include/scsi/iscsi_proto.h - kernel/msm-4.9 - Gitiles

 /*
  * RFC 3720 (iSCSI) protocol data types
  *
  * Copyright (C) 2005 Dmitry Yusupov
  * Copyright (C) 2005 Alex Aizman
  * maintained by open-iscsi@googlegroups.com
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published
  * by the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  * General Public License for more details.
  *
  * See the file COPYING included with this distribution for more details.
  */

 #ifndef ISCSI_PROTO_H
 #define ISCSI_PROTO_H

 #include <linux/types.h>
 #include <scsi/scsi.h>

 #define ISCSI_DRAFT20_VERSION	0x00

 /* default iSCSI listen port for incoming connections */
 #define ISCSI_LISTEN_PORT	3260

 /* iSCSI header length */
 #define ISCSI_HDR_LEN		48

 /* iSCSI CRC32C length */
 #define ISCSI_CRC_LEN		4

 /* Padding word length */
 #define ISCSI_PAD_LEN		4

 /*
  * Serial Number Arithmetic, 32 bits, RFC1982
  */

 static inline int iscsi_sna_lt(u32 n1, u32 n2)
 {
 	return (s32)(n1 - n2) < 0;
 }

 static inline int iscsi_sna_lte(u32 n1, u32 n2)
 {
 	return (s32)(n1 - n2) <= 0;
 }

 static inline int iscsi_sna_gt(u32 n1, u32 n2)
 {
 	return (s32)(n1 - n2) > 0;
 }

 static inline int iscsi_sna_gte(u32 n1, u32 n2)
 {
 	return (s32)(n1 - n2) >= 0;
 }

 /*
  * useful common(control and data pathes) macro
  */
 #define ntoh24(p) (((p)[0] << 16) | ((p)[1] << 8) | ((p)[2]))
 #define hton24(p, v) { \
         p[0] = (((v) >> 16) & 0xFF); \
         p[1] = (((v) >> 8) & 0xFF); \
         p[2] = ((v) & 0xFF); \
 }
 #define zero_data(p) {p[0]=0;p[1]=0;p[2]=0;}

 /* initiator tags; opaque for target */
 typedef uint32_t __bitwise__ itt_t;
 /* below makes sense only for initiator that created this tag */
 #define build_itt(itt, age) ((__force itt_t)\
 	((itt) | ((age) << ISCSI_AGE_SHIFT)))
 #define get_itt(itt) ((__force uint32_t)(itt_t)(itt) & ISCSI_ITT_MASK)
 #define RESERVED_ITT ((__force itt_t)0xffffffff)

 /*
  * iSCSI Template Message Header
  */
 struct iscsi_hdr {
 	uint8_t		opcode;
 	uint8_t		flags;		/* Final bit */
 	uint8_t		rsvd2[2];
 	uint8_t		hlength;	/* AHSs total length */
 	uint8_t		dlength[3];	/* Data length */
 	struct scsi_lun	lun;
 	itt_t		itt;		/* Initiator Task Tag, opaque for target */
 	__be32		ttt;		/* Target Task Tag */
 	__be32		statsn;
 	__be32		exp_statsn;
 	__be32		max_statsn;
 	uint8_t		other[12];
 };

 /************************* RFC 3720 Begin *****************************/

 #define ISCSI_RESERVED_TAG		0xffffffff

 /* Opcode encoding bits */
 #define ISCSI_OP_RETRY			0x80
 #define ISCSI_OP_IMMEDIATE		0x40
 #define ISCSI_OPCODE_MASK		0x3F

 /* Initiator Opcode values */
 #define ISCSI_OP_NOOP_OUT		0x00
 #define ISCSI_OP_SCSI_CMD		0x01
 #define ISCSI_OP_SCSI_TMFUNC		0x02
 #define ISCSI_OP_LOGIN			0x03
 #define ISCSI_OP_TEXT			0x04
 #define ISCSI_OP_SCSI_DATA_OUT		0x05
 #define ISCSI_OP_LOGOUT			0x06
 #define ISCSI_OP_SNACK			0x10

 #define ISCSI_OP_VENDOR1_CMD		0x1c
 #define ISCSI_OP_VENDOR2_CMD		0x1d
 #define ISCSI_OP_VENDOR3_CMD		0x1e
 #define ISCSI_OP_VENDOR4_CMD		0x1f

 /* Target Opcode values */
 #define ISCSI_OP_NOOP_IN		0x20
 #define ISCSI_OP_SCSI_CMD_RSP		0x21
 #define ISCSI_OP_SCSI_TMFUNC_RSP	0x22
 #define ISCSI_OP_LOGIN_RSP		0x23
 #define ISCSI_OP_TEXT_RSP		0x24
 #define ISCSI_OP_SCSI_DATA_IN		0x25
 #define ISCSI_OP_LOGOUT_RSP		0x26
 #define ISCSI_OP_R2T			0x31
 #define ISCSI_OP_ASYNC_EVENT		0x32
 #define ISCSI_OP_REJECT			0x3f

 struct iscsi_ahs_hdr {
 	__be16 ahslength;
 	uint8_t ahstype;
 	uint8_t ahspec[5];
 };

 #define ISCSI_AHSTYPE_CDB		1
 #define ISCSI_AHSTYPE_RLENGTH		2
 #define ISCSI_CDB_SIZE			16

 /* iSCSI PDU Header */
 struct iscsi_scsi_req {
 	uint8_t opcode;
 	uint8_t flags;
 	__be16 rsvd2;
 	uint8_t hlength;
 	uint8_t dlength[3];
 	struct scsi_lun lun;
 	itt_t	 itt;	/* Initiator Task Tag */
 	__be32 data_length;
 	__be32 cmdsn;
 	__be32 exp_statsn;
 	uint8_t cdb[ISCSI_CDB_SIZE];	/* SCSI Command Block */
 	/* Additional Data (Command Dependent) */
 };

 /* Command PDU flags */
 #define ISCSI_FLAG_CMD_FINAL		0x80
 #define ISCSI_FLAG_CMD_READ		0x40
 #define ISCSI_FLAG_CMD_WRITE		0x20
 #define ISCSI_FLAG_CMD_ATTR_MASK	0x07	/* 3 bits */

