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/mutex.h>
  26 #include <linux/kfifo.h>
  27 #include <linux/delay.h>
  28 #include <net/tcp.h>
  29 #include <scsi/scsi_cmnd.h>
  30 #include <scsi/scsi_device.h>
  31 #include <scsi/scsi_eh.h>
  32 #include <scsi/scsi_tcq.h>
  33 #include <scsi/scsi_host.h>
  34 #include <scsi/scsi.h>
  35 #include <scsi/iscsi_proto.h>
  36 #include <scsi/scsi_transport.h>
  37 #include <scsi/scsi_transport_iscsi.h>
  38 #include <scsi/libiscsi.h>
  39
  40 struct iscsi_session *
  41 class_to_transport_session(struct iscsi_cls_session *cls_session)
  42 {
  43         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
  44         return iscsi_hostdata(shost->hostdata);
  45 }
  46 EXPORT_SYMBOL_GPL(class_to_transport_session);
  47
  48 #define INVALID_SN_DELTA        0xffff
  49
  50 int
  51 iscsi_check_assign_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
  52 {
  53         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
  54         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
  55
  56         if (max_cmdsn < exp_cmdsn -1 &&
  57             max_cmdsn > exp_cmdsn - INVALID_SN_DELTA)
  58                 return ISCSI_ERR_MAX_CMDSN;
  59         if (max_cmdsn > session->max_cmdsn ||
  60             max_cmdsn < session->max_cmdsn - INVALID_SN_DELTA)
  61                 session->max_cmdsn = max_cmdsn;
  62         if (exp_cmdsn > session->exp_cmdsn ||
  63             exp_cmdsn < session->exp_cmdsn - INVALID_SN_DELTA)
  64                 session->exp_cmdsn = exp_cmdsn;
  65
  66         return 0;
  67 }
  68 EXPORT_SYMBOL_GPL(iscsi_check_assign_cmdsn);
  69
  70 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
  71                                    struct iscsi_data *hdr,
  72                                    int transport_data_cnt)
  73 {
  74         struct iscsi_conn *conn = ctask->conn;
  75
  76         memset(hdr, 0, sizeof(struct iscsi_data));
  77         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
  78         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
  79         ctask->unsol_datasn++;
  80         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
  81         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
  82
  83         hdr->itt = ctask->hdr->itt;
  84         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
  85
  86         hdr->offset = cpu_to_be32(ctask->total_length -
  87                                   transport_data_cnt -
  88                                   ctask->unsol_count);
  89
  90         if (ctask->unsol_count > conn->max_xmit_dlength) {
  91                 hton24(hdr->dlength, conn->max_xmit_dlength);
  92                 ctask->data_count = conn->max_xmit_dlength;
  93                 hdr->flags = 0;
  94         } else {
  95                 hton24(hdr->dlength, ctask->unsol_count);
  96                 ctask->data_count = ctask->unsol_count;
  97                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
  98         }
  99 }
 100 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
 101
 102 /**
 103  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
 104  * @ctask: iscsi cmd task
 105  *
 106  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
 107  * fields like dlength or final based on how much data it sends
 108  */
 109 static void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
 110 {
 111         struct iscsi_conn *conn = ctask->conn;
 112         struct iscsi_session *session = conn->session;
 113         struct iscsi_cmd *hdr = ctask->hdr;
 114         struct scsi_cmnd *sc = ctask->sc;
 115
 116         hdr->opcode = ISCSI_OP_SCSI_CMD;
 117         hdr->flags = ISCSI_ATTR_SIMPLE;
 118         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
 119         hdr->itt = ctask->itt | (conn->id << ISCSI_CID_SHIFT) |
 120                          (session->age << ISCSI_AGE_SHIFT);
 121         hdr->data_length = cpu_to_be32(sc->request_bufflen);
 122         hdr->cmdsn = cpu_to_be32(session->cmdsn);
 123         session->cmdsn++;
 124         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 125         memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
 126         memset(&hdr->cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len);
 127
 128         if (sc->sc_data_direction == DMA_TO_DEVICE) {
 129                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 130                 /*
 131                  * Write counters:
 132                  *
 133                  *      imm_count       bytes to be sent right after
 134                  *                      SCSI PDU Header
 135                  *
 136                  *      unsol_count     bytes(as Data-Out) to be sent
 137                  *                      without R2T ack right after
 138                  *                      immediate data
 139                  *
 140                  *      r2t_data_count  bytes to be sent via R2T ack's
 141                  *
 142                  *      pad_count       bytes to be sent as zero-padding
 143                  */
 144                 ctask->imm_count = 0;
 145                 ctask->unsol_count = 0;
 146                 ctask->unsol_datasn = 0;
 147
 148                 if (session->imm_data_en) {
 149                         if (ctask->total_length >= session->first_burst)
 150                                 ctask->imm_count = min(session->first_burst,
 151                                                         conn->max_xmit_dlength);
 152                         else
 153                                 ctask->imm_count = min(ctask->total_length,
 154                                                         conn->max_xmit_dlength);
 155                         hton24(ctask->hdr->dlength, ctask->imm_count);
 156                 } else
 157                         zero_data(ctask->hdr->dlength);
 158
 159                 if (!session->initial_r2t_en)
 160                         ctask->unsol_count = min(session->first_burst,
 161                                 ctask->total_length) - ctask->imm_count;
 162                 if (!ctask->unsol_count)
 163                         /* No unsolicit Data-Out's */
 164                         ctask->hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 165         } else {
 166                 ctask->datasn = 0;
 167                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 168                 zero_data(hdr->dlength);
 169
 170                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
 171                         hdr->flags |= ISCSI_FLAG_CMD_READ;
 172         }
 173
 174         conn->scsicmd_pdus_cnt++;
 175 }
 176 EXPORT_SYMBOL_GPL(iscsi_prep_scsi_cmd_pdu);
 177
 178 /**
 179  * iscsi_complete_command - return command back to scsi-ml
 180  * @session: iscsi session
 181  * @ctask: iscsi cmd task
 182  *
 183  * Must be called with session lock.
 184  * This function returns the scsi command to scsi-ml and returns
 185  * the cmd task to the pool of available cmd tasks.
 186  */
 187 static void iscsi_complete_command(struct iscsi_session *session,
 188                                    struct iscsi_cmd_task *ctask)
 189 {
 190         struct scsi_cmnd *sc = ctask->sc;
 191
 192         ctask->state = ISCSI_TASK_COMPLETED;
 193         ctask->sc = NULL;
 194         list_del_init(&ctask->running);
 195         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
 196         sc->scsi_done(sc);
 197 }
 198
 199 /**
 200  * iscsi_cmd_rsp - SCSI Command Response processing
 201  * @conn: iscsi connection
 202  * @hdr: iscsi header
 203  * @ctask: scsi command task
 204  * @data: cmd data buffer
 205  * @datalen: len of buffer
 206  *
 207  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 208  * then completes the command and task.
