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                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 485                                 rc = ISCSI_ERR_CONN_FAILED;
 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 static int iscsi_xmit_imm_task(struct iscsi_conn *conn)
 582 {
 583         struct iscsi_hdr *hdr = conn->mtask->hdr;
 584         int rc, was_logout = 0;
 585
 586         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT) {
 587                 conn->session->state = ISCSI_STATE_IN_RECOVERY;
 588                 iscsi_block_session(session_to_cls(conn->session));
 589                 was_logout = 1;
 590         }
 591         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
 592         if (rc)
 593                 return rc;
 594
 595         if (was_logout) {
 596                 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 597                 return -ENODATA;
 598         }
 599         return 0;
 600 }
 601
 602 /**
 603  * iscsi_data_xmit - xmit any command into the scheduled connection
 604  * @conn: iscsi connection
 605  *
 606  * Notes:
 607  *      The function can return -EAGAIN in which case the caller must
 608  *      re-schedule it again later or recover. '0' return code means
 609  *      successful xmit.
 610  **/
 611 static int iscsi_data_xmit(struct iscsi_conn *conn)
 612 {
 613         struct iscsi_transport *tt;
 614         int rc = 0;
 615
 616         if (unlikely(conn->suspend_tx)) {
 617                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 618                 return -ENODATA;
 619         }
 620         tt = conn->session->tt;
 621
 622         /*
 623          * Transmit in the following order:
 624          *
 625          * 1) un-finished xmit (ctask or mtask)
 626          * 2) immediate control PDUs
 627          * 3) write data
 628          * 4) SCSI commands
 629          * 5) non-immediate control PDUs
 630          *
 631          * No need to lock around __kfifo_get as long as
 632          * there's one producer and one consumer.
 633          */
 634
 635         BUG_ON(conn->ctask && conn->mtask);
 636
 637         if (conn->ctask) {
 638                 iscsi_get_ctask(conn->ctask);
 639                 rc = tt->xmit_cmd_task(conn, conn->ctask);
 640                 iscsi_put_ctask(conn->ctask);
 641                 if (rc)
 642                         goto again;
 643                 /* done with this in-progress ctask */
 644                 conn->ctask = NULL;
 645         }
 646         if (conn->mtask) {
 647                 rc = iscsi_xmit_imm_task(conn);
 648                 if (rc)
 649                         goto again;
 650                 /* done with this in-progress mtask */
 651                 conn->mtask = NULL;
 652         }
 653
 654         /* process immediate first */
 655         if (unlikely(__kfifo_len(conn->immqueue))) {
 656                 while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
 657                                    sizeof(void*))) {
 658                         spin_lock_bh(&conn->session->lock);
 659                         list_add_tail(&conn->mtask->running,
 660                                       &conn->mgmt_run_list);
 661                         spin_unlock_bh(&conn->session->lock);
 662                         rc = iscsi_xmit_imm_task(conn);
 663                         if (rc)
 664                                 goto again;
 665                 }
 666                 /* done with this mtask */
 667                 conn->mtask = NULL;
 668         }
 669
 670         /* process command queue */
 671         spin_lock_bh(&conn->session->lock);
 672         while (!list_empty(&conn->xmitqueue)) {
 673                 /*
 674                  * iscsi tcp may readd the task to the xmitqueue to send
 675                  * write data
 676                  */
 677                 conn->ctask = list_entry(conn->xmitqueue.next,
 678                                          struct iscsi_cmd_task, running);
 679                 conn->ctask->state = ISCSI_TASK_RUNNING;
 680                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
 681                 __iscsi_get_ctask(conn->ctask);
 682                 spin_unlock_bh(&conn->session->lock);
 683
 684                 rc = tt->xmit_cmd_task(conn, conn->ctask);
 685
 686                 spin_lock_bh(&conn->session->lock);
 687                 __iscsi_put_ctask(conn->ctask);
 688                 if (rc) {
 689                         spin_unlock_bh(&conn->session->lock);
 690                         goto again;
 691                 }
 692         }
 693         spin_unlock_bh(&conn->session->lock);
 694         /* done with this ctask */
 695         conn->ctask = NULL;
 696
 697         /* process the rest control plane PDUs, if any */
 698         if (unlikely(__kfifo_len(conn->mgmtqueue))) {
 699                 while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
 700                                    sizeof(void*))) {
 701                         spin_lock_bh(&conn->session->lock);
 702                         list_add_tail(&conn->mtask->running,
 703                                       &conn->mgmt_run_list);
 704                         spin_unlock_bh(&conn->session->lock);
 705                         rc = tt->xmit_mgmt_task(conn, conn->mtask);
 706                         if (rc)
 707                                 goto again;
 708                 }
 709                 /* done with this mtask */
 710                 conn->mtask = NULL;
 711         }
 712
 713         return -ENODATA;
 714
 715 again:
 716         if (unlikely(conn->suspend_tx))
 717                 return -ENODATA;
 718
 719         return rc;
 720 }
 721
 722 static void iscsi_xmitworker(void *data)
 723 {
 724         struct iscsi_conn *conn = data;
 725         int rc;
 726         /*
 727          * serialize Xmit worker on a per-connection basis.