 /* SCSI Command Attribute values */
 #define ISCSI_ATTR_UNTAGGED		0
 #define ISCSI_ATTR_SIMPLE		1
 #define ISCSI_ATTR_ORDERED		2
 #define ISCSI_ATTR_HEAD_OF_QUEUE	3
 #define ISCSI_ATTR_ACA			4

 struct iscsi_rlength_ahdr {
 	__be16 ahslength;
 	uint8_t ahstype;
 	uint8_t reserved;
 	__be32 read_length;
 };

 /* Extended CDB AHS */
 struct iscsi_ecdb_ahdr {
 	__be16 ahslength;	/* CDB length - 15, including reserved byte */
 	uint8_t ahstype;
 	uint8_t reserved;
 	/* 4-byte aligned extended CDB spillover */
 	uint8_t ecdb[SCSI_MAX_VARLEN_CDB_SIZE - ISCSI_CDB_SIZE];
 };

 /* SCSI Response Header */
 struct iscsi_scsi_rsp {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t response;
 	uint8_t cmd_status;
 	uint8_t hlength;
 	uint8_t dlength[3];
 	uint8_t rsvd[8];
 	itt_t	 itt;	/* Initiator Task Tag */
 	__be32	rsvd1;
 	__be32	statsn;
 	__be32	exp_cmdsn;
 	__be32	max_cmdsn;
 	__be32	exp_datasn;
 	__be32	bi_residual_count;
 	__be32	residual_count;
 	/* Response or Sense Data (optional) */
 };

 /* Command Response PDU flags */
 #define ISCSI_FLAG_CMD_BIDI_OVERFLOW	0x10
 #define ISCSI_FLAG_CMD_BIDI_UNDERFLOW	0x08
 #define ISCSI_FLAG_CMD_OVERFLOW		0x04
 #define ISCSI_FLAG_CMD_UNDERFLOW	0x02

 /* iSCSI Status values. Valid if Rsp Selector bit is not set */
 #define ISCSI_STATUS_CMD_COMPLETED	0
 #define ISCSI_STATUS_TARGET_FAILURE	1
 #define ISCSI_STATUS_SUBSYS_FAILURE	2

 /* Asynchronous Event Header */
 struct iscsi_async {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t rsvd2[2];
 	uint8_t rsvd3;
 	uint8_t dlength[3];
 	struct scsi_lun	lun;
 	uint8_t rsvd4[8];
 	__be32	statsn;
 	__be32	exp_cmdsn;
 	__be32	max_cmdsn;
 	uint8_t async_event;
 	uint8_t async_vcode;
 	__be16	param1;
 	__be16	param2;
 	__be16	param3;
 	uint8_t rsvd5[4];
 };

 /* iSCSI Event Codes */
 #define ISCSI_ASYNC_MSG_SCSI_EVENT			0
 #define ISCSI_ASYNC_MSG_REQUEST_LOGOUT			1
 #define ISCSI_ASYNC_MSG_DROPPING_CONNECTION		2
 #define ISCSI_ASYNC_MSG_DROPPING_ALL_CONNECTIONS	3
 #define ISCSI_ASYNC_MSG_PARAM_NEGOTIATION		4
 #define ISCSI_ASYNC_MSG_VENDOR_SPECIFIC			255

 /* NOP-Out Message */
 struct iscsi_nopout {
 	uint8_t opcode;
 	uint8_t flags;
 	__be16	rsvd2;
 	uint8_t rsvd3;
 	uint8_t dlength[3];
 	struct scsi_lun	lun;
 	itt_t	 itt;	/* Initiator Task Tag */
 	__be32	ttt;	/* Target Transfer Tag */
 	__be32	cmdsn;
 	__be32	exp_statsn;
 	uint8_t rsvd4[16];
 };

 /* NOP-In Message */
 struct iscsi_nopin {
 	uint8_t opcode;
 	uint8_t flags;
 	__be16	rsvd2;
 	uint8_t rsvd3;
 	uint8_t dlength[3];
 	struct scsi_lun	lun;
 	itt_t	 itt;	/* Initiator Task Tag */
 	__be32	ttt;	/* Target Transfer Tag */
 	__be32	statsn;
 	__be32	exp_cmdsn;
 	__be32	max_cmdsn;
 	uint8_t rsvd4[12];
 };

 /* SCSI Task Management Message Header */
 struct iscsi_tm {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t rsvd1[2];
 	uint8_t hlength;
 	uint8_t dlength[3];
 	struct scsi_lun lun;
 	itt_t	 itt;	/* Initiator Task Tag */
 	itt_t	 rtt;	/* Reference Task Tag */
 	__be32	cmdsn;
 	__be32	exp_statsn;
 	__be32	refcmdsn;
 	__be32	exp_datasn;
 	uint8_t rsvd2[8];
 };

 #define ISCSI_FLAG_TM_FUNC_MASK			0x7F

 /* Function values */
 #define ISCSI_TM_FUNC_ABORT_TASK		1
 #define ISCSI_TM_FUNC_ABORT_TASK_SET		2
 #define ISCSI_TM_FUNC_CLEAR_ACA			3
 #define ISCSI_TM_FUNC_CLEAR_TASK_SET		4
 #define ISCSI_TM_FUNC_LOGICAL_UNIT_RESET	5
 #define ISCSI_TM_FUNC_TARGET_WARM_RESET		6
 #define ISCSI_TM_FUNC_TARGET_COLD_RESET		7
 #define ISCSI_TM_FUNC_TASK_REASSIGN		8

 #define ISCSI_TM_FUNC_VALUE(hdr) ((hdr)->flags & ISCSI_FLAG_TM_FUNC_MASK)

 /* SCSI Task Management Response Header */
 struct iscsi_tm_rsp {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t response;	/* see Response values below */
 	uint8_t qualifier;
 	uint8_t hlength;
 	uint8_t dlength[3];
 	uint8_t rsvd2[8];
 	itt_t	 itt;	/* Initiator Task Tag */
 	itt_t	 rtt;	/* Reference Task Tag */
 	__be32	statsn;
 	__be32	exp_cmdsn;
 	__be32	max_cmdsn;
 	uint8_t rsvd3[12];
 };

 /* Response values */
 #define ISCSI_TMF_RSP_COMPLETE		0x00
 #define ISCSI_TMF_RSP_NO_TASK		0x01
 #define ISCSI_TMF_RSP_NO_LUN		0x02
 #define ISCSI_TMF_RSP_TASK_ALLEGIANT	0x03
 #define ISCSI_TMF_RSP_NO_FAILOVER	0x04
 #define ISCSI_TMF_RSP_NOT_SUPPORTED	0x05
 #define ISCSI_TMF_RSP_AUTH_FAILED	0x06
 #define ISCSI_TMF_RSP_REJECTED		0xff

