Pileus Git - ~andy/linux/blob - drivers/scsi/libiscsi.c

   1 /*
   2  * iSCSI lib functions
   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  * maintained by open-iscsi@googlegroups.com
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  */
  24 #include <linux/types.h>
  25 #include <linux/kfifo.h>
  26 #include <linux/delay.h>
  27 #include <linux/log2.h>
  28 #include <asm/unaligned.h>
  29 #include <net/tcp.h>
  30 #include <scsi/scsi_cmnd.h>
  31 #include <scsi/scsi_device.h>
  32 #include <scsi/scsi_eh.h>
  33 #include <scsi/scsi_tcq.h>
  34 #include <scsi/scsi_host.h>
  35 #include <scsi/scsi.h>
  36 #include <scsi/iscsi_proto.h>
  37 #include <scsi/scsi_transport.h>
  38 #include <scsi/scsi_transport_iscsi.h>
  39 #include <scsi/libiscsi.h>
  40
  41 struct iscsi_session *
  42 class_to_transport_session(struct iscsi_cls_session *cls_session)
  43 {
  44         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
  45         return iscsi_hostdata(shost->hostdata);
  46 }
  47 EXPORT_SYMBOL_GPL(class_to_transport_session);
  48
  49 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
  50 #define SNA32_CHECK 2147483648UL
  51
  52 static int iscsi_sna_lt(u32 n1, u32 n2)
  53 {
  54         return n1 != n2 && ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
  55                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
  56 }
  57
  58 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
  59 static int iscsi_sna_lte(u32 n1, u32 n2)
  60 {
  61         return n1 == n2 || ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
  62                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
  63 }
  64
  65 void
  66 iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
  67 {
  68         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
  69         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
  70
  71         /*
  72          * standard specifies this check for when to update expected and
  73          * max sequence numbers
  74          */
  75         if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
  76                 return;
  77
  78         if (exp_cmdsn != session->exp_cmdsn &&
  79             !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
  80                 session->exp_cmdsn = exp_cmdsn;
  81
  82         if (max_cmdsn != session->max_cmdsn &&
  83             !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
  84                 session->max_cmdsn = max_cmdsn;
  85                 /*
  86                  * if the window closed with IO queued, then kick the
  87                  * xmit thread
  88                  */
  89                 if (!list_empty(&session->leadconn->xmitqueue) ||
  90                     !list_empty(&session->leadconn->mgmtqueue))
  91                         scsi_queue_work(session->host,
  92                                         &session->leadconn->xmitwork);
  93         }
  94 }
  95 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
  96
  97 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
  98                                    struct iscsi_data *hdr)
  99 {
 100         struct iscsi_conn *conn = ctask->conn;
 101
 102         memset(hdr, 0, sizeof(struct iscsi_data));
 103         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
 104         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
 105         ctask->unsol_datasn++;
 106         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
 107         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
 108
 109         hdr->itt = ctask->hdr->itt;
 110         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 111         hdr->offset = cpu_to_be32(ctask->unsol_offset);
 112
 113         if (ctask->unsol_count > conn->max_xmit_dlength) {
 114                 hton24(hdr->dlength, conn->max_xmit_dlength);
 115                 ctask->data_count = conn->max_xmit_dlength;
 116                 ctask->unsol_offset += ctask->data_count;
 117                 hdr->flags = 0;
 118         } else {
 119                 hton24(hdr->dlength, ctask->unsol_count);
 120                 ctask->data_count = ctask->unsol_count;
 121                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
 122         }
 123 }
 124 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
 125
 126 static int iscsi_add_hdr(struct iscsi_cmd_task *ctask, unsigned len)
 127 {
 128         unsigned exp_len = ctask->hdr_len + len;
 129
 130         if (exp_len > ctask->hdr_max) {
 131                 WARN_ON(1);
 132                 return -EINVAL;
 133         }
 134
 135         WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
 136         ctask->hdr_len = exp_len;
 137         return 0;
 138 }
 139
 140 /**
 141  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
 142  * @ctask: iscsi cmd task
 143  *
 144  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
 145  * fields like dlength or final based on how much data it sends
 146  */
 147 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
 148 {
 149         struct iscsi_conn *conn = ctask->conn;
 150         struct iscsi_session *session = conn->session;
 151         struct iscsi_cmd *hdr = ctask->hdr;
 152         struct scsi_cmnd *sc = ctask->sc;
 153         unsigned hdrlength;
 154         int rc;
 155
 156         ctask->hdr_len = 0;
 157         rc = iscsi_add_hdr(ctask, sizeof(*hdr));
 158         if (rc)
 159                 return rc;
 160         hdr->opcode = ISCSI_OP_SCSI_CMD;
 161         hdr->flags = ISCSI_ATTR_SIMPLE;
 162         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
 163         hdr->itt = build_itt(ctask->itt, conn->id, session->age);
 164         hdr->data_length = cpu_to_be32(scsi_bufflen(sc));
 165         hdr->cmdsn = cpu_to_be32(session->cmdsn);
 166         session->cmdsn++;
 167         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 168         memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
 169         if (sc->cmd_len < MAX_COMMAND_SIZE)
 170                 memset(&hdr->cdb[sc->cmd_len], 0,
 171                         MAX_COMMAND_SIZE - sc->cmd_len);
 172
 173         ctask->imm_count = 0;
 174         if (sc->sc_data_direction == DMA_TO_DEVICE) {
 175                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 176                 /*
 177                  * Write counters:
 178                  *
 179                  *      imm_count       bytes to be sent right after
 180                  *                      SCSI PDU Header
 181                  *
 182                  *      unsol_count     bytes(as Data-Out) to be sent
 183                  *                      without R2T ack right after
 184                  *                      immediate data
 185                  *
 186                  *      r2t_data_count  bytes to be sent via R2T ack's
 187                  *
 188                  *      pad_count       bytes to be sent as zero-padding
 189                  */
 190                 ctask->unsol_count = 0;
 191                 ctask->unsol_offset = 0;
 192                 ctask->unsol_datasn = 0;
 193
 194                 if (session->imm_data_en) {
 195                         if (scsi_bufflen(sc) >= session->first_burst)
 196                                 ctask->imm_count = min(session->first_burst,
 197                                                         conn->max_xmit_dlength);
 198                         else
 199                                 ctask->imm_count = min(scsi_bufflen(sc),
 200                                                         conn->max_xmit_dlength);
 201                         hton24(hdr->dlength, ctask->imm_count);
 202                 } else
 203                         zero_data(hdr->dlength);
 204
 205                 if (!session->initial_r2t_en) {
 206                         ctask->unsol_count = min((session->first_burst),
 207                                 (scsi_bufflen(sc))) - ctask->imm_count;
 208                         ctask->unsol_offset = ctask->imm_count;
 209                 }
 210
 211                 if (!ctask->unsol_count)
 212                         /* No unsolicit Data-Out's */
 213                         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 214         } else {
 215                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 216                 zero_data(hdr->dlength);
 217
 218                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
 219                         hdr->flags |= ISCSI_FLAG_CMD_READ;
 220         }
 221
 222         /* calculate size of additional header segments (AHSs) */
 223         hdrlength = ctask->hdr_len - sizeof(*hdr);
 224
 225         WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
 226         hdrlength /= ISCSI_PAD_LEN;
 227
 228         WARN_ON(hdrlength >= 256);
 229         hdr->hlength = hdrlength & 0xFF;
 230
 231         if (conn->session->tt->init_cmd_task(conn->ctask))
 232                 return EIO;
 233
 234         conn->scsicmd_pdus_cnt++;
 235         debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x len %d "
 236                 "cmdsn %d win %d]\n",
 237                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
 238                 conn->id, sc, sc->cmnd[0], ctask->itt, scsi_bufflen(sc),
 239                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 240         return 0;
 241 }
 242
 243 /**
 244  * iscsi_complete_command - return command back to scsi-ml
 245  * @ctask: iscsi cmd task
 246  *
 247  * Must be called with session lock.
 248  * This function returns the scsi command to scsi-ml and returns
 249  * the cmd task to the pool of available cmd tasks.
 250  */
 251 static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
 252 {
 253         struct iscsi_conn *conn = ctask->conn;
 254         struct iscsi_session *session = conn->session;
 255         struct scsi_cmnd *sc = ctask->sc;
 256
 257         ctask->state = ISCSI_TASK_COMPLETED;
 258         ctask->sc = NULL;
 259         /* SCSI eh reuses commands to verify us */
 260         sc->SCp.ptr = NULL;
 261         if (conn->ctask == ctask)
 262                 conn->ctask = NULL;
 263         list_del_init(&ctask->running);
 264         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
 265         sc->scsi_done(sc);
 266 }
 267
 268 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
 269 {
 270         atomic_inc(&ctask->refcount);
 271 }
 272
 273 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
 274 {
 275         if (atomic_dec_and_test(&ctask->refcount))
 276                 iscsi_complete_command(ctask);
 277 }
 278
 279 /*
 280  * session lock must be held
 281  */
 282 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
 283                          int err)
 284 {
 285         struct scsi_cmnd *sc;
 286
 287         sc = ctask->sc;
 288         if (!sc)
 289                 return;
 290
 291         if (ctask->state == ISCSI_TASK_PENDING)
 292                 /*
 293                  * cmd never made it to the xmit thread, so we should not count
 294                  * the cmd in the sequencing
 295                  */
 296                 conn->session->queued_cmdsn--;
 297         else
 298                 conn->session->tt->cleanup_cmd_task(conn, ctask);
 299
 300         sc->result = err;
 301         scsi_set_resid(sc, scsi_bufflen(sc));
 302         if (conn->ctask == ctask)
 303                 conn->ctask = NULL;
 304         /* release ref from queuecommand */
 305         __iscsi_put_ctask(ctask);
 306 }
 307
 308 /**
 309  * iscsi_free_mgmt_task - return mgmt task back to pool
 310  * @conn: iscsi connection
 311  * @mtask: mtask
 312  *
 313  * Must be called with session lock.
