqpair, pdu);
+		break;
+	case SPDK_NVME_TCP_PDU_TYPE_CAPSULE_RESP:
+		nvme_tcp_capsule_resp_hdr_handle(tqpair, pdu, reaped);
+		break;
+	case SPDK_NVME_TCP_PDU_TYPE_C2H_DATA:
+		nvme_tcp_c2h_data_hdr_handle(tqpair, pdu);
+		break;
+
+	case SPDK_NVME_TCP_PDU_TYPE_C2H_TERM_REQ:
+		nvme_tcp_c2h_term_req_hdr_handle(tqpair, pdu);
+		break;
+	case SPDK_NVME_TCP_PDU_TYPE_R2T:
+		nvme_tcp_r2t_hdr_handle(tqpair, pdu);
+		break;
+
+	default:
+		SPDK_ERRLOG("Unexpected PDU type 0x%02x\n", tqpair->recv_pdu.hdr.common.pdu_type);
+		fes = SPDK_NVME_TCP_TERM_REQ_FES_INVALID_HEADER_FIELD;
+		error_offset = 1;
+		nvme_tcp_qpair_send_h2c_term_req(tqpair, pdu, fes, error_offset);
+		break;
+	}
+
+}
+
+static int
+nvme_tcp_read_pdu(struct nvme_tcp_qpair *tqpair, uint32_t *reaped)
+{
+	int rc = 0;
+	struct nvme_tcp_pdu *pdu;
+	uint32_t data_len;
+	enum nvme_tcp_pdu_recv_state prev_state;
+
+	/* The loop here is to allow for several back-to-back state changes. */
+	do {
+		prev_state = tqpair->recv_state;
+		switch (tqpair->recv_state) {
+		/* If in a new state */
+		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY:
+			nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH);
+			break;
+		/* common header */
+		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_CH:
+			pdu = &tqpair->recv_pdu;
+			if (pdu->ch_valid_bytes < sizeof(struct spdk_nvme_tcp_common_pdu_hdr)) {
+				rc = nvme_tcp_read_data(tqpair->sock,
+							sizeof(struct spdk_nvme_tcp_common_pdu_hdr) - pdu->ch_valid_bytes,
+							(uint8_t *)&pdu->hdr.common + pdu->ch_valid_bytes);
+				if (rc < 0) {
+					nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
+					break;
+				}
+				pdu->ch_valid_bytes += rc;
+				if (pdu->ch_valid_bytes < sizeof(struct spdk_nvme_tcp_common_pdu_hdr)) {
+					return NVME_TCP_PDU_IN_PROGRESS;
+				}
+			}
+
+			/* The command header of this PDU has now been read from the socket. */
+			nvme_tcp_pdu_ch_handle(tqpair);
+			break;
+		/* Wait for the pdu specific header  */
+		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PSH:
+			pdu = &tqpair->recv_pdu;
+			rc = nvme_tcp_read_data(tqpair->sock,
+						pdu->psh_len - pdu->psh_valid_bytes,
+						(uint8_t *)&pdu->hdr.raw + sizeof(struct spdk_nvme_tcp_common_pdu_hdr) + pdu->psh_valid_bytes);
+			if (rc < 0) {
+				nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
+				break;
+			}
+
+			pdu->psh_valid_bytes += rc;
+			if (pdu->psh_valid_bytes < pdu->psh_len) {
+				return NVME_TCP_PDU_IN_PROGRESS;
+			}
+
+			/* All header(ch, psh, head digist) of this PDU has now been read from the socket. */
+			nvme_tcp_pdu_psh_handle(tqpair, reaped);
+			break;
+		case NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:
+			pdu = &tqpair->recv_pdu;
+			/* check whether the data is valid, if not we just return */
+			if (!pdu->data_len) {
+				return NVME_TCP_PDU_IN_PROGRESS;
+			}
+
+			data_len = pdu->data_len;
+			/* data digest */
+			if (spdk_unlikely((pdu->hdr.common.pdu_type == SPDK_NVME_TCP_PDU_TYPE_C2H_DATA) &&
