SAFE public projects git trees. - safe/jmp/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         /* SCSI eh reuses commands to verify us */
 196         sc->SCp.ptr = NULL;
 197         list_del_init(&ctask->running);
 198         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
 199         sc->scsi_done(sc);
 200 }
 201
 202 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
 203 {
 204         atomic_inc(&ctask->refcount);
 205 }
 206
 207 static void iscsi_get_ctask(struct iscsi_cmd_task *ctask)
 208 {
 209         spin_lock_bh(&ctask->conn->session->lock);
 210         __iscsi_get_ctask(ctask);
 211         spin_unlock_bh(&ctask->conn->session->lock);
 212 }
 213
 214 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
 215 {
 216         if (atomic_dec_and_test(&ctask->refcount))
 217                 iscsi_complete_command(ctask);
 218 }
 219
 220 static void iscsi_put_ctask(struct iscsi_cmd_task *ctask)
 221 {
 222         spin_lock_bh(&ctask->conn->session->lock);
 223         __iscsi_put_ctask(ctask);
 224         spin_unlock_bh(&ctask->conn->session->lock);
 225 }
 226
 227 /**
 228  * iscsi_cmd_rsp - SCSI Command Response processing
 229  * @conn: iscsi connection
 230  * @hdr: iscsi header
 231  * @ctask: scsi command task
 232  * @data: cmd data buffer
 233  * @datalen: len of buffer
 234  *
 235  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 236  * then completes the command and task.
 237  **/
 238 static int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 239                               struct iscsi_cmd_task *ctask, char *data,
 240                               int datalen)
 241 {
 242         int rc;
 243         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
 244         struct iscsi_session *session = conn->session;
 245         struct scsi_cmnd *sc = ctask->sc;
 246
 247         rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
 248         if (rc) {
 249                 sc->result = DID_ERROR << 16;
 250                 goto out;
 251         }
 252
 253         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 254
 255         sc->result = (DID_OK << 16) | rhdr->cmd_status;
 256
 257         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 258                 sc->result = DID_ERROR << 16;
 259                 goto out;
 260         }
 261
 262         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 263                 int senselen;
 264
 265                 if (datalen < 2) {
 266 invalid_datalen:
 267                         printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
 268                                "invalid data buffer size of %d\n", datalen);
 269                         sc->result = DID_BAD_TARGET << 16;
 270                         goto out;
 271                 }
 272
 273                 senselen = (data[0] << 8) | data[1];
 274                 if (datalen < senselen)
 275                         goto invalid_datalen;
 276
 277                 memcpy(sc->sense_buffer, data + 2,
 278                        min(senselen, SCSI_SENSE_BUFFERSIZE));
 279                 debug_scsi("copied %d bytes of sense\n",
 280                            min(senselen, SCSI_SENSE_BUFFERSIZE));
 281         }
 282
 283         if (sc->sc_data_direction == DMA_TO_DEVICE)
 284                 goto out;
 285
 286         if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
 287                 int res_count = be32_to_cpu(rhdr->residual_count);
 288
 289                 if (res_count > 0 && res_count <= sc->request_bufflen)
 290                         sc->resid = res_count;
 291                 else
 292                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 293         } else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
 294                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 295         else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW)
 296                 sc->resid = be32_to_cpu(rhdr->residual_count);
 297
 298 out:
 299         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
 300                    (long)sc, sc->result, ctask->itt);
 301         conn->scsirsp_pdus_cnt++;
 302
 303         __iscsi_put_ctask(ctask);
 304         return rc;
 305 }
 306
 307 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 308 {
 309         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 310
 311         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 312         conn->tmfrsp_pdus_cnt++;
 313
 314         if (conn->tmabort_state != TMABORT_INITIAL)
 315                 return;
 316
 317         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 318                 conn->tmabort_state = TMABORT_SUCCESS;
 319         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 320                 conn->tmabort_state = TMABORT_NOT_FOUND;
 321         else
 322                 conn->tmabort_state = TMABORT_FAILED;
 323         wake_up(&conn->ehwait);
 324 }
 325
 326 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 327                                char *data, int datalen)
 328 {
 329         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
 330         struct iscsi_hdr rejected_pdu;
 331         uint32_t itt;
 332
 333         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
 334
 335         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
 336                 if (ntoh24(reject->dlength) > datalen)
 337                         return ISCSI_ERR_PROTO;
 338
 339                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
 340                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
 341                         itt = rejected_pdu.itt & ISCSI_ITT_MASK;
 342                         printk(KERN_ERR "itt 0x%x had pdu (op 0x%x) rejected "
 343                                 "due to DataDigest error.\n", itt,
 344                                 rejected_pdu.opcode);
 345                 }
 346         }
 347         return 0;
 348 }
 349
 350 /**
 351  * __iscsi_complete_pdu - complete pdu
 352  * @conn: iscsi conn
 353  * @hdr: iscsi header
 354  * @data: data buffer
 355  * @datalen: len of data buffer
 356  *
 357  * Completes pdu processing by freeing any resources allocated at
 358  * queuecommand or send generic. session lock must be held and verify
 359  * itt must have been called.
 360  */
 361 int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 362                          char *data, int datalen)
 363 {
 364         struct iscsi_session *session = conn->session;
 365         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
 366         struct iscsi_cmd_task *ctask;
 367         struct iscsi_mgmt_task *mtask;
 368         uint32_t itt;
 369
 370         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG))
 371                 itt = hdr->itt & ISCSI_ITT_MASK;
 372         else
 373                 itt = hdr->itt;
 374
 375         if (itt < session->cmds_max) {
 376                 ctask = session->cmds[itt];
 377
 378                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 379                            opcode, conn->id, ctask->itt, datalen);
 380
 381                 switch(opcode) {
 382                 case ISCSI_OP_SCSI_CMD_RSP:
 383                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 384                         rc = iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
 385                                                 datalen);
 386                         break;
 387                 case ISCSI_OP_SCSI_DATA_IN:
 388                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 389                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
 390                                 conn->scsirsp_pdus_cnt++;
 391                                 __iscsi_put_ctask(ctask);
 392                         }
 393                         break;
 394                 case ISCSI_OP_R2T:
 395                         /* LLD handles this for now */
 396                         break;
 397                 default:
 398                         rc = ISCSI_ERR_BAD_OPCODE;
 399                         break;
 400                 }
 401         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
 402                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