 728          */
 729         mutex_lock(&conn->xmitmutex);
 730         do {
 731                 rc = iscsi_data_xmit(conn);
 732         } while (rc >= 0 || rc == -EAGAIN);
 733         mutex_unlock(&conn->xmitmutex);
 734 }
 735
 736 enum {
 737         FAILURE_BAD_HOST = 1,
 738         FAILURE_SESSION_FAILED,
 739         FAILURE_SESSION_FREED,
 740         FAILURE_WINDOW_CLOSED,
 741         FAILURE_OOM,
 742         FAILURE_SESSION_TERMINATE,
 743         FAILURE_SESSION_IN_RECOVERY,
 744         FAILURE_SESSION_RECOVERY_TIMEOUT,
 745 };
 746
 747 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 748 {
 749         struct Scsi_Host *host;
 750         int reason = 0;
 751         struct iscsi_session *session;
 752         struct iscsi_conn *conn;
 753         struct iscsi_cmd_task *ctask = NULL;
 754
 755         sc->scsi_done = done;
 756         sc->result = 0;
 757         sc->SCp.ptr = NULL;
 758
 759         host = sc->device->host;
 760         session = iscsi_hostdata(host->hostdata);
 761
 762         spin_lock(&session->lock);
 763
 764         /*
 765          * ISCSI_STATE_FAILED is a temp. state. The recovery
 766          * code will decide what is best to do with command queued
 767          * during this time
 768          */
 769         if (session->state != ISCSI_STATE_LOGGED_IN &&
 770             session->state != ISCSI_STATE_FAILED) {
 771                 /*
 772                  * to handle the race between when we set the recovery state
 773                  * and block the session we requeue here (commands could
 774                  * be entering our queuecommand while a block is starting
 775                  * up because the block code is not locked)
 776                  */
 777                 if (session->state == ISCSI_STATE_IN_RECOVERY) {
 778                         reason = FAILURE_SESSION_IN_RECOVERY;
 779                         goto reject;
 780                 }
 781
 782                 if (session->state == ISCSI_STATE_RECOVERY_FAILED)
 783                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
 784                 else if (session->state == ISCSI_STATE_TERMINATE)
 785                         reason = FAILURE_SESSION_TERMINATE;
 786                 else
 787                         reason = FAILURE_SESSION_FREED;
 788                 goto fault;
 789         }
 790
 791         /*
 792          * Check for iSCSI window and take care of CmdSN wrap-around
 793          */
 794         if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
 795                 reason = FAILURE_WINDOW_CLOSED;
 796                 goto reject;
 797         }
 798
 799         conn = session->leadconn;
 800         if (!conn) {
 801                 reason = FAILURE_SESSION_FREED;
 802                 goto fault;
 803         }
 804
 805         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
 806                          sizeof(void*))) {
 807                 reason = FAILURE_OOM;
 808                 goto reject;
 809         }
 810         sc->SCp.phase = session->age;
 811         sc->SCp.ptr = (char *)ctask;
 812
 813         atomic_set(&ctask->refcount, 1);
 814         ctask->state = ISCSI_TASK_PENDING;
 815         ctask->mtask = NULL;
 816         ctask->conn = conn;
 817         ctask->sc = sc;
 818         INIT_LIST_HEAD(&ctask->running);
 819         ctask->total_length = sc->request_bufflen;
 820         iscsi_prep_scsi_cmd_pdu(ctask);
 821
 822         session->tt->init_cmd_task(ctask);
 823
 824         list_add_tail(&ctask->running, &conn->xmitqueue);
 825         debug_scsi(
 826                "ctask enq [%s cid %d sc %p cdb 0x%x itt 0x%x len %d cmdsn %d "
 827                 "win %d]\n",
 828                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
 829                 conn->id, sc, sc->cmnd[0], ctask->itt, sc->request_bufflen,
 830                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 831         spin_unlock(&session->lock);
 832
 833         scsi_queue_work(host, &conn->xmitwork);
 834         return 0;
 835
 836 reject:
 837         spin_unlock(&session->lock);
 838         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
 839         return SCSI_MLQUEUE_HOST_BUSY;
 840
 841 fault:
 842         spin_unlock(&session->lock);
 843         printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
 844                sc->cmnd[0], reason);
 845         sc->result = (DID_NO_CONNECT << 16);
 846         sc->resid = sc->request_bufflen;
 847         sc->scsi_done(sc);
 848         return 0;
 849 }
 850 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
 851
 852 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
 853 {
 854         if (depth > ISCSI_MAX_CMD_PER_LUN)
 855                 depth = ISCSI_MAX_CMD_PER_LUN;
 856         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 857         return sdev->queue_depth;
 858 }
 859 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
 860
 861 static int
 862 iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 863                         char *data, uint32_t data_size)
 864 {
 865         struct iscsi_session *session = conn->session;
 866         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 867         struct iscsi_mgmt_task *mtask;
 868
 869         spin_lock_bh(&session->lock);
 870         if (session->state == ISCSI_STATE_TERMINATE) {
 871                 spin_unlock_bh(&session->lock);
 872                 return -EPERM;
 873         }
 874         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
 875             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 876                 /*
 877                  * Login and Text are sent serially, in
 878                  * request-followed-by-response sequence.
 879                  * Same mtask can be used. Same ITT must be used.
 880                  * Note that login_mtask is preallocated at conn_create().
 881                  */
 882                 mtask = conn->login_mtask;
 883         else {
 884                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 885                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 886
 887                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 888                 if (!__kfifo_get(session->mgmtpool.queue,
 889                                  (void*)&mtask, sizeof(void*))) {
 890                         spin_unlock_bh(&session->lock);
 891                         return -ENOSPC;
 892                 }
 893         }
 894
 895         /*
 896          * pre-format CmdSN for outgoing PDU.
