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/mutex.h>
  28 #include <linux/timer.h>
  29 #include <linux/workqueue.h>
  30 #include <scsi/iscsi_proto.h>
  31 #include <scsi/iscsi_if.h>
  32
  33 struct scsi_transport_template;
  34 struct scsi_device;
  35 struct Scsi_Host;
  36 struct scsi_cmnd;
  37 struct socket;
  38 struct iscsi_transport;
  39 struct iscsi_cls_session;
  40 struct iscsi_cls_conn;
  41 struct iscsi_session;
  42 struct iscsi_nopin;
  43
  44 /* #define DEBUG_SCSI */
  45 #ifdef DEBUG_SCSI
  46 #define debug_scsi(fmt...) printk(KERN_INFO "iscsi: " fmt)
  47 #else
  48 #define debug_scsi(fmt...)
  49 #endif
  50
  51 #define ISCSI_DEF_XMIT_CMDS_MAX 128     /* must be power of 2 */
  52 #define ISCSI_MGMT_CMDS_MAX     16      /* must be power of 2 */
  53
  54 #define ISCSI_MGMT_ITT_OFFSET   0xa00
  55
  56 #define ISCSI_DEF_CMD_PER_LUN           32
  57 #define ISCSI_MAX_CMD_PER_LUN           128
  58
  59 /* Task Mgmt states */
  60 enum {
  61         TMF_INITIAL,
  62         TMF_QUEUED,
  63         TMF_SUCCESS,
  64         TMF_FAILED,
  65         TMF_TIMEDOUT,
  66         TMF_NOT_FOUND,
  67 };
  68
  69 /* Connection suspend "bit" */
  70 #define ISCSI_SUSPEND_BIT               1
  71
  72 #define ISCSI_ITT_MASK                  (0xfff)
  73 #define ISCSI_CID_SHIFT                 12
  74 #define ISCSI_CID_MASK                  (0xffff << ISCSI_CID_SHIFT)
  75 #define ISCSI_AGE_SHIFT                 28
  76 #define ISCSI_AGE_MASK                  (0xf << ISCSI_AGE_SHIFT)
  77
  78 #define ISCSI_ADDRESS_BUF_LEN           64
  79
  80 struct iscsi_mgmt_task {
  81         /*
  82          * Becuae LLDs allocate their hdr differently, this is a pointer to
  83          * that storage. It must be setup at session creation time.
  84          */
  85         struct iscsi_hdr        *hdr;
  86         char                    *data;          /* mgmt payload */
  87         unsigned                data_count;     /* counts data to be sent */
  88         uint32_t                itt;            /* this ITT */
  89         void                    *dd_data;       /* driver/transport data */
  90         struct list_head        running;
  91 };
  92
  93 enum {
  94         ISCSI_TASK_COMPLETED,
  95         ISCSI_TASK_PENDING,
  96         ISCSI_TASK_RUNNING,
  97 };
  98
  99 struct iscsi_cmd_task {
 100         /*
 101          * Becuae LLDs allocate their hdr differently, this is a pointer to
 102          * that storage. It must be setup at session creation time.
