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
 137         /* T10 protection information */
 138         bool                    protected;
 139
 140         /* state set/tested under session->lock */
 141         int                     state;
 142         atomic_t                refcount;
 143         struct list_head        running;        /* running cmd list */
 144         void                    *dd_data;       /* driver/transport data */
 145 };
 146
 147 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
 148 {
 149         return task->unsol_r2t.data_length > task->unsol_r2t.sent;
 150 }
 151
 152 static inline void* iscsi_next_hdr(struct iscsi_task *task)
 153 {
 154         return (void*)task->hdr + task->hdr_len;
 155 }
 156
 157 /* Connection's states */
 158 enum {
 159         ISCSI_CONN_INITIAL_STAGE,
 160         ISCSI_CONN_STARTED,
 161         ISCSI_CONN_STOPPED,
 162         ISCSI_CONN_CLEANUP_WAIT,
 163 };
 164
 165 struct iscsi_conn {
 166         struct iscsi_cls_conn   *cls_conn;      /* ptr to class connection */
 167         void                    *dd_data;       /* iscsi_transport data */
 168         struct iscsi_session    *session;       /* parent session */
 169         /*
 170          * conn_stop() flag: stop to recover, stop to terminate
 171          */
 172         int                     stop_stage;
 173         struct timer_list       transport_timer;
 174         unsigned long           last_recv;
 175         unsigned long           last_ping;
 176         int                     ping_timeout;
 177         int                     recv_timeout;
 178         struct iscsi_task       *ping_task;
 179
 180         /* iSCSI connection-wide sequencing */
 181         uint32_t                exp_statsn;
 182         uint32_t                statsn;
 183
 184         /* control data */
 185         int                     id;             /* CID */
 186         int                     c_stage;        /* connection state */
 187         /*
 188          * Preallocated buffer for pdus that have data but do not
 189          * originate from scsi-ml. We never have two pdus using the
 190          * buffer at the same time. It is only allocated to
 191          * the default max recv size because the pdus we support
 192          * should always fit in this buffer
 193          */
 194         char                    *data;
 195         struct iscsi_task       *login_task;    /* mtask used for login/text */
 196         struct iscsi_task       *task;          /* xmit task in progress */
 197
 198         /* xmit */
 199         struct list_head        mgmtqueue;      /* mgmt (control) xmit queue */
 200         struct list_head        cmdqueue;       /* data-path cmd queue */
 201         struct list_head        requeue;        /* tasks needing another run */
 202         struct work_struct      xmitwork;       /* per-conn. xmit workqueue */
 203         unsigned long           suspend_tx;     /* suspend Tx */
 204         unsigned long           suspend_rx;     /* suspend Rx */
 205
 206         /* abort */
 207         wait_queue_head_t       ehwait;         /* used in eh_abort() */
 208         struct iscsi_tm         tmhdr;
 209         struct timer_list       tmf_timer;
 210         int                     tmf_state;      /* see TMF_INITIAL, etc.*/
 211
 212         /* negotiated params */
 213         unsigned                max_recv_dlength; /* initiator_max_recv_dsl*/
 214         unsigned                max_xmit_dlength; /* target_max_recv_dsl */
 215         int                     hdrdgst_en;
 216         int                     datadgst_en;
 217         int                     ifmarker_en;
 218         int                     ofmarker_en;
 219         /* values userspace uses to id a conn */
 220         int                     persistent_port;
 221         char                    *persistent_address;
 222
 223         unsigned                max_segment_size;
 224         unsigned                tcp_xmit_wsf;
 225         unsigned                tcp_recv_wsf;
 226         uint16_t                keepalive_tmo;
 227         uint16_t                local_port;
 228         uint8_t                 tcp_timestamp_stat;
 229         uint8_t                 tcp_nagle_disable;
 230         uint8_t                 tcp_wsf_disable;
 231         uint8_t                 tcp_timer_scale;
 232         uint8_t                 tcp_timestamp_en;
 233         uint8_t                 fragment_disable;
 234         uint8_t                 ipv4_tos;
 235         uint8_t                 ipv6_traffic_class;