+					  tqpair->host_ddgst_enable)) {
+				data_len += SPDK_NVME_TCP_DIGEST_LEN;
+				pdu->ddgst_enable = true;
+			}
+
+			rc = nvme_tcp_read_payload_data(tqpair->sock, pdu);
+			if (rc < 0) {
+				nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_ERROR);
+				break;
+			}
+
+			pdu->readv_offset += rc;
+			if (pdu->readv_offset < data_len) {
+				return NVME_TCP_PDU_IN_PROGRESS;
+			}
+
+			assert(pdu->readv_offset == data_len);
+			/* All of this PDU has now been read from the socket. */
+			nvme_tcp_pdu_payload_handle(tqpair, reaped);
+			break;
+		case NVME_TCP_PDU_RECV_STATE_ERROR:
+			rc = NVME_TCP_PDU_FATAL;
+			break;
+		default:
+			assert(0);
+			break;
+		}
+	} while (prev_state != tqpair->recv_state);
+
+	return rc;
+}
+
+static void
+nvme_tcp_qpair_check_timeout(struct spdk_nvme_qpair *qpair)
+{
+	uint64_t t02;
+	struct nvme_tcp_req *tcp_req, *tmp;
+	struct nvme_tcp_qpair *tqpair = nvme_tcp_qpair(qpair);
+	struct spdk_nvme_ctrlr *ctrlr = qpair->ctrlr;
+	struct spdk_nvme_ctrlr_process *active_proc;
+
+	/* Don't check timeouts during controller initialization. */
+	if (ctrlr->state != NVME_CTRLR_STATE_READY) {
+		return;
+	}
+
+	if (nvme_qpair_is_admin_queue(qpair)) {
+		active_proc = nvme_ctrlr_get_current_process(ctrlr);
+	} else {
+		active_proc = qpair->active_proc;
+	}
+
+	/* Only check timeouts if the current process has a timeout callback. */
+	if (active_proc == NULL || active_proc->timeout_cb_fn == NULL) {
+		return;
+	}
+
+	t02 = spdk_get_ticks();
+	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->outstanding_reqs, link, tmp) {
+		assert(tcp_req->req != NULL);
+
+		if (nvme_request_check_timeout(tcp_req->req, tcp_req->cid, active_proc, t02)) {
+			/*
+			 * The requests are in order, so as soon as one has not timed out,
+			 * stop iterating.
+			 */
+			break;
+		}
+	}
+}
+
+static int
+nvme_tcp_qpair_process_completions(struct spdk_nvme_qpair *qpair, uint32_t max_completions)
+{
+	struct nvme_tcp_qpair *tqpair = nvme_tcp_qpair(qpair);
+	uint32_t reaped;
+	int rc;
+
+	rc = spdk_sock_flush(tqpair->sock);
+	if (rc < 0) {
+		return rc;
+	}
+
+	if (max_completions == 0) {
+		max_completions = tqpair->num_entries;
+	} else {
+		max_completions = spdk_min(max_completions, tqpair->num_entries);
+	}
+
+	reaped = 0;
+	do {
+		rc = nvme_tcp_read_pdu(tqpair, &reaped);
+		if (rc < 0) {
+			SPDK_DEBUGLOG(SPDK_LOG_NVME, "Error polling CQ! (%d): %s\n",
+				      errno, spdk_strerror(errno));
+			goto fail;
+		} else if (rc == 0) {
+			/* Partial PDU is read */
+			break;
+		}
+
+	} while (reaped < max_completions);
+
+	if (spdk_unlikely(tqpair->qpair.ctrlr->timeout_enabled)) {
+		nvme_tcp_qpair_check_timeout(qpair);
+	}
+
+	return reaped;
+fail:
+
+	/*
+	 * Since admin queues take the ctrlr_lock before entering this function,
+	 * we can call nvme_transport_ctrlr_disconnect_qpair. For other qpairs we need
+	 * to call the generic function which will take the lock for us.