 403                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
 404
 405                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 406                            opcode, conn->id, mtask->itt, datalen);
 407
 408                 rc = iscsi_check_assign_cmdsn(session,
 409                                               (struct iscsi_nopin*)hdr);
 410                 if (rc)
 411                         goto done;
 412
 413                 switch(opcode) {
 414                 case ISCSI_OP_LOGOUT_RSP:
 415                         if (datalen) {
 416                                 rc = ISCSI_ERR_PROTO;
 417                                 break;
 418                         }
 419                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 420                         /* fall through */
 421                 case ISCSI_OP_LOGIN_RSP:
 422                 case ISCSI_OP_TEXT_RSP:
 423                         /*
 424                          * login related PDU's exp_statsn is handled in
 425                          * userspace
 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                 case ISCSI_OP_SCSI_TMFUNC_RSP:
 435                         if (datalen) {
 436                                 rc = ISCSI_ERR_PROTO;
 437                                 break;
 438                         }
 439
 440                         iscsi_tmf_rsp(conn, hdr);
 441                         break;
 442                 case ISCSI_OP_NOOP_IN:
 443                         if (hdr->ttt != ISCSI_RESERVED_TAG || datalen) {
 444                                 rc = ISCSI_ERR_PROTO;
 445                                 break;
 446                         }
 447                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 448
 449                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 450                                 rc = ISCSI_ERR_CONN_FAILED;
 451                         list_del(&mtask->running);
 452                         if (conn->login_mtask != mtask)
 453                                 __kfifo_put(session->mgmtpool.queue,
 454                                             (void*)&mtask, sizeof(void*));
 455                         break;
 456                 default:
 457                         rc = ISCSI_ERR_BAD_OPCODE;
 458                         break;
 459                 }
 460         } else if (itt == ISCSI_RESERVED_TAG) {
 461                 rc = iscsi_check_assign_cmdsn(session,
 462                                              (struct iscsi_nopin*)hdr);
 463                 if (rc)
 464                         goto done;
 465
 466                 switch(opcode) {
 467                 case ISCSI_OP_NOOP_IN:
 468                         if (datalen) {
 469                                 rc = ISCSI_ERR_PROTO;
 470                                 break;
 471                         }
 472
 473                         if (hdr->ttt == ISCSI_RESERVED_TAG)
 474                                 break;
 475
 476                         if (iscsi_recv_pdu(conn->cls_conn, hdr, NULL, 0))
 477                                 rc = ISCSI_ERR_CONN_FAILED;
 478                         break;
 479                 case ISCSI_OP_REJECT:
 480                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
 481                         break;
 482                 case ISCSI_OP_ASYNC_EVENT:
 483                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 484                         /* we need sth like iscsi_async_event_rsp() */
 485                         rc = ISCSI_ERR_BAD_OPCODE;
 486                         break;
 487                 default:
 488                         rc = ISCSI_ERR_BAD_OPCODE;
 489                         break;
 490                 }
 491         } else
 492                 rc = ISCSI_ERR_BAD_ITT;
 493
 494 done:
 495         return rc;
 496 }
 497 EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
 498
 499 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 500                        char *data, int datalen)
 501 {
 502         int rc;
 503
 504         spin_lock(&conn->session->lock);
 505         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
 506         spin_unlock(&conn->session->lock);
 507         return rc;
 508 }
 509 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 510
 511 /* verify itt (itt encoding: age+cid+itt) */
 512 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 513                      uint32_t *ret_itt)
 514 {
 515         struct iscsi_session *session = conn->session;
 516         struct iscsi_cmd_task *ctask;
 517         uint32_t itt;
 518
 519         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
 520                 if ((hdr->itt & ISCSI_AGE_MASK) !=
 521                     (session->age << ISCSI_AGE_SHIFT)) {
 522                         printk(KERN_ERR "iscsi: received itt %x expected "
 523                                 "session age (%x)\n", hdr->itt,
 524                                 session->age & ISCSI_AGE_MASK);
 525                         return ISCSI_ERR_BAD_ITT;
 526                 }
 527
 528                 if ((hdr->itt & ISCSI_CID_MASK) !=
 529                     (conn->id << ISCSI_CID_SHIFT)) {
 530                         printk(KERN_ERR "iscsi: received itt %x, expected "
 531                                 "CID (%x)\n", hdr->itt, conn->id);
 532                         return ISCSI_ERR_BAD_ITT;
 533                 }
 534                 itt = hdr->itt & ISCSI_ITT_MASK;
 535         } else
 536                 itt = hdr->itt;
 537
 538         if (itt < session->cmds_max) {
 539                 ctask = session->cmds[itt];
 540
 541                 if (!ctask->sc) {
 542                         printk(KERN_INFO "iscsi: dropping ctask with "
 543                                "itt 0x%x\n", ctask->itt);
 544                         /* force drop */
 545                         return ISCSI_ERR_NO_SCSI_CMD;
 546                 }
 547
 548                 if (ctask->sc->SCp.phase != session->age) {
 549                         printk(KERN_ERR "iscsi: ctask's session age %d, "
 550                                 "expected %d\n", ctask->sc->SCp.phase,
 551                                 session->age);
 552                         return ISCSI_ERR_SESSION_FAILED;
 553                 }
 554         }
 555
 556         *ret_itt = itt;
 557         return 0;
 558 }
 559 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 560
 561 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 562 {
 563         struct iscsi_session *session = conn->session;
 564         unsigned long flags;
 565
 566         spin_lock_irqsave(&session->lock, flags);
 567         if (session->state == ISCSI_STATE_FAILED) {
 568                 spin_unlock_irqrestore(&session->lock, flags);
 569                 return;
 570         }
 571
 572         if (conn->stop_stage == 0)
 573                 session->state = ISCSI_STATE_FAILED;
 574         spin_unlock_irqrestore(&session->lock, flags);
 575         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 576         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 577         iscsi_conn_error(conn->cls_conn, err);
 578 }
 579 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 580
 581 /**
 582  * iscsi_data_xmit - xmit any command into the scheduled connection
 583  * @conn: iscsi connection
 584  *
 585  * Notes:
 586  *      The function can return -EAGAIN in which case the caller must
 587  *      re-schedule it again later or recover. '0' return code means
 588  *      successful xmit.
 589  **/
 590 static int iscsi_data_xmit(struct iscsi_conn *conn)
 591 {
 592         struct iscsi_transport *tt;
 593         int rc = 0;
 594
 595         if (unlikely(conn->suspend_tx)) {
 596                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 597                 return -ENODATA;
 598         }
 599         tt = conn->session->tt;
 600
 601         /*
 602          * Transmit in the following order:
 603          *
 604          * 1) un-finished xmit (ctask or mtask)
 605          * 2) immediate control PDUs
 606          * 3) write data
 607          * 4) SCSI commands
 608          * 5) non-immediate control PDUs
 609          *
 610          * No need to lock around __kfifo_get as long as
 611          * there's one producer and one consumer.
