include/scsi/scsi_transport_iscsi.h

   1 /*
   2  * iSCSI transport class definitions
   3  *
   4  * Copyright (C) IBM Corporation, 2004
   5  * Copyright (C) Mike Christie, 2004 - 2005
   6  * Copyright (C) Dmitry Yusupov, 2004 - 2005
   7  * Copyright (C) Alex Aizman, 2004 - 2005
   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 SCSI_TRANSPORT_ISCSI_H
  24 #define SCSI_TRANSPORT_ISCSI_H
  25
  26 #include <linux/device.h>
  27 #include <scsi/iscsi_if.h>
  28
  29 struct scsi_transport_template;
  30 struct Scsi_Host;
  31 struct mempool_zone;
  32 struct iscsi_cls_conn;
  33
  34 /**
  35  * struct iscsi_transport - iSCSI Transport template
  36  *
  37  * @name:               transport name
  38  * @caps:               iSCSI Data-Path capabilities
  39  * @create_session:     create new iSCSI session object
  40  * @destroy_session:    destroy existing iSCSI session object
  41  * @create_conn:        create new iSCSI connection
  42  * @bind_conn:          associate this connection with existing iSCSI session
  43  *                      and specified transport descriptor
  44  * @destroy_conn:       destroy inactive iSCSI connection
  45  * @set_param:          set iSCSI Data-Path operational parameter
  46  * @start_conn:         set connection to be operational
  47  * @stop_conn:          suspend/recover/terminate connection
  48  * @send_pdu:           send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text.
  49  *
  50  * Template API provided by iSCSI Transport
  51  */
  52 struct iscsi_transport {
  53         struct module *owner;
  54         char *name;
  55         unsigned int caps;
  56         struct scsi_host_template *host_template;
  57         /* LLD session/scsi_host data size */
  58         int hostdata_size;
  59         /* LLD iscsi_host data size */
  60         int ihostdata_size;
  61         /* LLD connection data size */
  62         int conndata_size;
  63         int max_lun;
  64         unsigned int max_conn;
  65         unsigned int max_cmd_len;
  66         struct iscsi_cls_session *(*create_session)
  67                 (struct scsi_transport_template *t, uint32_t sn, uint32_t *sid);
  68         void (*destroy_session) (struct iscsi_cls_session *session);
  69         struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess,
  70                                 uint32_t cid);
  71         int (*bind_conn) (struct iscsi_cls_session *session,
  72                           struct iscsi_cls_conn *cls_conn,
  73                           uint32_t transport_fd, int is_leading);
  74         int (*start_conn) (struct iscsi_cls_conn *conn);
  75         void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
  76         void (*destroy_conn) (struct iscsi_cls_conn *conn);
  77         int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
  78                           uint32_t value);
  79         int (*get_conn_param) (struct iscsi_cls_conn *conn,
  80                                enum iscsi_param param,
  81                                uint32_t *value);
  82         int (*get_session_param) (struct iscsi_cls_session *session,
  83                                   enum iscsi_param param, uint32_t *value);
  84         int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
  85                          char *data, uint32_t data_size);
  86         void (*get_stats) (struct iscsi_cls_conn *conn,
  87                            struct iscsi_stats *stats);
  88 };
  89
  90 /*
  91  * transport registration upcalls
  92  */
  93 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
  94 extern int iscsi_unregister_transport(struct iscsi_transport *tt);
  95
  96 /*
  97  * control plane upcalls
  98  */
  99 extern void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error);
 100 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 101                           char *data, uint32_t data_size);
 102
 103 struct iscsi_cls_conn {
 104         struct list_head conn_list;     /* item in connlist */
 105         void *dd_data;                  /* LLD private data */
 106         struct iscsi_transport *transport;
 107         int active;                     /* must be accessed with the connlock */
 108         struct device dev;              /* sysfs transport/container device */
 109         struct mempool_zone *z_error;
 110         struct mempool_zone *z_pdu;
 111         struct list_head freequeue;
 112 };
 113
 114 #define iscsi_dev_to_conn(_dev) \
 115         container_of(_dev, struct iscsi_cls_conn, dev)
 116
 117 struct iscsi_cls_session {
 118         struct list_head sess_list;             /* item in session_list */
 119         struct iscsi_transport *transport;
 120         struct device dev;      /* sysfs transport/container device */
 121 };
 122
 123 #define iscsi_dev_to_session(_dev) \
 124         container_of(_dev, struct iscsi_cls_session, dev)
 125
 126 #define iscsi_session_to_shost(_session) \
 127         dev_to_shost(_session->dev.parent)
 128
 129 /*
 130  * session and connection functions that can be used by HW iSCSI LLDs
 131  */
 132 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
 133                                 struct iscsi_transport *t);
 134 extern int iscsi_destroy_session(struct iscsi_cls_session *session);
 135 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
 136                                             uint32_t cid);
 137 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
 138
 139 /*
 140  * session functions used by software iscsi
 141  */
 142 extern struct Scsi_Host *
 143 iscsi_transport_create_session(struct scsi_transport_template *scsit,
 144                                struct iscsi_transport *transport);
 145 extern int iscsi_transport_destroy_session(struct Scsi_Host *shost);
 146
 147 #endif