 897          */
 898         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
 899                 hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) |
 900                            (session->age << ISCSI_AGE_SHIFT);
 901                 nop->cmdsn = cpu_to_be32(session->cmdsn);
 902                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 903                     !(hdr->opcode & ISCSI_OP_IMMEDIATE))
 904                         session->cmdsn++;
 905         } else
 906                 /* do not advance CmdSN */
 907                 nop->cmdsn = cpu_to_be32(session->cmdsn);
 908
 909         if (data_size) {
 910                 memcpy(mtask->data, data, data_size);
 911                 mtask->data_count = data_size;
 912         } else
 913                 mtask->data_count = 0;
 914
 915         INIT_LIST_HEAD(&mtask->running);
 916         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
 917         if (session->tt->init_mgmt_task)
 918                 session->tt->init_mgmt_task(conn, mtask, data, data_size);
 919         spin_unlock_bh(&session->lock);
 920
 921         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 922                    hdr->opcode, hdr->itt, data_size);
 923
 924         /*
 925          * since send_pdu() could be called at least from two contexts,
 926          * we need to serialize __kfifo_put, so we don't have to take
 927          * additional lock on fast data-path
 928          */
 929         if (hdr->opcode & ISCSI_OP_IMMEDIATE)
 930                 __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
 931         else
 932                 __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
 933
 934         scsi_queue_work(session->host, &conn->xmitwork);
 935         return 0;
 936 }
 937
 938 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 939                         char *data, uint32_t data_size)
 940 {
 941         struct iscsi_conn *conn = cls_conn->dd_data;
 942         int rc;
 943
 944         mutex_lock(&conn->xmitmutex);
 945         rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
 946         mutex_unlock(&conn->xmitmutex);
 947
 948         return rc;
 949 }
 950 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 951
 952 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
 953 {
 954         struct iscsi_session *session = class_to_transport_session(cls_session);
 955         struct iscsi_conn *conn = session->leadconn;
 956
 957         spin_lock_bh(&session->lock);
 958         if (session->state != ISCSI_STATE_LOGGED_IN) {
 959                 session->state = ISCSI_STATE_RECOVERY_FAILED;
 960                 if (conn)
 961                         wake_up(&conn->ehwait);
 962         }
 963         spin_unlock_bh(&session->lock);
 964 }
 965 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
 966
 967 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
 968 {
 969         struct Scsi_Host *host = sc->device->host;
 970         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
 971         struct iscsi_conn *conn = session->leadconn;
 972         int fail_session = 0;
 973
 974         spin_lock_bh(&session->lock);
 975         if (session->state == ISCSI_STATE_TERMINATE) {
 976 failed:
 977                 debug_scsi("failing host reset: session terminated "
 978                            "[CID %d age %d]", conn->id, session->age);
 979                 spin_unlock_bh(&session->lock);
 980                 return FAILED;
 981         }
 982
 983         if (sc->SCp.phase == session->age) {
 984                 debug_scsi("failing connection CID %d due to SCSI host reset",
 985                            conn->id);
 986                 fail_session = 1;
 987         }
 988         spin_unlock_bh(&session->lock);
 989
 990         /*
 991          * we drop the lock here but the leadconn cannot be destoyed while
 992          * we are in the scsi eh
 993          */
 994         if (fail_session)
 995                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 996
 997         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
 998         wait_event_interruptible(conn->ehwait,
 999                                  session->state == ISCSI_STATE_TERMINATE ||
1000                                  session->state == ISCSI_STATE_LOGGED_IN ||
1001                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
1002         if (signal_pending(current))
1003                 flush_signals(current);
1004
1005         spin_lock_bh(&session->lock);
1006         if (session->state == ISCSI_STATE_LOGGED_IN)
1007                 printk(KERN_INFO "iscsi: host reset succeeded\n");
1008         else
1009                 goto failed;
1010         spin_unlock_bh(&session->lock);
1011
1012         return SUCCESS;
1013 }
1014 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1015
1016 static void iscsi_tmabort_timedout(unsigned long data)
1017 {
1018         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
1019         struct iscsi_conn *conn = ctask->conn;
1020         struct iscsi_session *session = conn->session;
1021
1022         spin_lock(&session->lock);
1023         if (conn->tmabort_state == TMABORT_INITIAL) {
1024                 conn->tmabort_state = TMABORT_TIMEDOUT;
1025                 debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
1026                         ctask->sc, ctask->itt);
1027                 /* unblock eh_abort() */
1028                 wake_up(&conn->ehwait);
1029         }
1030         spin_unlock(&session->lock);
1031 }
1032
1033 /* must be called with the mutex lock */
1034 static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
1035                                  struct iscsi_cmd_task *ctask)
1036 {
1037         struct iscsi_conn *conn = ctask->conn;
1038         struct iscsi_session *session = conn->session;
1039         struct iscsi_tm *hdr = &conn->tmhdr;
1040         int rc;
1041
1042         /*
1043          * ctask timed out but session is OK requests must be serialized.
