git.oblomov.eu Git - linux-2.6/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 {
  73         struct iscsi_conn *conn = ctask->conn;
  74
  75         memset(hdr, 0, sizeof(struct iscsi_data));
  76         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
  77         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
  78         ctask->unsol_datasn++;
  79         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
  80         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
  81
  82         hdr->itt = ctask->hdr->itt;
  83         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
  84         hdr->offset = cpu_to_be32(ctask->unsol_offset);
  85
  86         if (ctask->unsol_count > conn->max_xmit_dlength) {
  87                 hton24(hdr->dlength, conn->max_xmit_dlength);
  88                 ctask->data_count = conn->max_xmit_dlength;
  89                 ctask->unsol_offset += ctask->data_count;
  90                 hdr->flags = 0;
  91         } else {
  92                 hton24(hdr->dlength, ctask->unsol_count);
  93                 ctask->data_count = ctask->unsol_count;
  94                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
  95         }
  96 }
  97 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
  98
  99 /**
 100  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
 101  * @ctask: iscsi cmd task
 102  *
 103  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
 104  * fields like dlength or final based on how much data it sends
 105  */
 106 static void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
 107 {
 108         struct iscsi_conn *conn = ctask->conn;
 109         struct iscsi_session *session = conn->session;
 110         struct iscsi_cmd *hdr = ctask->hdr;
 111         struct scsi_cmnd *sc = ctask->sc;
 112
 113         hdr->opcode = ISCSI_OP_SCSI_CMD;
 114         hdr->flags = ISCSI_ATTR_SIMPLE;
 115         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
 116         hdr->itt = ctask->itt | (conn->id << ISCSI_CID_SHIFT) |
 117                          (session->age << ISCSI_AGE_SHIFT);
 118         hdr->data_length = cpu_to_be32(sc->request_bufflen);
 119         hdr->cmdsn = cpu_to_be32(session->cmdsn);
 120         session->cmdsn++;
 121         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 122         memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
 123         memset(&hdr->cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len);
 124
 125         ctask->data_count = 0;
 126         if (sc->sc_data_direction == DMA_TO_DEVICE) {
 127                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 128                 /*
 129                  * Write counters:
 130                  *
 131                  *      imm_count       bytes to be sent right after
 132                  *                      SCSI PDU Header
 133                  *
 134                  *      unsol_count     bytes(as Data-Out) to be sent
 135                  *                      without R2T ack right after
 136                  *                      immediate data
 137                  *
 138                  *      r2t_data_count  bytes to be sent via R2T ack's
 139                  *
 140                  *      pad_count       bytes to be sent as zero-padding
 141                  */
 142                 ctask->imm_count = 0;
 143                 ctask->unsol_count = 0;
 144                 ctask->unsol_offset = 0;
 145                 ctask->unsol_datasn = 0;
 146
 147                 if (session->imm_data_en) {
 148                         if (ctask->total_length >= session->first_burst)
 149                                 ctask->imm_count = min(session->first_burst,
 150                                                         conn->max_xmit_dlength);
 151                         else
 152                                 ctask->imm_count = min(ctask->total_length,
 153                                                         conn->max_xmit_dlength);
 154                         hton24(ctask->hdr->dlength, ctask->imm_count);
 155                 } else
 156                         zero_data(ctask->hdr->dlength);
 157
 158                 if (!session->initial_r2t_en) {
 159                         ctask->unsol_count = min(session->first_burst,
 160                                 ctask->total_length) - ctask->imm_count;
 161                         ctask->unsol_offset = ctask->imm_count;
 162                 }
 163
 164                 if (!ctask->unsol_count)
 165                         /* No unsolicit Data-Out's */
 166                         ctask->hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 167         } else {
 168                 ctask->datasn = 0;
 169                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 170                 zero_data(hdr->dlength);
 171
 172                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
 173                         hdr->flags |= ISCSI_FLAG_CMD_READ;
 174         }
 175
 176         conn->scsicmd_pdus_cnt++;
 177 }
 178 EXPORT_SYMBOL_GPL(iscsi_prep_scsi_cmd_pdu);
 179
 180 /**
 181  * iscsi_complete_command - return command back to scsi-ml
 182  * @ctask: iscsi cmd task
 183  *
 184  * Must be called with session lock.
 185  * This function returns the scsi command to scsi-ml and returns
 186  * the cmd task to the pool of available cmd tasks.
 187  */
 188 static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
 189 {
 190         struct iscsi_session *session = ctask->conn->session;
 191         struct scsi_cmnd *sc = ctask->sc;
 192
 193         ctask->state = ISCSI_TASK_COMPLETED;
 194         ctask->sc = NULL;
 195         list_del_init(&ctask->running);
 196         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
 197         sc->scsi_done(sc);
 198 }
 199
 200 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
 201 {
 202         atomic_inc(&ctask->refcount);
 203 }
 204
 205 static void iscsi_get_ctask(struct iscsi_cmd_task *ctask)
 206 {
 207         spin_lock_bh(&ctask->conn->session->lock);
 208         __iscsi_get_ctask(ctask);
 209         spin_unlock_bh(&ctask->conn->session->lock);
 210 }
 211
 212 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
 213 {
 214         struct iscsi_conn *conn = ctask->conn;
 215
 216         if (atomic_dec_and_test(&ctask->refcount)) {
 217                 conn->session->tt->cleanup_cmd_task(conn, ctask);
 218                 iscsi_complete_command(ctask);
 219         }
 220 }
 221
 222 static void iscsi_put_ctask(struct iscsi_cmd_task *ctask)
 223 {
 224         spin_lock_bh(&ctask->conn->session->lock);
 225         __iscsi_put_ctask(ctask);
 226         spin_unlock_bh(&ctask->conn->session->lock);
 227 }
 228
 229 /**
 230  * iscsi_cmd_rsp - SCSI Command Response processing
 231  * @conn: iscsi connection
 232  * @hdr: iscsi header
 233  * @ctask: scsi command task
 234  * @data: cmd data buffer
 235  * @datalen: len of buffer
 236  *
 237  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 238  * then completes the command and task.
 239  **/
 240 static int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 241                               struct iscsi_cmd_task *ctask, char *data,
 242                               int datalen)
 243 {
 244         int rc;
 245         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
 246         struct iscsi_session *session = conn->session;
 247         struct scsi_cmnd *sc = ctask->sc;
 248
 249         rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
 250         if (rc) {
 251                 sc->result = DID_ERROR << 16;
 252                 goto out;
 253         }
 254
 255         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 256
 257         sc->result = (DID_OK << 16) | rhdr->cmd_status;
 258
 259         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 260                 sc->result = DID_ERROR << 16;
 261                 goto out;
 262         }
 263
 264         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 265                 int senselen;
 266
 267                 if (datalen < 2) {
 268 invalid_datalen:
 269                         printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
 270                                "invalid data buffer size of %d\n", datalen);
 271                         sc->result = DID_BAD_TARGET << 16;
 272                         goto out;
 273                 }
 274
 275                 senselen = (data[0] << 8) | data[1];
 276                 if (datalen < senselen)
 277                         goto invalid_datalen;
 278
 279                 memcpy(sc->sense_buffer, data + 2,
 280                        min(senselen, SCSI_SENSE_BUFFERSIZE));
 281                 debug_scsi("copied %d bytes of sense\n",
 282                            min(senselen, SCSI_SENSE_BUFFERSIZE));
 283         }
 284
 285         if (sc->sc_data_direction == DMA_TO_DEVICE)
 286                 goto out;
 287
 288         if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
 289                 int res_count = be32_to_cpu(rhdr->residual_count);
 290
 291                 if (res_count > 0 && res_count <= sc->request_bufflen)
 292                         sc->resid = res_count;
 293                 else
 294                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 295         } else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
 296                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 297         else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW)
 298                 sc->resid = be32_to_cpu(rhdr->residual_count);
 299
 300 out:
 301         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
 302                    (long)sc, sc->result, ctask->itt);
 303         conn->scsirsp_pdus_cnt++;
 304
 305         __iscsi_put_ctask(ctask);
 306         return rc;
 307 }
 308
 309 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 310 {
 311         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 312
 313         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 314         conn->tmfrsp_pdus_cnt++;
 315
 316         if (conn->tmabort_state != TMABORT_INITIAL)
 317                 return;
 318
 319         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 320                 conn->tmabort_state = TMABORT_SUCCESS;
 321         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 322                 conn->tmabort_state = TMABORT_NOT_FOUND;
 323         else
 324                 conn->tmabort_state = TMABORT_FAILED;
 325         wake_up(&conn->ehwait);
 326 }
 327
 328 /**
 329  * __iscsi_complete_pdu - complete pdu
 330  * @conn: iscsi conn
 331  * @hdr: iscsi header
 332  * @data: data buffer
 333  * @datalen: len of data buffer
 334  *
 335  * Completes pdu processing by freeing any resources allocated at
 336  * queuecommand or send generic. session lock must be held and verify
 337  * itt must have been called.
