diff --git a/include/spdk_internal/nvme_tcp.h b/include/spdk_internal/nvme_tcp.h
index 3345880c1b..01f0ad8a1c 100644
--- a/include/spdk_internal/nvme_tcp.h
+++ b/include/spdk_internal/nvme_tcp.h
@@ -38,6 +38,8 @@
 #include "spdk/sock.h"
 #include "spdk/dif.h"
 
+#include "sgl.h"
+
 #define SPDK_CRC32C_XOR				0xffffffffUL
 #define SPDK_NVME_TCP_DIGEST_LEN		4
 #define SPDK_NVME_TCP_DIGEST_ALIGNMENT		4
@@ -76,13 +78,6 @@
 
 typedef void (*nvme_tcp_qpair_xfer_complete_cb)(void *cb_arg);
 
-struct _nvme_tcp_sgl {
-	struct iovec	*iov;
-	int		iovcnt;
-	uint32_t	iov_offset;
-	uint32_t	total_size;
-};
-
 struct nvme_tcp_pdu {
 	union {
 		/* to hold error pdu data */
@@ -125,7 +120,7 @@ struct nvme_tcp_pdu {
 	TAILQ_ENTRY(nvme_tcp_pdu)			tailq;
 	uint32_t					remaining;
 	uint32_t					padding_len;
-	struct _nvme_tcp_sgl				sgl;
+	struct spdk_iov_sgl				sgl;
 
 	struct spdk_dif_ctx				*dif_ctx;
 
@@ -248,32 +243,7 @@ nvme_tcp_pdu_calc_data_digest(struct nvme_tcp_pdu *pdu)
 }
 
 static inline void
-_nvme_tcp_sgl_init(struct _nvme_tcp_sgl *s, struct iovec *iov, int iovcnt,
-		   uint32_t iov_offset)
-{
-	s->iov = iov;
-	s->iovcnt = iovcnt;
-	s->iov_offset = iov_offset;
-	s->total_size = 0;
-}
-
-static inline void
-_nvme_tcp_sgl_advance(struct _nvme_tcp_sgl *s, uint32_t step)
-{
-	s->iov_offset += step;
-	while (s->iovcnt > 0) {
-		if (s->iov_offset < s->iov->iov_len) {
-			break;
-		}
-
-		s->iov_offset -= s->iov->iov_len;
-		s->iov++;
-		s->iovcnt--;
-	}
-}
-
-static inline void
-_nvme_tcp_sgl_get_buf(struct _nvme_tcp_sgl *s, void **_buf, uint32_t *_buf_len)
+_nvme_tcp_sgl_get_buf(struct spdk_iov_sgl *s, void **_buf, uint32_t *_buf_len)
 {
 	if (_buf != NULL) {
 		*_buf = s->iov->iov_base + s->iov_offset;
@@ -284,33 +254,12 @@ _nvme_tcp_sgl_get_buf(struct _nvme_tcp_sgl *s, void **_buf, uint32_t *_buf_len)
 }
 
 static inline bool
-_nvme_tcp_sgl_append(struct _nvme_tcp_sgl *s, uint8_t *data, uint32_t data_len)
-{
-	if (s->iov_offset >= data_len) {
-		s->iov_offset -= data_len;
-	} else {
-		assert(s->iovcnt > 0);
-		s->iov->iov_base = data + s->iov_offset;
-		s->iov->iov_len = data_len - s->iov_offset;
-		s->total_size += data_len - s->iov_offset;
-		s->iov_offset = 0;
-		s->iov++;
-		s->iovcnt--;
-		if (s->iovcnt == 0) {
-			return false;
-		}
-	}
-
-	return true;
-}
-
-static inline bool
-_nvme_tcp_sgl_append_multi(struct _nvme_tcp_sgl *s, struct iovec *iov, int iovcnt)
+_nvme_tcp_sgl_append_multi(struct spdk_iov_sgl *s, struct iovec *iov, int iovcnt)
 {
 	int i;
 
 	for (i = 0; i < iovcnt; i++) {
-		if (!_nvme_tcp_sgl_append(s, iov[i].iov_base, iov[i].iov_len)) {
+		if (!spdk_iov_sgl_append(s, iov[i].iov_base, iov[i].iov_len)) {
 			return false;
 		}
 	}
@@ -332,7 +281,7 @@ _get_iov_array_size(struct iovec *iov, int iovcnt)
 }
 