1044          */
1045         memset(hdr, 0, sizeof(struct iscsi_tm));
1046         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1047         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
1048         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1049         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1050         hdr->rtt = ctask->hdr->itt;
1051         hdr->refcmdsn = ctask->hdr->cmdsn;
1052
1053         rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
1054                                      NULL, 0);
1055         if (rc) {
1056                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1057                 debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc);
1058                 return rc;
1059         }
1060
1061         debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
1062
1063         spin_lock_bh(&session->lock);
1064         ctask->mtask = (struct iscsi_mgmt_task *)
1065                         session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) -
1066                                         ISCSI_MGMT_ITT_OFFSET];
1067
1068         if (conn->tmabort_state == TMABORT_INITIAL) {
1069                 conn->tmfcmd_pdus_cnt++;
1070                 conn->tmabort_timer.expires = 10*HZ + jiffies;
1071                 conn->tmabort_timer.function = iscsi_tmabort_timedout;
1072                 conn->tmabort_timer.data = (unsigned long)ctask;
1073                 add_timer(&conn->tmabort_timer);
1074                 debug_scsi("abort set timeout [itt 0x%x]", ctask->itt);
1075         }
1076         spin_unlock_bh(&session->lock);
1077         mutex_unlock(&conn->xmitmutex);
1078
1079         /*
1080          * block eh thread until:
1081          *
1082          * 1) abort response
1083          * 2) abort timeout
1084          * 3) session is terminated or restarted or userspace has
1085          * given up on recovery
1086          */
1087         wait_event_interruptible(conn->ehwait,
1088                                  sc->SCp.phase != session->age ||
1089                                  session->state != ISCSI_STATE_LOGGED_IN ||
1090                                  conn->tmabort_state != TMABORT_INITIAL);
1091         if (signal_pending(current))
1092                 flush_signals(current);
1093         del_timer_sync(&conn->tmabort_timer);
1094
1095         mutex_lock(&conn->xmitmutex);
1096         return 0;
1097 }
1098
1099 /*
1100  * xmit mutex and session lock must be held
1101  */
1102 static struct iscsi_mgmt_task *
1103 iscsi_remove_mgmt_task(struct kfifo *fifo, uint32_t itt)
1104 {
1105         int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);
1106         struct iscsi_mgmt_task *task;
1107
1108         debug_scsi("searching %d tasks\n", nr_tasks);
1109
1110         for (i = 0; i < nr_tasks; i++) {
1111                 __kfifo_get(fifo, (void*)&task, sizeof(void*));
1112                 debug_scsi("check task %u\n", task->itt);
1113
1114                 if (task->itt == itt) {
1115                         debug_scsi("matched task\n");
1116                         return task;
1117                 }
1118
1119                 __kfifo_put(fifo, (void*)&task, sizeof(void*));
1120         }
1121         return NULL;
1122 }
1123
1124 static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
1125 {
1126         struct iscsi_conn *conn = ctask->conn;
1127         struct iscsi_session *session = conn->session;
1128
1129         if (!ctask->mtask)
1130                 return -EINVAL;
1131
1132         if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
1133                 list_del(&ctask->mtask->running);
1134         __kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
1135                     sizeof(void*));
1136         ctask->mtask = NULL;
1137         return 0;
1138 }
1139
1140 /*
1141  * session lock and xmitmutex must be held
1142  */
1143 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1144                          int err)
1145 {
1146         struct scsi_cmnd *sc;
1147
1148         sc = ctask->sc;
1149         if (!sc)
1150                 return;
1151
1152         conn->session->tt->cleanup_cmd_task(conn, ctask);
1153         iscsi_ctask_mtask_cleanup(ctask);
1154
1155         sc->result = err;
1156         sc->resid = sc->request_bufflen;
1157         /* release ref from queuecommand */
1158         __iscsi_put_ctask(ctask);
1159 }
1160
1161 int iscsi_eh_abort(struct scsi_cmnd *sc)
1162 {
1163         struct iscsi_cmd_task *ctask;
1164         struct iscsi_conn *conn;
1165         struct iscsi_session *session;
1166         int rc;
1167
1168         /*
1169          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1170          * got the command.
1171          */
1172         if (!sc->SCp.ptr) {
1173                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1174                 return SUCCESS;
1175         }
1176
1177         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1178         conn = ctask->conn;
1179         session = conn->session;
1180
1181         conn->eh_abort_cnt++;
1182         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1183
1184         mutex_lock(&conn->xmitmutex);
1185         spin_lock_bh(&session->lock);
1186
1187         /*
1188          * If we are not logged in or we have started a new session
1189          * then let the host reset code handle this
1190          */
1191         if (session->state != ISCSI_STATE_LOGGED_IN ||
1192             sc->SCp.phase != session->age)
1193                 goto failed;
1194
1195         /* ctask completed before time out */
1196         if (!ctask->sc) {
1197                 spin_unlock_bh(&session->lock);
1198                 debug_scsi("sc completed while abort in progress\n");
1199                 goto success_rel_mutex;
1200         }
1201
1202         /* what should we do here ? */
1203         if (conn->ctask == ctask) {
1204                 printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. "
1205                        "Failing abort\n", sc, ctask->itt);
1206                 goto failed;
1207         }
1208
1209         if (ctask->state == ISCSI_TASK_PENDING)
1210                 goto success_cleanup;
1211
1212         conn->tmabort_state = TMABORT_INITIAL;
1213
1214         spin_unlock_bh(&session->lock);
1215         rc = iscsi_exec_abort_task(sc, ctask);
1216         spin_lock_bh(&session->lock);
1217
1218         if (rc || sc->SCp.phase != session->age ||
1219             session->state != ISCSI_STATE_LOGGED_IN)
1220                 goto failed;
1221         iscsi_ctask_mtask_cleanup(ctask);
1222
1223         switch (conn->tmabort_state) {
1224         case TMABORT_SUCCESS:
1225                 goto success_cleanup;
1226         case TMABORT_NOT_FOUND:
1227                 if (!ctask->sc) {
1228                         /* ctask completed before tmf abort response */
1229                         spin_unlock_bh(&session->lock);
1230                         debug_scsi("sc completed while abort in progress\n");
1231                         goto success_rel_mutex;
1232                 }
1233                 /* fall through */
1234         default:
1235                 /* timedout or failed */
1236                 spin_unlock_bh(&session->lock);
1237                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1238                 spin_lock_bh(&session->lock);
1239                 goto failed;
1240         }
1241
1242 success_cleanup:
1243         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1244         spin_unlock_bh(&session->lock);