 103          */
 104         struct iscsi_cmd        *hdr;
 105         int                     itt;            /* this ITT */
 106
 107         uint32_t                unsol_datasn;
 108         unsigned                imm_count;      /* imm-data (bytes)   */
 109         unsigned                unsol_count;    /* unsolicited (bytes)*/
 110         /* offset in unsolicited stream (bytes); */
 111         unsigned                unsol_offset;
 112         unsigned                data_count;     /* remaining Data-Out */
 113         struct scsi_cmnd        *sc;            /* associated SCSI cmd*/
 114         struct iscsi_conn       *conn;          /* used connection    */
 115
 116         /* state set/tested under session->lock */
 117         int                     state;
 118         atomic_t                refcount;
 119         struct list_head        running;        /* running cmd list */
 120         void                    *dd_data;       /* driver/transport data */
 121 };
 122
 123 struct iscsi_conn {
 124         struct iscsi_cls_conn   *cls_conn;      /* ptr to class connection */
 125         void                    *dd_data;       /* iscsi_transport data */
 126         struct iscsi_session    *session;       /* parent session */
 127         /*
 128          * LLDs should set this lock. It protects the transport recv
 129          * code
 130          */
 131         rwlock_t                *recv_lock;
 132         /*
 133          * conn_stop() flag: stop to recover, stop to terminate
 134          */
 135         int                     stop_stage;
 136
 137         /* iSCSI connection-wide sequencing */
 138         uint32_t                exp_statsn;
 139
 140         /* control data */
 141         int                     id;             /* CID */
 142         int                     c_stage;        /* connection state */
 143         /*
 144          * Preallocated buffer for pdus that have data but do not
 145          * originate from scsi-ml. We never have two pdus using the
 146          * buffer at the same time. It is only allocated to
 147          * the default max recv size because the pdus we support
 148          * should always fit in this buffer
 149          */
 150         char                    *data;
 151         struct iscsi_mgmt_task  *login_mtask;   /* mtask used for login/text */
 152         struct iscsi_mgmt_task  *mtask;         /* xmit mtask in progress */
 153         struct iscsi_cmd_task   *ctask;         /* xmit ctask in progress */
 154
 155         /* xmit */
 156         struct list_head        mgmtqueue;      /* mgmt (control) xmit queue */
 157         struct list_head        mgmt_run_list;  /* list of control tasks */
 158         struct list_head        xmitqueue;      /* data-path cmd queue */
 159         struct list_head        run_list;       /* list of cmds in progress */
 160         struct list_head        requeue;        /* tasks needing another run */
 161         struct work_struct      xmitwork;       /* per-conn. xmit workqueue */
 162         unsigned long           suspend_tx;     /* suspend Tx */
 163         unsigned long           suspend_rx;     /* suspend Rx */
 164
 165         /* abort */
 166         wait_queue_head_t       ehwait;         /* used in eh_abort() */
 167         struct iscsi_tm         tmhdr;
 168         struct timer_list       tmf_timer;
 169         int                     tmf_state;      /* see TMF_INITIAL, etc.*/
 170
 171         /* negotiated params */
 172         unsigned                max_recv_dlength; /* initiator_max_recv_dsl*/
 173         unsigned                max_xmit_dlength; /* target_max_recv_dsl */
 174         int                     hdrdgst_en;
 175         int                     datadgst_en;
 176         int                     ifmarker_en;
 177         int                     ofmarker_en;
 178         /* values userspace uses to id a conn */
 179         int                     persistent_port;
 180         char                    *persistent_address;
 181         /* remote portal currently connected to */
 182         int                     portal_port;
 183         char                    portal_address[ISCSI_ADDRESS_BUF_LEN];
 184         /* local address */
 185         int                     local_port;
 186         char                    local_address[ISCSI_ADDRESS_BUF_LEN];
 187
 188         /* MIB-statistics */
 189         uint64_t                txdata_octets;
 190         uint64_t                rxdata_octets;
 191         uint32_t                scsicmd_pdus_cnt;
 192         uint32_t                dataout_pdus_cnt;
 193         uint32_t                scsirsp_pdus_cnt;
 194         uint32_t                datain_pdus_cnt;
 195         uint32_t                r2t_pdus_cnt;
 196         uint32_t                tmfcmd_pdus_cnt;
 197         int32_t                 tmfrsp_pdus_cnt;
 198
 199         /* custom statistics */
 200         uint32_t                eh_abort_cnt;
 201 };
 202
 203 struct iscsi_queue {
 204         struct kfifo            *queue;         /* FIFO Queue */
 205         void                    **pool;         /* Pool of elements */
 206         int                     max;            /* Max number of elements */
 207 };
 208
 209 struct iscsi_session {
 210         /*
 211          * Syncs up the scsi eh thread with the iscsi eh thread when sending
 212          * task management functions. This must be taken before the session
 213          * and recv lock.
