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         /* LLD sets this to indicate what values it can export to sysfs */
  57         unsigned int param_mask;
  58         struct scsi_host_template *host_template;
  59         /* LLD session/scsi_host data size */
  60         int hostdata_size;
  61         /* LLD connection data size */
  62         int conndata_size;
  63         /* LLD session data size */
  64         int sessiondata_size;
  65         int max_lun;
  66         unsigned int max_conn;
  67         unsigned int max_cmd_len;
  68         struct iscsi_cls_session *(*create_session)
  69                 (struct scsi_transport_template *t, uint32_t sn, uint32_t *hn);
  70         void (*destroy_session) (struct iscsi_cls_session *session);
  71         struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess,
  72                                 uint32_t cid);
  73         int (*bind_conn) (struct iscsi_cls_session *session,
  74                           struct iscsi_cls_conn *cls_conn,
  75                           uint32_t transport_fd, int is_leading);
  76         int (*start_conn) (struct iscsi_cls_conn *conn);
  77         void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
  78         void (*destroy_conn) (struct iscsi_cls_conn *conn);
  79         int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
  80                           uint32_t value);
  81         int (*get_conn_param) (struct iscsi_cls_conn *conn,
  82                                enum iscsi_param param, uint32_t *value);
  83         int (*get_session_param) (struct iscsi_cls_session *session,
  84                                   enum iscsi_param param, uint32_t *value);
  85         int (*get_conn_str_param) (struct iscsi_cls_conn *conn,
  86                                    enum iscsi_param param, char *buf);
  87         int (*get_session_str_param) (struct iscsi_cls_session *session,
  88                                       enum iscsi_param param, char *buf);
  89         int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
  90                          char *data, uint32_t data_size);
  91         void (*get_stats) (struct iscsi_cls_conn *conn,
  92                            struct iscsi_stats *stats);
  93 };
  94
  95 /*
  96  * transport registration upcalls
  97  */
  98 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
  99 extern int iscsi_unregister_transport(struct iscsi_transport *tt);
 100
 101 /*
 102  * control plane upcalls
 103  */
 104 extern void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error);
 105 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 106                           char *data, uint32_t data_size);
 107
 108 struct iscsi_cls_conn {
 109         struct list_head conn_list;     /* item in connlist */
 110         void *dd_data;                  /* LLD private data */
 111         struct iscsi_transport *transport;
 112         uint32_t cid;                   /* connection id */
 113
 114         /* portal/group values we got during discovery */
 115         char *persistent_address;
 116         int persistent_port;
 117         /* portal/group values we are currently using */
 118         char *address;
 119         int port;
 120
 121         int active;                     /* must be accessed with the connlock */
 122         struct device dev;              /* sysfs transport/container device */
 123         struct mempool_zone *z_error;
 124         struct mempool_zone *z_pdu;
 125         struct list_head freequeue;
 126 };
 127
 128 #define iscsi_dev_to_conn(_dev) \
 129         container_of(_dev, struct iscsi_cls_conn, dev)
 130
 131 struct iscsi_cls_session {
 132         struct list_head sess_list;             /* item in session_list */
 133         struct iscsi_transport *transport;
 134
 135         /* iSCSI values used as unique id by userspace. */
 136         char *targetname;
 137         int tpgt;
 138
 139         int sid;                                /* session id */
 140         void *dd_data;                          /* LLD private data */
 141         struct device dev;      /* sysfs transport/container device */
 142 };
 143
 144 #define iscsi_dev_to_session(_dev) \
 145         container_of(_dev, struct iscsi_cls_session, dev)
 146
 147 #define iscsi_session_to_shost(_session) \
 148         dev_to_shost(_session->dev.parent)
 149
 150 /*
 151  * session and connection functions that can be used by HW iSCSI LLDs
 152  */
 153 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
 154                                 struct iscsi_transport *t);
 155 extern int iscsi_destroy_session(struct iscsi_cls_session *session);
 156 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
 157                                             uint32_t cid);
 158 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
 159
 160 /*
 161  * session functions used by software iscsi
 162  */
 163 extern struct Scsi_Host *
 164 iscsi_transport_create_session(struct scsi_transport_template *scsit,
 165                                struct iscsi_transport *transport);
 166 extern int iscsi_transport_destroy_session(struct Scsi_Host *shost);
 167
 168 #endif