 236         uint8_t                 ipv6_flow_label;
 237         uint8_t                 is_fw_assigned_ipv6;
 238         char                    *local_ipaddr;
 239
 240         /* MIB-statistics */
 241         uint64_t                txdata_octets;
 242         uint64_t                rxdata_octets;
 243         uint32_t                scsicmd_pdus_cnt;
 244         uint32_t                dataout_pdus_cnt;
 245         uint32_t                scsirsp_pdus_cnt;
 246         uint32_t                datain_pdus_cnt;
 247         uint32_t                r2t_pdus_cnt;
 248         uint32_t                tmfcmd_pdus_cnt;
 249         int32_t                 tmfrsp_pdus_cnt;
 250
 251         /* custom statistics */
 252         uint32_t                eh_abort_cnt;
 253         uint32_t                fmr_unalign_cnt;
 254 };
 255
 256 struct iscsi_pool {
 257         struct kfifo            queue;          /* FIFO Queue */
 258         void                    **pool;         /* Pool of elements */
 259         int                     max;            /* Max number of elements */
 260 };
 261
 262 /* Session's states */
 263 enum {
 264         ISCSI_STATE_FREE = 1,
 265         ISCSI_STATE_LOGGED_IN,
 266         ISCSI_STATE_FAILED,
 267         ISCSI_STATE_TERMINATE,
 268         ISCSI_STATE_IN_RECOVERY,
 269         ISCSI_STATE_RECOVERY_FAILED,
 270         ISCSI_STATE_LOGGING_OUT,
 271 };
 272
 273 struct iscsi_session {
 274         struct iscsi_cls_session *cls_session;
 275         /*
 276          * Syncs up the scsi eh thread with the iscsi eh thread when sending
 277          * task management functions. This must be taken before the session
 278          * and recv lock.
 279          */
 280         struct mutex            eh_mutex;
 281
 282         /* iSCSI session-wide sequencing */
 283         uint32_t                cmdsn;
 284         uint32_t                exp_cmdsn;
 285         uint32_t                max_cmdsn;
 286
 287         /* This tracks the reqs queued into the initiator */
 288         uint32_t                queued_cmdsn;
 289
 290         /* configuration */
 291         int                     abort_timeout;
 292         int                     lu_reset_timeout;
 293         int                     tgt_reset_timeout;
 294         int                     initial_r2t_en;
 295         unsigned short          max_r2t;
 296         int                     imm_data_en;
 297         unsigned                first_burst;
 298         unsigned                max_burst;
 299         int                     time2wait;
 300         int                     time2retain;
 301         int                     pdu_inorder_en;
 302         int                     dataseq_inorder_en;
 303         int                     erl;
 304         int                     fast_abort;
 305         int                     tpgt;
 306         char                    *username;
 307         char                    *username_in;
 308         char                    *password;
 309         char                    *password_in;
 310         char                    *targetname;
 311         char                    *targetalias;
 312         char                    *ifacename;
 313         char                    *initiatorname;
 314         char                    *boot_root;
 315         char                    *boot_nic;
 316         char                    *boot_target;
 317         char                    *portal_type;
 318         char                    *discovery_parent_type;
 319         uint16_t                discovery_parent_idx;
 320         uint16_t                def_taskmgmt_tmo;
 321         uint16_t                tsid;
 322         uint8_t                 auto_snd_tgt_disable;
 323         uint8_t                 discovery_sess;
 324         uint8_t                 chap_auth_en;
 325         uint8_t                 discovery_logout_en;
 326         uint8_t                 bidi_chap_en;
 327         uint8_t                 discovery_auth_optional;
 328         uint8_t                 isid[ISID_SIZE];
 329
 330         /* control data */
 331         struct iscsi_transport  *tt;
 332         struct Scsi_Host        *host;
 333         struct iscsi_conn       *leadconn;      /* leading connection */
 334         /* Between the forward and the backward locks exists a strict locking
 335          * hierarchy. The mutual exclusion zone protected by the forward lock
 336          * can enclose the mutual exclusion zone protected by the backward lock
 337          * but not vice versa.