+	 */
+	qpair->transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_UNKNOWN;
+
+	if (nvme_qpair_is_admin_queue(qpair)) {
+		nvme_transport_ctrlr_disconnect_qpair(qpair->ctrlr, qpair);
+	} else {
+		nvme_ctrlr_disconnect_qpair(qpair);
+	}
+	return -ENXIO;
+}
+
+static void
+nvme_tcp_qpair_sock_cb(void *ctx, struct spdk_sock_group *group, struct spdk_sock *sock)
+{
+	struct spdk_nvme_qpair *qpair = ctx;
+	struct nvme_tcp_poll_group *pgroup = nvme_tcp_poll_group(qpair->poll_group);
+	int32_t num_completions;
+
+	num_completions = spdk_nvme_qpair_process_completions(qpair, pgroup->completions_per_qpair);
+
+	if (pgroup->num_completions >= 0 && num_completions >= 0) {
+		pgroup->num_completions += num_completions;
+	} else {
+		pgroup->num_completions = -ENXIO;
+	}
+}
+
+static int
+nvme_tcp_qpair_icreq_send(struct nvme_tcp_qpair *tqpair)
+{
+	struct spdk_nvme_tcp_ic_req *ic_req;
+	struct nvme_tcp_pdu *pdu;
+	uint64_t icreq_timeout_tsc;
+	int rc;
+
+	pdu = &tqpair->send_pdu;
+	memset(&tqpair->send_pdu, 0, sizeof(tqpair->send_pdu));
+	ic_req = &pdu->hdr.ic_req;
+
+	ic_req->common.pdu_type = SPDK_NVME_TCP_PDU_TYPE_IC_REQ;
+	ic_req->common.hlen = ic_req->common.plen = sizeof(*ic_req);
+	ic_req->pfv = 0;
+	ic_req->maxr2t = NVME_TCP_MAX_R2T_DEFAULT - 1;
+	ic_req->hpda = NVME_TCP_HPDA_DEFAULT;
+
+	ic_req->dgst.bits.hdgst_enable = tqpair->qpair.ctrlr->opts.header_digest;
+	ic_req->dgst.bits.ddgst_enable = tqpair->qpair.ctrlr->opts.data_digest;
+
+	nvme_tcp_qpair_write_pdu(tqpair, pdu, nvme_tcp_send_icreq_complete, tqpair);
+
+	icreq_timeout_tsc = spdk_get_ticks() + (NVME_TCP_TIME_OUT_IN_SECONDS * spdk_get_ticks_hz());
+	do {
+		rc = nvme_tcp_qpair_process_completions(&tqpair->qpair, 0);
+	} while ((tqpair->state == NVME_TCP_QPAIR_STATE_INVALID) &&
+		 (rc == 0) && (spdk_get_ticks() <= icreq_timeout_tsc));
+
+	if (tqpair->state != NVME_TCP_QPAIR_STATE_RUNNING) {
+		SPDK_ERRLOG("Failed to construct the tqpair=%p via correct icresp\n", tqpair);
+		return -1;
+	}
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "Succesfully construct the tqpair=%p via correct icresp\n", tqpair);
+
+	return 0;
+}
+
+static int
+nvme_tcp_ctrlr_connect_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
+{
+	struct sockaddr_storage dst_addr;
+	struct sockaddr_storage src_addr;
+	int rc;
+	struct nvme_tcp_qpair *tqpair;
+	int family;
+	long int port;
+	struct spdk_sock_opts opts;
+
+	tqpair = nvme_tcp_qpair(qpair);
+
+	switch (ctrlr->trid.adrfam) {
+	case SPDK_NVMF_ADRFAM_IPV4:
+		family = AF_INET;
+		break;
+	case SPDK_NVMF_ADRFAM_IPV6:
