/*
* iSCSI transport class definitions
*
* Copyright (C) IBM Corporation, 2004
* Copyright (C) Mike Christie, 2004 - 2006
* Copyright (C) Dmitry Yusupov, 2004 - 2005
* Copyright (C) Alex Aizman, 2004 - 2005
*
* 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 SCSI_TRANSPORT_ISCSI_H
#define SCSI_TRANSPORT_ISCSI_H
#include <linux/device.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <scsi/iscsi_if.h>
struct scsi_transport_template;
struct iscsi_transport;
struct Scsi_Host;
struct iscsi_cls_conn;
struct iscsi_conn;
struct iscsi_cmd_task;
struct sockaddr;
/**
* struct iscsi_transport - iSCSI Transport template
*
* @name: transport name
* @caps: iSCSI Data-Path capabilities
* @create_session: create new iSCSI session object
* @destroy_session: destroy existing iSCSI session object
* @create_conn: create new iSCSI connection
* @bind_conn: associate this connection with existing iSCSI session
* and specified transport descriptor
* @destroy_conn: destroy inactive iSCSI connection
* @set_param: set iSCSI parameter. Return 0 on success, -ENODATA
* when param is not supported, and a -Exx value on other
* error.
* @get_param get iSCSI parameter. Must return number of bytes
* copied to buffer on success, -ENODATA when param
* is not supported, and a -Exx value on other error
* @start_conn: set connection to be operational
* @stop_conn: suspend/recover/terminate connection
* @send_pdu: send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text.
* @session_recovery_timedout: notify LLD a block during recovery timed out
* @init_task: Initialize a iscsi_task and any internal structs.
* When offloading the data path, this is called from
* queuecommand with the session lock, or from the
* iscsi_conn_send_pdu context with the session lock.
* When not offloading the data path, this is called
* from the scsi work queue without the session lock.
* @xmit_task Requests LLD to transfer cmd task. Returns 0 or the
* the number of bytes transferred on success, and -Exyz
* value on error. When offloading the data path, this
* is called from queuecommand with the session lock, or
* from the iscsi_conn_send_pdu context with the session
* lock. When not offloading the data path, this is called
* from the scsi work queue without the session lock.
* @cleanup_task: requests LLD to fail task. Called with session lock
* and after the connection has been suspended and
* terminated during recovery. If called
* from abort task then connection is not suspended
* or terminated but sk_callback_lock is held
*
* Template API provided by iSCSI Transport
*/
struct iscsi_transport {
struct module *owner;
char *name;
unsigned int caps;
/* LLD sets this to indicate what values it can export to sysfs */
uint64_t param_mask;
uint64_t host_param_mask;
struct iscsi_cls_session *(*create_session) (struct Scsi_Host *shost,
uint16_t cmds_max, uint16_t qdepth,
uint32_t sn, uint32_t *hn);
void (*destroy_session) (struct iscsi_cls_session *session);
struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess,
uint32_t cid);
int (*bind_conn) (struct iscsi_cls_session *session,
struct iscsi_cls_conn *cls_conn,
uint64_t transport_eph, int is_leading);
int (*start_conn) (struct iscsi_cls_conn *conn);
void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
void (*destroy_conn) (struct iscsi_cls_conn *conn);
int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
char *buf, int buflen);
int (*get_conn_param) (struct iscsi_cls_conn *conn,
enum iscsi_param param, char *buf);
int (*get_session_param) (struct iscsi_cls_session *session,
enum iscsi_param param, char *buf);
int (*get_host_param) (struct Scsi_Host *shost,
enum iscsi_host_param param, char *buf);
int (*set_host_param) (struct Scsi_Host *shost,
enum iscsi_host_param param, char *buf,
int buflen);
int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
char *data, uint32_t data_size);
void (*get_stats) (struct iscsi_cls_conn *conn,