 338  */
 339 int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 340                          char *data, int datalen)
 341 {
 342         struct iscsi_session *session = conn->session;
 343         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
 344         struct iscsi_cmd_task *ctask;
 345         struct iscsi_mgmt_task *mtask;
 346         uint32_t itt;
 347
 348         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG))
 349                 itt = hdr->itt & ISCSI_ITT_MASK;
 350         else
 351                 itt = hdr->itt;
 352
 353         if (itt < session->cmds_max) {
 354                 ctask = session->cmds[itt];
 355
 356                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 357                            opcode, conn->id, ctask->itt, datalen);
 358
 359                 switch(opcode) {
 360                 case ISCSI_OP_SCSI_CMD_RSP:
 361                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 362                         rc = iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
 363                                                 datalen);
 364                         break;
 365                 case ISCSI_OP_SCSI_DATA_IN:
 366                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 367                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
 368                                 conn->scsirsp_pdus_cnt++;
 369                                 __iscsi_put_ctask(ctask);
 370                         }
 371                         break;
 372                 case ISCSI_OP_R2T:
 373                         /* LLD handles this for now */
 374                         break;
 375                 default:
 376                         rc = ISCSI_ERR_BAD_OPCODE;
 377                         break;
 378                 }
 379         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
 380                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
 381                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
 382
 383                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 384                            opcode, conn->id, mtask->itt, datalen);
 385
 386                 rc = iscsi_check_assign_cmdsn(session,
 387                                               (struct iscsi_nopin*)hdr);
 388                 if (rc)
 389                         goto done;
 390
 391                 switch(opcode) {
 392                 case ISCSI_OP_LOGOUT_RSP:
 393                         if (datalen) {
 394                                 rc = ISCSI_ERR_PROTO;
 395                                 break;
 396                         }
 397                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 398                         /* fall through */
 399                 case ISCSI_OP_LOGIN_RSP:
 400                 case ISCSI_OP_TEXT_RSP:
 401                         /*
 402                          * login related PDU's exp_statsn is handled in
 403                          * userspace
 404                          */
 405                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 406                                 rc = ISCSI_ERR_CONN_FAILED;
 407                         list_del(&mtask->running);
 408                         if (conn->login_mtask != mtask)
 409                                 __kfifo_put(session->mgmtpool.queue,
 410                                             (void*)&mtask, sizeof(void*));
 411                         break;
 412                 case ISCSI_OP_SCSI_TMFUNC_RSP:
 413                         if (datalen) {
 414                                 rc = ISCSI_ERR_PROTO;
 415                                 break;
 416                         }
 417
 418                         iscsi_tmf_rsp(conn, hdr);
 419                         break;
 420                 case ISCSI_OP_NOOP_IN:
 421                         if (hdr->ttt != ISCSI_RESERVED_TAG || datalen) {
 422                                 rc = ISCSI_ERR_PROTO;
 423                                 break;
 424                         }
 425                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 426
 427                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 428                                 rc = ISCSI_ERR_CONN_FAILED;
 429                         list_del(&mtask->running);
 430                         if (conn->login_mtask != mtask)
 431                                 __kfifo_put(session->mgmtpool.queue,
 432                                             (void*)&mtask, sizeof(void*));
 433                         break;
 434                 default:
 435                         rc = ISCSI_ERR_BAD_OPCODE;
 436                         break;
 437                 }
 438         } else if (itt == ISCSI_RESERVED_TAG) {
 439                 switch(opcode) {
 440                 case ISCSI_OP_NOOP_IN:
 441                         if (datalen) {
 442                                 rc = ISCSI_ERR_PROTO;
 443                                 break;
 444                         }
 445
 446                         rc = iscsi_check_assign_cmdsn(session,
 447                                                  (struct iscsi_nopin*)hdr);
 448                         if (rc)
 449                                 break;
 450
 451                         if (hdr->ttt == ISCSI_RESERVED_TAG)
 452                                 break;
 453
 454                         if (iscsi_recv_pdu(conn->cls_conn, hdr, NULL, 0))
 455                                 rc = ISCSI_ERR_CONN_FAILED;
 456                         break;
 457                 case ISCSI_OP_REJECT:
 458                         /* we need sth like iscsi_reject_rsp()*/
 459                 case ISCSI_OP_ASYNC_EVENT:
 460                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 461                         /* we need sth like iscsi_async_event_rsp() */
 462                         rc = ISCSI_ERR_BAD_OPCODE;
 463                         break;
 464                 default:
 465                         rc = ISCSI_ERR_BAD_OPCODE;
 466                         break;
 467                 }
 468         } else
 469                 rc = ISCSI_ERR_BAD_ITT;
 470
 471 done:
 472         return rc;
 473 }
 474 EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
 475
 476 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 477                        char *data, int datalen)
 478 {
 479         int rc;
 480
 481         spin_lock(&conn->session->lock);
 482         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
 483         spin_unlock(&conn->session->lock);
 484         return rc;
 485 }
 486 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 487
 488 /* verify itt (itt encoding: age+cid+itt) */
 489 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 490                      uint32_t *ret_itt)
 491 {
 492         struct iscsi_session *session = conn->session;
 493         struct iscsi_cmd_task *ctask;
 494         uint32_t itt;
 495
 496         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
 497                 if ((hdr->itt & ISCSI_AGE_MASK) !=
 498                     (session->age << ISCSI_AGE_SHIFT)) {
 499                         printk(KERN_ERR "iscsi: received itt %x expected "
 500                                 "session age (%x)\n", hdr->itt,
 501                                 session->age & ISCSI_AGE_MASK);
 502                         return ISCSI_ERR_BAD_ITT;
 503                 }
 504
 505                 if ((hdr->itt & ISCSI_CID_MASK) !=
 506                     (conn->id << ISCSI_CID_SHIFT)) {
 507                         printk(KERN_ERR "iscsi: received itt %x, expected "
 508                                 "CID (%x)\n", hdr->itt, conn->id);
 509                         return ISCSI_ERR_BAD_ITT;
 510                 }
 511                 itt = hdr->itt & ISCSI_ITT_MASK;
 512         } else
 513                 itt = hdr->itt;
 514
 515         if (itt < session->cmds_max) {
 516                 ctask = session->cmds[itt];
 517
 518                 if (!ctask->sc) {
 519                         printk(KERN_INFO "iscsi: dropping ctask with "
 520                                "itt 0x%x\n", ctask->itt);
 521                         /* force drop */
 522                         return ISCSI_ERR_NO_SCSI_CMD;
 523                 }
 524
 525                 if (ctask->sc->SCp.phase != session->age) {
 526                         printk(KERN_ERR "iscsi: ctask's session age %d, "
 527                                 "expected %d\n", ctask->sc->SCp.phase,
 528                                 session->age);
 529                         return ISCSI_ERR_SESSION_FAILED;
 530                 }
 531         }
 532
 533         *ret_itt = itt;
 534         return 0;
 535 }
 536 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 537
 538 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 539 {
 540         struct iscsi_session *session = conn->session;
 541         unsigned long flags;
 542
 543         spin_lock_irqsave(&session->lock, flags);
 544         if (session->state == ISCSI_STATE_FAILED) {
 545                 spin_unlock_irqrestore(&session->lock, flags);
 546                 return;
 547         }
 548
 549         if (conn->stop_stage == 0)
 550                 session->state = ISCSI_STATE_FAILED;
 551         spin_unlock_irqrestore(&session->lock, flags);
 552         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 553         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 554         iscsi_conn_error(conn->cls_conn, err);
 555 }
 556 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 557
 558 /**
 559  * iscsi_data_xmit - xmit any command into the scheduled connection
 560  * @conn: iscsi connection
 561  *
 562  * Notes:
 563  *      The function can return -EAGAIN in which case the caller must
 564  *      re-schedule it again later or recover. '0' return code means
 565  *      successful xmit.