1245
1246         /*
1247          * clean up task if aborted. we have the xmitmutex so grab
1248          * the recv lock as a writer
1249          */
1250         write_lock_bh(conn->recv_lock);
1251         spin_lock(&session->lock);
1252         fail_command(conn, ctask, DID_ABORT << 16);
1253         spin_unlock(&session->lock);
1254         write_unlock_bh(conn->recv_lock);
1255
1256 success_rel_mutex:
1257         mutex_unlock(&conn->xmitmutex);
1258         return SUCCESS;
1259
1260 failed:
1261         spin_unlock_bh(&session->lock);
1262         mutex_unlock(&conn->xmitmutex);
1263
1264         debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1265         return FAILED;
1266 }
1267 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1268
1269 int
1270 iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
1271 {
1272         int i;
1273
1274         *items = kmalloc(max * sizeof(void*), GFP_KERNEL);
1275         if (*items == NULL)
1276                 return -ENOMEM;
1277
1278         q->max = max;
1279         q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
1280         if (q->pool == NULL) {
1281                 kfree(*items);
1282                 return -ENOMEM;
1283         }
1284
1285         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1286                               GFP_KERNEL, NULL);
1287         if (q->queue == ERR_PTR(-ENOMEM)) {
1288                 kfree(q->pool);
1289                 kfree(*items);
1290                 return -ENOMEM;
1291         }
1292
1293         for (i = 0; i < max; i++) {
1294                 q->pool[i] = kmalloc(item_size, GFP_KERNEL);
1295                 if (q->pool[i] == NULL) {
1296                         int j;
1297
1298                         for (j = 0; j < i; j++)
1299                                 kfree(q->pool[j]);
1300
1301                         kfifo_free(q->queue);
1302                         kfree(q->pool);
1303                         kfree(*items);
1304                         return -ENOMEM;
1305                 }
1306                 memset(q->pool[i], 0, item_size);
1307                 (*items)[i] = q->pool[i];
1308                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1309         }
1310         return 0;
1311 }
1312 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1313
1314 void iscsi_pool_free(struct iscsi_queue *q, void **items)
1315 {
1316         int i;
1317
1318         for (i = 0; i < q->max; i++)
1319                 kfree(items[i]);
1320         kfree(q->pool);
1321         kfree(items);
1322 }
1323 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1324
1325 /*
1326  * iSCSI Session's hostdata organization:
1327  *
1328  *    *------------------* <== hostdata_session(host->hostdata)
1329  *    | ptr to class sess|
1330  *    |------------------| <== iscsi_hostdata(host->hostdata)
1331  *    | iscsi_session    |
1332  *    *------------------*
1333  */
1334
1335 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1336                                  _sz % sizeof(unsigned long))
1337
1338 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1339
1340 /**
1341  * iscsi_session_setup - create iscsi cls session and host and session
1342  * @scsit: scsi transport template
1343  * @iscsit: iscsi transport template
1344  * @initial_cmdsn: initial CmdSN
1345  * @hostno: host no allocated
1346  *
1347  * This can be used by software iscsi_transports that allocate
1348  * a session per scsi host.
1349  **/
1350 struct iscsi_cls_session *
1351 iscsi_session_setup(struct iscsi_transport *iscsit,
1352                     struct scsi_transport_template *scsit,
1353                     int cmd_task_size, int mgmt_task_size,
1354                     uint32_t initial_cmdsn, uint32_t *hostno)
1355 {
1356         struct Scsi_Host *shost;
1357         struct iscsi_session *session;
1358         struct iscsi_cls_session *cls_session;
1359         int cmd_i;
1360
1361         shost = scsi_host_alloc(iscsit->host_template,
1362                                 hostdata_privsize(sizeof(*session)));
1363         if (!shost)
1364                 return NULL;
1365
1366         shost->max_id = 1;
1367         shost->max_channel = 0;
1368         shost->max_lun = iscsit->max_lun;
1369         shost->max_cmd_len = iscsit->max_cmd_len;
1370         shost->transportt = scsit;
1371         shost->transportt->create_work_queue = 1;
1372         *hostno = shost->host_no;
1373
1374         session = iscsi_hostdata(shost->hostdata);
1375         memset(session, 0, sizeof(struct iscsi_session));
1376         session->host = shost;
1377         session->state = ISCSI_STATE_FREE;
1378         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1379         session->cmds_max = ISCSI_XMIT_CMDS_MAX;
1380         session->cmdsn = initial_cmdsn;
1381         session->exp_cmdsn = initial_cmdsn + 1;
1382         session->max_cmdsn = initial_cmdsn + 1;
1383         session->max_r2t = 1;
1384         session->tt = iscsit;
1385
1386         /* initialize SCSI PDU commands pool */
1387         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1388                             (void***)&session->cmds,
1389                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1390                 goto cmdpool_alloc_fail;
1391
1392         /* pre-format cmds pool with ITT */
1393         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1394                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1395
1396                 if (cmd_task_size)
1397                         ctask->dd_data = &ctask[1];
1398                 ctask->itt = cmd_i;
1399                 INIT_LIST_HEAD(&ctask->running);
1400         }
1401
1402         spin_lock_init(&session->lock);
1403
1404         /* initialize immediate command pool */
1405         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1406                            (void***)&session->mgmt_cmds,
1407                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1408                 goto mgmtpool_alloc_fail;
1409
1410
1411         /* pre-format immediate cmds pool with ITT */
1412         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1413                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1414
1415                 if (mgmt_task_size)
1416                         mtask->dd_data = &mtask[1];
1417                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1418                 INIT_LIST_HEAD(&mtask->running);
1419         }
1420
1421         if (scsi_add_host(shost, NULL))
1422                 goto add_host_fail;
1423
1424         if (!try_module_get(iscsit->owner))
1425                 goto cls_session_fail;
1426
1427         cls_session = iscsi_create_session(shost, iscsit, 0);
1428         if (!cls_session)
1429                 goto module_put;
1430         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1431
1432         return cls_session;
1433
1434 module_put:
1435         module_put(iscsit->owner);
1436 cls_session_fail:
1437         scsi_remove_host(shost);
1438 add_host_fail:
1439         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1440 mgmtpool_alloc_fail:
1441         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1442 cmdpool_alloc_fail:
1443         scsi_host_put(shost);
1444         return NULL;
1445 }
1446 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1447
1448 /**
1449  * iscsi_session_teardown - destroy session, host, and cls_session
1450  * shost: scsi host
1451  *
1452  * This can be used by software iscsi_transports that allocate
1453  * a session per scsi host.
