[deliverable/linux.git] / include / scsi / libiscsi.h

/*
 * iSCSI lib definitions
 *
 * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
 * Copyright (C) 2004 - 2006 Mike Christie
 * Copyright (C) 2004 - 2005 Dmitry Yusupov
 * Copyright (C) 2004 - 2005 Alex Aizman
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */
#ifndef LIBISCSI_H
#define LIBISCSI_H

#include <linux/types.h>
#include <linux/wait.h>
#include <linux/mutex.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <linux/kfifo.h>
#include <scsi/iscsi_proto.h>
#include <scsi/iscsi_if.h>
#include <scsi/scsi_transport_iscsi.h>

struct scsi_transport_template;
struct scsi_host_template;
struct scsi_device;
struct Scsi_Host;
struct scsi_target;
struct scsi_cmnd;
struct socket;
struct iscsi_transport;
struct iscsi_cls_session;
struct iscsi_cls_conn;
struct iscsi_session;
struct iscsi_nopin;
struct device;

#define ISCSI_DEF_XMIT_CMDS_MAX	128	/* must be power of 2 */
#define ISCSI_MGMT_CMDS_MAX	15

#define ISCSI_DEF_CMD_PER_LUN	32

/* Task Mgmt states */
enum {
	TMF_INITIAL,
	TMF_QUEUED,
	TMF_SUCCESS,
	TMF_FAILED,
	TMF_TIMEDOUT,
	TMF_NOT_FOUND,
};

#define ISID_SIZE			6

/* Connection suspend "bit" */
#define ISCSI_SUSPEND_BIT		1

#define ISCSI_ITT_MASK			0x1fff
#define ISCSI_TOTAL_CMDS_MAX		4096
/* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
#define ISCSI_TOTAL_CMDS_MIN		16
#define ISCSI_AGE_SHIFT			28
#define ISCSI_AGE_MASK			0xf

#define ISCSI_ADDRESS_BUF_LEN		64

enum {
	/* this is the maximum possible storage for AHSs */
	ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
				sizeof(struct iscsi_rlength_ahdr),
	ISCSI_DIGEST_SIZE = sizeof(__u32),
};


enum {
	ISCSI_TASK_FREE,
	ISCSI_TASK_COMPLETED,
	ISCSI_TASK_PENDING,
	ISCSI_TASK_RUNNING,
	ISCSI_TASK_ABRT_TMF,		/* aborted due to TMF */
	ISCSI_TASK_ABRT_SESS_RECOV,	/* aborted due to session recovery */
	ISCSI_TASK_REQUEUE_SCSIQ,	/* qcmd requeueing to scsi-ml */
};

struct iscsi_r2t_info {
	__be32			ttt;		/* copied from R2T */
	__be32			exp_statsn;	/* copied from R2T */
	uint32_t		data_length;	/* copied from R2T */
	uint32_t		data_offset;	/* copied from R2T */
	int			data_count;	/* DATA-Out payload progress */
	int			datasn;
	/* LLDs should set/update these values */
	int			sent;		/* R2T sequence progress */
};

struct iscsi_task {
	/*
	 * Because LLDs allocate their hdr differently, this is a pointer
	 * and length to that storage. It must be setup at session
	 * creation time.
	 */
	struct iscsi_hdr	*hdr;
	unsigned short		hdr_max;
	unsigned short		hdr_len;	/* accumulated size of hdr used */
	/* copied values in case we need to send tmfs */
	itt_t			hdr_itt;
	__be32			cmdsn;
	struct scsi_lun		lun;

	int			itt;		/* this ITT */

	unsigned		imm_count;	/* imm-data (bytes)   */
	/* offset in unsolicited stream (bytes); */
	struct iscsi_r2t_info	unsol_r2t;
	char			*data;		/* mgmt payload */
	unsigned		data_count;
	struct scsi_cmnd	*sc;		/* associated SCSI cmd*/
	struct iscsi_conn	*conn;		/* used connection    */

