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 #define TMABORT_INITIAL                 0x0
  61 #define TMABORT_SUCCESS                 0x1
  62 #define TMABORT_FAILED                  0x2
  63 #define TMABORT_TIMEDOUT                0x3
  64 #define TMABORT_NOT_FOUND               0x4
  65
  66 /* Connection suspend "bit" */
  67 #define ISCSI_SUSPEND_BIT               1
  68
  69 #define ISCSI_ITT_MASK                  (0xfff)
  70 #define ISCSI_CID_SHIFT                 12
  71 #define ISCSI_CID_MASK                  (0xffff << ISCSI_CID_SHIFT)
  72 #define ISCSI_AGE_SHIFT                 28
  73 #define ISCSI_AGE_MASK                  (0xf << ISCSI_AGE_SHIFT)
  74
  75 struct iscsi_mgmt_task {
  76         /*
  77          * Becuae LLDs allocate their hdr differently, this is a pointer to
  78          * that storage. It must be setup at session creation time.
  79          */
  80         struct iscsi_hdr        *hdr;
  81         char                    *data;          /* mgmt payload */
  82         unsigned                data_count;     /* counts data to be sent */
  83         uint32_t                itt;            /* this ITT */
  84         void                    *dd_data;       /* driver/transport data */
  85         struct list_head        running;
  86 };
  87
  88 enum {
  89         ISCSI_TASK_COMPLETED,
  90         ISCSI_TASK_PENDING,
  91         ISCSI_TASK_RUNNING,
  92         ISCSI_TASK_ABORTING,
  93 };
  94
  95 struct iscsi_cmd_task {
  96         /*
  97          * Becuae LLDs allocate their hdr differently, this is a pointer to
  98          * that storage. It must be setup at session creation time.
  99          */
 100         struct iscsi_cmd        *hdr;
 101         int                     itt;            /* this ITT */
 102
 103         uint32_t                unsol_datasn;
 104         unsigned                imm_count;      /* imm-data (bytes)   */
 105         unsigned                unsol_count;    /* unsolicited (bytes)*/
 106         /* offset in unsolicited stream (bytes); */
 107         unsigned                unsol_offset;
 108         unsigned                data_count;     /* remaining Data-Out */
 109         struct scsi_cmnd        *sc;            /* associated SCSI cmd*/
 110         struct iscsi_conn       *conn;          /* used connection    */
 111         struct iscsi_mgmt_task  *mtask;         /* tmf mtask in progr */
 112
 113         /* state set/tested under session->lock */
 114         int                     state;
 115         atomic_t                refcount;
 116         struct list_head        running;        /* running cmd list */
 117         void                    *dd_data;       /* driver/transport data */
 118 };
 119
 120 struct iscsi_conn {
 121         struct iscsi_cls_conn   *cls_conn;      /* ptr to class connection */
 122         void                    *dd_data;       /* iscsi_transport data */
 123         struct iscsi_session    *session;       /* parent session */
 124         /*
 125          * LLDs should set this lock. It protects the transport recv
 126          * code
 127          */
 128         rwlock_t                *recv_lock;
 129         /*
 130          * conn_stop() flag: stop to recover, stop to terminate
 131          */
 132         int                     stop_stage;
 133
 134         /* iSCSI connection-wide sequencing */
 135         uint32_t                exp_statsn;
 136
 137         /* control data */
 138         int                     id;             /* CID */
 139         int                     c_stage;        /* connection state */
 140         /*
 141          * Preallocated buffer for pdus that have data but do not
 142          * originate from scsi-ml. We never have two pdus using the
 143          * buffer at the same time. It is only allocated to
 144          * the default max recv size because the pdus we support
 145          * should always fit in this buffer
 146          */
 147         char                    *data;
 148         struct iscsi_mgmt_task  *login_mtask;   /* mtask used for login/text */
 149         struct iscsi_mgmt_task  *mtask;         /* xmit mtask in progress */
 150         struct iscsi_cmd_task   *ctask;         /* xmit ctask in progress */
 151
 152         /* xmit */
 153         struct kfifo            *mgmtqueue;     /* mgmt (control) xmit queue */
 154         struct list_head        mgmt_run_list;  /* list of control tasks */
 155         struct list_head        xmitqueue;      /* data-path cmd queue */
 156         struct list_head        run_list;       /* list of cmds in progress */
 157         struct work_struct      xmitwork;       /* per-conn. xmit workqueue */
 158         unsigned long           suspend_tx;     /* suspend Tx */
 159         unsigned long           suspend_rx;     /* suspend Rx */
 160
 161         /* abort */
 162         wait_queue_head_t       ehwait;         /* used in eh_abort() */
 163         struct iscsi_tm         tmhdr;
 164         struct timer_list       tmabort_timer;
 165         int                     tmabort_state;  /* see TMABORT_INITIAL, etc.*/
 166
 167         /* negotiated params */
 168         unsigned                max_recv_dlength; /* initiator_max_recv_dsl*/
 169         unsigned                max_xmit_dlength; /* target_max_recv_dsl */
 170         int                     hdrdgst_en;
 171         int                     datadgst_en;
 172         int                     ifmarker_en;
 173         int                     ofmarker_en;
 174         /* values userspace uses to id a conn */
 175         int                     persistent_port;
 176         char                    *persistent_address;
 177
 178         /* MIB-statistics */
 179         uint64_t                txdata_octets;
 180         uint64_t                rxdata_octets;
 181         uint32_t                scsicmd_pdus_cnt;
 182         uint32_t                dataout_pdus_cnt;
 183         uint32_t                scsirsp_pdus_cnt;
 184         uint32_t                datain_pdus_cnt;
 185         uint32_t                r2t_pdus_cnt;