 612          */
 613
 614         BUG_ON(conn->ctask && conn->mtask);
 615
 616         if (conn->ctask) {
 617                 iscsi_get_ctask(conn->ctask);
 618                 rc = tt->xmit_cmd_task(conn, conn->ctask);
 619                 iscsi_put_ctask(conn->ctask);
 620                 if (rc)
 621                         goto again;
 622                 /* done with this in-progress ctask */
 623                 conn->ctask = NULL;
 624         }
 625         if (conn->mtask) {
 626                 rc = tt->xmit_mgmt_task(conn, conn->mtask);
 627                 if (rc)
 628                         goto again;
 629                 /* done with this in-progress mtask */
 630                 conn->mtask = NULL;
 631         }
 632
 633         /* process immediate first */
 634         if (unlikely(__kfifo_len(conn->immqueue))) {
 635                 while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
 636                                    sizeof(void*))) {
 637                         spin_lock_bh(&conn->session->lock);
 638                         list_add_tail(&conn->mtask->running,
 639                                       &conn->mgmt_run_list);
 640                         spin_unlock_bh(&conn->session->lock);
 641                         rc = tt->xmit_mgmt_task(conn, conn->mtask);
 642                         if (rc)
 643                                 goto again;
 644                 }
 645                 /* done with this mtask */
 646                 conn->mtask = NULL;
 647         }
 648
 649         /* process command queue */
 650         spin_lock_bh(&conn->session->lock);
 651         while (!list_empty(&conn->xmitqueue)) {
 652                 /*
 653                  * iscsi tcp may readd the task to the xmitqueue to send
 654                  * write data
 655                  */
 656                 conn->ctask = list_entry(conn->xmitqueue.next,
 657                                          struct iscsi_cmd_task, running);
 658                 conn->ctask->state = ISCSI_TASK_RUNNING;
 659                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
 660                 __iscsi_get_ctask(conn->ctask);
 661                 spin_unlock_bh(&conn->session->lock);
 662
 663                 rc = tt->xmit_cmd_task(conn, conn->ctask);
 664                 if (rc)
 665                         goto again;
 666
 667                 spin_lock_bh(&conn->session->lock);
 668                 __iscsi_put_ctask(conn->ctask);
 669                 if (rc) {
 670                         spin_unlock_bh(&conn->session->lock);
 671                         goto again;
 672                 }
 673         }
 674         spin_unlock_bh(&conn->session->lock);
 675         /* done with this ctask */
 676         conn->ctask = NULL;
 677
 678         /* process the rest control plane PDUs, if any */
 679         if (unlikely(__kfifo_len(conn->mgmtqueue))) {
 680                 while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
 681                                    sizeof(void*))) {
 682                         spin_lock_bh(&conn->session->lock);
 683                         list_add_tail(&conn->mtask->running,
 684                                       &conn->mgmt_run_list);
 685                         spin_unlock_bh(&conn->session->lock);
 686                         rc = tt->xmit_mgmt_task(conn, conn->mtask);
 687                         if (rc)
 688                                 goto again;
 689                 }
 690                 /* done with this mtask */
 691                 conn->mtask = NULL;
 692         }
 693
 694         return -ENODATA;
 695
 696 again:
 697         if (unlikely(conn->suspend_tx))
 698                 return -ENODATA;
 699
 700         return rc;
 701 }
 702
 703 static void iscsi_xmitworker(void *data)
 704 {
 705         struct iscsi_conn *conn = data;
 706         int rc;
 707         /*
 708          * serialize Xmit worker on a per-connection basis.
 709          */
 710         mutex_lock(&conn->xmitmutex);
 711         do {
 712                 rc = iscsi_data_xmit(conn);
 713         } while (rc >= 0 || rc == -EAGAIN);
 714         mutex_unlock(&conn->xmitmutex);
 715 }
 716
 717 enum {
 718         FAILURE_BAD_HOST = 1,
 719         FAILURE_SESSION_FAILED,
 720         FAILURE_SESSION_FREED,
 721         FAILURE_WINDOW_CLOSED,
 722         FAILURE_OOM,
 723         FAILURE_SESSION_TERMINATE,
 724         FAILURE_SESSION_IN_RECOVERY,
 725         FAILURE_SESSION_RECOVERY_TIMEOUT,
 726 };
 727
 728 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 729 {
 730         struct Scsi_Host *host;
 731         int reason = 0;
 732         struct iscsi_session *session;
 733         struct iscsi_conn *conn;
 734         struct iscsi_cmd_task *ctask = NULL;
 735
 736         sc->scsi_done = done;
 737         sc->result = 0;
 738         sc->SCp.ptr = NULL;
 739
 740         host = sc->device->host;
 741         session = iscsi_hostdata(host->hostdata);
 742
 743         spin_lock(&session->lock);
 744
 745         /*
 746          * ISCSI_STATE_FAILED is a temp. state. The recovery
 747          * code will decide what is best to do with command queued
 748          * during this time
 749          */
 750         if (session->state != ISCSI_STATE_LOGGED_IN &&
 751             session->state != ISCSI_STATE_FAILED) {
 752                 /*
 753                  * to handle the race between when we set the recovery state
 754                  * and block the session we requeue here (commands could
 755                  * be entering our queuecommand while a block is starting
 756                  * up because the block code is not locked)
 757                  */
 758                 if (session->state == ISCSI_STATE_IN_RECOVERY) {
 759                         reason = FAILURE_SESSION_IN_RECOVERY;
 760                         goto reject;
 761                 }
 762
 763                 if (session->state == ISCSI_STATE_RECOVERY_FAILED)
 764                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
 765                 else if (session->state == ISCSI_STATE_TERMINATE)
 766                         reason = FAILURE_SESSION_TERMINATE;
 767                 else
 768                         reason = FAILURE_SESSION_FREED;
 769                 goto fault;
 770         }
 771
 772         /*
 773          * Check for iSCSI window and take care of CmdSN wrap-around
 774          */
 775         if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
 776                 reason = FAILURE_WINDOW_CLOSED;
 777                 goto reject;
 778         }
 779
 780         conn = session->leadconn;
 781         if (!conn) {
 782                 reason = FAILURE_SESSION_FREED;
 783                 goto fault;
 784         }
 785
 786         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
 787                          sizeof(void*))) {
 788                 reason = FAILURE_OOM;
 789                 goto reject;
 790         }
 791         sc->SCp.phase = session->age;
 792         sc->SCp.ptr = (char *)ctask;
 793
 794         atomic_set(&ctask->refcount, 1);
 795         ctask->state = ISCSI_TASK_PENDING;
 796         ctask->mtask = NULL;
 797         ctask->conn = conn;
 798         ctask->sc = sc;
 799         INIT_LIST_HEAD(&ctask->running);
 800         ctask->total_length = sc->request_bufflen;
 801         iscsi_prep_scsi_cmd_pdu(ctask);
 802
 803         session->tt->init_cmd_task(ctask);
 804
 805         list_add_tail(&ctask->running, &conn->xmitqueue);
 806         debug_scsi(
 807                "ctask enq [%s cid %d sc %p cdb 0x%x itt 0x%x len %d cmdsn %d "
 808                 "win %d]\n",
 809                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
 810                 conn->id, sc, sc->cmnd[0], ctask->itt, sc->request_bufflen,
 811                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 812         spin_unlock(&session->lock);
 813
 814         scsi_queue_work(host, &conn->xmitwork);
 815         return 0;
 816
 817 reject:
 818         spin_unlock(&session->lock);
 819         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
 820         return SCSI_MLQUEUE_HOST_BUSY;
 821
 822 fault:
 823         spin_unlock(&session->lock);
 824         printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
 825                sc->cmnd[0], reason);
 826         sc->result = (DID_NO_CONNECT << 16);
 827         sc->resid = sc->request_bufflen;
 828         sc->scsi_done(sc);
 829         return 0;
 830 }
 831 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
 832
 833 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
 834 {
 835         if (depth > ISCSI_MAX_CMD_PER_LUN)
 836                 depth = ISCSI_MAX_CMD_PER_LUN;
 837         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 838         return sdev->queue_depth;
 839 }
 840 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
 841
 842 static int
 843 iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 844                         char *data, uint32_t data_size)
 845 {
 846         struct iscsi_session *session = conn->session;
 847         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 848         struct iscsi_mgmt_task *mtask;
 849
 850         spin_lock_bh(&session->lock);
 851         if (session->state == ISCSI_STATE_TERMINATE) {
 852                 spin_unlock_bh(&session->lock);
 853                 return -EPERM;
 854         }
 855         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
 856             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 857                 /*
 858                  * Login and Text are sent serially, in
 859                  * request-followed-by-response sequence.
 860                  * Same mtask can be used. Same ITT must be used.
 861                  * Note that login_mtask is preallocated at conn_create().
 862                  */
 863                 mtask = conn->login_mtask;
 864         else {
 865                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 866                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 867
 868                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 869                 if (!__kfifo_get(session->mgmtpool.queue,
 870                                  (void*)&mtask, sizeof(void*))) {
 871                         spin_unlock_bh(&session->lock);
 872                         return -ENOSPC;
 873                 }
 874         }
 875
 876         /*
 877          * pre-format CmdSN for outgoing PDU.
 878          */
 879         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
 880                 hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) |
 881                            (session->age << ISCSI_AGE_SHIFT);
 882                 nop->cmdsn = cpu_to_be32(session->cmdsn);
 883                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 884                     !(hdr->opcode & ISCSI_OP_IMMEDIATE))
 885                         session->cmdsn++;
 886         } else
 887                 /* do not advance CmdSN */
 888                 nop->cmdsn = cpu_to_be32(session->cmdsn);
 889
 890         if (data_size) {
 891                 memcpy(mtask->data, data, data_size);
 892                 mtask->data_count = data_size;
 893         } else
 894                 mtask->data_count = 0;
 895
 896         INIT_LIST_HEAD(&mtask->running);
 897         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
 898         if (session->tt->init_mgmt_task)
 899                 session->tt->init_mgmt_task(conn, mtask, data, data_size);
 900         spin_unlock_bh(&session->lock);
 901
 902         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 903                    hdr->opcode, hdr->itt, data_size);
 904
 905         /*
 906          * since send_pdu() could be called at least from two contexts,
 907          * we need to serialize __kfifo_put, so we don't have to take
 908          * additional lock on fast data-path
 909          */
 910         if (hdr->opcode & ISCSI_OP_IMMEDIATE)
 911                 __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
 912         else
 913                 __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
 914
 915         scsi_queue_work(session->host, &conn->xmitwork);
 916         return 0;
 917 }
 918
 919 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 920                         char *data, uint32_t data_size)
 921 {
 922         struct iscsi_conn *conn = cls_conn->dd_data;
 923         int rc;
 924
 925         mutex_lock(&conn->xmitmutex);
 926         rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
 927         mutex_unlock(&conn->xmitmutex);
 928
 929         return rc;
 930 }
 931 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 932
 933 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
 934 {
 935         struct iscsi_session *session = class_to_transport_session(cls_session);
 936         struct iscsi_conn *conn = session->leadconn;
 937
 938         spin_lock_bh(&session->lock);
 939         if (session->state != ISCSI_STATE_LOGGED_IN) {
 940                 session->state = ISCSI_STATE_RECOVERY_FAILED;
 941                 if (conn)
 942                         wake_up(&conn->ehwait);
 943         }
 944         spin_unlock_bh(&session->lock);
 945 }
 946 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
 947
 948 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
 949 {
 950         struct Scsi_Host *host = sc->device->host;
 951         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
 952         struct iscsi_conn *conn = session->leadconn;
 953         int fail_session = 0;
 954
 955         spin_lock_bh(&session->lock);
 956         if (session->state == ISCSI_STATE_TERMINATE) {
 957 failed:
 958                 debug_scsi("failing host reset: session terminated "
 959                            "[CID %d age %d]", conn->id, session->age);
 960                 spin_unlock_bh(&session->lock);
 961                 return FAILED;
 962         }
 963
 964         if (sc->SCp.phase == session->age) {
 965                 debug_scsi("failing connection CID %d due to SCSI host reset",
 966                            conn->id);
 967                 fail_session = 1;
 968         }
 969         spin_unlock_bh(&session->lock);
 970
 971         /*
 972          * we drop the lock here but the leadconn cannot be destoyed while
 973          * we are in the scsi eh
 974          */
 975         if (fail_session)
 976                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 977
 978         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
 979         wait_event_interruptible(conn->ehwait,
 980                                  session->state == ISCSI_STATE_TERMINATE ||
 981                                  session->state == ISCSI_STATE_LOGGED_IN ||
 982                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
 983         if (signal_pending(current))
 984                 flush_signals(current);
 985
 986         spin_lock_bh(&session->lock);
 987         if (session->state == ISCSI_STATE_LOGGED_IN)
 988                 printk(KERN_INFO "iscsi: host reset succeeded\n");
 989         else
 990                 goto failed;
 991         spin_unlock_bh(&session->lock);
 992
 993         return SUCCESS;
 994 }
 995 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
 996
 997 static void iscsi_tmabort_timedout(unsigned long data)
 998 {
 999         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
1000         struct iscsi_conn *conn = ctask->conn;
1001         struct iscsi_session *session = conn->session;
1002
1003         spin_lock(&session->lock);
1004         if (conn->tmabort_state == TMABORT_INITIAL) {
1005                 conn->tmabort_state = TMABORT_TIMEDOUT;
1006                 debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
1007                         ctask->sc, ctask->itt);
1008                 /* unblock eh_abort() */
1009                 wake_up(&conn->ehwait);
1010         }
1011         spin_unlock(&session->lock);
1012 }
1013
1014 /* must be called with the mutex lock */
1015 static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
1016                                  struct iscsi_cmd_task *ctask)
1017 {
1018         struct iscsi_conn *conn = ctask->conn;
1019         struct iscsi_session *session = conn->session;
1020         struct iscsi_tm *hdr = &conn->tmhdr;
1021         int rc;
1022
1023         /*
1024          * ctask timed out but session is OK requests must be serialized.
1025          */
1026         memset(hdr, 0, sizeof(struct iscsi_tm));
1027         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1028         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
1029         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1030         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1031         hdr->rtt = ctask->hdr->itt;
1032         hdr->refcmdsn = ctask->hdr->cmdsn;
1033
1034         rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
1035                                      NULL, 0);
1036         if (rc) {
1037                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1038                 debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc);
1039                 return rc;
1040         }
1041
1042         debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
1043
1044         spin_lock_bh(&session->lock);
1045         ctask->mtask = (struct iscsi_mgmt_task *)
1046                         session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) -
1047                                         ISCSI_MGMT_ITT_OFFSET];
1048
1049         if (conn->tmabort_state == TMABORT_INITIAL) {
1050                 conn->tmfcmd_pdus_cnt++;
1051                 conn->tmabort_timer.expires = 10*HZ + jiffies;
1052                 conn->tmabort_timer.function = iscsi_tmabort_timedout;
1053                 conn->tmabort_timer.data = (unsigned long)ctask;
1054                 add_timer(&conn->tmabort_timer);
1055                 debug_scsi("abort set timeout [itt 0x%x]", ctask->itt);
1056         }
1057         spin_unlock_bh(&session->lock);
1058         mutex_unlock(&conn->xmitmutex);
1059
1060         /*
1061          * block eh thread until:
1062          *
1063          * 1) abort response
1064          * 2) abort timeout
1065          * 3) session is terminated or restarted or userspace has
1066          * given up on recovery
1067          */
1068         wait_event_interruptible(conn->ehwait,
1069                                  sc->SCp.phase != session->age ||
1070                                  session->state != ISCSI_STATE_LOGGED_IN ||
1071                                  conn->tmabort_state != TMABORT_INITIAL);
1072         if (signal_pending(current))
1073                 flush_signals(current);
1074         del_timer_sync(&conn->tmabort_timer);
1075
1076         mutex_lock(&conn->xmitmutex);
1077         return 0;
1078 }
1079
1080 /*
1081  * xmit mutex and session lock must be held
1082  */
1083 static struct iscsi_mgmt_task *
1084 iscsi_remove_mgmt_task(struct kfifo *fifo, uint32_t itt)
1085 {
1086         int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);
1087         struct iscsi_mgmt_task *task;
1088
1089         debug_scsi("searching %d tasks\n", nr_tasks);
1090
1091         for (i = 0; i < nr_tasks; i++) {
1092                 __kfifo_get(fifo, (void*)&task, sizeof(void*));
1093                 debug_scsi("check task %u\n", task->itt);
1094
1095                 if (task->itt == itt) {
1096                         debug_scsi("matched task\n");
1097                         return task;
1098                 }
1099
1100                 __kfifo_put(fifo, (void*)&task, sizeof(void*));
1101         }
1102         return NULL;
1103 }
1104
1105 static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
1106 {
1107         struct iscsi_conn *conn = ctask->conn;
1108         struct iscsi_session *session = conn->session;
1109
1110         if (!ctask->mtask)
1111                 return -EINVAL;
1112
1113         if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
1114                 list_del(&ctask->mtask->running);
1115         __kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
1116                     sizeof(void*));
1117         ctask->mtask = NULL;
1118         return 0;
1119 }
1120
1121 /*
1122  * session lock and xmitmutex must be held
1123  */
1124 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1125                          int err)
1126 {
1127         struct scsi_cmnd *sc;
1128
1129         sc = ctask->sc;
1130         if (!sc)
1131                 return;
1132
1133         conn->session->tt->cleanup_cmd_task(conn, ctask);
1134         iscsi_ctask_mtask_cleanup(ctask);
1135
1136         sc->result = err;
1137         sc->resid = sc->request_bufflen;
1138         /* release ref from queuecommand */
1139         __iscsi_put_ctask(ctask);
1140 }
1141
1142 int iscsi_eh_abort(struct scsi_cmnd *sc)
1143 {
1144         struct iscsi_cmd_task *ctask;
1145         struct iscsi_conn *conn;
1146         struct iscsi_session *session;
1147         int rc;
1148
1149         /*
1150          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1151          * got the command.
1152          */
1153         if (!sc->SCp.ptr) {
1154                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1155                 return SUCCESS;
1156         }
1157
1158         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1159         conn = ctask->conn;
1160         session = conn->session;
1161
1162         conn->eh_abort_cnt++;
1163         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1164
1165         mutex_lock(&conn->xmitmutex);
1166         spin_lock_bh(&session->lock);
1167
1168         /*
1169          * If we are not logged in or we have started a new session
1170          * then let the host reset code handle this
1171          */
1172         if (session->state != ISCSI_STATE_LOGGED_IN ||
1173             sc->SCp.phase != session->age)
1174                 goto failed;
1175
1176         /* ctask completed before time out */
1177         if (!ctask->sc) {
1178                 spin_unlock_bh(&session->lock);
1179                 debug_scsi("sc completed while abort in progress\n");
1180                 goto success_rel_mutex;
1181         }
1182
1183         /* what should we do here ? */
1184         if (conn->ctask == ctask) {
1185                 printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. "
1186                        "Failing abort\n", sc, ctask->itt);
1187                 goto failed;
1188         }
1189
1190         if (ctask->state == ISCSI_TASK_PENDING)
1191                 goto success_cleanup;
1192
1193         conn->tmabort_state = TMABORT_INITIAL;
1194
1195         spin_unlock_bh(&session->lock);
1196         rc = iscsi_exec_abort_task(sc, ctask);
1197         spin_lock_bh(&session->lock);
1198
1199         if (rc || sc->SCp.phase != session->age ||
1200             session->state != ISCSI_STATE_LOGGED_IN)
1201                 goto failed;
1202         iscsi_ctask_mtask_cleanup(ctask);
1203
1204         switch (conn->tmabort_state) {
1205         case TMABORT_SUCCESS:
1206                 goto success_cleanup;
1207         case TMABORT_NOT_FOUND:
1208                 if (!ctask->sc) {
1209                         /* ctask completed before tmf abort response */
1210                         spin_unlock_bh(&session->lock);
1211                         debug_scsi("sc completed while abort in progress\n");
1212                         goto success_rel_mutex;
1213                 }
1214                 /* fall through */
1215         default:
1216                 /* timedout or failed */
1217                 spin_unlock_bh(&session->lock);
1218                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1219                 spin_lock_bh(&session->lock);
1220                 goto failed;
1221         }
1222
1223 success_cleanup:
1224         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1225         spin_unlock_bh(&session->lock);
1226
1227         /*
1228          * clean up task if aborted. we have the xmitmutex so grab
1229          * the recv lock as a writer
1230          */
1231         write_lock_bh(conn->recv_lock);
1232         spin_lock(&session->lock);
1233         fail_command(conn, ctask, DID_ABORT << 16);
1234         spin_unlock(&session->lock);
1235         write_unlock_bh(conn->recv_lock);
1236
1237 success_rel_mutex:
1238         mutex_unlock(&conn->xmitmutex);
1239         return SUCCESS;
1240
1241 failed:
1242         spin_unlock_bh(&session->lock);
1243         mutex_unlock(&conn->xmitmutex);
1244
1245         debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1246         return FAILED;
1247 }
1248 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1249
1250 int
1251 iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
1252 {
1253         int i;
1254
1255         *items = kmalloc(max * sizeof(void*), GFP_KERNEL);
1256         if (*items == NULL)
1257                 return -ENOMEM;
1258
1259         q->max = max;
1260         q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
1261         if (q->pool == NULL) {
1262                 kfree(*items);
1263                 return -ENOMEM;
1264         }
1265
1266         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1267                               GFP_KERNEL, NULL);
1268         if (q->queue == ERR_PTR(-ENOMEM)) {
1269                 kfree(q->pool);
1270                 kfree(*items);
1271                 return -ENOMEM;
1272         }
1273
1274         for (i = 0; i < max; i++) {
1275                 q->pool[i] = kmalloc(item_size, GFP_KERNEL);
1276                 if (q->pool[i] == NULL) {
1277                         int j;
1278
1279                         for (j = 0; j < i; j++)
1280                                 kfree(q->pool[j]);
1281
1282                         kfifo_free(q->queue);
1283                         kfree(q->pool);
1284                         kfree(*items);
1285                         return -ENOMEM;
1286                 }
1287                 memset(q->pool[i], 0, item_size);
1288                 (*items)[i] = q->pool[i];
1289                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1290         }
1291         return 0;
1292 }
1293 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1294
1295 void iscsi_pool_free(struct iscsi_queue *q, void **items)
1296 {
1297         int i;
1298
1299         for (i = 0; i < q->max; i++)
1300                 kfree(items[i]);
1301         kfree(q->pool);
1302         kfree(items);
1303 }
1304 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1305
1306 /*
1307  * iSCSI Session's hostdata organization:
1308  *
1309  *    *------------------* <== hostdata_session(host->hostdata)
1310  *    | ptr to class sess|
1311  *    |------------------| <== iscsi_hostdata(host->hostdata)
1312  *    | iscsi_session    |
1313  *    *------------------*
1314  */
1315
1316 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1317                                  _sz % sizeof(unsigned long))
1318
1319 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1320
1321 /**
1322  * iscsi_session_setup - create iscsi cls session and host and session
1323  * @scsit: scsi transport template
1324  * @iscsit: iscsi transport template
1325  * @initial_cmdsn: initial CmdSN
1326  * @hostno: host no allocated
1327  *
1328  * This can be used by software iscsi_transports that allocate
1329  * a session per scsi host.
1330  **/
1331 struct iscsi_cls_session *
1332 iscsi_session_setup(struct iscsi_transport *iscsit,
1333                     struct scsi_transport_template *scsit,
1334                     int cmd_task_size, int mgmt_task_size,
1335                     uint32_t initial_cmdsn, uint32_t *hostno)
1336 {
1337         struct Scsi_Host *shost;
1338         struct iscsi_session *session;
1339         struct iscsi_cls_session *cls_session;
1340         int cmd_i;
1341
1342         shost = scsi_host_alloc(iscsit->host_template,
1343                                 hostdata_privsize(sizeof(*session)));
1344         if (!shost)
1345                 return NULL;
1346
1347         shost->max_id = 1;
1348         shost->max_channel = 0;
1349         shost->max_lun = iscsit->max_lun;
1350         shost->max_cmd_len = iscsit->max_cmd_len;
1351         shost->transportt = scsit;
1352         shost->transportt->create_work_queue = 1;
1353         *hostno = shost->host_no;
1354
1355         session = iscsi_hostdata(shost->hostdata);
1356         memset(session, 0, sizeof(struct iscsi_session));
1357         session->host = shost;
1358         session->state = ISCSI_STATE_FREE;
1359         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1360         session->cmds_max = ISCSI_XMIT_CMDS_MAX;
1361         session->cmdsn = initial_cmdsn;
1362         session->exp_cmdsn = initial_cmdsn + 1;
1363         session->max_cmdsn = initial_cmdsn + 1;
1364         session->max_r2t = 1;
1365         session->tt = iscsit;
1366
1367         /* initialize SCSI PDU commands pool */
1368         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1369                             (void***)&session->cmds,
1370                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1371                 goto cmdpool_alloc_fail;
1372
1373         /* pre-format cmds pool with ITT */
1374         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1375                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1376
1377                 if (cmd_task_size)
1378                         ctask->dd_data = &ctask[1];
1379                 ctask->itt = cmd_i;
1380                 INIT_LIST_HEAD(&ctask->running);
1381         }
1382
1383         spin_lock_init(&session->lock);
1384
1385         /* initialize immediate command pool */
1386         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1387                            (void***)&session->mgmt_cmds,
1388                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1389                 goto mgmtpool_alloc_fail;
1390
1391
1392         /* pre-format immediate cmds pool with ITT */
1393         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1394                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1395
1396                 if (mgmt_task_size)
1397                         mtask->dd_data = &mtask[1];
1398                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1399                 INIT_LIST_HEAD(&mtask->running);
1400         }
1401
1402         if (scsi_add_host(shost, NULL))
1403                 goto add_host_fail;
1404
1405         if (!try_module_get(iscsit->owner))
1406                 goto cls_session_fail;
1407
1408         cls_session = iscsi_create_session(shost, iscsit, 0);
1409         if (!cls_session)
1410                 goto module_put;
1411         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1412
1413         return cls_session;
1414
1415 module_put:
1416         module_put(iscsit->owner);
1417 cls_session_fail:
1418         scsi_remove_host(shost);
1419 add_host_fail:
1420         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1421 mgmtpool_alloc_fail:
1422         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1423 cmdpool_alloc_fail:
1424         scsi_host_put(shost);
1425         return NULL;
1426 }
1427 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1428
1429 /**
1430  * iscsi_session_teardown - destroy session, host, and cls_session
1431  * shost: scsi host
1432  *
1433  * This can be used by software iscsi_transports that allocate
1434  * a session per scsi host.
1435  **/
1436 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1437 {
1438         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1439         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1440         struct module *owner = cls_session->transport->owner;
1441
1442         scsi_remove_host(shost);
1443
1444         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1445         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1446
1447         kfree(session->targetname);
1448
1449         iscsi_destroy_session(cls_session);
1450         scsi_host_put(shost);
1451         module_put(owner);
1452 }
1453 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1454
1455 /**
1456  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1457  * @cls_session: iscsi_cls_session
1458  * @conn_idx: cid
1459  **/
1460 struct iscsi_cls_conn *
1461 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1462 {
1463         struct iscsi_session *session = class_to_transport_session(cls_session);
1464         struct iscsi_conn *conn;
1465         struct iscsi_cls_conn *cls_conn;
1466         char *data;
1467
1468         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1469         if (!cls_conn)
1470                 return NULL;
1471         conn = cls_conn->dd_data;
1472         memset(conn, 0, sizeof(*conn));
1473
1474         conn->session = session;
1475         conn->cls_conn = cls_conn;
1476         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1477         conn->id = conn_idx;
1478         conn->exp_statsn = 0;
1479         conn->tmabort_state = TMABORT_INITIAL;
1480         INIT_LIST_HEAD(&conn->run_list);
1481         INIT_LIST_HEAD(&conn->mgmt_run_list);
1482         INIT_LIST_HEAD(&conn->xmitqueue);
1483
1484         /* initialize general immediate & non-immediate PDU commands queue */
1485         conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1486                                         GFP_KERNEL, NULL);
1487         if (conn->immqueue == ERR_PTR(-ENOMEM))
1488                 goto immqueue_alloc_fail;
1489
1490         conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1491                                         GFP_KERNEL, NULL);
1492         if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
1493                 goto mgmtqueue_alloc_fail;
1494
1495         INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
1496
1497         /* allocate login_mtask used for the login/text sequences */
1498         spin_lock_bh(&session->lock);
1499         if (!__kfifo_get(session->mgmtpool.queue,
1500                          (void*)&conn->login_mtask,
1501                          sizeof(void*))) {
1502                 spin_unlock_bh(&session->lock);
1503                 goto login_mtask_alloc_fail;
1504         }
1505         spin_unlock_bh(&session->lock);
1506
1507         data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
1508         if (!data)
1509                 goto login_mtask_data_alloc_fail;
1510         conn->login_mtask->data = conn->data = data;
1511
1512         init_timer(&conn->tmabort_timer);
1513         mutex_init(&conn->xmitmutex);
1514         init_waitqueue_head(&conn->ehwait);
1515
1516         return cls_conn;
1517
1518 login_mtask_data_alloc_fail:
1519         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1520                     sizeof(void*));
1521 login_mtask_alloc_fail:
1522         kfifo_free(conn->mgmtqueue);
1523 mgmtqueue_alloc_fail:
1524         kfifo_free(conn->immqueue);
1525 immqueue_alloc_fail:
1526         iscsi_destroy_conn(cls_conn);
1527         return NULL;
1528 }
1529 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1530
1531 /**
1532  * iscsi_conn_teardown - teardown iscsi connection
1533  * cls_conn: iscsi class connection
1534  *
1535  * TODO: we may need to make this into a two step process
1536  * like scsi-mls remove + put host
1537  */
1538 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1539 {
1540         struct iscsi_conn *conn = cls_conn->dd_data;
1541         struct iscsi_session *session = conn->session;
1542         unsigned long flags;
1543
1544         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1545         mutex_lock(&conn->xmitmutex);
1546
1547         spin_lock_bh(&session->lock);
1548         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1549         if (session->leadconn == conn) {
1550                 /*
1551                  * leading connection? then give up on recovery.
1552                  */
1553                 session->state = ISCSI_STATE_TERMINATE;
1554                 wake_up(&conn->ehwait);
1555         }
1556         spin_unlock_bh(&session->lock);
1557
1558         mutex_unlock(&conn->xmitmutex);
1559
1560         /*
1561          * Block until all in-progress commands for this connection
1562          * time out or fail.
1563          */
1564         for (;;) {
1565                 spin_lock_irqsave(session->host->host_lock, flags);
1566                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1567                         spin_unlock_irqrestore(session->host->host_lock, flags);
1568                         break;
1569                 }
1570                 spin_unlock_irqrestore(session->host->host_lock, flags);
1571                 msleep_interruptible(500);
1572                 printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
1573                        "host_failed %d\n", session->host->host_busy,
1574                        session->host->host_failed);
1575                 /*
1576                  * force eh_abort() to unblock
1577                  */
1578                 wake_up(&conn->ehwait);
1579         }
1580
1581         spin_lock_bh(&session->lock);
1582         kfree(conn->data);
1583         kfree(conn->persistent_address);
1584         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1585                     sizeof(void*));
1586         if (session->leadconn == conn) {
1587                 session->leadconn = NULL;
1588                 /* no connections exits.. reset sequencing */
1589                 session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
1590         }
1591         spin_unlock_bh(&session->lock);
1592
1593         kfifo_free(conn->immqueue);
1594         kfifo_free(conn->mgmtqueue);
1595
1596         iscsi_destroy_conn(cls_conn);
1597 }
1598 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1599
1600 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1601 {
1602         struct iscsi_conn *conn = cls_conn->dd_data;
1603         struct iscsi_session *session = conn->session;
1604
1605         if (!session) {
1606                 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1607                 return -EPERM;
1608         }
1609
1610         if ((session->imm_data_en || !session->initial_r2t_en) &&
1611              session->first_burst > session->max_burst) {
1612                 printk("iscsi: invalid burst lengths: "
1613                        "first_burst %d max_burst %d\n",
1614                        session->first_burst, session->max_burst);
1615                 return -EINVAL;
1616         }
1617
1618         spin_lock_bh(&session->lock);
1619         conn->c_stage = ISCSI_CONN_STARTED;
1620         session->state = ISCSI_STATE_LOGGED_IN;
1621
1622         switch(conn->stop_stage) {
1623         case STOP_CONN_RECOVER:
1624                 /*
1625                  * unblock eh_abort() if it is blocked. re-try all
1626                  * commands after successful recovery
1627                  */
1628                 conn->stop_stage = 0;
1629                 conn->tmabort_state = TMABORT_INITIAL;
1630                 session->age++;
1631                 spin_unlock_bh(&session->lock);
1632
1633                 iscsi_unblock_session(session_to_cls(session));
1634                 wake_up(&conn->ehwait);
1635                 return 0;
1636         case STOP_CONN_TERM:
1637                 conn->stop_stage = 0;
1638                 break;
1639         default:
1640                 break;
1641         }
1642         spin_unlock_bh(&session->lock);
1643
1644         return 0;
1645 }
1646 EXPORT_SYMBOL_GPL(iscsi_conn_start);
1647
1648 static void
1649 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
1650 {
1651         struct iscsi_mgmt_task *mtask, *tmp;
1652
1653         /* handle pending */
1654         while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
1655                __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
1656                 if (mtask == conn->login_mtask)
1657                         continue;
1658                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
1659                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1660                             sizeof(void*));
1661         }
1662
1663         /* handle running */
1664         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
1665                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
1666                 list_del(&mtask->running);
1667
1668                 if (mtask == conn->login_mtask)
1669                         continue;
1670                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1671                            sizeof(void*));
1672         }
1673
1674         conn->mtask = NULL;
1675 }
1676
1677 /* Fail commands. Mutex and session lock held and recv side suspended */
1678 static void fail_all_commands(struct iscsi_conn *conn)
1679 {
1680         struct iscsi_cmd_task *ctask, *tmp;
1681
1682         /* flush pending */
1683         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1684                 debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
1685                            ctask->itt);
1686                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1687         }
1688
1689         /* fail all other running */
1690         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1691                 debug_scsi("failing in progress sc %p itt 0x%x\n",
1692                            ctask->sc, ctask->itt);
1693                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1694         }
1695
1696         conn->ctask = NULL;
1697 }
1698
1699 static void iscsi_start_session_recovery(struct iscsi_session *session,
1700                                          struct iscsi_conn *conn, int flag)
1701 {
1702         int old_stop_stage;
1703
1704         spin_lock_bh(&session->lock);
1705         if (conn->stop_stage == STOP_CONN_TERM) {
1706                 spin_unlock_bh(&session->lock);
1707                 return;
1708         }
1709
1710         /*
1711          * When this is called for the in_login state, we only want to clean
1712          * up the login task and connection. We do not need to block and set
1713          * the recovery state again
1714          */
1715         if (flag == STOP_CONN_TERM)
1716                 session->state = ISCSI_STATE_TERMINATE;
1717         else if (conn->stop_stage != STOP_CONN_RECOVER)
1718                 session->state = ISCSI_STATE_IN_RECOVERY;
1719
1720         old_stop_stage = conn->stop_stage;
1721         conn->stop_stage = flag;
1722         conn->c_stage = ISCSI_CONN_STOPPED;
1723         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1724         spin_unlock_bh(&session->lock);
1725
1726         write_lock_bh(conn->recv_lock);
1727         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1728         write_unlock_bh(conn->recv_lock);
1729
1730         mutex_lock(&conn->xmitmutex);
1731         /*
1732          * for connection level recovery we should not calculate
1733          * header digest. conn->hdr_size used for optimization
1734          * in hdr_extract() and will be re-negotiated at
1735          * set_param() time.
1736          */
1737         if (flag == STOP_CONN_RECOVER) {
1738                 conn->hdrdgst_en = 0;
1739                 conn->datadgst_en = 0;
1740                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
1741                     old_stop_stage != STOP_CONN_RECOVER) {
1742                         debug_scsi("blocking session\n");
1743                         iscsi_block_session(session_to_cls(session));
1744                 }
1745         }
1746
1747         /*
1748          * flush queues.