 314  */
 315 void iscsi_free_mgmt_task(struct iscsi_conn *conn,
 316                           struct iscsi_mgmt_task *mtask)
 317 {
 318         list_del_init(&mtask->running);
 319         if (conn->login_mtask == mtask)
 320                 return;
 321
 322         if (conn->ping_mtask == mtask)
 323                 conn->ping_mtask = NULL;
 324         __kfifo_put(conn->session->mgmtpool.queue,
 325                     (void*)&mtask, sizeof(void*));
 326 }
 327 EXPORT_SYMBOL_GPL(iscsi_free_mgmt_task);
 328
 329 static struct iscsi_mgmt_task *
 330 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 331                       char *data, uint32_t data_size)
 332 {
 333         struct iscsi_session *session = conn->session;
 334         struct iscsi_mgmt_task *mtask;
 335
 336         if (session->state == ISCSI_STATE_TERMINATE)
 337                 return NULL;
 338
 339         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
 340             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 341                 /*
 342                  * Login and Text are sent serially, in
 343                  * request-followed-by-response sequence.
 344                  * Same mtask can be used. Same ITT must be used.
 345                  * Note that login_mtask is preallocated at conn_create().
 346                  */
 347                 mtask = conn->login_mtask;
 348         else {
 349                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 350                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 351
 352                 if (!__kfifo_get(session->mgmtpool.queue,
 353                                  (void*)&mtask, sizeof(void*)))
 354                         return NULL;
 355         }
 356
 357         if (data_size) {
 358                 memcpy(mtask->data, data, data_size);
 359                 mtask->data_count = data_size;
 360         } else
 361                 mtask->data_count = 0;
 362
 363         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
 364         INIT_LIST_HEAD(&mtask->running);
 365         list_add_tail(&mtask->running, &conn->mgmtqueue);
 366         return mtask;
 367 }
 368
 369 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 370                         char *data, uint32_t data_size)
 371 {
 372         struct iscsi_conn *conn = cls_conn->dd_data;
 373         struct iscsi_session *session = conn->session;
 374         int err = 0;
 375
 376         spin_lock_bh(&session->lock);
 377         if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
 378                 err = -EPERM;
 379         spin_unlock_bh(&session->lock);
 380         scsi_queue_work(session->host, &conn->xmitwork);
 381         return err;
 382 }
 383 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 384
 385 /**
 386  * iscsi_cmd_rsp - SCSI Command Response processing
 387  * @conn: iscsi connection
 388  * @hdr: iscsi header
 389  * @ctask: scsi command task
 390  * @data: cmd data buffer
 391  * @datalen: len of buffer
 392  *
 393  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 394  * then completes the command and task.
 395  **/
 396 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 397                                struct iscsi_cmd_task *ctask, char *data,
 398                                int datalen)
 399 {
 400         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
 401         struct iscsi_session *session = conn->session;
 402         struct scsi_cmnd *sc = ctask->sc;
 403
 404         iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
 405         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 406
 407         sc->result = (DID_OK << 16) | rhdr->cmd_status;
 408
 409         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 410                 sc->result = DID_ERROR << 16;
 411                 goto out;
 412         }
 413
 414         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 415                 uint16_t senselen;
 416
 417                 if (datalen < 2) {
 418 invalid_datalen:
 419                         printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
 420                                "invalid data buffer size of %d\n", datalen);
 421                         sc->result = DID_BAD_TARGET << 16;
 422                         goto out;
 423                 }
 424
 425                 senselen = be16_to_cpu(get_unaligned((__be16 *) data));
 426                 if (datalen < senselen)
 427                         goto invalid_datalen;
 428
 429                 memcpy(sc->sense_buffer, data + 2,
 430                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 431                 debug_scsi("copied %d bytes of sense\n",
 432                            min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 433         }
 434
 435         if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
 436                            ISCSI_FLAG_CMD_OVERFLOW)) {
 437                 int res_count = be32_to_cpu(rhdr->residual_count);
 438
 439                 if (res_count > 0 &&
 440                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 441                      res_count <= scsi_bufflen(sc)))
 442                         scsi_set_resid(sc, res_count);
 443                 else
 444                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 445         } else if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
 446                                   ISCSI_FLAG_CMD_BIDI_OVERFLOW))
 447                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 448
 449 out:
 450         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
 451                    (long)sc, sc->result, ctask->itt);
 452         conn->scsirsp_pdus_cnt++;
 453
 454         __iscsi_put_ctask(ctask);
 455 }
 456
 457 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 458 {
 459         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 460
 461         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 462         conn->tmfrsp_pdus_cnt++;
 463
 464         if (conn->tmf_state != TMF_QUEUED)
 465                 return;
 466
 467         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 468                 conn->tmf_state = TMF_SUCCESS;
 469         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 470                 conn->tmf_state = TMF_NOT_FOUND;
 471         else
 472                 conn->tmf_state = TMF_FAILED;
 473         wake_up(&conn->ehwait);
 474 }
 475
 476 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
 477 {
 478         struct iscsi_nopout hdr;
 479         struct iscsi_mgmt_task *mtask;
 480
 481         if (!rhdr && conn->ping_mtask)
 482                 return;
 483
 484         memset(&hdr, 0, sizeof(struct iscsi_nopout));
 485         hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
 486         hdr.flags = ISCSI_FLAG_CMD_FINAL;
 487
 488         if (rhdr) {
 489                 memcpy(hdr.lun, rhdr->lun, 8);
 490                 hdr.ttt = rhdr->ttt;
 491                 hdr.itt = RESERVED_ITT;
 492         } else
 493                 hdr.ttt = RESERVED_ITT;
 494
 495         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
 496         if (!mtask) {
 497                 printk(KERN_ERR "Could not send nopout\n");
 498                 return;
 499         }
 500
 501         /* only track our nops */
 502         if (!rhdr) {
 503                 conn->ping_mtask = mtask;
 504                 conn->last_ping = jiffies;
 505         }
 506         scsi_queue_work(conn->session->host, &conn->xmitwork);
 507 }
 508
 509 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 510                                char *data, int datalen)
 511 {
 512         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
 513         struct iscsi_hdr rejected_pdu;
 514         uint32_t itt;
 515
 516         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
 517
 518         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
 519                 if (ntoh24(reject->dlength) > datalen)
 520                         return ISCSI_ERR_PROTO;
 521
 522                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
 523                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
 524                         itt = get_itt(rejected_pdu.itt);
 525                         printk(KERN_ERR "itt 0x%x had pdu (op 0x%x) rejected "
 526                                 "due to DataDigest error.\n", itt,
 527                                 rejected_pdu.opcode);
 528                 }
 529         }
 530         return 0;
 531 }
 532
 533 /**
 534  * __iscsi_complete_pdu - complete pdu
 535  * @conn: iscsi conn
 536  * @hdr: iscsi header
 537  * @data: data buffer
 538  * @datalen: len of data buffer
 539  *
 540  * Completes pdu processing by freeing any resources allocated at
 541  * queuecommand or send generic. session lock must be held and verify
 542  * itt must have been called.
 543  */
 544 static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 545                                 char *data, int datalen)
 546 {
 547         struct iscsi_session *session = conn->session;
 548         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
 549         struct iscsi_cmd_task *ctask;
 550         struct iscsi_mgmt_task *mtask;
 551         uint32_t itt;
 552
 553         conn->last_recv = jiffies;
 554         if (hdr->itt != RESERVED_ITT)
 555                 itt = get_itt(hdr->itt);
 556         else
 557                 itt = ~0U;
 558
 559         if (itt < session->cmds_max) {
 560                 ctask = session->cmds[itt];
 561
 562                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 563                            opcode, conn->id, ctask->itt, datalen);
 564
 565                 switch(opcode) {
 566                 case ISCSI_OP_SCSI_CMD_RSP:
 567                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 568                         iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
 569                                            datalen);
 570                         break;
 571                 case ISCSI_OP_SCSI_DATA_IN:
 572                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 573                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
 574                                 conn->scsirsp_pdus_cnt++;
 575                                 __iscsi_put_ctask(ctask);
 576                         }
 577                         break;
 578                 case ISCSI_OP_R2T:
 579                         /* LLD handles this for now */
 580                         break;
 581                 default:
 582                         rc = ISCSI_ERR_BAD_OPCODE;
 583                         break;
 584                 }
 585         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
 586                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
 587                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
 588
 589                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 590                            opcode, conn->id, mtask->itt, datalen);
 591
 592                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 593                 switch(opcode) {
 594                 case ISCSI_OP_LOGOUT_RSP:
 595                         if (datalen) {
 596                                 rc = ISCSI_ERR_PROTO;
 597                                 break;
 598                         }
 599                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 600                         /* fall through */
 601                 case ISCSI_OP_LOGIN_RSP:
 602                 case ISCSI_OP_TEXT_RSP:
 603                         /*
 604                          * login related PDU's exp_statsn is handled in
 605                          * userspace
 606                          */
 607                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 608                                 rc = ISCSI_ERR_CONN_FAILED;
 609                         iscsi_free_mgmt_task(conn, mtask);
 610                         break;
 611                 case ISCSI_OP_SCSI_TMFUNC_RSP:
 612                         if (datalen) {
 613                                 rc = ISCSI_ERR_PROTO;
 614                                 break;
 615                         }
 616
 617                         iscsi_tmf_rsp(conn, hdr);
 618                         iscsi_free_mgmt_task(conn, mtask);
 619                         break;
 620                 case ISCSI_OP_NOOP_IN:
 621                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
 622                             datalen) {
 623                                 rc = ISCSI_ERR_PROTO;
 624                                 break;
 625                         }
 626                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 627
 628                         if (conn->ping_mtask != mtask) {
 629                                 /*
 630                                  * If this is not in response to one of our
 631                                  * nops then it must be from userspace.