	/* data processing tracking */
	unsigned long		last_xfer;
	unsigned long		last_timeout;
	bool			have_checked_conn;
	/* state set/tested under session->lock */
	int			state;
	atomic_t		refcount;
	struct list_head	running;	/* running cmd list */
	void			*dd_data;	/* driver/transport data */
};

static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
{
	return task->unsol_r2t.data_length > task->unsol_r2t.sent;
}

static inline void* iscsi_next_hdr(struct iscsi_task *task)
{
	return (void*)task->hdr + task->hdr_len;
}

/* Connection's states */
enum {
	ISCSI_CONN_INITIAL_STAGE,
	ISCSI_CONN_STARTED,
	ISCSI_CONN_STOPPED,
	ISCSI_CONN_CLEANUP_WAIT,
};

struct iscsi_conn {
	struct iscsi_cls_conn	*cls_conn;	/* ptr to class connection */
	void			*dd_data;	/* iscsi_transport data */
	struct iscsi_session	*session;	/* parent session */
	/*
	 * conn_stop() flag: stop to recover, stop to terminate
	 */
        int			stop_stage;
	struct timer_list	transport_timer;
	unsigned long		last_recv;
	unsigned long		last_ping;
	int			ping_timeout;
	int			recv_timeout;
	struct iscsi_task 	*ping_task;

	/* iSCSI connection-wide sequencing */
	uint32_t		exp_statsn;
	uint32_t		statsn;

	/* control data */
	int			id;		/* CID */
	int			c_stage;	/* connection state */
	/*
	 * Preallocated buffer for pdus that have data but do not
	 * originate from scsi-ml. We never have two pdus using the
	 * buffer at the same time. It is only allocated to
	 * the default max recv size because the pdus we support
	 * should always fit in this buffer
	 */
	char			*data;
	struct iscsi_task 	*login_task;	/* mtask used for login/text */
	struct iscsi_task	*task;		/* xmit task in progress */

	/* xmit */
	struct list_head	mgmtqueue;	/* mgmt (control) xmit queue */
	struct list_head	cmdqueue;	/* data-path cmd queue */
	struct list_head	requeue;	/* tasks needing another run */
	struct work_struct	xmitwork;	/* per-conn. xmit workqueue */
	unsigned long		suspend_tx;	/* suspend Tx */
	unsigned long		suspend_rx;	/* suspend Rx */

	/* abort */
	wait_queue_head_t	ehwait;		/* used in eh_abort() */
	struct iscsi_tm		tmhdr;
	struct timer_list	tmf_timer;
	int			tmf_state;	/* see TMF_INITIAL, etc.*/

	/* negotiated params */
	unsigned		max_recv_dlength; /* initiator_max_recv_dsl*/
	unsigned		max_xmit_dlength; /* target_max_recv_dsl */
	int			hdrdgst_en;
	int			datadgst_en;
	int			ifmarker_en;
	int			ofmarker_en;
	/* values userspace uses to id a conn */
	int			persistent_port;
	char			*persistent_address;

	unsigned		max_segment_size;
	unsigned		tcp_xmit_wsf;
	unsigned		tcp_recv_wsf;
	uint16_t		keepalive_tmo;
	uint16_t		local_port;
	uint8_t			tcp_timestamp_stat;
	uint8_t			tcp_nagle_disable;
	uint8_t			tcp_wsf_disable;
	uint8_t			tcp_timer_scale;
	uint8_t			tcp_timestamp_en;
	uint8_t			fragment_disable;
	uint8_t			ipv4_tos;
	uint8_t			ipv6_traffic_class;
	uint8_t			ipv6_flow_label;
	uint8_t			is_fw_assigned_ipv6;
	char			*local_ipaddr;

	/* MIB-statistics */
	uint64_t		txdata_octets;
	uint64_t		rxdata_octets;
	uint32_t		scsicmd_pdus_cnt;
	uint32_t		dataout_pdus_cnt;
	uint32_t		scsirsp_pdus_cnt;
	uint32_t		datain_pdus_cnt;
	uint32_t		r2t_pdus_cnt;
	uint32_t		tmfcmd_pdus_cnt;
	int32_t			tmfrsp_pdus_cnt;