 /* Ready To Transfer Header */
 struct iscsi_r2t_rsp {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t rsvd2[2];
 	uint8_t	hlength;
 	uint8_t	dlength[3];
 	struct scsi_lun	lun;
 	itt_t	 itt;	/* Initiator Task Tag */
 	__be32	ttt;	/* Target Transfer Tag */
 	__be32	statsn;
 	__be32	exp_cmdsn;
 	__be32	max_cmdsn;
 	__be32	r2tsn;
 	__be32	data_offset;
 	__be32	data_length;
 };

 /* SCSI Data Hdr */
 struct iscsi_data {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t rsvd2[2];
 	uint8_t rsvd3;
 	uint8_t dlength[3];
 	struct scsi_lun lun;
 	itt_t	 itt;
 	__be32	ttt;
 	__be32	rsvd4;
 	__be32	exp_statsn;
 	__be32	rsvd5;
 	__be32	datasn;
 	__be32	offset;
 	__be32	rsvd6;
 	/* Payload */
 };

 /* SCSI Data Response Hdr */
 struct iscsi_data_rsp {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t rsvd2;
 	uint8_t cmd_status;
 	uint8_t hlength;
 	uint8_t dlength[3];
 	struct scsi_lun	lun;
 	itt_t	 itt;
 	__be32	ttt;
 	__be32	statsn;
 	__be32	exp_cmdsn;
 	__be32	max_cmdsn;
 	__be32	datasn;
 	__be32	offset;
 	__be32	residual_count;
 };

 /* Data Response PDU flags */
 #define ISCSI_FLAG_DATA_ACK		0x40
 #define ISCSI_FLAG_DATA_OVERFLOW	0x04
 #define ISCSI_FLAG_DATA_UNDERFLOW	0x02
 #define ISCSI_FLAG_DATA_STATUS		0x01

 /* Text Header */
 struct iscsi_text {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t rsvd2[2];
 	uint8_t hlength;
 	uint8_t dlength[3];
 	uint8_t rsvd4[8];
 	itt_t	 itt;
 	__be32	ttt;
 	__be32	cmdsn;
 	__be32	exp_statsn;
 	uint8_t rsvd5[16];
 	/* Text - key=value pairs */
 };

 #define ISCSI_FLAG_TEXT_CONTINUE	0x40

 /* Text Response Header */
 struct iscsi_text_rsp {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t rsvd2[2];
 	uint8_t hlength;
 	uint8_t dlength[3];
 	uint8_t rsvd4[8];
 	itt_t	 itt;
 	__be32	ttt;
 	__be32	statsn;
 	__be32	exp_cmdsn;
 	__be32	max_cmdsn;
 	uint8_t rsvd5[12];
 	/* Text Response - key:value pairs */
 };

 /* Login Header */
 struct iscsi_login_req {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t max_version;	/* Max. version supported */
 	uint8_t min_version;	/* Min. version supported */
 	uint8_t hlength;
 	uint8_t dlength[3];
 	uint8_t isid[6];	/* Initiator Session ID */
 	__be16	tsih;	/* Target Session Handle */
 	itt_t	 itt;	/* Initiator Task Tag */
 	__be16	cid;
 	__be16	rsvd3;
 	__be32	cmdsn;
 	__be32	exp_statsn;
 	uint8_t rsvd5[16];
 };

 /* Login PDU flags */
 #define ISCSI_FLAG_LOGIN_TRANSIT		0x80
 #define ISCSI_FLAG_LOGIN_CONTINUE		0x40
 #define ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK	0x0C	/* 2 bits */
 #define ISCSI_FLAG_LOGIN_CURRENT_STAGE1		0x04
 #define ISCSI_FLAG_LOGIN_CURRENT_STAGE2		0x08
 #define ISCSI_FLAG_LOGIN_CURRENT_STAGE3		0x0C
 #define ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK	0x03	/* 2 bits */
 #define ISCSI_FLAG_LOGIN_NEXT_STAGE1		0x01
 #define ISCSI_FLAG_LOGIN_NEXT_STAGE2		0x02
 #define ISCSI_FLAG_LOGIN_NEXT_STAGE3		0x03

 #define ISCSI_LOGIN_CURRENT_STAGE(flags) \
 	((flags & ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK) >> 2)
 #define ISCSI_LOGIN_NEXT_STAGE(flags) \
 	(flags & ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK)

 /* Login Response Header */
 struct iscsi_login_rsp {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t max_version;	/* Max. version supported */
 	uint8_t active_version;	/* Active version */
 	uint8_t hlength;
 	uint8_t dlength[3];
 	uint8_t isid[6];	/* Initiator Session ID */
 	__be16	tsih;	/* Target Session Handle */
 	itt_t	 itt;	/* Initiator Task Tag */
 	__be32	rsvd3;
 	__be32	statsn;
 	__be32	exp_cmdsn;
 	__be32	max_cmdsn;
 	uint8_t status_class;	/* see Login RSP ststus classes below */
 	uint8_t status_detail;	/* see Login RSP Status details below */
 	uint8_t rsvd4[10];
 };

 /* Login stage (phase) codes for CSG, NSG */
 #define ISCSI_INITIAL_LOGIN_STAGE		-1
 #define ISCSI_SECURITY_NEGOTIATION_STAGE	0
 #define ISCSI_OP_PARMS_NEGOTIATION_STAGE	1
 #define ISCSI_FULL_FEATURE_PHASE		3

 /* Login Status response classes */
 #define ISCSI_STATUS_CLS_SUCCESS		0x00
 #define ISCSI_STATUS_CLS_REDIRECT		0x01
 #define ISCSI_STATUS_CLS_INITIATOR_ERR		0x02
 #define ISCSI_STATUS_CLS_TARGET_ERR		0x03

 /* Login Status response detail codes */
 /* Class-0 (Success) */
 #define ISCSI_LOGIN_STATUS_ACCEPT		0x00

 /* Class-1 (Redirection) */
 #define ISCSI_LOGIN_STATUS_TGT_MOVED_TEMP	0x01
 #define ISCSI_LOGIN_STATUS_TGT_MOVED_PERM	0x02