 186         uint32_t                tmfcmd_pdus_cnt;
 187         int32_t                 tmfrsp_pdus_cnt;
 188
 189         /* custom statistics */
 190         uint32_t                eh_abort_cnt;
 191 };
 192
 193 struct iscsi_queue {
 194         struct kfifo            *queue;         /* FIFO Queue */
 195         void                    **pool;         /* Pool of elements */
 196         int                     max;            /* Max number of elements */
 197 };
 198
 199 struct iscsi_session {
 200         /* iSCSI session-wide sequencing */
 201         uint32_t                cmdsn;
 202         uint32_t                exp_cmdsn;
 203         uint32_t                max_cmdsn;
 204
 205         /* configuration */
 206         int                     initial_r2t_en;
 207         unsigned                max_r2t;
 208         int                     imm_data_en;
 209         unsigned                first_burst;
 210         unsigned                max_burst;
 211         int                     time2wait;
 212         int                     time2retain;
 213         int                     pdu_inorder_en;
 214         int                     dataseq_inorder_en;
 215         int                     erl;
 216         int                     tpgt;
 217         char                    *username;
 218         char                    *username_in;
 219         char                    *password;
 220         char                    *password_in;
 221         char                    *targetname;
 222         char                    *initiatorname;
 223         /* hw address being used for iscsi connection */
 224         char                    *hwaddress;
 225         /* control data */
 226         struct iscsi_transport  *tt;
 227         struct Scsi_Host        *host;
 228         struct iscsi_conn       *leadconn;      /* leading connection */
 229         spinlock_t              lock;           /* protects session state, *
 230                                                  * sequence numbers,       *
 231                                                  * session resources:      *
 232                                                  * - cmdpool,              *
 233                                                  * - mgmtpool,             *
 234                                                  * - r2tpool               */
 235         int                     state;          /* session state           */
 236         int                     age;            /* counts session re-opens */
 237
 238         int                     cmds_max;       /* size of cmds array */
 239         struct iscsi_cmd_task   **cmds;         /* Original Cmds arr */
 240         struct iscsi_queue      cmdpool;        /* PDU's pool */
 241         int                     mgmtpool_max;   /* size of mgmt array */
 242         struct iscsi_mgmt_task  **mgmt_cmds;    /* Original mgmt arr */
 243         struct iscsi_queue      mgmtpool;       /* Mgmt PDU's pool */
 244 };
 245
 246 /*
 247  * scsi host template
 248  */
 249 extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
 250 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
 251 extern int iscsi_eh_host_reset(struct scsi_cmnd *sc);
 252 extern int iscsi_queuecommand(struct scsi_cmnd *sc,
 253                               void (*done)(struct scsi_cmnd *));
 254
 255
 256 /*
 257  * iSCSI host helpers.
 258  */
 259 extern int iscsi_host_set_param(struct Scsi_Host *shost,
 260                                 enum iscsi_host_param param, char *buf,
 261                                 int buflen);
 262 extern int iscsi_host_get_param(struct Scsi_Host *shost,
 263                                 enum iscsi_host_param param, char *buf);
 264
 265 /*
 266  * session management
 267  */
 268 extern struct iscsi_cls_session *
 269 iscsi_session_setup(struct iscsi_transport *, struct scsi_transport_template *,
 270                     uint16_t, uint16_t, int, int, uint32_t, uint32_t *);
 271 extern void iscsi_session_teardown(struct iscsi_cls_session *);
 272 extern struct iscsi_session *class_to_transport_session(struct iscsi_cls_session *);
 273 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
 274 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
 275                            enum iscsi_param param, char *buf, int buflen);
 276 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
 277                                    enum iscsi_param param, char *buf);
 278
 279 #define session_to_cls(_sess) \
 280         hostdata_session(_sess->host->hostdata)
 281
 282 /*
 283  * connection management
 284  */
 285 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
 286                                                uint32_t);
 287 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
 288 extern int iscsi_conn_start(struct iscsi_cls_conn *);
 289 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
 290 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
 291                            int);
 292 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
 293 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
 294                                 enum iscsi_param param, char *buf);
 295
 296 /*
 297  * pdu and task processing
 298  */
 299 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
 300 extern void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *,
 301                                         struct iscsi_data *hdr);
 302 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
 303                                 char *, uint32_t);
 304 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 305                               char *, int);
 306 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
 307                                 char *, int);
 308 extern int iscsi_verify_itt(struct iscsi_conn *, struct iscsi_hdr *,
 309                             uint32_t *);
 310
 311 /*
 312  * generic helpers
 313  */
 314 extern void iscsi_pool_free(struct iscsi_queue *, void **);
 315 extern int iscsi_pool_init(struct iscsi_queue *, int, void ***, int);
 316
 317 #endif