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 - 2006
   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 <linux/list.h>
  28 #include <linux/mutex.h>
  29 #include <scsi/iscsi_if.h>
  30
  31 struct scsi_transport_template;
  32 struct iscsi_transport;
  33 struct iscsi_endpoint;
  34 struct Scsi_Host;
  35 struct scsi_cmnd;
  36 struct iscsi_cls_conn;
  37 struct iscsi_conn;
  38 struct iscsi_task;
  39 struct sockaddr;
  40 struct iscsi_iface;
  41 struct bsg_job;
  42
  43 /**
  44  * struct iscsi_transport - iSCSI Transport template
  45  *
  46  * @name:               transport name
  47  * @caps:               iSCSI Data-Path capabilities
  48  * @create_session:     create new iSCSI session object
  49  * @destroy_session:    destroy existing iSCSI session object
  50  * @create_conn:        create new iSCSI connection
  51  * @bind_conn:          associate this connection with existing iSCSI session
  52  *                      and specified transport descriptor
  53  * @destroy_conn:       destroy inactive iSCSI connection
  54  * @set_param:          set iSCSI parameter. Return 0 on success, -ENODATA
  55  *                      when param is not supported, and a -Exx value on other
  56  *                      error.
  57  * @get_param           get iSCSI parameter. Must return number of bytes
  58  *                      copied to buffer on success, -ENODATA when param
  59  *                      is not supported, and a -Exx value on other error
  60  * @start_conn:         set connection to be operational
  61  * @stop_conn:          suspend/recover/terminate connection
  62  * @send_pdu:           send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text.
  63  * @session_recovery_timedout: notify LLD a block during recovery timed out
  64  * @init_task:          Initialize a iscsi_task and any internal structs.
  65  *                      When offloading the data path, this is called from
  66  *                      queuecommand with the session lock, or from the
  67  *                      iscsi_conn_send_pdu context with the session lock.
  68  *                      When not offloading the data path, this is called
  69  *                      from the scsi work queue without the session lock.
  70  * @xmit_task           Requests LLD to transfer cmd task. Returns 0 or the
  71  *                      the number of bytes transferred on success, and -Exyz
  72  *                      value on error. When offloading the data path, this
  73  *                      is called from queuecommand with the session lock, or
  74  *                      from the iscsi_conn_send_pdu context with the session
  75  *                      lock. When not offloading the data path, this is called
  76  *                      from the scsi work queue without the session lock.
  77  * @cleanup_task:       requests LLD to fail task. Called with session lock
  78  *                      and after the connection has been suspended and
  79  *                      terminated during recovery. If called
  80  *                      from abort task then connection is not suspended
  81  *                      or terminated but sk_callback_lock is held
  82  *
  83  * Template API provided by iSCSI Transport
  84  */
  85 struct iscsi_transport {
  86         struct module *owner;
  87         char *name;
  88         unsigned int caps;
  89
  90         struct iscsi_cls_session *(*create_session) (struct iscsi_endpoint *ep,
  91                                         uint16_t cmds_max, uint16_t qdepth,
  92                                         uint32_t sn);
  93         void (*destroy_session) (struct iscsi_cls_session *session);
  94         struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess,
  95                                 uint32_t cid);
  96         int (*bind_conn) (struct iscsi_cls_session *session,
  97                           struct iscsi_cls_conn *cls_conn,
  98                           uint64_t transport_eph, int is_leading);
  99         int (*start_conn) (struct iscsi_cls_conn *conn);
 100         void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
 101         void (*destroy_conn) (struct iscsi_cls_conn *conn);
 102         int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
 103                           char *buf, int buflen);
 104         int (*get_ep_param) (struct iscsi_endpoint *ep, enum iscsi_param param,
 105                              char *buf);
 106         int (*get_conn_param) (struct iscsi_cls_conn *conn,
 107                                enum iscsi_param param, char *buf);
 108         int (*get_session_param) (struct iscsi_cls_session *session,
 109                                   enum iscsi_param param, char *buf);
 110         int (*get_host_param) (struct Scsi_Host *shost,
 111                                 enum iscsi_host_param param, char *buf);
 112         int (*set_host_param) (struct Scsi_Host *shost,
 113                                enum iscsi_host_param param, char *buf,
 114                                int buflen);
 115         int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 116                          char *data, uint32_t data_size);
 117         void (*get_stats) (struct iscsi_cls_conn *conn,
 118                            struct iscsi_stats *stats);
 119
 120         int (*init_task) (struct iscsi_task *task);
 121         int (*xmit_task) (struct iscsi_task *task);
 122         void (*cleanup_task) (struct iscsi_task *task);
 123
 124         int (*alloc_pdu) (struct iscsi_task *task, uint8_t opcode);
 125         int (*xmit_pdu) (struct iscsi_task *task);
 126         int (*init_pdu) (struct iscsi_task *task, unsigned int offset,
 127                          unsigned int count);
 128         void (*parse_pdu_itt) (struct iscsi_conn *conn, itt_t itt,
 129                                int *index, int *age);
 130
 131         void (*session_recovery_timedout) (struct iscsi_cls_session *session);
 132         struct iscsi_endpoint *(*ep_connect) (struct Scsi_Host *shost,
 133                                               struct sockaddr *dst_addr,
 134                                               int non_blocking);
 135         int (*ep_poll) (struct iscsi_endpoint *ep, int timeout_ms);
 136         void (*ep_disconnect) (struct iscsi_endpoint *ep);
 137         int (*tgt_dscvr) (struct Scsi_Host *shost, enum iscsi_tgt_dscvr type,
 138                           uint32_t enable, struct sockaddr *dst_addr);
 139         int (*set_path) (struct Scsi_Host *shost, struct iscsi_path *params);
 140         int (*set_iface_param) (struct Scsi_Host *shost, void *data,
 141                                 uint32_t len);
 142         int (*get_iface_param) (struct iscsi_iface *iface,
 143                                 enum iscsi_param_type param_type,
 144                                 int param, char *buf);
 145         umode_t (*attr_is_visible)(int param_type, int param);
 146         int (*bsg_request)(struct bsg_job *job);
 147         int (*send_ping) (struct Scsi_Host *shost, uint32_t iface_num,
 148                           uint32_t iface_type, uint32_t payload_size,
 149                           uint32_t pid, struct sockaddr *dst_addr);
 150         int (*get_chap) (struct Scsi_Host *shost, uint16_t chap_tbl_idx,
 151                          uint32_t *num_entries, char *buf);
 152         int (*delete_chap) (struct Scsi_Host *shost, uint16_t chap_tbl_idx);
 153 };
 154
 155 /*
 156  * transport registration upcalls
 157  */
 158 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
 159 extern int iscsi_unregister_transport(struct iscsi_transport *tt);
 160
 161 /*
 162  * control plane upcalls
 163  */
 164 extern void iscsi_conn_error_event(struct iscsi_cls_conn *conn,
 165                                    enum iscsi_err error);
 166 extern void iscsi_conn_login_event(struct iscsi_cls_conn *conn,
 167                                    enum iscsi_conn_state state);
 168 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 169                           char *data, uint32_t data_size);
 170
 171 extern int iscsi_offload_mesg(struct Scsi_Host *shost,
 172                               struct iscsi_transport *transport, uint32_t type,
 173                               char *data, uint16_t data_size);
 174
 175 extern void iscsi_post_host_event(uint32_t host_no,
 176                                   struct iscsi_transport *transport,
 177                                   enum iscsi_host_event_code code,
 178                                   uint32_t data_size,
 179                                   uint8_t *data);
 180
 181 extern void iscsi_ping_comp_event(uint32_t host_no,
 182                                   struct iscsi_transport *transport,
 183                                   uint32_t status, uint32_t pid,
 184                                   uint32_t data_size, uint8_t *data);
 185
 186 struct iscsi_cls_conn {
 187         struct list_head conn_list;     /* item in connlist */
 188         void *dd_data;                  /* LLD private data */
 189         struct iscsi_transport *transport;
 190         uint32_t cid;                   /* connection id */
 191         struct mutex ep_mutex;
 192         struct iscsi_endpoint *ep;
 193
 194         struct device dev;              /* sysfs transport/container device */
 195 };
 196
 197 #define iscsi_dev_to_conn(_dev) \
 198         container_of(_dev, struct iscsi_cls_conn, dev)
 199
 200 #define transport_class_to_conn(_cdev) \
 201         iscsi_dev_to_conn(_cdev->parent)
 202
 203 #define iscsi_conn_to_session(_conn) \
 204         iscsi_dev_to_session(_conn->dev.parent)
 205
 206 /* iscsi class session state */
 207 enum {
 208         ISCSI_SESSION_LOGGED_IN,
 209         ISCSI_SESSION_FAILED,
 210         ISCSI_SESSION_FREE,
 211 };
 212
 213 #define ISCSI_MAX_TARGET -1
 214
 215 struct iscsi_cls_session {
 216         struct list_head sess_list;             /* item in session_list */
 217         struct iscsi_transport *transport;
 218         spinlock_t lock;
 219         struct work_struct block_work;
 220         struct work_struct unblock_work;
 221         struct work_struct scan_work;
 222         struct work_struct unbind_work;
 223
 224         /* recovery fields */
 225         int recovery_tmo;
 226         struct delayed_work recovery_work;
 227
 228         unsigned int target_id;
 229         bool ida_used;
 230
 231         /*
 232          * pid of userspace process that created session or -1 if
 233          * created by the kernel.
 234          */
 235         pid_t creator;
 236         int state;
 237         int sid;                                /* session id */
 238         void *dd_data;                          /* LLD private data */
 239         struct device dev;      /* sysfs transport/container device */
 240 };
 241
 242 #define iscsi_dev_to_session(_dev) \
 243         container_of(_dev, struct iscsi_cls_session, dev)
 244
 245 #define transport_class_to_session(_cdev) \
 246         iscsi_dev_to_session(_cdev->parent)
 247
 248 #define iscsi_session_to_shost(_session) \
 249         dev_to_shost(_session->dev.parent)
 250
 251 #define starget_to_session(_stgt) \
 252         iscsi_dev_to_session(_stgt->dev.parent)
 253
 254 struct iscsi_cls_host {
 255         atomic_t nr_scans;
 256         struct mutex mutex;
 257         struct request_queue *bsg_q;
 258         uint32_t port_speed;
 259         uint32_t port_state;
 260 };
 261
 262 #define iscsi_job_to_shost(_job) \
 263         dev_to_shost(_job->dev)
 264
 265 extern void iscsi_host_for_each_session(struct Scsi_Host *shost,
 266                                 void (*fn)(struct iscsi_cls_session *));
 267
 268 struct iscsi_endpoint {
 269         void *dd_data;                  /* LLD private data */
 270         struct device dev;
 271         uint64_t id;
 272         struct iscsi_cls_conn *conn;
 273 };
 274
 275 struct iscsi_iface {
 276         struct device dev;
 277         struct iscsi_transport *transport;
 278         uint32_t iface_type;    /* IPv4 or IPv6 */
 279         uint32_t iface_num;     /* iface number, 0 - n */
 280         void *dd_data;          /* LLD private data */
 281 };
 282
 283 #define iscsi_dev_to_iface(_dev) \
 284         container_of(_dev, struct iscsi_iface, dev)
 285
 286 #define iscsi_iface_to_shost(_iface) \
 287         dev_to_shost(_iface->dev.parent)
 288
 289 /*
 290  * session and connection functions that can be used by HW iSCSI LLDs
 291  */
 292 #define iscsi_cls_session_printk(prefix, _cls_session, fmt, a...) \
 293         dev_printk(prefix, &(_cls_session)->dev, fmt, ##a)
 294
 295 #define iscsi_cls_conn_printk(prefix, _cls_conn, fmt, a...) \
 296         dev_printk(prefix, &(_cls_conn)->dev, fmt, ##a)
 297
 298 extern int iscsi_session_chkready(struct iscsi_cls_session *session);
 299 extern int iscsi_is_session_online(struct iscsi_cls_session *session);
 300 extern struct iscsi_cls_session *iscsi_alloc_session(struct Scsi_Host *shost,
 301                                 struct iscsi_transport *transport, int dd_size);
 302 extern int iscsi_add_session(struct iscsi_cls_session *session,
 303                              unsigned int target_id);
 304 extern int iscsi_session_event(struct iscsi_cls_session *session,
 305                                enum iscsi_uevent_e event);
 306 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
 307                                                 struct iscsi_transport *t,
 308                                                 int dd_size,
 309                                                 unsigned int target_id);
 310 extern void iscsi_remove_session(struct iscsi_cls_session *session);
 311 extern void iscsi_free_session(struct iscsi_cls_session *session);
 312 extern int iscsi_destroy_session(struct iscsi_cls_session *session);
 313 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
 314                                                 int dd_size, uint32_t cid);
 315 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
 316 extern void iscsi_unblock_session(struct iscsi_cls_session *session);
 317 extern void iscsi_block_session(struct iscsi_cls_session *session);
 318 extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time);
 319 extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size);
 320 extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep);
 321 extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle);
 322 extern int iscsi_block_scsi_eh(struct scsi_cmnd *cmd);
 323 extern struct iscsi_iface *iscsi_create_iface(struct Scsi_Host *shost,
 324                                               struct iscsi_transport *t,
 325                                               uint32_t iface_type,
 326                                               uint32_t iface_num, int dd_size);
 327 extern void iscsi_destroy_iface(struct iscsi_iface *iface);
 328 extern struct iscsi_iface *iscsi_lookup_iface(int handle);
 329 extern char *iscsi_get_port_speed_name(struct Scsi_Host *shost);
 330 extern char *iscsi_get_port_state_name(struct Scsi_Host *shost);
 331 extern int iscsi_is_session_dev(const struct device *dev);
 332
 333 #endif