 632                                  */
 633                                 if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
 634                                                    datalen))
 635                                         rc = ISCSI_ERR_CONN_FAILED;
 636                         }
 637                         iscsi_free_mgmt_task(conn, mtask);
 638                         break;
 639                 default:
 640                         rc = ISCSI_ERR_BAD_OPCODE;
 641                         break;
 642                 }
 643         } else if (itt == ~0U) {
 644                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 645
 646                 switch(opcode) {
 647                 case ISCSI_OP_NOOP_IN:
 648                         if (datalen) {
 649                                 rc = ISCSI_ERR_PROTO;
 650                                 break;
 651                         }
 652
 653                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
 654                                 break;
 655
 656                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
 657                         break;
 658                 case ISCSI_OP_REJECT:
 659                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
 660                         break;
 661                 case ISCSI_OP_ASYNC_EVENT:
 662                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 663                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 664                                 rc = ISCSI_ERR_CONN_FAILED;
 665                         break;
 666                 default:
 667                         rc = ISCSI_ERR_BAD_OPCODE;
 668                         break;
 669                 }
 670         } else
 671                 rc = ISCSI_ERR_BAD_ITT;
 672
 673         return rc;
 674 }
 675
 676 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 677                        char *data, int datalen)
 678 {
 679         int rc;
 680
 681         spin_lock(&conn->session->lock);
 682         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
 683         spin_unlock(&conn->session->lock);
 684         return rc;
 685 }
 686 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 687
 688 /* verify itt (itt encoding: age+cid+itt) */
 689 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 690                      uint32_t *ret_itt)
 691 {
 692         struct iscsi_session *session = conn->session;
 693         struct iscsi_cmd_task *ctask;
 694         uint32_t itt;
 695
 696         if (hdr->itt != RESERVED_ITT) {
 697                 if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
 698                     (session->age << ISCSI_AGE_SHIFT)) {
 699                         printk(KERN_ERR "iscsi: received itt %x expected "
 700                                 "session age (%x)\n", (__force u32)hdr->itt,
 701                                 session->age & ISCSI_AGE_MASK);
 702                         return ISCSI_ERR_BAD_ITT;
 703                 }
 704
 705                 if (((__force u32)hdr->itt & ISCSI_CID_MASK) !=
 706                     (conn->id << ISCSI_CID_SHIFT)) {
 707                         printk(KERN_ERR "iscsi: received itt %x, expected "
 708                                 "CID (%x)\n", (__force u32)hdr->itt, conn->id);
 709                         return ISCSI_ERR_BAD_ITT;
 710                 }
 711                 itt = get_itt(hdr->itt);
 712         } else
 713                 itt = ~0U;
 714
 715         if (itt < session->cmds_max) {
 716                 ctask = session->cmds[itt];
 717
 718                 if (!ctask->sc) {
 719                         printk(KERN_INFO "iscsi: dropping ctask with "
 720                                "itt 0x%x\n", ctask->itt);
 721                         /* force drop */
 722                         return ISCSI_ERR_NO_SCSI_CMD;
 723                 }
 724
 725                 if (ctask->sc->SCp.phase != session->age) {
 726                         printk(KERN_ERR "iscsi: ctask's session age %d, "
 727                                 "expected %d\n", ctask->sc->SCp.phase,
 728                                 session->age);
 729                         return ISCSI_ERR_SESSION_FAILED;
 730                 }
 731         }
 732
 733         *ret_itt = itt;
 734         return 0;
 735 }
 736 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 737
 738 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 739 {
 740         struct iscsi_session *session = conn->session;
 741         unsigned long flags;
 742
 743         spin_lock_irqsave(&session->lock, flags);
 744         if (session->state == ISCSI_STATE_FAILED) {
 745                 spin_unlock_irqrestore(&session->lock, flags);
 746                 return;
 747         }
 748
 749         if (conn->stop_stage == 0)
 750                 session->state = ISCSI_STATE_FAILED;
 751         spin_unlock_irqrestore(&session->lock, flags);
 752         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 753         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 754         iscsi_conn_error(conn->cls_conn, err);
 755 }
 756 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 757
 758 static void iscsi_prep_mtask(struct iscsi_conn *conn,
 759                              struct iscsi_mgmt_task *mtask)
 760 {
 761         struct iscsi_session *session = conn->session;
 762         struct iscsi_hdr *hdr = mtask->hdr;
 763         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 764
 765         if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
 766             hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 767                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 768         /*
 769          * pre-format CmdSN for outgoing PDU.
 770          */
 771         nop->cmdsn = cpu_to_be32(session->cmdsn);
 772         if (hdr->itt != RESERVED_ITT) {
 773                 hdr->itt = build_itt(mtask->itt, conn->id, session->age);
 774                 /*
 775                  * TODO: We always use immediate, so we never hit this.
 776                  * If we start to send tmfs or nops as non-immediate then
 777                  * we should start checking the cmdsn numbers for mgmt tasks.
 778                  */
 779                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 780                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
 781                         session->queued_cmdsn++;
 782                         session->cmdsn++;
 783                 }
 784         }
 785
 786         if (session->tt->init_mgmt_task)
 787                 session->tt->init_mgmt_task(conn, mtask);
 788
 789         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 790                    hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
 791                    mtask->data_count);
 792 }
 793
 794 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
 795 {
 796         struct iscsi_hdr *hdr = conn->mtask->hdr;
 797         int rc;
 798
 799         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
 800                 conn->session->state = ISCSI_STATE_LOGGING_OUT;
 801         spin_unlock_bh(&conn->session->lock);
 802
 803         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
 804         spin_lock_bh(&conn->session->lock);
 805         if (rc)
 806                 return rc;
 807
 808         /* done with this in-progress mtask */
 809         conn->mtask = NULL;
 810         return 0;
 811 }
 812
 813 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
 814 {
 815         struct iscsi_session *session = conn->session;
 816
 817         /*
 818          * Check for iSCSI window and take care of CmdSN wrap-around
 819          */
 820         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
 821                 debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
 822                            "CmdSN %u/%u\n", session->exp_cmdsn,
 823                            session->max_cmdsn, session->cmdsn,
 824                            session->queued_cmdsn);
 825                 return -ENOSPC;
 826         }
 827         return 0;
 828 }
 829
 830 static int iscsi_xmit_ctask(struct iscsi_conn *conn)
 831 {
 832         struct iscsi_cmd_task *ctask = conn->ctask;
 833         int rc;
 834
 835         __iscsi_get_ctask(ctask);
 836         spin_unlock_bh(&conn->session->lock);
 837         rc = conn->session->tt->xmit_cmd_task(conn, ctask);
 838         spin_lock_bh(&conn->session->lock);
 839         __iscsi_put_ctask(ctask);
 840         if (!rc)
 841                 /* done with this ctask */
 842                 conn->ctask = NULL;
 843         return rc;
 844 }
 845
 846 /**
 847  * iscsi_requeue_ctask - requeue ctask to run from session workqueue
 848  * @ctask: ctask to requeue
 849  *
 850  * LLDs that need to run a ctask from the session workqueue should call
 851  * this. The session lock must be held.
 852  */
 853 void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
 854 {
 855         struct iscsi_conn *conn = ctask->conn;
 856
 857         list_move_tail(&ctask->running, &conn->requeue);
 858         scsi_queue_work(conn->session->host, &conn->xmitwork);
 859 }
 860 EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
 861
 862 /**
 863  * iscsi_data_xmit - xmit any command into the scheduled connection
 864  * @conn: iscsi connection
 865  *
 866  * Notes:
 867  *      The function can return -EAGAIN in which case the caller must
 868  *      re-schedule it again later or recover. '0' return code means
 869  *      successful xmit.
 870  **/
 871 static int iscsi_data_xmit(struct iscsi_conn *conn)
 872 {
 873         int rc = 0;
 874
 875         spin_lock_bh(&conn->session->lock);
 876         if (unlikely(conn->suspend_tx)) {
 877                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 878                 spin_unlock_bh(&conn->session->lock);
 879                 return -ENODATA;
 880         }
 881
 882         if (conn->ctask) {
 883                 rc = iscsi_xmit_ctask(conn);
 884                 if (rc)
 885                         goto again;
 886         }
 887
 888         if (conn->mtask) {
 889                 rc = iscsi_xmit_mtask(conn);
 890                 if (rc)
 891                         goto again;
 892         }
 893
 894         /*
 895          * process mgmt pdus like nops before commands since we should
 896          * only have one nop-out as a ping from us and targets should not
 897          * overflow us with nop-ins
 898          */
 899 check_mgmt:
 900         while (!list_empty(&conn->mgmtqueue)) {
 901                 conn->mtask = list_entry(conn->mgmtqueue.next,
 902                                          struct iscsi_mgmt_task, running);
 903                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
 904                         iscsi_free_mgmt_task(conn, conn->mtask);
 905                         conn->mtask = NULL;
 906                         continue;
 907                 }
 908
 909                 iscsi_prep_mtask(conn, conn->mtask);
 910                 list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
 911                 rc = iscsi_xmit_mtask(conn);
 912                 if (rc)
 913                         goto again;
 914         }
 915
 916         /* process pending command queue */
 917         while (!list_empty(&conn->xmitqueue)) {
 918                 if (conn->tmf_state == TMF_QUEUED)
 919                         break;
 920
 921                 conn->ctask = list_entry(conn->xmitqueue.next,
 922                                          struct iscsi_cmd_task, running);
 923                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
 924                         fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
 925                         continue;
 926                 }
 927                 if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
 928                         fail_command(conn, conn->ctask, DID_ABORT << 16);
 929                         continue;
 930                 }
 931
 932                 conn->ctask->state = ISCSI_TASK_RUNNING;
 933                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
 934                 rc = iscsi_xmit_ctask(conn);
 935                 if (rc)
 936                         goto again;
 937                 /*
 938                  * we could continuously get new ctask requests so
 939                  * we need to check the mgmt queue for nops that need to
 940                  * be sent to aviod starvation
 941                  */
 942                 if (!list_empty(&conn->mgmtqueue))
 943                         goto check_mgmt;
 944         }
 945
 946         while (!list_empty(&conn->requeue)) {
 947                 if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
 948                         break;
 949
 950                 /*
 951                  * we always do fastlogout - conn stop code will clean up.
 952                  */
 953                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
 954                         break;
 955
 956                 conn->ctask = list_entry(conn->requeue.next,
 957                                          struct iscsi_cmd_task, running);
 958                 conn->ctask->state = ISCSI_TASK_RUNNING;
 959                 list_move_tail(conn->requeue.next, &conn->run_list);
 960                 rc = iscsi_xmit_ctask(conn);
 961                 if (rc)
 962                         goto again;
 963                 if (!list_empty(&conn->mgmtqueue))
 964                         goto check_mgmt;
 965         }
 966         spin_unlock_bh(&conn->session->lock);
 967         return -ENODATA;
 968
 969 again:
 970         if (unlikely(conn->suspend_tx))
 971                 rc = -ENODATA;
 972         spin_unlock_bh(&conn->session->lock);
 973         return rc;
 974 }
 975
 976 static void iscsi_xmitworker(struct work_struct *work)
 977 {
 978         struct iscsi_conn *conn =
 979                 container_of(work, struct iscsi_conn, xmitwork);
 980         int rc;
 981         /*
 982          * serialize Xmit worker on a per-connection basis.