 209  **/
 210 static int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 211                               struct iscsi_cmd_task *ctask, char *data,
 212                               int datalen)
 213 {
 214         int rc;
 215         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
 216         struct iscsi_session *session = conn->session;
 217         struct scsi_cmnd *sc = ctask->sc;
 218
 219         rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
 220         if (rc) {
 221                 sc->result = DID_ERROR << 16;
 222                 goto out;
 223         }
 224
 225         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 226
 227         sc->result = (DID_OK << 16) | rhdr->cmd_status;
 228
 229         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 230                 sc->result = DID_ERROR << 16;
 231                 goto out;
 232         }
 233
 234         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 235                 int senselen;
 236
 237                 if (datalen < 2) {
 238 invalid_datalen:
 239                         printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
 240                                "invalid data buffer size of %d\n", datalen);
 241                         sc->result = DID_BAD_TARGET << 16;
 242                         goto out;
 243                 }
 244
 245                 senselen = (data[0] << 8) | data[1];
 246                 if (datalen < senselen)
 247                         goto invalid_datalen;
 248
 249                 memcpy(sc->sense_buffer, data + 2,
 250                        min(senselen, SCSI_SENSE_BUFFERSIZE));
 251                 debug_scsi("copied %d bytes of sense\n",
 252                            min(senselen, SCSI_SENSE_BUFFERSIZE));
 253         }
 254
 255         if (sc->sc_data_direction == DMA_TO_DEVICE)
 256                 goto out;
 257
 258         if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
 259                 int res_count = be32_to_cpu(rhdr->residual_count);
 260
 261                 if (res_count > 0 && res_count <= sc->request_bufflen)
 262                         sc->resid = res_count;
 263                 else
 264                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 265         } else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
 266                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 267         else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW)
 268                 sc->resid = be32_to_cpu(rhdr->residual_count);
 269
 270 out:
 271         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
 272                    (long)sc, sc->result, ctask->itt);
 273         conn->scsirsp_pdus_cnt++;
 274
 275         iscsi_complete_command(conn->session, ctask);
 276         return rc;
 277 }
 278
 279 /**
 280  * __iscsi_complete_pdu - complete pdu
 281  * @conn: iscsi conn
 282  * @hdr: iscsi header
 283  * @data: data buffer
 284  * @datalen: len of data buffer
 285  *
 286  * Completes pdu processing by freeing any resources allocated at
 287  * queuecommand or send generic. session lock must be held and verify
 288  * itt must have been called.
 289  */
 290 int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 291                          char *data, int datalen)
 292 {
 293         struct iscsi_session *session = conn->session;
 294         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
 295         struct iscsi_cmd_task *ctask;
 296         struct iscsi_mgmt_task *mtask;
 297         uint32_t itt;
 298
 299         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG))
 300                 itt = hdr->itt & ISCSI_ITT_MASK;
 301         else
 302                 itt = hdr->itt;
 303
 304         if (itt < session->cmds_max) {
 305                 ctask = session->cmds[itt];
 306
 307                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 308                            opcode, conn->id, ctask->itt, datalen);
 309
 310                 switch(opcode) {
 311                 case ISCSI_OP_SCSI_CMD_RSP:
 312                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 313                         rc = iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
 314                                                 datalen);
 315                         break;
 316                 case ISCSI_OP_SCSI_DATA_IN:
 317                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 318                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
 319                                 conn->scsirsp_pdus_cnt++;
 320                                 iscsi_complete_command(session, ctask);
 321                         }
 322                         break;
 323                 case ISCSI_OP_R2T:
 324                         /* LLD handles this for now */
 325                         break;
 326                 default:
 327                         rc = ISCSI_ERR_BAD_OPCODE;
 328                         break;
 329                 }
 330         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
 331                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
 332                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
 333
 334                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 335                            opcode, conn->id, mtask->itt, datalen);
 336
 337                 rc = iscsi_check_assign_cmdsn(session,
 338                                               (struct iscsi_nopin*)hdr);
 339                 if (rc)
 340                         goto done;
 341
 342                 switch(opcode) {
 343                 case ISCSI_OP_LOGOUT_RSP:
 344                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 345                         /* fall through */
 346                 case ISCSI_OP_LOGIN_RSP:
 347                 case ISCSI_OP_TEXT_RSP:
 348                         /*
 349                          * login related PDU's exp_statsn is handled in
 350                          * userspace
 351                          */
 352                         rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen);
 353                         list_del(&mtask->running);
 354                         if (conn->login_mtask != mtask)
 355                                 __kfifo_put(session->mgmtpool.queue,
 356                                             (void*)&mtask, sizeof(void*));
 357                         break;
 358                 case ISCSI_OP_SCSI_TMFUNC_RSP:
 359                         if (datalen) {
 360                                 rc = ISCSI_ERR_PROTO;
 361                                 break;
 362                         }
 363
 364                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 365                         conn->tmfrsp_pdus_cnt++;
 366                         if (conn->tmabort_state == TMABORT_INITIAL) {
 367                                 conn->tmabort_state =
 368                                         ((struct iscsi_tm_rsp *)hdr)->
 369                                         response == ISCSI_TMF_RSP_COMPLETE ?
 370                                                 TMABORT_SUCCESS:TMABORT_FAILED;
 371                                 /* unblock eh_abort() */
 372                                 wake_up(&conn->ehwait);
 373                         }
 374                         break;
 375                 case ISCSI_OP_NOOP_IN:
 376                         if (hdr->ttt != ISCSI_RESERVED_TAG) {
 377                                 rc = ISCSI_ERR_PROTO;
 378                                 break;
 379                         }
 380                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 381
 382                         rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen);
 383                         list_del(&mtask->running);
 384                         if (conn->login_mtask != mtask)
 385                                 __kfifo_put(session->mgmtpool.queue,
 386                                             (void*)&mtask, sizeof(void*));
 387                         break;
 388                 default:
 389                         rc = ISCSI_ERR_BAD_OPCODE;
 390                         break;
 391                 }
 392         } else if (itt == ISCSI_RESERVED_TAG) {
 393                 switch(opcode) {
 394                 case ISCSI_OP_NOOP_IN:
 395                         if (!datalen) {
 396                                 rc = iscsi_check_assign_cmdsn(session,
 397                                                  (struct iscsi_nopin*)hdr);
 398                                 if (!rc && hdr->ttt != ISCSI_RESERVED_TAG)
 399                                         rc = iscsi_recv_pdu(conn->cls_conn,
 400                                                             hdr, NULL, 0);
 401                         } else
 402                                 rc = ISCSI_ERR_PROTO;
 403                         break;
 404                 case ISCSI_OP_REJECT:
 405                         /* we need sth like iscsi_reject_rsp()*/
 406                 case ISCSI_OP_ASYNC_EVENT:
 407                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 408                         /* we need sth like iscsi_async_event_rsp() */
 409                         rc = ISCSI_ERR_BAD_OPCODE;
 410                         break;
 411                 default:
 412                         rc = ISCSI_ERR_BAD_OPCODE;
 413                         break;
 414                 }
 415         } else
 416                 rc = ISCSI_ERR_BAD_ITT;
 417
 418 done:
 419         return rc;
 420 }
 421 EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
 422
 423 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 424                        char *data, int datalen)
 425 {
 426         int rc;
 427
 428         spin_lock(&conn->session->lock);
 429         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
 430         spin_unlock(&conn->session->lock);
 431         return rc;
 432 }
 433 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 434
 435 /* verify itt (itt encoding: age+cid+itt) */
 436 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 437                      uint32_t *ret_itt)
 438 {
 439         struct iscsi_session *session = conn->session;
 440         struct iscsi_cmd_task *ctask;
 441         uint32_t itt;
 442
 443         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
 444                 if ((hdr->itt & ISCSI_AGE_MASK) !=
 445                     (session->age << ISCSI_AGE_SHIFT)) {
 446                         printk(KERN_ERR "iscsi: received itt %x expected "
 447                                 "session age (%x)\n", hdr->itt,
 448                                 session->age & ISCSI_AGE_MASK);
 449                         return ISCSI_ERR_BAD_ITT;
 450                 }
 451
 452                 if ((hdr->itt & ISCSI_CID_MASK) !=
 453                     (conn->id << ISCSI_CID_SHIFT)) {
 454                         printk(KERN_ERR "iscsi: received itt %x, expected "
 455                                 "CID (%x)\n", hdr->itt, conn->id);
 456                         return ISCSI_ERR_BAD_ITT;
 457                 }
 458                 itt = hdr->itt & ISCSI_ITT_MASK;
 459         } else
 460                 itt = hdr->itt;
 461
 462         if (itt < session->cmds_max) {
 463                 ctask = session->cmds[itt];
 464
 465                 if (!ctask->sc) {
 466                         printk(KERN_INFO "iscsi: dropping ctask with "
 467                                "itt 0x%x\n", ctask->itt);
 468                         /* force drop */
 469                         return ISCSI_ERR_NO_SCSI_CMD;
 470                 }
 471
 472                 if (ctask->sc->SCp.phase != session->age) {
 473                         printk(KERN_ERR "iscsi: ctask's session age %d, "
 474                                 "expected %d\n", ctask->sc->SCp.phase,
 475                                 session->age);
 476                         return ISCSI_ERR_SESSION_FAILED;
 477                 }
 478         }
 479
 480         *ret_itt = itt;
 481         return 0;
 482 }
 483 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 484
 485 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 486 {
 487         struct iscsi_session *session = conn->session;
 488         unsigned long flags;
 489
 490         spin_lock_irqsave(&session->lock, flags);
 491         if (session->state == ISCSI_STATE_FAILED) {
 492                 spin_unlock_irqrestore(&session->lock, flags);
 493                 return;
 494         }
 495
 496         if (conn->stop_stage == 0)
 497                 session->state = ISCSI_STATE_FAILED;
 498         spin_unlock_irqrestore(&session->lock, flags);
 499         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 500         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 501         iscsi_conn_error(conn->cls_conn, err);
 502 }
 503 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 504
 505 /**
 506  * iscsi_data_xmit - xmit any command into the scheduled connection
 507  * @conn: iscsi connection
 508  *
 509  * Notes:
 510  *      The function can return -EAGAIN in which case the caller must
 511  *      re-schedule it again later or recover. '0' return code means
 512  *      successful xmit.