 static inline bool
-_nvme_tcp_sgl_append_multi_with_md(struct _nvme_tcp_sgl *s, struct iovec *iov, int iovcnt,
+_nvme_tcp_sgl_append_multi_with_md(struct spdk_iov_sgl *s, struct iovec *iov, int iovcnt,
 				   uint32_t data_len, const struct spdk_dif_ctx *dif_ctx)
 {
 	int rc;
@@ -368,14 +317,14 @@ nvme_tcp_build_iovs(struct iovec *iov, int iovcnt, struct nvme_tcp_pdu *pdu,
 		    bool hdgst_enable, bool ddgst_enable, uint32_t *_mapped_length)
 {
 	uint32_t hlen, plen;
-	struct _nvme_tcp_sgl *sgl;
+	struct spdk_iov_sgl *sgl;
 
 	if (iovcnt == 0) {
 		return 0;
 	}
 
 	sgl = &pdu->sgl;
-	_nvme_tcp_sgl_init(sgl, iov, iovcnt, 0);
+	spdk_iov_sgl_init(sgl, iov, iovcnt, 0);
 	hlen = pdu->hdr.common.hlen;
 
 	/* Header Digest */
@@ -386,7 +335,7 @@ nvme_tcp_build_iovs(struct iovec *iov, int iovcnt, struct nvme_tcp_pdu *pdu,
 	plen = hlen;
 	if (!pdu->data_len) {
 		/* PDU header + possible header digest */
-		_nvme_tcp_sgl_append(sgl, (uint8_t *)&pdu->hdr.raw, hlen);
+		spdk_iov_sgl_append(sgl, (uint8_t *)&pdu->hdr.raw, hlen);
 		goto end;
 	}
 
@@ -396,7 +345,7 @@ nvme_tcp_build_iovs(struct iovec *iov, int iovcnt, struct nvme_tcp_pdu *pdu,
 		plen = hlen;
 	}
 
-	if (!_nvme_tcp_sgl_append(sgl, (uint8_t *)&pdu->hdr.raw, hlen)) {
+	if (!spdk_iov_sgl_append(sgl, (uint8_t *)&pdu->hdr.raw, hlen)) {
 		goto end;
 	}
 
@@ -416,7 +365,7 @@ nvme_tcp_build_iovs(struct iovec *iov, int iovcnt, struct nvme_tcp_pdu *pdu,
 	/* Data Digest */
 	if (g_nvme_tcp_ddgst[pdu->hdr.common.pdu_type] && ddgst_enable) {
 		plen += SPDK_NVME_TCP_DIGEST_LEN;
-		_nvme_tcp_sgl_append(sgl, pdu->data_digest, SPDK_NVME_TCP_DIGEST_LEN);
+		spdk_iov_sgl_append(sgl, pdu->data_digest, SPDK_NVME_TCP_DIGEST_LEN);
 	}
 
 	assert(plen == pdu->hdr.common.plen);
@@ -433,14 +382,14 @@ static int
 nvme_tcp_build_payload_iovs(struct iovec *iov, int iovcnt, struct nvme_tcp_pdu *pdu,
 			    bool ddgst_enable, uint32_t *_mapped_length)
 {
-	struct _nvme_tcp_sgl *sgl;
+	struct spdk_iov_sgl *sgl;
 
 	if (iovcnt == 0) {
 		return 0;
 	}
 
 	sgl = &pdu->sgl;
-	_nvme_tcp_sgl_init(sgl, iov, iovcnt, pdu->rw_offset);
+	spdk_iov_sgl_init(sgl, iov, iovcnt, pdu->rw_offset);
 
 	if (spdk_likely(!pdu->dif_ctx)) {
 		if (!_nvme_tcp_sgl_append_multi(sgl, pdu->data_iov, pdu->data_iovcnt)) {
@@ -455,7 +404,7 @@ nvme_tcp_build_payload_iovs(struct iovec *iov, int iovcnt, struct nvme_tcp_pdu *
 
 	/* Data Digest */
 	if (ddgst_enable) {
-		_nvme_tcp_sgl_append(sgl, pdu->data_digest, SPDK_NVME_TCP_DIGEST_LEN);
+		spdk_iov_sgl_append(sgl, pdu->data_digest, SPDK_NVME_TCP_DIGEST_LEN);
 	}
 
 end:
@@ -565,7 +514,7 @@ nvme_tcp_pdu_set_data_buf(struct nvme_tcp_pdu *pdu,
 {
 	uint32_t buf_offset, buf_len, remain_len, len;
 	uint8_t *buf;
-	struct _nvme_tcp_sgl *pdu_sgl, buf_sgl;
+	struct spdk_iov_sgl *pdu_sgl, buf_sgl;
 
 	pdu->data_len = data_len;
 
@@ -583,20 +532,20 @@ nvme_tcp_pdu_set_data_buf(struct nvme_tcp_pdu *pdu,
 	} else {
 		pdu_sgl = &pdu->sgl;
 