1454  **/
1455 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1456 {
1457         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1458         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1459         struct module *owner = cls_session->transport->owner;
1460
1461         scsi_remove_host(shost);
1462
1463         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1464         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1465
1466         kfree(session->targetname);
1467
1468         iscsi_destroy_session(cls_session);
1469         scsi_host_put(shost);
1470         module_put(owner);
1471 }
1472 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1473
1474 /**
1475  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1476  * @cls_session: iscsi_cls_session
1477  * @conn_idx: cid
1478  **/
1479 struct iscsi_cls_conn *
1480 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1481 {
1482         struct iscsi_session *session = class_to_transport_session(cls_session);
1483         struct iscsi_conn *conn;
1484         struct iscsi_cls_conn *cls_conn;
1485         char *data;
1486
1487         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1488         if (!cls_conn)
1489                 return NULL;
1490         conn = cls_conn->dd_data;
1491         memset(conn, 0, sizeof(*conn));
1492
1493         conn->session = session;
1494         conn->cls_conn = cls_conn;
1495         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1496         conn->id = conn_idx;
1497         conn->exp_statsn = 0;
1498         conn->tmabort_state = TMABORT_INITIAL;
1499         INIT_LIST_HEAD(&conn->run_list);
1500         INIT_LIST_HEAD(&conn->mgmt_run_list);
1501         INIT_LIST_HEAD(&conn->xmitqueue);
1502
1503         /* initialize general immediate & non-immediate PDU commands queue */
1504         conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1505                                         GFP_KERNEL, NULL);
1506         if (conn->immqueue == ERR_PTR(-ENOMEM))
1507                 goto immqueue_alloc_fail;
1508
1509         conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1510                                         GFP_KERNEL, NULL);
1511         if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
1512                 goto mgmtqueue_alloc_fail;
1513
1514         INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
1515
1516         /* allocate login_mtask used for the login/text sequences */
1517         spin_lock_bh(&session->lock);
1518         if (!__kfifo_get(session->mgmtpool.queue,
1519                          (void*)&conn->login_mtask,
1520                          sizeof(void*))) {
1521                 spin_unlock_bh(&session->lock);
1522                 goto login_mtask_alloc_fail;
1523         }
1524         spin_unlock_bh(&session->lock);
1525
1526         data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
1527         if (!data)
1528                 goto login_mtask_data_alloc_fail;
1529         conn->login_mtask->data = conn->data = data;
1530
1531         init_timer(&conn->tmabort_timer);
1532         mutex_init(&conn->xmitmutex);
1533         init_waitqueue_head(&conn->ehwait);
1534
1535         return cls_conn;
1536
1537 login_mtask_data_alloc_fail:
1538         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1539                     sizeof(void*));
1540 login_mtask_alloc_fail:
1541         kfifo_free(conn->mgmtqueue);
1542 mgmtqueue_alloc_fail:
1543         kfifo_free(conn->immqueue);
1544 immqueue_alloc_fail:
1545         iscsi_destroy_conn(cls_conn);
1546         return NULL;
1547 }
1548 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1549
1550 /**
1551  * iscsi_conn_teardown - teardown iscsi connection
1552  * cls_conn: iscsi class connection
1553  *
1554  * TODO: we may need to make this into a two step process
1555  * like scsi-mls remove + put host
1556  */
1557 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1558 {
1559         struct iscsi_conn *conn = cls_conn->dd_data;
1560         struct iscsi_session *session = conn->session;
1561         unsigned long flags;
1562
1563         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1564         mutex_lock(&conn->xmitmutex);
1565
1566         spin_lock_bh(&session->lock);
1567         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1568         if (session->leadconn == conn) {
1569                 /*
1570                  * leading connection? then give up on recovery.
1571                  */
1572                 session->state = ISCSI_STATE_TERMINATE;
1573                 wake_up(&conn->ehwait);
1574         }
1575         spin_unlock_bh(&session->lock);
1576
1577         mutex_unlock(&conn->xmitmutex);
1578
1579         /*
1580          * Block until all in-progress commands for this connection
1581          * time out or fail.
1582          */
1583         for (;;) {
1584                 spin_lock_irqsave(session->host->host_lock, flags);
1585                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1586                         spin_unlock_irqrestore(session->host->host_lock, flags);
1587                         break;
1588                 }
1589                 spin_unlock_irqrestore(session->host->host_lock, flags);
1590                 msleep_interruptible(500);
1591                 printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
1592                        "host_failed %d\n", session->host->host_busy,
1593                        session->host->host_failed);
1594                 /*
1595                  * force eh_abort() to unblock
1596                  */
1597                 wake_up(&conn->ehwait);
1598         }
1599
1600         spin_lock_bh(&session->lock);
1601         kfree(conn->data);
1602         kfree(conn->persistent_address);
1603         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1604                     sizeof(void*));
1605         if (session->leadconn == conn) {
1606                 session->leadconn = NULL;
1607                 /* no connections exits.. reset sequencing */
1608                 session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
1609         }
1610         spin_unlock_bh(&session->lock);
1611
1612         kfifo_free(conn->immqueue);
1613         kfifo_free(conn->mgmtqueue);
1614
1615         iscsi_destroy_conn(cls_conn);
1616 }
1617 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1618
1619 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1620 {
1621         struct iscsi_conn *conn = cls_conn->dd_data;
1622         struct iscsi_session *session = conn->session;
1623
1624         if (!session) {
1625                 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1626                 return -EPERM;
1627         }
1628
1629         if ((session->imm_data_en || !session->initial_r2t_en) &&