 513  **/
 514 static int iscsi_data_xmit(struct iscsi_conn *conn)
 515 {
 516         struct iscsi_transport *tt;
 517         int rc = 0;
 518
 519         if (unlikely(conn->suspend_tx)) {
 520                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 521                 return -ENODATA;
 522         }
 523         tt = conn->session->tt;
 524
 525         /*
 526          * Transmit in the following order:
 527          *
 528          * 1) un-finished xmit (ctask or mtask)
 529          * 2) immediate control PDUs
 530          * 3) write data
 531          * 4) SCSI commands
 532          * 5) non-immediate control PDUs
 533          *
 534          * No need to lock around __kfifo_get as long as
 535          * there's one producer and one consumer.
 536          */
 537
 538         BUG_ON(conn->ctask && conn->mtask);
 539
 540         if (conn->ctask) {
 541                 rc = tt->xmit_cmd_task(conn, conn->ctask);
 542                 if (rc)
 543                         goto again;
 544                 /* done with this in-progress ctask */
 545                 conn->ctask = NULL;
 546         }
 547         if (conn->mtask) {
 548                 rc = tt->xmit_mgmt_task(conn, conn->mtask);
 549                 if (rc)
 550                         goto again;
 551                 /* done with this in-progress mtask */
 552                 conn->mtask = NULL;
 553         }
 554
 555         /* process immediate first */
 556         if (unlikely(__kfifo_len(conn->immqueue))) {
 557                 while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
 558                                    sizeof(void*))) {
 559                         spin_lock_bh(&conn->session->lock);
 560                         list_add_tail(&conn->mtask->running,
 561                                       &conn->mgmt_run_list);
 562                         spin_unlock_bh(&conn->session->lock);
 563                         rc = tt->xmit_mgmt_task(conn, conn->mtask);
 564                         if (rc)
 565                                 goto again;
 566                 }
 567                 /* done with this mtask */
 568                 conn->mtask = NULL;
 569         }
 570
 571         /* process command queue */
 572         spin_lock_bh(&conn->session->lock);
 573         while (!list_empty(&conn->xmitqueue)) {
 574                 /*
 575                  * iscsi tcp may readd the task to the xmitqueue to send
 576                  * write data
 577                  */
 578                 conn->ctask = list_entry(conn->xmitqueue.next,
 579                                          struct iscsi_cmd_task, running);
 580                 conn->ctask->state = ISCSI_TASK_RUNNING;
 581                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
 582                 spin_unlock_bh(&conn->session->lock);
 583
 584                 rc = tt->xmit_cmd_task(conn, conn->ctask);
 585                 if (rc)
 586                         goto again;
 587                 spin_lock_bh(&conn->session->lock);
 588         }
 589         spin_unlock_bh(&conn->session->lock);
 590         /* done with this ctask */
 591         conn->ctask = NULL;
 592
 593         /* process the rest control plane PDUs, if any */
 594         if (unlikely(__kfifo_len(conn->mgmtqueue))) {
 595                 while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
 596                                    sizeof(void*))) {
 597                         spin_lock_bh(&conn->session->lock);
 598                         list_add_tail(&conn->mtask->running,
 599                                       &conn->mgmt_run_list);
 600                         spin_unlock_bh(&conn->session->lock);
 601                         rc = tt->xmit_mgmt_task(conn, conn->mtask);
 602                         if (rc)
 603                                 goto again;
 604                 }
 605                 /* done with this mtask */
 606                 conn->mtask = NULL;
 607         }
 608
 609         return -ENODATA;
 610
 611 again:
 612         if (unlikely(conn->suspend_tx))
 613                 return -ENODATA;
 614
 615         return rc;
 616 }
 617
 618 static void iscsi_xmitworker(void *data)
 619 {
 620         struct iscsi_conn *conn = data;
 621         int rc;
 622         /*
 623          * serialize Xmit worker on a per-connection basis.