 338          */
 339         spinlock_t              frwd_lock;      /* protects session state, *
 340                                                  * cmdsn, queued_cmdsn     *
 341                                                  * session resources:      *
 342                                                  * - cmdpool kfifo_out ,   *
 343                                                  * - mgmtpool,             */
 344         spinlock_t              back_lock;      /* protects cmdsn_exp      *
 345                                                  * cmdsn_max,              *
 346                                                  * cmdpool kfifo_in        */
 347         int                     state;          /* session state           */
 348         int                     age;            /* counts session re-opens */
 349
 350         int                     scsi_cmds_max;  /* max scsi commands */
 351         int                     cmds_max;       /* size of cmds array */
 352         struct iscsi_task       **cmds;         /* Original Cmds arr */
 353         struct iscsi_pool       cmdpool;        /* PDU's pool */
 354         void                    *dd_data;       /* LLD private data */
 355 };
 356
 357 enum {
 358         ISCSI_HOST_SETUP,
 359         ISCSI_HOST_REMOVED,
 360 };
 361
 362 struct iscsi_host {
 363         char                    *initiatorname;
 364         /* hw address or netdev iscsi connection is bound to */
 365         char                    *hwaddress;
 366         char                    *netdev;
 367
 368         wait_queue_head_t       session_removal_wq;
 369         /* protects sessions and state */
 370         spinlock_t              lock;
 371         int                     num_sessions;
 372         int                     state;
 373
 374         struct workqueue_struct *workq;
 375         char                    workq_name[20];
 376 };
 377
 378 /*
 379  * scsi host template
 380  */
 381 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
 382 extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
 383 extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
 384 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
 385 extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
 386 extern enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc);
 387
 388 /*
 389  * iSCSI host helpers.
 390  */
 391 #define iscsi_host_priv(_shost) \
 392         (shost_priv(_shost) + sizeof(struct iscsi_host))
 393
 394 extern int iscsi_host_set_param(struct Scsi_Host *shost,
 395                                 enum iscsi_host_param param, char *buf,
 396                                 int buflen);
 397 extern int iscsi_host_get_param(struct Scsi_Host *shost,
 398                                 enum iscsi_host_param param, char *buf);
 399 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
 400 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
 401                                           int dd_data_size,
 402                                           bool xmit_can_sleep);
 403 extern void iscsi_host_remove(struct Scsi_Host *shost);
 404 extern void iscsi_host_free(struct Scsi_Host *shost);
 405 extern int iscsi_target_alloc(struct scsi_target *starget);
 406
 407 /*
 408  * session management
 409  */
 410 extern struct iscsi_cls_session *
 411 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
 412                     uint16_t, int, int, uint32_t, unsigned int);
 413 extern void iscsi_session_teardown(struct iscsi_cls_session *);
 414 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
 415 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
 416                            enum iscsi_param param, char *buf, int buflen);
 417 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
 418                                    enum iscsi_param param, char *buf);
 419
 420 #define iscsi_session_printk(prefix, _sess, fmt, a...)  \
 421         iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
 422
 423 /*
 424  * connection management
 425  */
 426 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
 427                                                int, uint32_t);
 428 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
 429 extern int iscsi_conn_start(struct iscsi_cls_conn *);
 430 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
 431 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
 432                            int);
 433 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
 434 extern void iscsi_session_failure(struct iscsi_session *session,
 435                                   enum iscsi_err err);
 436 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
 437                                 enum iscsi_param param, char *buf);
 438 extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
 439                                      enum iscsi_param param, char *buf);
 440 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
 441 extern void iscsi_suspend_queue(struct iscsi_conn *conn);
 442 extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
 443
 444 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
 445         iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
 446                               fmt, ##a)
 447
 448 /*
 449  * pdu and task processing
 450  */
 451 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
 452 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
 453                                     struct iscsi_r2t_info *r2t,
 454                                     struct iscsi_data *hdr);
 455 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
 456                                 char *, uint32_t);
 457 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 458                               char *, int);
 459 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 460                                 char *, int);
 461 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
 462 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
 463 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
 464 extern void iscsi_requeue_task(struct iscsi_task *task);
 465 extern void iscsi_put_task(struct iscsi_task *task);
 466 extern void __iscsi_put_task(struct iscsi_task *task);
 467 extern void __iscsi_get_task(struct iscsi_task *task);
 468 extern void iscsi_complete_scsi_task(struct iscsi_task *task,
 469                                      uint32_t exp_cmdsn, uint32_t max_cmdsn);
 470
 471 /*
 472  * generic helpers
 473  */
 474 extern void iscsi_pool_free(struct iscsi_pool *);
 475 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
 476 extern int iscsi_switch_str_param(char **, char *);
 477
 478 /*
 479  * inline functions to deal with padding.
 480  */
 481 static inline unsigned int
 482 iscsi_padded(unsigned int len)
 483 {
 484         return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
 485 }
 486
 487 static inline unsigned int
 488 iscsi_padding(unsigned int len)
 489 {
 490         len &= (ISCSI_PAD_LEN - 1);
 491         if (len)
 492                 len = ISCSI_PAD_LEN - len;
 493         return len;
 494 }
 495
 496 #endif