 566  **/
 567 static int iscsi_data_xmit(struct iscsi_conn *conn)
 568 {
 569         struct iscsi_transport *tt;
 570         int rc = 0;
 571
 572         if (unlikely(conn->suspend_tx)) {
 573                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 574                 return -ENODATA;
 575         }
 576         tt = conn->session->tt;
 577
 578         /*
 579          * Transmit in the following order:
 580          *
 581          * 1) un-finished xmit (ctask or mtask)
 582          * 2) immediate control PDUs
 583          * 3) write data
 584          * 4) SCSI commands
 585          * 5) non-immediate control PDUs
 586          *
 587          * No need to lock around __kfifo_get as long as
 588          * there's one producer and one consumer.
 589          */
 590
 591         BUG_ON(conn->ctask && conn->mtask);
 592
 593         if (conn->ctask) {
 594                 iscsi_get_ctask(conn->ctask);
 595                 rc = tt->xmit_cmd_task(conn, conn->ctask);
 596                 iscsi_put_ctask(conn->ctask);
 597                 if (rc)
 598                         goto again;
 599                 /* done with this in-progress ctask */
 600                 conn->ctask = NULL;
 601         }
 602         if (conn->mtask) {
 603                 rc = tt->xmit_mgmt_task(conn, conn->mtask);
 604                 if (rc)
 605                         goto again;
 606                 /* done with this in-progress mtask */
 607                 conn->mtask = NULL;
 608         }
 609
 610         /* process immediate first */
 611         if (unlikely(__kfifo_len(conn->immqueue))) {
 612                 while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
 613                                    sizeof(void*))) {
 614                         spin_lock_bh(&conn->session->lock);
 615                         list_add_tail(&conn->mtask->running,
 616                                       &conn->mgmt_run_list);
 617                         spin_unlock_bh(&conn->session->lock);
 618                         rc = tt->xmit_mgmt_task(conn, conn->mtask);
 619                         if (rc)
 620                                 goto again;
 621                 }
 622                 /* done with this mtask */
 623                 conn->mtask = NULL;
 624         }
 625
 626         /* process command queue */
 627         spin_lock_bh(&conn->session->lock);
 628         while (!list_empty(&conn->xmitqueue)) {
 629                 /*
 630                  * iscsi tcp may readd the task to the xmitqueue to send
 631                  * write data
 632                  */
 633                 conn->ctask = list_entry(conn->xmitqueue.next,
 634                                          struct iscsi_cmd_task, running);
 635                 conn->ctask->state = ISCSI_TASK_RUNNING;
 636                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
 637                 __iscsi_get_ctask(conn->ctask);
 638                 spin_unlock_bh(&conn->session->lock);
 639
 640                 rc = tt->xmit_cmd_task(conn, conn->ctask);
 641                 if (rc)
 642                         goto again;
 643
 644                 spin_lock_bh(&conn->session->lock);
 645                 __iscsi_put_ctask(conn->ctask);
 646                 if (rc) {
 647                         spin_unlock_bh(&conn->session->lock);
 648                         goto again;
 649                 }
 650         }
 651         spin_unlock_bh(&conn->session->lock);
 652         /* done with this ctask */
 653         conn->ctask = NULL;
 654
 655         /* process the rest control plane PDUs, if any */
 656         if (unlikely(__kfifo_len(conn->mgmtqueue))) {
 657                 while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
 658                                    sizeof(void*))) {
 659                         spin_lock_bh(&conn->session->lock);
 660                         list_add_tail(&conn->mtask->running,
 661                                       &conn->mgmt_run_list);
 662                         spin_unlock_bh(&conn->session->lock);
 663                         rc = tt->xmit_mgmt_task(conn, conn->mtask);
 664                         if (rc)
 665                                 goto again;
 666                 }
 667                 /* done with this mtask */
 668                 conn->mtask = NULL;
 669         }
 670
 671         return -ENODATA;
 672
 673 again:
 674         if (unlikely(conn->suspend_tx))
 675                 return -ENODATA;
 676
 677         return rc;
 678 }
 679
 680 static void iscsi_xmitworker(void *data)
 681 {
 682         struct iscsi_conn *conn = data;
 683         int rc;
 684         /*
 685          * serialize Xmit worker on a per-connection basis.
 686          */
 687         mutex_lock(&conn->xmitmutex);
 688         do {
 689                 rc = iscsi_data_xmit(conn);
 690         } while (rc >= 0 || rc == -EAGAIN);
 691         mutex_unlock(&conn->xmitmutex);
 692 }
 693
 694 enum {
 695         FAILURE_BAD_HOST = 1,
 696         FAILURE_SESSION_FAILED,
 697         FAILURE_SESSION_FREED,
 698         FAILURE_WINDOW_CLOSED,
 699         FAILURE_OOM,
 700         FAILURE_SESSION_TERMINATE,
 701         FAILURE_SESSION_IN_RECOVERY,
 702         FAILURE_SESSION_RECOVERY_TIMEOUT,
 703 };
 704
 705 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 706 {
 707         struct Scsi_Host *host;
 708         int reason = 0;
 709         struct iscsi_session *session;
 710         struct iscsi_conn *conn;
 711         struct iscsi_cmd_task *ctask = NULL;
 712
 713         sc->scsi_done = done;
 714         sc->result = 0;
 715
 716         host = sc->device->host;
 717         session = iscsi_hostdata(host->hostdata);
 718
 719         spin_lock(&session->lock);
 720
 721         /*
 722          * ISCSI_STATE_FAILED is a temp. state. The recovery
 723          * code will decide what is best to do with command queued
 724          * during this time
 725          */
 726         if (session->state != ISCSI_STATE_LOGGED_IN &&
 727             session->state != ISCSI_STATE_FAILED) {
 728                 /*
 729                  * to handle the race between when we set the recovery state
 730                  * and block the session we requeue here (commands could
 731                  * be entering our queuecommand while a block is starting
 732                  * up because the block code is not locked)
 733                  */
 734                 if (session->state == ISCSI_STATE_IN_RECOVERY) {
 735                         reason = FAILURE_SESSION_IN_RECOVERY;
 736                         goto reject;
 737                 }
 738
 739                 if (session->state == ISCSI_STATE_RECOVERY_FAILED)
 740                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
 741                 else if (session->state == ISCSI_STATE_TERMINATE)
 742                         reason = FAILURE_SESSION_TERMINATE;
 743                 else
 744                         reason = FAILURE_SESSION_FREED;
 745                 goto fault;
 746         }
 747
 748         /*
 749          * Check for iSCSI window and take care of CmdSN wrap-around
 750          */
 751         if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
 752                 reason = FAILURE_WINDOW_CLOSED;
 753                 goto reject;
 754         }
 755
 756         conn = session->leadconn;
 757
 758         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
 759                          sizeof(void*))) {
 760                 reason = FAILURE_OOM;
 761                 goto reject;
 762         }
 763         sc->SCp.phase = session->age;
 764         sc->SCp.ptr = (char *)ctask;
 765
 766         atomic_set(&ctask->refcount, 1);
 767         ctask->state = ISCSI_TASK_PENDING;
 768         ctask->mtask = NULL;
 769         ctask->conn = conn;
 770         ctask->sc = sc;
 771         INIT_LIST_HEAD(&ctask->running);
 772         ctask->total_length = sc->request_bufflen;
 773         iscsi_prep_scsi_cmd_pdu(ctask);
 774
 775         session->tt->init_cmd_task(ctask);
 776
 777         list_add_tail(&ctask->running, &conn->xmitqueue);
 778         debug_scsi(
 779                "ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n",
 780                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
 781                 conn->id, (long)sc, ctask->itt, sc->request_bufflen,
 782                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 783         spin_unlock(&session->lock);
 784
 785         scsi_queue_work(host, &conn->xmitwork);