 624          */
 625         mutex_lock(&conn->xmitmutex);
 626         do {
 627                 rc = iscsi_data_xmit(conn);
 628         } while (rc >= 0 || rc == -EAGAIN);
 629         mutex_unlock(&conn->xmitmutex);
 630 }
 631
 632 enum {
 633         FAILURE_BAD_HOST = 1,
 634         FAILURE_SESSION_FAILED,
 635         FAILURE_SESSION_FREED,
 636         FAILURE_WINDOW_CLOSED,
 637         FAILURE_SESSION_TERMINATE,
 638         FAILURE_SESSION_IN_RECOVERY,
 639         FAILURE_SESSION_RECOVERY_TIMEOUT,
 640 };
 641
 642 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 643 {
 644         struct Scsi_Host *host;
 645         int reason = 0;
 646         struct iscsi_session *session;
 647         struct iscsi_conn *conn;
 648         struct iscsi_cmd_task *ctask = NULL;
 649
 650         sc->scsi_done = done;
 651         sc->result = 0;
 652
 653         host = sc->device->host;
 654         session = iscsi_hostdata(host->hostdata);
 655
 656         spin_lock(&session->lock);
 657
 658         /*
 659          * ISCSI_STATE_FAILED is a temp. state. The recovery
 660          * code will decide what is best to do with command queued
 661          * during this time
 662          */
 663         if (session->state != ISCSI_STATE_LOGGED_IN &&
 664             session->state != ISCSI_STATE_FAILED) {
 665                 /*
 666                  * to handle the race between when we set the recovery state
 667                  * and block the session we requeue here (commands could
 668                  * be entering our queuecommand while a block is starting
 669                  * up because the block code is not locked)
 670                  */
 671                 if (session->state == ISCSI_STATE_IN_RECOVERY) {
 672                         reason = FAILURE_SESSION_IN_RECOVERY;
 673                         goto reject;
 674                 }
 675
 676                 if (session->state == ISCSI_STATE_RECOVERY_FAILED)
 677                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
 678                 else if (session->state == ISCSI_STATE_TERMINATE)
 679                         reason = FAILURE_SESSION_TERMINATE;
 680                 else
 681                         reason = FAILURE_SESSION_FREED;
 682                 goto fault;
 683         }
 684
 685         /*
 686          * Check for iSCSI window and take care of CmdSN wrap-around
 687          */
 688         if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
 689                 reason = FAILURE_WINDOW_CLOSED;
 690                 goto reject;
 691         }
 692
 693         conn = session->leadconn;
 694
 695         __kfifo_get(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
 696         sc->SCp.phase = session->age;
 697         sc->SCp.ptr = (char *)ctask;
 698
 699         ctask->state = ISCSI_TASK_PENDING;
 700         ctask->mtask = NULL;
 701         ctask->conn = conn;
 702         ctask->sc = sc;
 703         INIT_LIST_HEAD(&ctask->running);
 704         ctask->total_length = sc->request_bufflen;
 705         iscsi_prep_scsi_cmd_pdu(ctask);
 706
 707         session->tt->init_cmd_task(ctask);
 708
 709         list_add_tail(&ctask->running, &conn->xmitqueue);
 710         debug_scsi(
 711                "ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n",
 712                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
 713                 conn->id, (long)sc, ctask->itt, sc->request_bufflen,
 714                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 715         spin_unlock(&session->lock);
 716
 717         scsi_queue_work(host, &conn->xmitwork);
 718         return 0;
 719
 720 reject:
 721         spin_unlock(&session->lock);
 722         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
 723         return SCSI_MLQUEUE_HOST_BUSY;
 724
 725 fault:
 726         spin_unlock(&session->lock);
 727         printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
 728                sc->cmnd[0], reason);
 729         sc->result = (DID_NO_CONNECT << 16);
 730         sc->resid = sc->request_bufflen;
 731         sc->scsi_done(sc);
 732         return 0;
 733 }
 734 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
 735
 736 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
 737 {
 738         if (depth > ISCSI_MAX_CMD_PER_LUN)
 739                 depth = ISCSI_MAX_CMD_PER_LUN;
 740         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 741         return sdev->queue_depth;
 742 }
 743 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
 744
 745 static int
 746 iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 747                         char *data, uint32_t data_size)
 748 {
 749         struct iscsi_session *session = conn->session;
 750         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 751         struct iscsi_mgmt_task *mtask;
 752
 753         spin_lock_bh(&session->lock);
 754         if (session->state == ISCSI_STATE_TERMINATE) {
 755                 spin_unlock_bh(&session->lock);
 756                 return -EPERM;
 757         }
 758         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
 759             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 760                 /*
 761                  * Login and Text are sent serially, in
 762                  * request-followed-by-response sequence.
 763                  * Same mtask can be used. Same ITT must be used.
 764                  * Note that login_mtask is preallocated at conn_create().
 765                  */
 766                 mtask = conn->login_mtask;
 767         else {
 768                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 769                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 770
 771                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 772                 if (!__kfifo_get(session->mgmtpool.queue,
 773                                  (void*)&mtask, sizeof(void*))) {
 774                         spin_unlock_bh(&session->lock);
 775                         return -ENOSPC;
 776                 }
 777         }
 778
 779         /*
 780          * pre-format CmdSN for outgoing PDU.
 781          */
 782         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
 783                 hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) |
 784                            (session->age << ISCSI_AGE_SHIFT);
 785                 nop->cmdsn = cpu_to_be32(session->cmdsn);
 786                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 787                     !(hdr->opcode & ISCSI_OP_IMMEDIATE))
 788                         session->cmdsn++;
 789         } else
 790                 /* do not advance CmdSN */
 791                 nop->cmdsn = cpu_to_be32(session->cmdsn);
 792
 793         if (data_size) {
 794                 memcpy(mtask->data, data, data_size);
 795                 mtask->data_count = data_size;
 796         } else
 797                 mtask->data_count = 0;
 798
 799         INIT_LIST_HEAD(&mtask->running);
 800         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
 801         if (session->tt->init_mgmt_task)
 802                 session->tt->init_mgmt_task(conn, mtask, data, data_size);
 803         spin_unlock_bh(&session->lock);
 804
 805         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 806                    hdr->opcode, hdr->itt, data_size);
 807
 808         /*
 809          * since send_pdu() could be called at least from two contexts,
 810          * we need to serialize __kfifo_put, so we don't have to take
 811          * additional lock on fast data-path
 812          */
 813         if (hdr->opcode & ISCSI_OP_IMMEDIATE)
 814                 __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
 815         else
 816                 __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
 817
 818         scsi_queue_work(session->host, &conn->xmitwork);
 819         return 0;
 820 }
 821
 822 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 823                         char *data, uint32_t data_size)
 824 {
 825         struct iscsi_conn *conn = cls_conn->dd_data;
 826         int rc;
 827
 828         mutex_lock(&conn->xmitmutex);
 829         rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
 830         mutex_unlock(&conn->xmitmutex);
 831
 832         return rc;
 833 }
 834 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 835
 836 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
 837 {
 838         struct iscsi_session *session = class_to_transport_session(cls_session);
 839         struct iscsi_conn *conn = session->leadconn;
 840
 841         spin_lock_bh(&session->lock);
 842         if (session->state != ISCSI_STATE_LOGGED_IN) {
 843                 session->state = ISCSI_STATE_RECOVERY_FAILED;
 844                 if (conn)
 845                         wake_up(&conn->ehwait);
 846         }
 847         spin_unlock_bh(&session->lock);
 848 }
 849 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
 850
 851 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
 852 {
 853         struct Scsi_Host *host = sc->device->host;
 854         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
 855         struct iscsi_conn *conn = session->leadconn;
 856         int fail_session = 0;
 857
 858         spin_lock_bh(&session->lock);
 859         if (session->state == ISCSI_STATE_TERMINATE) {
 860 failed:
 861                 debug_scsi("failing host reset: session terminated "
 862                            "[CID %d age %d]", conn->id, session->age);
 863                 spin_unlock_bh(&session->lock);
 864                 return FAILED;
 865         }
 866
 867         if (sc->SCp.phase == session->age) {
 868                 debug_scsi("failing connection CID %d due to SCSI host reset",
 869                            conn->id);
 870                 fail_session = 1;
 871         }
 872         spin_unlock_bh(&session->lock);
 873
 874         /*
 875          * we drop the lock here but the leadconn cannot be destoyed while
 876          * we are in the scsi eh
 877          */
 878         if (fail_session)
 879                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 880
 881         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
 882         wait_event_interruptible(conn->ehwait,
 883                                  session->state == ISCSI_STATE_TERMINATE ||
 884                                  session->state == ISCSI_STATE_LOGGED_IN ||
 885                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
 886         if (signal_pending(current))
 887                 flush_signals(current);
 888
 889         spin_lock_bh(&session->lock);
 890         if (session->state == ISCSI_STATE_LOGGED_IN)
 891                 printk(KERN_INFO "iscsi: host reset succeeded\n");
 892         else
 893                 goto failed;
 894         spin_unlock_bh(&session->lock);
 895
 896         return SUCCESS;
 897 }
 898 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
 899
 900 static void iscsi_tmabort_timedout(unsigned long data)
 901 {
 902         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
 903         struct iscsi_conn *conn = ctask->conn;
 904         struct iscsi_session *session = conn->session;
 905
 906         spin_lock(&session->lock);
 907         if (conn->tmabort_state == TMABORT_INITIAL) {
 908                 conn->tmabort_state = TMABORT_TIMEDOUT;
 909                 debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
 910                         ctask->sc, ctask->itt);
 911                 /* unblock eh_abort() */
 912                 wake_up(&conn->ehwait);
 913         }
 914         spin_unlock(&session->lock);
 915 }
 916
 917 /* must be called with the mutex lock */
 918 static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
 919                                  struct iscsi_cmd_task *ctask)
 920 {
 921         struct iscsi_conn *conn = ctask->conn;
 922         struct iscsi_session *session = conn->session;
 923         struct iscsi_tm *hdr = &conn->tmhdr;
 924         int rc;
 925
 926         /*
 927          * ctask timed out but session is OK requests must be serialized.