+		family = AF_INET6;
+		break;
+	default:
+		SPDK_ERRLOG("Unhandled ADRFAM %d\n", ctrlr->trid.adrfam);
+		return -1;
+	}
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "adrfam %d ai_family %d\n", ctrlr->trid.adrfam, family);
+
+	memset(&dst_addr, 0, sizeof(dst_addr));
+
+	SPDK_DEBUGLOG(SPDK_LOG_NVME, "trsvcid is %s\n", ctrlr->trid.trsvcid);
+	rc = nvme_tcp_parse_addr(&dst_addr, family, ctrlr->trid.traddr, ctrlr->trid.trsvcid);
+	if (rc != 0) {
+		SPDK_ERRLOG("dst_addr nvme_tcp_parse_addr() failed\n");
+		return -1;
+	}
+
+	if (ctrlr->opts.src_addr[0] || ctrlr->opts.src_svcid[0]) {
+		memset(&src_addr, 0, sizeof(src_addr));
+		rc = nvme_tcp_parse_addr(&src_addr, family, ctrlr->opts.src_addr, ctrlr->opts.src_svcid);
+		if (rc != 0) {
+			SPDK_ERRLOG("src_addr nvme_tcp_parse_addr() failed\n");
+			return -1;
+		}
+	}
+
+	port = spdk_strtol(ctrlr->trid.trsvcid, 10);
+	if (port <= 0 || port >= INT_MAX) {
+		SPDK_ERRLOG("Invalid port: %s\n", ctrlr->trid.trsvcid);
+		return -1;
+	}
+
+	opts.opts_size = sizeof(opts);
+	spdk_sock_get_default_opts(&opts);
+	opts.priority = ctrlr->trid.priority;
+	tqpair->sock = spdk_sock_connect_ext(ctrlr->trid.traddr, port, NULL, &opts);
+	if (!tqpair->sock) {
+		SPDK_ERRLOG("sock connection error of tqpair=%p with addr=%s, port=%ld\n",
+			    tqpair, ctrlr->trid.traddr, port);
+		return -1;
+	}
+
+	tqpair->maxr2t = NVME_TCP_MAX_R2T_DEFAULT;
+	/* Explicitly set the state and recv_state of tqpair */
+	tqpair->state = NVME_TCP_QPAIR_STATE_INVALID;
+	if (tqpair->recv_state != NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY) {
+		nvme_tcp_qpair_set_recv_state(tqpair, NVME_TCP_PDU_RECV_STATE_AWAIT_PDU_READY);
+	}
+	rc = nvme_tcp_qpair_icreq_send(tqpair);
+	if (rc != 0) {
+		SPDK_ERRLOG("Unable to connect the tqpair\n");
+		return -1;
+	}
+
+	rc = nvme_fabric_qpair_connect(&tqpair->qpair, tqpair->num_entries);
+	if (rc < 0) {
+		SPDK_ERRLOG("Failed to send an NVMe-oF Fabric CONNECT command\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static struct spdk_nvme_qpair *
+nvme_tcp_ctrlr_create_qpair(struct spdk_nvme_ctrlr *ctrlr,
+			    uint16_t qid, uint32_t qsize,
+			    enum spdk_nvme_qprio qprio,
+			    uint32_t num_requests)
+{
+	struct nvme_tcp_qpair *tqpair;
+	struct spdk_nvme_qpair *qpair;
+	int rc;
+
+	tqpair = calloc(1, sizeof(struct nvme_tcp_qpair));
+	if (!tqpair) {
+		SPDK_ERRLOG("failed to get create tqpair\n");
+		return NULL;
+	}
+
+	tqpair->num_entries = qsize;
+	qpair = &tqpair->qpair;
+	rc = nvme_qpair_init(qpair, qid, ctrlr, qprio, num_requests);
+	if (rc != 0) {
+		free(tqpair);