 786         return 0;
 787
 788 reject:
 789         spin_unlock(&session->lock);
 790         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
 791         return SCSI_MLQUEUE_HOST_BUSY;
 792
 793 fault:
 794         spin_unlock(&session->lock);
 795         printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
 796                sc->cmnd[0], reason);
 797         sc->result = (DID_NO_CONNECT << 16);
 798         sc->resid = sc->request_bufflen;
 799         sc->scsi_done(sc);
 800         return 0;
 801 }
 802 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
 803
 804 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
 805 {
 806         if (depth > ISCSI_MAX_CMD_PER_LUN)
 807                 depth = ISCSI_MAX_CMD_PER_LUN;
 808         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 809         return sdev->queue_depth;
 810 }
 811 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
 812
 813 static int
 814 iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 815                         char *data, uint32_t data_size)
 816 {
 817         struct iscsi_session *session = conn->session;
 818         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 819         struct iscsi_mgmt_task *mtask;
 820
 821         spin_lock_bh(&session->lock);
 822         if (session->state == ISCSI_STATE_TERMINATE) {
 823                 spin_unlock_bh(&session->lock);
 824                 return -EPERM;
 825         }
 826         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
 827             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 828                 /*
 829                  * Login and Text are sent serially, in
 830                  * request-followed-by-response sequence.
 831                  * Same mtask can be used. Same ITT must be used.
 832                  * Note that login_mtask is preallocated at conn_create().
 833                  */
 834                 mtask = conn->login_mtask;
 835         else {
 836                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 837                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 838
 839                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 840                 if (!__kfifo_get(session->mgmtpool.queue,
 841                                  (void*)&mtask, sizeof(void*))) {
 842                         spin_unlock_bh(&session->lock);
 843                         return -ENOSPC;
 844                 }
 845         }
 846
 847         /*
 848          * pre-format CmdSN for outgoing PDU.
 849          */
 850         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
 851                 hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) |
 852                            (session->age << ISCSI_AGE_SHIFT);
 853                 nop->cmdsn = cpu_to_be32(session->cmdsn);
 854                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 855                     !(hdr->opcode & ISCSI_OP_IMMEDIATE))
 856                         session->cmdsn++;
 857         } else
 858                 /* do not advance CmdSN */
 859                 nop->cmdsn = cpu_to_be32(session->cmdsn);
 860
 861         if (data_size) {
 862                 memcpy(mtask->data, data, data_size);
 863                 mtask->data_count = data_size;
 864         } else
 865                 mtask->data_count = 0;
 866
 867         INIT_LIST_HEAD(&mtask->running);
 868         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
 869         if (session->tt->init_mgmt_task)
 870                 session->tt->init_mgmt_task(conn, mtask, data, data_size);
 871         spin_unlock_bh(&session->lock);
 872
 873         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 874                    hdr->opcode, hdr->itt, data_size);
 875
 876         /*
 877          * since send_pdu() could be called at least from two contexts,
 878          * we need to serialize __kfifo_put, so we don't have to take
 879          * additional lock on fast data-path
 880          */
 881         if (hdr->opcode & ISCSI_OP_IMMEDIATE)
 882                 __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
 883         else
 884                 __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
 885
 886         scsi_queue_work(session->host, &conn->xmitwork);
 887         return 0;
 888 }
 889
 890 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 891                         char *data, uint32_t data_size)
 892 {
 893         struct iscsi_conn *conn = cls_conn->dd_data;
 894         int rc;
 895
 896         mutex_lock(&conn->xmitmutex);
 897         rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
 898         mutex_unlock(&conn->xmitmutex);
 899
 900         return rc;
 901 }
 902 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 903
 904 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
 905 {
 906         struct iscsi_session *session = class_to_transport_session(cls_session);
 907         struct iscsi_conn *conn = session->leadconn;
 908
 909         spin_lock_bh(&session->lock);
 910         if (session->state != ISCSI_STATE_LOGGED_IN) {
 911                 session->state = ISCSI_STATE_RECOVERY_FAILED;
 912                 if (conn)
 913                         wake_up(&conn->ehwait);
 914         }
 915         spin_unlock_bh(&session->lock);
 916 }
 917 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
 918
 919 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
 920 {
 921         struct Scsi_Host *host = sc->device->host;
 922         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
 923         struct iscsi_conn *conn = session->leadconn;
 924         int fail_session = 0;
 925
 926         spin_lock_bh(&session->lock);
 927         if (session->state == ISCSI_STATE_TERMINATE) {
 928 failed:
 929                 debug_scsi("failing host reset: session terminated "
 930                            "[CID %d age %d]", conn->id, session->age);
 931                 spin_unlock_bh(&session->lock);
 932                 return FAILED;
 933         }
 934
 935         if (sc->SCp.phase == session->age) {
 936                 debug_scsi("failing connection CID %d due to SCSI host reset",
 937                            conn->id);
 938                 fail_session = 1;
 939         }
 940         spin_unlock_bh(&session->lock);
 941
 942         /*
 943          * we drop the lock here but the leadconn cannot be destoyed while
 944          * we are in the scsi eh
 945          */
 946         if (fail_session)
 947                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 948
 949         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
 950         wait_event_interruptible(conn->ehwait,
 951                                  session->state == ISCSI_STATE_TERMINATE ||
 952                                  session->state == ISCSI_STATE_LOGGED_IN ||
 953                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
 954         if (signal_pending(current))
 955                 flush_signals(current);
 956
 957         spin_lock_bh(&session->lock);
 958         if (session->state == ISCSI_STATE_LOGGED_IN)
 959                 printk(KERN_INFO "iscsi: host reset succeeded\n");
 960         else
 961                 goto failed;
 962         spin_unlock_bh(&session->lock);
 963
 964         return SUCCESS;
 965 }
 966 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
 967
 968 static void iscsi_tmabort_timedout(unsigned long data)
 969 {
 970         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
 971         struct iscsi_conn *conn = ctask->conn;
 972         struct iscsi_session *session = conn->session;
 973
 974         spin_lock(&session->lock);
 975         if (conn->tmabort_state == TMABORT_INITIAL) {
 976                 conn->tmabort_state = TMABORT_TIMEDOUT;
 977                 debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
 978                         ctask->sc, ctask->itt);
 979                 /* unblock eh_abort() */
 980                 wake_up(&conn->ehwait);
 981         }
 982         spin_unlock(&session->lock);
 983 }
 984
 985 /* must be called with the mutex lock */
 986 static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
 987                                  struct iscsi_cmd_task *ctask)
 988 {
 989         struct iscsi_conn *conn = ctask->conn;
 990         struct iscsi_session *session = conn->session;
 991         struct iscsi_tm *hdr = &conn->tmhdr;
 992         int rc;
 993
 994         /*
 995          * ctask timed out but session is OK requests must be serialized.