struct iscsi_stats *stats);
int (*init_task) (struct iscsi_cmd_task *task);
int (*xmit_task) (struct iscsi_cmd_task *task);
void (*cleanup_task) (struct iscsi_conn *conn,
struct iscsi_cmd_task *task);
void (*session_recovery_timedout) (struct iscsi_cls_session *session);
int (*ep_connect) (struct sockaddr *dst_addr, int non_blocking,
uint64_t *ep_handle);
int (*ep_poll) (uint64_t ep_handle, int timeout_ms);
void (*ep_disconnect) (uint64_t ep_handle);
int (*tgt_dscvr) (struct Scsi_Host *shost, enum iscsi_tgt_dscvr type,
uint32_t enable, struct sockaddr *dst_addr);
};
/*
* transport registration upcalls
*/
extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
extern int iscsi_unregister_transport(struct iscsi_transport *tt);
/*
* control plane upcalls
*/
extern void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error);
extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
char *data, uint32_t data_size);
struct iscsi_cls_conn {
struct list_head conn_list; /* item in connlist */
void *dd_data; /* LLD private data */
struct iscsi_transport *transport;
uint32_t cid; /* connection id */
int active; /* must be accessed with the connlock */
struct device dev; /* sysfs transport/container device */
};
#define iscsi_dev_to_conn(_dev) \
container_of(_dev, struct iscsi_cls_conn, dev)
#define iscsi_conn_to_session(_conn) \
iscsi_dev_to_session(_conn->dev.parent)
/* iscsi class session state */
enum {
ISCSI_SESSION_LOGGED_IN,
ISCSI_SESSION_FAILED,
ISCSI_SESSION_FREE,
};
struct iscsi_cls_session {
struct list_head sess_list; /* item in session_list */
struct list_head host_list;
struct iscsi_transport *transport;
spinlock_t lock;
struct work_struct block_work;
struct work_struct unblock_work;
struct work_struct scan_work;
struct work_struct unbind_work;
/* recovery fields */
int recovery_tmo;
struct delayed_work recovery_work;
int target_id;
int state;
int sid; /* session id */
void *dd_data; /* LLD private data */
struct device dev; /* sysfs transport/container device */
};
#define iscsi_dev_to_session(_dev) \
container_of(_dev, struct iscsi_cls_session, dev)
#define iscsi_session_to_shost(_session) \
dev_to_shost(_session->dev.parent)
#define starget_to_session(_stgt) \
iscsi_dev_to_session(_stgt->dev.parent)
struct iscsi_cls_host {
struct list_head sessions;
atomic_t nr_scans;
struct mutex mutex;
struct workqueue_struct *scan_workq;
char scan_workq_name[KOBJ_NAME_LEN];
};
extern void iscsi_host_for_each_session(struct Scsi_Host *shost,
void (*fn)(struct iscsi_cls_session *));
/*
* session and connection functions that can be used by HW iSCSI LLDs
*/
#define iscsi_cls_session_printk(prefix, _cls_session, fmt, a...) \
dev_printk(prefix, &(_cls_session)->dev, fmt, ##a)
#define iscsi_cls_conn_printk(prefix, _cls_conn, fmt, a...) \
dev_printk(prefix, &(_cls_conn)->dev, fmt, ##a)
extern int iscsi_session_chkready(struct iscsi_cls_session *session);
extern struct iscsi_cls_session *iscsi_alloc_session(struct Scsi_Host *shost,
struct iscsi_transport *transport, int dd_size);
extern int iscsi_add_session(struct iscsi_cls_session *session,
unsigned int target_id);
extern int iscsi_session_event(struct iscsi_cls_session *session,
enum iscsi_uevent_e event);
extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
struct iscsi_transport *t,
int dd_size,
unsigned int target_id);
extern void iscsi_remove_session(struct iscsi_cls_session *session);
extern void iscsi_free_session(struct iscsi_cls_session *session);
extern int iscsi_destroy_session(struct iscsi_cls_session *session);
extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
int dd_size, uint32_t cid);
extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
extern void iscsi_unblock_session(struct iscsi_cls_session *session);
extern void iscsi_block_session(struct iscsi_cls_session *session);
extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time);
#endif