 928          */
 929         memset(hdr, 0, sizeof(struct iscsi_tm));
 930         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
 931         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
 932         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 933         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
 934         hdr->rtt = ctask->hdr->itt;
 935         hdr->refcmdsn = ctask->hdr->cmdsn;
 936
 937         rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
 938                                      NULL, 0);
 939         if (rc) {
 940                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 941                 debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc);
 942                 return rc;
 943         }
 944
 945         debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
 946
 947         spin_lock_bh(&session->lock);
 948         ctask->mtask = (struct iscsi_mgmt_task *)
 949                         session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) -
 950                                         ISCSI_MGMT_ITT_OFFSET];
 951
 952         if (conn->tmabort_state == TMABORT_INITIAL) {
 953                 conn->tmfcmd_pdus_cnt++;
 954                 conn->tmabort_timer.expires = 10*HZ + jiffies;
 955                 conn->tmabort_timer.function = iscsi_tmabort_timedout;
 956                 conn->tmabort_timer.data = (unsigned long)ctask;
 957                 add_timer(&conn->tmabort_timer);
 958                 debug_scsi("abort set timeout [itt 0x%x]", ctask->itt);
 959         }
 960         spin_unlock_bh(&session->lock);
 961         mutex_unlock(&conn->xmitmutex);
 962
 963         /*
 964          * block eh thread until:
 965          *
 966          * 1) abort response
 967          * 2) abort timeout
 968          * 3) session is terminated or restarted or userspace has
 969          * given up on recovery
 970          */
 971         wait_event_interruptible(conn->ehwait,
 972                                  sc->SCp.phase != session->age ||
 973                                  session->state != ISCSI_STATE_LOGGED_IN ||
 974                                  conn->tmabort_state != TMABORT_INITIAL);
 975         if (signal_pending(current))
 976                 flush_signals(current);
 977         del_timer_sync(&conn->tmabort_timer);
 978
 979         mutex_lock(&conn->xmitmutex);
 980         return 0;
 981 }
 982
 983 /*
 984  * xmit mutex and session lock must be held
 985  */
 986 static struct iscsi_mgmt_task *
 987 iscsi_remove_mgmt_task(struct kfifo *fifo, uint32_t itt)
 988 {
 989         int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);
 990         struct iscsi_mgmt_task *task;
 991
 992         debug_scsi("searching %d tasks\n", nr_tasks);
 993
 994         for (i = 0; i < nr_tasks; i++) {
 995                 __kfifo_get(fifo, (void*)&task, sizeof(void*));
 996                 debug_scsi("check task %u\n", task->itt);
 997
 998                 if (task->itt == itt) {
 999                         debug_scsi("matched task\n");
1000                         return task;
1001                 }
1002
1003                 __kfifo_put(fifo, (void*)&task, sizeof(void*));
1004         }
1005         return NULL;
1006 }
1007
1008 static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
1009 {
1010         struct iscsi_conn *conn = ctask->conn;
1011         struct iscsi_session *session = conn->session;
1012
1013         if (!ctask->mtask)
1014                 return -EINVAL;
1015
1016         if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
1017                 list_del(&ctask->mtask->running);
1018         __kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
1019                     sizeof(void*));
1020         ctask->mtask = NULL;
1021         return 0;
1022 }
1023
1024 /*
1025  * session lock and xmitmutex must be held
1026  */
1027 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1028                          int err)
1029 {
1030         struct scsi_cmnd *sc;
1031
1032         conn->session->tt->cleanup_cmd_task(conn, ctask);
1033         iscsi_ctask_mtask_cleanup(ctask);
1034
1035         sc = ctask->sc;
1036         if (!sc)
1037                 return;
1038         sc->result = err;
1039         sc->resid = sc->request_bufflen;
1040         iscsi_complete_command(conn->session, ctask);
1041 }
1042
1043 int iscsi_eh_abort(struct scsi_cmnd *sc)
1044 {
1045         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1046         struct iscsi_conn *conn = ctask->conn;
1047         struct iscsi_session *session = conn->session;
1048         int rc;
1049
1050         conn->eh_abort_cnt++;
1051         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1052
1053         mutex_lock(&conn->xmitmutex);
1054         spin_lock_bh(&session->lock);
1055
1056         /*
1057          * If we are not logged in or we have started a new session
1058          * then let the host reset code handle this
1059          */
1060         if (session->state != ISCSI_STATE_LOGGED_IN ||
1061             sc->SCp.phase != session->age)
1062                 goto failed;
1063
1064         /* ctask completed before time out */
1065         if (!ctask->sc)
1066                 goto success;
1067
1068         /* what should we do here ? */
1069         if (conn->ctask == ctask) {
1070                 printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. "
1071                        "Failing abort\n", sc, ctask->itt);
1072                 goto failed;
1073         }
1074
1075         if (ctask->state == ISCSI_TASK_PENDING)
1076                 goto success;
1077
1078         conn->tmabort_state = TMABORT_INITIAL;
1079
1080         spin_unlock_bh(&session->lock);
1081         rc = iscsi_exec_abort_task(sc, ctask);
1082         spin_lock_bh(&session->lock);
1083
1084         iscsi_ctask_mtask_cleanup(ctask);
1085         if (rc || sc->SCp.phase != session->age ||
1086             session->state != ISCSI_STATE_LOGGED_IN)
1087                 goto failed;
1088
1089         /* ctask completed before tmf abort response */
1090         if (!ctask->sc) {
1091                 debug_scsi("sc completed while abort in progress\n");
1092                 goto success;
1093         }
1094
1095         if (conn->tmabort_state != TMABORT_SUCCESS) {
1096                 spin_unlock_bh(&session->lock);
1097                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1098                 spin_lock_bh(&session->lock);
1099                 goto failed;
1100         }
1101
1102 success:
1103         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1104         spin_unlock_bh(&session->lock);
1105
1106         /*
1107          * clean up task if aborted. we have the xmitmutex so grab
1108          * the recv lock as a writer
1109          */
1110         write_lock_bh(conn->recv_lock);
1111         spin_lock(&session->lock);
1112         fail_command(conn, ctask, DID_ABORT << 16);
1113         spin_unlock(&session->lock);
1114         write_unlock_bh(conn->recv_lock);
1115
1116         mutex_unlock(&conn->xmitmutex);
1117         return SUCCESS;
1118
1119 failed:
1120         spin_unlock_bh(&session->lock);
1121         mutex_unlock(&conn->xmitmutex);
1122
1123         debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1124         return FAILED;
1125 }
1126 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1127
1128 int
1129 iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
1130 {
1131         int i;
1132
1133         *items = kmalloc(max * sizeof(void*), GFP_KERNEL);
1134         if (*items == NULL)
1135                 return -ENOMEM;
1136
1137         q->max = max;
1138         q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
1139         if (q->pool == NULL) {
1140                 kfree(*items);
1141                 return -ENOMEM;
1142         }
1143
1144         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1145                               GFP_KERNEL, NULL);
1146         if (q->queue == ERR_PTR(-ENOMEM)) {
1147                 kfree(q->pool);
1148                 kfree(*items);
1149                 return -ENOMEM;
1150         }
1151
1152         for (i = 0; i < max; i++) {
1153                 q->pool[i] = kmalloc(item_size, GFP_KERNEL);
1154                 if (q->pool[i] == NULL) {
1155                         int j;
1156
1157                         for (j = 0; j < i; j++)
1158                                 kfree(q->pool[j]);
1159
1160                         kfifo_free(q->queue);
1161                         kfree(q->pool);
1162                         kfree(*items);
1163                         return -ENOMEM;
1164                 }
1165                 memset(q->pool[i], 0, item_size);
1166                 (*items)[i] = q->pool[i];
1167                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1168         }
1169         return 0;
1170 }
1171 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1172
1173 void iscsi_pool_free(struct iscsi_queue *q, void **items)
1174 {
1175         int i;
1176
1177         for (i = 0; i < q->max; i++)
1178                 kfree(items[i]);
1179         kfree(q->pool);
1180         kfree(items);
1181 }
1182 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1183
1184 /*
1185  * iSCSI Session's hostdata organization:
1186  *
1187  *    *------------------* <== hostdata_session(host->hostdata)
1188  *    | ptr to class sess|
1189  *    |------------------| <== iscsi_hostdata(host->hostdata)
1190  *    | iscsi_session    |
1191  *    *------------------*
1192  */
1193
1194 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1195                                  _sz % sizeof(unsigned long))
1196
1197 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1198
1199 /**
1200  * iscsi_session_setup - create iscsi cls session and host and session
1201  * @scsit: scsi transport template
1202  * @iscsit: iscsi transport template
1203  * @initial_cmdsn: initial CmdSN
1204  * @hostno: host no allocated
1205  *
1206  * This can be used by software iscsi_transports that allocate
1207  * a session per scsi host.
