scsi_transport_iscsi.h

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/*
 * 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 iscsi_endpoint;
struct Scsi_Host;
struct scsi_cmnd;
struct iscsi_cls_conn;
struct iscsi_conn;
struct iscsi_task;
struct sockaddr;
struct iscsi_iface;
struct bsg_job;

struct iscsi_transport {
    struct module *owner;
    char *name;
    unsigned int caps;

    struct iscsi_cls_session *(*create_session) (struct iscsi_endpoint *ep,
                    uint16_t cmds_max, uint16_t qdepth,
                    uint32_t sn);
    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_ep_param) (struct iscsi_endpoint *ep, enum iscsi_param param,
                 char *buf);
    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_task *task);
    int (*xmit_task) (struct iscsi_task *task);
    void (*cleanup_task) (struct iscsi_task *task);

    int (*alloc_pdu) (struct iscsi_task *task, uint8_t opcode);
    int (*xmit_pdu) (struct iscsi_task *task);
    int (*init_pdu) (struct iscsi_task *task, unsigned int offset,
             unsigned int count);
    void (*parse_pdu_itt) (struct iscsi_conn *conn, itt_t itt,
                   int *index, int *age);

    void (*session_recovery_timedout) (struct iscsi_cls_session *session);
    struct iscsi_endpoint *(*ep_connect) (struct Scsi_Host *shost,
                          struct sockaddr *dst_addr,
                          int non_blocking);
    int (*ep_poll) (struct iscsi_endpoint *ep, int timeout_ms);
    void (*ep_disconnect) (struct iscsi_endpoint *ep);
    int (*tgt_dscvr) (struct Scsi_Host *shost, enum iscsi_tgt_dscvr type,
              uint32_t enable, struct sockaddr *dst_addr);
    int (*set_path) (struct Scsi_Host *shost, struct iscsi_path *params);
    int (*set_iface_param) (struct Scsi_Host *shost, void *data,
                uint32_t len);
    int (*get_iface_param) (struct iscsi_iface *iface,
                enum iscsi_param_type param_type,
                int param, char *buf);
    umode_t (*attr_is_visible)(int param_type, int param);
    int (*bsg_request)(struct bsg_job *job);
    int (*send_ping) (struct Scsi_Host *shost, uint32_t iface_num,
              uint32_t iface_type, uint32_t payload_size,
              uint32_t pid, struct sockaddr *dst_addr);
    int (*get_chap) (struct Scsi_Host *shost, uint16_t chap_tbl_idx,
             uint32_t *num_entries, char *buf);
    int (*delete_chap) (struct Scsi_Host *shost, uint16_t chap_tbl_idx);
};

/*
 * 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_event(struct iscsi_cls_conn *conn,
                   enum iscsi_err error);
extern void iscsi_conn_login_event(struct iscsi_cls_conn *conn,
                   enum iscsi_conn_state state);
extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
              char *data, uint32_t data_size);

extern int iscsi_offload_mesg(struct Scsi_Host *shost,
                  struct iscsi_transport *transport, uint32_t type,
                  char *data, uint16_t data_size);

extern void iscsi_post_host_event(uint32_t host_no,
                  struct iscsi_transport *transport,
                  enum iscsi_host_event_code code,
                  uint32_t data_size,
                  uint8_t *data);

extern void iscsi_ping_comp_event(uint32_t host_no,
                  struct iscsi_transport *transport,
                  uint32_t status, uint32_t pid,
                  uint32_t data_size, uint8_t *data);

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 */
    struct mutex ep_mutex;
    struct iscsi_endpoint *ep;

    struct device dev;      /* sysfs transport/container device */
};

#define iscsi_dev_to_conn(_dev) \
    container_of(_dev, struct iscsi_cls_conn, dev)

#define transport_class_to_conn(_cdev) \
    iscsi_dev_to_conn(_cdev->parent)

#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,
};

#define ISCSI_MAX_TARGET -1

struct iscsi_cls_session {
    struct list_head sess_list;     /* item in session_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;

    unsigned int target_id;
    bool ida_used;

    /*
     * pid of userspace process that created session or -1 if
     * created by the kernel.
     */
    pid_t creator;
    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 transport_class_to_session(_cdev) \
    iscsi_dev_to_session(_cdev->parent)

#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 {
    atomic_t nr_scans;
    struct mutex mutex;
    struct request_queue *bsg_q;
    uint32_t port_speed;
    uint32_t port_state;
};

#define iscsi_job_to_shost(_job) \
        dev_to_shost(_job->dev)

extern void iscsi_host_for_each_session(struct Scsi_Host *shost,
                void (*fn)(struct iscsi_cls_session *));

struct iscsi_endpoint {
    void *dd_data;          /* LLD private data */
    struct device dev;
    uint64_t id;
    struct iscsi_cls_conn *conn;
};

struct iscsi_iface {
    struct device dev;
    struct iscsi_transport *transport;
    uint32_t iface_type;    /* IPv4 or IPv6 */
    uint32_t iface_num; /* iface number, 0 - n */
    void *dd_data;      /* LLD private data */
};

#define iscsi_dev_to_iface(_dev) \
    container_of(_dev, struct iscsi_iface, dev)

#define iscsi_iface_to_shost(_iface) \
    dev_to_shost(_iface->dev.parent)

/*
 * 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 int iscsi_is_session_online(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);
extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size);
extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep);
extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle);
extern int iscsi_block_scsi_eh(struct scsi_cmnd *cmd);
extern struct iscsi_iface *iscsi_create_iface(struct Scsi_Host *shost,
                          struct iscsi_transport *t,
                          uint32_t iface_type,
                          uint32_t iface_num, int dd_size);
extern void iscsi_destroy_iface(struct iscsi_iface *iface);
extern struct iscsi_iface *iscsi_lookup_iface(int handle);
extern char *iscsi_get_port_speed_name(struct Scsi_Host *shost);
extern char *iscsi_get_port_state_name(struct Scsi_Host *shost);
extern int iscsi_is_session_dev(const struct device *dev);

#endif