 996          */
 997         memset(hdr, 0, sizeof(struct iscsi_tm));
 998         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
 999         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
1000         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1001         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1002         hdr->rtt = ctask->hdr->itt;
1003         hdr->refcmdsn = ctask->hdr->cmdsn;
1004
1005         rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
1006                                      NULL, 0);
1007         if (rc) {
1008                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1009                 debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc);
1010                 return rc;
1011         }
1012
1013         debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
1014
1015         spin_lock_bh(&session->lock);
1016         ctask->mtask = (struct iscsi_mgmt_task *)
1017                         session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) -
1018                                         ISCSI_MGMT_ITT_OFFSET];
1019
1020         if (conn->tmabort_state == TMABORT_INITIAL) {
1021                 conn->tmfcmd_pdus_cnt++;
1022                 conn->tmabort_timer.expires = 10*HZ + jiffies;
1023                 conn->tmabort_timer.function = iscsi_tmabort_timedout;
1024                 conn->tmabort_timer.data = (unsigned long)ctask;
1025                 add_timer(&conn->tmabort_timer);
1026                 debug_scsi("abort set timeout [itt 0x%x]", ctask->itt);
1027         }
1028         spin_unlock_bh(&session->lock);
1029         mutex_unlock(&conn->xmitmutex);
1030
1031         /*
1032          * block eh thread until:
1033          *
1034          * 1) abort response
1035          * 2) abort timeout
1036          * 3) session is terminated or restarted or userspace has
1037          * given up on recovery
1038          */
1039         wait_event_interruptible(conn->ehwait,
1040                                  sc->SCp.phase != session->age ||
1041                                  session->state != ISCSI_STATE_LOGGED_IN ||
1042                                  conn->tmabort_state != TMABORT_INITIAL);
1043         if (signal_pending(current))
1044                 flush_signals(current);
1045         del_timer_sync(&conn->tmabort_timer);
1046
1047         mutex_lock(&conn->xmitmutex);
1048         return 0;
1049 }
1050
1051 /*
1052  * xmit mutex and session lock must be held
1053  */
1054 static struct iscsi_mgmt_task *
1055 iscsi_remove_mgmt_task(struct kfifo *fifo, uint32_t itt)
1056 {
1057         int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);
1058         struct iscsi_mgmt_task *task;
1059
1060         debug_scsi("searching %d tasks\n", nr_tasks);
1061
1062         for (i = 0; i < nr_tasks; i++) {
1063                 __kfifo_get(fifo, (void*)&task, sizeof(void*));
1064                 debug_scsi("check task %u\n", task->itt);
1065
1066                 if (task->itt == itt) {
1067                         debug_scsi("matched task\n");
1068                         return task;
1069                 }
1070
1071                 __kfifo_put(fifo, (void*)&task, sizeof(void*));
1072         }
1073         return NULL;
1074 }
1075
1076 static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
1077 {
1078         struct iscsi_conn *conn = ctask->conn;
1079         struct iscsi_session *session = conn->session;
1080
1081         if (!ctask->mtask)
1082                 return -EINVAL;
1083
1084         if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
1085                 list_del(&ctask->mtask->running);
1086         __kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
1087                     sizeof(void*));
1088         ctask->mtask = NULL;
1089         return 0;
1090 }
1091
1092 /*
1093  * session lock and xmitmutex must be held
1094  */
1095 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1096                          int err)
1097 {
1098         struct scsi_cmnd *sc;
1099
1100         sc = ctask->sc;
1101         if (!sc)
1102                 return;
1103         iscsi_ctask_mtask_cleanup(ctask);
1104
1105         sc->result = err;
1106         sc->resid = sc->request_bufflen;
1107         __iscsi_put_ctask(ctask);
1108 }
1109
1110 int iscsi_eh_abort(struct scsi_cmnd *sc)
1111 {
1112         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1113         struct iscsi_conn *conn = ctask->conn;
1114         struct iscsi_session *session = conn->session;
1115         int rc;
1116
1117         conn->eh_abort_cnt++;
1118         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1119
1120         mutex_lock(&conn->xmitmutex);
1121         spin_lock_bh(&session->lock);
1122
1123         /*
1124          * If we are not logged in or we have started a new session
1125          * then let the host reset code handle this
1126          */
1127         if (session->state != ISCSI_STATE_LOGGED_IN ||
1128             sc->SCp.phase != session->age)
1129                 goto failed;
1130
1131         /* ctask completed before time out */
1132         if (!ctask->sc) {
1133                 spin_unlock_bh(&session->lock);
1134                 debug_scsi("sc completed while abort in progress\n");
1135                 goto success_rel_mutex;
1136         }
1137
1138         /* what should we do here ? */
1139         if (conn->ctask == ctask) {
1140                 printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. "
1141                        "Failing abort\n", sc, ctask->itt);
1142                 goto failed;
1143         }
1144
1145         if (ctask->state == ISCSI_TASK_PENDING)
1146                 goto success_cleanup;
1147
1148         conn->tmabort_state = TMABORT_INITIAL;
1149
1150         spin_unlock_bh(&session->lock);
1151         rc = iscsi_exec_abort_task(sc, ctask);
1152         spin_lock_bh(&session->lock);
1153
1154         if (rc || sc->SCp.phase != session->age ||
1155             session->state != ISCSI_STATE_LOGGED_IN)
1156                 goto failed;
1157         iscsi_ctask_mtask_cleanup(ctask);
1158
1159         switch (conn->tmabort_state) {
1160         case TMABORT_SUCCESS:
1161                 goto success_cleanup;
1162         case TMABORT_NOT_FOUND:
1163                 if (!ctask->sc) {
1164                         /* ctask completed before tmf abort response */
1165                         spin_unlock_bh(&session->lock);
1166                         debug_scsi("sc completed while abort in progress\n");
1167                         goto success_rel_mutex;
1168                 }
1169                 /* fall through */
1170         default:
1171                 /* timedout or failed */
1172                 spin_unlock_bh(&session->lock);
1173                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1174                 spin_lock_bh(&session->lock);
1175                 goto failed;
1176         }
1177
1178 success_cleanup:
1179         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1180         spin_unlock_bh(&session->lock);
1181
1182         /*
1183          * clean up task if aborted. we have the xmitmutex so grab
1184          * the recv lock as a writer
1185          */
1186         write_lock_bh(conn->recv_lock);
1187         spin_lock(&session->lock);
1188         fail_command(conn, ctask, DID_ABORT << 16);
1189         spin_unlock(&session->lock);
1190         write_unlock_bh(conn->recv_lock);
1191
1192 success_rel_mutex:
1193         mutex_unlock(&conn->xmitmutex);
1194         return SUCCESS;
1195
1196 failed:
1197         spin_unlock_bh(&session->lock);
1198         mutex_unlock(&conn->xmitmutex);
1199
1200         debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1201         return FAILED;
1202 }
1203 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1204
1205 int
1206 iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
1207 {
1208         int i;
1209
1210         *items = kmalloc(max * sizeof(void*), GFP_KERNEL);
1211         if (*items == NULL)
1212                 return -ENOMEM;
1213
1214         q->max = max;
1215         q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
1216         if (q->pool == NULL) {
1217                 kfree(*items);
1218                 return -ENOMEM;
1219         }
1220
1221         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1222                               GFP_KERNEL, NULL);
1223         if (q->queue == ERR_PTR(-ENOMEM)) {
1224                 kfree(q->pool);
1225                 kfree(*items);
1226                 return -ENOMEM;
1227         }
1228
1229         for (i = 0; i < max; i++) {
1230                 q->pool[i] = kmalloc(item_size, GFP_KERNEL);
1231                 if (q->pool[i] == NULL) {
1232                         int j;
1233
1234                         for (j = 0; j < i; j++)
1235                                 kfree(q->pool[j]);
1236
1237                         kfifo_free(q->queue);
1238                         kfree(q->pool);
1239                         kfree(*items);
1240                         return -ENOMEM;
1241                 }
1242                 memset(q->pool[i], 0, item_size);
1243                 (*items)[i] = q->pool[i];
1244                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1245         }
1246         return 0;
1247 }
1248 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1249
1250 void iscsi_pool_free(struct iscsi_queue *q, void **items)
1251 {
1252         int i;
1253
1254         for (i = 0; i < q->max; i++)
1255                 kfree(items[i]);
1256         kfree(q->pool);
1257         kfree(items);
1258 }
1259 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1260
1261 /*
1262  * iSCSI Session's hostdata organization:
1263  *
1264  *    *------------------* <== hostdata_session(host->hostdata)
1265  *    | ptr to class sess|
1266  *    |------------------| <== iscsi_hostdata(host->hostdata)
1267  *    | iscsi_session    |
1268  *    *------------------*
1269  */
1270
1271 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1272                                  _sz % sizeof(unsigned long))
1273
1274 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1275
1276 /**
1277  * iscsi_session_setup - create iscsi cls session and host and session
1278  * @scsit: scsi transport template
1279  * @iscsit: iscsi transport template
1280  * @initial_cmdsn: initial CmdSN
1281  * @hostno: host no allocated
1282  *
1283  * This can be used by software iscsi_transports that allocate
1284  * a session per scsi host.
