[stgt] [PATCH 1/2] Fix buffer_offset set to 0 in the last Data-IN carrying status

[nezhinsky at gmail.com]

From: Alexander Nezhinsky <nezhinsky at gmail.com>

The same function was called both for setting residual counts
in data_in with status and scsi_response pdus. Bi-directional
status, being set to 0 for scsi_response when data_in is actually
passed, resets buffer_offset field inadvertently.

This precluded formatting LUNs exported thru iSCSI to a Windows
initiator.

The fix is to separate these cases and to call a specialized
function for reseidual count carried in data_in with status.
---
 usr/iscsi/iscsid.c |   18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/usr/iscsi/iscsid.c b/usr/iscsi/iscsid.c
index b10be1d..e1180fb 100644
--- a/usr/iscsi/iscsid.c
+++ b/usr/iscsi/iscsid.c
@@ -1012,6 +1012,21 @@ static void cmnd_finish(struct iscsi_connection *conn)
 	}
 }
 
+void iscsi_set_data_rsp_residual(struct iscsi_data_rsp *data_in, struct scsi_cmd *scmd)
+{
+	int32_t resid = scsi_get_in_resid(scmd);
+
+	if (likely(!resid))
+		data_in->residual_count = 0;
+	else if (resid > 0) {
+		data_in->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
+		data_in->residual_count = cpu_to_be32((uint32_t)resid);
+	} else {
+		data_in->flags |= ISCSI_FLAG_CMD_OVERFLOW;
+		data_in->residual_count = cpu_to_be32((uint32_t)-resid);
+	}
+}
+
 static inline void iscsi_rsp_set_resid(struct iscsi_cmd_rsp *rsp,
 				       int32_t resid)
 {
@@ -1128,8 +1143,7 @@ static int iscsi_data_rsp_build(struct iscsi_task *task)
 			rsp->flags |= ISCSI_FLAG_DATA_STATUS;
 			rsp->cmd_status = result;
 			rsp->statsn = cpu_to_be32(conn->stat_sn++);
-			iscsi_rsp_set_residual((struct iscsi_cmd_rsp *) rsp,
-					       &task->scmd);
+			iscsi_set_data_rsp_residual(rsp, &task->scmd);
 		}
 	} else
 		datalen = maxdatalen;
-- 
1.7.9.6

--
To unsubscribe from this list: send the line "unsubscribe stgt" in
the body of a message to majordomo at vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html