[SCSI] libiscsi, iscsi_tcp, iscsi_iser: check that burst lengths are valid.

iSCSI RFC states that the first burst length must be smaller than the
max burst length. We currently assume targets will be good, but that may
not be the case, so this patch adds a check.

This patch also moves the unsol data out offset to the lib so the LLDs
do not have to track it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
index 41904f6..4900650 100644
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -102,6 +102,8 @@
 	uint32_t		unsol_datasn;
 	int			imm_count;	/* imm-data (bytes)   */
 	int			unsol_count;	/* unsolicited (bytes)*/
+	/* offset in unsolicited stream (bytes); */
+	int			unsol_offset;
 	int			data_count;	/* remaining Data-Out */
 	struct scsi_cmnd	*sc;		/* associated SCSI cmd*/
 	int			total_length;
@@ -290,8 +292,7 @@
 extern int iscsi_check_assign_cmdsn(struct iscsi_session *,
 				    struct iscsi_nopin *);
 extern void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *,
-					struct iscsi_data *hdr,
-					int transport_data_cnt);
+					struct iscsi_data *hdr);
 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
 				char *, uint32_t);
 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,