-		_nvme_tcp_sgl_init(pdu_sgl, pdu->data_iov, NVME_TCP_MAX_SGL_DESCRIPTORS, 0);
-		_nvme_tcp_sgl_init(&buf_sgl, iov, iovcnt, 0);
+		spdk_iov_sgl_init(pdu_sgl, pdu->data_iov, NVME_TCP_MAX_SGL_DESCRIPTORS, 0);
+		spdk_iov_sgl_init(&buf_sgl, iov, iovcnt, 0);
 
-		_nvme_tcp_sgl_advance(&buf_sgl, buf_offset);
+		spdk_iov_sgl_advance(&buf_sgl, buf_offset);
 		remain_len = buf_len;
 
 		while (remain_len > 0) {
 			_nvme_tcp_sgl_get_buf(&buf_sgl, (void *)&buf, &len);
 			len = spdk_min(len, remain_len);
 
-			_nvme_tcp_sgl_advance(&buf_sgl, len);
+			spdk_iov_sgl_advance(&buf_sgl, len);
 			remain_len -= len;
 
-			if (!_nvme_tcp_sgl_append(pdu_sgl, buf, len)) {
+			if (!spdk_iov_sgl_append(pdu_sgl, buf, len)) {
 				break;
 			}
 		}
diff --git a/include/spdk_internal/sgl.h b/include/spdk_internal/sgl.h
new file mode 100644
index 0000000000..9fee65d425
--- /dev/null
+++ b/include/spdk_internal/sgl.h
@@ -0,0 +1,127 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright (c) Intel Corporation.
+ *   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.
+ */
+
+#ifndef __SGL_INTERNAL_H__
+#define __SGL_INTERNAL_H__
+
+#include "spdk/stdinc.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct spdk_iov_sgl {
+	struct iovec    *iov;
+	int             iovcnt;
+	uint32_t        iov_offset;
+	uint32_t        total_size;
+};
+
+/**
+ * Initialize struct spdk_iov_sgl with iov, iovcnt and iov_offset.
+ *
+ * \param s the spdk_iov_sgl to be filled.
+ * \param iov the io vector to fill the s
+ * \param iovcnt the size the iov
+ * \param iov_offset the current filled iov_offset for s.
+ */
+
+static inline void
+spdk_iov_sgl_init(struct spdk_iov_sgl *s, struct iovec *iov, int iovcnt,
+		  uint32_t iov_offset)
+{
+	s->iov = iov;
+	s->iovcnt = iovcnt;
+	s->iov_offset = iov_offset;
+	s->total_size = 0;
+}
+
+/**
+ * Consume the iovs in spdk_iov_sgl with passed bytes
+ *
+ * \param s the spdk_iov_sgl which contains the iov
+ * \param step the bytes_size consumed.
+ */
+
+static inline void
+spdk_iov_sgl_advance(struct spdk_iov_sgl *s, uint32_t step)
+{
+	s->iov_offset += step;
+	while (s->iovcnt > 0) {
+		assert(s->iov != NULL);
+		if (s->iov_offset < s->iov->iov_len) {
+			break;
+		}
+
+		s->iov_offset -= s->iov->iov_len;
+		s->iov++;
+		s->iovcnt--;
+	}
+}
+
+/**
+ * Append the data to the struct spdk_iov_sgl pointed by s
+ *
+ * \param s the address of the struct spdk_iov_sgl
+ * \param data the data buffer to be appended
+ * \param data_len the length of the data.
+ *
+ * \return true if all the data is appended.
+ */
+
+static inline bool
+spdk_iov_sgl_append(struct spdk_iov_sgl *s, uint8_t *data, uint32_t data_len)
+{
+	if (s->iov_offset >= data_len) {
+		s->iov_offset -= data_len;
+	} else {
+		assert(s->iovcnt > 0);
+		s->iov->iov_base = data + s->iov_offset;
+		s->iov->iov_len = data_len - s->iov_offset;
+		s->total_size += data_len - s->iov_offset;
+		s->iov_offset = 0;
+		s->iov++;
+		s->iovcnt--;
+		if (s->iovcnt == 0) {
+			return false;
+		}
+	}
+
+	return true;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __SGL_INTERNAL_H__ */
diff --git a/lib/iscsi/iscsi.c b/lib/iscsi/iscsi.c
index dcd2aa3954..842e167d7b 100644
--- a/lib/iscsi/iscsi.c
+++ b/lib/iscsi/iscsi.c
@@ -57,6 +57,8 @@
 
 #include "spdk/log.h"
 