 /* Class-2 (Initiator Error) */
 #define ISCSI_LOGIN_STATUS_INIT_ERR		0x00
 #define ISCSI_LOGIN_STATUS_AUTH_FAILED		0x01
 #define ISCSI_LOGIN_STATUS_TGT_FORBIDDEN	0x02
 #define ISCSI_LOGIN_STATUS_TGT_NOT_FOUND	0x03
 #define ISCSI_LOGIN_STATUS_TGT_REMOVED		0x04
 #define ISCSI_LOGIN_STATUS_NO_VERSION		0x05
 #define ISCSI_LOGIN_STATUS_ISID_ERROR		0x06
 #define ISCSI_LOGIN_STATUS_MISSING_FIELDS	0x07
 #define ISCSI_LOGIN_STATUS_CONN_ADD_FAILED	0x08
 #define ISCSI_LOGIN_STATUS_NO_SESSION_TYPE	0x09
 #define ISCSI_LOGIN_STATUS_NO_SESSION		0x0a
 #define ISCSI_LOGIN_STATUS_INVALID_REQUEST	0x0b

 /* Class-3 (Target Error) */
 #define ISCSI_LOGIN_STATUS_TARGET_ERROR		0x00
 #define ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE	0x01
 #define ISCSI_LOGIN_STATUS_NO_RESOURCES		0x02

 /* Logout Header */
 struct iscsi_logout {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t rsvd1[2];
 	uint8_t hlength;
 	uint8_t dlength[3];
 	uint8_t rsvd2[8];
 	itt_t	 itt;	/* Initiator Task Tag */
 	__be16	cid;
 	uint8_t rsvd3[2];
 	__be32	cmdsn;
 	__be32	exp_statsn;
 	uint8_t rsvd4[16];
 };

 /* Logout PDU flags */
 #define ISCSI_FLAG_LOGOUT_REASON_MASK	0x7F

 /* logout reason_code values */

 #define ISCSI_LOGOUT_REASON_CLOSE_SESSION	0
 #define ISCSI_LOGOUT_REASON_CLOSE_CONNECTION	1
 #define ISCSI_LOGOUT_REASON_RECOVERY		2
 #define ISCSI_LOGOUT_REASON_AEN_REQUEST		3

 /* Logout Response Header */
 struct iscsi_logout_rsp {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t response;	/* see Logout response values below */
 	uint8_t rsvd2;
 	uint8_t hlength;
 	uint8_t dlength[3];
 	uint8_t rsvd3[8];
 	itt_t	 itt;	/* Initiator Task Tag */
 	__be32	rsvd4;
 	__be32	statsn;
 	__be32	exp_cmdsn;
 	__be32	max_cmdsn;
 	__be32	rsvd5;
 	__be16	t2wait;
 	__be16	t2retain;
 	__be32	rsvd6;
 };

 /* logout response status values */

 #define ISCSI_LOGOUT_SUCCESS			0
 #define ISCSI_LOGOUT_CID_NOT_FOUND		1
 #define ISCSI_LOGOUT_RECOVERY_UNSUPPORTED	2
 #define ISCSI_LOGOUT_CLEANUP_FAILED		3

 /* SNACK Header */
 struct iscsi_snack {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t rsvd2[2];
 	uint8_t hlength;
 	uint8_t dlength[3];
 	uint8_t lun[8];
 	itt_t	 itt;
 	__be32  ttt;
 	uint8_t rsvd3[4];
 	__be32  exp_statsn;
 	uint8_t rsvd4[8];
 	__be32	begrun;
 	__be32	runlength;
 };

 /* SNACK PDU flags */
 #define ISCSI_FLAG_SNACK_TYPE_DATA		0
 #define ISCSI_FLAG_SNACK_TYPE_R2T		0
 #define ISCSI_FLAG_SNACK_TYPE_STATUS		1
 #define ISCSI_FLAG_SNACK_TYPE_DATA_ACK		2
 #define ISCSI_FLAG_SNACK_TYPE_RDATA		3
 #define ISCSI_FLAG_SNACK_TYPE_MASK	0x0F	/* 4 bits */

 /* Reject Message Header */
 struct iscsi_reject {
 	uint8_t opcode;
 	uint8_t flags;
 	uint8_t reason;
 	uint8_t rsvd2;
 	uint8_t hlength;
 	uint8_t dlength[3];
 	uint8_t rsvd3[8];
 	__be32  ffffffff;
 	uint8_t rsvd4[4];
 	__be32	statsn;
 	__be32	exp_cmdsn;
 	__be32	max_cmdsn;
 	__be32	datasn;
 	uint8_t rsvd5[8];
 	/* Text - Rejected hdr */
 };

 /* Reason for Reject */
 #define ISCSI_REASON_CMD_BEFORE_LOGIN	1
 #define ISCSI_REASON_DATA_DIGEST_ERROR	2
 #define ISCSI_REASON_DATA_SNACK_REJECT	3
 #define ISCSI_REASON_PROTOCOL_ERROR	4
 #define ISCSI_REASON_CMD_NOT_SUPPORTED	5
 #define ISCSI_REASON_IMM_CMD_REJECT		6
 #define ISCSI_REASON_TASK_IN_PROGRESS	7
 #define ISCSI_REASON_INVALID_SNACK		8
 #define ISCSI_REASON_BOOKMARK_INVALID	9
 #define ISCSI_REASON_BOOKMARK_NO_RESOURCES	10
 #define ISCSI_REASON_NEGOTIATION_RESET	11

 /* Max. number of Key=Value pairs in a text message */
 #define MAX_KEY_VALUE_PAIRS	8192

 /* maximum length for text keys/values */
 #define KEY_MAXLEN		64
 #define VALUE_MAXLEN		255
 #define TARGET_NAME_MAXLEN	VALUE_MAXLEN

 #define ISCSI_DEF_MAX_RECV_SEG_LEN		8192
 #define ISCSI_MIN_MAX_RECV_SEG_LEN		512
 #define ISCSI_MAX_MAX_RECV_SEG_LEN		16777215

 #define ISCSI_DEF_FIRST_BURST_LEN		65536
 #define ISCSI_MIN_FIRST_BURST_LEN		512
 #define ISCSI_MAX_FIRST_BURST_LEN		16777215

 #define ISCSI_DEF_MAX_BURST_LEN			262144
 #define ISCSI_MIN_MAX_BURST_LEN			512
 #define ISCSI_MAX_MAX_BURST_LEN			16777215