+		return NULL;
+	}
+
+	rc = nvme_tcp_alloc_reqs(tqpair);
+	if (rc) {
+		nvme_tcp_ctrlr_delete_io_qpair(ctrlr, qpair);
+		return NULL;
+	}
+
+	return qpair;
+}
+
+static struct spdk_nvme_qpair *
+nvme_tcp_ctrlr_create_io_qpair(struct spdk_nvme_ctrlr *ctrlr, uint16_t qid,
+			       const struct spdk_nvme_io_qpair_opts *opts)
+{
+	return nvme_tcp_ctrlr_create_qpair(ctrlr, qid, opts->io_queue_size, opts->qprio,
+					   opts->io_queue_requests);
+}
+
+static struct spdk_nvme_ctrlr *nvme_tcp_ctrlr_construct(const struct spdk_nvme_transport_id *trid,
+		const struct spdk_nvme_ctrlr_opts *opts,
+		void *devhandle)
+{
+	struct nvme_tcp_ctrlr *tctrlr;
+	union spdk_nvme_cap_register cap;
+	union spdk_nvme_vs_register vs;
+	int rc;
+
+	tctrlr = calloc(1, sizeof(*tctrlr));
+	if (tctrlr == NULL) {
+		SPDK_ERRLOG("could not allocate ctrlr\n");
+		return NULL;
+	}
+
+	tctrlr->ctrlr.opts = *opts;
+	tctrlr->ctrlr.trid = *trid;
+
+	rc = nvme_ctrlr_construct(&tctrlr->ctrlr);
+	if (rc != 0) {
+		free(tctrlr);
+		return NULL;
+	}
+
+	tctrlr->ctrlr.adminq = nvme_tcp_ctrlr_create_qpair(&tctrlr->ctrlr, 0,
+			       tctrlr->ctrlr.opts.admin_queue_size, 0,
+			       tctrlr->ctrlr.opts.admin_queue_size);
+	if (!tctrlr->ctrlr.adminq) {
+		SPDK_ERRLOG("failed to create admin qpair\n");
+		nvme_tcp_ctrlr_destruct(&tctrlr->ctrlr);
+		return NULL;
+	}
+
+	rc = nvme_transport_ctrlr_connect_qpair(&tctrlr->ctrlr, tctrlr->ctrlr.adminq);
+	if (rc < 0) {
+		SPDK_ERRLOG("failed to connect admin qpair\n");
+		nvme_tcp_ctrlr_destruct(&tctrlr->ctrlr);
+		return NULL;
+	}
+
+	if (nvme_ctrlr_get_cap(&tctrlr->ctrlr, &cap)) {
+		SPDK_ERRLOG("get_cap() failed\n");
+		nvme_ctrlr_destruct(&tctrlr->ctrlr);
+		return NULL;
+	}
+
+	if (nvme_ctrlr_get_vs(&tctrlr->ctrlr, &vs)) {
+		SPDK_ERRLOG("get_vs() failed\n");
+		nvme_ctrlr_destruct(&tctrlr->ctrlr);
+		return NULL;
+	}
+
+	if (nvme_ctrlr_add_process(&tctrlr->ctrlr, 0) != 0) {
+		SPDK_ERRLOG("nvme_ctrlr_add_process() failed\n");
+		nvme_ctrlr_destruct(&tctrlr->ctrlr);
+		return NULL;
+	}
+
+	nvme_ctrlr_init_cap(&tctrlr->ctrlr, &cap, &vs);
+
+	return &tctrlr->ctrlr;
+}
+
+static uint32_t
+nvme_tcp_ctrlr_get_max_xfer_size(struct spdk_nvme_ctrlr *ctrlr)
+{
+	/* TCP transport doens't limit maximum IO transfer size. */
+	return UINT32_MAX;
+}
+
+static uint16_t
+nvme_tcp_ctrlr_get_max_sges(struct spdk_nvme_ctrlr *ctrlr)
+{
+	/*
+	 * We do not support >1 SGE in the initiator currently,
+	 *  so we can only return 1 here.  Once that support is
+	 *  added, this should return ctrlr->cdata.nvmf_specific.msdbd
+	 *  instead.