1208  **/
1209 struct iscsi_cls_session *
1210 iscsi_session_setup(struct iscsi_transport *iscsit,
1211                     struct scsi_transport_template *scsit,
1212                     int cmd_task_size, int mgmt_task_size,
1213                     uint32_t initial_cmdsn, uint32_t *hostno)
1214 {
1215         struct Scsi_Host *shost;
1216         struct iscsi_session *session;
1217         struct iscsi_cls_session *cls_session;
1218         int cmd_i;
1219
1220         shost = scsi_host_alloc(iscsit->host_template,
1221                                 hostdata_privsize(sizeof(*session)));
1222         if (!shost)
1223                 return NULL;
1224
1225         shost->max_id = 1;
1226         shost->max_channel = 0;
1227         shost->max_lun = iscsit->max_lun;
1228         shost->max_cmd_len = iscsit->max_cmd_len;
1229         shost->transportt = scsit;
1230         shost->transportt->create_work_queue = 1;
1231         *hostno = shost->host_no;
1232
1233         session = iscsi_hostdata(shost->hostdata);
1234         memset(session, 0, sizeof(struct iscsi_session));
1235         session->host = shost;
1236         session->state = ISCSI_STATE_FREE;
1237         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1238         session->cmds_max = ISCSI_XMIT_CMDS_MAX;
1239         session->cmdsn = initial_cmdsn;
1240         session->exp_cmdsn = initial_cmdsn + 1;
1241         session->max_cmdsn = initial_cmdsn + 1;
1242         session->max_r2t = 1;
1243         session->tt = iscsit;
1244
1245         /* initialize SCSI PDU commands pool */
1246         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1247                             (void***)&session->cmds,
1248                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1249                 goto cmdpool_alloc_fail;
1250
1251         /* pre-format cmds pool with ITT */
1252         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1253                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1254
1255                 if (cmd_task_size)
1256                         ctask->dd_data = &ctask[1];
1257                 ctask->itt = cmd_i;
1258                 INIT_LIST_HEAD(&ctask->running);
1259         }
1260
1261         spin_lock_init(&session->lock);
1262         INIT_LIST_HEAD(&session->connections);
1263
1264         /* initialize immediate command pool */
1265         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1266                            (void***)&session->mgmt_cmds,
1267                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1268                 goto mgmtpool_alloc_fail;
1269
1270
1271         /* pre-format immediate cmds pool with ITT */
1272         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1273                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1274
1275                 if (mgmt_task_size)
1276                         mtask->dd_data = &mtask[1];
1277                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1278                 INIT_LIST_HEAD(&mtask->running);
1279         }
1280
1281         if (scsi_add_host(shost, NULL))
1282                 goto add_host_fail;
1283
1284         if (!try_module_get(iscsit->owner))
1285                 goto cls_session_fail;
1286
1287         cls_session = iscsi_create_session(shost, iscsit, 0);
1288         if (!cls_session)
1289                 goto module_put;
1290         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1291
1292         return cls_session;
1293
1294 module_put:
1295         module_put(iscsit->owner);
1296 cls_session_fail:
1297         scsi_remove_host(shost);
1298 add_host_fail:
1299         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1300 mgmtpool_alloc_fail:
1301         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1302 cmdpool_alloc_fail:
1303         scsi_host_put(shost);
1304         return NULL;
1305 }
1306 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1307
1308 /**
1309  * iscsi_session_teardown - destroy session, host, and cls_session
1310  * shost: scsi host
1311  *
1312  * This can be used by software iscsi_transports that allocate
1313  * a session per scsi host.
1314  **/
1315 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1316 {
1317         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1318         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1319
1320         scsi_remove_host(shost);
1321
1322         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1323         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1324
1325         iscsi_destroy_session(cls_session);
1326         scsi_host_put(shost);
1327         module_put(cls_session->transport->owner);
1328 }
1329 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1330
1331 /**
1332  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1333  * @cls_session: iscsi_cls_session
1334  * @conn_idx: cid
1335  **/
1336 struct iscsi_cls_conn *
1337 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1338 {
1339         struct iscsi_session *session = class_to_transport_session(cls_session);
1340         struct iscsi_conn *conn;
1341         struct iscsi_cls_conn *cls_conn;
1342         char *data;
1343
1344         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1345         if (!cls_conn)
1346                 return NULL;
1347         conn = cls_conn->dd_data;
1348         memset(conn, 0, sizeof(*conn));
1349
1350         conn->session = session;
1351         conn->cls_conn = cls_conn;
1352         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1353         conn->id = conn_idx;
1354         conn->exp_statsn = 0;
1355         conn->tmabort_state = TMABORT_INITIAL;
1356         INIT_LIST_HEAD(&conn->run_list);
1357         INIT_LIST_HEAD(&conn->mgmt_run_list);
1358         INIT_LIST_HEAD(&conn->xmitqueue);
1359
1360         /* initialize general immediate & non-immediate PDU commands queue */
1361         conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1362                                         GFP_KERNEL, NULL);
1363         if (conn->immqueue == ERR_PTR(-ENOMEM))
1364                 goto immqueue_alloc_fail;
1365
1366         conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1367                                         GFP_KERNEL, NULL);
1368         if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
1369                 goto mgmtqueue_alloc_fail;
1370
1371         INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
1372
1373         /* allocate login_mtask used for the login/text sequences */
1374         spin_lock_bh(&session->lock);
1375         if (!__kfifo_get(session->mgmtpool.queue,
1376                          (void*)&conn->login_mtask,
1377                          sizeof(void*))) {
1378                 spin_unlock_bh(&session->lock);
1379                 goto login_mtask_alloc_fail;
1380         }
1381         spin_unlock_bh(&session->lock);
1382
1383         data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
1384         if (!data)
1385                 goto login_mtask_data_alloc_fail;
1386         conn->login_mtask->data = data;
1387
1388         init_timer(&conn->tmabort_timer);
1389         mutex_init(&conn->xmitmutex);
1390         init_waitqueue_head(&conn->ehwait);
1391
1392         return cls_conn;
1393
1394 login_mtask_data_alloc_fail:
1395         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1396                     sizeof(void*));
1397 login_mtask_alloc_fail:
1398         kfifo_free(conn->mgmtqueue);
1399 mgmtqueue_alloc_fail:
1400         kfifo_free(conn->immqueue);
1401 immqueue_alloc_fail:
1402         iscsi_destroy_conn(cls_conn);
1403         return NULL;
1404 }
1405 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1406
1407 /**
1408  * iscsi_conn_teardown - teardown iscsi connection
1409  * cls_conn: iscsi class connection
1410  *
1411  * TODO: we may need to make this into a two step process
1412  * like scsi-mls remove + put host
1413  */
1414 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1415 {
1416         struct iscsi_conn *conn = cls_conn->dd_data;
1417         struct iscsi_session *session = conn->session;
1418         unsigned long flags;
1419
1420         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1421         mutex_lock(&conn->xmitmutex);
1422         if (conn->c_stage == ISCSI_CONN_INITIAL_STAGE) {
1423                 if (session->tt->suspend_conn_recv)
1424                         session->tt->suspend_conn_recv(conn);
1425
1426                 session->tt->terminate_conn(conn);
1427         }
1428
1429         spin_lock_bh(&session->lock);
1430         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1431         if (session->leadconn == conn) {
1432                 /*
1433                  * leading connection? then give up on recovery.
