From 6358538aa708bde183f0dcff0c9dc55bb7babda1 Mon Sep 17 00:00:00 2001
From: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Date: Mon, 15 Feb 2021 03:25:38 +0900
Subject: [PATCH] lib/iscsi: Pass the range (offset and length) to
 iscsi_conn_read_data_segment()

This will make the current code simpler and make the following changes easier.

Signed-off-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: I5a06f7e876fee03ed05d880525b594f92cadcdca
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/6410
Reviewed-by: Ziye Yang <ziye.yang@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot
---
 lib/iscsi/iscsi.c                     | 17 ++++++++---------
 test/app/fuzz/iscsi_fuzz/iscsi_fuzz.c |  4 +++-
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/lib/iscsi/iscsi.c b/lib/iscsi/iscsi.c
index 2f5967801..3a8c0a352 100644
--- a/lib/iscsi/iscsi.c
+++ b/lib/iscsi/iscsi.c
@@ -348,27 +348,23 @@ iscsi_pdu_calc_data_digest(struct spdk_iscsi_pdu *pdu)
 static int
 iscsi_conn_read_data_segment(struct spdk_iscsi_conn *conn,
 			     struct spdk_iscsi_pdu *pdu,
-			     uint32_t segment_len)
+			     uint32_t data_offset, uint32_t data_len)
 {
 	struct iovec buf_iov, iovs[32];
 	int rc, _rc;
 
 	if (spdk_likely(!pdu->dif_insert_or_strip)) {
-		return iscsi_conn_read_data(conn,
-					    segment_len - pdu->data_valid_bytes,
-					    pdu->data + pdu->data_valid_bytes);
+		return iscsi_conn_read_data(conn, data_len, pdu->data + data_offset);
 	} else {
 		buf_iov.iov_base = pdu->data;
 		buf_iov.iov_len = pdu->data_buf_len;
 		rc = spdk_dif_set_md_interleave_iovs(iovs, 32, &buf_iov, 1,
-						     pdu->data_valid_bytes,
-						     segment_len - pdu->data_valid_bytes, NULL,
+						     data_offset, data_len, NULL,
 						     &pdu->dif_ctx);
 		if (rc > 0) {
 			rc = iscsi_conn_readv_data(conn, iovs, rc);
 			if (rc > 0) {
-				_rc = spdk_dif_generate_stream(&buf_iov, 1,
-							       pdu->data_valid_bytes, rc,
+				_rc = spdk_dif_generate_stream(&buf_iov, 1, data_offset, rc,
 							       &pdu->dif_ctx);
 				if (_rc != 0) {
 					SPDK_ERRLOG("DIF generate failed\n");
@@ -4590,7 +4586,10 @@ iscsi_pdu_payload_read(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu)
 
 	/* copy the actual data into local buffer */
 	if ((pdu->data_valid_bytes < data_len)) {
-		rc = iscsi_conn_read_data_segment(conn, pdu, data_len);
+		rc = iscsi_conn_read_data_segment(conn,
+						  pdu,
+						  pdu->data_valid_bytes,
+						  data_len - pdu->data_valid_bytes);
 		if (rc < 0) {
 			return rc;
 		}
diff --git a/test/app/fuzz/iscsi_fuzz/iscsi_fuzz.c b/test/app/fuzz/iscsi_fuzz/iscsi_fuzz.c
index a7dc2fee2..8261ae82d 100644
--- a/test/app/fuzz/iscsi_fuzz/iscsi_fuzz.c
+++ b/test/app/fuzz/iscsi_fuzz/iscsi_fuzz.c
@@ -488,7 +488,9 @@ iscsi_fuzz_read_pdu(struct spdk_iscsi_conn *conn)
 
 			/* copy the actual data into local buffer */
 			if (pdu->data_valid_bytes < data_len) {
-				rc = iscsi_conn_read_data_segment(conn, pdu, data_len);
+				rc = iscsi_conn_read_data_segment(conn, pdu,
+								  pdu->data_valid_bytes,
+								  data_len - pdu->data_valid_bytes);
 				if (rc < 0) {
 					conn->pdu_recv_state = ISCSI_PDU_RECV_STATE_ERROR;
 					break;