1749          */
1750         spin_lock_bh(&session->lock);
1751         fail_all_commands(conn);
1752         flush_control_queues(session, conn);
1753         spin_unlock_bh(&session->lock);
1754
1755         mutex_unlock(&conn->xmitmutex);
1756 }
1757
1758 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1759 {
1760         struct iscsi_conn *conn = cls_conn->dd_data;
1761         struct iscsi_session *session = conn->session;
1762
1763         switch (flag) {
1764         case STOP_CONN_RECOVER:
1765         case STOP_CONN_TERM:
1766                 iscsi_start_session_recovery(session, conn, flag);
1767                 break;
1768         default:
1769                 printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
1770         }
1771 }
1772 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
1773
1774 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
1775                     struct iscsi_cls_conn *cls_conn, int is_leading)
1776 {
1777         struct iscsi_session *session = class_to_transport_session(cls_session);
1778         struct iscsi_conn *conn = cls_conn->dd_data;
1779
1780         spin_lock_bh(&session->lock);
1781         if (is_leading)
1782                 session->leadconn = conn;
1783         spin_unlock_bh(&session->lock);
1784
1785         /*
1786          * Unblock xmitworker(), Login Phase will pass through.
1787          */
1788         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1789         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1790         return 0;
1791 }
1792 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
1793
1794
1795 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
1796                     enum iscsi_param param, char *buf, int buflen)
1797 {
1798         struct iscsi_conn *conn = cls_conn->dd_data;
1799         struct iscsi_session *session = conn->session;
1800         uint32_t value;
1801
1802         switch(param) {
1803         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1804                 sscanf(buf, "%d", &conn->max_recv_dlength);
1805                 break;
1806         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1807                 sscanf(buf, "%d", &conn->max_xmit_dlength);
1808                 break;
1809         case ISCSI_PARAM_HDRDGST_EN:
1810                 sscanf(buf, "%d", &conn->hdrdgst_en);
1811                 break;
1812         case ISCSI_PARAM_DATADGST_EN:
1813                 sscanf(buf, "%d", &conn->datadgst_en);
1814                 break;
1815         case ISCSI_PARAM_INITIAL_R2T_EN:
1816                 sscanf(buf, "%d", &session->initial_r2t_en);
1817                 break;
1818         case ISCSI_PARAM_MAX_R2T:
1819                 sscanf(buf, "%d", &session->max_r2t);
1820                 break;
1821         case ISCSI_PARAM_IMM_DATA_EN:
1822                 sscanf(buf, "%d", &session->imm_data_en);
1823                 break;
1824         case ISCSI_PARAM_FIRST_BURST:
1825                 sscanf(buf, "%d", &session->first_burst);
1826                 break;
1827         case ISCSI_PARAM_MAX_BURST:
1828                 sscanf(buf, "%d", &session->max_burst);
1829                 break;
1830         case ISCSI_PARAM_PDU_INORDER_EN:
1831                 sscanf(buf, "%d", &session->pdu_inorder_en);
1832                 break;
1833         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1834                 sscanf(buf, "%d", &session->dataseq_inorder_en);
1835                 break;
1836         case ISCSI_PARAM_ERL:
1837                 sscanf(buf, "%d", &session->erl);
1838                 break;
1839         case ISCSI_PARAM_IFMARKER_EN:
1840                 sscanf(buf, "%d", &value);
1841                 BUG_ON(value);
1842                 break;
1843         case ISCSI_PARAM_OFMARKER_EN:
1844                 sscanf(buf, "%d", &value);
1845                 BUG_ON(value);
1846                 break;
1847         case ISCSI_PARAM_EXP_STATSN:
1848                 sscanf(buf, "%u", &conn->exp_statsn);
1849                 break;
1850         case ISCSI_PARAM_TARGET_NAME:
1851                 /* this should not change between logins */
1852                 if (session->targetname)
1853                         break;
1854
1855                 session->targetname = kstrdup(buf, GFP_KERNEL);
1856                 if (!session->targetname)
1857                         return -ENOMEM;
1858                 break;
1859         case ISCSI_PARAM_TPGT:
1860                 sscanf(buf, "%d", &session->tpgt);
1861                 break;
1862         case ISCSI_PARAM_PERSISTENT_PORT:
1863                 sscanf(buf, "%d", &conn->persistent_port);
1864                 break;
1865         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1866                 /*
1867                  * this is the address returned in discovery so it should
1868                  * not change between logins.
1869                  */
1870                 if (conn->persistent_address)
1871                         break;
1872
1873                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
1874                 if (!conn->persistent_address)
1875                         return -ENOMEM;
1876                 break;
1877         default:
1878                 return -ENOSYS;
1879         }
1880
1881         return 0;
1882 }
1883 EXPORT_SYMBOL_GPL(iscsi_set_param);
1884
1885 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
1886                             enum iscsi_param param, char *buf)
1887 {
1888         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1889         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1890         int len;
1891
1892         switch(param) {
1893         case ISCSI_PARAM_INITIAL_R2T_EN:
1894                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
1895                 break;
1896         case ISCSI_PARAM_MAX_R2T:
1897                 len = sprintf(buf, "%hu\n", session->max_r2t);
1898                 break;
1899         case ISCSI_PARAM_IMM_DATA_EN:
1900                 len = sprintf(buf, "%d\n", session->imm_data_en);
1901                 break;
1902         case ISCSI_PARAM_FIRST_BURST:
1903                 len = sprintf(buf, "%u\n", session->first_burst);
1904                 break;
1905         case ISCSI_PARAM_MAX_BURST:
1906                 len = sprintf(buf, "%u\n", session->max_burst);
1907                 break;
1908         case ISCSI_PARAM_PDU_INORDER_EN:
1909                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
1910                 break;
1911         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1912                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
1913                 break;
1914         case ISCSI_PARAM_ERL:
1915                 len = sprintf(buf, "%d\n", session->erl);
1916                 break;
1917         case ISCSI_PARAM_TARGET_NAME:
1918                 len = sprintf(buf, "%s\n", session->targetname);
1919                 break;
1920         case ISCSI_PARAM_TPGT:
1921                 len = sprintf(buf, "%d\n", session->tpgt);
1922                 break;
1923         default:
1924                 return -ENOSYS;
1925         }
1926
1927         return len;
1928 }
1929 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
1930
1931 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
1932                          enum iscsi_param param, char *buf)
1933 {
1934         struct iscsi_conn *conn = cls_conn->dd_data;
1935         int len;
1936
1937         switch(param) {
1938         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1939                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
1940                 break;
1941         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1942                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
1943                 break;
1944         case ISCSI_PARAM_HDRDGST_EN:
1945                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
1946                 break;
1947         case ISCSI_PARAM_DATADGST_EN:
1948                 len = sprintf(buf, "%d\n", conn->datadgst_en);
1949                 break;
1950         case ISCSI_PARAM_IFMARKER_EN:
1951                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
1952                 break;
1953         case ISCSI_PARAM_OFMARKER_EN:
1954                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
1955                 break;
1956         case ISCSI_PARAM_EXP_STATSN:
1957                 len = sprintf(buf, "%u\n", conn->exp_statsn);
1958                 break;
1959         case ISCSI_PARAM_PERSISTENT_PORT:
1960                 len = sprintf(buf, "%d\n", conn->persistent_port);
1961                 break;
1962         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1963                 len = sprintf(buf, "%s\n", conn->persistent_address);
1964                 break;
1965         default:
1966                 return -ENOSYS;
1967         }
1968
1969         return len;
1970 }
1971 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
1972
1973 MODULE_AUTHOR("Mike Christie");
1974 MODULE_DESCRIPTION("iSCSI library functions");
1975 MODULE_LICENSE("GPL");