 983          */
 984         do {
 985                 rc = iscsi_data_xmit(conn);
 986         } while (rc >= 0 || rc == -EAGAIN);
 987 }
 988
 989 enum {
 990         FAILURE_BAD_HOST = 1,
 991         FAILURE_SESSION_FAILED,
 992         FAILURE_SESSION_FREED,
 993         FAILURE_WINDOW_CLOSED,
 994         FAILURE_OOM,
 995         FAILURE_SESSION_TERMINATE,
 996         FAILURE_SESSION_IN_RECOVERY,
 997         FAILURE_SESSION_RECOVERY_TIMEOUT,
 998         FAILURE_SESSION_LOGGING_OUT,
 999         FAILURE_SESSION_NOT_READY,
1000 };
1001
1002 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
1003 {
1004         struct Scsi_Host *host;
1005         int reason = 0;
1006         struct iscsi_session *session;
1007         struct iscsi_conn *conn;
1008         struct iscsi_cmd_task *ctask = NULL;
1009
1010         sc->scsi_done = done;
1011         sc->result = 0;
1012         sc->SCp.ptr = NULL;
1013
1014         host = sc->device->host;
1015         spin_unlock(host->host_lock);
1016
1017         session = iscsi_hostdata(host->hostdata);
1018         spin_lock(&session->lock);
1019
1020         reason = iscsi_session_chkready(session_to_cls(session));
1021         if (reason) {
1022                 sc->result = reason;
1023                 goto fault;
1024         }
1025
1026         /*
1027          * ISCSI_STATE_FAILED is a temp. state. The recovery
1028          * code will decide what is best to do with command queued
1029          * during this time
1030          */
1031         if (session->state != ISCSI_STATE_LOGGED_IN &&
1032             session->state != ISCSI_STATE_FAILED) {
1033                 /*
1034                  * to handle the race between when we set the recovery state
1035                  * and block the session we requeue here (commands could
1036                  * be entering our queuecommand while a block is starting
1037                  * up because the block code is not locked)
1038                  */
1039                 switch (session->state) {
1040                 case ISCSI_STATE_IN_RECOVERY:
1041                         reason = FAILURE_SESSION_IN_RECOVERY;
1042                         sc->result = DID_IMM_RETRY << 16;
1043                         break;
1044                 case ISCSI_STATE_LOGGING_OUT:
1045                         reason = FAILURE_SESSION_LOGGING_OUT;
1046                         sc->result = DID_IMM_RETRY << 16;
1047                         break;
1048                 case ISCSI_STATE_RECOVERY_FAILED:
1049                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1050                         sc->result = DID_NO_CONNECT << 16;
1051                         break;
1052                 case ISCSI_STATE_TERMINATE:
1053                         reason = FAILURE_SESSION_TERMINATE;
1054                         sc->result = DID_NO_CONNECT << 16;
1055                         break;
1056                 default:
1057                         reason = FAILURE_SESSION_FREED;
1058                         sc->result = DID_NO_CONNECT << 16;
1059                 }
1060                 goto fault;
1061         }
1062
1063         conn = session->leadconn;
1064         if (!conn) {
1065                 reason = FAILURE_SESSION_FREED;
1066                 sc->result = DID_NO_CONNECT << 16;
1067                 goto fault;
1068         }
1069
1070         if (iscsi_check_cmdsn_window_closed(conn)) {
1071                 reason = FAILURE_WINDOW_CLOSED;
1072                 goto reject;
1073         }
1074
1075         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
1076                          sizeof(void*))) {
1077                 reason = FAILURE_OOM;
1078                 goto reject;
1079         }
1080         session->queued_cmdsn++;
1081
1082         sc->SCp.phase = session->age;
1083         sc->SCp.ptr = (char *)ctask;
1084
1085         atomic_set(&ctask->refcount, 1);
1086         ctask->state = ISCSI_TASK_PENDING;
1087         ctask->conn = conn;
1088         ctask->sc = sc;
1089         INIT_LIST_HEAD(&ctask->running);
1090
1091         list_add_tail(&ctask->running, &conn->xmitqueue);
1092         spin_unlock(&session->lock);
1093
1094         scsi_queue_work(host, &conn->xmitwork);
1095         spin_lock(host->host_lock);
1096         return 0;
1097
1098 reject:
1099         spin_unlock(&session->lock);
1100         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
1101         spin_lock(host->host_lock);
1102         return SCSI_MLQUEUE_HOST_BUSY;
1103
1104 fault:
1105         spin_unlock(&session->lock);
1106         debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
1107         scsi_set_resid(sc, scsi_bufflen(sc));
1108         sc->scsi_done(sc);
1109         spin_lock(host->host_lock);
1110         return 0;
1111 }
1112 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1113
1114 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
1115 {
1116         if (depth > ISCSI_MAX_CMD_PER_LUN)
1117                 depth = ISCSI_MAX_CMD_PER_LUN;
1118         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1119         return sdev->queue_depth;
1120 }
1121 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1122
1123 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
1124 {
1125         struct iscsi_session *session = class_to_transport_session(cls_session);
1126
1127         spin_lock_bh(&session->lock);
1128         if (session->state != ISCSI_STATE_LOGGED_IN) {
1129                 session->state = ISCSI_STATE_RECOVERY_FAILED;
1130                 if (session->leadconn)
1131                         wake_up(&session->leadconn->ehwait);
1132         }
1133         spin_unlock_bh(&session->lock);
1134 }
1135 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
1136
1137 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
1138 {
1139         struct Scsi_Host *host = sc->device->host;
1140         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1141         struct iscsi_conn *conn = session->leadconn;
1142
1143         mutex_lock(&session->eh_mutex);
1144         spin_lock_bh(&session->lock);
1145         if (session->state == ISCSI_STATE_TERMINATE) {
1146 failed:
1147                 debug_scsi("failing host reset: session terminated "
1148                            "[CID %d age %d]\n", conn->id, session->age);
1149                 spin_unlock_bh(&session->lock);
1150                 mutex_unlock(&session->eh_mutex);
1151                 return FAILED;
1152         }
1153
1154         spin_unlock_bh(&session->lock);
1155         mutex_unlock(&session->eh_mutex);
1156         /*
1157          * we drop the lock here but the leadconn cannot be destoyed while
1158          * we are in the scsi eh
1159          */
1160         iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1161
1162         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
1163         wait_event_interruptible(conn->ehwait,
1164                                  session->state == ISCSI_STATE_TERMINATE ||
1165                                  session->state == ISCSI_STATE_LOGGED_IN ||
1166                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
1167         if (signal_pending(current))
1168                 flush_signals(current);
1169
1170         mutex_lock(&session->eh_mutex);
1171         spin_lock_bh(&session->lock);
1172         if (session->state == ISCSI_STATE_LOGGED_IN)
1173                 printk(KERN_INFO "iscsi: host reset succeeded\n");
1174         else
1175                 goto failed;
1176         spin_unlock_bh(&session->lock);
1177         mutex_unlock(&session->eh_mutex);
1178         return SUCCESS;
1179 }
1180 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1181
1182 static void iscsi_tmf_timedout(unsigned long data)
1183 {
1184         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1185         struct iscsi_session *session = conn->session;
1186
1187         spin_lock(&session->lock);
1188         if (conn->tmf_state == TMF_QUEUED) {
1189                 conn->tmf_state = TMF_TIMEDOUT;
1190                 debug_scsi("tmf timedout\n");
1191                 /* unblock eh_abort() */
1192                 wake_up(&conn->ehwait);
1193         }
1194         spin_unlock(&session->lock);
1195 }
1196
1197 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1198                                    struct iscsi_tm *hdr, int age,
1199                                    int timeout)
1200 {
1201         struct iscsi_session *session = conn->session;
1202         struct iscsi_mgmt_task *mtask;
1203
1204         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1205                                       NULL, 0);
1206         if (!mtask) {
1207                 spin_unlock_bh(&session->lock);
1208                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1209                 spin_lock_bh(&session->lock);
1210                 debug_scsi("tmf exec failure\n");
1211                 return -EPERM;
1212         }
1213         conn->tmfcmd_pdus_cnt++;
1214         conn->tmf_timer.expires = timeout * HZ + jiffies;
1215         conn->tmf_timer.function = iscsi_tmf_timedout;
1216         conn->tmf_timer.data = (unsigned long)conn;
1217         add_timer(&conn->tmf_timer);
1218         debug_scsi("tmf set timeout\n");
1219
1220         spin_unlock_bh(&session->lock);
1221         mutex_unlock(&session->eh_mutex);
1222         scsi_queue_work(session->host, &conn->xmitwork);
1223
1224         /*
1225          * block eh thread until:
1226          *
1227          * 1) tmf response
1228          * 2) tmf timeout
1229          * 3) session is terminated or restarted or userspace has
1230          * given up on recovery
1231          */
1232         wait_event_interruptible(conn->ehwait, age != session->age ||
1233                                  session->state != ISCSI_STATE_LOGGED_IN ||
1234                                  conn->tmf_state != TMF_QUEUED);
1235         if (signal_pending(current))
1236                 flush_signals(current);
1237         del_timer_sync(&conn->tmf_timer);
1238
1239         mutex_lock(&session->eh_mutex);
1240         spin_lock_bh(&session->lock);
1241         /* if the session drops it will clean up the mtask */
1242         if (age != session->age ||
1243             session->state != ISCSI_STATE_LOGGED_IN)
1244                 return -ENOTCONN;
1245         return 0;
1246 }
1247
1248 /*
1249  * Fail commands. session lock held and recv side suspended and xmit
1250  * thread flushed
1251  */
1252 static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
1253                               int error)
1254 {
1255         struct iscsi_cmd_task *ctask, *tmp;
1256
1257         if (conn->ctask && (conn->ctask->sc->device->lun == lun || lun == -1))
1258                 conn->ctask = NULL;
1259
1260         /* flush pending */
1261         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1262                 if (lun == ctask->sc->device->lun || lun == -1) {
1263                         debug_scsi("failing pending sc %p itt 0x%x\n",
1264                                    ctask->sc, ctask->itt);
1265                         fail_command(conn, ctask, error << 16);
1266                 }
1267         }
1268
1269         list_for_each_entry_safe(ctask, tmp, &conn->requeue, running) {
1270                 if (lun == ctask->sc->device->lun || lun == -1) {
1271                         debug_scsi("failing requeued sc %p itt 0x%x\n",
1272                                    ctask->sc, ctask->itt);
1273                         fail_command(conn, ctask, error << 16);
1274                 }
1275         }
1276
1277         /* fail all other running */
1278         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1279                 if (lun == ctask->sc->device->lun || lun == -1) {
1280                         debug_scsi("failing in progress sc %p itt 0x%x\n",
1281                                    ctask->sc, ctask->itt);
1282                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1283                 }
1284         }
1285 }
1286
1287 static void iscsi_suspend_tx(struct iscsi_conn *conn)
1288 {
1289         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1290         scsi_flush_work(conn->session->host);
1291 }
1292
1293 static void iscsi_start_tx(struct iscsi_conn *conn)
1294 {
1295         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1296         scsi_queue_work(conn->session->host, &conn->xmitwork);
1297 }
1298
1299 static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
1300 {
1301         struct iscsi_cls_session *cls_session;
1302         struct iscsi_session *session;
1303         struct iscsi_conn *conn;
1304         enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
1305
1306         cls_session = starget_to_session(scsi_target(scmd->device));
1307         session = class_to_transport_session(cls_session);
1308
1309         debug_scsi("scsi cmd %p timedout\n", scmd);
1310
1311         spin_lock(&session->lock);
1312         if (session->state != ISCSI_STATE_LOGGED_IN) {
1313                 /*
1314                  * We are probably in the middle of iscsi recovery so let
1315                  * that complete and handle the error.
