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 Scsi_Host *(*create_session) (struct scsi_transport_template *t,
  67                                              uint32_t initial_cmdsn);
  68         void (*destroy_session) (struct Scsi_Host *shost);
  69         struct iscsi_cls_conn *(*create_conn) (struct Scsi_Host *shost,
  70                                 uint32_t cid);
  71         int (*bind_conn) (iscsi_sessionh_t session, iscsi_connh_t conn,
  72                           uint32_t transport_fd, int is_leading);
  73         int (*start_conn) (iscsi_connh_t conn);
  74         void (*stop_conn) (iscsi_connh_t conn, int flag);
  75         void (*destroy_conn) (struct iscsi_cls_conn *conn);
  76         int (*set_param) (iscsi_connh_t conn, enum iscsi_param param,
  77                           uint32_t value);
  78         int (*get_conn_param) (void *conndata, enum iscsi_param param,
  79                                uint32_t *value);
  80         int (*get_session_param) (struct Scsi_Host *shost,
  81                                   enum iscsi_param param, uint32_t *value);
  82         int (*send_pdu) (iscsi_connh_t conn, struct iscsi_hdr *hdr,
  83                          char *data, uint32_t data_size);
  84         void (*get_stats) (iscsi_connh_t conn, struct iscsi_stats *stats);
  85 };
  86
  87 /*
  88  * transport registration upcalls
  89  */
  90 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
  91 extern int iscsi_unregister_transport(struct iscsi_transport *tt);
  92
  93 /*
  94  * control plane upcalls
  95  */
  96 extern void iscsi_conn_error(iscsi_connh_t conn, enum iscsi_err error);
  97 extern int iscsi_recv_pdu(iscsi_connh_t conn, struct iscsi_hdr *hdr,
  98                           char *data, uint32_t data_size);
  99
 100 struct iscsi_cls_conn {
 101         struct list_head conn_list;     /* item in connlist */
 102         void *dd_data;                  /* LLD private data */
 103         struct iscsi_transport *transport;
 104         iscsi_connh_t connh;
 105         int active;                     /* must be accessed with the connlock */
 106         struct device dev;              /* sysfs transport/container device */
 107         struct mempool_zone *z_error;
 108         struct mempool_zone *z_pdu;
 109         struct list_head freequeue;
 110 };
 111
 112 #define iscsi_dev_to_conn(_dev) \
 113         container_of(_dev, struct iscsi_cls_conn, dev)
 114
 115 struct iscsi_cls_session {
 116         struct list_head list;  /* item in session_list */
 117         struct iscsi_transport *transport;
 118         struct device dev;      /* sysfs transport/container device */
 119 };
 120
 121 #define iscsi_dev_to_session(_dev) \
 122         container_of(_dev, struct iscsi_cls_session, dev)
 123
 124 #define iscsi_session_to_shost(_session) \
 125         dev_to_shost(_session->dev.parent)
 126
 127 /*
 128  * session and connection functions that can be used by HW iSCSI LLDs
 129  */
 130 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
 131                                 struct iscsi_transport *t);
 132 extern int iscsi_destroy_session(struct iscsi_cls_session *session);
 133 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
 134                                             uint32_t cid);
 135 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
 136
 137 /*
 138  * session functions used by software iscsi
 139  */
 140 extern struct Scsi_Host *
 141 iscsi_transport_create_session(struct scsi_transport_template *scsit,
 142                                struct iscsi_transport *transport);
 143 extern int iscsi_transport_destroy_session(struct Scsi_Host *shost);
 144
 145 #endif