	/* custom statistics */
	uint32_t		eh_abort_cnt;
	uint32_t		fmr_unalign_cnt;
};

struct iscsi_pool {
	struct kfifo		queue;		/* FIFO Queue */
	void			**pool;		/* Pool of elements */
	int			max;		/* Max number of elements */
};

/* Session's states */
enum {
	ISCSI_STATE_FREE = 1,
	ISCSI_STATE_LOGGED_IN,
	ISCSI_STATE_FAILED,
	ISCSI_STATE_TERMINATE,
	ISCSI_STATE_IN_RECOVERY,
	ISCSI_STATE_RECOVERY_FAILED,
	ISCSI_STATE_LOGGING_OUT,
};

struct iscsi_session {
	struct iscsi_cls_session *cls_session;
	/*
	 * Syncs up the scsi eh thread with the iscsi eh thread when sending
	 * task management functions. This must be taken before the session
	 * and recv lock.
	 */
	struct mutex		eh_mutex;

	/* iSCSI session-wide sequencing */
	uint32_t		cmdsn;
	uint32_t		exp_cmdsn;
	uint32_t		max_cmdsn;

	/* This tracks the reqs queued into the initiator */
	uint32_t		queued_cmdsn;

	/* configuration */
	int			abort_timeout;
	int			lu_reset_timeout;
	int			tgt_reset_timeout;
	int			initial_r2t_en;
	unsigned short		max_r2t;
	int			imm_data_en;
	unsigned		first_burst;
	unsigned		max_burst;
	int			time2wait;
	int			time2retain;
	int			pdu_inorder_en;
	int			dataseq_inorder_en;
	int			erl;
	int			fast_abort;
	int			tpgt;
	char			*username;
	char			*username_in;
	char			*password;
	char			*password_in;
	char			*targetname;
	char			*targetalias;
	char			*ifacename;
	char			*initiatorname;
	char			*boot_root;
	char			*boot_nic;
	char			*boot_target;
	char			*portal_type;
	char			*discovery_parent_type;
	uint16_t		discovery_parent_idx;
	uint16_t		def_taskmgmt_tmo;
	uint16_t		tsid;
	uint8_t			auto_snd_tgt_disable;
	uint8_t			discovery_sess;
	uint8_t			chap_auth_en;
	uint8_t			discovery_logout_en;
	uint8_t			bidi_chap_en;
	uint8_t			discovery_auth_optional;
	uint8_t			isid[ISID_SIZE];

	/* control data */
	struct iscsi_transport	*tt;
	struct Scsi_Host	*host;
	struct iscsi_conn	*leadconn;	/* leading connection */
	spinlock_t		lock;		/* protects session state, *
						 * sequence numbers,       *
						 * session resources:      *
						 * - cmdpool,		   *
						 * - mgmtpool,		   *
						 * - r2tpool		   */
	int			state;		/* session state           */
	int			age;		/* counts session re-opens */

	int			scsi_cmds_max; 	/* max scsi commands */
	int			cmds_max;	/* size of cmds array */
	struct iscsi_task	**cmds;		/* Original Cmds arr */
	struct iscsi_pool	cmdpool;	/* PDU's pool */
	void			*dd_data;	/* LLD private data */
};

enum {
	ISCSI_HOST_SETUP,
	ISCSI_HOST_REMOVED,
};

struct iscsi_host {
	char			*initiatorname;
	/* hw address or netdev iscsi connection is bound to */
	char			*hwaddress;
	char			*netdev;

	wait_queue_head_t	session_removal_wq;
	/* protects sessions and state */
	spinlock_t		lock;
	int			num_sessions;
	int			state;

	struct workqueue_struct	*workq;
	char			workq_name[20];
};

/*
 * scsi host template
 */
extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth,
				    int reason);
extern int iscsi_eh_abort(struct scsi_cmnd *sc);
extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);

/*
 * iSCSI host helpers.
 */
#define iscsi_host_priv(_shost) \
	(shost_priv(_shost) + sizeof(struct iscsi_host))

extern int iscsi_host_set_param(struct Scsi_Host *shost,
				enum iscsi_host_param param, char *buf,
				int buflen);
extern int iscsi_host_get_param(struct Scsi_Host *shost,
				enum iscsi_host_param param, char *buf);
extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
					  int dd_data_size,
					  bool xmit_can_sleep);
extern void iscsi_host_remove(struct Scsi_Host *shost);
extern void iscsi_host_free(struct Scsi_Host *shost);
extern int iscsi_target_alloc(struct scsi_target *starget);