1630              session->first_burst > session->max_burst) {
1631                 printk("iscsi: invalid burst lengths: "
1632                        "first_burst %d max_burst %d\n",
1633                        session->first_burst, session->max_burst);
1634                 return -EINVAL;
1635         }
1636
1637         spin_lock_bh(&session->lock);
1638         conn->c_stage = ISCSI_CONN_STARTED;
1639         session->state = ISCSI_STATE_LOGGED_IN;
1640
1641         switch(conn->stop_stage) {
1642         case STOP_CONN_RECOVER:
1643                 /*
1644                  * unblock eh_abort() if it is blocked. re-try all
1645                  * commands after successful recovery
1646                  */
1647                 conn->stop_stage = 0;
1648                 conn->tmabort_state = TMABORT_INITIAL;
1649                 session->age++;
1650                 spin_unlock_bh(&session->lock);
1651
1652                 iscsi_unblock_session(session_to_cls(session));
1653                 wake_up(&conn->ehwait);
1654                 return 0;
1655         case STOP_CONN_TERM:
1656                 conn->stop_stage = 0;
1657                 break;
1658         default:
1659                 break;
1660         }
1661         spin_unlock_bh(&session->lock);
1662
1663         return 0;
1664 }
1665 EXPORT_SYMBOL_GPL(iscsi_conn_start);
1666
1667 static void
1668 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
1669 {
1670         struct iscsi_mgmt_task *mtask, *tmp;
1671
1672         /* handle pending */
1673         while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
1674                __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
1675                 if (mtask == conn->login_mtask)
1676                         continue;
1677                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
1678                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1679                             sizeof(void*));
1680         }
1681
1682         /* handle running */
1683         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
1684                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
1685                 list_del(&mtask->running);
1686
1687                 if (mtask == conn->login_mtask)
1688                         continue;
1689                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1690                            sizeof(void*));
1691         }
1692
1693         conn->mtask = NULL;
1694 }
1695
1696 /* Fail commands. Mutex and session lock held and recv side suspended */
1697 static void fail_all_commands(struct iscsi_conn *conn)
1698 {
1699         struct iscsi_cmd_task *ctask, *tmp;
1700
1701         /* flush pending */
1702         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1703                 debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
1704                            ctask->itt);
1705                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1706         }
1707
1708         /* fail all other running */
1709         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1710                 debug_scsi("failing in progress sc %p itt 0x%x\n",
1711                            ctask->sc, ctask->itt);
1712                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1713         }
1714
1715         conn->ctask = NULL;
1716 }
1717
1718 static void iscsi_start_session_recovery(struct iscsi_session *session,
1719                                          struct iscsi_conn *conn, int flag)
1720 {
1721         int old_stop_stage;
1722
1723         spin_lock_bh(&session->lock);
1724         if (conn->stop_stage == STOP_CONN_TERM) {
1725                 spin_unlock_bh(&session->lock);
1726                 return;
1727         }
1728
1729         /*
1730          * When this is called for the in_login state, we only want to clean
1731          * up the login task and connection. We do not need to block and set
1732          * the recovery state again
1733          */
1734         if (flag == STOP_CONN_TERM)
1735                 session->state = ISCSI_STATE_TERMINATE;
1736         else if (conn->stop_stage != STOP_CONN_RECOVER)
1737                 session->state = ISCSI_STATE_IN_RECOVERY;
1738
1739         old_stop_stage = conn->stop_stage;
1740         conn->stop_stage = flag;
1741         conn->c_stage = ISCSI_CONN_STOPPED;
1742         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1743         spin_unlock_bh(&session->lock);
1744
1745         write_lock_bh(conn->recv_lock);
1746         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1747         write_unlock_bh(conn->recv_lock);
1748
1749         mutex_lock(&conn->xmitmutex);
1750         /*
1751          * for connection level recovery we should not calculate
1752          * header digest. conn->hdr_size used for optimization
1753          * in hdr_extract() and will be re-negotiated at
1754          * set_param() time.
1755          */
1756         if (flag == STOP_CONN_RECOVER) {
1757                 conn->hdrdgst_en = 0;
1758                 conn->datadgst_en = 0;
1759                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
1760                     old_stop_stage != STOP_CONN_RECOVER) {
1761                         debug_scsi("blocking session\n");
1762                         iscsi_block_session(session_to_cls(session));
1763                 }
1764         }
1765
1766         /*
1767          * flush queues.
1768          */
1769         spin_lock_bh(&session->lock);
1770         fail_all_commands(conn);
1771         flush_control_queues(session, conn);
1772         spin_unlock_bh(&session->lock);
1773
1774         mutex_unlock(&conn->xmitmutex);
1775 }
1776
1777 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1778 {
1779         struct iscsi_conn *conn = cls_conn->dd_data;
1780         struct iscsi_session *session = conn->session;
1781
1782         switch (flag) {
1783         case STOP_CONN_RECOVER:
1784         case STOP_CONN_TERM:
1785                 iscsi_start_session_recovery(session, conn, flag);
1786                 break;
1787         default:
1788                 printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
1789         }
1790 }
1791 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
1792
1793 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
1794                     struct iscsi_cls_conn *cls_conn, int is_leading)
1795 {
1796         struct iscsi_session *session = class_to_transport_session(cls_session);
1797         struct iscsi_conn *conn = cls_conn->dd_data;
1798
1799         spin_lock_bh(&session->lock);
1800         if (is_leading)
1801                 session->leadconn = conn;
1802         spin_unlock_bh(&session->lock);
1803
1804         /*
1805          * Unblock xmitworker(), Login Phase will pass through.
