linux/include/scsi/libiscsi.h
<<
>>
Prefs 
   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
  36struct scsi_transport_template;
  37struct scsi_host_template;
  38struct scsi_device;
  39struct Scsi_Host;
  40struct scsi_target;
  41struct scsi_cmnd;
  42struct socket;
  43struct iscsi_transport;
  44struct iscsi_cls_session;
  45struct iscsi_cls_conn;
  46struct iscsi_session;
  47struct iscsi_nopin;
  48struct 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 */
  56enum {
  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
  79enum {
  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
  87enum {
  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
  97struct 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
 108struct 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
 147static 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
 152static inline void* iscsi_next_hdr(struct iscsi_task *task)
 153{
 154        return (void*)task->hdr + task->hdr_len;
 155}
 156
 157/* Connection's states */
 158enum {
 159        ISCSI_CONN_INITIAL_STAGE,
 160        ISCSI_CONN_STARTED,
 161        ISCSI_CONN_STOPPED,
 162        ISCSI_CONN_CLEANUP_WAIT,
 163};
 164
 165struct 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
 256struct 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 */
 263enum {
 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
 273struct 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
 357enum {
 358        ISCSI_HOST_SETUP,
 359        ISCSI_HOST_REMOVED,
 360};
 361
 362struct 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 */
 381extern int iscsi_eh_abort(struct scsi_cmnd *sc);
 382extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
 383extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
 384extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
 385extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
 386
 387/*
 388 * iSCSI host helpers.
 389 */
 390#define iscsi_host_priv(_shost) \
 391        (shost_priv(_shost) + sizeof(struct iscsi_host))
 392
 393extern int iscsi_host_set_param(struct Scsi_Host *shost,
 394                                enum iscsi_host_param param, char *buf,
 395                                int buflen);
 396extern int iscsi_host_get_param(struct Scsi_Host *shost,
 397                                enum iscsi_host_param param, char *buf);
 398extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
 399extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
 400                                          int dd_data_size,
 401                                          bool xmit_can_sleep);
 402extern void iscsi_host_remove(struct Scsi_Host *shost);
 403extern void iscsi_host_free(struct Scsi_Host *shost);
 404extern int iscsi_target_alloc(struct scsi_target *starget);
 405
 406/*
 407 * session management
 408 */
 409extern struct iscsi_cls_session *
 410iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
 411                    uint16_t, int, int, uint32_t, unsigned int);
 412extern void iscsi_session_teardown(struct iscsi_cls_session *);
 413extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
 414extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
 415                           enum iscsi_param param, char *buf, int buflen);
 416extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
 417                                   enum iscsi_param param, char *buf);
 418
 419#define iscsi_session_printk(prefix, _sess, fmt, a...)  \
 420        iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
 421
 422/*
 423 * connection management
 424 */
 425extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
 426                                               int, uint32_t);
 427extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
 428extern int iscsi_conn_start(struct iscsi_cls_conn *);
 429extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
 430extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
 431                           int);
 432extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
 433extern void iscsi_session_failure(struct iscsi_session *session,
 434                                  enum iscsi_err err);
 435extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
 436                                enum iscsi_param param, char *buf);
 437extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
 438                                     enum iscsi_param param, char *buf);
 439extern void iscsi_suspend_tx(struct iscsi_conn *conn);
 440extern void iscsi_suspend_queue(struct iscsi_conn *conn);
 441extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
 442
 443#define iscsi_conn_printk(prefix, _c, fmt, a...) \
 444        iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
 445                              fmt, ##a)
 446
 447/*
 448 * pdu and task processing
 449 */
 450extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
 451extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
 452                                    struct iscsi_r2t_info *r2t,
 453                                    struct iscsi_data *hdr);
 454extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
 455                                char *, uint32_t);
 456extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 457                              char *, int);
 458extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 459                                char *, int);
 460extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
 461extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
 462extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
 463extern void iscsi_requeue_task(struct iscsi_task *task);
 464extern void iscsi_put_task(struct iscsi_task *task);
 465extern void __iscsi_put_task(struct iscsi_task *task);
 466extern void __iscsi_get_task(struct iscsi_task *task);
 467extern void iscsi_complete_scsi_task(struct iscsi_task *task,
 468                                     uint32_t exp_cmdsn, uint32_t max_cmdsn);
 469
 470/*
 471 * generic helpers
 472 */
 473extern void iscsi_pool_free(struct iscsi_pool *);
 474extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
 475extern int iscsi_switch_str_param(char **, char *);
 476
 477/*
 478 * inline functions to deal with padding.
 479 */
 480static inline unsigned int
 481iscsi_padded(unsigned int len)
 482{
 483        return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
 484}
 485
 486static inline unsigned int
 487iscsi_padding(unsigned int len)
 488{
 489        len &= (ISCSI_PAD_LEN - 1);
 490        if (len)
 491                len = ISCSI_PAD_LEN - len;
 492        return len;
 493}
 494
 495#endif
 496
Hosted by Missing Link Electronics. The original LXR software by the LXR community, this experimental version by lxr@linux.no.