 #define ISCSI_DEF_TIME2WAIT			2

 #define ISCSI_NAME_LEN				224

 /************************* RFC 3720 End *****************************/

 #endif /* ISCSI_PROTO_H */
	/*
	* RFC 3720 (iSCSI) protocol data types
	*
	* Copyright (C) 2005 Dmitry Yusupov
	* Copyright (C) 2005 Alex Aizman
	* maintained by open-iscsi@googlegroups.com
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published
	* by the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License for more details.
	*
	* See the file COPYING included with this distribution for more details.
	*/

	#ifndef ISCSI_PROTO_H
	#define ISCSI_PROTO_H

	#include <linux/types.h>
	#include <scsi/scsi.h>

	#define ISCSI_DRAFT20_VERSION 0x00

	/* default iSCSI listen port for incoming connections */
	#define ISCSI_LISTEN_PORT 3260

	/* iSCSI header length */
	#define ISCSI_HDR_LEN 48

	/* iSCSI CRC32C length */
	#define ISCSI_CRC_LEN 4

	/* Padding word length */
	#define ISCSI_PAD_LEN 4

	/*
	* Serial Number Arithmetic, 32 bits, RFC1982
	*/

	static inline int iscsi_sna_lt(u32 n1, u32 n2)
	{
	return (s32)(n1 - n2) < 0;
	}

	static inline int iscsi_sna_lte(u32 n1, u32 n2)
	{
	return (s32)(n1 - n2) <= 0;
	}

	static inline int iscsi_sna_gt(u32 n1, u32 n2)
	{
	return (s32)(n1 - n2) > 0;
	}

	static inline int iscsi_sna_gte(u32 n1, u32 n2)
	{
	return (s32)(n1 - n2) >= 0;
	}

	/*
	* useful common(control and data pathes) macro
	*/
	#define ntoh24(p) (((p)[0] << 16) \| ((p)[1] << 8) \| ((p)[2]))
	#define hton24(p, v) { \
	p[0] = (((v) >> 16) & 0xFF); \
	p[1] = (((v) >> 8) & 0xFF); \
	p[2] = ((v) & 0xFF); \
	}
	#define zero_data(p) {p[0]=0;p[1]=0;p[2]=0;}

	/* initiator tags; opaque for target */
	typedef uint32_t __bitwise__ itt_t;
	/* below makes sense only for initiator that created this tag */
	#define build_itt(itt, age) ((__force itt_t)\
	((itt) \| ((age) << ISCSI_AGE_SHIFT)))
	#define get_itt(itt) ((__force uint32_t)(itt_t)(itt) & ISCSI_ITT_MASK)
	#define RESERVED_ITT ((__force itt_t)0xffffffff)

	/*
	* iSCSI Template Message Header
	*/
	struct iscsi_hdr {
	uint8_t opcode;
	uint8_t flags; /* Final bit */
	uint8_t rsvd2[2];
	uint8_t hlength; /* AHSs total length */
	uint8_t dlength[3]; /* Data length */
	struct scsi_lun lun;
	itt_t itt; /* Initiator Task Tag, opaque for target */
	__be32 ttt; /* Target Task Tag */
	__be32 statsn;
	__be32 exp_statsn;
	__be32 max_statsn;
	uint8_t other[12];
	};

	/*********************** RFC 3720 Begin ***************************/

	#define ISCSI_RESERVED_TAG 0xffffffff

	/* Opcode encoding bits */
	#define ISCSI_OP_RETRY 0x80
	#define ISCSI_OP_IMMEDIATE 0x40
	#define ISCSI_OPCODE_MASK 0x3F

	/* Initiator Opcode values */
	#define ISCSI_OP_NOOP_OUT 0x00
	#define ISCSI_OP_SCSI_CMD 0x01
	#define ISCSI_OP_SCSI_TMFUNC 0x02
	#define ISCSI_OP_LOGIN 0x03
	#define ISCSI_OP_TEXT 0x04
	#define ISCSI_OP_SCSI_DATA_OUT 0x05
	#define ISCSI_OP_LOGOUT 0x06
	#define ISCSI_OP_SNACK 0x10

	#define ISCSI_OP_VENDOR1_CMD 0x1c
	#define ISCSI_OP_VENDOR2_CMD 0x1d
	#define ISCSI_OP_VENDOR3_CMD 0x1e
	#define ISCSI_OP_VENDOR4_CMD 0x1f

	/* Target Opcode values */
	#define ISCSI_OP_NOOP_IN 0x20
	#define ISCSI_OP_SCSI_CMD_RSP 0x21
	#define ISCSI_OP_SCSI_TMFUNC_RSP 0x22
	#define ISCSI_OP_LOGIN_RSP 0x23
	#define ISCSI_OP_TEXT_RSP 0x24
	#define ISCSI_OP_SCSI_DATA_IN 0x25
	#define ISCSI_OP_LOGOUT_RSP 0x26
	#define ISCSI_OP_R2T 0x31
	#define ISCSI_OP_ASYNC_EVENT 0x32
	#define ISCSI_OP_REJECT 0x3f

	struct iscsi_ahs_hdr {
	__be16 ahslength;
	uint8_t ahstype;
	uint8_t ahspec[5];
	};

	#define ISCSI_AHSTYPE_CDB 1
	#define ISCSI_AHSTYPE_RLENGTH 2
	#define ISCSI_CDB_SIZE 16

	/* iSCSI PDU Header */
	struct iscsi_scsi_req {
	uint8_t opcode;
	uint8_t flags;
	__be16 rsvd2;
	uint8_t hlength;
	uint8_t dlength[3];
	struct scsi_lun lun;
	itt_t itt; /* Initiator Task Tag */
	__be32 data_length;
	__be32 cmdsn;
	__be32 exp_statsn;
	uint8_t cdb[ISCSI_CDB_SIZE]; /* SCSI Command Block */
	/* Additional Data (Command Dependent) */
	};

	/* Command PDU flags */
	#define ISCSI_FLAG_CMD_FINAL 0x80
	#define ISCSI_FLAG_CMD_READ 0x40
	#define ISCSI_FLAG_CMD_WRITE 0x20
	#define ISCSI_FLAG_CMD_ATTR_MASK 0x07 /* 3 bits */

	/* SCSI Command Attribute values */
	#define ISCSI_ATTR_UNTAGGED 0
	#define ISCSI_ATTR_SIMPLE 1
	#define ISCSI_ATTR_ORDERED 2
	#define ISCSI_ATTR_HEAD_OF_QUEUE 3
	#define ISCSI_ATTR_ACA 4

	struct iscsi_rlength_ahdr {
	__be16 ahslength;
	uint8_t ahstype;
	uint8_t reserved;
	__be32 read_length;
	};