1316                  */
1317                 rc = EH_RESET_TIMER;
1318                 goto done;
1319         }
1320
1321         conn = session->leadconn;
1322         if (!conn) {
1323                 /* In the middle of shuting down */
1324                 rc = EH_RESET_TIMER;
1325                 goto done;
1326         }
1327
1328         if (!conn->recv_timeout && !conn->ping_timeout)
1329                 goto done;
1330         /*
1331          * if the ping timedout then we are in the middle of cleaning up
1332          * and can let the iscsi eh handle it
1333          */
1334         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1335                             (conn->ping_timeout * HZ), jiffies))
1336                 rc = EH_RESET_TIMER;
1337         /*
1338          * if we are about to check the transport then give the command
1339          * more time
1340          */
1341         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
1342                            jiffies))
1343                 rc = EH_RESET_TIMER;
1344         /* if in the middle of checking the transport then give us more time */
1345         if (conn->ping_mtask)
1346                 rc = EH_RESET_TIMER;
1347 done:
1348         spin_unlock(&session->lock);
1349         debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
1350         return rc;
1351 }
1352
1353 static void iscsi_check_transport_timeouts(unsigned long data)
1354 {
1355         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1356         struct iscsi_session *session = conn->session;
1357         unsigned long timeout, next_timeout = 0, last_recv;
1358
1359         spin_lock(&session->lock);
1360         if (session->state != ISCSI_STATE_LOGGED_IN)
1361                 goto done;
1362
1363         timeout = conn->recv_timeout;
1364         if (!timeout)
1365                 goto done;
1366
1367         timeout *= HZ;
1368         last_recv = conn->last_recv;
1369         if (time_before_eq(last_recv + timeout + (conn->ping_timeout * HZ),
1370                            jiffies)) {
1371                 printk(KERN_ERR "ping timeout of %d secs expired, "
1372                        "last rx %lu, last ping %lu, now %lu\n",
1373                        conn->ping_timeout, last_recv,
1374                        conn->last_ping, jiffies);
1375                 spin_unlock(&session->lock);
1376                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1377                 return;
1378         }
1379
1380         if (time_before_eq(last_recv + timeout, jiffies)) {
1381                 if (time_before_eq(conn->last_ping, last_recv)) {
1382                         /* send a ping to try to provoke some traffic */
1383                         debug_scsi("Sending nopout as ping on conn %p\n", conn);
1384                         iscsi_send_nopout(conn, NULL);
1385                 }
1386                 next_timeout = last_recv + timeout + (conn->ping_timeout * HZ);
1387         } else {
1388                 next_timeout = last_recv + timeout;
1389         }
1390
1391         if (next_timeout) {
1392                 debug_scsi("Setting next tmo %lu\n", next_timeout);
1393                 mod_timer(&conn->transport_timer, next_timeout);
1394         }
1395 done:
1396         spin_unlock(&session->lock);
1397 }
1398
1399 static void iscsi_prep_abort_task_pdu(struct iscsi_cmd_task *ctask,
1400                                       struct iscsi_tm *hdr)
1401 {
1402         memset(hdr, 0, sizeof(*hdr));
1403         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1404         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
1405         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1406         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1407         hdr->rtt = ctask->hdr->itt;
1408         hdr->refcmdsn = ctask->hdr->cmdsn;
1409 }
1410
1411 int iscsi_eh_abort(struct scsi_cmnd *sc)
1412 {
1413         struct Scsi_Host *host = sc->device->host;
1414         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1415         struct iscsi_conn *conn;
1416         struct iscsi_cmd_task *ctask;
1417         struct iscsi_tm *hdr;
1418         int rc, age;
1419
1420         mutex_lock(&session->eh_mutex);
1421         spin_lock_bh(&session->lock);
1422         /*
1423          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1424          * got the command.
1425          */
1426         if (!sc->SCp.ptr) {
1427                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1428                 spin_unlock_bh(&session->lock);
1429                 mutex_unlock(&session->eh_mutex);
1430                 return SUCCESS;
1431         }
1432
1433         /*
1434          * If we are not logged in or we have started a new session
1435          * then let the host reset code handle this
1436          */
1437         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
1438             sc->SCp.phase != session->age) {
1439                 spin_unlock_bh(&session->lock);
1440                 mutex_unlock(&session->eh_mutex);
1441                 return FAILED;
1442         }
1443
1444         conn = session->leadconn;
1445         conn->eh_abort_cnt++;
1446         age = session->age;
1447
1448         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1449         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1450
1451         /* ctask completed before time out */
1452         if (!ctask->sc) {
1453                 debug_scsi("sc completed while abort in progress\n");
1454                 goto success;
1455         }
1456
1457         if (ctask->state == ISCSI_TASK_PENDING) {
1458                 fail_command(conn, ctask, DID_ABORT << 16);
1459                 goto success;
1460         }
1461
1462         /* only have one tmf outstanding at a time */
1463         if (conn->tmf_state != TMF_INITIAL)
1464                 goto failed;
1465         conn->tmf_state = TMF_QUEUED;
1466
1467         hdr = &conn->tmhdr;
1468         iscsi_prep_abort_task_pdu(ctask, hdr);
1469
1470         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
1471                 rc = FAILED;
1472                 goto failed;
1473         }
1474
1475         switch (conn->tmf_state) {
1476         case TMF_SUCCESS:
1477                 spin_unlock_bh(&session->lock);
1478                 iscsi_suspend_tx(conn);
1479                 /*
1480                  * clean up task if aborted. grab the recv lock as a writer
1481                  */
1482                 write_lock_bh(conn->recv_lock);
1483                 spin_lock(&session->lock);
1484                 fail_command(conn, ctask, DID_ABORT << 16);
1485                 conn->tmf_state = TMF_INITIAL;
1486                 spin_unlock(&session->lock);
1487                 write_unlock_bh(conn->recv_lock);
1488                 iscsi_start_tx(conn);
1489                 goto success_unlocked;
1490         case TMF_TIMEDOUT:
1491                 spin_unlock_bh(&session->lock);
1492                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1493                 goto failed_unlocked;
1494         case TMF_NOT_FOUND:
1495                 if (!sc->SCp.ptr) {
1496                         conn->tmf_state = TMF_INITIAL;
1497                         /* ctask completed before tmf abort response */
1498                         debug_scsi("sc completed while abort in progress\n");
1499                         goto success;
1500                 }
1501                 /* fall through */
1502         default:
1503                 conn->tmf_state = TMF_INITIAL;
1504                 goto failed;
1505         }
1506
1507 success:
1508         spin_unlock_bh(&session->lock);
1509 success_unlocked:
1510         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1511         mutex_unlock(&session->eh_mutex);
1512         return SUCCESS;
1513
1514 failed:
1515         spin_unlock_bh(&session->lock);
1516 failed_unlocked:
1517         debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
1518                     ctask ? ctask->itt : 0);
1519         mutex_unlock(&session->eh_mutex);
1520         return FAILED;
1521 }
1522 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1523
1524 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
1525 {
1526         memset(hdr, 0, sizeof(*hdr));
1527         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1528         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
1529         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1530         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
1531         hdr->rtt = RESERVED_ITT;
1532 }
1533
1534 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
1535 {
1536         struct Scsi_Host *host = sc->device->host;
1537         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1538         struct iscsi_conn *conn;
1539         struct iscsi_tm *hdr;
1540         int rc = FAILED;
1541
1542         debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
1543
1544         mutex_lock(&session->eh_mutex);
1545         spin_lock_bh(&session->lock);
1546         /*
1547          * Just check if we are not logged in. We cannot check for
1548          * the phase because the reset could come from a ioctl.
