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         /* 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
 665                 spin_lock_bh(&conn->session->lock);
 666                 __iscsi_put_ctask(conn->ctask);
 667                 if (rc) {
 668                         spin_unlock_bh(&conn->session->lock);
 669                         goto again;
 670                 }
 671         }
 672         spin_unlock_bh(&conn->session->lock);
 673         /* done with this ctask */
 674         conn->ctask = NULL;
 675
 676         /* process the rest control plane PDUs, if any */
 677         if (unlikely(__kfifo_len(conn->mgmtqueue))) {
 678                 while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
 679                                    sizeof(void*))) {
 680                         spin_lock_bh(&conn->session->lock);
 681                         list_add_tail(&conn->mtask->running,
 682                                       &conn->mgmt_run_list);
 683                         spin_unlock_bh(&conn->session->lock);
 684                         rc = tt->xmit_mgmt_task(conn, conn->mtask);
 685                         if (rc)
 686                                 goto again;
 687                 }
 688                 /* done with this mtask */
 689                 conn->mtask = NULL;
 690         }
 691
 692         return -ENODATA;
 693
 694 again:
 695         if (unlikely(conn->suspend_tx))
 696                 return -ENODATA;
 697
 698         return rc;
 699 }
 700
 701 static void iscsi_xmitworker(void *data)
 702 {
 703         struct iscsi_conn *conn = data;
 704         int rc;
 705         /*
 706          * serialize Xmit worker on a per-connection basis.
 707          */
 708         mutex_lock(&conn->xmitmutex);
 709         do {
 710                 rc = iscsi_data_xmit(conn);
 711         } while (rc >= 0 || rc == -EAGAIN);
 712         mutex_unlock(&conn->xmitmutex);
 713 }
 714
 715 enum {
 716         FAILURE_BAD_HOST = 1,
 717         FAILURE_SESSION_FAILED,
 718         FAILURE_SESSION_FREED,
 719         FAILURE_WINDOW_CLOSED,
 720         FAILURE_OOM,
 721         FAILURE_SESSION_TERMINATE,
 722         FAILURE_SESSION_IN_RECOVERY,
 723         FAILURE_SESSION_RECOVERY_TIMEOUT,
 724 };
 725
 726 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 727 {
 728         struct Scsi_Host *host;
 729         int reason = 0;
 730         struct iscsi_session *session;
 731         struct iscsi_conn *conn;
 732         struct iscsi_cmd_task *ctask = NULL;
 733
 734         sc->scsi_done = done;
 735         sc->result = 0;
 736         sc->SCp.ptr = NULL;
 737
 738         host = sc->device->host;
 739         session = iscsi_hostdata(host->hostdata);
 740
 741         spin_lock(&session->lock);
 742
 743         /*
 744          * ISCSI_STATE_FAILED is a temp. state. The recovery
 745          * code will decide what is best to do with command queued
 746          * during this time
 747          */
 748         if (session->state != ISCSI_STATE_LOGGED_IN &&
 749             session->state != ISCSI_STATE_FAILED) {
 750                 /*
 751                  * to handle the race between when we set the recovery state
 752                  * and block the session we requeue here (commands could
 753                  * be entering our queuecommand while a block is starting
 754                  * up because the block code is not locked)
 755                  */
 756                 if (session->state == ISCSI_STATE_IN_RECOVERY) {
 757                         reason = FAILURE_SESSION_IN_RECOVERY;
 758                         goto reject;
 759                 }
 760
 761                 if (session->state == ISCSI_STATE_RECOVERY_FAILED)
 762                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
 763                 else if (session->state == ISCSI_STATE_TERMINATE)
 764                         reason = FAILURE_SESSION_TERMINATE;
 765                 else
 766                         reason = FAILURE_SESSION_FREED;
 767                 goto fault;
 768         }
 769
 770         /*
 771          * Check for iSCSI window and take care of CmdSN wrap-around
 772          */
 773         if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
 774                 reason = FAILURE_WINDOW_CLOSED;
 775                 goto reject;
 776         }
 777
 778         conn = session->leadconn;
 779         if (!conn) {
 780                 reason = FAILURE_SESSION_FREED;
 781                 goto fault;
 782         }
 783
 784         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
 785                          sizeof(void*))) {
 786                 reason = FAILURE_OOM;
 787                 goto reject;
 788         }
 789         sc->SCp.phase = session->age;
 790         sc->SCp.ptr = (char *)ctask;
 791
 792         atomic_set(&ctask->refcount, 1);
 793         ctask->state = ISCSI_TASK_PENDING;
 794         ctask->mtask = NULL;
 795         ctask->conn = conn;
 796         ctask->sc = sc;
 797         INIT_LIST_HEAD(&ctask->running);
 798         ctask->total_length = sc->request_bufflen;
 799         iscsi_prep_scsi_cmd_pdu(ctask);
 800
 801         session->tt->init_cmd_task(ctask);
 802
 803         list_add_tail(&ctask->running, &conn->xmitqueue);
 804         debug_scsi(
 805                "ctask enq [%s cid %d sc %p cdb 0x%x itt 0x%x len %d cmdsn %d "
 806                 "win %d]\n",
 807                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
 808                 conn->id, sc, sc->cmnd[0], ctask->itt, sc->request_bufflen,
 809                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 810         spin_unlock(&session->lock);
 811
 812         scsi_queue_work(host, &conn->xmitwork);
 813         return 0;
 814
 815 reject:
 816         spin_unlock(&session->lock);
 817         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
 818         return SCSI_MLQUEUE_HOST_BUSY;
 819
 820 fault:
 821         spin_unlock(&session->lock);
 822         printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
 823                sc->cmnd[0], reason);
 824         sc->result = (DID_NO_CONNECT << 16);
 825         sc->resid = sc->request_bufflen;
 826         sc->scsi_done(sc);
 827         return 0;
 828 }
 829 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
 830
 831 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
 832 {
 833         if (depth > ISCSI_MAX_CMD_PER_LUN)
 834                 depth = ISCSI_MAX_CMD_PER_LUN;
 835         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 836         return sdev->queue_depth;
 837 }
 838 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
 839
 840 static int
 841 iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 842                         char *data, uint32_t data_size)
 843 {
 844         struct iscsi_session *session = conn->session;
 845         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 846         struct iscsi_mgmt_task *mtask;
 847
 848         spin_lock_bh(&session->lock);
 849         if (session->state == ISCSI_STATE_TERMINATE) {
 850                 spin_unlock_bh(&session->lock);
 851                 return -EPERM;
 852         }
 853         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
 854             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 855                 /*
 856                  * Login and Text are sent serially, in
 857                  * request-followed-by-response sequence.