+	 */
+	return 1;
+}
+
+static int
+nvme_tcp_qpair_iterate_requests(struct spdk_nvme_qpair *qpair,
+				int (*iter_fn)(struct nvme_request *req, void *arg),
+				void *arg)
+{
+	struct nvme_tcp_qpair *tqpair = nvme_tcp_qpair(qpair);
+	struct nvme_tcp_req *tcp_req, *tmp;
+	int rc;
+
+	assert(iter_fn != NULL);
+
+	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->outstanding_reqs, link, tmp) {
+		assert(tcp_req->req != NULL);
+
+		rc = iter_fn(tcp_req->req, arg);
+		if (rc != 0) {
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
+static void
+nvme_tcp_admin_qpair_abort_aers(struct spdk_nvme_qpair *qpair)
+{
+	struct nvme_tcp_req *tcp_req, *tmp;
+	struct spdk_nvme_cpl cpl;
+	struct nvme_tcp_qpair *tqpair = nvme_tcp_qpair(qpair);
+
+	cpl.status.sc = SPDK_NVME_SC_ABORTED_SQ_DELETION;
+	cpl.status.sct = SPDK_NVME_SCT_GENERIC;
+
+	TAILQ_FOREACH_SAFE(tcp_req, &tqpair->outstanding_reqs, link, tmp) {
+		assert(tcp_req->req != NULL);
+		if (tcp_req->req->cmd.opc != SPDK_NVME_OPC_ASYNC_EVENT_REQUEST) {
+			continue;
+		}
+
+		nvme_tcp_req_complete(tcp_req, &cpl);
+		nvme_tcp_req_put(tqpair, tcp_req);
+	}
+}
+
+static struct spdk_nvme_transport_poll_group *
+nvme_tcp_poll_group_create(void)
+{
+	struct nvme_tcp_poll_group *group = calloc(1, sizeof(*group));
+
+	if (group == NULL) {
+		SPDK_ERRLOG("Unable to allocate poll group.\n");
+		return NULL;
+	}
+
+	group->sock_group = spdk_sock_group_create(group);
+	if (group->sock_group == NULL) {
+		free(group);
+		SPDK_ERRLOG("Unable to allocate sock group.\n");
+		return NULL;
+	}
+
+	return &group->group;
+}
+
+static int
+nvme_tcp_poll_group_connect_qpair(struct spdk_nvme_qpair *qpair)
+{
+	struct nvme_tcp_poll_group *group = nvme_tcp_poll_group(qpair->poll_group);
+	struct nvme_tcp_qpair *tqpair = nvme_tcp_qpair(qpair);
+
+	if (spdk_sock_group_add_sock(group->sock_group, tqpair->sock, nvme_tcp_qpair_sock_cb, qpair)) {
+		return -EPROTO;
+	}
+	return 0;
+}
+
+static int
+nvme_tcp_poll_group_disconnect_qpair(struct spdk_nvme_qpair *qpair)
+{
+	struct nvme_tcp_poll_group *group = nvme_tcp_poll_group(qpair->poll_group);
+	struct nvme_tcp_qpair *tqpair = nvme_tcp_qpair(qpair);
+
+	if (tqpair->sock && group->sock_group) {
+		if (spdk_sock_group_remove_sock(group->sock_group, tqpair->sock)) {
+			return -EPROTO;
+		}
+	}
+	return 0;
+}
+
+static int
+nvme_tcp_poll_group_add(struct spdk_nvme_transport_poll_group *tgroup,
+			struct spdk_nvme_qpair *qpair)
+{
+	struct nvme_tcp_qpair *tqpair = nvme_tcp_qpair(qpair);
+	struct nvme_tcp_poll_group *group = nvme_tcp_poll_group(tgroup);
+
+	/* disconnected qpairs won't have a sock to add. */
+	if (nvme_qpair_get_state(qpair) >= NVME_QPAIR_CONNECTED) {
+		if (spdk_sock_group_add_sock(group->sock_group, tqpair->sock, nvme_tcp_qpair_sock_cb, qpair)) {
+			return -EPROTO;
+		}
+	}
+
+	return 0;
+}
+
+static int
+nvme_tcp_poll_group_remove(struct spdk_nvme_transport_poll_group *tgroup,