1549          */
1550         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
1551                 goto unlock;
1552         conn = session->leadconn;
1553
1554         /* only have one tmf outstanding at a time */
1555         if (conn->tmf_state != TMF_INITIAL)
1556                 goto unlock;
1557         conn->tmf_state = TMF_QUEUED;
1558
1559         hdr = &conn->tmhdr;
1560         iscsi_prep_lun_reset_pdu(sc, hdr);
1561
1562         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
1563                                     session->lu_reset_timeout)) {
1564                 rc = FAILED;
1565                 goto unlock;
1566         }
1567
1568         switch (conn->tmf_state) {
1569         case TMF_SUCCESS:
1570                 break;
1571         case TMF_TIMEDOUT:
1572                 spin_unlock_bh(&session->lock);
1573                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1574                 goto done;
1575         default:
1576                 conn->tmf_state = TMF_INITIAL;
1577                 goto unlock;
1578         }
1579
1580         rc = SUCCESS;
1581         spin_unlock_bh(&session->lock);
1582
1583         iscsi_suspend_tx(conn);
1584         /* need to grab the recv lock then session lock */
1585         write_lock_bh(conn->recv_lock);
1586         spin_lock(&session->lock);
1587         fail_all_commands(conn, sc->device->lun, DID_ERROR);
1588         conn->tmf_state = TMF_INITIAL;
1589         spin_unlock(&session->lock);
1590         write_unlock_bh(conn->recv_lock);
1591
1592         iscsi_start_tx(conn);
1593         goto done;
1594
1595 unlock:
1596         spin_unlock_bh(&session->lock);
1597 done:
1598         debug_scsi("iscsi_eh_device_reset %s\n",
1599                   rc == SUCCESS ? "SUCCESS" : "FAILED");
1600         mutex_unlock(&session->eh_mutex);
1601         return rc;
1602 }
1603 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
1604
1605 /*
1606  * Pre-allocate a pool of @max items of @item_size. By default, the pool
1607  * should be accessed via kfifo_{get,put} on q->queue.
1608  * Optionally, the caller can obtain the array of object pointers
1609  * by passing in a non-NULL @items pointer
1610  */
1611 int
1612 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
1613 {
1614         int i, num_arrays = 1;
1615
1616         memset(q, 0, sizeof(*q));
1617
1618         q->max = max;
1619
1620         /* If the user passed an items pointer, he wants a copy of
1621          * the array. */
1622         if (items)
1623                 num_arrays++;
1624         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
1625         if (q->pool == NULL)
1626                 goto enomem;
1627
1628         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1629                               GFP_KERNEL, NULL);
1630         if (q->queue == ERR_PTR(-ENOMEM))
1631                 goto enomem;
1632
1633         for (i = 0; i < max; i++) {
1634                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
1635                 if (q->pool[i] == NULL) {
1636                         q->max = i;
1637                         goto enomem;
1638                 }
1639                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1640         }
1641
1642         if (items) {
1643                 *items = q->pool + max;
1644                 memcpy(*items, q->pool, max * sizeof(void *));
1645         }
1646
1647         return 0;
1648
1649 enomem:
1650         iscsi_pool_free(q);
1651         return -ENOMEM;
1652 }
1653 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1654
1655 void iscsi_pool_free(struct iscsi_pool *q)
1656 {
1657         int i;
1658
1659         for (i = 0; i < q->max; i++)
1660                 kfree(q->pool[i]);
1661         if (q->pool)
1662                 kfree(q->pool);
1663 }
1664 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1665
1666 /*
1667  * iSCSI Session's hostdata organization:
1668  *
1669  *    *------------------* <== hostdata_session(host->hostdata)
1670  *    | ptr to class sess|
1671  *    |------------------| <== iscsi_hostdata(host->hostdata)
1672  *    | iscsi_session    |
1673  *    *------------------*
1674  */
1675
1676 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1677                                  _sz % sizeof(unsigned long))
1678
1679 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1680
1681 /**
1682  * iscsi_session_setup - create iscsi cls session and host and session
1683  * @scsit: scsi transport template
1684  * @iscsit: iscsi transport template
1685  * @cmds_max: scsi host can queue
1686  * @qdepth: scsi host cmds per lun
1687  * @cmd_task_size: LLD ctask private data size
1688  * @mgmt_task_size: LLD mtask private data size
1689  * @initial_cmdsn: initial CmdSN
1690  * @hostno: host no allocated
1691  *
1692  * This can be used by software iscsi_transports that allocate
1693  * a session per scsi host.
1694  **/
1695 struct iscsi_cls_session *
1696 iscsi_session_setup(struct iscsi_transport *iscsit,
1697                     struct scsi_transport_template *scsit,
1698                     uint16_t cmds_max, uint16_t qdepth,
1699                     int cmd_task_size, int mgmt_task_size,
1700                     uint32_t initial_cmdsn, uint32_t *hostno)
1701 {
1702         struct Scsi_Host *shost;
1703         struct iscsi_session *session;
1704         struct iscsi_cls_session *cls_session;
1705         int cmd_i;
1706
1707         if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
1708                 if (qdepth != 0)
1709                         printk(KERN_ERR "iscsi: invalid queue depth of %d. "
1710                               "Queue depth must be between 1 and %d.\n",
1711                               qdepth, ISCSI_MAX_CMD_PER_LUN);
1712                 qdepth = ISCSI_DEF_CMD_PER_LUN;
1713         }
1714
1715         if (!is_power_of_2(cmds_max) ||
1716             cmds_max >= ISCSI_MGMT_ITT_OFFSET) {
1717                 if (cmds_max != 0)
1718                         printk(KERN_ERR "iscsi: invalid can_queue of %d. "
1719                                "can_queue must be a power of 2 and between "
1720                                "2 and %d - setting to %d.\n", cmds_max,
1721                                ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
1722                 cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
1723         }
1724
1725         shost = scsi_host_alloc(iscsit->host_template,
1726                                 hostdata_privsize(sizeof(*session)));
1727         if (!shost)
1728                 return NULL;
1729
1730         /* the iscsi layer takes one task for reserve */
1731         shost->can_queue = cmds_max - 1;
1732         shost->cmd_per_lun = qdepth;
1733         shost->max_id = 1;
1734         shost->max_channel = 0;
1735         shost->max_lun = iscsit->max_lun;
1736         shost->max_cmd_len = iscsit->max_cmd_len;
1737         shost->transportt = scsit;
1738         shost->transportt->create_work_queue = 1;
1739         shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
1740         *hostno = shost->host_no;
1741
1742         session = iscsi_hostdata(shost->hostdata);
1743         memset(session, 0, sizeof(struct iscsi_session));
1744         session->host = shost;
1745         session->state = ISCSI_STATE_FREE;
1746         session->fast_abort = 1;
1747         session->lu_reset_timeout = 15;
1748         session->abort_timeout = 10;
1749         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1750         session->cmds_max = cmds_max;
1751         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
1752         session->exp_cmdsn = initial_cmdsn + 1;
1753         session->max_cmdsn = initial_cmdsn + 1;
1754         session->max_r2t = 1;
1755         session->tt = iscsit;
1756         mutex_init(&session->eh_mutex);
1757
1758         /* initialize SCSI PDU commands pool */
1759         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1760                             (void***)&session->cmds,
1761                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1762                 goto cmdpool_alloc_fail;
1763
1764         /* pre-format cmds pool with ITT */
1765         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1766                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1767
1768                 if (cmd_task_size)
1769                         ctask->dd_data = &ctask[1];
1770                 ctask->itt = cmd_i;
1771                 INIT_LIST_HEAD(&ctask->running);
1772         }
1773
1774         spin_lock_init(&session->lock);
1775
1776         /* initialize immediate command pool */
1777         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1778                            (void***)&session->mgmt_cmds,
1779                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1780                 goto mgmtpool_alloc_fail;
1781
1782
1783         /* pre-format immediate cmds pool with ITT */
1784         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1785                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1786
1787                 if (mgmt_task_size)
1788                         mtask->dd_data = &mtask[1];
1789                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1790                 INIT_LIST_HEAD(&mtask->running);
1791         }
1792
1793         if (scsi_add_host(shost, NULL))
1794                 goto add_host_fail;
1795
1796         if (!try_module_get(iscsit->owner))
1797                 goto cls_session_fail;
1798
1799         cls_session = iscsi_create_session(shost, iscsit, 0);
1800         if (!cls_session)
1801                 goto module_put;
1802         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1803
1804         return cls_session;
1805
1806 module_put:
1807         module_put(iscsit->owner);
1808 cls_session_fail:
1809         scsi_remove_host(shost);
1810 add_host_fail:
1811         iscsi_pool_free(&session->mgmtpool);
1812 mgmtpool_alloc_fail:
1813         iscsi_pool_free(&session->cmdpool);
1814 cmdpool_alloc_fail:
1815         scsi_host_put(shost);
1816         return NULL;
1817 }
1818 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1819
1820 /**
1821  * iscsi_session_teardown - destroy session, host, and cls_session
1822  * shost: scsi host
1823  *
1824  * This can be used by software iscsi_transports that allocate
1825  * a session per scsi host.
1826  **/
1827 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1828 {
1829         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1830         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1831         struct module *owner = cls_session->transport->owner;
1832
1833         iscsi_remove_session(cls_session);
1834         scsi_remove_host(shost);
1835
1836         iscsi_pool_free(&session->mgmtpool);
1837         iscsi_pool_free(&session->cmdpool);
1838
1839         kfree(session->password);
1840         kfree(session->password_in);
1841         kfree(session->username);
1842         kfree(session->username_in);
1843         kfree(session->targetname);
1844         kfree(session->netdev);
1845         kfree(session->hwaddress);
1846         kfree(session->initiatorname);
1847
1848         iscsi_free_session(cls_session);
1849         scsi_host_put(shost);
1850         module_put(owner);
1851 }
1852 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1853
1854 /**
1855  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1856  * @cls_session: iscsi_cls_session
1857  * @conn_idx: cid
1858  **/
1859 struct iscsi_cls_conn *
1860 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1861 {
1862         struct iscsi_session *session = class_to_transport_session(cls_session);
1863         struct iscsi_conn *conn;
1864         struct iscsi_cls_conn *cls_conn;
1865         char *data;
1866
1867         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1868         if (!cls_conn)
1869                 return NULL;
1870         conn = cls_conn->dd_data;
1871         memset(conn, 0, sizeof(*conn));
1872
1873         conn->session = session;
1874         conn->cls_conn = cls_conn;
1875         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1876         conn->id = conn_idx;
1877         conn->exp_statsn = 0;
1878         conn->tmf_state = TMF_INITIAL;
1879
1880         init_timer(&conn->transport_timer);
1881         conn->transport_timer.data = (unsigned long)conn;
1882         conn->transport_timer.function = iscsi_check_transport_timeouts;
1883
1884         INIT_LIST_HEAD(&conn->run_list);
1885         INIT_LIST_HEAD(&conn->mgmt_run_list);
1886         INIT_LIST_HEAD(&conn->mgmtqueue);
1887         INIT_LIST_HEAD(&conn->xmitqueue);
1888         INIT_LIST_HEAD(&conn->requeue);
1889         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
1890
1891         /* allocate login_mtask used for the login/text sequences */
1892         spin_lock_bh(&session->lock);
1893         if (!__kfifo_get(session->mgmtpool.queue,
1894                          (void*)&conn->login_mtask,
1895                          sizeof(void*))) {
1896                 spin_unlock_bh(&session->lock);
1897                 goto login_mtask_alloc_fail;
1898         }
1899         spin_unlock_bh(&session->lock);
1900
1901         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
1902         if (!data)
1903                 goto login_mtask_data_alloc_fail;
1904         conn->login_mtask->data = conn->data = data;
1905
1906         init_timer(&conn->tmf_timer);
1907         init_waitqueue_head(&conn->ehwait);
1908
1909         return cls_conn;
1910
1911 login_mtask_data_alloc_fail:
1912         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1913                     sizeof(void*));
1914 login_mtask_alloc_fail:
1915         iscsi_destroy_conn(cls_conn);
1916         return NULL;
1917 }
1918 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1919
1920 /**
1921  * iscsi_conn_teardown - teardown iscsi connection
1922  * cls_conn: iscsi class connection
1923  *
1924  * TODO: we may need to make this into a two step process
1925  * like scsi-mls remove + put host
1926  */
1927 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1928 {
1929         struct iscsi_conn *conn = cls_conn->dd_data;
1930         struct iscsi_session *session = conn->session;
1931         unsigned long flags;
1932
1933         del_timer_sync(&conn->transport_timer);
1934
1935         spin_lock_bh(&session->lock);
1936         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1937         if (session->leadconn == conn) {
1938                 /*
1939                  * leading connection? then give up on recovery.