 858                  * Same mtask can be used. Same ITT must be used.
 859                  * Note that login_mtask is preallocated at conn_create().
 860                  */
 861                 mtask = conn->login_mtask;
 862         else {
 863                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 864                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 865
 866                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 867                 if (!__kfifo_get(session->mgmtpool.queue,
 868                                  (void*)&mtask, sizeof(void*))) {
 869                         spin_unlock_bh(&session->lock);
 870                         return -ENOSPC;
 871                 }
 872         }
 873
 874         /*
 875          * pre-format CmdSN for outgoing PDU.
 876          */
 877         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
 878                 hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) |
 879                            (session->age << ISCSI_AGE_SHIFT);
 880                 nop->cmdsn = cpu_to_be32(session->cmdsn);
 881                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 882                     !(hdr->opcode & ISCSI_OP_IMMEDIATE))
 883                         session->cmdsn++;
 884         } else
 885                 /* do not advance CmdSN */
 886                 nop->cmdsn = cpu_to_be32(session->cmdsn);
 887
 888         if (data_size) {
 889                 memcpy(mtask->data, data, data_size);
 890                 mtask->data_count = data_size;
 891         } else
 892                 mtask->data_count = 0;
 893
 894         INIT_LIST_HEAD(&mtask->running);
 895         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
 896         if (session->tt->init_mgmt_task)
 897                 session->tt->init_mgmt_task(conn, mtask, data, data_size);
 898         spin_unlock_bh(&session->lock);
 899
 900         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 901                    hdr->opcode, hdr->itt, data_size);
 902
 903         /*
 904          * since send_pdu() could be called at least from two contexts,
 905          * we need to serialize __kfifo_put, so we don't have to take
 906          * additional lock on fast data-path
 907          */
 908         if (hdr->opcode & ISCSI_OP_IMMEDIATE)
 909                 __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
 910         else
 911                 __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
 912
 913         scsi_queue_work(session->host, &conn->xmitwork);
 914         return 0;
 915 }
 916
 917 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 918                         char *data, uint32_t data_size)
 919 {
 920         struct iscsi_conn *conn = cls_conn->dd_data;
 921         int rc;
 922
 923         mutex_lock(&conn->xmitmutex);
 924         rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
 925         mutex_unlock(&conn->xmitmutex);
 926
 927         return rc;
 928 }
 929 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 930
 931 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
 932 {
 933         struct iscsi_session *session = class_to_transport_session(cls_session);
 934         struct iscsi_conn *conn = session->leadconn;
 935
 936         spin_lock_bh(&session->lock);
 937         if (session->state != ISCSI_STATE_LOGGED_IN) {
 938                 session->state = ISCSI_STATE_RECOVERY_FAILED;
 939                 if (conn)
 940                         wake_up(&conn->ehwait);
 941         }
 942         spin_unlock_bh(&session->lock);
 943 }
 944 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
 945
 946 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
 947 {
 948         struct Scsi_Host *host = sc->device->host;
 949         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
 950         struct iscsi_conn *conn = session->leadconn;
 951         int fail_session = 0;
 952
 953         spin_lock_bh(&session->lock);
 954         if (session->state == ISCSI_STATE_TERMINATE) {
 955 failed:
 956                 debug_scsi("failing host reset: session terminated "
 957                            "[CID %d age %d]", conn->id, session->age);
 958                 spin_unlock_bh(&session->lock);
 959                 return FAILED;
 960         }
 961
 962         if (sc->SCp.phase == session->age) {
 963                 debug_scsi("failing connection CID %d due to SCSI host reset",
 964                            conn->id);
 965                 fail_session = 1;
 966         }
 967         spin_unlock_bh(&session->lock);
 968
 969         /*
 970          * we drop the lock here but the leadconn cannot be destoyed while
 971          * we are in the scsi eh
 972          */
 973         if (fail_session)
 974                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 975
 976         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
 977         wait_event_interruptible(conn->ehwait,
 978                                  session->state == ISCSI_STATE_TERMINATE ||
 979                                  session->state == ISCSI_STATE_LOGGED_IN ||
 980                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
 981         if (signal_pending(current))
 982                 flush_signals(current);
 983
 984         spin_lock_bh(&session->lock);
 985         if (session->state == ISCSI_STATE_LOGGED_IN)
 986                 printk(KERN_INFO "iscsi: host reset succeeded\n");
 987         else
 988                 goto failed;
 989         spin_unlock_bh(&session->lock);
 990
 991         return SUCCESS;
 992 }
 993 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
 994
 995 static void iscsi_tmabort_timedout(unsigned long data)
 996 {
 997         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
 998         struct iscsi_conn *conn = ctask->conn;
 999         struct iscsi_session *session = conn->session;
1000
1001         spin_lock(&session->lock);
1002         if (conn->tmabort_state == TMABORT_INITIAL) {
1003                 conn->tmabort_state = TMABORT_TIMEDOUT;
1004                 debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
1005                         ctask->sc, ctask->itt);
1006                 /* unblock eh_abort() */
1007                 wake_up(&conn->ehwait);
1008         }
1009         spin_unlock(&session->lock);
1010 }
1011
1012 /* must be called with the mutex lock */
1013 static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
1014                                  struct iscsi_cmd_task *ctask)
1015 {
1016         struct iscsi_conn *conn = ctask->conn;
1017         struct iscsi_session *session = conn->session;
1018         struct iscsi_tm *hdr = &conn->tmhdr;
1019         int rc;
1020
1021         /*
1022          * ctask timed out but session is OK requests must be serialized.
1023          */
1024         memset(hdr, 0, sizeof(struct iscsi_tm));
1025         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1026         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
1027         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1028         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1029         hdr->rtt = ctask->hdr->itt;
1030         hdr->refcmdsn = ctask->hdr->cmdsn;
1031
1032         rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
1033                                      NULL, 0);
1034         if (rc) {
1035                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1036                 debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc);
1037                 return rc;
1038         }
1039
1040         debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
1041
1042         spin_lock_bh(&session->lock);
1043         ctask->mtask = (struct iscsi_mgmt_task *)
1044                         session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) -
1045                                         ISCSI_MGMT_ITT_OFFSET];
1046
1047         if (conn->tmabort_state == TMABORT_INITIAL) {
1048                 conn->tmfcmd_pdus_cnt++;
1049                 conn->tmabort_timer.expires = 10*HZ + jiffies;
1050                 conn->tmabort_timer.function = iscsi_tmabort_timedout;
1051                 conn->tmabort_timer.data = (unsigned long)ctask;
1052                 add_timer(&conn->tmabort_timer);
1053                 debug_scsi("abort set timeout [itt 0x%x]", ctask->itt);
1054         }
1055         spin_unlock_bh(&session->lock);
1056         mutex_unlock(&conn->xmitmutex);
1057
1058         /*
1059          * block eh thread until:
1060          *
1061          * 1) abort response
1062          * 2) abort timeout
1063          * 3) session is terminated or restarted or userspace has
1064          * given up on recovery
1065          */
1066         wait_event_interruptible(conn->ehwait,
1067                                  sc->SCp.phase != session->age ||
1068                                  session->state != ISCSI_STATE_LOGGED_IN ||
1069                                  conn->tmabort_state != TMABORT_INITIAL);
1070         if (signal_pending(current))
1071                 flush_signals(current);
1072         del_timer_sync(&conn->tmabort_timer);
1073
1074         mutex_lock(&conn->xmitmutex);
1075         return 0;
1076 }
1077
1078 /*
1079  * xmit mutex and session lock must be held
1080  */
1081 static struct iscsi_mgmt_task *
1082 iscsi_remove_mgmt_task(struct kfifo *fifo, uint32_t itt)
1083 {
1084         int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);
1085         struct iscsi_mgmt_task *task;
1086
1087         debug_scsi("searching %d tasks\n", nr_tasks);
1088
1089         for (i = 0; i < nr_tasks; i++) {
1090                 __kfifo_get(fifo, (void*)&task, sizeof(void*));
1091                 debug_scsi("check task %u\n", task->itt);
1092
1093                 if (task->itt == itt) {
1094                         debug_scsi("matched task\n");
1095                         return task;
1096                 }
1097
1098                 __kfifo_put(fifo, (void*)&task, sizeof(void*));
1099         }
1100         return NULL;
1101 }
1102
1103 static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
1104 {
1105         struct iscsi_conn *conn = ctask->conn;
1106         struct iscsi_session *session = conn->session;
1107
1108         if (!ctask->mtask)
1109                 return -EINVAL;
1110
1111         if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
1112                 list_del(&ctask->mtask->running);
1113         __kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
1114                     sizeof(void*));
1115         ctask->mtask = NULL;
1116         return 0;
1117 }
1118
1119 /*
1120  * session lock and xmitmutex must be held
1121  */
1122 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1123                          int err)
1124 {
1125         struct scsi_cmnd *sc;
1126
1127         sc = ctask->sc;
1128         if (!sc)
1129                 return;
1130
1131         conn->session->tt->cleanup_cmd_task(conn, ctask);
1132         iscsi_ctask_mtask_cleanup(ctask);
1133
1134         sc->result = err;
1135         sc->resid = sc->request_bufflen;
1136         /* release ref from queuecommand */
1137         __iscsi_put_ctask(ctask);
1138 }
1139
1140 int iscsi_eh_abort(struct scsi_cmnd *sc)
1141 {
1142         struct iscsi_cmd_task *ctask;
1143         struct iscsi_conn *conn;
1144         struct iscsi_session *session;
1145         int rc;
1146
1147         /*
1148          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1149          * got the command.
1150          */
1151         if (!sc->SCp.ptr) {
1152                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1153                 return SUCCESS;
1154         }
1155
1156         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1157         conn = ctask->conn;
1158         session = conn->session;
1159
1160         conn->eh_abort_cnt++;
1161         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1162
1163         mutex_lock(&conn->xmitmutex);
1164         spin_lock_bh(&session->lock);
1165
1166         /*
1167          * If we are not logged in or we have started a new session
1168          * then let the host reset code handle this
1169          */
1170         if (session->state != ISCSI_STATE_LOGGED_IN ||
1171             sc->SCp.phase != session->age)
1172                 goto failed;
1173
1174         /* ctask completed before time out */
1175         if (!ctask->sc) {
1176                 spin_unlock_bh(&session->lock);
1177                 debug_scsi("sc completed while abort in progress\n");
1178                 goto success_rel_mutex;
1179         }
1180
1181         /* what should we do here ? */
1182         if (conn->ctask == ctask) {
1183                 printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. "
1184                        "Failing abort\n", sc, ctask->itt);
1185                 goto failed;
1186         }
1187
1188         if (ctask->state == ISCSI_TASK_PENDING)
1189                 goto success_cleanup;
1190
1191         conn->tmabort_state = TMABORT_INITIAL;
1192
1193         spin_unlock_bh(&session->lock);
1194         rc = iscsi_exec_abort_task(sc, ctask);
1195         spin_lock_bh(&session->lock);
1196
1197         if (rc || sc->SCp.phase != session->age ||
1198             session->state != ISCSI_STATE_LOGGED_IN)
1199                 goto failed;
1200         iscsi_ctask_mtask_cleanup(ctask);
1201
1202         switch (conn->tmabort_state) {
1203         case TMABORT_SUCCESS:
1204                 goto success_cleanup;
1205         case TMABORT_NOT_FOUND:
1206                 if (!ctask->sc) {
1207                         /* ctask completed before tmf abort response */
1208                         spin_unlock_bh(&session->lock);
1209                         debug_scsi("sc completed while abort in progress\n");
1210                         goto success_rel_mutex;
1211                 }
1212                 /* fall through */
1213         default:
1214                 /* timedout or failed */
1215                 spin_unlock_bh(&session->lock);
1216                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1217                 spin_lock_bh(&session->lock);
1218                 goto failed;
1219         }
1220
1221 success_cleanup:
1222         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1223         spin_unlock_bh(&session->lock);
1224
1225         /*
1226          * clean up task if aborted. we have the xmitmutex so grab
1227          * the recv lock as a writer
1228          */
1229         write_lock_bh(conn->recv_lock);
1230         spin_lock(&session->lock);
1231         fail_command(conn, ctask, DID_ABORT << 16);
1232         spin_unlock(&session->lock);
1233         write_unlock_bh(conn->recv_lock);
1234
1235 success_rel_mutex:
1236         mutex_unlock(&conn->xmitmutex);
1237         return SUCCESS;
1238
1239 failed:
1240         spin_unlock_bh(&session->lock);
1241         mutex_unlock(&conn->xmitmutex);
1242
1243         debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1244         return FAILED;
1245 }
1246 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1247
1248 int
1249 iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
1250 {
1251         int i;
1252
1253         *items = kmalloc(max * sizeof(void*), GFP_KERNEL);
1254         if (*items == NULL)
1255                 return -ENOMEM;
1256
1257         q->max = max;
1258         q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
1259         if (q->pool == NULL) {
1260                 kfree(*items);
1261                 return -ENOMEM;
1262         }
1263
1264         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1265                               GFP_KERNEL, NULL);
1266         if (q->queue == ERR_PTR(-ENOMEM)) {
1267                 kfree(q->pool);
1268                 kfree(*items);
1269                 return -ENOMEM;
1270         }
1271
1272         for (i = 0; i < max; i++) {
1273                 q->pool[i] = kmalloc(item_size, GFP_KERNEL);
1274                 if (q->pool[i] == NULL) {
1275                         int j;
1276
1277                         for (j = 0; j < i; j++)
1278                                 kfree(q->pool[j]);
1279
1280                         kfifo_free(q->queue);
1281                         kfree(q->pool);
1282                         kfree(*items);
1283                         return -ENOMEM;
1284                 }
1285                 memset(q->pool[i], 0, item_size);
1286                 (*items)[i] = q->pool[i];
1287                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1288         }
1289         return 0;
1290 }
1291 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1292
1293 void iscsi_pool_free(struct iscsi_queue *q, void **items)
1294 {
1295         int i;
1296
1297         for (i = 0; i < q->max; i++)
1298                 kfree(items[i]);
1299         kfree(q->pool);
1300         kfree(items);
1301 }
1302 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1303
1304 /*
1305  * iSCSI Session's hostdata organization:
1306  *
1307  *    *------------------* <== hostdata_session(host->hostdata)
1308  *    | ptr to class sess|
1309  *    |------------------| <== iscsi_hostdata(host->hostdata)
1310  *    | iscsi_session    |
1311  *    *------------------*
1312  */
1313
1314 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1315                                  _sz % sizeof(unsigned long))
1316
1317 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1318
1319 /**
1320  * iscsi_session_setup - create iscsi cls session and host and session
1321  * @scsit: scsi transport template
1322  * @iscsit: iscsi transport template
1323  * @initial_cmdsn: initial CmdSN
1324  * @hostno: host no allocated
1325  *
1326  * This can be used by software iscsi_transports that allocate
1327  * a session per scsi host.
1328  **/
1329 struct iscsi_cls_session *
1330 iscsi_session_setup(struct iscsi_transport *iscsit,
1331                     struct scsi_transport_template *scsit,
1332                     int cmd_task_size, int mgmt_task_size,
1333                     uint32_t initial_cmdsn, uint32_t *hostno)
1334 {
1335         struct Scsi_Host *shost;
1336         struct iscsi_session *session;
1337         struct iscsi_cls_session *cls_session;
1338         int cmd_i;
1339
1340         shost = scsi_host_alloc(iscsit->host_template,
1341                                 hostdata_privsize(sizeof(*session)));
1342         if (!shost)
1343                 return NULL;
1344
1345         shost->max_id = 1;
1346         shost->max_channel = 0;
1347         shost->max_lun = iscsit->max_lun;
1348         shost->max_cmd_len = iscsit->max_cmd_len;
1349         shost->transportt = scsit;
1350         shost->transportt->create_work_queue = 1;
1351         *hostno = shost->host_no;
1352
1353         session = iscsi_hostdata(shost->hostdata);
1354         memset(session, 0, sizeof(struct iscsi_session));
1355         session->host = shost;
1356         session->state = ISCSI_STATE_FREE;
1357         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1358         session->cmds_max = ISCSI_XMIT_CMDS_MAX;
1359         session->cmdsn = initial_cmdsn;
1360         session->exp_cmdsn = initial_cmdsn + 1;
1361         session->max_cmdsn = initial_cmdsn + 1;
1362         session->max_r2t = 1;
1363         session->tt = iscsit;
1364
1365         /* initialize SCSI PDU commands pool */
1366         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1367                             (void***)&session->cmds,
1368                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1369                 goto cmdpool_alloc_fail;
1370
1371         /* pre-format cmds pool with ITT */
1372         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1373                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1374
1375                 if (cmd_task_size)
1376                         ctask->dd_data = &ctask[1];
1377                 ctask->itt = cmd_i;
1378                 INIT_LIST_HEAD(&ctask->running);
1379         }
1380
1381         spin_lock_init(&session->lock);
1382
1383         /* initialize immediate command pool */
1384         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1385                            (void***)&session->mgmt_cmds,
1386                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1387                 goto mgmtpool_alloc_fail;
1388
1389
1390         /* pre-format immediate cmds pool with ITT */
1391         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1392                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1393
1394                 if (mgmt_task_size)
1395                         mtask->dd_data = &mtask[1];
1396                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1397                 INIT_LIST_HEAD(&mtask->running);
1398         }
1399
1400         if (scsi_add_host(shost, NULL))
1401                 goto add_host_fail;
1402
1403         if (!try_module_get(iscsit->owner))
1404                 goto cls_session_fail;
1405
1406         cls_session = iscsi_create_session(shost, iscsit, 0);
1407         if (!cls_session)
1408                 goto module_put;
1409         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1410
1411         return cls_session;
1412
1413 module_put:
1414         module_put(iscsit->owner);
1415 cls_session_fail:
1416         scsi_remove_host(shost);
1417 add_host_fail:
1418         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1419 mgmtpool_alloc_fail:
1420         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1421 cmdpool_alloc_fail:
1422         scsi_host_put(shost);
1423         return NULL;
1424 }
1425 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1426
1427 /**
1428  * iscsi_session_teardown - destroy session, host, and cls_session
1429  * shost: scsi host
1430  *
1431  * This can be used by software iscsi_transports that allocate
1432  * a session per scsi host.
1433  **/
1434 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1435 {
1436         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1437         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1438         struct module *owner = cls_session->transport->owner;
1439
1440         scsi_remove_host(shost);
1441
1442         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1443         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1444
1445         kfree(session->targetname);
1446
1447         iscsi_destroy_session(cls_session);
1448         scsi_host_put(shost);
1449         module_put(owner);
1450 }
1451 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1452
1453 /**
1454  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1455  * @cls_session: iscsi_cls_session
1456  * @conn_idx: cid
1457  **/
1458 struct iscsi_cls_conn *
1459 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1460 {
1461         struct iscsi_session *session = class_to_transport_session(cls_session);
1462         struct iscsi_conn *conn;
1463         struct iscsi_cls_conn *cls_conn;
1464         char *data;
1465
1466         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1467         if (!cls_conn)
1468                 return NULL;
1469         conn = cls_conn->dd_data;
1470         memset(conn, 0, sizeof(*conn));
1471
1472         conn->session = session;
1473         conn->cls_conn = cls_conn;
1474         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1475         conn->id = conn_idx;
1476         conn->exp_statsn = 0;
1477         conn->tmabort_state = TMABORT_INITIAL;
1478         INIT_LIST_HEAD(&conn->run_list);
1479         INIT_LIST_HEAD(&conn->mgmt_run_list);
1480         INIT_LIST_HEAD(&conn->xmitqueue);
1481
1482         /* initialize general immediate & non-immediate PDU commands queue */
1483         conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1484                                         GFP_KERNEL, NULL);
1485         if (conn->immqueue == ERR_PTR(-ENOMEM))
1486                 goto immqueue_alloc_fail;
1487
1488         conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1489                                         GFP_KERNEL, NULL);
1490         if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
1491                 goto mgmtqueue_alloc_fail;
1492
1493         INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
1494
1495         /* allocate login_mtask used for the login/text sequences */
1496         spin_lock_bh(&session->lock);
1497         if (!__kfifo_get(session->mgmtpool.queue,
1498                          (void*)&conn->login_mtask,
1499                          sizeof(void*))) {
1500                 spin_unlock_bh(&session->lock);
1501                 goto login_mtask_alloc_fail;
1502         }
1503         spin_unlock_bh(&session->lock);
1504
1505         data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
1506         if (!data)
1507                 goto login_mtask_data_alloc_fail;
1508         conn->login_mtask->data = conn->data = data;
1509
1510         init_timer(&conn->tmabort_timer);
1511         mutex_init(&conn->xmitmutex);
1512         init_waitqueue_head(&conn->ehwait);
1513
1514         return cls_conn;
1515
1516 login_mtask_data_alloc_fail:
1517         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1518                     sizeof(void*));
1519 login_mtask_alloc_fail:
1520         kfifo_free(conn->mgmtqueue);
1521 mgmtqueue_alloc_fail:
1522         kfifo_free(conn->immqueue);
1523 immqueue_alloc_fail:
1524         iscsi_destroy_conn(cls_conn);
1525         return NULL;
1526 }
1527 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1528
1529 /**
1530  * iscsi_conn_teardown - teardown iscsi connection
1531  * cls_conn: iscsi class connection
1532  *
1533  * TODO: we may need to make this into a two step process
1534  * like scsi-mls remove + put host
1535  */
1536 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1537 {
1538         struct iscsi_conn *conn = cls_conn->dd_data;
1539         struct iscsi_session *session = conn->session;
1540         unsigned long flags;
1541
1542         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1543         mutex_lock(&conn->xmitmutex);
1544
1545         spin_lock_bh(&session->lock);
1546         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1547         if (session->leadconn == conn) {
1548                 /*
1549                  * leading connection? then give up on recovery.
1550                  */
1551                 session->state = ISCSI_STATE_TERMINATE;
1552                 wake_up(&conn->ehwait);
1553         }
1554         spin_unlock_bh(&session->lock);
1555
1556         mutex_unlock(&conn->xmitmutex);
1557
1558         /*
1559          * Block until all in-progress commands for this connection
1560          * time out or fail.
1561          */
1562         for (;;) {
1563                 spin_lock_irqsave(session->host->host_lock, flags);
1564                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1565                         spin_unlock_irqrestore(session->host->host_lock, flags);
1566                         break;
1567                 }
1568                 spin_unlock_irqrestore(session->host->host_lock, flags);
1569                 msleep_interruptible(500);
1570                 printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
1571                        "host_failed %d\n", session->host->host_busy,
1572                        session->host->host_failed);
1573                 /*
1574                  * force eh_abort() to unblock
1575                  */
1576                 wake_up(&conn->ehwait);
1577         }
1578
1579         spin_lock_bh(&session->lock);
1580         kfree(conn->data);
1581         kfree(conn->persistent_address);
1582         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1583                     sizeof(void*));
1584         if (session->leadconn == conn) {
1585                 session->leadconn = NULL;
1586                 /* no connections exits.. reset sequencing */
1587                 session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
1588         }
1589         spin_unlock_bh(&session->lock);
1590
1591         kfifo_free(conn->immqueue);
1592         kfifo_free(conn->mgmtqueue);
1593
1594         iscsi_destroy_conn(cls_conn);
1595 }
1596 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1597
1598 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1599 {
1600         struct iscsi_conn *conn = cls_conn->dd_data;
1601         struct iscsi_session *session = conn->session;
1602
1603         if (!session) {
1604                 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1605                 return -EPERM;
1606         }
1607
1608         if ((session->imm_data_en || !session->initial_r2t_en) &&
1609              session->first_burst > session->max_burst) {
1610                 printk("iscsi: invalid burst lengths: "
1611                        "first_burst %d max_burst %d\n",
1612                        session->first_burst, session->max_burst);
1613                 return -EINVAL;
1614         }
1615
1616         spin_lock_bh(&session->lock);
1617         conn->c_stage = ISCSI_CONN_STARTED;
1618         session->state = ISCSI_STATE_LOGGED_IN;
1619
1620         switch(conn->stop_stage) {
1621         case STOP_CONN_RECOVER:
1622                 /*
1623                  * unblock eh_abort() if it is blocked. re-try all
1624                  * commands after successful recovery
1625                  */
1626                 conn->stop_stage = 0;
1627                 conn->tmabort_state = TMABORT_INITIAL;
1628                 session->age++;
1629                 spin_unlock_bh(&session->lock);
1630
1631                 iscsi_unblock_session(session_to_cls(session));
1632                 wake_up(&conn->ehwait);
1633                 return 0;
1634         case STOP_CONN_TERM:
1635                 conn->stop_stage = 0;
1636                 break;
1637         default:
1638                 break;
1639         }
1640         spin_unlock_bh(&session->lock);
1641
1642         return 0;
1643 }
1644 EXPORT_SYMBOL_GPL(iscsi_conn_start);
1645
1646 static void
1647 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
1648 {
1649         struct iscsi_mgmt_task *mtask, *tmp;
1650
1651         /* handle pending */
1652         while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
1653                __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
1654                 if (mtask == conn->login_mtask)
1655                         continue;
1656                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
1657                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1658                             sizeof(void*));
1659         }
1660
1661         /* handle running */
1662         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
1663                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
1664                 list_del(&mtask->running);
1665
1666                 if (mtask == conn->login_mtask)
1667                         continue;
1668                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1669                            sizeof(void*));
1670         }
1671
1672         conn->mtask = NULL;
1673 }
1674
1675 /* Fail commands. Mutex and session lock held and recv side suspended */
1676 static void fail_all_commands(struct iscsi_conn *conn)
1677 {
1678         struct iscsi_cmd_task *ctask, *tmp;
1679
1680         /* flush pending */
1681         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1682                 debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
1683                            ctask->itt);
1684                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1685         }
1686
1687         /* fail all other running */
1688         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1689                 debug_scsi("failing in progress sc %p itt 0x%x\n",
1690                            ctask->sc, ctask->itt);
1691                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1692         }
1693
1694         conn->ctask = NULL;
1695 }
1696
1697 static void iscsi_start_session_recovery(struct iscsi_session *session,
1698                                          struct iscsi_conn *conn, int flag)
1699 {
1700         int old_stop_stage;
1701
1702         spin_lock_bh(&session->lock);
1703         if (conn->stop_stage == STOP_CONN_TERM) {
1704                 spin_unlock_bh(&session->lock);
1705                 return;
1706         }
1707
1708         /*
1709          * When this is called for the in_login state, we only want to clean
1710          * up the login task and connection. We do not need to block and set
1711          * the recovery state again
1712          */
1713         if (flag == STOP_CONN_TERM)
1714                 session->state = ISCSI_STATE_TERMINATE;
1715         else if (conn->stop_stage != STOP_CONN_RECOVER)
1716                 session->state = ISCSI_STATE_IN_RECOVERY;
1717
1718         old_stop_stage = conn->stop_stage;
1719         conn->stop_stage = flag;
1720         conn->c_stage = ISCSI_CONN_STOPPED;
1721         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1722         spin_unlock_bh(&session->lock);
1723
1724         write_lock_bh(conn->recv_lock);
1725         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1726         write_unlock_bh(conn->recv_lock);
1727
1728         mutex_lock(&conn->xmitmutex);
1729         /*
1730          * for connection level recovery we should not calculate
1731          * header digest. conn->hdr_size used for optimization
1732          * in hdr_extract() and will be re-negotiated at
1733          * set_param() time.
1734          */
1735         if (flag == STOP_CONN_RECOVER) {
1736                 conn->hdrdgst_en = 0;
1737                 conn->datadgst_en = 0;
1738                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
1739                     old_stop_stage != STOP_CONN_RECOVER) {
1740                         debug_scsi("blocking session\n");
1741                         iscsi_block_session(session_to_cls(session));
1742                 }
1743         }
1744
1745         /*
1746          * flush queues.
1747          */
1748         spin_lock_bh(&session->lock);
1749         fail_all_commands(conn);
1750         flush_control_queues(session, conn);
1751         spin_unlock_bh(&session->lock);
1752
1753         mutex_unlock(&conn->xmitmutex);
1754 }
1755
1756 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1757 {
1758         struct iscsi_conn *conn = cls_conn->dd_data;
1759         struct iscsi_session *session = conn->session;
1760
1761         switch (flag) {
1762         case STOP_CONN_RECOVER:
1763         case STOP_CONN_TERM:
1764                 iscsi_start_session_recovery(session, conn, flag);
1765                 break;
1766         default:
1767                 printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
1768         }
1769 }
1770 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
1771
1772 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
1773                     struct iscsi_cls_conn *cls_conn, int is_leading)
1774 {
1775         struct iscsi_session *session = class_to_transport_session(cls_session);
1776         struct iscsi_conn *conn = cls_conn->dd_data;
1777
1778         spin_lock_bh(&session->lock);
1779         if (is_leading)
1780                 session->leadconn = conn;
1781         spin_unlock_bh(&session->lock);
1782
1783         /*
1784          * Unblock xmitworker(), Login Phase will pass through.
1785          */
1786         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1787         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1788         return 0;
1789 }
1790 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
1791
1792
1793 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
1794                     enum iscsi_param param, char *buf, int buflen)
1795 {
1796         struct iscsi_conn *conn = cls_conn->dd_data;
1797         struct iscsi_session *session = conn->session;
1798         uint32_t value;
1799
1800         switch(param) {
1801         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1802                 sscanf(buf, "%d", &conn->max_recv_dlength);
1803                 break;
1804         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1805                 sscanf(buf, "%d", &conn->max_xmit_dlength);
1806                 break;
1807         case ISCSI_PARAM_HDRDGST_EN:
1808                 sscanf(buf, "%d", &conn->hdrdgst_en);
1809                 break;
1810         case ISCSI_PARAM_DATADGST_EN:
1811                 sscanf(buf, "%d", &conn->datadgst_en);
1812                 break;
1813         case ISCSI_PARAM_INITIAL_R2T_EN:
1814                 sscanf(buf, "%d", &session->initial_r2t_en);
1815                 break;
1816         case ISCSI_PARAM_MAX_R2T:
1817                 sscanf(buf, "%d", &session->max_r2t);
1818                 break;
1819         case ISCSI_PARAM_IMM_DATA_EN:
1820                 sscanf(buf, "%d", &session->imm_data_en);
1821                 break;
1822         case ISCSI_PARAM_FIRST_BURST:
1823                 sscanf(buf, "%d", &session->first_burst);
1824                 break;
1825         case ISCSI_PARAM_MAX_BURST:
1826                 sscanf(buf, "%d", &session->max_burst);
1827                 break;
1828         case ISCSI_PARAM_PDU_INORDER_EN:
1829                 sscanf(buf, "%d", &session->pdu_inorder_en);
1830                 break;
1831         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1832                 sscanf(buf, "%d", &session->dataseq_inorder_en);
1833                 break;
1834         case ISCSI_PARAM_ERL:
1835                 sscanf(buf, "%d", &session->erl);
1836                 break;
1837         case ISCSI_PARAM_IFMARKER_EN:
1838                 sscanf(buf, "%d", &value);
1839                 BUG_ON(value);
1840                 break;
1841         case ISCSI_PARAM_OFMARKER_EN:
1842                 sscanf(buf, "%d", &value);
1843                 BUG_ON(value);
1844                 break;
1845         case ISCSI_PARAM_EXP_STATSN:
1846                 sscanf(buf, "%u", &conn->exp_statsn);
1847                 break;
1848         case ISCSI_PARAM_TARGET_NAME:
1849                 /* this should not change between logins */
1850                 if (session->targetname)
1851                         break;
1852
1853                 session->targetname = kstrdup(buf, GFP_KERNEL);
1854                 if (!session->targetname)
1855                         return -ENOMEM;
1856                 break;
1857         case ISCSI_PARAM_TPGT:
1858                 sscanf(buf, "%d", &session->tpgt);
1859                 break;
1860         case ISCSI_PARAM_PERSISTENT_PORT:
1861                 sscanf(buf, "%d", &conn->persistent_port);
1862                 break;
1863         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1864                 /*
1865                  * this is the address returned in discovery so it should
1866                  * not change between logins.
1867                  */
1868                 if (conn->persistent_address)
1869                         break;
1870
1871                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
1872                 if (!conn->persistent_address)
1873                         return -ENOMEM;
1874                 break;
1875         default:
1876                 return -ENOSYS;
1877         }
1878
1879         return 0;
1880 }
1881 EXPORT_SYMBOL_GPL(iscsi_set_param);
1882
1883 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
1884                             enum iscsi_param param, char *buf)
1885 {
1886         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1887         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1888         int len;
1889
1890         switch(param) {
1891         case ISCSI_PARAM_INITIAL_R2T_EN:
1892                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
1893                 break;
1894         case ISCSI_PARAM_MAX_R2T:
1895                 len = sprintf(buf, "%hu\n", session->max_r2t);
1896                 break;
1897         case ISCSI_PARAM_IMM_DATA_EN:
1898                 len = sprintf(buf, "%d\n", session->imm_data_en);
1899                 break;
1900         case ISCSI_PARAM_FIRST_BURST:
1901                 len = sprintf(buf, "%u\n", session->first_burst);
1902                 break;
1903         case ISCSI_PARAM_MAX_BURST:
1904                 len = sprintf(buf, "%u\n", session->max_burst);
1905                 break;
1906         case ISCSI_PARAM_PDU_INORDER_EN:
1907                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
1908                 break;
1909         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1910                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
1911                 break;
1912         case ISCSI_PARAM_ERL:
1913                 len = sprintf(buf, "%d\n", session->erl);
1914                 break;
1915         case ISCSI_PARAM_TARGET_NAME:
1916                 len = sprintf(buf, "%s\n", session->targetname);
1917                 break;
1918         case ISCSI_PARAM_TPGT:
1919                 len = sprintf(buf, "%d\n", session->tpgt);
1920                 break;
1921         default:
1922                 return -ENOSYS;
1923         }
1924
1925         return len;
1926 }
1927 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
1928
1929 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
1930                          enum iscsi_param param, char *buf)
1931 {
1932         struct iscsi_conn *conn = cls_conn->dd_data;
1933         int len;
1934
1935         switch(param) {
1936         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1937                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
1938                 break;
1939         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1940                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
1941                 break;
1942         case ISCSI_PARAM_HDRDGST_EN:
1943                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
1944                 break;
1945         case ISCSI_PARAM_DATADGST_EN:
1946                 len = sprintf(buf, "%d\n", conn->datadgst_en);
1947                 break;
1948         case ISCSI_PARAM_IFMARKER_EN:
1949                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
1950                 break;
1951         case ISCSI_PARAM_OFMARKER_EN:
1952                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
1953                 break;
1954         case ISCSI_PARAM_EXP_STATSN:
1955                 len = sprintf(buf, "%u\n", conn->exp_statsn);
1956                 break;
1957         case ISCSI_PARAM_PERSISTENT_PORT:
1958                 len = sprintf(buf, "%d\n", conn->persistent_port);
1959                 break;
1960         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1961                 len = sprintf(buf, "%s\n", conn->persistent_address);
1962                 break;
1963         default:
1964                 return -ENOSYS;
1965         }
1966
1967         return len;
1968 }
1969 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
1970
1971 MODULE_AUTHOR("Mike Christie");
1972 MODULE_DESCRIPTION("iSCSI library functions");
1973 MODULE_LICENSE("GPL");