1434                  */
1435                 session->state = ISCSI_STATE_TERMINATE;
1436                 wake_up(&conn->ehwait);
1437         }
1438         spin_unlock_bh(&session->lock);
1439
1440         mutex_unlock(&conn->xmitmutex);
1441
1442         /*
1443          * Block until all in-progress commands for this connection
1444          * time out or fail.
1445          */
1446         for (;;) {
1447                 spin_lock_irqsave(session->host->host_lock, flags);
1448                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1449                         spin_unlock_irqrestore(session->host->host_lock, flags);
1450                         break;
1451                 }
1452                 spin_unlock_irqrestore(session->host->host_lock, flags);
1453                 msleep_interruptible(500);
1454                 printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
1455                        "host_failed %d\n", session->host->host_busy,
1456                        session->host->host_failed);
1457                 /*
1458                  * force eh_abort() to unblock
1459                  */
1460                 wake_up(&conn->ehwait);
1461         }
1462
1463         spin_lock_bh(&session->lock);
1464         kfree(conn->login_mtask->data);
1465         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1466                     sizeof(void*));
1467         list_del(&conn->item);
1468         if (list_empty(&session->connections))
1469                 session->leadconn = NULL;
1470         if (session->leadconn && session->leadconn == conn)
1471                 session->leadconn = container_of(session->connections.next,
1472                         struct iscsi_conn, item);
1473
1474         if (session->leadconn == NULL)
1475                 /* no connections exits.. reset sequencing */
1476                 session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
1477         spin_unlock_bh(&session->lock);
1478
1479         kfifo_free(conn->immqueue);
1480         kfifo_free(conn->mgmtqueue);
1481
1482         iscsi_destroy_conn(cls_conn);
1483 }
1484 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1485
1486 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1487 {
1488         struct iscsi_conn *conn = cls_conn->dd_data;
1489         struct iscsi_session *session = conn->session;
1490
1491         if (session == NULL) {
1492                 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1493                 return -EPERM;
1494         }
1495
1496         spin_lock_bh(&session->lock);
1497         conn->c_stage = ISCSI_CONN_STARTED;
1498         session->state = ISCSI_STATE_LOGGED_IN;
1499
1500         switch(conn->stop_stage) {
1501         case STOP_CONN_RECOVER:
1502                 /*
1503                  * unblock eh_abort() if it is blocked. re-try all
1504                  * commands after successful recovery
1505                  */
1506                 conn->stop_stage = 0;
1507                 conn->tmabort_state = TMABORT_INITIAL;
1508                 session->age++;
1509                 spin_unlock_bh(&session->lock);
1510
1511                 iscsi_unblock_session(session_to_cls(session));
1512                 wake_up(&conn->ehwait);
1513                 return 0;
1514         case STOP_CONN_TERM:
1515                 conn->stop_stage = 0;
1516                 break;
1517         default:
1518                 break;
1519         }
1520         spin_unlock_bh(&session->lock);
1521
1522         return 0;
1523 }
1524 EXPORT_SYMBOL_GPL(iscsi_conn_start);
1525
1526 static void
1527 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
1528 {
1529         struct iscsi_mgmt_task *mtask, *tmp;
1530
1531         /* handle pending */
1532         while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
1533                __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
1534                 if (mtask == conn->login_mtask)
1535                         continue;
1536                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
1537                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1538                             sizeof(void*));
1539         }
1540
1541         /* handle running */
1542         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
1543                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
1544                 list_del(&mtask->running);
1545
1546                 if (mtask == conn->login_mtask)
1547                         continue;
1548                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1549                            sizeof(void*));
1550         }
1551
1552         conn->mtask = NULL;
1553 }
1554
1555 /* Fail commands. Mutex and session lock held and recv side suspended */
1556 static void fail_all_commands(struct iscsi_conn *conn)
1557 {
1558         struct iscsi_cmd_task *ctask, *tmp;
1559
1560         /* flush pending */
1561         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1562                 debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
1563                            ctask->itt);
1564                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1565         }
1566
1567         /* fail all other running */
1568         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1569                 debug_scsi("failing in progress sc %p itt 0x%x\n",
1570                            ctask->sc, ctask->itt);
1571                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1572         }
1573
1574         conn->ctask = NULL;
1575 }
1576
1577 static void iscsi_start_session_recovery(struct iscsi_session *session,
1578                                          struct iscsi_conn *conn, int flag)
1579 {
1580         int old_stop_stage;
1581
1582         spin_lock_bh(&session->lock);
1583         if (conn->stop_stage == STOP_CONN_TERM) {
1584                 spin_unlock_bh(&session->lock);
1585                 return;
1586         }
1587
1588         /*
1589          * When this is called for the in_login state, we only want to clean
1590          * up the login task and connection. We do not need to block and set
1591          * the recovery state again
1592          */
1593         if (flag == STOP_CONN_TERM)
1594                 session->state = ISCSI_STATE_TERMINATE;
1595         else if (conn->stop_stage != STOP_CONN_RECOVER)
1596                 session->state = ISCSI_STATE_IN_RECOVERY;
1597
1598         old_stop_stage = conn->stop_stage;
1599         conn->stop_stage = flag;
1600         conn->c_stage = ISCSI_CONN_STOPPED;
1601         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1602         spin_unlock_bh(&session->lock);
1603
1604         if (session->tt->suspend_conn_recv)
1605                 session->tt->suspend_conn_recv(conn);
1606
1607         mutex_lock(&conn->xmitmutex);
1608         /*
1609          * for connection level recovery we should not calculate
1610          * header digest. conn->hdr_size used for optimization
1611          * in hdr_extract() and will be re-negotiated at
1612          * set_param() time.
1613          */
1614         if (flag == STOP_CONN_RECOVER) {
1615                 conn->hdrdgst_en = 0;
1616                 conn->datadgst_en = 0;
1617                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
1618                     old_stop_stage != STOP_CONN_RECOVER) {
1619                         debug_scsi("blocking session\n");
1620                         iscsi_block_session(session_to_cls(session));
1621                 }
1622         }
1623
1624         session->tt->terminate_conn(conn);
1625         /*
1626          * flush queues.