+			   struct spdk_nvme_qpair *qpair)
+{
+	if (qpair->poll_group_tailq_head == &tgroup->connected_qpairs) {
+		return nvme_poll_group_disconnect_qpair(qpair);
+	}
+
+	return 0;
+}
+
+static int64_t
+nvme_tcp_poll_group_process_completions(struct spdk_nvme_transport_poll_group *tgroup,
+					uint32_t completions_per_qpair, spdk_nvme_disconnected_qpair_cb disconnected_qpair_cb)
+{
+	struct nvme_tcp_poll_group *group = nvme_tcp_poll_group(tgroup);
+	struct spdk_nvme_qpair *qpair, *tmp_qpair;
+
+	group->completions_per_qpair = completions_per_qpair;
+	group->num_completions = 0;
+
+	spdk_sock_group_poll(group->sock_group);
+
+	STAILQ_FOREACH_SAFE(qpair, &tgroup->disconnected_qpairs, poll_group_stailq, tmp_qpair) {
+		disconnected_qpair_cb(qpair, tgroup->group->ctx);
+	}
+
+	return group->num_completions;
+}
+
+static int
+nvme_tcp_poll_group_destroy(struct spdk_nvme_transport_poll_group *tgroup)
+{
+	int rc;
+	struct nvme_tcp_poll_group *group = nvme_tcp_poll_group(tgroup);
+
+	if (!STAILQ_EMPTY(&tgroup->connected_qpairs) || !STAILQ_EMPTY(&tgroup->disconnected_qpairs)) {
+		return -EBUSY;
+	}
+
+	rc = spdk_sock_group_close(&group->sock_group);
+	if (rc != 0) {
+		SPDK_ERRLOG("Failed to close the sock group for a tcp poll group.\n");
+		assert(false);
+	}
+
+	free(tgroup);
+
+	return 0;
+}
+
+const struct spdk_nvme_transport_ops tcp_ops = {
+	.name = "TCP",
+	.type = SPDK_NVME_TRANSPORT_TCP,
+	.ctrlr_construct = nvme_tcp_ctrlr_construct,
+	.ctrlr_scan = nvme_fabric_ctrlr_scan,
+	.ctrlr_destruct = nvme_tcp_ctrlr_destruct,
+	.ctrlr_enable = nvme_tcp_ctrlr_enable,
+
+	.ctrlr_set_reg_4 = nvme_fabric_ctrlr_set_reg_4,
+	.ctrlr_set_reg_8 = nvme_fabric_ctrlr_set_reg_8,
+	.ctrlr_get_reg_4 = nvme_fabric_ctrlr_get_reg_4,
+	.ctrlr_get_reg_8 = nvme_fabric_ctrlr_get_reg_8,
+
+	.ctrlr_get_max_xfer_size = nvme_tcp_ctrlr_get_max_xfer_size,
+	.ctrlr_get_max_sges = nvme_tcp_ctrlr_get_max_sges,
+
+	.ctrlr_create_io_qpair = nvme_tcp_ctrlr_create_io_qpair,
+	.ctrlr_delete_io_qpair = nvme_tcp_ctrlr_delete_io_qpair,
+	.ctrlr_connect_qpair = nvme_tcp_ctrlr_connect_qpair,
+	.ctrlr_disconnect_qpair = nvme_tcp_ctrlr_disconnect_qpair,
+
+	.qpair_abort_reqs = nvme_tcp_qpair_abort_reqs,
+	.qpair_reset = nvme_tcp_qpair_reset,
+	.qpair_submit_request = nvme_tcp_qpair_submit_request,
+	.qpair_process_completions = nvme_tcp_qpair_process_completions,
+	.qpair_iterate_requests = nvme_tcp_qpair_iterate_requests,
+	.admin_qpair_abort_aers = nvme_tcp_admin_qpair_abort_aers,
+
+	.poll_group_create = nvme_tcp_poll_group_create,
+	.poll_group_connect_qpair = nvme_tcp_poll_group_connect_qpair,
+	.poll_group_disconnect_qpair = nvme_tcp_poll_group_disconnect_qpair,
+	.poll_group_add = nvme_tcp_poll_group_add,
+	.poll_group_remove = nvme_tcp_poll_group_remove,
+	.poll_group_process_completions = nvme_tcp_poll_group_process_completions,
+	.poll_group_destroy = nvme_tcp_poll_group_destroy,
+};
+
+SPDK_NVME_TRANSPORT_REGISTER(tcp, &tcp_ops);