1940                  */
1941                 session->state = ISCSI_STATE_TERMINATE;
1942                 wake_up(&conn->ehwait);
1943         }
1944         spin_unlock_bh(&session->lock);
1945
1946         /*
1947          * Block until all in-progress commands for this connection
1948          * time out or fail.
1949          */
1950         for (;;) {
1951                 spin_lock_irqsave(session->host->host_lock, flags);
1952                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1953                         spin_unlock_irqrestore(session->host->host_lock, flags);
1954                         break;
1955                 }
1956                 spin_unlock_irqrestore(session->host->host_lock, flags);
1957                 msleep_interruptible(500);
1958                 printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
1959                        "host_failed %d\n", session->host->host_busy,
1960                        session->host->host_failed);
1961                 /*
1962                  * force eh_abort() to unblock
1963                  */
1964                 wake_up(&conn->ehwait);
1965         }
1966
1967         /* flush queued up work because we free the connection below */
1968         iscsi_suspend_tx(conn);
1969
1970         spin_lock_bh(&session->lock);
1971         kfree(conn->data);
1972         kfree(conn->persistent_address);
1973         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1974                     sizeof(void*));
1975         if (session->leadconn == conn)
1976                 session->leadconn = NULL;
1977         spin_unlock_bh(&session->lock);
1978
1979         iscsi_destroy_conn(cls_conn);
1980 }
1981 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1982
1983 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1984 {
1985         struct iscsi_conn *conn = cls_conn->dd_data;
1986         struct iscsi_session *session = conn->session;
1987
1988         if (!session) {
1989                 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1990                 return -EPERM;
1991         }
1992
1993         if ((session->imm_data_en || !session->initial_r2t_en) &&
1994              session->first_burst > session->max_burst) {
1995                 printk("iscsi: invalid burst lengths: "
1996                        "first_burst %d max_burst %d\n",
1997                        session->first_burst, session->max_burst);
1998                 return -EINVAL;
1999         }
2000
2001         if (conn->ping_timeout && !conn->recv_timeout) {
2002                 printk(KERN_ERR "iscsi: invalid recv timeout of zero "
2003                       "Using 5 seconds\n.");
2004                 conn->recv_timeout = 5;
2005         }
2006
2007         if (conn->recv_timeout && !conn->ping_timeout) {
2008                 printk(KERN_ERR "iscsi: invalid ping timeout of zero "
2009                       "Using 5 seconds.\n");
2010                 conn->ping_timeout = 5;
2011         }
2012
2013         spin_lock_bh(&session->lock);
2014         conn->c_stage = ISCSI_CONN_STARTED;
2015         session->state = ISCSI_STATE_LOGGED_IN;
2016         session->queued_cmdsn = session->cmdsn;
2017
2018         conn->last_recv = jiffies;
2019         conn->last_ping = jiffies;
2020         if (conn->recv_timeout && conn->ping_timeout)
2021                 mod_timer(&conn->transport_timer,
2022                           jiffies + (conn->recv_timeout * HZ));
2023
2024         switch(conn->stop_stage) {
2025         case STOP_CONN_RECOVER:
2026                 /*
2027                  * unblock eh_abort() if it is blocked. re-try all
2028                  * commands after successful recovery
2029                  */
2030                 conn->stop_stage = 0;
2031                 conn->tmf_state = TMF_INITIAL;
2032                 session->age++;
2033                 break;
2034         case STOP_CONN_TERM:
2035                 conn->stop_stage = 0;
2036                 break;
2037         default:
2038                 break;
2039         }
2040         spin_unlock_bh(&session->lock);
2041
2042         iscsi_unblock_session(session_to_cls(session));
2043         wake_up(&conn->ehwait);
2044         return 0;
2045 }
2046 EXPORT_SYMBOL_GPL(iscsi_conn_start);
2047
2048 static void
2049 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
2050 {
2051         struct iscsi_mgmt_task *mtask, *tmp;
2052
2053         /* handle pending */
2054         list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
2055                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
2056                 iscsi_free_mgmt_task(conn, mtask);
2057         }
2058
2059         /* handle running */
2060         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
2061                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
2062                 iscsi_free_mgmt_task(conn, mtask);
2063         }
2064
2065         conn->mtask = NULL;
2066 }
2067
2068 static void iscsi_start_session_recovery(struct iscsi_session *session,
2069                                          struct iscsi_conn *conn, int flag)
2070 {
2071         int old_stop_stage;
2072
2073         del_timer_sync(&conn->transport_timer);
2074
2075         mutex_lock(&session->eh_mutex);
2076         spin_lock_bh(&session->lock);
2077         if (conn->stop_stage == STOP_CONN_TERM) {
2078                 spin_unlock_bh(&session->lock);
2079                 mutex_unlock(&session->eh_mutex);
2080                 return;
2081         }
2082
2083         /*
2084          * The LLD either freed/unset the lock on us, or userspace called
2085          * stop but did not create a proper connection (connection was never
2086          * bound or it was unbound then stop was called).
2087          */
2088         if (!conn->recv_lock) {
2089                 spin_unlock_bh(&session->lock);
2090                 mutex_unlock(&session->eh_mutex);
2091                 return;
2092         }
2093
2094         /*
2095          * When this is called for the in_login state, we only want to clean
2096          * up the login task and connection. We do not need to block and set
2097          * the recovery state again
2098          */
2099         if (flag == STOP_CONN_TERM)
2100                 session->state = ISCSI_STATE_TERMINATE;
2101         else if (conn->stop_stage != STOP_CONN_RECOVER)
2102                 session->state = ISCSI_STATE_IN_RECOVERY;
2103
2104         old_stop_stage = conn->stop_stage;
2105         conn->stop_stage = flag;
2106         conn->c_stage = ISCSI_CONN_STOPPED;
2107         spin_unlock_bh(&session->lock);
2108
2109         iscsi_suspend_tx(conn);
2110
2111         write_lock_bh(conn->recv_lock);
2112         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2113         write_unlock_bh(conn->recv_lock);
2114
2115         /*
2116          * for connection level recovery we should not calculate
2117          * header digest. conn->hdr_size used for optimization
2118          * in hdr_extract() and will be re-negotiated at
2119          * set_param() time.
2120          */
2121         if (flag == STOP_CONN_RECOVER) {
2122                 conn->hdrdgst_en = 0;
2123                 conn->datadgst_en = 0;
2124                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
2125                     old_stop_stage != STOP_CONN_RECOVER) {
2126                         debug_scsi("blocking session\n");
2127                         iscsi_block_session(session_to_cls(session));
2128                 }
2129         }
2130
2131         /*
2132          * flush queues.
2133          */
2134         spin_lock_bh(&session->lock);
2135         fail_all_commands(conn, -1,
2136                         STOP_CONN_RECOVER ? DID_BUS_BUSY : DID_ERROR);
2137         flush_control_queues(session, conn);
2138         spin_unlock_bh(&session->lock);
2139         mutex_unlock(&session->eh_mutex);
2140 }
2141
2142 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
2143 {
2144         struct iscsi_conn *conn = cls_conn->dd_data;
2145         struct iscsi_session *session = conn->session;
2146
2147         switch (flag) {
2148         case STOP_CONN_RECOVER:
2149         case STOP_CONN_TERM:
2150                 iscsi_start_session_recovery(session, conn, flag);
2151                 break;
2152         default:
2153                 printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
2154         }
2155 }
2156 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
2157
2158 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
2159                     struct iscsi_cls_conn *cls_conn, int is_leading)
2160 {
2161         struct iscsi_session *session = class_to_transport_session(cls_session);
2162         struct iscsi_conn *conn = cls_conn->dd_data;
2163
2164         spin_lock_bh(&session->lock);
2165         if (is_leading)
2166                 session->leadconn = conn;
2167         spin_unlock_bh(&session->lock);
2168
2169         /*
2170          * Unblock xmitworker(), Login Phase will pass through.