/*
 * session management
 */
extern struct iscsi_cls_session *
iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
		    uint16_t, int, int, uint32_t, unsigned int);
extern void iscsi_session_teardown(struct iscsi_cls_session *);
extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
			   enum iscsi_param param, char *buf, int buflen);
extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
				   enum iscsi_param param, char *buf);

#define iscsi_session_printk(prefix, _sess, fmt, a...)	\
	iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)

/*
 * connection management
 */
extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
					       int, uint32_t);
extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
extern int iscsi_conn_start(struct iscsi_cls_conn *);
extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
			   int);
extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
extern void iscsi_session_failure(struct iscsi_session *session,
				  enum iscsi_err err);
extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
				enum iscsi_param param, char *buf);
extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
				     enum iscsi_param param, char *buf);
extern void iscsi_suspend_tx(struct iscsi_conn *conn);
extern void iscsi_suspend_queue(struct iscsi_conn *conn);
extern void iscsi_conn_queue_work(struct iscsi_conn *conn);

#define iscsi_conn_printk(prefix, _c, fmt, a...) \
	iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
			      fmt, ##a)

/*
 * pdu and task processing
 */
extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
				    struct iscsi_r2t_info *r2t,
				    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 *,
			      char *, int);
extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
				char *, int);
extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
extern void iscsi_requeue_task(struct iscsi_task *task);
extern void iscsi_put_task(struct iscsi_task *task);
extern void __iscsi_put_task(struct iscsi_task *task);
extern void __iscsi_get_task(struct iscsi_task *task);
extern void iscsi_complete_scsi_task(struct iscsi_task *task,
				     uint32_t exp_cmdsn, uint32_t max_cmdsn);

/*
 * generic helpers
 */
extern void iscsi_pool_free(struct iscsi_pool *);
extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
extern int iscsi_switch_str_param(char **, char *);

/*
 * inline functions to deal with padding.
 */
static inline unsigned int
iscsi_padded(unsigned int len)
{
	return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
}

static inline unsigned int
iscsi_padding(unsigned int len)
{
	len &= (ISCSI_PAD_LEN - 1);
	if (len)
		len = ISCSI_PAD_LEN - len;
	return len;
}