1285  **/
1286 struct iscsi_cls_session *
1287 iscsi_session_setup(struct iscsi_transport *iscsit,
1288                     struct scsi_transport_template *scsit,
1289                     int cmd_task_size, int mgmt_task_size,
1290                     uint32_t initial_cmdsn, uint32_t *hostno)
1291 {
1292         struct Scsi_Host *shost;
1293         struct iscsi_session *session;
1294         struct iscsi_cls_session *cls_session;
1295         int cmd_i;
1296
1297         shost = scsi_host_alloc(iscsit->host_template,
1298                                 hostdata_privsize(sizeof(*session)));
1299         if (!shost)
1300                 return NULL;
1301
1302         shost->max_id = 1;
1303         shost->max_channel = 0;
1304         shost->max_lun = iscsit->max_lun;
1305         shost->max_cmd_len = iscsit->max_cmd_len;
1306         shost->transportt = scsit;
1307         shost->transportt->create_work_queue = 1;
1308         *hostno = shost->host_no;
1309
1310         session = iscsi_hostdata(shost->hostdata);
1311         memset(session, 0, sizeof(struct iscsi_session));
1312         session->host = shost;
1313         session->state = ISCSI_STATE_FREE;
1314         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1315         session->cmds_max = ISCSI_XMIT_CMDS_MAX;
1316         session->cmdsn = initial_cmdsn;
1317         session->exp_cmdsn = initial_cmdsn + 1;
1318         session->max_cmdsn = initial_cmdsn + 1;
1319         session->max_r2t = 1;
1320         session->tt = iscsit;
1321
1322         /* initialize SCSI PDU commands pool */
1323         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1324                             (void***)&session->cmds,
1325                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1326                 goto cmdpool_alloc_fail;
1327
1328         /* pre-format cmds pool with ITT */
1329         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1330                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1331
1332                 if (cmd_task_size)
1333                         ctask->dd_data = &ctask[1];
1334                 ctask->itt = cmd_i;
1335                 INIT_LIST_HEAD(&ctask->running);
1336         }
1337
1338         spin_lock_init(&session->lock);
1339         INIT_LIST_HEAD(&session->connections);
1340
1341         /* initialize immediate command pool */
1342         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1343                            (void***)&session->mgmt_cmds,
1344                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1345                 goto mgmtpool_alloc_fail;
1346
1347
1348         /* pre-format immediate cmds pool with ITT */
1349         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1350                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1351
1352                 if (mgmt_task_size)
1353                         mtask->dd_data = &mtask[1];
1354                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1355                 INIT_LIST_HEAD(&mtask->running);
1356         }
1357
1358         if (scsi_add_host(shost, NULL))
1359                 goto add_host_fail;
1360
1361         if (!try_module_get(iscsit->owner))
1362                 goto cls_session_fail;
1363
1364         cls_session = iscsi_create_session(shost, iscsit, 0);
1365         if (!cls_session)
1366                 goto module_put;
1367         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1368
1369         return cls_session;
1370
1371 module_put:
1372         module_put(iscsit->owner);
1373 cls_session_fail:
1374         scsi_remove_host(shost);
1375 add_host_fail:
1376         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1377 mgmtpool_alloc_fail:
1378         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1379 cmdpool_alloc_fail:
1380         scsi_host_put(shost);
1381         return NULL;
1382 }
1383 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1384
1385 /**
1386  * iscsi_session_teardown - destroy session, host, and cls_session
1387  * shost: scsi host
1388  *
1389  * This can be used by software iscsi_transports that allocate
1390  * a session per scsi host.
1391  **/
1392 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1393 {
1394         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1395         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1396         struct module *owner = cls_session->transport->owner;
1397
1398         scsi_remove_host(shost);
1399
1400         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1401         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1402
1403         kfree(session->targetname);
1404
1405         iscsi_destroy_session(cls_session);
1406         scsi_host_put(shost);
1407         module_put(owner);
1408 }
1409 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1410
1411 /**
1412  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1413  * @cls_session: iscsi_cls_session
1414  * @conn_idx: cid
1415  **/
1416 struct iscsi_cls_conn *
1417 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1418 {
1419         struct iscsi_session *session = class_to_transport_session(cls_session);
1420         struct iscsi_conn *conn;
1421         struct iscsi_cls_conn *cls_conn;
1422         char *data;
1423
1424         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1425         if (!cls_conn)
1426                 return NULL;
1427         conn = cls_conn->dd_data;
1428         memset(conn, 0, sizeof(*conn));
1429
1430         conn->session = session;
1431         conn->cls_conn = cls_conn;
1432         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1433         conn->id = conn_idx;
1434         conn->exp_statsn = 0;
1435         conn->tmabort_state = TMABORT_INITIAL;
1436         INIT_LIST_HEAD(&conn->run_list);
1437         INIT_LIST_HEAD(&conn->mgmt_run_list);
1438         INIT_LIST_HEAD(&conn->xmitqueue);
1439
1440         /* initialize general immediate & non-immediate PDU commands queue */
1441         conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1442                                         GFP_KERNEL, NULL);
1443         if (conn->immqueue == ERR_PTR(-ENOMEM))
1444                 goto immqueue_alloc_fail;
1445
1446         conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1447                                         GFP_KERNEL, NULL);
1448         if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
1449                 goto mgmtqueue_alloc_fail;
1450
1451         INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
1452
1453         /* allocate login_mtask used for the login/text sequences */
1454         spin_lock_bh(&session->lock);
1455         if (!__kfifo_get(session->mgmtpool.queue,
1456                          (void*)&conn->login_mtask,
1457                          sizeof(void*))) {
1458                 spin_unlock_bh(&session->lock);
1459                 goto login_mtask_alloc_fail;
1460         }
1461         spin_unlock_bh(&session->lock);
1462
1463         data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
1464         if (!data)
1465                 goto login_mtask_data_alloc_fail;
1466         conn->login_mtask->data = conn->data = data;
1467
1468         init_timer(&conn->tmabort_timer);
1469         mutex_init(&conn->xmitmutex);
1470         init_waitqueue_head(&conn->ehwait);
1471
1472         return cls_conn;
1473
1474 login_mtask_data_alloc_fail:
1475         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1476                     sizeof(void*));
1477 login_mtask_alloc_fail:
1478         kfifo_free(conn->mgmtqueue);
1479 mgmtqueue_alloc_fail:
1480         kfifo_free(conn->immqueue);
1481 immqueue_alloc_fail:
1482         iscsi_destroy_conn(cls_conn);
1483         return NULL;
1484 }
1485 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1486
1487 /**
1488  * iscsi_conn_teardown - teardown iscsi connection
1489  * cls_conn: iscsi class connection
1490  *
1491  * TODO: we may need to make this into a two step process
1492  * like scsi-mls remove + put host
1493  */
1494 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1495 {
1496         struct iscsi_conn *conn = cls_conn->dd_data;
1497         struct iscsi_session *session = conn->session;
1498         unsigned long flags;
1499
1500         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1501         mutex_lock(&conn->xmitmutex);
1502
1503         spin_lock_bh(&session->lock);
1504         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1505         if (session->leadconn == conn) {
1506                 /*
1507                  * leading connection? then give up on recovery.