1806          */
1807         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1808         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1809         return 0;
1810 }
1811 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
1812
1813
1814 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
1815                     enum iscsi_param param, char *buf, int buflen)
1816 {
1817         struct iscsi_conn *conn = cls_conn->dd_data;
1818         struct iscsi_session *session = conn->session;
1819         uint32_t value;
1820
1821         switch(param) {
1822         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1823                 sscanf(buf, "%d", &conn->max_recv_dlength);
1824                 break;
1825         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1826                 sscanf(buf, "%d", &conn->max_xmit_dlength);
1827                 break;
1828         case ISCSI_PARAM_HDRDGST_EN:
1829                 sscanf(buf, "%d", &conn->hdrdgst_en);
1830                 break;
1831         case ISCSI_PARAM_DATADGST_EN:
1832                 sscanf(buf, "%d", &conn->datadgst_en);
1833                 break;
1834         case ISCSI_PARAM_INITIAL_R2T_EN:
1835                 sscanf(buf, "%d", &session->initial_r2t_en);
1836                 break;
1837         case ISCSI_PARAM_MAX_R2T:
1838                 sscanf(buf, "%d", &session->max_r2t);
1839                 break;
1840         case ISCSI_PARAM_IMM_DATA_EN:
1841                 sscanf(buf, "%d", &session->imm_data_en);
1842                 break;
1843         case ISCSI_PARAM_FIRST_BURST:
1844                 sscanf(buf, "%d", &session->first_burst);
1845                 break;
1846         case ISCSI_PARAM_MAX_BURST:
1847                 sscanf(buf, "%d", &session->max_burst);
1848                 break;
1849         case ISCSI_PARAM_PDU_INORDER_EN:
1850                 sscanf(buf, "%d", &session->pdu_inorder_en);
1851                 break;
1852         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1853                 sscanf(buf, "%d", &session->dataseq_inorder_en);
1854                 break;
1855         case ISCSI_PARAM_ERL:
1856                 sscanf(buf, "%d", &session->erl);
1857                 break;
1858         case ISCSI_PARAM_IFMARKER_EN:
1859                 sscanf(buf, "%d", &value);
1860                 BUG_ON(value);
1861                 break;
1862         case ISCSI_PARAM_OFMARKER_EN:
1863                 sscanf(buf, "%d", &value);
1864                 BUG_ON(value);
1865                 break;
1866         case ISCSI_PARAM_EXP_STATSN:
1867                 sscanf(buf, "%u", &conn->exp_statsn);
1868                 break;
1869         case ISCSI_PARAM_TARGET_NAME:
1870                 /* this should not change between logins */
1871                 if (session->targetname)
1872                         break;
1873
1874                 session->targetname = kstrdup(buf, GFP_KERNEL);
1875                 if (!session->targetname)
1876                         return -ENOMEM;
1877                 break;
1878         case ISCSI_PARAM_TPGT:
1879                 sscanf(buf, "%d", &session->tpgt);
1880                 break;
1881         case ISCSI_PARAM_PERSISTENT_PORT:
1882                 sscanf(buf, "%d", &conn->persistent_port);
1883                 break;
1884         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1885                 /*
1886                  * this is the address returned in discovery so it should
1887                  * not change between logins.
1888                  */
1889                 if (conn->persistent_address)
1890                         break;
1891
1892                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
1893                 if (!conn->persistent_address)
1894                         return -ENOMEM;
1895                 break;
1896         default:
1897                 return -ENOSYS;
1898         }
1899
1900         return 0;
1901 }
1902 EXPORT_SYMBOL_GPL(iscsi_set_param);
1903
1904 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
1905                             enum iscsi_param param, char *buf)
1906 {
1907         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1908         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1909         int len;
1910
1911         switch(param) {
1912         case ISCSI_PARAM_INITIAL_R2T_EN:
1913                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
1914                 break;
1915         case ISCSI_PARAM_MAX_R2T:
1916                 len = sprintf(buf, "%hu\n", session->max_r2t);
1917                 break;
1918         case ISCSI_PARAM_IMM_DATA_EN:
1919                 len = sprintf(buf, "%d\n", session->imm_data_en);
1920                 break;
1921         case ISCSI_PARAM_FIRST_BURST:
1922                 len = sprintf(buf, "%u\n", session->first_burst);
1923                 break;
1924         case ISCSI_PARAM_MAX_BURST:
1925                 len = sprintf(buf, "%u\n", session->max_burst);
1926                 break;
1927         case ISCSI_PARAM_PDU_INORDER_EN:
1928                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
1929                 break;
1930         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1931                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
1932                 break;
1933         case ISCSI_PARAM_ERL:
1934                 len = sprintf(buf, "%d\n", session->erl);
1935                 break;
1936         case ISCSI_PARAM_TARGET_NAME:
1937                 len = sprintf(buf, "%s\n", session->targetname);
1938                 break;
1939         case ISCSI_PARAM_TPGT:
1940                 len = sprintf(buf, "%d\n", session->tpgt);
1941                 break;
1942         default:
1943                 return -ENOSYS;
1944         }
1945
1946         return len;
1947 }
1948 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
1949
1950 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
1951                          enum iscsi_param param, char *buf)
1952 {
1953         struct iscsi_conn *conn = cls_conn->dd_data;
1954         int len;
1955
1956         switch(param) {
1957         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1958                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
1959                 break;
1960         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1961                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
1962                 break;
1963         case ISCSI_PARAM_HDRDGST_EN:
1964                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
1965                 break;
1966         case ISCSI_PARAM_DATADGST_EN:
1967                 len = sprintf(buf, "%d\n", conn->datadgst_en);
1968                 break;
1969         case ISCSI_PARAM_IFMARKER_EN:
1970                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
1971                 break;
1972         case ISCSI_PARAM_OFMARKER_EN:
1973                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
1974                 break;
1975         case ISCSI_PARAM_EXP_STATSN:
1976                 len = sprintf(buf, "%u\n", conn->exp_statsn);
1977                 break;
1978         case ISCSI_PARAM_PERSISTENT_PORT:
1979                 len = sprintf(buf, "%d\n", conn->persistent_port);
1980                 break;
1981         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1982                 len = sprintf(buf, "%s\n", conn->persistent_address);
1983                 break;
1984         default:
1985                 return -ENOSYS;
1986         }
1987
1988         return len;
1989 }
1990 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
1991
1992 MODULE_AUTHOR("Mike Christie");
1993 MODULE_DESCRIPTION("iSCSI library functions");
1994 MODULE_LICENSE("GPL");