#endif
Commit	Line	Data
	1	/*
	2	* iSCSI lib definitions
	3	*
	4	* Copyright (C) 2006 Red Hat, Inc. All rights reserved.
	5	* Copyright (C) 2004 - 2006 Mike Christie
	6	* Copyright (C) 2004 - 2005 Dmitry Yusupov
	7	* Copyright (C) 2004 - 2005 Alex Aizman
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2 of the License, or
	12	* (at your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	* GNU General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License
	20	* along with this program; if not, write to the Free Software
	21	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	22	*/
	23	#ifndef LIBISCSI_H
	24	#define LIBISCSI_H
	25
	26	#include <linux/types.h>
	27	#include <linux/wait.h>
	28	#include <linux/mutex.h>
	29	#include <linux/timer.h>
	30	#include <linux/workqueue.h>
	31	#include <linux/kfifo.h>
	32	#include <scsi/iscsi_proto.h>
	33	#include <scsi/iscsi_if.h>
	34	#include <scsi/scsi_transport_iscsi.h>
	35
	36	struct scsi_transport_template;
	37	struct scsi_host_template;
	38	struct scsi_device;
	39	struct Scsi_Host;
	40	struct scsi_target;
	41	struct scsi_cmnd;
	42	struct socket;
	43	struct iscsi_transport;
	44	struct iscsi_cls_session;
	45	struct iscsi_cls_conn;
	46	struct iscsi_session;
	47	struct iscsi_nopin;
	48	struct device;
	49
	50	#define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
	51	#define ISCSI_MGMT_CMDS_MAX 15
	52
	53	#define ISCSI_DEF_CMD_PER_LUN 32
	54
	55	/* Task Mgmt states */
	56	enum {
	57	TMF_INITIAL,
	58	TMF_QUEUED,
	59	TMF_SUCCESS,
	60	TMF_FAILED,
	61	TMF_TIMEDOUT,
	62	TMF_NOT_FOUND,
	63	};
	64
	65	#define ISID_SIZE 6
	66
	67	/* Connection suspend "bit" */
	68	#define ISCSI_SUSPEND_BIT 1
	69
	70	#define ISCSI_ITT_MASK 0x1fff
	71	#define ISCSI_TOTAL_CMDS_MAX 4096
	72	/* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
	73	#define ISCSI_TOTAL_CMDS_MIN 16
	74	#define ISCSI_AGE_SHIFT 28
	75	#define ISCSI_AGE_MASK 0xf
	76
	77	#define ISCSI_ADDRESS_BUF_LEN 64
	78
	79	enum {
	80	/* this is the maximum possible storage for AHSs */
	81	ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
	82	sizeof(struct iscsi_rlength_ahdr),
	83	ISCSI_DIGEST_SIZE = sizeof(__u32),
	84	};
	85
	86
	87	enum {
	88	ISCSI_TASK_FREE,
	89	ISCSI_TASK_COMPLETED,
	90	ISCSI_TASK_PENDING,
	91	ISCSI_TASK_RUNNING,
	92	ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */
	93	ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */
	94	ISCSI_TASK_REQUEUE_SCSIQ, /* qcmd requeueing to scsi-ml */
	95	};
	96
	97	struct iscsi_r2t_info {
	98	__be32 ttt; /* copied from R2T */
	99	__be32 exp_statsn; /* copied from R2T */
	100	uint32_t data_length; /* copied from R2T */
	101	uint32_t data_offset; /* copied from R2T */
	102	int data_count; /* DATA-Out payload progress */
	103	int datasn;
	104	/* LLDs should set/update these values */
	105	int sent; /* R2T sequence progress */
	106	};
	107
	108	struct iscsi_task {
	109	/*
	110	* Because LLDs allocate their hdr differently, this is a pointer
	111	* and length to that storage. It must be setup at session
	112	* creation time.
	113	*/
	114	struct iscsi_hdr *hdr;
	115	unsigned short hdr_max;
	116	unsigned short hdr_len; /* accumulated size of hdr used */
	117	/* copied values in case we need to send tmfs */
	118	itt_t hdr_itt;
	119	__be32 cmdsn;
	120	struct scsi_lun lun;
	121
	122	int itt; /* this ITT */
	123
	124	unsigned imm_count; /* imm-data (bytes) */
	125	/* offset in unsolicited stream (bytes); */
	126	struct iscsi_r2t_info unsol_r2t;
	127	char data; / mgmt payload */
	128	unsigned data_count;
	129	struct scsi_cmnd sc; / associated SCSI cmd*/
	130	struct iscsi_conn conn; / used connection */
	131
	132	/* data processing tracking */
	133	unsigned long last_xfer;
	134	unsigned long last_timeout;
	135	bool have_checked_conn;
