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linux/include/scsi/libiscsi.h

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/*
* 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/mutex.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <scsi/iscsi_proto.h>
#include <scsi/iscsi_if.h>
struct scsi_transport_template;
struct scsi_device;
struct Scsi_Host;
struct scsi_cmnd;
struct socket;
struct iscsi_transport;
struct iscsi_cls_session;
struct iscsi_cls_conn;
struct iscsi_session;
struct iscsi_nopin;
/* #define DEBUG_SCSI */
#ifdef DEBUG_SCSI
#define debug_scsi(fmt...) printk(KERN_INFO "iscsi: " fmt)
#else
#define debug_scsi(fmt...)
#endif
#define ISCSI_XMIT_CMDS_MAX 128 /* must be power of 2 */
#define ISCSI_MGMT_CMDS_MAX 32 /* must be power of 2 */
#define ISCSI_CONN_MAX 1
#define ISCSI_MGMT_ITT_OFFSET 0xa00
#define ISCSI_DEF_CMD_PER_LUN 32
#define ISCSI_MAX_CMD_PER_LUN 128
/* Task Mgmt states */
#define TMABORT_INITIAL 0x0
#define TMABORT_SUCCESS 0x1
#define TMABORT_FAILED 0x2
#define TMABORT_TIMEDOUT 0x3
#define TMABORT_NOT_FOUND 0x4
/* Connection suspend "bit" */
#define ISCSI_SUSPEND_BIT 1
#define ISCSI_ITT_MASK (0xfff)
#define ISCSI_CID_SHIFT 12
#define ISCSI_CID_MASK (0xffff << ISCSI_CID_SHIFT)
#define ISCSI_AGE_SHIFT 28
#define ISCSI_AGE_MASK (0xf << ISCSI_AGE_SHIFT)
struct iscsi_mgmt_task {
/*
* Becuae LLDs allocate their hdr differently, this is a pointer to
* that storage. It must be setup at session creation time.
*/
struct iscsi_hdr *hdr;
char *data; /* mgmt payload */
int data_count; /* counts data to be sent */
uint32_t itt; /* this ITT */
void *dd_data; /* driver/transport data */
struct list_head running;
};
enum {
ISCSI_TASK_COMPLETED,
ISCSI_TASK_PENDING,
ISCSI_TASK_RUNNING,
};
struct iscsi_cmd_task {
/*
* Becuae LLDs allocate their hdr differently, this is a pointer to
* that storage. It must be setup at session creation time.
*/
struct iscsi_cmd *hdr;
int itt; /* this ITT */
int datasn; /* DataSN */
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;
struct iscsi_conn *conn; /* used connection */
struct iscsi_mgmt_task *mtask; /* tmf mtask in progr */
/* state set/tested under session->lock */
int state;
atomic_t refcount;
struct list_head running; /* running cmd list */
void *dd_data; /* driver/transport data */
};
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 */
/*
* LLDs should set this lock. It protects the transport recv
* code
*/
rwlock_t *recv_lock;
/*
* conn_stop() flag: stop to recover, stop to terminate
*/
int stop_stage;
/* iSCSI connection-wide sequencing */
uint32_t exp_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_mgmt_task *login_mtask; /* mtask used for login/text */
struct iscsi_mgmt_task *mtask; /* xmit mtask in progress */
struct iscsi_cmd_task *ctask; /* xmit ctask in progress */
/* xmit */
struct kfifo *immqueue; /* immediate xmit queue */
struct kfifo *mgmtqueue; /* mgmt (control) xmit queue */
struct list_head mgmt_run_list; /* list of control tasks */
struct list_head xmitqueue; /* data-path cmd queue */
struct list_head run_list; /* list of cmds in progress */
struct work_struct xmitwork; /* per-conn. xmit workqueue */
/*
* serializes connection xmit, access to kfifos:
* xmitqueue, immqueue, mgmtqueue
*/
struct mutex xmitmutex;
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 tmabort_timer;
int tmabort_state; /* see TMABORT_INITIAL, etc.*/
/* negotiated params */
int max_recv_dlength; /* initiator_max_recv_dsl*/
int 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;
/* 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;
};
struct iscsi_queue {
struct kfifo *queue; /* FIFO Queue */
void **pool; /* Pool of elements */
int max; /* Max number of elements */
};
struct iscsi_session {
/* iSCSI session-wide sequencing */
uint32_t cmdsn;
uint32_t exp_cmdsn;
uint32_t max_cmdsn;
/* configuration */
int initial_r2t_en;
int max_r2t;
int imm_data_en;
int first_burst;
int max_burst;
int time2wait;
int time2retain;
int pdu_inorder_en;
int dataseq_inorder_en;
int erl;
int tpgt;
char *targetname;
/* 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 cmds_max; /* size of cmds array */
struct iscsi_cmd_task **cmds; /* Original Cmds arr */
struct iscsi_queue cmdpool; /* PDU's pool */
int mgmtpool_max; /* size of mgmt array */
struct iscsi_mgmt_task **mgmt_cmds; /* Original mgmt arr */
struct iscsi_queue mgmtpool; /* Mgmt PDU's pool */
};
/*
* scsi host template
*/
extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
extern int iscsi_eh_abort(struct scsi_cmnd *sc);
extern int iscsi_eh_host_reset(struct scsi_cmnd *sc);
extern int iscsi_queuecommand(struct scsi_cmnd *sc,
void (*done)(struct scsi_cmnd *));
/*
* session management
*/
extern struct iscsi_cls_session *
iscsi_session_setup(struct iscsi_transport *, struct scsi_transport_template *,
int, int, uint32_t, uint32_t *);
extern void iscsi_session_teardown(struct iscsi_cls_session *);
extern struct iscsi_session *class_to_transport_session(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 session_to_cls(_sess) \
hostdata_session(_sess->host->hostdata)
/*
* connection management
*/
extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
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 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
enum iscsi_param param, char *buf);
/*
* pdu and task processing
*/
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);
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 *, struct iscsi_hdr *,
uint32_t *);
/*
* generic helpers
*/
extern void iscsi_pool_free(struct iscsi_queue *, void **);
extern int iscsi_pool_init(struct iscsi_queue *, int, void ***, int);
#endif