	/* Extended CDB AHS */
	struct iscsi_ecdb_ahdr {
	__be16 ahslength; /* CDB length - 15, including reserved byte */
	uint8_t ahstype;
	uint8_t reserved;
	/* 4-byte aligned extended CDB spillover */
	uint8_t ecdb[SCSI_MAX_VARLEN_CDB_SIZE - ISCSI_CDB_SIZE];
	};

	/* SCSI Response Header */
	struct iscsi_scsi_rsp {
	uint8_t opcode;
	uint8_t flags;
	uint8_t response;
	uint8_t cmd_status;
	uint8_t hlength;
	uint8_t dlength[3];
	uint8_t rsvd[8];
	itt_t itt; /* Initiator Task Tag */
	__be32 rsvd1;
	__be32 statsn;
	__be32 exp_cmdsn;
	__be32 max_cmdsn;
	__be32 exp_datasn;
	__be32 bi_residual_count;
	__be32 residual_count;
	/* Response or Sense Data (optional) */
	};

	/* Command Response PDU flags */
	#define ISCSI_FLAG_CMD_BIDI_OVERFLOW 0x10
	#define ISCSI_FLAG_CMD_BIDI_UNDERFLOW 0x08
	#define ISCSI_FLAG_CMD_OVERFLOW 0x04
	#define ISCSI_FLAG_CMD_UNDERFLOW 0x02

	/* iSCSI Status values. Valid if Rsp Selector bit is not set */
	#define ISCSI_STATUS_CMD_COMPLETED 0
	#define ISCSI_STATUS_TARGET_FAILURE 1
	#define ISCSI_STATUS_SUBSYS_FAILURE 2

	/* Asynchronous Event Header */
	struct iscsi_async {
	uint8_t opcode;
	uint8_t flags;
	uint8_t rsvd2[2];
	uint8_t rsvd3;
	uint8_t dlength[3];
	struct scsi_lun lun;
	uint8_t rsvd4[8];
	__be32 statsn;
	__be32 exp_cmdsn;
	__be32 max_cmdsn;
	uint8_t async_event;
	uint8_t async_vcode;
	__be16 param1;
	__be16 param2;
	__be16 param3;
	uint8_t rsvd5[4];
	};

	/* iSCSI Event Codes */
	#define ISCSI_ASYNC_MSG_SCSI_EVENT 0
	#define ISCSI_ASYNC_MSG_REQUEST_LOGOUT 1
	#define ISCSI_ASYNC_MSG_DROPPING_CONNECTION 2
	#define ISCSI_ASYNC_MSG_DROPPING_ALL_CONNECTIONS 3
	#define ISCSI_ASYNC_MSG_PARAM_NEGOTIATION 4
	#define ISCSI_ASYNC_MSG_VENDOR_SPECIFIC 255

	/* NOP-Out Message */
	struct iscsi_nopout {
	uint8_t opcode;
	uint8_t flags;
	__be16 rsvd2;
	uint8_t rsvd3;
	uint8_t dlength[3];
	struct scsi_lun lun;
	itt_t itt; /* Initiator Task Tag */
	__be32 ttt; /* Target Transfer Tag */
	__be32 cmdsn;
	__be32 exp_statsn;
	uint8_t rsvd4[16];
	};

	/* NOP-In Message */
	struct iscsi_nopin {
	uint8_t opcode;
	uint8_t flags;
	__be16 rsvd2;
	uint8_t rsvd3;
	uint8_t dlength[3];
	struct scsi_lun lun;
	itt_t itt; /* Initiator Task Tag */
	__be32 ttt; /* Target Transfer Tag */
	__be32 statsn;
	__be32 exp_cmdsn;
	__be32 max_cmdsn;
	uint8_t rsvd4[12];
	};

	/* SCSI Task Management Message Header */
	struct iscsi_tm {
	uint8_t opcode;
	uint8_t flags;
	uint8_t rsvd1[2];
	uint8_t hlength;
	uint8_t dlength[3];
	struct scsi_lun lun;
	itt_t itt; /* Initiator Task Tag */
	itt_t rtt; /* Reference Task Tag */
	__be32 cmdsn;
	__be32 exp_statsn;
	__be32 refcmdsn;
	__be32 exp_datasn;
	uint8_t rsvd2[8];
	};

	#define ISCSI_FLAG_TM_FUNC_MASK 0x7F

	/* Function values */
	#define ISCSI_TM_FUNC_ABORT_TASK 1
	#define ISCSI_TM_FUNC_ABORT_TASK_SET 2
	#define ISCSI_TM_FUNC_CLEAR_ACA 3
	#define ISCSI_TM_FUNC_CLEAR_TASK_SET 4
	#define ISCSI_TM_FUNC_LOGICAL_UNIT_RESET 5
	#define ISCSI_TM_FUNC_TARGET_WARM_RESET 6
	#define ISCSI_TM_FUNC_TARGET_COLD_RESET 7
	#define ISCSI_TM_FUNC_TASK_REASSIGN 8

	#define ISCSI_TM_FUNC_VALUE(hdr) ((hdr)->flags & ISCSI_FLAG_TM_FUNC_MASK)

	/* SCSI Task Management Response Header */
	struct iscsi_tm_rsp {
	uint8_t opcode;
	uint8_t flags;
	uint8_t response; /* see Response values below */
	uint8_t qualifier;
	uint8_t hlength;
	uint8_t dlength[3];
	uint8_t rsvd2[8];
	itt_t itt; /* Initiator Task Tag */
	itt_t rtt; /* Reference Task Tag */
	__be32 statsn;
	__be32 exp_cmdsn;
	__be32 max_cmdsn;
	uint8_t rsvd3[12];
	};

	/* Response values */
	#define ISCSI_TMF_RSP_COMPLETE 0x00
	#define ISCSI_TMF_RSP_NO_TASK 0x01
	#define ISCSI_TMF_RSP_NO_LUN 0x02
	#define ISCSI_TMF_RSP_TASK_ALLEGIANT 0x03
	#define ISCSI_TMF_RSP_NO_FAILOVER 0x04
	#define ISCSI_TMF_RSP_NOT_SUPPORTED 0x05
	#define ISCSI_TMF_RSP_AUTH_FAILED 0x06
	#define ISCSI_TMF_RSP_REJECTED 0xff