	136	/* state set/tested under session->lock */
	137	int state;
	138	atomic_t refcount;
	139	struct list_head running; /* running cmd list */
	140	void dd_data; / driver/transport data */
	141	};
	142
	143	static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
	144	{
	145	return task->unsol_r2t.data_length > task->unsol_r2t.sent;
	146	}
	147
	148	static inline void* iscsi_next_hdr(struct iscsi_task *task)
	149	{
	150	return (void*)task->hdr + task->hdr_len;
	151	}
	152
	153	/* Connection's states */
	154	enum {
	155	ISCSI_CONN_INITIAL_STAGE,
	156	ISCSI_CONN_STARTED,
	157	ISCSI_CONN_STOPPED,
	158	ISCSI_CONN_CLEANUP_WAIT,
	159	};
	160
	161	struct iscsi_conn {
	162	struct iscsi_cls_conn cls_conn; / ptr to class connection */
	163	void dd_data; / iscsi_transport data */
	164	struct iscsi_session session; / parent session */
	165	/*
	166	* conn_stop() flag: stop to recover, stop to terminate
	167	*/
	168	int stop_stage;
	169	struct timer_list transport_timer;
	170	unsigned long last_recv;
	171	unsigned long last_ping;
	172	int ping_timeout;
	173	int recv_timeout;
	174	struct iscsi_task *ping_task;
	175
	176	/* iSCSI connection-wide sequencing */
	177	uint32_t exp_statsn;
	178	uint32_t statsn;
	179
	180	/* control data */
	181	int id; /* CID */
	182	int c_stage; /* connection state */
	183	/*
	184	* Preallocated buffer for pdus that have data but do not
	185	* originate from scsi-ml. We never have two pdus using the
	186	* buffer at the same time. It is only allocated to
	187	* the default max recv size because the pdus we support
	188	* should always fit in this buffer
	189	*/
	190	char *data;
	191	struct iscsi_task login_task; / mtask used for login/text */
	192	struct iscsi_task task; / xmit task in progress */
	193
	194	/* xmit */
	195	struct list_head mgmtqueue; /* mgmt (control) xmit queue */
	196	struct list_head cmdqueue; /* data-path cmd queue */
	197	struct list_head requeue; /* tasks needing another run */
	198	struct work_struct xmitwork; /* per-conn. xmit workqueue */
	199	unsigned long suspend_tx; /* suspend Tx */
	200	unsigned long suspend_rx; /* suspend Rx */
	201
	202	/* abort */
	203	wait_queue_head_t ehwait; /* used in eh_abort() */
	204	struct iscsi_tm tmhdr;
	205	struct timer_list tmf_timer;
	206	int tmf_state; /* see TMF_INITIAL, etc.*/
	207
	208	/* negotiated params */
	209	unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
	210	unsigned max_xmit_dlength; /* target_max_recv_dsl */
	211	int hdrdgst_en;
	212	int datadgst_en;
	213	int ifmarker_en;
	214	int ofmarker_en;
	215	/* values userspace uses to id a conn */
	216	int persistent_port;
	217	char *persistent_address;
	218
	219	unsigned max_segment_size;
	220	unsigned tcp_xmit_wsf;
	221	unsigned tcp_recv_wsf;
	222	uint16_t keepalive_tmo;
	223	uint16_t local_port;
	224	uint8_t tcp_timestamp_stat;
	225	uint8_t tcp_nagle_disable;
	226	uint8_t tcp_wsf_disable;
	227	uint8_t tcp_timer_scale;
	228	uint8_t tcp_timestamp_en;
	229	uint8_t fragment_disable;
	230	uint8_t ipv4_tos;
	231	uint8_t ipv6_traffic_class;
	232	uint8_t ipv6_flow_label;
	233	uint8_t is_fw_assigned_ipv6;
	234	char *local_ipaddr;
	235
	236	/* MIB-statistics */
	237	uint64_t txdata_octets;
	238	uint64_t rxdata_octets;
	239	uint32_t scsicmd_pdus_cnt;
	240	uint32_t dataout_pdus_cnt;
	241	uint32_t scsirsp_pdus_cnt;
	242	uint32_t datain_pdus_cnt;
	243	uint32_t r2t_pdus_cnt;
	244	uint32_t tmfcmd_pdus_cnt;
	245	int32_t tmfrsp_pdus_cnt;
	246
	247	/* custom statistics */
	248	uint32_t eh_abort_cnt;
	249	uint32_t fmr_unalign_cnt;
	250	};
	251
	252	struct iscsi_pool {
	253	struct kfifo queue; /* FIFO Queue */
	254	void *pool; / Pool of elements */
	255	int max; /* Max number of elements */
	256	};
	257
	258	/* Session's states */
	259	enum {
	260	ISCSI_STATE_FREE = 1,
	261	ISCSI_STATE_LOGGED_IN,
	262	ISCSI_STATE_FAILED,
	263	ISCSI_STATE_TERMINATE,
	264	ISCSI_STATE_IN_RECOVERY,
	265	ISCSI_STATE_RECOVERY_FAILED,
	266	ISCSI_STATE_LOGGING_OUT,
	267	};
	268
	269	struct iscsi_session {
	270	struct iscsi_cls_session *cls_session;
	271	/*
	272	* Syncs up the scsi eh thread with the iscsi eh thread when sending
	273	* task management functions. This must be taken before the session
	274	* and recv lock.
	275	*/
	276	struct mutex eh_mutex;
	277
	278	/* iSCSI session-wide sequencing */
	279	uint32_t cmdsn;
	280	uint32_t exp_cmdsn;
	281	uint32_t max_cmdsn;
	282
	283	/* This tracks the reqs queued into the initiator */
	284	uint32_t queued_cmdsn;
	285
	286	/* configuration */
	287	int abort_timeout;
	288	int lu_reset_timeout;
	289	int tgt_reset_timeout;
	290	int initial_r2t_en;
	291	unsigned short max_r2t;
	292	int imm_data_en;
	293	unsigned first_burst;
	294	unsigned max_burst;
	295	int time2wait;
	296	int time2retain;
	297	int pdu_inorder_en;
	298	int dataseq_inorder_en;
	299	int erl;
	300	int fast_abort;
	301	int tpgt;
	302	char *username;
	303	char *username_in;
	304	char *password;
	305	char *password_in;
	306	char *targetname;
	307	char *targetalias;
	308	char *ifacename;
	309	char *initiatorname;
	310	char *boot_root;
	311	char *boot_nic;
	312	char *boot_target;
	313	char *portal_type;
	314	char *discovery_parent_type;
	315	uint16_t discovery_parent_idx;
	316	uint16_t def_taskmgmt_tmo;
	317	uint16_t tsid;
	318	uint8_t auto_snd_tgt_disable;
	319	uint8_t discovery_sess;
	320	uint8_t chap_auth_en;
	321	uint8_t discovery_logout_en;
	322	uint8_t bidi_chap_en;
	323	uint8_t discovery_auth_optional;
	324	uint8_t isid[ISID_SIZE];
	325
	326	/* control data */
	327	struct iscsi_transport *tt;
	328	struct Scsi_Host *host;
	329	struct iscsi_conn leadconn; / leading connection */
	330	spinlock_t lock; /* protects session state, *
	331	* sequence numbers, *
	332	* session resources: *
	333	* - cmdpool, *
	334	* - mgmtpool, *
	335	* - r2tpool */
	336	int state; /* session state */
	337	int age; /* counts session re-opens */
	338
	339	int scsi_cmds_max; /* max scsi commands */
	340	int cmds_max; /* size of cmds array */
	341	struct iscsi_task *cmds; / Original Cmds arr */
	342	struct iscsi_pool cmdpool; /* PDU's pool */
	343	void dd_data; / LLD private data */
	344	};
	345
	346	enum {
	347	ISCSI_HOST_SETUP,
	348	ISCSI_HOST_REMOVED,
	349	};
	350
	351	struct iscsi_host {
	352	char *initiatorname;
	353	/* hw address or netdev iscsi connection is bound to */
	354	char *hwaddress;
	355	char *netdev;
	356
	357	wait_queue_head_t session_removal_wq;
	358	/* protects sessions and state */
	359	spinlock_t lock;
	360	int num_sessions;
	361	int state;
	362
	363	struct workqueue_struct *workq;
	364	char workq_name[20];
	365	};
	366
	367	/*
	368	* scsi host template
	369	*/
	370	extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth,
	371	int reason);
	372	extern int iscsi_eh_abort(struct scsi_cmnd *sc);
	373	extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
	374	extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
	375	extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
	376	extern int iscsi_queuecommand(struct Scsi_Host host, struct scsi_cmnd sc);
	377
	378	/*
	379	* iSCSI host helpers.
	380	*/
	381	#define iscsi_host_priv(_shost) \
	382	(shost_priv(_shost) + sizeof(struct iscsi_host))
	383
	384	extern int iscsi_host_set_param(struct Scsi_Host *shost,
	385	enum iscsi_host_param param, char *buf,
	386	int buflen);
	387	extern int iscsi_host_get_param(struct Scsi_Host *shost,
	388	enum iscsi_host_param param, char *buf);
	389	extern int iscsi_host_add(struct Scsi_Host shost, struct device pdev);
	390	extern struct Scsi_Host iscsi_host_alloc(struct scsi_host_template sht,
	391	int dd_data_size,