+#include "spdk_internal/sgl.h"
+
 #define MAX_TMPBUF 1024
 
 #ifdef __FreeBSD__
@@ -387,49 +389,11 @@ iscsi_conn_read_data_segment(struct spdk_iscsi_conn *conn,
 	}
 }
 
-struct _iscsi_sgl {
-	struct iovec	*iov;
-	int		iovcnt;
-	uint32_t	iov_offset;
-	uint32_t	total_size;
-};
-
-static inline void
-_iscsi_sgl_init(struct _iscsi_sgl *s, struct iovec *iovs, int iovcnt,
-		uint32_t iov_offset)
-{
-	s->iov = iovs;
-	s->iovcnt = iovcnt;
-	s->iov_offset = iov_offset;
-	s->total_size = 0;
-}
-
-static inline bool
-_iscsi_sgl_append(struct _iscsi_sgl *s, uint8_t *data, uint32_t data_len)
-{
-	if (s->iov_offset >= data_len) {
-		s->iov_offset -= data_len;
-	} else {
-		assert(s->iovcnt > 0);
-		s->iov->iov_base = data + s->iov_offset;
-		s->iov->iov_len = data_len - s->iov_offset;
-		s->total_size += data_len - s->iov_offset;
-		s->iov_offset = 0;
-		s->iov++;
-		s->iovcnt--;
-		if (s->iovcnt == 0) {
-			return false;
-		}
-	}
-
-	return true;
-}
-
 /* Build iovec array to leave metadata space for every data block
  * when reading data segment from socket.
  */
 static inline bool
-_iscsi_sgl_append_with_md(struct _iscsi_sgl *s,
+_iscsi_sgl_append_with_md(struct spdk_iov_sgl *s,
 			  void *buf, uint32_t buf_len, uint32_t data_len,
 			  struct spdk_dif_ctx *dif_ctx)
 {
@@ -468,7 +432,7 @@ int
 iscsi_build_iovs(struct spdk_iscsi_conn *conn, struct iovec *iovs, int iovcnt,
 		 struct spdk_iscsi_pdu *pdu, uint32_t *_mapped_length)
 {
-	struct _iscsi_sgl sgl;
+	struct spdk_iov_sgl sgl;
 	int enable_digest;
 	uint32_t total_ahs_len;
 	uint32_t data_len;
@@ -487,22 +451,22 @@ iscsi_build_iovs(struct spdk_iscsi_conn *conn, struct iovec *iovs, int iovcnt,
 		enable_digest = 0;
 	}
 
-	_iscsi_sgl_init(&sgl, iovs, iovcnt, pdu->writev_offset);
+	spdk_iov_sgl_init(&sgl, iovs, iovcnt, pdu->writev_offset);
 
 	/* BHS */
-	if (!_iscsi_sgl_append(&sgl, (uint8_t *)&pdu->bhs, ISCSI_BHS_LEN)) {
+	if (!spdk_iov_sgl_append(&sgl, (uint8_t *)&pdu->bhs, ISCSI_BHS_LEN)) {
 		goto end;
 	}
 	/* AHS */
 	if (total_ahs_len > 0) {
-		if (!_iscsi_sgl_append(&sgl, pdu->ahs, 4 * total_ahs_len)) {
+		if (!spdk_iov_sgl_append(&sgl, pdu->ahs, 4 * total_ahs_len)) {
 			goto end;
 		}
 	}
 
 	/* Header Digest */
 	if (enable_digest && conn->header_digest) {
-		if (!_iscsi_sgl_append(&sgl, pdu->header_digest, ISCSI_DIGEST_LEN)) {
+		if (!spdk_iov_sgl_append(&sgl, pdu->header_digest, ISCSI_DIGEST_LEN)) {
 			goto end;
 		}
 	}
@@ -510,7 +474,7 @@ iscsi_build_iovs(struct spdk_iscsi_conn *conn, struct iovec *iovs, int iovcnt,
 	/* Data Segment */
 	if (data_len > 0) {
 		if (!pdu->dif_insert_or_strip) {
-			if (!_iscsi_sgl_append(&sgl, pdu->data, data_len)) {
+			if (!spdk_iov_sgl_append(&sgl, pdu->data, data_len)) {
 				goto end;
 			}
 		} else {
@@ -523,7 +487,7 @@ iscsi_build_iovs(struct spdk_iscsi_conn *conn, struct iovec *iovs, int iovcnt,
 
 	/* Data Digest */
 	if (enable_digest && conn->data_digest && data_len != 0) {
-		_iscsi_sgl_append(&sgl, pdu->data_digest, ISCSI_DIGEST_LEN);
+		spdk_iov_sgl_append(&sgl, pdu->data_digest, ISCSI_DIGEST_LEN);
 	}
 
 end: