include/scsi/libiscsi.h

   1 /*
   2  * iSCSI lib definitions
   3  *
   4  * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
   5  * Copyright (C) 2004 - 2006 Mike Christie
   6  * Copyright (C) 2004 - 2005 Dmitry Yusupov
   7  * Copyright (C) 2004 - 2005 Alex Aizman
   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 LIBISCSI_H
  24 #define LIBISCSI_H
  25
  26 #include <linux/types.h>
  27 #include <linux/wait.h>
  28 #include <linux/mutex.h>
  29 #include <linux/timer.h>
  30 #include <linux/workqueue.h>
  31 #include <linux/kfifo.h>
  32 #include <scsi/iscsi_proto.h>
  33 #include <scsi/iscsi_if.h>
  34 #include <scsi/scsi_transport_iscsi.h>
  35
  36 struct scsi_transport_template;
  37 struct scsi_host_template;
  38 struct scsi_device;
  39 struct Scsi_Host;
  40 struct scsi_target;
  41 struct scsi_cmnd;
  42 struct socket;
  43 struct iscsi_transport;
  44 struct iscsi_cls_session;
  45 struct iscsi_cls_conn;
  46 struct iscsi_session;
  47 struct iscsi_nopin;
  48 struct device;
  49
  50 #define ISCSI_DEF_XMIT_CMDS_MAX 128     /* must be power of 2 */
  51 #define ISCSI_MGMT_CMDS_MAX     15
  52
  53 #define ISCSI_DEF_CMD_PER_LUN   32
  54
  55 /* Task Mgmt states */
  56 enum {
  57         TMF_INITIAL,
  58         TMF_QUEUED,
  59         TMF_SUCCESS,
  60         TMF_FAILED,
  61         TMF_TIMEDOUT,
  62         TMF_NOT_FOUND,
  63 };
  64
  65 #define ISID_SIZE                       6
  66
  67 /* Connection suspend "bit" */
  68 #define ISCSI_SUSPEND_BIT               1
  69
  70 #define ISCSI_ITT_MASK                  0x1fff
  71 #define ISCSI_TOTAL_CMDS_MAX            4096
  72 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
  73 #define ISCSI_TOTAL_CMDS_MIN            16
  74 #define ISCSI_AGE_SHIFT                 28
  75 #define ISCSI_AGE_MASK                  0xf
  76
  77 #define ISCSI_ADDRESS_BUF_LEN           64
  78
  79 enum {
  80         /* this is the maximum possible storage for AHSs */
  81         ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
  82                                 sizeof(struct iscsi_rlength_ahdr),
  83         ISCSI_DIGEST_SIZE = sizeof(__u32),
  84 };
  85
  86
  87 enum {
  88         ISCSI_TASK_FREE,
  89         ISCSI_TASK_COMPLETED,
  90         ISCSI_TASK_PENDING,
  91         ISCSI_TASK_RUNNING,
  92         ISCSI_TASK_ABRT_TMF,            /* aborted due to TMF */
  93         ISCSI_TASK_ABRT_SESS_RECOV,     /* aborted due to session recovery */
  94         ISCSI_TASK_REQUEUE_SCSIQ,       /* qcmd requeueing to scsi-ml */
  95 };
  96
  97 struct iscsi_r2t_info {
  98         __be32                  ttt;            /* copied from R2T */
  99         __be32                  exp_statsn;     /* copied from R2T */
 100         uint32_t                data_length;    /* copied from R2T */
 101         uint32_t                data_offset;    /* copied from R2T */
 102         int                     data_count;     /* DATA-Out payload progress */
 103         int                     datasn;
 104         /* LLDs should set/update these values */
 105         int                     sent;           /* R2T sequence progress */
 106 };
 107
 108 struct iscsi_task {
 109         /*
 110          * Because LLDs allocate their hdr differently, this is a pointer
 111          * and length to that storage. It must be setup at session
 112          * creation time.
 113          */
 114         struct iscsi_hdr        *hdr;
 115         unsigned short          hdr_max;
 116         unsigned short          hdr_len;        /* accumulated size of hdr used */
 117         /* copied values in case we need to send tmfs */
 118         itt_t                   hdr_itt;
 119         __be32                  cmdsn;
 120         struct scsi_lun         lun;
 121
 122         int                     itt;            /* this ITT */
 123
 124         unsigned                imm_count;      /* imm-data (bytes)   */
 125         /* offset in unsolicited stream (bytes); */
 126         struct iscsi_r2t_info   unsol_r2t;
 127         char                    *data;          /* mgmt payload */
 128         unsigned                data_count;
 129         struct scsi_cmnd        *sc;            /* associated SCSI cmd*/
 130         struct iscsi_conn       *conn;          /* used connection    */
 131
 132         /* data processing tracking */
 133         unsigned long           last_xfer;
 134         unsigned long           last_timeout;
 135         bool                    have_checked_conn;
 136         /* state set/tested under session->lock */
 137         int                     state;
 138         atomic_t                refcount;
 139         struct list_head        running;        /* running cmd list */
 140         void                    *dd_data;       /* driver/transport data */
 141 };
 142
 143 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
 144 {
 145         return task->unsol_r2t.data_length > task->unsol_r2t.sent;
 146 }
 147
 148 static inline void* iscsi_next_hdr(struct iscsi_task *task)
 149 {
 150         return (void*)task->hdr + task->hdr_len;
 151 }
 152
 153 /* Connection's states */
 154 enum {
 155         ISCSI_CONN_INITIAL_STAGE,
 156         ISCSI_CONN_STARTED,
 157         ISCSI_CONN_STOPPED,
 158         ISCSI_CONN_CLEANUP_WAIT,
 159 };
 160
 161 struct iscsi_conn {
 162         struct iscsi_cls_conn   *cls_conn;      /* ptr to class connection */
 163         void                    *dd_data;       /* iscsi_transport data */
 164         struct iscsi_session    *session;       /* parent session */
 165         /*
 166          * conn_stop() flag: stop to recover, stop to terminate
 167          */
 168         int                     stop_stage;
 169         struct timer_list       transport_timer;
 170         unsigned long           last_recv;
 171         unsigned long           last_ping;
 172         int                     ping_timeout;
 173         int                     recv_timeout;
 174         struct iscsi_task       *ping_task;
 175
 176         /* iSCSI connection-wide sequencing */
 177         uint32_t                exp_statsn;
 178         uint32_t                statsn;
 179
 180         /* control data */
 181         int                     id;             /* CID */
 182         int                     c_stage;        /* connection state */
 183         /*
 184          * Preallocated buffer for pdus that have data but do not
 185          * originate from scsi-ml. We never have two pdus using the
 186          * buffer at the same time. It is only allocated to
 187          * the default max recv size because the pdus we support
 188          * should always fit in this buffer
 189          */
 190         char                    *data;
 191         struct iscsi_task       *login_task;    /* mtask used for login/text */
 192         struct iscsi_task       *task;          /* xmit task in progress */
 193
 194         /* xmit */
 195         struct list_head        mgmtqueue;      /* mgmt (control) xmit queue */
 196         struct list_head        cmdqueue;       /* data-path cmd queue */
 197         struct list_head        requeue;        /* tasks needing another run */
 198         struct work_struct      xmitwork;       /* per-conn. xmit workqueue */
 199         unsigned long           suspend_tx;     /* suspend Tx */
 200         unsigned long           suspend_rx;     /* suspend Rx */
 201
 202         /* abort */
 203         wait_queue_head_t       ehwait;         /* used in eh_abort() */
 204         struct iscsi_tm         tmhdr;
 205         struct timer_list       tmf_timer;
 206         int                     tmf_state;      /* see TMF_INITIAL, etc.*/
 207
 208         /* negotiated params */
 209         unsigned                max_recv_dlength; /* initiator_max_recv_dsl*/
 210         unsigned                max_xmit_dlength; /* target_max_recv_dsl */
 211         int                     hdrdgst_en;
 212         int                     datadgst_en;
 213         int                     ifmarker_en;
 214         int                     ofmarker_en;
 215         /* values userspace uses to id a conn */
 216         int                     persistent_port;
 217         char                    *persistent_address;
 218
 219         unsigned                max_segment_size;
 220         unsigned                tcp_xmit_wsf;
 221         unsigned                tcp_recv_wsf;
 222         uint16_t                keepalive_tmo;
 223         uint16_t                local_port;
 224         uint8_t                 tcp_timestamp_stat;
 225         uint8_t                 tcp_nagle_disable;
 226         uint8_t                 tcp_wsf_disable;
 227         uint8_t                 tcp_timer_scale;
 228         uint8_t                 tcp_timestamp_en;
 229         uint8_t                 fragment_disable;
 230         uint8_t                 ipv4_tos;
 231         uint8_t                 ipv6_traffic_class;
 232         uint8_t                 ipv6_flow_label;
 233         uint8_t                 is_fw_assigned_ipv6;
 234
 235         /* MIB-statistics */
 236         uint64_t                txdata_octets;
 237         uint64_t                rxdata_octets;
 238         uint32_t                scsicmd_pdus_cnt;
 239         uint32_t                dataout_pdus_cnt;
 240         uint32_t                scsirsp_pdus_cnt;
 241         uint32_t                datain_pdus_cnt;
 242         uint32_t                r2t_pdus_cnt;
 243         uint32_t                tmfcmd_pdus_cnt;
 244         int32_t                 tmfrsp_pdus_cnt;
 245
 246         /* custom statistics */
 247         uint32_t                eh_abort_cnt;
 248         uint32_t                fmr_unalign_cnt;
 249 };
 250
 251 struct iscsi_pool {
 252         struct kfifo            queue;          /* FIFO Queue */
 253         void                    **pool;         /* Pool of elements */
 254         int                     max;            /* Max number of elements */
 255 };
 256
 257 /* Session's states */
 258 enum {
 259         ISCSI_STATE_FREE = 1,
 260         ISCSI_STATE_LOGGED_IN,
 261         ISCSI_STATE_FAILED,
 262         ISCSI_STATE_TERMINATE,
 263         ISCSI_STATE_IN_RECOVERY,
 264         ISCSI_STATE_RECOVERY_FAILED,
 265         ISCSI_STATE_LOGGING_OUT,
 266 };
 267
 268 struct iscsi_session {
 269         struct iscsi_cls_session *cls_session;
 270         /*
 271          * Syncs up the scsi eh thread with the iscsi eh thread when sending
 272          * task management functions. This must be taken before the session
 273          * and recv lock.
 274          */
 275         struct mutex            eh_mutex;
 276
 277         /* iSCSI session-wide sequencing */
 278         uint32_t                cmdsn;
 279         uint32_t                exp_cmdsn;
 280         uint32_t                max_cmdsn;
 281
 282         /* This tracks the reqs queued into the initiator */
 283         uint32_t                queued_cmdsn;
 284
 285         /* configuration */
 286         int                     abort_timeout;
 287         int                     lu_reset_timeout;
 288         int                     tgt_reset_timeout;
 289         int                     initial_r2t_en;
 290         unsigned short          max_r2t;
 291         int                     imm_data_en;
 292         unsigned                first_burst;
 293         unsigned                max_burst;
 294         int                     time2wait;
 295         int                     time2retain;
 296         int                     pdu_inorder_en;
 297         int                     dataseq_inorder_en;
 298         int                     erl;
 299         int                     fast_abort;
 300         int                     tpgt;
 301         char                    *username;
 302         char                    *username_in;
 303         char                    *password;
 304         char                    *password_in;
 305         char                    *targetname;
 306         char                    *targetalias;
 307         char                    *ifacename;
 308         char                    *initiatorname;
 309         char                    *boot_root;
 310         char                    *boot_nic;
 311         char                    *boot_target;
 312         char                    *portal_type;
 313         char                    *discovery_parent_type;
 314         uint16_t                discovery_parent_idx;
 315         uint16_t                def_taskmgmt_tmo;
 316         uint16_t                tsid;
 317         uint8_t                 auto_snd_tgt_disable;
 318         uint8_t                 discovery_sess;
 319         uint8_t                 chap_auth_en;
 320         uint8_t                 discovery_logout_en;
 321         uint8_t                 bidi_chap_en;
 322         uint8_t                 discovery_auth_optional;
 323         uint8_t                 isid[ISID_SIZE];
 324
 325         /* control data */
 326         struct iscsi_transport  *tt;
 327         struct Scsi_Host        *host;
 328         struct iscsi_conn       *leadconn;      /* leading connection */
 329         spinlock_t              lock;           /* protects session state, *
 330                                                  * sequence numbers,       *
 331                                                  * session resources:      *
 332                                                  * - cmdpool,              *
 333                                                  * - mgmtpool,             *
 334                                                  * - r2tpool               */
 335         int                     state;          /* session state           */
 336         int                     age;            /* counts session re-opens */
 337
 338         int                     scsi_cmds_max;  /* max scsi commands */
 339         int                     cmds_max;       /* size of cmds array */
 340         struct iscsi_task       **cmds;         /* Original Cmds arr */
 341         struct iscsi_pool       cmdpool;        /* PDU's pool */
 342         void                    *dd_data;       /* LLD private data */
 343 };
 344
 345 enum {
 346         ISCSI_HOST_SETUP,
 347         ISCSI_HOST_REMOVED,
 348 };
 349
 350 struct iscsi_host {
 351         char                    *initiatorname;
 352         /* hw address or netdev iscsi connection is bound to */
 353         char                    *hwaddress;
 354         char                    *netdev;
 355
 356         wait_queue_head_t       session_removal_wq;
 357         /* protects sessions and state */
 358         spinlock_t              lock;
 359         int                     num_sessions;
 360         int                     state;
 361
 362         struct workqueue_struct *workq;
 363         char                    workq_name[20];
 364 };
 365
 366 /*
 367  * scsi host template
 368  */
 369 extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth,
 370                                     int reason);
 371 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
 372 extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
 373 extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
 374 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
 375 extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
 376
 377 /*
 378  * iSCSI host helpers.
 379  */
 380 #define iscsi_host_priv(_shost) \
 381         (shost_priv(_shost) + sizeof(struct iscsi_host))
 382
 383 extern int iscsi_host_set_param(struct Scsi_Host *shost,
 384                                 enum iscsi_host_param param, char *buf,
 385                                 int buflen);
 386 extern int iscsi_host_get_param(struct Scsi_Host *shost,
 387                                 enum iscsi_host_param param, char *buf);
 388 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
 389 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
 390                                           int dd_data_size,
 391                                           bool xmit_can_sleep);
 392 extern void iscsi_host_remove(struct Scsi_Host *shost);
 393 extern void iscsi_host_free(struct Scsi_Host *shost);
 394 extern int iscsi_target_alloc(struct scsi_target *starget);
 395
 396 /*
 397  * session management
 398  */
 399 extern struct iscsi_cls_session *
 400 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
 401                     uint16_t, int, int, uint32_t, unsigned int);
 402 extern void iscsi_session_teardown(struct iscsi_cls_session *);
 403 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
 404 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
 405                            enum iscsi_param param, char *buf, int buflen);
 406 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
 407                                    enum iscsi_param param, char *buf);
 408
 409 #define iscsi_session_printk(prefix, _sess, fmt, a...)  \
 410         iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
 411
 412 /*
 413  * connection management
 414  */
 415 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
 416                                                int, uint32_t);
 417 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
 418 extern int iscsi_conn_start(struct iscsi_cls_conn *);
 419 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
 420 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
 421                            int);
 422 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
 423 extern void iscsi_session_failure(struct iscsi_session *session,
 424                                   enum iscsi_err err);
 425 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
 426                                 enum iscsi_param param, char *buf);
 427 extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
 428                                      enum iscsi_param param, char *buf);
 429 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
 430 extern void iscsi_suspend_queue(struct iscsi_conn *conn);
 431 extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
 432
 433 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
 434         iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
 435                               fmt, ##a)
 436
 437 /*
 438  * pdu and task processing
 439  */
 440 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
 441 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
 442                                     struct iscsi_r2t_info *r2t,
 443                                     struct iscsi_data *hdr);
 444 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
 445                                 char *, uint32_t);
 446 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 447                               char *, int);
 448 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 449                                 char *, int);
 450 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
 451 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
 452 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
 453 extern void iscsi_requeue_task(struct iscsi_task *task);
 454 extern void iscsi_put_task(struct iscsi_task *task);
 455 extern void __iscsi_put_task(struct iscsi_task *task);
 456 extern void __iscsi_get_task(struct iscsi_task *task);
 457 extern void iscsi_complete_scsi_task(struct iscsi_task *task,
 458                                      uint32_t exp_cmdsn, uint32_t max_cmdsn);
 459
 460 /*
 461  * generic helpers
 462  */
 463 extern void iscsi_pool_free(struct iscsi_pool *);
 464 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
 465 extern int iscsi_switch_str_param(char **, char *);
 466
 467 /*
 468  * inline functions to deal with padding.
 469  */
 470 static inline unsigned int
 471 iscsi_padded(unsigned int len)
 472 {
 473         return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
 474 }
 475
 476 static inline unsigned int
 477 iscsi_padding(unsigned int len)
 478 {
 479         len &= (ISCSI_PAD_LEN - 1);
 480         if (len)
 481                 len = ISCSI_PAD_LEN - len;
 482         return len;
 483 }
 484
 485 #endif