	392	bool xmit_can_sleep);
	393	extern void iscsi_host_remove(struct Scsi_Host *shost);
	394	extern void iscsi_host_free(struct Scsi_Host *shost);
	395	extern int iscsi_target_alloc(struct scsi_target *starget);
	396
	397	/*
	398	* session management
	399	*/
	400	extern struct iscsi_cls_session *
	401	iscsi_session_setup(struct iscsi_transport , struct Scsi_Host shost,
	402	uint16_t, int, int, uint32_t, unsigned int);
	403	extern void iscsi_session_teardown(struct iscsi_cls_session *);
	404	extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
	405	extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
	406	enum iscsi_param param, char *buf, int buflen);
	407	extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
	408	enum iscsi_param param, char *buf);
	409
	410	#define iscsi_session_printk(prefix, _sess, fmt, a...) \
	411	iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
	412
	413	/*
	414	* connection management
	415	*/
	416	extern struct iscsi_cls_conn iscsi_conn_setup(struct iscsi_cls_session ,
	417	int, uint32_t);
	418	extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
	419	extern int iscsi_conn_start(struct iscsi_cls_conn *);
	420	extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
	421	extern int iscsi_conn_bind(struct iscsi_cls_session , struct iscsi_cls_conn ,
	422	int);
	423	extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
	424	extern void iscsi_session_failure(struct iscsi_session *session,
	425	enum iscsi_err err);
	426	extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
	427	enum iscsi_param param, char *buf);
	428	extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
	429	enum iscsi_param param, char *buf);
	430	extern void iscsi_suspend_tx(struct iscsi_conn *conn);
	431	extern void iscsi_suspend_queue(struct iscsi_conn *conn);
	432	extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
	433
	434	#define iscsi_conn_printk(prefix, _c, fmt, a...) \
	435	iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
	436	fmt, ##a)
	437
	438	/*
	439	* pdu and task processing
	440	*/
	441	extern void iscsi_update_cmdsn(struct iscsi_session , struct iscsi_nopin );
	442	extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
	443	struct iscsi_r2t_info *r2t,
	444	struct iscsi_data *hdr);
	445	extern int iscsi_conn_send_pdu(struct iscsi_cls_conn , struct iscsi_hdr ,
	446	char *, uint32_t);
	447	extern int iscsi_complete_pdu(struct iscsi_conn , struct iscsi_hdr ,
	448	char *, int);
	449	extern int __iscsi_complete_pdu(struct iscsi_conn , struct iscsi_hdr ,
	450	char *, int);
	451	extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
	452	extern struct iscsi_task iscsi_itt_to_ctask(struct iscsi_conn , itt_t);
	453	extern struct iscsi_task iscsi_itt_to_task(struct iscsi_conn , itt_t);
	454	extern void iscsi_requeue_task(struct iscsi_task *task);
	455	extern void iscsi_put_task(struct iscsi_task *task);
	456	extern void __iscsi_put_task(struct iscsi_task *task);
	457	extern void __iscsi_get_task(struct iscsi_task *task);
	458	extern void iscsi_complete_scsi_task(struct iscsi_task *task,
	459	uint32_t exp_cmdsn, uint32_t max_cmdsn);
	460
	461	/*
	462	* generic helpers
	463	*/
	464	extern void iscsi_pool_free(struct iscsi_pool *);
	465	extern int iscsi_pool_init(struct iscsi_pool , int, void **, int);
	466	extern int iscsi_switch_str_param(char *, char );
	467
	468	/*
	469	* inline functions to deal with padding.
	470	*/
	471	static inline unsigned int
	472	iscsi_padded(unsigned int len)
	473	{
	474	return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
	475	}
	476
	477	static inline unsigned int
	478	iscsi_padding(unsigned int len)
	479	{
	480	len &= (ISCSI_PAD_LEN - 1);
	481	if (len)
	482	len = ISCSI_PAD_LEN - len;
	483	return len;
	484	}
	485
	486	#endif