1508                  */
1509                 session->state = ISCSI_STATE_TERMINATE;
1510                 wake_up(&conn->ehwait);
1511         }
1512         spin_unlock_bh(&session->lock);
1513
1514         mutex_unlock(&conn->xmitmutex);
1515
1516         /*
1517          * Block until all in-progress commands for this connection
1518          * time out or fail.
1519          */
1520         for (;;) {
1521                 spin_lock_irqsave(session->host->host_lock, flags);
1522                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1523                         spin_unlock_irqrestore(session->host->host_lock, flags);
1524                         break;
1525                 }
1526                 spin_unlock_irqrestore(session->host->host_lock, flags);
1527                 msleep_interruptible(500);
1528                 printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
1529                        "host_failed %d\n", session->host->host_busy,
1530                        session->host->host_failed);
1531                 /*
1532                  * force eh_abort() to unblock
1533                  */
1534                 wake_up(&conn->ehwait);
1535         }
1536
1537         spin_lock_bh(&session->lock);
1538         kfree(conn->data);
1539         kfree(conn->persistent_address);
1540         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1541                     sizeof(void*));
1542         list_del(&conn->item);
1543         if (list_empty(&session->connections))
1544                 session->leadconn = NULL;
1545         if (session->leadconn && session->leadconn == conn)
1546                 session->leadconn = container_of(session->connections.next,
1547                         struct iscsi_conn, item);
1548
1549         if (session->leadconn == NULL)
1550                 /* no connections exits.. reset sequencing */
1551                 session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
1552         spin_unlock_bh(&session->lock);
1553
1554         kfifo_free(conn->immqueue);
1555         kfifo_free(conn->mgmtqueue);
1556
1557         iscsi_destroy_conn(cls_conn);
1558 }
1559 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1560
1561 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1562 {
1563         struct iscsi_conn *conn = cls_conn->dd_data;
1564         struct iscsi_session *session = conn->session;
1565
1566         if (!session) {
1567                 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1568                 return -EPERM;
1569         }
1570
1571         if (session->first_burst > session->max_burst) {
1572                 printk("iscsi: invalid burst lengths: "
1573                        "first_burst %d max_burst %d\n",
1574                        session->first_burst, session->max_burst);
1575                 return -EINVAL;
1576         }
1577
1578         spin_lock_bh(&session->lock);
1579         conn->c_stage = ISCSI_CONN_STARTED;
1580         session->state = ISCSI_STATE_LOGGED_IN;
1581
1582         switch(conn->stop_stage) {
1583         case STOP_CONN_RECOVER:
1584                 /*
1585                  * unblock eh_abort() if it is blocked. re-try all
1586                  * commands after successful recovery
1587                  */
1588                 conn->stop_stage = 0;
1589                 conn->tmabort_state = TMABORT_INITIAL;
1590                 session->age++;
1591                 spin_unlock_bh(&session->lock);
1592
1593                 iscsi_unblock_session(session_to_cls(session));
1594                 wake_up(&conn->ehwait);
1595                 return 0;
1596         case STOP_CONN_TERM:
1597                 conn->stop_stage = 0;
1598                 break;
1599         default:
1600                 break;
1601         }
1602         spin_unlock_bh(&session->lock);
1603
1604         return 0;
1605 }
1606 EXPORT_SYMBOL_GPL(iscsi_conn_start);
1607
1608 static void
1609 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
1610 {
1611         struct iscsi_mgmt_task *mtask, *tmp;
1612
1613         /* handle pending */
1614         while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
1615                __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
1616                 if (mtask == conn->login_mtask)
1617                         continue;
1618                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
1619                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1620                             sizeof(void*));
1621         }
1622
1623         /* handle running */
1624         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
1625                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
1626                 list_del(&mtask->running);
1627
1628                 if (mtask == conn->login_mtask)
1629                         continue;
1630                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1631                            sizeof(void*));
1632         }
1633
1634         conn->mtask = NULL;
1635 }
1636
1637 /* Fail commands. Mutex and session lock held and recv side suspended */
1638 static void fail_all_commands(struct iscsi_conn *conn)
1639 {
1640         struct iscsi_cmd_task *ctask, *tmp;
1641
1642         /* flush pending */
1643         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1644                 debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
1645                            ctask->itt);
1646                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1647         }
1648
1649         /* fail all other running */
1650         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1651                 debug_scsi("failing in progress sc %p itt 0x%x\n",
1652                            ctask->sc, ctask->itt);
1653                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1654         }
1655
1656         conn->ctask = NULL;
1657 }
1658
1659 static void iscsi_start_session_recovery(struct iscsi_session *session,
1660                                          struct iscsi_conn *conn, int flag)
1661 {
1662         int old_stop_stage;
1663
1664         spin_lock_bh(&session->lock);
1665         if (conn->stop_stage == STOP_CONN_TERM) {
1666                 spin_unlock_bh(&session->lock);
1667                 return;
1668         }
1669
1670         /*
1671          * When this is called for the in_login state, we only want to clean
1672          * up the login task and connection. We do not need to block and set
1673          * the recovery state again
1674          */
1675         if (flag == STOP_CONN_TERM)
1676                 session->state = ISCSI_STATE_TERMINATE;
1677         else if (conn->stop_stage != STOP_CONN_RECOVER)
1678                 session->state = ISCSI_STATE_IN_RECOVERY;
1679
1680         old_stop_stage = conn->stop_stage;
1681         conn->stop_stage = flag;
1682         conn->c_stage = ISCSI_CONN_STOPPED;
1683         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1684         spin_unlock_bh(&session->lock);
1685
1686         write_lock_bh(conn->recv_lock);
1687         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1688         write_unlock_bh(conn->recv_lock);
1689
1690         mutex_lock(&conn->xmitmutex);
1691         /*
1692          * for connection level recovery we should not calculate
1693          * header digest. conn->hdr_size used for optimization
1694          * in hdr_extract() and will be re-negotiated at
1695          * set_param() time.
1696          */
1697         if (flag == STOP_CONN_RECOVER) {
1698                 conn->hdrdgst_en = 0;
1699                 conn->datadgst_en = 0;
1700                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
1701                     old_stop_stage != STOP_CONN_RECOVER) {
1702                         debug_scsi("blocking session\n");
1703                         iscsi_block_session(session_to_cls(session));
1704                 }
1705         }
1706
1707         /*
1708          * flush queues.