	/* Ready To Transfer Header */
	struct iscsi_r2t_rsp {
	uint8_t opcode;
	uint8_t flags;
	uint8_t rsvd2[2];
	uint8_t hlength;
	uint8_t dlength[3];
	struct scsi_lun lun;
	itt_t itt; /* Initiator Task Tag */
	__be32 ttt; /* Target Transfer Tag */
	__be32 statsn;
	__be32 exp_cmdsn;
	__be32 max_cmdsn;
	__be32 r2tsn;
	__be32 data_offset;
	__be32 data_length;
	};

	/* SCSI Data Hdr */
	struct iscsi_data {
	uint8_t opcode;
	uint8_t flags;
	uint8_t rsvd2[2];
	uint8_t rsvd3;
	uint8_t dlength[3];
	struct scsi_lun lun;
	itt_t itt;
	__be32 ttt;
	__be32 rsvd4;
	__be32 exp_statsn;
	__be32 rsvd5;
	__be32 datasn;
	__be32 offset;
	__be32 rsvd6;
	/* Payload */
	};

	/* SCSI Data Response Hdr */
	struct iscsi_data_rsp {
	uint8_t opcode;
	uint8_t flags;
	uint8_t rsvd2;
	uint8_t cmd_status;
	uint8_t hlength;
	uint8_t dlength[3];
	struct scsi_lun lun;
	itt_t itt;
	__be32 ttt;
	__be32 statsn;
	__be32 exp_cmdsn;
	__be32 max_cmdsn;
	__be32 datasn;
	__be32 offset;
	__be32 residual_count;
	};

	/* Data Response PDU flags */
	#define ISCSI_FLAG_DATA_ACK 0x40
	#define ISCSI_FLAG_DATA_OVERFLOW 0x04
	#define ISCSI_FLAG_DATA_UNDERFLOW 0x02
	#define ISCSI_FLAG_DATA_STATUS 0x01

	/* Text Header */
	struct iscsi_text {
	uint8_t opcode;
	uint8_t flags;
	uint8_t rsvd2[2];
	uint8_t hlength;
	uint8_t dlength[3];
	uint8_t rsvd4[8];
	itt_t itt;
	__be32 ttt;
	__be32 cmdsn;
	__be32 exp_statsn;
	uint8_t rsvd5[16];
	/* Text - key=value pairs */
	};

	#define ISCSI_FLAG_TEXT_CONTINUE 0x40

	/* Text Response Header */
	struct iscsi_text_rsp {
	uint8_t opcode;
	uint8_t flags;
	uint8_t rsvd2[2];
	uint8_t hlength;
	uint8_t dlength[3];
	uint8_t rsvd4[8];
	itt_t itt;
	__be32 ttt;
	__be32 statsn;
	__be32 exp_cmdsn;
	__be32 max_cmdsn;
	uint8_t rsvd5[12];
	/* Text Response - key:value pairs */
	};

	/* Login Header */
	struct iscsi_login_req {
	uint8_t opcode;
	uint8_t flags;
	uint8_t max_version; /* Max. version supported */
	uint8_t min_version; /* Min. version supported */
	uint8_t hlength;
	uint8_t dlength[3];
	uint8_t isid[6]; /* Initiator Session ID */
	__be16 tsih; /* Target Session Handle */
	itt_t itt; /* Initiator Task Tag */
	__be16 cid;
	__be16 rsvd3;
	__be32 cmdsn;
	__be32 exp_statsn;
	uint8_t rsvd5[16];
	};

	/* Login PDU flags */
	#define ISCSI_FLAG_LOGIN_TRANSIT 0x80
	#define ISCSI_FLAG_LOGIN_CONTINUE 0x40
	#define ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK 0x0C /* 2 bits */
	#define ISCSI_FLAG_LOGIN_CURRENT_STAGE1 0x04
	#define ISCSI_FLAG_LOGIN_CURRENT_STAGE2 0x08
	#define ISCSI_FLAG_LOGIN_CURRENT_STAGE3 0x0C
	#define ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK 0x03 /* 2 bits */
	#define ISCSI_FLAG_LOGIN_NEXT_STAGE1 0x01
	#define ISCSI_FLAG_LOGIN_NEXT_STAGE2 0x02
	#define ISCSI_FLAG_LOGIN_NEXT_STAGE3 0x03

	#define ISCSI_LOGIN_CURRENT_STAGE(flags) \
	((flags & ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK) >> 2)
	#define ISCSI_LOGIN_NEXT_STAGE(flags) \
	(flags & ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK)

	/* Login Response Header */
	struct iscsi_login_rsp {
	uint8_t opcode;
	uint8_t flags;
	uint8_t max_version; /* Max. version supported */
	uint8_t active_version; /* Active version */
	uint8_t hlength;
	uint8_t dlength[3];
	uint8_t isid[6]; /* Initiator Session ID */
	__be16 tsih; /* Target Session Handle */
	itt_t itt; /* Initiator Task Tag */
	__be32 rsvd3;
	__be32 statsn;
	__be32 exp_cmdsn;
	__be32 max_cmdsn;
	uint8_t status_class; /* see Login RSP ststus classes below */
	uint8_t status_detail; /* see Login RSP Status details below */
	uint8_t rsvd4[10];
	};

	/* Login stage (phase) codes for CSG, NSG */
	#define ISCSI_INITIAL_LOGIN_STAGE -1
	#define ISCSI_SECURITY_NEGOTIATION_STAGE 0
	#define ISCSI_OP_PARMS_NEGOTIATION_STAGE 1
	#define ISCSI_FULL_FEATURE_PHASE 3

	/* Login Status response classes */
	#define ISCSI_STATUS_CLS_SUCCESS 0x00
	#define ISCSI_STATUS_CLS_REDIRECT 0x01
	#define ISCSI_STATUS_CLS_INITIATOR_ERR 0x02
	#define ISCSI_STATUS_CLS_TARGET_ERR 0x03

	/* Login Status response detail codes */
	/* Class-0 (Success) */
	#define ISCSI_LOGIN_STATUS_ACCEPT 0x00

	/* Class-1 (Redirection) */
	#define ISCSI_LOGIN_STATUS_TGT_MOVED_TEMP 0x01
	#define ISCSI_LOGIN_STATUS_TGT_MOVED_PERM 0x02