2171          */
2172         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2173         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
2174         return 0;
2175 }
2176 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
2177
2178
2179 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
2180                     enum iscsi_param param, char *buf, int buflen)
2181 {
2182         struct iscsi_conn *conn = cls_conn->dd_data;
2183         struct iscsi_session *session = conn->session;
2184         uint32_t value;
2185
2186         switch(param) {
2187         case ISCSI_PARAM_FAST_ABORT:
2188                 sscanf(buf, "%d", &session->fast_abort);
2189                 break;
2190         case ISCSI_PARAM_ABORT_TMO:
2191                 sscanf(buf, "%d", &session->abort_timeout);
2192                 break;
2193         case ISCSI_PARAM_LU_RESET_TMO:
2194                 sscanf(buf, "%d", &session->lu_reset_timeout);
2195                 break;
2196         case ISCSI_PARAM_PING_TMO:
2197                 sscanf(buf, "%d", &conn->ping_timeout);
2198                 break;
2199         case ISCSI_PARAM_RECV_TMO:
2200                 sscanf(buf, "%d", &conn->recv_timeout);
2201                 break;
2202         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2203                 sscanf(buf, "%d", &conn->max_recv_dlength);
2204                 break;
2205         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2206                 sscanf(buf, "%d", &conn->max_xmit_dlength);
2207                 break;
2208         case ISCSI_PARAM_HDRDGST_EN:
2209                 sscanf(buf, "%d", &conn->hdrdgst_en);
2210                 break;
2211         case ISCSI_PARAM_DATADGST_EN:
2212                 sscanf(buf, "%d", &conn->datadgst_en);
2213                 break;
2214         case ISCSI_PARAM_INITIAL_R2T_EN:
2215                 sscanf(buf, "%d", &session->initial_r2t_en);
2216                 break;
2217         case ISCSI_PARAM_MAX_R2T:
2218                 sscanf(buf, "%d", &session->max_r2t);
2219                 break;
2220         case ISCSI_PARAM_IMM_DATA_EN:
2221                 sscanf(buf, "%d", &session->imm_data_en);
2222                 break;
2223         case ISCSI_PARAM_FIRST_BURST:
2224                 sscanf(buf, "%d", &session->first_burst);
2225                 break;
2226         case ISCSI_PARAM_MAX_BURST:
2227                 sscanf(buf, "%d", &session->max_burst);
2228                 break;
2229         case ISCSI_PARAM_PDU_INORDER_EN:
2230                 sscanf(buf, "%d", &session->pdu_inorder_en);
2231                 break;
2232         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2233                 sscanf(buf, "%d", &session->dataseq_inorder_en);
2234                 break;
2235         case ISCSI_PARAM_ERL:
2236                 sscanf(buf, "%d", &session->erl);
2237                 break;
2238         case ISCSI_PARAM_IFMARKER_EN:
2239                 sscanf(buf, "%d", &value);
2240                 BUG_ON(value);
2241                 break;
2242         case ISCSI_PARAM_OFMARKER_EN:
2243                 sscanf(buf, "%d", &value);
2244                 BUG_ON(value);
2245                 break;
2246         case ISCSI_PARAM_EXP_STATSN:
2247                 sscanf(buf, "%u", &conn->exp_statsn);
2248                 break;
2249         case ISCSI_PARAM_USERNAME:
2250                 kfree(session->username);
2251                 session->username = kstrdup(buf, GFP_KERNEL);
2252                 if (!session->username)
2253                         return -ENOMEM;
2254                 break;
2255         case ISCSI_PARAM_USERNAME_IN:
2256                 kfree(session->username_in);
2257                 session->username_in = kstrdup(buf, GFP_KERNEL);
2258                 if (!session->username_in)
2259                         return -ENOMEM;
2260                 break;
2261         case ISCSI_PARAM_PASSWORD:
2262                 kfree(session->password);
2263                 session->password = kstrdup(buf, GFP_KERNEL);
2264                 if (!session->password)
2265                         return -ENOMEM;
2266                 break;
2267         case ISCSI_PARAM_PASSWORD_IN:
2268                 kfree(session->password_in);
2269                 session->password_in = kstrdup(buf, GFP_KERNEL);
2270                 if (!session->password_in)
2271                         return -ENOMEM;
2272                 break;
2273         case ISCSI_PARAM_TARGET_NAME:
2274                 /* this should not change between logins */
2275                 if (session->targetname)
2276                         break;
2277
2278                 session->targetname = kstrdup(buf, GFP_KERNEL);
2279                 if (!session->targetname)
2280                         return -ENOMEM;
2281                 break;
2282         case ISCSI_PARAM_TPGT:
2283                 sscanf(buf, "%d", &session->tpgt);
2284                 break;
2285         case ISCSI_PARAM_PERSISTENT_PORT:
2286                 sscanf(buf, "%d", &conn->persistent_port);
2287                 break;
2288         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2289                 /*
2290                  * this is the address returned in discovery so it should
2291                  * not change between logins.
2292                  */
2293                 if (conn->persistent_address)
2294                         break;
2295
2296                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
2297                 if (!conn->persistent_address)
2298                         return -ENOMEM;
2299                 break;
2300         default:
2301                 return -ENOSYS;
2302         }
2303
2304         return 0;
2305 }
2306 EXPORT_SYMBOL_GPL(iscsi_set_param);
2307
2308 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
2309                             enum iscsi_param param, char *buf)
2310 {
2311         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
2312         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2313         int len;
2314
2315         switch(param) {
2316         case ISCSI_PARAM_FAST_ABORT:
2317                 len = sprintf(buf, "%d\n", session->fast_abort);
2318                 break;
2319         case ISCSI_PARAM_ABORT_TMO:
2320                 len = sprintf(buf, "%d\n", session->abort_timeout);
2321                 break;
2322         case ISCSI_PARAM_LU_RESET_TMO:
2323                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
2324                 break;
2325         case ISCSI_PARAM_INITIAL_R2T_EN:
2326                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
2327                 break;
2328         case ISCSI_PARAM_MAX_R2T:
2329                 len = sprintf(buf, "%hu\n", session->max_r2t);
2330                 break;
2331         case ISCSI_PARAM_IMM_DATA_EN:
2332                 len = sprintf(buf, "%d\n", session->imm_data_en);
2333                 break;
2334         case ISCSI_PARAM_FIRST_BURST:
2335                 len = sprintf(buf, "%u\n", session->first_burst);
2336                 break;
2337         case ISCSI_PARAM_MAX_BURST:
2338                 len = sprintf(buf, "%u\n", session->max_burst);
2339                 break;
2340         case ISCSI_PARAM_PDU_INORDER_EN:
2341                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
2342                 break;
2343         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2344                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
2345                 break;
2346         case ISCSI_PARAM_ERL:
2347                 len = sprintf(buf, "%d\n", session->erl);
2348                 break;
2349         case ISCSI_PARAM_TARGET_NAME:
2350                 len = sprintf(buf, "%s\n", session->targetname);
2351                 break;
2352         case ISCSI_PARAM_TPGT:
2353                 len = sprintf(buf, "%d\n", session->tpgt);
2354                 break;
2355         case ISCSI_PARAM_USERNAME:
2356                 len = sprintf(buf, "%s\n", session->username);
2357                 break;
2358         case ISCSI_PARAM_USERNAME_IN:
2359                 len = sprintf(buf, "%s\n", session->username_in);
2360                 break;
2361         case ISCSI_PARAM_PASSWORD:
2362                 len = sprintf(buf, "%s\n", session->password);
2363                 break;
2364         case ISCSI_PARAM_PASSWORD_IN:
2365                 len = sprintf(buf, "%s\n", session->password_in);
2366                 break;
2367         default:
2368                 return -ENOSYS;
2369         }
2370
2371         return len;
2372 }
2373 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
2374
2375 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
2376                          enum iscsi_param param, char *buf)
2377 {
2378         struct iscsi_conn *conn = cls_conn->dd_data;
2379         int len;
2380
2381         switch(param) {
2382         case ISCSI_PARAM_PING_TMO:
2383                 len = sprintf(buf, "%u\n", conn->ping_timeout);
2384                 break;
2385         case ISCSI_PARAM_RECV_TMO:
2386                 len = sprintf(buf, "%u\n", conn->recv_timeout);
2387                 break;
2388         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2389                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
2390                 break;
2391         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2392                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
2393                 break;
2394         case ISCSI_PARAM_HDRDGST_EN:
2395                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
2396                 break;
2397         case ISCSI_PARAM_DATADGST_EN:
2398                 len = sprintf(buf, "%d\n", conn->datadgst_en);
2399                 break;
2400         case ISCSI_PARAM_IFMARKER_EN:
2401                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
2402                 break;
2403         case ISCSI_PARAM_OFMARKER_EN:
2404                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
2405                 break;
2406         case ISCSI_PARAM_EXP_STATSN:
2407                 len = sprintf(buf, "%u\n", conn->exp_statsn);
2408                 break;
2409         case ISCSI_PARAM_PERSISTENT_PORT:
2410                 len = sprintf(buf, "%d\n", conn->persistent_port);
2411                 break;
2412         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2413                 len = sprintf(buf, "%s\n", conn->persistent_address);
2414                 break;
2415         default:
2416                 return -ENOSYS;
2417         }
2418
2419         return len;
2420 }
2421 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
2422
2423 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2424                          char *buf)
2425 {
2426         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2427         int len;
2428
2429         switch (param) {
2430         case ISCSI_HOST_PARAM_NETDEV_NAME:
2431                 if (!session->netdev)
2432                         len = sprintf(buf, "%s\n", "default");
2433                 else
2434                         len = sprintf(buf, "%s\n", session->netdev);
2435                 break;
2436         case ISCSI_HOST_PARAM_HWADDRESS:
2437                 if (!session->hwaddress)
2438                         len = sprintf(buf, "%s\n", "default");
2439                 else
2440                         len = sprintf(buf, "%s\n", session->hwaddress);
2441                 break;
2442         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2443                 if (!session->initiatorname)
2444                         len = sprintf(buf, "%s\n", "unknown");
2445                 else
2446                         len = sprintf(buf, "%s\n", session->initiatorname);
2447                 break;
2448
2449         default:
2450                 return -ENOSYS;
2451         }
2452
2453         return len;
2454 }
2455 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2456
2457 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2458                          char *buf, int buflen)
2459 {
2460         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2461
2462         switch (param) {
2463         case ISCSI_HOST_PARAM_NETDEV_NAME:
2464                 if (!session->netdev)
2465                         session->netdev = kstrdup(buf, GFP_KERNEL);
2466                 break;
2467         case ISCSI_HOST_PARAM_HWADDRESS:
2468                 if (!session->hwaddress)
2469                         session->hwaddress = kstrdup(buf, GFP_KERNEL);
2470                 break;
2471         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2472                 if (!session->initiatorname)
2473                         session->initiatorname = kstrdup(buf, GFP_KERNEL);
2474                 break;
2475         default:
2476                 return -ENOSYS;
2477         }
2478
2479         return 0;
2480 }
2481 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2482
2483 MODULE_AUTHOR("Mike Christie");
2484 MODULE_DESCRIPTION("iSCSI library functions");
2485 MODULE_LICENSE("GPL");