1709          */
1710         spin_lock_bh(&session->lock);
1711         fail_all_commands(conn);
1712         flush_control_queues(session, conn);
1713         spin_unlock_bh(&session->lock);
1714
1715         mutex_unlock(&conn->xmitmutex);
1716 }
1717
1718 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1719 {
1720         struct iscsi_conn *conn = cls_conn->dd_data;
1721         struct iscsi_session *session = conn->session;
1722
1723         switch (flag) {
1724         case STOP_CONN_RECOVER:
1725         case STOP_CONN_TERM:
1726                 iscsi_start_session_recovery(session, conn, flag);
1727                 break;
1728         default:
1729                 printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
1730         }
1731 }
1732 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
1733
1734 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
1735                     struct iscsi_cls_conn *cls_conn, int is_leading)
1736 {
1737         struct iscsi_session *session = class_to_transport_session(cls_session);
1738         struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = cls_conn->dd_data;
1739
1740         /* lookup for existing connection */
1741         spin_lock_bh(&session->lock);
1742         list_for_each_entry(tmp, &session->connections, item) {
1743                 if (tmp == conn) {
1744                         if (conn->c_stage != ISCSI_CONN_STOPPED ||
1745                             conn->stop_stage == STOP_CONN_TERM) {
1746                                 printk(KERN_ERR "iscsi: can't bind "
1747                                        "non-stopped connection (%d:%d)\n",
1748                                        conn->c_stage, conn->stop_stage);
1749                                 spin_unlock_bh(&session->lock);
1750                                 return -EIO;
1751                         }
1752                         break;
1753                 }
1754         }
1755         if (tmp != conn) {
1756                 /* bind new iSCSI connection to session */
1757                 conn->session = session;
1758                 list_add(&conn->item, &session->connections);
1759         }
1760         spin_unlock_bh(&session->lock);
1761
1762         if (is_leading)
1763                 session->leadconn = conn;
1764
1765         /*
1766          * Unblock xmitworker(), Login Phase will pass through.
1767          */
1768         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1769         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1770         return 0;
1771 }
1772 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
1773
1774
1775 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
1776                     enum iscsi_param param, char *buf, int buflen)
1777 {
1778         struct iscsi_conn *conn = cls_conn->dd_data;
1779         struct iscsi_session *session = conn->session;
1780         uint32_t value;
1781
1782         switch(param) {
1783         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1784                 sscanf(buf, "%d", &conn->max_recv_dlength);
1785                 break;
1786         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1787                 sscanf(buf, "%d", &conn->max_xmit_dlength);
1788                 break;
1789         case ISCSI_PARAM_HDRDGST_EN:
1790                 sscanf(buf, "%d", &conn->hdrdgst_en);
1791                 break;
1792         case ISCSI_PARAM_DATADGST_EN:
1793                 sscanf(buf, "%d", &conn->datadgst_en);
1794                 break;
1795         case ISCSI_PARAM_INITIAL_R2T_EN:
1796                 sscanf(buf, "%d", &session->initial_r2t_en);
1797                 break;
1798         case ISCSI_PARAM_MAX_R2T:
1799                 sscanf(buf, "%d", &session->max_r2t);
1800                 break;
1801         case ISCSI_PARAM_IMM_DATA_EN:
1802                 sscanf(buf, "%d", &session->imm_data_en);
1803                 break;
1804         case ISCSI_PARAM_FIRST_BURST:
1805                 sscanf(buf, "%d", &session->first_burst);
1806                 break;
1807         case ISCSI_PARAM_MAX_BURST:
1808                 sscanf(buf, "%d", &session->max_burst);
1809                 break;
1810         case ISCSI_PARAM_PDU_INORDER_EN:
1811                 sscanf(buf, "%d", &session->pdu_inorder_en);
1812                 break;
1813         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1814                 sscanf(buf, "%d", &session->dataseq_inorder_en);
1815                 break;
1816         case ISCSI_PARAM_ERL:
1817                 sscanf(buf, "%d", &session->erl);
1818                 break;
1819         case ISCSI_PARAM_IFMARKER_EN:
1820                 sscanf(buf, "%d", &value);
1821                 BUG_ON(value);
1822                 break;
1823         case ISCSI_PARAM_OFMARKER_EN:
1824                 sscanf(buf, "%d", &value);
1825                 BUG_ON(value);
1826                 break;
1827         case ISCSI_PARAM_EXP_STATSN:
1828                 sscanf(buf, "%u", &conn->exp_statsn);
1829                 break;
1830         case ISCSI_PARAM_TARGET_NAME:
1831                 /* this should not change between logins */
1832                 if (session->targetname)
1833                         break;
1834
1835                 session->targetname = kstrdup(buf, GFP_KERNEL);
1836                 if (!session->targetname)
1837                         return -ENOMEM;
1838                 break;
1839         case ISCSI_PARAM_TPGT:
1840                 sscanf(buf, "%d", &session->tpgt);
1841                 break;
1842         case ISCSI_PARAM_PERSISTENT_PORT:
1843                 sscanf(buf, "%d", &conn->persistent_port);
1844                 break;
1845         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1846                 /*
1847                  * this is the address returned in discovery so it should
1848                  * not change between logins.
1849                  */
1850                 if (conn->persistent_address)
1851                         break;
1852
1853                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
1854                 if (!conn->persistent_address)
1855                         return -ENOMEM;
1856                 break;
1857         default:
1858                 return -ENOSYS;
1859         }
1860
1861         return 0;
1862 }
1863 EXPORT_SYMBOL_GPL(iscsi_set_param);
1864
1865 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
1866                             enum iscsi_param param, char *buf)
1867 {
1868         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1869         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1870         int len;
1871
1872         switch(param) {
1873         case ISCSI_PARAM_INITIAL_R2T_EN:
1874                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
1875                 break;
1876         case ISCSI_PARAM_MAX_R2T:
1877                 len = sprintf(buf, "%hu\n", session->max_r2t);
1878                 break;
1879         case ISCSI_PARAM_IMM_DATA_EN:
1880                 len = sprintf(buf, "%d\n", session->imm_data_en);
1881                 break;
1882         case ISCSI_PARAM_FIRST_BURST:
1883                 len = sprintf(buf, "%u\n", session->first_burst);
1884                 break;
1885         case ISCSI_PARAM_MAX_BURST:
1886                 len = sprintf(buf, "%u\n", session->max_burst);
1887                 break;
1888         case ISCSI_PARAM_PDU_INORDER_EN:
1889                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
1890                 break;
1891         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1892                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
1893                 break;
1894         case ISCSI_PARAM_ERL:
1895                 len = sprintf(buf, "%d\n", session->erl);
1896                 break;
1897         case ISCSI_PARAM_TARGET_NAME:
1898                 len = sprintf(buf, "%s\n", session->targetname);
1899                 break;
1900         case ISCSI_PARAM_TPGT:
1901                 len = sprintf(buf, "%d\n", session->tpgt);
1902                 break;
1903         default:
1904                 return -ENOSYS;
1905         }
1906
1907         return len;
1908 }
1909 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
1910
1911 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
1912                          enum iscsi_param param, char *buf)
1913 {
1914         struct iscsi_conn *conn = cls_conn->dd_data;
1915         int len;
1916
1917         switch(param) {
1918         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1919                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
1920                 break;
1921         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1922                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
1923                 break;
1924         case ISCSI_PARAM_HDRDGST_EN:
1925                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
1926                 break;
1927         case ISCSI_PARAM_DATADGST_EN:
1928                 len = sprintf(buf, "%d\n", conn->datadgst_en);
1929                 break;
1930         case ISCSI_PARAM_IFMARKER_EN:
1931                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
1932                 break;
1933         case ISCSI_PARAM_OFMARKER_EN:
1934                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
1935                 break;
1936         case ISCSI_PARAM_EXP_STATSN:
1937                 len = sprintf(buf, "%u\n", conn->exp_statsn);
1938                 break;
1939         case ISCSI_PARAM_PERSISTENT_PORT:
1940                 len = sprintf(buf, "%d\n", conn->persistent_port);
1941                 break;
1942         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1943                 len = sprintf(buf, "%s\n", conn->persistent_address);
1944                 break;
1945         default:
1946                 return -ENOSYS;
1947         }
1948
1949         return len;
1950 }
1951 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
1952
1953 MODULE_AUTHOR("Mike Christie");
1954 MODULE_DESCRIPTION("iSCSI library functions");
1955 MODULE_LICENSE("GPL");