1627          */
1628         spin_lock_bh(&session->lock);
1629         fail_all_commands(conn);
1630         flush_control_queues(session, conn);
1631         spin_unlock_bh(&session->lock);
1632
1633         mutex_unlock(&conn->xmitmutex);
1634 }
1635
1636 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1637 {
1638         struct iscsi_conn *conn = cls_conn->dd_data;
1639         struct iscsi_session *session = conn->session;
1640
1641         switch (flag) {
1642         case STOP_CONN_RECOVER:
1643         case STOP_CONN_TERM:
1644                 iscsi_start_session_recovery(session, conn, flag);
1645                 break;
1646         default:
1647                 printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
1648         }
1649 }
1650 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
1651
1652 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
1653                     struct iscsi_cls_conn *cls_conn, int is_leading)
1654 {
1655         struct iscsi_session *session = class_to_transport_session(cls_session);
1656         struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = cls_conn->dd_data;
1657
1658         /* lookup for existing connection */
1659         spin_lock_bh(&session->lock);
1660         list_for_each_entry(tmp, &session->connections, item) {
1661                 if (tmp == conn) {
1662                         if (conn->c_stage != ISCSI_CONN_STOPPED ||
1663                             conn->stop_stage == STOP_CONN_TERM) {
1664                                 printk(KERN_ERR "iscsi: can't bind "
1665                                        "non-stopped connection (%d:%d)\n",
1666                                        conn->c_stage, conn->stop_stage);
1667                                 spin_unlock_bh(&session->lock);
1668                                 return -EIO;
1669                         }
1670                         break;
1671                 }
1672         }
1673         if (tmp != conn) {
1674                 /* bind new iSCSI connection to session */
1675                 conn->session = session;
1676                 list_add(&conn->item, &session->connections);
1677         }
1678         spin_unlock_bh(&session->lock);
1679
1680         if (is_leading)
1681                 session->leadconn = conn;
1682
1683         /*
1684          * Unblock xmitworker(), Login Phase will pass through.
1685          */
1686         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1687         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1688         return 0;
1689 }
1690 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
1691
1692
1693 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
1694                     enum iscsi_param param, char *buf, int buflen)
1695 {
1696         struct iscsi_conn *conn = cls_conn->dd_data;
1697         struct iscsi_session *session = conn->session;
1698         uint32_t value;
1699
1700         switch(param) {
1701         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1702                 sscanf(buf, "%d", &conn->max_recv_dlength);
1703                 break;
1704         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1705                 sscanf(buf, "%d", &conn->max_xmit_dlength);
1706                 break;
1707         case ISCSI_PARAM_HDRDGST_EN:
1708                 sscanf(buf, "%d", &conn->hdrdgst_en);
1709                 break;
1710         case ISCSI_PARAM_DATADGST_EN:
1711                 sscanf(buf, "%d", &conn->datadgst_en);
1712                 break;
1713         case ISCSI_PARAM_INITIAL_R2T_EN:
1714                 sscanf(buf, "%d", &session->initial_r2t_en);
1715                 break;
1716         case ISCSI_PARAM_MAX_R2T:
1717                 sscanf(buf, "%d", &session->max_r2t);
1718                 break;
1719         case ISCSI_PARAM_IMM_DATA_EN:
1720                 sscanf(buf, "%d", &session->imm_data_en);
1721                 break;
1722         case ISCSI_PARAM_FIRST_BURST:
1723                 sscanf(buf, "%d", &session->first_burst);
1724                 break;
1725         case ISCSI_PARAM_MAX_BURST:
1726                 sscanf(buf, "%d", &session->max_burst);
1727                 break;
1728         case ISCSI_PARAM_PDU_INORDER_EN:
1729                 sscanf(buf, "%d", &session->pdu_inorder_en);
1730                 break;
1731         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1732                 sscanf(buf, "%d", &session->dataseq_inorder_en);
1733                 break;
1734         case ISCSI_PARAM_ERL:
1735                 sscanf(buf, "%d", &session->erl);
1736                 break;
1737         case ISCSI_PARAM_IFMARKER_EN:
1738                 sscanf(buf, "%d", &value);
1739                 BUG_ON(value);
1740                 break;
1741         case ISCSI_PARAM_OFMARKER_EN:
1742                 sscanf(buf, "%d", &value);
1743                 BUG_ON(value);
1744                 break;
1745         case ISCSI_PARAM_EXP_STATSN:
1746                 sscanf(buf, "%u", &conn->exp_statsn);
1747                 break;
1748         case ISCSI_PARAM_TARGET_NAME:
1749                 /* this should not change between logins */
1750                 if (session->targetname)
1751                         break;
1752
1753                 session->targetname = kstrdup(buf, GFP_KERNEL);
1754                 if (!session->targetname)
1755                         return -ENOMEM;
1756                 break;
1757         case ISCSI_PARAM_TPGT:
1758                 sscanf(buf, "%d", &session->tpgt);
1759                 break;
1760         case ISCSI_PARAM_PERSISTENT_PORT:
1761                 sscanf(buf, "%d", &conn->persistent_port);
1762                 break;
1763         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1764                 /*
1765                  * this is the address returned in discovery so it should
1766                  * not change between logins.
1767                  */
1768                 if (conn->persistent_address)
1769                         break;
1770
1771                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
1772                 if (!conn->persistent_address)
1773                         return -ENOMEM;
1774                 break;
1775         default:
1776                 return -ENOSYS;
1777         }
1778
1779         return 0;
1780 }
1781 EXPORT_SYMBOL_GPL(iscsi_set_param);
1782
1783 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
1784                             enum iscsi_param param, char *buf)
1785 {
1786         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1787         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1788         int len;
1789
1790         switch(param) {
1791         case ISCSI_PARAM_INITIAL_R2T_EN:
1792                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
1793                 break;
1794         case ISCSI_PARAM_MAX_R2T:
1795                 len = sprintf(buf, "%hu\n", session->max_r2t);
1796                 break;
1797         case ISCSI_PARAM_IMM_DATA_EN:
1798                 len = sprintf(buf, "%d\n", session->imm_data_en);
1799                 break;
1800         case ISCSI_PARAM_FIRST_BURST:
1801                 len = sprintf(buf, "%u\n", session->first_burst);
1802                 break;
1803         case ISCSI_PARAM_MAX_BURST:
1804                 len = sprintf(buf, "%u\n", session->max_burst);
1805                 break;
1806         case ISCSI_PARAM_PDU_INORDER_EN:
1807                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
1808                 break;
1809         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1810                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
1811                 break;
1812         case ISCSI_PARAM_ERL:
1813                 len = sprintf(buf, "%d\n", session->erl);
1814                 break;
1815         case ISCSI_PARAM_TARGET_NAME:
1816                 len = sprintf(buf, "%s\n", session->targetname);
1817                 break;
1818         case ISCSI_PARAM_TPGT:
1819                 len = sprintf(buf, "%d\n", session->tpgt);
1820                 break;
1821         default:
1822                 return -ENOSYS;
1823         }
1824
1825         return len;
1826 }
1827 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
1828
1829 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
1830                          enum iscsi_param param, char *buf)
1831 {
1832         struct iscsi_conn *conn = cls_conn->dd_data;
1833         int len;
1834
1835         switch(param) {
1836         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1837                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
1838                 break;
1839         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1840                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
1841                 break;
1842         case ISCSI_PARAM_HDRDGST_EN:
1843                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
1844                 break;
1845         case ISCSI_PARAM_DATADGST_EN:
1846                 len = sprintf(buf, "%d\n", conn->datadgst_en);
1847                 break;
1848         case ISCSI_PARAM_IFMARKER_EN:
1849                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
1850                 break;
1851         case ISCSI_PARAM_OFMARKER_EN:
1852                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
1853                 break;
1854         case ISCSI_PARAM_EXP_STATSN:
1855                 len = sprintf(buf, "%u\n", conn->exp_statsn);
1856                 break;
1857         case ISCSI_PARAM_PERSISTENT_PORT:
1858                 len = sprintf(buf, "%d\n", conn->persistent_port);
1859                 break;
1860         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1861                 len = sprintf(buf, "%s\n", conn->persistent_address);
1862                 break;
1863         default:
1864                 return -ENOSYS;
1865         }
1866
1867         return len;
1868 }
1869 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
1870
1871 MODULE_AUTHOR("Mike Christie");
1872 MODULE_DESCRIPTION("iSCSI library functions");
1873 MODULE_LICENSE("GPL");