 214          */
 215         struct mutex            eh_mutex;
 216
 217         /* iSCSI session-wide sequencing */
 218         uint32_t                cmdsn;
 219         uint32_t                exp_cmdsn;
 220         uint32_t                max_cmdsn;
 221
 222         /* This tracks the reqs queued into the initiator */
 223         uint32_t                queued_cmdsn;
 224
 225         /* configuration */
 226         int                     initial_r2t_en;
 227         unsigned                max_r2t;
 228         int                     imm_data_en;
 229         unsigned                first_burst;
 230         unsigned                max_burst;
 231         int                     time2wait;
 232         int                     time2retain;
 233         int                     pdu_inorder_en;
 234         int                     dataseq_inorder_en;
 235         int                     erl;
 236         int                     fast_abort;
 237         int                     tpgt;
 238         char                    *username;
 239         char                    *username_in;
 240         char                    *password;
 241         char                    *password_in;
 242         char                    *targetname;
 243         char                    *initiatorname;
 244         /* hw address or netdev iscsi connection is bound to */
 245         char                    *hwaddress;
 246         char                    *netdev;
 247         /* control data */
 248         struct iscsi_transport  *tt;
 249         struct Scsi_Host        *host;
 250         struct iscsi_conn       *leadconn;      /* leading connection */
 251         spinlock_t              lock;           /* protects session state, *
 252                                                  * sequence numbers,       *
 253                                                  * session resources:      *
 254                                                  * - cmdpool,              *
 255                                                  * - mgmtpool,             *
 256                                                  * - r2tpool               */
 257         int                     state;          /* session state           */
 258         int                     age;            /* counts session re-opens */
 259
 260         int                     cmds_max;       /* size of cmds array */
 261         struct iscsi_cmd_task   **cmds;         /* Original Cmds arr */
 262         struct iscsi_queue      cmdpool;        /* PDU's pool */
 263         int                     mgmtpool_max;   /* size of mgmt array */
 264         struct iscsi_mgmt_task  **mgmt_cmds;    /* Original mgmt arr */
 265         struct iscsi_queue      mgmtpool;       /* Mgmt PDU's pool */
 266 };
 267
 268 /*
 269  * scsi host template
 270  */
 271 extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
 272 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
 273 extern int iscsi_eh_host_reset(struct scsi_cmnd *sc);
 274 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
 275 extern int iscsi_queuecommand(struct scsi_cmnd *sc,
 276                               void (*done)(struct scsi_cmnd *));
 277
 278
 279 /*
 280  * iSCSI host helpers.
 281  */
 282 extern int iscsi_host_set_param(struct Scsi_Host *shost,
 283                                 enum iscsi_host_param param, char *buf,
 284                                 int buflen);
 285 extern int iscsi_host_get_param(struct Scsi_Host *shost,
 286                                 enum iscsi_host_param param, char *buf);
 287
 288 /*
 289  * session management
 290  */
 291 extern struct iscsi_cls_session *
 292 iscsi_session_setup(struct iscsi_transport *, struct scsi_transport_template *,
 293                     uint16_t, uint16_t, int, int, uint32_t, uint32_t *);
 294 extern void iscsi_session_teardown(struct iscsi_cls_session *);
 295 extern struct iscsi_session *class_to_transport_session(struct iscsi_cls_session *);
 296 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
 297 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
 298                            enum iscsi_param param, char *buf, int buflen);
 299 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
 300                                    enum iscsi_param param, char *buf);
 301
 302 #define session_to_cls(_sess) \
 303         hostdata_session(_sess->host->hostdata)
 304
 305 /*
 306  * connection management
 307  */
 308 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
 309                                                uint32_t);
 310 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
 311 extern int iscsi_conn_start(struct iscsi_cls_conn *);
 312 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
 313 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
 314                            int);
 315 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
 316 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
 317                                 enum iscsi_param param, char *buf);
 318
 319 /*
 320  * pdu and task processing
 321  */
 322 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
 323 extern void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *,
 324                                         struct iscsi_data *hdr);
 325 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
 326                                 char *, uint32_t);
 327 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 328                               char *, int);
 329 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 330                                 char *, int);
 331 extern int iscsi_verify_itt(struct iscsi_conn *, struct iscsi_hdr *,
 332                             uint32_t *);
 333 extern void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask);
 334
 335 /*
 336  * generic helpers
 337  */
 338 extern void iscsi_pool_free(struct iscsi_queue *, void **);
 339 extern int iscsi_pool_init(struct iscsi_queue *, int, void ***, int);
 340
 341 #endif