	/* Class-2 (Initiator Error) */
	#define ISCSI_LOGIN_STATUS_INIT_ERR 0x00
	#define ISCSI_LOGIN_STATUS_AUTH_FAILED 0x01
	#define ISCSI_LOGIN_STATUS_TGT_FORBIDDEN 0x02
	#define ISCSI_LOGIN_STATUS_TGT_NOT_FOUND 0x03
	#define ISCSI_LOGIN_STATUS_TGT_REMOVED 0x04
	#define ISCSI_LOGIN_STATUS_NO_VERSION 0x05
	#define ISCSI_LOGIN_STATUS_ISID_ERROR 0x06
	#define ISCSI_LOGIN_STATUS_MISSING_FIELDS 0x07
	#define ISCSI_LOGIN_STATUS_CONN_ADD_FAILED 0x08
	#define ISCSI_LOGIN_STATUS_NO_SESSION_TYPE 0x09
	#define ISCSI_LOGIN_STATUS_NO_SESSION 0x0a
	#define ISCSI_LOGIN_STATUS_INVALID_REQUEST 0x0b

	/* Class-3 (Target Error) */
	#define ISCSI_LOGIN_STATUS_TARGET_ERROR 0x00
	#define ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE 0x01
	#define ISCSI_LOGIN_STATUS_NO_RESOURCES 0x02

	/* Logout Header */
	struct iscsi_logout {
	uint8_t opcode;
	uint8_t flags;
	uint8_t rsvd1[2];
	uint8_t hlength;
	uint8_t dlength[3];
	uint8_t rsvd2[8];
	itt_t itt; /* Initiator Task Tag */
	__be16 cid;
	uint8_t rsvd3[2];
	__be32 cmdsn;
	__be32 exp_statsn;
	uint8_t rsvd4[16];
	};

	/* Logout PDU flags */
	#define ISCSI_FLAG_LOGOUT_REASON_MASK 0x7F

	/* logout reason_code values */

	#define ISCSI_LOGOUT_REASON_CLOSE_SESSION 0
	#define ISCSI_LOGOUT_REASON_CLOSE_CONNECTION 1
	#define ISCSI_LOGOUT_REASON_RECOVERY 2
	#define ISCSI_LOGOUT_REASON_AEN_REQUEST 3

	/* Logout Response Header */
	struct iscsi_logout_rsp {
	uint8_t opcode;
	uint8_t flags;
	uint8_t response; /* see Logout response values below */
	uint8_t rsvd2;
	uint8_t hlength;
	uint8_t dlength[3];
	uint8_t rsvd3[8];
	itt_t itt; /* Initiator Task Tag */
	__be32 rsvd4;
	__be32 statsn;
	__be32 exp_cmdsn;
	__be32 max_cmdsn;
	__be32 rsvd5;
	__be16 t2wait;
	__be16 t2retain;
	__be32 rsvd6;
	};

	/* logout response status values */

	#define ISCSI_LOGOUT_SUCCESS 0
	#define ISCSI_LOGOUT_CID_NOT_FOUND 1
	#define ISCSI_LOGOUT_RECOVERY_UNSUPPORTED 2
	#define ISCSI_LOGOUT_CLEANUP_FAILED 3

	/* SNACK Header */
	struct iscsi_snack {
	uint8_t opcode;
	uint8_t flags;
	uint8_t rsvd2[2];
	uint8_t hlength;
	uint8_t dlength[3];
	uint8_t lun[8];
	itt_t itt;
	__be32 ttt;
	uint8_t rsvd3[4];
	__be32 exp_statsn;
	uint8_t rsvd4[8];
	__be32 begrun;
	__be32 runlength;
	};

	/* SNACK PDU flags */
	#define ISCSI_FLAG_SNACK_TYPE_DATA 0
	#define ISCSI_FLAG_SNACK_TYPE_R2T 0
	#define ISCSI_FLAG_SNACK_TYPE_STATUS 1
	#define ISCSI_FLAG_SNACK_TYPE_DATA_ACK 2
	#define ISCSI_FLAG_SNACK_TYPE_RDATA 3
	#define ISCSI_FLAG_SNACK_TYPE_MASK 0x0F /* 4 bits */

	/* Reject Message Header */
	struct iscsi_reject {
	uint8_t opcode;
	uint8_t flags;
	uint8_t reason;
	uint8_t rsvd2;
	uint8_t hlength;
	uint8_t dlength[3];
	uint8_t rsvd3[8];
	__be32 ffffffff;
	uint8_t rsvd4[4];
	__be32 statsn;
	__be32 exp_cmdsn;
	__be32 max_cmdsn;
	__be32 datasn;
	uint8_t rsvd5[8];
	/* Text - Rejected hdr */
	};

	/* Reason for Reject */
	#define ISCSI_REASON_CMD_BEFORE_LOGIN 1
	#define ISCSI_REASON_DATA_DIGEST_ERROR 2
	#define ISCSI_REASON_DATA_SNACK_REJECT 3
	#define ISCSI_REASON_PROTOCOL_ERROR 4
	#define ISCSI_REASON_CMD_NOT_SUPPORTED 5
	#define ISCSI_REASON_IMM_CMD_REJECT 6
	#define ISCSI_REASON_TASK_IN_PROGRESS 7
	#define ISCSI_REASON_INVALID_SNACK 8
	#define ISCSI_REASON_BOOKMARK_INVALID 9
	#define ISCSI_REASON_BOOKMARK_NO_RESOURCES 10
	#define ISCSI_REASON_NEGOTIATION_RESET 11

	/* Max. number of Key=Value pairs in a text message */
	#define MAX_KEY_VALUE_PAIRS 8192

	/* maximum length for text keys/values */
	#define KEY_MAXLEN 64
	#define VALUE_MAXLEN 255
	#define TARGET_NAME_MAXLEN VALUE_MAXLEN

	#define ISCSI_DEF_MAX_RECV_SEG_LEN 8192
	#define ISCSI_MIN_MAX_RECV_SEG_LEN 512
	#define ISCSI_MAX_MAX_RECV_SEG_LEN 16777215

	#define ISCSI_DEF_FIRST_BURST_LEN 65536
	#define ISCSI_MIN_FIRST_BURST_LEN 512
	#define ISCSI_MAX_FIRST_BURST_LEN 16777215

	#define ISCSI_DEF_MAX_BURST_LEN 262144
	#define ISCSI_MIN_MAX_BURST_LEN 512
	#define ISCSI_MAX_MAX_BURST_LEN 16777215

	#define ISCSI_DEF_TIME2WAIT 2

	#define ISCSI_NAME_LEN 224

	/*********************** RFC 3720 End ***************************/

	#endif /* ISCSI_PROTO_H */